Merge branch 'master' into docking

# Conflicts:
#	backends/imgui_impl_allegro5.cpp
#	backends/imgui_impl_allegro5.h
#	backends/imgui_impl_android.cpp
#	backends/imgui_impl_android.h
#	backends/imgui_impl_dx10.cpp
#	backends/imgui_impl_dx10.h
#	backends/imgui_impl_dx12.cpp
#	backends/imgui_impl_dx9.cpp
#	backends/imgui_impl_dx9.h
#	backends/imgui_impl_glfw.cpp
#	backends/imgui_impl_glfw.h
#	backends/imgui_impl_metal.h
#	backends/imgui_impl_metal.mm
#	backends/imgui_impl_opengl2.cpp
#	backends/imgui_impl_opengl2.h
#	backends/imgui_impl_opengl3.cpp
#	backends/imgui_impl_opengl3.h
#	backends/imgui_impl_sdl2.cpp
#	backends/imgui_impl_sdl2.h
#	backends/imgui_impl_sdl3.cpp
#	backends/imgui_impl_sdl3.h
#	backends/imgui_impl_vulkan.cpp
#	backends/imgui_impl_vulkan.h
#	backends/imgui_impl_win32.cpp
#	backends/imgui_impl_win32.h
#	imgui.cpp

.github/workflows/build.yml

@@ -8,6 +8,7 @@ on:
     # "scheduled" workflow, while maintaining ability to perform local CI builds.
     workflows:
       - scheduled
+      - manual
     branches:
       - master
       - docking
@@ -123,6 +124,11 @@ jobs:
         run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_glfw_vulkan/example_glfw_vulkan.vcxproj /p:Platform=Win32 /p:Configuration=Release'
         if: github.event_name == 'workflow_run'
 
+      - name: Build Win32 example_sdl2_sdlrenderer2
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_sdl2_sdlrenderer2/example_sdl2_sdlrenderer2.vcxproj /p:Platform=Win32 /p:Configuration=Release'
+        if: github.event_name == 'workflow_run'
+
       - name: Build Win32 example_sdl2_vulkan
         shell: cmd
         run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_sdl2_vulkan/example_sdl2_vulkan.vcxproj /p:Platform=Win32 /p:Configuration=Release'
@@ -168,6 +174,11 @@ jobs:
         shell: cmd
         run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_glfw_vulkan/example_glfw_vulkan.vcxproj /p:Platform=x64 /p:Configuration=Release'
 
+      - name: Build x64 example_sdl2_sdlrenderer2
+        shell: cmd
+        run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_sdl2_sdlrenderer2/example_sdl2_sdlrenderer2.vcxproj /p:Platform=x64 /p:Configuration=Release'
+        if: github.event_name == 'workflow_run'
+
       - name: Build x64 example_sdl2_vulkan
         shell: cmd
         run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_sdl2_vulkan/example_sdl2_vulkan.vcxproj /p:Platform=x64 /p:Configuration=Release'
@@ -207,7 +218,7 @@ jobs:
         run: '"%MSBUILD_PATH%\MSBuild.exe" examples/example_win32_directx12/example_win32_directx12.vcxproj /p:Platform=x64 /p:Configuration=Release'
 
   Linux:
-    runs-on: ubuntu-22.04
+    runs-on: ubuntu-24.04
     steps:
     - uses: actions/checkout@v4
 
@@ -313,6 +324,18 @@ jobs:
         EOF
         g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
 
+    - name: Build example_null (with C++20)
+      run: |
+        cat > example_single_file.cpp <<'EOF'
+
+        #define IMGUI_DISABLE_OBSOLETE_KEYIO
+        #define IMGUI_IMPLEMENTATION
+        #include "misc/single_file/imgui_single_file.h"
+        #include "examples/example_null/main.cpp"
+
+        EOF
+        g++ -I. -std=c++20 -Wall -Wformat -o example_single_file example_single_file.cpp
+
     - name: Build example_null (with IMGUI_DISABLE_DEMO_WINDOWS and IMGUI_DISABLE_DEBUG_TOOLS)
       run: |
         cat > example_single_file.cpp <<'EOF'
@@ -370,6 +393,18 @@ jobs:
         EOF
         g++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
 
+    - name: Build example_null (C++26, Clang)
+      run: |
+        cat > example_single_file.cpp <<'EOF'
+
+        #define IMGUI_IMPLEMENTATION
+        #define IMGUI_DISABLE_DEMO_WINDOWS
+        #include "misc/single_file/imgui_single_file.h"
+        #include "examples/example_null/main.cpp"
+
+        EOF
+        clang++ -I. -std=c++26 -Wall -Wformat -fno-exceptions -fno-threadsafe-statics -lc -lm -o example_single_file example_single_file.cpp
+
     - name: Build example_null (without c++ runtime, Clang)
       run: |
         cat > example_single_file.cpp <<'EOF'
@@ -422,6 +457,17 @@ jobs:
         EOF
         clang++ -I. -std=c++11 -Wall -Wformat -o example_single_file example_single_file.cpp
 
+    - name: Build example_null (single file build, c++20)
+      run: |
+        cat > example_single_file.cpp <<'EOF'
+
+        #define IMGUI_IMPLEMENTATION
+        #include "misc/single_file/imgui_single_file.h"
+        #include "examples/example_null/main.cpp"
+
+        EOF
+        clang++ -I. -std=c++20 -Wall -Wformat -o example_single_file example_single_file.cpp
+
     - name: Build example_null (without c++ runtime)
       run: |
         cat > example_single_file.cpp <<'EOF'
@@ -470,7 +516,7 @@ jobs:
         xcodebuild -project examples/example_apple_metal/example_apple_metal.xcodeproj -target example_apple_metal_ios CODE_SIGN_IDENTITY="" CODE_SIGNING_REQUIRED=NO CODE_SIGNING_ALLOWED=NO
 
   Emscripten:
-    runs-on: ubuntu-22.04
+    runs-on: ubuntu-24.04
     steps:
     - uses: actions/checkout@v4
 
@@ -481,6 +527,7 @@ jobs:
         emsdk-master/emsdk update
         emsdk-master/emsdk install latest
         emsdk-master/emsdk activate latest
+        sudo apt-get install build-essential
 
     - name: Build example_sdl2_opengl3 with Emscripten
       run: |
@@ -489,15 +536,28 @@ jobs:
         popd
         make -C examples/example_sdl2_opengl3 -f Makefile.emscripten
 
-    - name: Build example_glfw_wgpu
+    # This build compiles example_glfw_wgpu using Makefile.emscripten and Emscripten GLFW built-in implementation (-sUSE_GLFW=3)
+    # This ensures 2 things: the make build works, and the GLFW built-in implementation is tested
+    - name: Build example_glfw_wgpu with Emscripten/Makefile
       run: |
         pushd emsdk-master
         source ./emsdk_env.sh
         popd
         make -C examples/example_glfw_wgpu -f Makefile.emscripten
 
+    # This build compiles example_glfw_wgpu using CMakeLists.txt and Emscripten GLFW contrib port (--use-port=contrib.glfw3)
+    # This ensures 2 things: the CMake build works, and the GLFW contrib port is tested
+    - name: Build example_glfw_wgpu with Emscripten/CMake
+      run: |
+        pushd emsdk-master
+        source ./emsdk_env.sh
+        popd
+        emcc -v
+        emcmake cmake -B build -DCMAKE_BUILD_TYPE=Release examples/example_glfw_wgpu
+        cmake --build build
+
   Android:
-    runs-on: ubuntu-22.04
+    runs-on: ubuntu-24.04
     steps:
     - uses: actions/checkout@v4
 

.github/workflows/manual.yml

@@ -0,0 +1,12 @@
+#
+# This is a dummy workflow used to trigger full builds manually.
+#
+name: manual
+
+on: workflow_dispatch
+
+jobs:
+  manual:
+    runs-on: ubuntu-latest
+    steps:
+      - run: exit 0

.gitignore

@@ -3,6 +3,7 @@
 
 ## Dear ImGui artifacts
 imgui.ini
+imgui*.ini
 
 ## General build artifacts
 *.o

README.md

@@ -1,5 +0,0 @@
-This is a fork of [Dear ImGui](https://github.com/ocornut/imgui) to style based on Windows 98
-
-[Compare diff from master](https://github.com/JakeCoxon/imgui-win98/compare/master...JakeCoxon:win98)
-
-![Screenshot](screenshot.png)

backends/imgui_impl_allegro5.cpp

@@ -3,12 +3,13 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'ALLEGRO_BITMAP*' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy ALLEGRO_KEY_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
-//  [X] Platform: Clipboard support (from Allegro 5.1.12)
-//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
-// Issues:
-//  [ ] Renderer: The renderer is suboptimal as we need to convert vertices manually.
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy ALLEGRO_KEY_* values are obsolete since 1.87 and not supported since 1.91.5]
+//  [X] Platform: Clipboard support (from Allegro 5.1.12).
+//  [X] Platform: Mouse cursor shape and visibility (ImGuiBackendFlags_HasMouseCursors). Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+// Missing features or Issues:
+//  [ ] Renderer: The renderer is suboptimal as we need to unindex our buffers and convert vertices manually.
 //  [ ] Platform: Missing gamepad support.
+//  [ ] Renderer: Multi-viewport support (multiple windows).
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -20,6 +21,9 @@
 
 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
+//  2024-08-22: moved some OS/backend related function pointers from ImGuiIO to ImGuiPlatformIO:
+//               - io.GetClipboardTextFn    -> platform_io.Platform_GetClipboardTextFn
+//               - io.SetClipboardTextFn    -> platform_io.Platform_SetClipboardTextFn
 //  2022-11-30: Renderer: Restoring using al_draw_indexed_prim() when Allegro version is >= 5.2.5.
 //  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
 //  2022-09-26: Inputs: Renamed ImGuiKey_ModXXX introduced in 1.87 to ImGuiMod_XXX (old names still supported).
@@ -62,8 +66,8 @@
 #ifdef _WIN32
 #include <allegro5/allegro_windows.h>
 #endif
-#define ALLEGRO_HAS_CLIPBOARD           (ALLEGRO_VERSION_INT >= ((5 << 24) | (1 << 16) | (12 << 8))) // Clipboard only supported from Allegro 5.1.12
-#define ALLEGRO_HAS_DRAW_INDEXED_PRIM   (ALLEGRO_VERSION_INT >= ((5 << 24) | (2 << 16) | ( 5 << 8))) // DX9 implementation of al_draw_indexed_prim() got fixed in Allegro 5.2.5
+#define ALLEGRO_HAS_CLIPBOARD           ((ALLEGRO_VERSION_INT & ~ALLEGRO_UNSTABLE_BIT) >= ((5 << 24) | (1 << 16) | (12 << 8))) // Clipboard only supported from Allegro 5.1.12
+#define ALLEGRO_HAS_DRAW_INDEXED_PRIM   ((ALLEGRO_VERSION_INT & ~ALLEGRO_UNSTABLE_BIT) >= ((5 << 24) | (2 << 16) | ( 5 << 8))) // DX9 implementation of al_draw_indexed_prim() got fixed in Allegro 5.2.5
 
 // Visual Studio warnings
 #ifdef _MSC_VER
@@ -146,14 +150,14 @@ void ImGui_ImplAllegro5_RenderDrawData(ImDrawData* draw_data)
     // Render command lists
     for (int n = 0; n < draw_data->CmdListsCount; n++)
     {
-        const ImDrawList* cmd_list = draw_data->CmdLists[n];
+        const ImDrawList* draw_list = draw_data->CmdLists[n];
 
         ImVector<ImDrawVertAllegro>& vertices = bd->BufVertices;
 #if ALLEGRO_HAS_DRAW_INDEXED_PRIM
-        vertices.resize(cmd_list->VtxBuffer.Size);
-        for (int i = 0; i < cmd_list->VtxBuffer.Size; i++)
+        vertices.resize(draw_list->VtxBuffer.Size);
+        for (int i = 0; i < draw_list->VtxBuffer.Size; i++)
         {
-            const ImDrawVert* src_v = &cmd_list->VtxBuffer[i];
+            const ImDrawVert* src_v = &draw_list->VtxBuffer[i];
             ImDrawVertAllegro* dst_v = &vertices[i];
             DRAW_VERT_IMGUI_TO_ALLEGRO(dst_v, src_v);
         }
@@ -163,21 +167,21 @@ void ImGui_ImplAllegro5_RenderDrawData(ImDrawData* draw_data)
             // FIXME-OPT: Allegro doesn't support 16-bit indices.
             // You can '#define ImDrawIdx int' in imconfig.h to request Dear ImGui to output 32-bit indices.
             // Otherwise, we convert them from 16-bit to 32-bit at runtime here, which works perfectly but is a little wasteful.
-            bd->BufIndices.resize(cmd_list->IdxBuffer.Size);
-            for (int i = 0; i < cmd_list->IdxBuffer.Size; ++i)
-                bd->BufIndices[i] = (int)cmd_list->IdxBuffer.Data[i];
+            bd->BufIndices.resize(draw_list->IdxBuffer.Size);
+            for (int i = 0; i < draw_list->IdxBuffer.Size; ++i)
+                bd->BufIndices[i] = (int)draw_list->IdxBuffer.Data[i];
             indices = bd->BufIndices.Data;
         }
         else if (sizeof(ImDrawIdx) == 4)
         {
-            indices = (const int*)cmd_list->IdxBuffer.Data;
+            indices = (const int*)draw_list->IdxBuffer.Data;
         }
 #else
         // Allegro's implementation of al_draw_indexed_prim() for DX9 was broken until 5.2.5. Unindex buffers ourselves while converting vertex format.
-        vertices.resize(cmd_list->IdxBuffer.Size);
-        for (int i = 0; i < cmd_list->IdxBuffer.Size; i++)
+        vertices.resize(draw_list->IdxBuffer.Size);
+        for (int i = 0; i < draw_list->IdxBuffer.Size; i++)
         {
-            const ImDrawVert* src_v = &cmd_list->VtxBuffer[cmd_list->IdxBuffer[i]];
+            const ImDrawVert* src_v = &draw_list->VtxBuffer[draw_list->IdxBuffer[i]];
             ImDrawVertAllegro* dst_v = &vertices[i];
             DRAW_VERT_IMGUI_TO_ALLEGRO(dst_v, src_v);
         }
@@ -185,9 +189,9 @@ void ImGui_ImplAllegro5_RenderDrawData(ImDrawData* draw_data)
 
         // Render command lists
         ImVec2 clip_off = draw_data->DisplayPos;
-        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        for (int cmd_i = 0; cmd_i < draw_list->CmdBuffer.Size; cmd_i++)
         {
-            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            const ImDrawCmd* pcmd = &draw_list->CmdBuffer[cmd_i];
             if (pcmd->UserCallback)
             {
                 // User callback, registered via ImDrawList::AddCallback()
@@ -195,7 +199,7 @@ void ImGui_ImplAllegro5_RenderDrawData(ImDrawData* draw_data)
                 if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
                     ImGui_ImplAllegro5_SetupRenderState(draw_data);
                 else
-                    pcmd->UserCallback(cmd_list, pcmd);
+                    pcmd->UserCallback(draw_list, pcmd);
             }
             else
             {
@@ -291,7 +295,7 @@ void ImGui_ImplAllegro5_InvalidateDeviceObjects()
 }
 
 #if ALLEGRO_HAS_CLIPBOARD
-static const char* ImGui_ImplAllegro5_GetClipboardText(void*)
+static const char* ImGui_ImplAllegro5_GetClipboardText(ImGuiContext*)
 {
     ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
     if (bd->ClipboardTextData)
@@ -300,14 +304,16 @@ static const char* ImGui_ImplAllegro5_GetClipboardText(void*)
     return bd->ClipboardTextData;
 }
 
-static void ImGui_ImplAllegro5_SetClipboardText(void*, const char* text)
+static void ImGui_ImplAllegro5_SetClipboardText(ImGuiContext*, const char* text)
 {
     ImGui_ImplAllegro5_Data* bd = ImGui_ImplAllegro5_GetBackendData();
     al_set_clipboard_text(bd->Display, text);
 }
 #endif
 
-static ImGuiKey ImGui_ImplAllegro5_KeyCodeToImGuiKey(int key_code)
+// Not static to allow third-party code to use that if they want to (but undocumented)
+ImGuiKey ImGui_ImplAllegro5_KeyCodeToImGuiKey(int key_code);
+ImGuiKey ImGui_ImplAllegro5_KeyCodeToImGuiKey(int key_code)
 {
     switch (key_code)
     {
@@ -447,9 +453,9 @@ bool ImGui_ImplAllegro5_Init(ALLEGRO_DISPLAY* display)
     bd->VertexDecl = al_create_vertex_decl(elems, sizeof(ImDrawVertAllegro));
 
 #if ALLEGRO_HAS_CLIPBOARD
-    io.SetClipboardTextFn = ImGui_ImplAllegro5_SetClipboardText;
-    io.GetClipboardTextFn = ImGui_ImplAllegro5_GetClipboardText;
-    io.ClipboardUserData = nullptr;
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    platform_io.Platform_SetClipboardTextFn = ImGui_ImplAllegro5_SetClipboardText;
+    platform_io.Platform_GetClipboardTextFn = ImGui_ImplAllegro5_GetClipboardText;
 #endif
 
     return true;

backends/imgui_impl_allegro5.h

@@ -3,12 +3,13 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'ALLEGRO_BITMAP*' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy ALLEGRO_KEY_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
-//  [X] Platform: Clipboard support (from Allegro 5.1.12)
-//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
-// Issues:
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy ALLEGRO_KEY_* values are obsolete since 1.87 and not supported since 1.91.5]
+//  [X] Platform: Clipboard support (from Allegro 5.1.12).
+//  [X] Platform: Mouse cursor shape and visibility (ImGuiBackendFlags_HasMouseCursors). Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+// Missing features or Issues:
 //  [ ] Renderer: The renderer is suboptimal as we need to unindex our buffers and convert vertices manually.
 //  [ ] Platform: Missing gamepad support.
+//  [ ] Renderer: Multi-viewport support (multiple windows).
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -25,6 +26,7 @@
 struct ALLEGRO_DISPLAY;
 union ALLEGRO_EVENT;
 
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
 IMGUI_IMPL_API bool     ImGui_ImplAllegro5_Init(ALLEGRO_DISPLAY* display);
 IMGUI_IMPL_API void     ImGui_ImplAllegro5_Shutdown();
 IMGUI_IMPL_API void     ImGui_ImplAllegro5_NewFrame();

backends/imgui_impl_android.cpp

@@ -2,12 +2,13 @@
 // This needs to be used along with the OpenGL 3 Renderer (imgui_impl_opengl3)
 
 // Implemented features:
-//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy AKEYCODE_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy AKEYCODE_* values are obsolete since 1.87 and not supported since 1.91.5]
 //  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen/Pen.
-// Missing features:
+// Missing features or Issues:
 //  [ ] Platform: Clipboard support.
 //  [ ] Platform: Gamepad support. Enable with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
-//  [ ] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'. FIXME: Check if this is even possible with Android.
+//  [ ] Platform: Mouse cursor shape and visibility (ImGuiBackendFlags_HasMouseCursors). Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'. FIXME: Check if this is even possible with Android.
+//  [ ] Platform: Multi-viewport support (multiple windows). Not meaningful on Android.
 // Important:
 //  - Consider using SDL or GLFW backend on Android, which will be more full-featured than this.
 //  - FIXME: On-screen keyboard currently needs to be enabled by the application (see examples/ and issue #3446)

backends/imgui_impl_android.h

@@ -2,12 +2,13 @@
 // This needs to be used along with the OpenGL 3 Renderer (imgui_impl_opengl3)
 
 // Implemented features:
-//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy AKEYCODE_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy AKEYCODE_* values are obsolete since 1.87 and not supported since 1.91.5]
 //  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen/Pen.
-// Missing features:
+// Missing features or Issues:
 //  [ ] Platform: Clipboard support.
 //  [ ] Platform: Gamepad support. Enable with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
-//  [ ] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'. FIXME: Check if this is even possible with Android.
+//  [ ] Platform: Mouse cursor shape and visibility (ImGuiBackendFlags_HasMouseCursors). Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'. FIXME: Check if this is even possible with Android.
+//  [ ] Platform: Multi-viewport support (multiple windows). Not meaningful on Android.
 // Important:
 //  - Consider using SDL or GLFW backend on Android, which will be more full-featured than this.
 //  - FIXME: On-screen keyboard currently needs to be enabled by the application (see examples/ and issue #3446)
@@ -28,6 +29,7 @@
 struct ANativeWindow;
 struct AInputEvent;
 
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
 IMGUI_IMPL_API bool     ImGui_ImplAndroid_Init(ANativeWindow* window);
 IMGUI_IMPL_API int32_t  ImGui_ImplAndroid_HandleInputEvent(const AInputEvent* input_event);
 IMGUI_IMPL_API void     ImGui_ImplAndroid_Shutdown();

backends/imgui_impl_dx10.cpp

@@ -3,7 +3,8 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'ID3D10ShaderResourceView*' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
+//  [X] Renderer: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -15,6 +16,8 @@
 
 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
+//  2024-XX-XX: Platform: Added support for multiple windows via the ImGuiPlatformIO interface.
+//  2024-10-07: DirectX10: Changed default texture sampler to Clamp instead of Repeat/Wrap.
 //  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
 //  2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
 //  2021-05-19: DirectX10: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement)
@@ -79,8 +82,12 @@ static ImGui_ImplDX10_Data* ImGui_ImplDX10_GetBackendData()
     return ImGui::GetCurrentContext() ? (ImGui_ImplDX10_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
 }
 
+// Forward Declarations
+static void ImGui_ImplDX10_InitMultiViewportSupport();
+static void ImGui_ImplDX10_ShutdownMultiViewportSupport();
+
 // Functions
-static void ImGui_ImplDX10_SetupRenderState(ImDrawData* draw_data, ID3D10Device* ctx)
+static void ImGui_ImplDX10_SetupRenderState(ImDrawData* draw_data, ID3D10Device* device)
 {
     ImGui_ImplDX10_Data* bd = ImGui_ImplDX10_GetBackendData();
 
@@ -92,26 +99,26 @@ static void ImGui_ImplDX10_SetupRenderState(ImDrawData* draw_data, ID3D10Device*
     vp.MinDepth = 0.0f;
     vp.MaxDepth = 1.0f;
     vp.TopLeftX = vp.TopLeftY = 0;
-    ctx->RSSetViewports(1, &vp);
+    device->RSSetViewports(1, &vp);
 
     // Bind shader and vertex buffers
     unsigned int stride = sizeof(ImDrawVert);
     unsigned int offset = 0;
-    ctx->IASetInputLayout(bd->pInputLayout);
-    ctx->IASetVertexBuffers(0, 1, &bd->pVB, &stride, &offset);
-    ctx->IASetIndexBuffer(bd->pIB, sizeof(ImDrawIdx) == 2 ? DXGI_FORMAT_R16_UINT : DXGI_FORMAT_R32_UINT, 0);
-    ctx->IASetPrimitiveTopology(D3D10_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
-    ctx->VSSetShader(bd->pVertexShader);
-    ctx->VSSetConstantBuffers(0, 1, &bd->pVertexConstantBuffer);
-    ctx->PSSetShader(bd->pPixelShader);
-    ctx->PSSetSamplers(0, 1, &bd->pFontSampler);
-    ctx->GSSetShader(nullptr);
+    device->IASetInputLayout(bd->pInputLayout);
+    device->IASetVertexBuffers(0, 1, &bd->pVB, &stride, &offset);
+    device->IASetIndexBuffer(bd->pIB, sizeof(ImDrawIdx) == 2 ? DXGI_FORMAT_R16_UINT : DXGI_FORMAT_R32_UINT, 0);
+    device->IASetPrimitiveTopology(D3D10_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
+    device->VSSetShader(bd->pVertexShader);
+    device->VSSetConstantBuffers(0, 1, &bd->pVertexConstantBuffer);
+    device->PSSetShader(bd->pPixelShader);
+    device->PSSetSamplers(0, 1, &bd->pFontSampler);
+    device->GSSetShader(nullptr);
 
     // Setup render state
     const float blend_factor[4] = { 0.f, 0.f, 0.f, 0.f };
-    ctx->OMSetBlendState(bd->pBlendState, blend_factor, 0xffffffff);
-    ctx->OMSetDepthStencilState(bd->pDepthStencilState, 0);
-    ctx->RSSetState(bd->pRasterizerState);
+    device->OMSetBlendState(bd->pBlendState, blend_factor, 0xffffffff);
+    device->OMSetDepthStencilState(bd->pDepthStencilState, 0);
+    device->RSSetState(bd->pRasterizerState);
 }
 
 // Render function
@@ -122,7 +129,7 @@ void ImGui_ImplDX10_RenderDrawData(ImDrawData* draw_data)
         return;
 
     ImGui_ImplDX10_Data* bd = ImGui_ImplDX10_GetBackendData();
-    ID3D10Device* ctx = bd->pd3dDevice;
+    ID3D10Device* device = bd->pd3dDevice;
 
     // Create and grow vertex/index buffers if needed
     if (!bd->pVB || bd->VertexBufferSize < draw_data->TotalVtxCount)
@@ -136,7 +143,7 @@ void ImGui_ImplDX10_RenderDrawData(ImDrawData* draw_data)
         desc.BindFlags = D3D10_BIND_VERTEX_BUFFER;
         desc.CPUAccessFlags = D3D10_CPU_ACCESS_WRITE;
         desc.MiscFlags = 0;
-        if (ctx->CreateBuffer(&desc, nullptr, &bd->pVB) < 0)
+        if (device->CreateBuffer(&desc, nullptr, &bd->pVB) < 0)
             return;
     }
 
@@ -150,7 +157,7 @@ void ImGui_ImplDX10_RenderDrawData(ImDrawData* draw_data)
         desc.ByteWidth = bd->IndexBufferSize * sizeof(ImDrawIdx);
         desc.BindFlags = D3D10_BIND_INDEX_BUFFER;
         desc.CPUAccessFlags = D3D10_CPU_ACCESS_WRITE;
-        if (ctx->CreateBuffer(&desc, nullptr, &bd->pIB) < 0)
+        if (device->CreateBuffer(&desc, nullptr, &bd->pIB) < 0)
             return;
     }
 
@@ -161,11 +168,11 @@ void ImGui_ImplDX10_RenderDrawData(ImDrawData* draw_data)
     bd->pIB->Map(D3D10_MAP_WRITE_DISCARD, 0, (void**)&idx_dst);
     for (int n = 0; n < draw_data->CmdListsCount; n++)
     {
-        const ImDrawList* cmd_list = draw_data->CmdLists[n];
-        memcpy(vtx_dst, cmd_list->VtxBuffer.Data, cmd_list->VtxBuffer.Size * sizeof(ImDrawVert));
-        memcpy(idx_dst, cmd_list->IdxBuffer.Data, cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx));
-        vtx_dst += cmd_list->VtxBuffer.Size;
-        idx_dst += cmd_list->IdxBuffer.Size;
+        const ImDrawList* draw_list = draw_data->CmdLists[n];
+        memcpy(vtx_dst, draw_list->VtxBuffer.Data, draw_list->VtxBuffer.Size * sizeof(ImDrawVert));
+        memcpy(idx_dst, draw_list->IdxBuffer.Data, draw_list->IdxBuffer.Size * sizeof(ImDrawIdx));
+        vtx_dst += draw_list->VtxBuffer.Size;
+        idx_dst += draw_list->IdxBuffer.Size;
     }
     bd->pVB->Unmap();
     bd->pIB->Unmap();
@@ -217,24 +224,24 @@ void ImGui_ImplDX10_RenderDrawData(ImDrawData* draw_data)
     };
     BACKUP_DX10_STATE old = {};
     old.ScissorRectsCount = old.ViewportsCount = D3D10_VIEWPORT_AND_SCISSORRECT_OBJECT_COUNT_PER_PIPELINE;
-    ctx->RSGetScissorRects(&old.ScissorRectsCount, old.ScissorRects);
-    ctx->RSGetViewports(&old.ViewportsCount, old.Viewports);
-    ctx->RSGetState(&old.RS);
-    ctx->OMGetBlendState(&old.BlendState, old.BlendFactor, &old.SampleMask);
-    ctx->OMGetDepthStencilState(&old.DepthStencilState, &old.StencilRef);
-    ctx->PSGetShaderResources(0, 1, &old.PSShaderResource);
-    ctx->PSGetSamplers(0, 1, &old.PSSampler);
-    ctx->PSGetShader(&old.PS);
-    ctx->VSGetShader(&old.VS);
-    ctx->VSGetConstantBuffers(0, 1, &old.VSConstantBuffer);
-    ctx->GSGetShader(&old.GS);
-    ctx->IAGetPrimitiveTopology(&old.PrimitiveTopology);
-    ctx->IAGetIndexBuffer(&old.IndexBuffer, &old.IndexBufferFormat, &old.IndexBufferOffset);
-    ctx->IAGetVertexBuffers(0, 1, &old.VertexBuffer, &old.VertexBufferStride, &old.VertexBufferOffset);
-    ctx->IAGetInputLayout(&old.InputLayout);
+    device->RSGetScissorRects(&old.ScissorRectsCount, old.ScissorRects);
+    device->RSGetViewports(&old.ViewportsCount, old.Viewports);
+    device->RSGetState(&old.RS);
+    device->OMGetBlendState(&old.BlendState, old.BlendFactor, &old.SampleMask);
+    device->OMGetDepthStencilState(&old.DepthStencilState, &old.StencilRef);
+    device->PSGetShaderResources(0, 1, &old.PSShaderResource);
+    device->PSGetSamplers(0, 1, &old.PSSampler);
+    device->PSGetShader(&old.PS);
+    device->VSGetShader(&old.VS);
+    device->VSGetConstantBuffers(0, 1, &old.VSConstantBuffer);
+    device->GSGetShader(&old.GS);
+    device->IAGetPrimitiveTopology(&old.PrimitiveTopology);
+    device->IAGetIndexBuffer(&old.IndexBuffer, &old.IndexBufferFormat, &old.IndexBufferOffset);
+    device->IAGetVertexBuffers(0, 1, &old.VertexBuffer, &old.VertexBufferStride, &old.VertexBufferOffset);
+    device->IAGetInputLayout(&old.InputLayout);
 
     // Setup desired DX state
-    ImGui_ImplDX10_SetupRenderState(draw_data, ctx);
+    ImGui_ImplDX10_SetupRenderState(draw_data, device);
 
     // Render command lists
     // (Because we merged all buffers into a single one, we maintain our own offset into them)
@@ -243,18 +250,18 @@ void ImGui_ImplDX10_RenderDrawData(ImDrawData* draw_data)
     ImVec2 clip_off = draw_data->DisplayPos;
     for (int n = 0; n < draw_data->CmdListsCount; n++)
     {
-        const ImDrawList* cmd_list = draw_data->CmdLists[n];
-        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        const ImDrawList* draw_list = draw_data->CmdLists[n];
+        for (int cmd_i = 0; cmd_i < draw_list->CmdBuffer.Size; cmd_i++)
         {
-            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            const ImDrawCmd* pcmd = &draw_list->CmdBuffer[cmd_i];
             if (pcmd->UserCallback)
             {
                 // User callback, registered via ImDrawList::AddCallback()
                 // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.)
                 if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
-                    ImGui_ImplDX10_SetupRenderState(draw_data, ctx);
+                    ImGui_ImplDX10_SetupRenderState(draw_data, device);
                 else
-                    pcmd->UserCallback(cmd_list, pcmd);
+                    pcmd->UserCallback(draw_list, pcmd);
             }
             else
             {
@@ -266,34 +273,34 @@ void ImGui_ImplDX10_RenderDrawData(ImDrawData* draw_data)
 
                 // Apply scissor/clipping rectangle
                 const D3D10_RECT r = { (LONG)clip_min.x, (LONG)clip_min.y, (LONG)clip_max.x, (LONG)clip_max.y };
-                ctx->RSSetScissorRects(1, &r);
+                device->RSSetScissorRects(1, &r);
 
                 // Bind texture, Draw
                 ID3D10ShaderResourceView* texture_srv = (ID3D10ShaderResourceView*)pcmd->GetTexID();
-                ctx->PSSetShaderResources(0, 1, &texture_srv);
-                ctx->DrawIndexed(pcmd->ElemCount, pcmd->IdxOffset + global_idx_offset, pcmd->VtxOffset + global_vtx_offset);
+                device->PSSetShaderResources(0, 1, &texture_srv);
+                device->DrawIndexed(pcmd->ElemCount, pcmd->IdxOffset + global_idx_offset, pcmd->VtxOffset + global_vtx_offset);
             }
         }
-        global_idx_offset += cmd_list->IdxBuffer.Size;
-        global_vtx_offset += cmd_list->VtxBuffer.Size;
+        global_idx_offset += draw_list->IdxBuffer.Size;
+        global_vtx_offset += draw_list->VtxBuffer.Size;
     }
 
     // Restore modified DX state
-    ctx->RSSetScissorRects(old.ScissorRectsCount, old.ScissorRects);
-    ctx->RSSetViewports(old.ViewportsCount, old.Viewports);
-    ctx->RSSetState(old.RS); if (old.RS) old.RS->Release();
-    ctx->OMSetBlendState(old.BlendState, old.BlendFactor, old.SampleMask); if (old.BlendState) old.BlendState->Release();
-    ctx->OMSetDepthStencilState(old.DepthStencilState, old.StencilRef); if (old.DepthStencilState) old.DepthStencilState->Release();
-    ctx->PSSetShaderResources(0, 1, &old.PSShaderResource); if (old.PSShaderResource) old.PSShaderResource->Release();
-    ctx->PSSetSamplers(0, 1, &old.PSSampler); if (old.PSSampler) old.PSSampler->Release();
-    ctx->PSSetShader(old.PS); if (old.PS) old.PS->Release();
-    ctx->VSSetShader(old.VS); if (old.VS) old.VS->Release();
-    ctx->GSSetShader(old.GS); if (old.GS) old.GS->Release();
-    ctx->VSSetConstantBuffers(0, 1, &old.VSConstantBuffer); if (old.VSConstantBuffer) old.VSConstantBuffer->Release();
-    ctx->IASetPrimitiveTopology(old.PrimitiveTopology);
-    ctx->IASetIndexBuffer(old.IndexBuffer, old.IndexBufferFormat, old.IndexBufferOffset); if (old.IndexBuffer) old.IndexBuffer->Release();
-    ctx->IASetVertexBuffers(0, 1, &old.VertexBuffer, &old.VertexBufferStride, &old.VertexBufferOffset); if (old.VertexBuffer) old.VertexBuffer->Release();
-    ctx->IASetInputLayout(old.InputLayout); if (old.InputLayout) old.InputLayout->Release();
+    device->RSSetScissorRects(old.ScissorRectsCount, old.ScissorRects);
+    device->RSSetViewports(old.ViewportsCount, old.Viewports);
+    device->RSSetState(old.RS); if (old.RS) old.RS->Release();
+    device->OMSetBlendState(old.BlendState, old.BlendFactor, old.SampleMask); if (old.BlendState) old.BlendState->Release();
+    device->OMSetDepthStencilState(old.DepthStencilState, old.StencilRef); if (old.DepthStencilState) old.DepthStencilState->Release();
+    device->PSSetShaderResources(0, 1, &old.PSShaderResource); if (old.PSShaderResource) old.PSShaderResource->Release();
+    device->PSSetSamplers(0, 1, &old.PSSampler); if (old.PSSampler) old.PSSampler->Release();
+    device->PSSetShader(old.PS); if (old.PS) old.PS->Release();
+    device->VSSetShader(old.VS); if (old.VS) old.VS->Release();
+    device->GSSetShader(old.GS); if (old.GS) old.GS->Release();
+    device->VSSetConstantBuffers(0, 1, &old.VSConstantBuffer); if (old.VSConstantBuffer) old.VSConstantBuffer->Release();
+    device->IASetPrimitiveTopology(old.PrimitiveTopology);
+    device->IASetIndexBuffer(old.IndexBuffer, old.IndexBufferFormat, old.IndexBufferOffset); if (old.IndexBuffer) old.IndexBuffer->Release();
+    device->IASetVertexBuffers(0, 1, &old.VertexBuffer, &old.VertexBufferStride, &old.VertexBufferOffset); if (old.VertexBuffer) old.VertexBuffer->Release();
+    device->IASetInputLayout(old.InputLayout); if (old.InputLayout) old.InputLayout->Release();
 }
 
 static void ImGui_ImplDX10_CreateFontsTexture()
@@ -340,21 +347,16 @@ static void ImGui_ImplDX10_CreateFontsTexture()
 
     // Store our identifier
     io.Fonts->SetTexID((ImTextureID)bd->pFontTextureView);
+}
 
-    // Create texture sampler
-    // (Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling)
+static void ImGui_ImplDX10_DestroyFontsTexture()
+{
+    ImGui_ImplDX10_Data* bd = ImGui_ImplDX10_GetBackendData();
+    if (bd->pFontTextureView)
     {
-        D3D10_SAMPLER_DESC desc;
-        ZeroMemory(&desc, sizeof(desc));
-        desc.Filter = D3D10_FILTER_MIN_MAG_MIP_LINEAR;
-        desc.AddressU = D3D10_TEXTURE_ADDRESS_WRAP;
-        desc.AddressV = D3D10_TEXTURE_ADDRESS_WRAP;
-        desc.AddressW = D3D10_TEXTURE_ADDRESS_WRAP;
-        desc.MipLODBias = 0.f;
-        desc.ComparisonFunc = D3D10_COMPARISON_ALWAYS;
-        desc.MinLOD = 0.f;
-        desc.MaxLOD = 0.f;
-        bd->pd3dDevice->CreateSamplerState(&desc, &bd->pFontSampler);
+        bd->pFontTextureView->Release();
+        bd->pFontTextureView = nullptr;
+        ImGui::GetIO().Fonts->SetTexID(0); // We copied bd->pFontTextureView to io.Fonts->TexID so let's clear that as well.
     }
 }
 
@@ -507,6 +509,22 @@ bool    ImGui_ImplDX10_CreateDeviceObjects()
         bd->pd3dDevice->CreateDepthStencilState(&desc, &bd->pDepthStencilState);
     }
 
+    // Create texture sampler
+    // (Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling)
+    {
+        D3D10_SAMPLER_DESC desc;
+        ZeroMemory(&desc, sizeof(desc));
+        desc.Filter = D3D10_FILTER_MIN_MAG_MIP_LINEAR;
+        desc.AddressU = D3D10_TEXTURE_ADDRESS_CLAMP;
+        desc.AddressV = D3D10_TEXTURE_ADDRESS_CLAMP;
+        desc.AddressW = D3D10_TEXTURE_ADDRESS_CLAMP;
+        desc.MipLODBias = 0.f;
+        desc.ComparisonFunc = D3D10_COMPARISON_ALWAYS;
+        desc.MinLOD = 0.f;
+        desc.MaxLOD = 0.f;
+        bd->pd3dDevice->CreateSamplerState(&desc, &bd->pFontSampler);
+    }
+
     ImGui_ImplDX10_CreateFontsTexture();
 
     return true;
@@ -518,8 +536,9 @@ void    ImGui_ImplDX10_InvalidateDeviceObjects()
     if (!bd->pd3dDevice)
         return;
 
+    ImGui_ImplDX10_DestroyFontsTexture();
+
     if (bd->pFontSampler)           { bd->pFontSampler->Release(); bd->pFontSampler = nullptr; }
-    if (bd->pFontTextureView)       { bd->pFontTextureView->Release(); bd->pFontTextureView = nullptr; ImGui::GetIO().Fonts->SetTexID(0); } // We copied bd->pFontTextureView to io.Fonts->TexID so let's clear that as well.
     if (bd->pIB)                    { bd->pIB->Release(); bd->pIB = nullptr; }
     if (bd->pVB)                    { bd->pVB->Release(); bd->pVB = nullptr; }
     if (bd->pBlendState)            { bd->pBlendState->Release(); bd->pBlendState = nullptr; }
@@ -542,6 +561,7 @@ bool    ImGui_ImplDX10_Init(ID3D10Device* device)
     io.BackendRendererUserData = (void*)bd;
     io.BackendRendererName = "imgui_impl_dx10";
     io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset;  // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
+    io.BackendFlags |= ImGuiBackendFlags_RendererHasViewports;  // We can create multi-viewports on the Renderer side (optional)
 
     // Get factory from device
     IDXGIDevice* pDXGIDevice = nullptr;
@@ -558,6 +578,8 @@ bool    ImGui_ImplDX10_Init(ID3D10Device* device)
     if (pDXGIAdapter) pDXGIAdapter->Release();
     bd->pd3dDevice->AddRef();
 
+    ImGui_ImplDX10_InitMultiViewportSupport();
+
     return true;
 }
 
@@ -567,12 +589,13 @@ void ImGui_ImplDX10_Shutdown()
     IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
     ImGuiIO& io = ImGui::GetIO();
 
+    ImGui_ImplDX10_ShutdownMultiViewportSupport();
     ImGui_ImplDX10_InvalidateDeviceObjects();
     if (bd->pFactory) { bd->pFactory->Release(); }
     if (bd->pd3dDevice) { bd->pd3dDevice->Release(); }
     io.BackendRendererName = nullptr;
     io.BackendRendererUserData = nullptr;
-    io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset;
+    io.BackendFlags &= ~(ImGuiBackendFlags_RendererHasVtxOffset | ImGuiBackendFlags_RendererHasViewports);
     IM_DELETE(bd);
 }
 
@@ -581,10 +604,133 @@ void ImGui_ImplDX10_NewFrame()
     ImGui_ImplDX10_Data* bd = ImGui_ImplDX10_GetBackendData();
     IM_ASSERT(bd != nullptr && "Context or backend not initialized! Did you call ImGui_ImplDX10_Init()?");
 
-    if (!bd->pFontSampler)
+    if (!bd->pVertexShader)
         ImGui_ImplDX10_CreateDeviceObjects();
 }
 
+//--------------------------------------------------------------------------------------------------------
+// MULTI-VIEWPORT / PLATFORM INTERFACE SUPPORT
+// This is an _advanced_ and _optional_ feature, allowing the backend to create and handle multiple viewports simultaneously.
+// If you are new to dear imgui or creating a new binding for dear imgui, it is recommended that you completely ignore this section first..
+//--------------------------------------------------------------------------------------------------------
+
+// Helper structure we store in the void* RendererUserData field of each ImGuiViewport to easily retrieve our backend data.
+struct ImGui_ImplDX10_ViewportData
+{
+    IDXGISwapChain*         SwapChain;
+    ID3D10RenderTargetView* RTView;
+
+    ImGui_ImplDX10_ViewportData()   { SwapChain = nullptr; RTView = nullptr; }
+    ~ImGui_ImplDX10_ViewportData()  { IM_ASSERT(SwapChain == nullptr && RTView == nullptr); }
+};
+
+static void ImGui_ImplDX10_CreateWindow(ImGuiViewport* viewport)
+{
+    ImGui_ImplDX10_Data* bd = ImGui_ImplDX10_GetBackendData();
+    ImGui_ImplDX10_ViewportData* vd = IM_NEW(ImGui_ImplDX10_ViewportData)();
+    viewport->RendererUserData = vd;
+
+    // PlatformHandleRaw should always be a HWND, whereas PlatformHandle might be a higher-level handle (e.g. GLFWWindow*, SDL_Window*).
+    // Some backends will leave PlatformHandleRaw == 0, in which case we assume PlatformHandle will contain the HWND.
+    HWND hwnd = viewport->PlatformHandleRaw ? (HWND)viewport->PlatformHandleRaw : (HWND)viewport->PlatformHandle;
+    IM_ASSERT(hwnd != 0);
+
+    // Create swap chain
+    DXGI_SWAP_CHAIN_DESC sd;
+    ZeroMemory(&sd, sizeof(sd));
+    sd.BufferDesc.Width = (UINT)viewport->Size.x;
+    sd.BufferDesc.Height = (UINT)viewport->Size.y;
+    sd.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
+    sd.SampleDesc.Count = 1;
+    sd.SampleDesc.Quality = 0;
+    sd.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
+    sd.BufferCount = 1;
+    sd.OutputWindow = hwnd;
+    sd.Windowed = TRUE;
+    sd.SwapEffect = DXGI_SWAP_EFFECT_DISCARD;
+    sd.Flags = 0;
+
+    IM_ASSERT(vd->SwapChain == nullptr && vd->RTView == nullptr);
+    bd->pFactory->CreateSwapChain(bd->pd3dDevice, &sd, &vd->SwapChain);
+
+    // Create the render target
+    if (vd->SwapChain)
+    {
+        ID3D10Texture2D* pBackBuffer;
+        vd->SwapChain->GetBuffer(0, IID_PPV_ARGS(&pBackBuffer));
+        bd->pd3dDevice->CreateRenderTargetView(pBackBuffer, nullptr, &vd->RTView);
+        pBackBuffer->Release();
+    }
+}
+
+static void ImGui_ImplDX10_DestroyWindow(ImGuiViewport* viewport)
+{
+    // The main viewport (owned by the application) will always have RendererUserData == 0 here since we didn't create the data for it.
+    if (ImGui_ImplDX10_ViewportData* vd = (ImGui_ImplDX10_ViewportData*)viewport->RendererUserData)
+    {
+        if (vd->SwapChain)
+            vd->SwapChain->Release();
+        vd->SwapChain = nullptr;
+        if (vd->RTView)
+            vd->RTView->Release();
+        vd->RTView = nullptr;
+        IM_DELETE(vd);
+    }
+    viewport->RendererUserData = nullptr;
+}
+
+static void ImGui_ImplDX10_SetWindowSize(ImGuiViewport* viewport, ImVec2 size)
+{
+    ImGui_ImplDX10_Data* bd = ImGui_ImplDX10_GetBackendData();
+    ImGui_ImplDX10_ViewportData* vd = (ImGui_ImplDX10_ViewportData*)viewport->RendererUserData;
+    if (vd->RTView)
+    {
+        vd->RTView->Release();
+        vd->RTView = nullptr;
+    }
+    if (vd->SwapChain)
+    {
+        ID3D10Texture2D* pBackBuffer = nullptr;
+        vd->SwapChain->ResizeBuffers(0, (UINT)size.x, (UINT)size.y, DXGI_FORMAT_UNKNOWN, 0);
+        vd->SwapChain->GetBuffer(0, IID_PPV_ARGS(&pBackBuffer));
+        if (pBackBuffer == nullptr) { fprintf(stderr, "ImGui_ImplDX10_SetWindowSize() failed creating buffers.\n"); return; }
+        bd->pd3dDevice->CreateRenderTargetView(pBackBuffer, nullptr, &vd->RTView);
+        pBackBuffer->Release();
+    }
+}
+
+static void ImGui_ImplDX10_RenderViewport(ImGuiViewport* viewport, void*)
+{
+    ImGui_ImplDX10_Data* bd = ImGui_ImplDX10_GetBackendData();
+    ImGui_ImplDX10_ViewportData* vd = (ImGui_ImplDX10_ViewportData*)viewport->RendererUserData;
+    ImVec4 clear_color = ImVec4(0.0f, 0.0f, 0.0f, 1.0f);
+    bd->pd3dDevice->OMSetRenderTargets(1, &vd->RTView, nullptr);
+    if (!(viewport->Flags & ImGuiViewportFlags_NoRendererClear))
+        bd->pd3dDevice->ClearRenderTargetView(vd->RTView, (float*)&clear_color);
+    ImGui_ImplDX10_RenderDrawData(viewport->DrawData);
+}
+
+static void ImGui_ImplDX10_SwapBuffers(ImGuiViewport* viewport, void*)
+{
+    ImGui_ImplDX10_ViewportData* vd = (ImGui_ImplDX10_ViewportData*)viewport->RendererUserData;
+    vd->SwapChain->Present(0, 0); // Present without vsync
+}
+
+void ImGui_ImplDX10_InitMultiViewportSupport()
+{
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    platform_io.Renderer_CreateWindow = ImGui_ImplDX10_CreateWindow;
+    platform_io.Renderer_DestroyWindow = ImGui_ImplDX10_DestroyWindow;
+    platform_io.Renderer_SetWindowSize = ImGui_ImplDX10_SetWindowSize;
+    platform_io.Renderer_RenderWindow = ImGui_ImplDX10_RenderViewport;
+    platform_io.Renderer_SwapBuffers = ImGui_ImplDX10_SwapBuffers;
+}
+
+void ImGui_ImplDX10_ShutdownMultiViewportSupport()
+{
+    ImGui::DestroyPlatformWindows();
+}
+
 //-----------------------------------------------------------------------------
 
 #endif // #ifndef IMGUI_DISABLE

backends/imgui_impl_dx10.h

@@ -3,7 +3,8 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'ID3D10ShaderResourceView*' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
+//  [X] Renderer: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -19,13 +20,14 @@
 
 struct ID3D10Device;
 
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
 IMGUI_IMPL_API bool     ImGui_ImplDX10_Init(ID3D10Device* device);
 IMGUI_IMPL_API void     ImGui_ImplDX10_Shutdown();
 IMGUI_IMPL_API void     ImGui_ImplDX10_NewFrame();
 IMGUI_IMPL_API void     ImGui_ImplDX10_RenderDrawData(ImDrawData* draw_data);
 
 // Use if you want to reset your rendering device without losing Dear ImGui state.
-IMGUI_IMPL_API void     ImGui_ImplDX10_InvalidateDeviceObjects();
 IMGUI_IMPL_API bool     ImGui_ImplDX10_CreateDeviceObjects();
+IMGUI_IMPL_API void     ImGui_ImplDX10_InvalidateDeviceObjects();
 
 #endif // #ifndef IMGUI_DISABLE

backends/imgui_impl_dx11.cpp

@@ -3,7 +3,9 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'ID3D11ShaderResourceView*' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
+//  [X] Renderer: Expose selected render state for draw callbacks to use. Access in '(ImGui_ImplXXXX_RenderState*)GetPlatformIO().Renderer_RenderState'.
+//  [X] Renderer: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -15,12 +17,15 @@
 
 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
+//  2024-XX-XX: Platform: Added support for multiple windows via the ImGuiPlatformIO interface.
+//  2024-10-07: DirectX11: Changed default texture sampler to Clamp instead of Repeat/Wrap.
+//  2024-10-07: DirectX11: Expose selected render state in ImGui_ImplDX11_RenderState, which you can access in 'void* platform_io.Renderer_RenderState' during draw callbacks.
 //  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
 //  2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
 //  2021-05-19: DirectX11: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement)
 //  2021-02-18: DirectX11: Change blending equation to preserve alpha in output buffer.
 //  2019-08-01: DirectX11: Fixed code querying the Geometry Shader state (would generally error with Debug layer enabled).
-//  2019-07-21: DirectX11: Backup, clear and restore Geometry Shader is any is bound when calling ImGui_ImplDX10_RenderDrawData. Clearing Hull/Domain/Compute shaders without backup/restore.
+//  2019-07-21: DirectX11: Backup, clear and restore Geometry Shader is any is bound when calling ImGui_ImplDX11_RenderDrawData. Clearing Hull/Domain/Compute shaders without backup/restore.
 //  2019-05-29: DirectX11: Added support for large mesh (64K+ vertices), enable ImGuiBackendFlags_RendererHasVtxOffset flag.
 //  2019-04-30: DirectX11: Added support for special ImDrawCallback_ResetRenderState callback to reset render state.
 //  2018-12-03: Misc: Added #pragma comment statement to automatically link with d3dcompiler.lib when using D3DCompile().
@@ -80,8 +85,12 @@ static ImGui_ImplDX11_Data* ImGui_ImplDX11_GetBackendData()
     return ImGui::GetCurrentContext() ? (ImGui_ImplDX11_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
 }
 
+// Forward Declarations
+static void ImGui_ImplDX11_InitMultiViewportSupport();
+static void ImGui_ImplDX11_ShutdownMultiViewportSupport();
+
 // Functions
-static void ImGui_ImplDX11_SetupRenderState(ImDrawData* draw_data, ID3D11DeviceContext* ctx)
+static void ImGui_ImplDX11_SetupRenderState(ImDrawData* draw_data, ID3D11DeviceContext* device_ctx)
 {
     ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
 
@@ -93,29 +102,29 @@ static void ImGui_ImplDX11_SetupRenderState(ImDrawData* draw_data, ID3D11DeviceC
     vp.MinDepth = 0.0f;
     vp.MaxDepth = 1.0f;
     vp.TopLeftX = vp.TopLeftY = 0;
-    ctx->RSSetViewports(1, &vp);
+    device_ctx->RSSetViewports(1, &vp);
 
     // Setup shader and vertex buffers
     unsigned int stride = sizeof(ImDrawVert);
     unsigned int offset = 0;
-    ctx->IASetInputLayout(bd->pInputLayout);
-    ctx->IASetVertexBuffers(0, 1, &bd->pVB, &stride, &offset);
-    ctx->IASetIndexBuffer(bd->pIB, sizeof(ImDrawIdx) == 2 ? DXGI_FORMAT_R16_UINT : DXGI_FORMAT_R32_UINT, 0);
-    ctx->IASetPrimitiveTopology(D3D11_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
-    ctx->VSSetShader(bd->pVertexShader, nullptr, 0);
-    ctx->VSSetConstantBuffers(0, 1, &bd->pVertexConstantBuffer);
-    ctx->PSSetShader(bd->pPixelShader, nullptr, 0);
-    ctx->PSSetSamplers(0, 1, &bd->pFontSampler);
-    ctx->GSSetShader(nullptr, nullptr, 0);
-    ctx->HSSetShader(nullptr, nullptr, 0); // In theory we should backup and restore this as well.. very infrequently used..
-    ctx->DSSetShader(nullptr, nullptr, 0); // In theory we should backup and restore this as well.. very infrequently used..
-    ctx->CSSetShader(nullptr, nullptr, 0); // In theory we should backup and restore this as well.. very infrequently used..
+    device_ctx->IASetInputLayout(bd->pInputLayout);
+    device_ctx->IASetVertexBuffers(0, 1, &bd->pVB, &stride, &offset);
+    device_ctx->IASetIndexBuffer(bd->pIB, sizeof(ImDrawIdx) == 2 ? DXGI_FORMAT_R16_UINT : DXGI_FORMAT_R32_UINT, 0);
+    device_ctx->IASetPrimitiveTopology(D3D11_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
+    device_ctx->VSSetShader(bd->pVertexShader, nullptr, 0);
+    device_ctx->VSSetConstantBuffers(0, 1, &bd->pVertexConstantBuffer);
+    device_ctx->PSSetShader(bd->pPixelShader, nullptr, 0);
+    device_ctx->PSSetSamplers(0, 1, &bd->pFontSampler);
+    device_ctx->GSSetShader(nullptr, nullptr, 0);
+    device_ctx->HSSetShader(nullptr, nullptr, 0); // In theory we should backup and restore this as well.. very infrequently used..
+    device_ctx->DSSetShader(nullptr, nullptr, 0); // In theory we should backup and restore this as well.. very infrequently used..
+    device_ctx->CSSetShader(nullptr, nullptr, 0); // In theory we should backup and restore this as well.. very infrequently used..
 
     // Setup blend state
     const float blend_factor[4] = { 0.f, 0.f, 0.f, 0.f };
-    ctx->OMSetBlendState(bd->pBlendState, blend_factor, 0xffffffff);
-    ctx->OMSetDepthStencilState(bd->pDepthStencilState, 0);
-    ctx->RSSetState(bd->pRasterizerState);
+    device_ctx->OMSetBlendState(bd->pBlendState, blend_factor, 0xffffffff);
+    device_ctx->OMSetDepthStencilState(bd->pDepthStencilState, 0);
+    device_ctx->RSSetState(bd->pRasterizerState);
 }
 
 // Render function
@@ -126,7 +135,7 @@ void ImGui_ImplDX11_RenderDrawData(ImDrawData* draw_data)
         return;
 
     ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
-    ID3D11DeviceContext* ctx = bd->pd3dDeviceContext;
+    ID3D11DeviceContext* device = bd->pd3dDeviceContext;
 
     // Create and grow vertex/index buffers if needed
     if (!bd->pVB || bd->VertexBufferSize < draw_data->TotalVtxCount)
@@ -159,28 +168,28 @@ void ImGui_ImplDX11_RenderDrawData(ImDrawData* draw_data)
 
     // Upload vertex/index data into a single contiguous GPU buffer
     D3D11_MAPPED_SUBRESOURCE vtx_resource, idx_resource;
-    if (ctx->Map(bd->pVB, 0, D3D11_MAP_WRITE_DISCARD, 0, &vtx_resource) != S_OK)
+    if (device->Map(bd->pVB, 0, D3D11_MAP_WRITE_DISCARD, 0, &vtx_resource) != S_OK)
         return;
-    if (ctx->Map(bd->pIB, 0, D3D11_MAP_WRITE_DISCARD, 0, &idx_resource) != S_OK)
+    if (device->Map(bd->pIB, 0, D3D11_MAP_WRITE_DISCARD, 0, &idx_resource) != S_OK)
         return;
     ImDrawVert* vtx_dst = (ImDrawVert*)vtx_resource.pData;
     ImDrawIdx* idx_dst = (ImDrawIdx*)idx_resource.pData;
     for (int n = 0; n < draw_data->CmdListsCount; n++)
     {
-        const ImDrawList* cmd_list = draw_data->CmdLists[n];
-        memcpy(vtx_dst, cmd_list->VtxBuffer.Data, cmd_list->VtxBuffer.Size * sizeof(ImDrawVert));
-        memcpy(idx_dst, cmd_list->IdxBuffer.Data, cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx));
-        vtx_dst += cmd_list->VtxBuffer.Size;
-        idx_dst += cmd_list->IdxBuffer.Size;
+        const ImDrawList* draw_list = draw_data->CmdLists[n];
+        memcpy(vtx_dst, draw_list->VtxBuffer.Data, draw_list->VtxBuffer.Size * sizeof(ImDrawVert));
+        memcpy(idx_dst, draw_list->IdxBuffer.Data, draw_list->IdxBuffer.Size * sizeof(ImDrawIdx));
+        vtx_dst += draw_list->VtxBuffer.Size;
+        idx_dst += draw_list->IdxBuffer.Size;
     }
-    ctx->Unmap(bd->pVB, 0);
-    ctx->Unmap(bd->pIB, 0);
+    device->Unmap(bd->pVB, 0);
+    device->Unmap(bd->pIB, 0);
 
     // Setup orthographic projection matrix into our constant buffer
     // Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right). DisplayPos is (0,0) for single viewport apps.
     {
         D3D11_MAPPED_SUBRESOURCE mapped_resource;
-        if (ctx->Map(bd->pVertexConstantBuffer, 0, D3D11_MAP_WRITE_DISCARD, 0, &mapped_resource) != S_OK)
+        if (device->Map(bd->pVertexConstantBuffer, 0, D3D11_MAP_WRITE_DISCARD, 0, &mapped_resource) != S_OK)
             return;
         VERTEX_CONSTANT_BUFFER_DX11* constant_buffer = (VERTEX_CONSTANT_BUFFER_DX11*)mapped_resource.pData;
         float L = draw_data->DisplayPos.x;
@@ -195,7 +204,7 @@ void ImGui_ImplDX11_RenderDrawData(ImDrawData* draw_data)
             { (R+L)/(L-R),  (T+B)/(B-T),    0.5f,       1.0f },
         };
         memcpy(&constant_buffer->mvp, mvp, sizeof(mvp));
-        ctx->Unmap(bd->pVertexConstantBuffer, 0);
+        device->Unmap(bd->pVertexConstantBuffer, 0);
     }
 
     // Backup DX state that will be modified to restore it afterwards (unfortunately this is very ugly looking and verbose. Close your eyes!)
@@ -225,26 +234,34 @@ void ImGui_ImplDX11_RenderDrawData(ImDrawData* draw_data)
     };
     BACKUP_DX11_STATE old = {};
     old.ScissorRectsCount = old.ViewportsCount = D3D11_VIEWPORT_AND_SCISSORRECT_OBJECT_COUNT_PER_PIPELINE;
-    ctx->RSGetScissorRects(&old.ScissorRectsCount, old.ScissorRects);
-    ctx->RSGetViewports(&old.ViewportsCount, old.Viewports);
-    ctx->RSGetState(&old.RS);
-    ctx->OMGetBlendState(&old.BlendState, old.BlendFactor, &old.SampleMask);
-    ctx->OMGetDepthStencilState(&old.DepthStencilState, &old.StencilRef);
-    ctx->PSGetShaderResources(0, 1, &old.PSShaderResource);
-    ctx->PSGetSamplers(0, 1, &old.PSSampler);
+    device->RSGetScissorRects(&old.ScissorRectsCount, old.ScissorRects);
+    device->RSGetViewports(&old.ViewportsCount, old.Viewports);
+    device->RSGetState(&old.RS);
+    device->OMGetBlendState(&old.BlendState, old.BlendFactor, &old.SampleMask);
+    device->OMGetDepthStencilState(&old.DepthStencilState, &old.StencilRef);
+    device->PSGetShaderResources(0, 1, &old.PSShaderResource);
+    device->PSGetSamplers(0, 1, &old.PSSampler);
     old.PSInstancesCount = old.VSInstancesCount = old.GSInstancesCount = 256;
-    ctx->PSGetShader(&old.PS, old.PSInstances, &old.PSInstancesCount);
-    ctx->VSGetShader(&old.VS, old.VSInstances, &old.VSInstancesCount);
-    ctx->VSGetConstantBuffers(0, 1, &old.VSConstantBuffer);
-    ctx->GSGetShader(&old.GS, old.GSInstances, &old.GSInstancesCount);
+    device->PSGetShader(&old.PS, old.PSInstances, &old.PSInstancesCount);
+    device->VSGetShader(&old.VS, old.VSInstances, &old.VSInstancesCount);
+    device->VSGetConstantBuffers(0, 1, &old.VSConstantBuffer);
+    device->GSGetShader(&old.GS, old.GSInstances, &old.GSInstancesCount);
 
-    ctx->IAGetPrimitiveTopology(&old.PrimitiveTopology);
-    ctx->IAGetIndexBuffer(&old.IndexBuffer, &old.IndexBufferFormat, &old.IndexBufferOffset);
-    ctx->IAGetVertexBuffers(0, 1, &old.VertexBuffer, &old.VertexBufferStride, &old.VertexBufferOffset);
-    ctx->IAGetInputLayout(&old.InputLayout);
+    device->IAGetPrimitiveTopology(&old.PrimitiveTopology);
+    device->IAGetIndexBuffer(&old.IndexBuffer, &old.IndexBufferFormat, &old.IndexBufferOffset);
+    device->IAGetVertexBuffers(0, 1, &old.VertexBuffer, &old.VertexBufferStride, &old.VertexBufferOffset);
+    device->IAGetInputLayout(&old.InputLayout);
 
     // Setup desired DX state
-    ImGui_ImplDX11_SetupRenderState(draw_data, ctx);
+    ImGui_ImplDX11_SetupRenderState(draw_data, device);
+
+    // Setup render state structure (for callbacks and custom texture bindings)
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    ImGui_ImplDX11_RenderState render_state;
+    render_state.Device = bd->pd3dDevice;
+    render_state.DeviceContext = bd->pd3dDeviceContext;
+    render_state.SamplerDefault = bd->pFontSampler;
+    platform_io.Renderer_RenderState = &render_state;
 
     // Render command lists
     // (Because we merged all buffers into a single one, we maintain our own offset into them)
@@ -253,18 +270,18 @@ void ImGui_ImplDX11_RenderDrawData(ImDrawData* draw_data)
     ImVec2 clip_off = draw_data->DisplayPos;
     for (int n = 0; n < draw_data->CmdListsCount; n++)
     {
-        const ImDrawList* cmd_list = draw_data->CmdLists[n];
-        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        const ImDrawList* draw_list = draw_data->CmdLists[n];
+        for (int cmd_i = 0; cmd_i < draw_list->CmdBuffer.Size; cmd_i++)
         {
-            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            const ImDrawCmd* pcmd = &draw_list->CmdBuffer[cmd_i];
             if (pcmd->UserCallback != nullptr)
             {
                 // User callback, registered via ImDrawList::AddCallback()
                 // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.)
                 if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
-                    ImGui_ImplDX11_SetupRenderState(draw_data, ctx);
+                    ImGui_ImplDX11_SetupRenderState(draw_data, device);
                 else
-                    pcmd->UserCallback(cmd_list, pcmd);
+                    pcmd->UserCallback(draw_list, pcmd);
             }
             else
             {
@@ -276,36 +293,37 @@ void ImGui_ImplDX11_RenderDrawData(ImDrawData* draw_data)
 
                 // Apply scissor/clipping rectangle
                 const D3D11_RECT r = { (LONG)clip_min.x, (LONG)clip_min.y, (LONG)clip_max.x, (LONG)clip_max.y };
-                ctx->RSSetScissorRects(1, &r);
+                device->RSSetScissorRects(1, &r);
 
                 // Bind texture, Draw
                 ID3D11ShaderResourceView* texture_srv = (ID3D11ShaderResourceView*)pcmd->GetTexID();
-                ctx->PSSetShaderResources(0, 1, &texture_srv);
-                ctx->DrawIndexed(pcmd->ElemCount, pcmd->IdxOffset + global_idx_offset, pcmd->VtxOffset + global_vtx_offset);
+                device->PSSetShaderResources(0, 1, &texture_srv);
+                device->DrawIndexed(pcmd->ElemCount, pcmd->IdxOffset + global_idx_offset, pcmd->VtxOffset + global_vtx_offset);
             }
         }
-        global_idx_offset += cmd_list->IdxBuffer.Size;
-        global_vtx_offset += cmd_list->VtxBuffer.Size;
+        global_idx_offset += draw_list->IdxBuffer.Size;
+        global_vtx_offset += draw_list->VtxBuffer.Size;
     }
+    platform_io.Renderer_RenderState = nullptr;
 
     // Restore modified DX state
-    ctx->RSSetScissorRects(old.ScissorRectsCount, old.ScissorRects);
-    ctx->RSSetViewports(old.ViewportsCount, old.Viewports);
-    ctx->RSSetState(old.RS); if (old.RS) old.RS->Release();
-    ctx->OMSetBlendState(old.BlendState, old.BlendFactor, old.SampleMask); if (old.BlendState) old.BlendState->Release();
-    ctx->OMSetDepthStencilState(old.DepthStencilState, old.StencilRef); if (old.DepthStencilState) old.DepthStencilState->Release();
-    ctx->PSSetShaderResources(0, 1, &old.PSShaderResource); if (old.PSShaderResource) old.PSShaderResource->Release();
-    ctx->PSSetSamplers(0, 1, &old.PSSampler); if (old.PSSampler) old.PSSampler->Release();
-    ctx->PSSetShader(old.PS, old.PSInstances, old.PSInstancesCount); if (old.PS) old.PS->Release();
+    device->RSSetScissorRects(old.ScissorRectsCount, old.ScissorRects);
+    device->RSSetViewports(old.ViewportsCount, old.Viewports);
+    device->RSSetState(old.RS); if (old.RS) old.RS->Release();
+    device->OMSetBlendState(old.BlendState, old.BlendFactor, old.SampleMask); if (old.BlendState) old.BlendState->Release();
+    device->OMSetDepthStencilState(old.DepthStencilState, old.StencilRef); if (old.DepthStencilState) old.DepthStencilState->Release();
+    device->PSSetShaderResources(0, 1, &old.PSShaderResource); if (old.PSShaderResource) old.PSShaderResource->Release();
+    device->PSSetSamplers(0, 1, &old.PSSampler); if (old.PSSampler) old.PSSampler->Release();
+    device->PSSetShader(old.PS, old.PSInstances, old.PSInstancesCount); if (old.PS) old.PS->Release();
     for (UINT i = 0; i < old.PSInstancesCount; i++) if (old.PSInstances[i]) old.PSInstances[i]->Release();
-    ctx->VSSetShader(old.VS, old.VSInstances, old.VSInstancesCount); if (old.VS) old.VS->Release();
-    ctx->VSSetConstantBuffers(0, 1, &old.VSConstantBuffer); if (old.VSConstantBuffer) old.VSConstantBuffer->Release();
-    ctx->GSSetShader(old.GS, old.GSInstances, old.GSInstancesCount); if (old.GS) old.GS->Release();
+    device->VSSetShader(old.VS, old.VSInstances, old.VSInstancesCount); if (old.VS) old.VS->Release();
+    device->VSSetConstantBuffers(0, 1, &old.VSConstantBuffer); if (old.VSConstantBuffer) old.VSConstantBuffer->Release();
+    device->GSSetShader(old.GS, old.GSInstances, old.GSInstancesCount); if (old.GS) old.GS->Release();
     for (UINT i = 0; i < old.VSInstancesCount; i++) if (old.VSInstances[i]) old.VSInstances[i]->Release();
-    ctx->IASetPrimitiveTopology(old.PrimitiveTopology);
-    ctx->IASetIndexBuffer(old.IndexBuffer, old.IndexBufferFormat, old.IndexBufferOffset); if (old.IndexBuffer) old.IndexBuffer->Release();
-    ctx->IASetVertexBuffers(0, 1, &old.VertexBuffer, &old.VertexBufferStride, &old.VertexBufferOffset); if (old.VertexBuffer) old.VertexBuffer->Release();
-    ctx->IASetInputLayout(old.InputLayout); if (old.InputLayout) old.InputLayout->Release();
+    device->IASetPrimitiveTopology(old.PrimitiveTopology);
+    device->IASetIndexBuffer(old.IndexBuffer, old.IndexBufferFormat, old.IndexBufferOffset); if (old.IndexBuffer) old.IndexBuffer->Release();
+    device->IASetVertexBuffers(0, 1, &old.VertexBuffer, &old.VertexBufferStride, &old.VertexBufferOffset); if (old.VertexBuffer) old.VertexBuffer->Release();
+    device->IASetInputLayout(old.InputLayout); if (old.InputLayout) old.InputLayout->Release();
 }
 
 static void ImGui_ImplDX11_CreateFontsTexture()
@@ -352,21 +370,16 @@ static void ImGui_ImplDX11_CreateFontsTexture()
 
     // Store our identifier
     io.Fonts->SetTexID((ImTextureID)bd->pFontTextureView);
+}
 
-    // Create texture sampler
-    // (Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling)
+static void ImGui_ImplDX11_DestroyFontsTexture()
+{
+    ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
+    if (bd->pFontTextureView)
     {
-        D3D11_SAMPLER_DESC desc;
-        ZeroMemory(&desc, sizeof(desc));
-        desc.Filter = D3D11_FILTER_MIN_MAG_MIP_LINEAR;
-        desc.AddressU = D3D11_TEXTURE_ADDRESS_WRAP;
-        desc.AddressV = D3D11_TEXTURE_ADDRESS_WRAP;
-        desc.AddressW = D3D11_TEXTURE_ADDRESS_WRAP;
-        desc.MipLODBias = 0.f;
-        desc.ComparisonFunc = D3D11_COMPARISON_ALWAYS;
-        desc.MinLOD = 0.f;
-        desc.MaxLOD = 0.f;
-        bd->pd3dDevice->CreateSamplerState(&desc, &bd->pFontSampler);
+        bd->pFontTextureView->Release();
+        bd->pFontTextureView = nullptr;
+        ImGui::GetIO().Fonts->SetTexID(0); // We copied data->pFontTextureView to io.Fonts->TexID so let's clear that as well.
     }
 }
 
@@ -519,6 +532,22 @@ bool    ImGui_ImplDX11_CreateDeviceObjects()
         bd->pd3dDevice->CreateDepthStencilState(&desc, &bd->pDepthStencilState);
     }
 
+    // Create texture sampler
+    // (Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling)
+    {
+        D3D11_SAMPLER_DESC desc;
+        ZeroMemory(&desc, sizeof(desc));
+        desc.Filter = D3D11_FILTER_MIN_MAG_MIP_LINEAR;
+        desc.AddressU = D3D11_TEXTURE_ADDRESS_CLAMP;
+        desc.AddressV = D3D11_TEXTURE_ADDRESS_CLAMP;
+        desc.AddressW = D3D11_TEXTURE_ADDRESS_CLAMP;
+        desc.MipLODBias = 0.f;
+        desc.ComparisonFunc = D3D11_COMPARISON_ALWAYS;
+        desc.MinLOD = 0.f;
+        desc.MaxLOD = 0.f;
+        bd->pd3dDevice->CreateSamplerState(&desc, &bd->pFontSampler);
+    }
+
     ImGui_ImplDX11_CreateFontsTexture();
 
     return true;
@@ -530,8 +559,9 @@ void    ImGui_ImplDX11_InvalidateDeviceObjects()
     if (!bd->pd3dDevice)
         return;
 
+    ImGui_ImplDX11_DestroyFontsTexture();
+
     if (bd->pFontSampler)           { bd->pFontSampler->Release(); bd->pFontSampler = nullptr; }
-    if (bd->pFontTextureView)       { bd->pFontTextureView->Release(); bd->pFontTextureView = nullptr; ImGui::GetIO().Fonts->SetTexID(0); } // We copied data->pFontTextureView to io.Fonts->TexID so let's clear that as well.
     if (bd->pIB)                    { bd->pIB->Release(); bd->pIB = nullptr; }
     if (bd->pVB)                    { bd->pVB->Release(); bd->pVB = nullptr; }
     if (bd->pBlendState)            { bd->pBlendState->Release(); bd->pBlendState = nullptr; }
@@ -554,6 +584,7 @@ bool    ImGui_ImplDX11_Init(ID3D11Device* device, ID3D11DeviceContext* device_co
     io.BackendRendererUserData = (void*)bd;
     io.BackendRendererName = "imgui_impl_dx11";
     io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset;  // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
+    io.BackendFlags |= ImGuiBackendFlags_RendererHasViewports;  // We can create multi-viewports on the Renderer side (optional)
 
     // Get factory from device
     IDXGIDevice* pDXGIDevice = nullptr;
@@ -573,6 +604,8 @@ bool    ImGui_ImplDX11_Init(ID3D11Device* device, ID3D11DeviceContext* device_co
     bd->pd3dDevice->AddRef();
     bd->pd3dDeviceContext->AddRef();
 
+    ImGui_ImplDX11_InitMultiViewportSupport();
+
     return true;
 }
 
@@ -582,13 +615,14 @@ void ImGui_ImplDX11_Shutdown()
     IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
     ImGuiIO& io = ImGui::GetIO();
 
+    ImGui_ImplDX11_ShutdownMultiViewportSupport();
     ImGui_ImplDX11_InvalidateDeviceObjects();
     if (bd->pFactory)             { bd->pFactory->Release(); }
     if (bd->pd3dDevice)           { bd->pd3dDevice->Release(); }
     if (bd->pd3dDeviceContext)    { bd->pd3dDeviceContext->Release(); }
     io.BackendRendererName = nullptr;
     io.BackendRendererUserData = nullptr;
-    io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset;
+    io.BackendFlags &= ~(ImGuiBackendFlags_RendererHasVtxOffset | ImGuiBackendFlags_RendererHasViewports);
     IM_DELETE(bd);
 }
 
@@ -601,6 +635,129 @@ void ImGui_ImplDX11_NewFrame()
         ImGui_ImplDX11_CreateDeviceObjects();
 }
 
+//--------------------------------------------------------------------------------------------------------
+// MULTI-VIEWPORT / PLATFORM INTERFACE SUPPORT
+// This is an _advanced_ and _optional_ feature, allowing the backend to create and handle multiple viewports simultaneously.
+// If you are new to dear imgui or creating a new binding for dear imgui, it is recommended that you completely ignore this section first..
+//--------------------------------------------------------------------------------------------------------
+
+// Helper structure we store in the void* RendererUserData field of each ImGuiViewport to easily retrieve our backend data.
+struct ImGui_ImplDX11_ViewportData
+{
+    IDXGISwapChain*                 SwapChain;
+    ID3D11RenderTargetView*         RTView;
+
+    ImGui_ImplDX11_ViewportData()   { SwapChain = nullptr; RTView = nullptr; }
+    ~ImGui_ImplDX11_ViewportData()  { IM_ASSERT(SwapChain == nullptr && RTView == nullptr); }
+};
+
+static void ImGui_ImplDX11_CreateWindow(ImGuiViewport* viewport)
+{
+    ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
+    ImGui_ImplDX11_ViewportData* vd = IM_NEW(ImGui_ImplDX11_ViewportData)();
+    viewport->RendererUserData = vd;
+
+    // PlatformHandleRaw should always be a HWND, whereas PlatformHandle might be a higher-level handle (e.g. GLFWWindow*, SDL_Window*).
+    // Some backends will leave PlatformHandleRaw == 0, in which case we assume PlatformHandle will contain the HWND.
+    HWND hwnd = viewport->PlatformHandleRaw ? (HWND)viewport->PlatformHandleRaw : (HWND)viewport->PlatformHandle;
+    IM_ASSERT(hwnd != 0);
+
+    // Create swap chain
+    DXGI_SWAP_CHAIN_DESC sd;
+    ZeroMemory(&sd, sizeof(sd));
+    sd.BufferDesc.Width = (UINT)viewport->Size.x;
+    sd.BufferDesc.Height = (UINT)viewport->Size.y;
+    sd.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
+    sd.SampleDesc.Count = 1;
+    sd.SampleDesc.Quality = 0;
+    sd.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
+    sd.BufferCount = 1;
+    sd.OutputWindow = hwnd;
+    sd.Windowed = TRUE;
+    sd.SwapEffect = DXGI_SWAP_EFFECT_DISCARD;
+    sd.Flags = 0;
+
+    IM_ASSERT(vd->SwapChain == nullptr && vd->RTView == nullptr);
+    bd->pFactory->CreateSwapChain(bd->pd3dDevice, &sd, &vd->SwapChain);
+
+    // Create the render target
+    if (vd->SwapChain)
+    {
+        ID3D11Texture2D* pBackBuffer;
+        vd->SwapChain->GetBuffer(0, IID_PPV_ARGS(&pBackBuffer));
+        bd->pd3dDevice->CreateRenderTargetView(pBackBuffer, nullptr, &vd->RTView);
+        pBackBuffer->Release();
+    }
+}
+
+static void ImGui_ImplDX11_DestroyWindow(ImGuiViewport* viewport)
+{
+    // The main viewport (owned by the application) will always have RendererUserData == nullptr since we didn't create the data for it.
+    if (ImGui_ImplDX11_ViewportData* vd = (ImGui_ImplDX11_ViewportData*)viewport->RendererUserData)
+    {
+        if (vd->SwapChain)
+            vd->SwapChain->Release();
+        vd->SwapChain = nullptr;
+        if (vd->RTView)
+            vd->RTView->Release();
+        vd->RTView = nullptr;
+        IM_DELETE(vd);
+    }
+    viewport->RendererUserData = nullptr;
+}
+
+static void ImGui_ImplDX11_SetWindowSize(ImGuiViewport* viewport, ImVec2 size)
+{
+    ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
+    ImGui_ImplDX11_ViewportData* vd = (ImGui_ImplDX11_ViewportData*)viewport->RendererUserData;
+    if (vd->RTView)
+    {
+        vd->RTView->Release();
+        vd->RTView = nullptr;
+    }
+    if (vd->SwapChain)
+    {
+        ID3D11Texture2D* pBackBuffer = nullptr;
+        vd->SwapChain->ResizeBuffers(0, (UINT)size.x, (UINT)size.y, DXGI_FORMAT_UNKNOWN, 0);
+        vd->SwapChain->GetBuffer(0, IID_PPV_ARGS(&pBackBuffer));
+        if (pBackBuffer == nullptr) { fprintf(stderr, "ImGui_ImplDX11_SetWindowSize() failed creating buffers.\n"); return; }
+        bd->pd3dDevice->CreateRenderTargetView(pBackBuffer, nullptr, &vd->RTView);
+        pBackBuffer->Release();
+    }
+}
+
+static void ImGui_ImplDX11_RenderWindow(ImGuiViewport* viewport, void*)
+{
+    ImGui_ImplDX11_Data* bd = ImGui_ImplDX11_GetBackendData();
+    ImGui_ImplDX11_ViewportData* vd = (ImGui_ImplDX11_ViewportData*)viewport->RendererUserData;
+    ImVec4 clear_color = ImVec4(0.0f, 0.0f, 0.0f, 1.0f);
+    bd->pd3dDeviceContext->OMSetRenderTargets(1, &vd->RTView, nullptr);
+    if (!(viewport->Flags & ImGuiViewportFlags_NoRendererClear))
+        bd->pd3dDeviceContext->ClearRenderTargetView(vd->RTView, (float*)&clear_color);
+    ImGui_ImplDX11_RenderDrawData(viewport->DrawData);
+}
+
+static void ImGui_ImplDX11_SwapBuffers(ImGuiViewport* viewport, void*)
+{
+    ImGui_ImplDX11_ViewportData* vd = (ImGui_ImplDX11_ViewportData*)viewport->RendererUserData;
+    vd->SwapChain->Present(0, 0); // Present without vsync
+}
+
+static void ImGui_ImplDX11_InitMultiViewportSupport()
+{
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    platform_io.Renderer_CreateWindow = ImGui_ImplDX11_CreateWindow;
+    platform_io.Renderer_DestroyWindow = ImGui_ImplDX11_DestroyWindow;
+    platform_io.Renderer_SetWindowSize = ImGui_ImplDX11_SetWindowSize;
+    platform_io.Renderer_RenderWindow = ImGui_ImplDX11_RenderWindow;
+    platform_io.Renderer_SwapBuffers = ImGui_ImplDX11_SwapBuffers;
+}
+
+static void ImGui_ImplDX11_ShutdownMultiViewportSupport()
+{
+    ImGui::DestroyPlatformWindows();
+}
+
 //-----------------------------------------------------------------------------
 
 #endif // #ifndef IMGUI_DISABLE

backends/imgui_impl_dx11.h

@@ -3,7 +3,9 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'ID3D11ShaderResourceView*' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
+//  [X] Renderer: Expose selected render state for draw callbacks to use. Access in '(ImGui_ImplXXXX_RenderState*)GetPlatformIO().Renderer_RenderState'.
+//  [X] Renderer: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -19,14 +21,26 @@
 
 struct ID3D11Device;
 struct ID3D11DeviceContext;
+struct ID3D11SamplerState;
 
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
 IMGUI_IMPL_API bool     ImGui_ImplDX11_Init(ID3D11Device* device, ID3D11DeviceContext* device_context);
 IMGUI_IMPL_API void     ImGui_ImplDX11_Shutdown();
 IMGUI_IMPL_API void     ImGui_ImplDX11_NewFrame();
 IMGUI_IMPL_API void     ImGui_ImplDX11_RenderDrawData(ImDrawData* draw_data);
 
 // Use if you want to reset your rendering device without losing Dear ImGui state.
-IMGUI_IMPL_API void     ImGui_ImplDX11_InvalidateDeviceObjects();
 IMGUI_IMPL_API bool     ImGui_ImplDX11_CreateDeviceObjects();
+IMGUI_IMPL_API void     ImGui_ImplDX11_InvalidateDeviceObjects();
+
+// [BETA] Selected render state data shared with callbacks.
+// This is temporarily stored in GetPlatformIO().Renderer_RenderState during the ImGui_ImplDX11_RenderDrawData() call.
+// (Please open an issue if you feel you need access to more data)
+struct ImGui_ImplDX11_RenderState
+{
+    ID3D11Device*           Device;
+    ID3D11DeviceContext*    DeviceContext;
+    ID3D11SamplerState*     SamplerDefault;
+};
 
 #endif // #ifndef IMGUI_DISABLE

backends/imgui_impl_dx12.cpp

@@ -3,15 +3,13 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'D3D12_GPU_DESCRIPTOR_HANDLE' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
+//  [X] Renderer: Expose selected render state for draw callbacks to use. Access in '(ImGui_ImplXXXX_RenderState*)GetPlatformIO().Renderer_RenderState'.
+//  [X] Renderer: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
+//      FIXME: The transition from removing a viewport and moving the window in an existing hosted viewport tends to flicker.
 
-// Important: to compile on 32-bit systems, this backend requires code to be compiled with '#define ImTextureID ImU64'.
-// This is because we need ImTextureID to carry a 64-bit value and by default ImTextureID is defined as void*.
-// To build this on 32-bit systems:
-// - [Solution 1] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'ImTextureID=ImU64' (this is what we do in the 'example_win32_direct12/example_win32_direct12.vcxproj' project file)
-// - [Solution 2] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'IMGUI_USER_CONFIG="my_imgui_config.h"' and inside 'my_imgui_config.h' add '#define ImTextureID ImU64' and as many other options as you like.
-// - [Solution 3] IDE/msbuild: edit imconfig.h and add '#define ImTextureID ImU64' (prefer solution 2 to create your own config file!)
-// - [Solution 4] command-line: add '/D ImTextureID=ImU64' to your cl.exe command-line (this is what we do in the example_win32_direct12/build_win32.bat file)
+// The aim of imgui_impl_dx12.h/.cpp is to be usable in your engine without any modification.
+// IF YOU FEEL YOU NEED TO MAKE ANY CHANGE TO THIS CODE, please share them and your feedback at https://github.com/ocornut/imgui/
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -23,6 +21,14 @@
 
 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
+//  2024-XX-XX: Platform: Added support for multiple windows via the ImGuiPlatformIO interface.
+//  2024-12-09: DirectX12: Let user specifies the DepthStencilView format by setting ImGui_ImplDX12_InitInfo::DSVFormat. 
+//  2024-11-15: DirectX12: *BREAKING CHANGE* Changed ImGui_ImplDX12_Init() signature to take a ImGui_ImplDX12_InitInfo struct. Legacy ImGui_ImplDX12_Init() signature is still supported (will obsolete).
+//  2024-11-15: DirectX12: *BREAKING CHANGE* User is now required to pass function pointers to allocate/free SRV Descriptors. We provide convenience legacy fields to pass a single descriptor, matching the old API, but upcoming features will want multiple.
+//  2024-10-23: DirectX12: Unmap() call specify written range. The range is informational and may be used by debug tools.
+//  2024-10-07: DirectX12: Changed default texture sampler to Clamp instead of Repeat/Wrap.
+//  2024-10-07: DirectX12: Expose selected render state in ImGui_ImplDX12_RenderState, which you can access in 'void* platform_io.Renderer_RenderState' during draw callbacks.
+//  2024-10-07: DirectX12: Compiling with '#define ImTextureID=ImU64' is unnecessary now that dear imgui defaults ImTextureID to u64 instead of void*.
 //  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
 //  2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
 //  2021-05-19: DirectX12: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement)
@@ -53,24 +59,32 @@
 #pragma comment(lib, "d3dcompiler") // Automatically link with d3dcompiler.lib as we are using D3DCompile() below.
 #endif
 
-// DirectX data
+// DirectX12 data
 struct ImGui_ImplDX12_RenderBuffers;
+
+struct ImGui_ImplDX12_Texture
+{
+    ID3D12Resource*             pTextureResource;
+    D3D12_CPU_DESCRIPTOR_HANDLE hFontSrvCpuDescHandle;
+    D3D12_GPU_DESCRIPTOR_HANDLE hFontSrvGpuDescHandle;
+
+    ImGui_ImplDX12_Texture()    { memset((void*)this, 0, sizeof(*this)); }
+};
+
 struct ImGui_ImplDX12_Data
 {
+    ImGui_ImplDX12_InitInfo     InitInfo;
     ID3D12Device*               pd3dDevice;
     ID3D12RootSignature*        pRootSignature;
     ID3D12PipelineState*        pPipelineState;
     DXGI_FORMAT                 RTVFormat;
-    ID3D12Resource*             pFontTextureResource;
-    D3D12_CPU_DESCRIPTOR_HANDLE hFontSrvCpuDescHandle;
-    D3D12_GPU_DESCRIPTOR_HANDLE hFontSrvGpuDescHandle;
+    DXGI_FORMAT                 DSVFormat;
     ID3D12DescriptorHeap*       pd3dSrvDescHeap;
     UINT                        numFramesInFlight;
+    ImGui_ImplDX12_Texture      FontTexture;
+    bool                        LegacySingleDescriptorUsed;
 
-    ImGui_ImplDX12_RenderBuffers* pFrameResources;
-    UINT                        frameIndex;
-
-    ImGui_ImplDX12_Data()       { memset((void*)this, 0, sizeof(*this)); frameIndex = UINT_MAX; }
+    ImGui_ImplDX12_Data()       { memset((void*)this, 0, sizeof(*this)); }
 };
 
 // Backend data stored in io.BackendRendererUserData to allow support for multiple Dear ImGui contexts
@@ -89,13 +103,90 @@ struct ImGui_ImplDX12_RenderBuffers
     int                 VertexBufferSize;
 };
 
+// Buffers used for secondary viewports created by the multi-viewports systems
+struct ImGui_ImplDX12_FrameContext
+{
+    ID3D12CommandAllocator*         CommandAllocator;
+    ID3D12Resource*                 RenderTarget;
+    D3D12_CPU_DESCRIPTOR_HANDLE     RenderTargetCpuDescriptors;
+};
+
+// Helper structure we store in the void* RendererUserData field of each ImGuiViewport to easily retrieve our backend data.
+// Main viewport created by application will only use the Resources field.
+// Secondary viewports created by this backend will use all the fields (including Window fields),
+struct ImGui_ImplDX12_ViewportData
+{
+    // Window
+    ID3D12CommandQueue*             CommandQueue;
+    ID3D12GraphicsCommandList*      CommandList;
+    ID3D12DescriptorHeap*           RtvDescHeap;
+    IDXGISwapChain3*                SwapChain;
+    ID3D12Fence*                    Fence;
+    UINT64                          FenceSignaledValue;
+    HANDLE                          FenceEvent;
+    UINT                            NumFramesInFlight;
+    ImGui_ImplDX12_FrameContext*    FrameCtx;
+
+    // Render buffers
+    UINT                            FrameIndex;
+    ImGui_ImplDX12_RenderBuffers*   FrameRenderBuffers;
+
+    ImGui_ImplDX12_ViewportData(UINT num_frames_in_flight)
+    {
+        CommandQueue = nullptr;
+        CommandList = nullptr;
+        RtvDescHeap = nullptr;
+        SwapChain = nullptr;
+        Fence = nullptr;
+        FenceSignaledValue = 0;
+        FenceEvent = nullptr;
+        NumFramesInFlight = num_frames_in_flight;
+        FrameCtx = new ImGui_ImplDX12_FrameContext[NumFramesInFlight];
+        FrameIndex = UINT_MAX;
+        FrameRenderBuffers = new ImGui_ImplDX12_RenderBuffers[NumFramesInFlight];
+
+        for (UINT i = 0; i < NumFramesInFlight; ++i)
+        {
+            FrameCtx[i].CommandAllocator = nullptr;
+            FrameCtx[i].RenderTarget = nullptr;
+
+            // Create buffers with a default size (they will later be grown as needed)
+            FrameRenderBuffers[i].IndexBuffer = nullptr;
+            FrameRenderBuffers[i].VertexBuffer = nullptr;
+            FrameRenderBuffers[i].VertexBufferSize = 5000;
+            FrameRenderBuffers[i].IndexBufferSize = 10000;
+        }
+    }
+    ~ImGui_ImplDX12_ViewportData()
+    {
+        IM_ASSERT(CommandQueue == nullptr && CommandList == nullptr);
+        IM_ASSERT(RtvDescHeap == nullptr);
+        IM_ASSERT(SwapChain == nullptr);
+        IM_ASSERT(Fence == nullptr);
+        IM_ASSERT(FenceEvent == nullptr);
+
+        for (UINT i = 0; i < NumFramesInFlight; ++i)
+        {
+            IM_ASSERT(FrameCtx[i].CommandAllocator == nullptr && FrameCtx[i].RenderTarget == nullptr);
+            IM_ASSERT(FrameRenderBuffers[i].IndexBuffer == nullptr && FrameRenderBuffers[i].VertexBuffer == nullptr);
+        }
+
+        delete[] FrameCtx; FrameCtx = nullptr;
+        delete[] FrameRenderBuffers; FrameRenderBuffers = nullptr;
+    }
+};
+
 struct VERTEX_CONSTANT_BUFFER_DX12
 {
     float   mvp[4][4];
 };
 
+// Forward Declarations
+static void ImGui_ImplDX12_InitPlatformInterface();
+static void ImGui_ImplDX12_ShutdownPlatformInterface();
+
 // Functions
-static void ImGui_ImplDX12_SetupRenderState(ImDrawData* draw_data, ID3D12GraphicsCommandList* ctx, ImGui_ImplDX12_RenderBuffers* fr)
+static void ImGui_ImplDX12_SetupRenderState(ImDrawData* draw_data, ID3D12GraphicsCommandList* command_list, ImGui_ImplDX12_RenderBuffers* fr)
 {
     ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
 
@@ -125,7 +216,7 @@ static void ImGui_ImplDX12_SetupRenderState(ImDrawData* draw_data, ID3D12Graphic
     vp.MinDepth = 0.0f;
     vp.MaxDepth = 1.0f;
     vp.TopLeftX = vp.TopLeftY = 0.0f;
-    ctx->RSSetViewports(1, &vp);
+    command_list->RSSetViewports(1, &vp);
 
     // Bind shader and vertex buffers
     unsigned int stride = sizeof(ImDrawVert);
@@ -135,21 +226,21 @@ static void ImGui_ImplDX12_SetupRenderState(ImDrawData* draw_data, ID3D12Graphic
     vbv.BufferLocation = fr->VertexBuffer->GetGPUVirtualAddress() + offset;
     vbv.SizeInBytes = fr->VertexBufferSize * stride;
     vbv.StrideInBytes = stride;
-    ctx->IASetVertexBuffers(0, 1, &vbv);
+    command_list->IASetVertexBuffers(0, 1, &vbv);
     D3D12_INDEX_BUFFER_VIEW ibv;
     memset(&ibv, 0, sizeof(D3D12_INDEX_BUFFER_VIEW));
     ibv.BufferLocation = fr->IndexBuffer->GetGPUVirtualAddress();
     ibv.SizeInBytes = fr->IndexBufferSize * sizeof(ImDrawIdx);
     ibv.Format = sizeof(ImDrawIdx) == 2 ? DXGI_FORMAT_R16_UINT : DXGI_FORMAT_R32_UINT;
-    ctx->IASetIndexBuffer(&ibv);
-    ctx->IASetPrimitiveTopology(D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
-    ctx->SetPipelineState(bd->pPipelineState);
-    ctx->SetGraphicsRootSignature(bd->pRootSignature);
-    ctx->SetGraphicsRoot32BitConstants(0, 16, &vertex_constant_buffer, 0);
+    command_list->IASetIndexBuffer(&ibv);
+    command_list->IASetPrimitiveTopology(D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST);
+    command_list->SetPipelineState(bd->pPipelineState);
+    command_list->SetGraphicsRootSignature(bd->pRootSignature);
+    command_list->SetGraphicsRoot32BitConstants(0, 16, &vertex_constant_buffer, 0);
 
     // Setup blend factor
     const float blend_factor[4] = { 0.f, 0.f, 0.f, 0.f };
-    ctx->OMSetBlendFactor(blend_factor);
+    command_list->OMSetBlendFactor(blend_factor);
 }
 
 template<typename T>
@@ -161,17 +252,16 @@ static inline void SafeRelease(T*& res)
 }
 
 // Render function
-void ImGui_ImplDX12_RenderDrawData(ImDrawData* draw_data, ID3D12GraphicsCommandList* ctx)
+void ImGui_ImplDX12_RenderDrawData(ImDrawData* draw_data, ID3D12GraphicsCommandList* command_list)
 {
     // Avoid rendering when minimized
     if (draw_data->DisplaySize.x <= 0.0f || draw_data->DisplaySize.y <= 0.0f)
         return;
 
-    // FIXME: I'm assuming that this only gets called once per frame!
-    // If not, we can't just re-allocate the IB or VB, we'll have to do a proper allocator.
     ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
-    bd->frameIndex = bd->frameIndex + 1;
-    ImGui_ImplDX12_RenderBuffers* fr = &bd->pFrameResources[bd->frameIndex % bd->numFramesInFlight];
+    ImGui_ImplDX12_ViewportData* vd = (ImGui_ImplDX12_ViewportData*)draw_data->OwnerViewport->RendererUserData;
+    vd->FrameIndex++;
+    ImGui_ImplDX12_RenderBuffers* fr = &vd->FrameRenderBuffers[vd->FrameIndex % bd->numFramesInFlight];
 
     // Create and grow vertex/index buffers if needed
     if (fr->VertexBuffer == nullptr || fr->VertexBufferSize < draw_data->TotalVtxCount)
@@ -222,9 +312,9 @@ void ImGui_ImplDX12_RenderDrawData(ImDrawData* draw_data, ID3D12GraphicsCommandL
     }
 
     // Upload vertex/index data into a single contiguous GPU buffer
+    // During Map() we specify a null read range (as per DX12 API, this is informational and for tooling only)
     void* vtx_resource, *idx_resource;
-    D3D12_RANGE range;
-    memset(&range, 0, sizeof(D3D12_RANGE));
+    D3D12_RANGE range = { 0, 0 };
     if (fr->VertexBuffer->Map(0, &range, &vtx_resource) != S_OK)
         return;
     if (fr->IndexBuffer->Map(0, &range, &idx_resource) != S_OK)
@@ -233,17 +323,30 @@ void ImGui_ImplDX12_RenderDrawData(ImDrawData* draw_data, ID3D12GraphicsCommandL
     ImDrawIdx* idx_dst = (ImDrawIdx*)idx_resource;
     for (int n = 0; n < draw_data->CmdListsCount; n++)
     {
-        const ImDrawList* cmd_list = draw_data->CmdLists[n];
-        memcpy(vtx_dst, cmd_list->VtxBuffer.Data, cmd_list->VtxBuffer.Size * sizeof(ImDrawVert));
-        memcpy(idx_dst, cmd_list->IdxBuffer.Data, cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx));
-        vtx_dst += cmd_list->VtxBuffer.Size;
-        idx_dst += cmd_list->IdxBuffer.Size;
+        const ImDrawList* draw_list = draw_data->CmdLists[n];
+        memcpy(vtx_dst, draw_list->VtxBuffer.Data, draw_list->VtxBuffer.Size * sizeof(ImDrawVert));
+        memcpy(idx_dst, draw_list->IdxBuffer.Data, draw_list->IdxBuffer.Size * sizeof(ImDrawIdx));
+        vtx_dst += draw_list->VtxBuffer.Size;
+        idx_dst += draw_list->IdxBuffer.Size;
     }
+
+    // During Unmap() we specify the written range (as per DX12 API, this is informational and for tooling only)
+    range.End = (SIZE_T)((intptr_t)vtx_dst - (intptr_t)vtx_resource);
+    IM_ASSERT(range.End == draw_data->TotalVtxCount * sizeof(ImDrawVert));
     fr->VertexBuffer->Unmap(0, &range);
+    range.End = (SIZE_T)((intptr_t)idx_dst - (intptr_t)idx_resource);
+    IM_ASSERT(range.End == draw_data->TotalIdxCount * sizeof(ImDrawIdx));
     fr->IndexBuffer->Unmap(0, &range);
 
     // Setup desired DX state
-    ImGui_ImplDX12_SetupRenderState(draw_data, ctx, fr);
+    ImGui_ImplDX12_SetupRenderState(draw_data, command_list, fr);
+
+    // Setup render state structure (for callbacks and custom texture bindings)
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    ImGui_ImplDX12_RenderState render_state;
+    render_state.Device = bd->pd3dDevice;
+    render_state.CommandList = command_list;
+    platform_io.Renderer_RenderState = &render_state;
 
     // Render command lists
     // (Because we merged all buffers into a single one, we maintain our own offset into them)
@@ -252,18 +355,18 @@ void ImGui_ImplDX12_RenderDrawData(ImDrawData* draw_data, ID3D12GraphicsCommandL
     ImVec2 clip_off = draw_data->DisplayPos;
     for (int n = 0; n < draw_data->CmdListsCount; n++)
     {
-        const ImDrawList* cmd_list = draw_data->CmdLists[n];
-        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        const ImDrawList* draw_list = draw_data->CmdLists[n];
+        for (int cmd_i = 0; cmd_i < draw_list->CmdBuffer.Size; cmd_i++)
         {
-            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            const ImDrawCmd* pcmd = &draw_list->CmdBuffer[cmd_i];
             if (pcmd->UserCallback != nullptr)
             {
                 // User callback, registered via ImDrawList::AddCallback()
                 // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.)
                 if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
-                    ImGui_ImplDX12_SetupRenderState(draw_data, ctx, fr);
+                    ImGui_ImplDX12_SetupRenderState(draw_data, command_list, fr);
                 else
-                    pcmd->UserCallback(cmd_list, pcmd);
+                    pcmd->UserCallback(draw_list, pcmd);
             }
             else
             {
@@ -273,18 +376,21 @@ void ImGui_ImplDX12_RenderDrawData(ImDrawData* draw_data, ID3D12GraphicsCommandL
                 if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
                     continue;
 
-                // Apply Scissor/clipping rectangle, Bind texture, Draw
+                // Apply scissor/clipping rectangle
                 const D3D12_RECT r = { (LONG)clip_min.x, (LONG)clip_min.y, (LONG)clip_max.x, (LONG)clip_max.y };
+                command_list->RSSetScissorRects(1, &r);
+
+                // Bind texture, Draw
                 D3D12_GPU_DESCRIPTOR_HANDLE texture_handle = {};
                 texture_handle.ptr = (UINT64)pcmd->GetTexID();
-                ctx->SetGraphicsRootDescriptorTable(1, texture_handle);
-                ctx->RSSetScissorRects(1, &r);
-                ctx->DrawIndexedInstanced(pcmd->ElemCount, 1, pcmd->IdxOffset + global_idx_offset, pcmd->VtxOffset + global_vtx_offset, 0);
+                command_list->SetGraphicsRootDescriptorTable(1, texture_handle);
+                command_list->DrawIndexedInstanced(pcmd->ElemCount, 1, pcmd->IdxOffset + global_idx_offset, pcmd->VtxOffset + global_vtx_offset, 0);
             }
         }
-        global_idx_offset += cmd_list->IdxBuffer.Size;
-        global_vtx_offset += cmd_list->VtxBuffer.Size;
+        global_idx_offset += draw_list->IdxBuffer.Size;
+        global_vtx_offset += draw_list->VtxBuffer.Size;
     }
+    platform_io.Renderer_RenderState = nullptr;
 }
 
 static void ImGui_ImplDX12_CreateFontsTexture()
@@ -297,6 +403,7 @@ static void ImGui_ImplDX12_CreateFontsTexture()
     io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);
 
     // Upload texture to graphics system
+    ImGui_ImplDX12_Texture* font_tex = &bd->FontTexture;
     {
         D3D12_HEAP_PROPERTIES props;
         memset(&props, 0, sizeof(D3D12_HEAP_PROPERTIES));
@@ -427,21 +534,13 @@ static void ImGui_ImplDX12_CreateFontsTexture()
         srvDesc.Texture2D.MipLevels = desc.MipLevels;
         srvDesc.Texture2D.MostDetailedMip = 0;
         srvDesc.Shader4ComponentMapping = D3D12_DEFAULT_SHADER_4_COMPONENT_MAPPING;
-        bd->pd3dDevice->CreateShaderResourceView(pTexture, &srvDesc, bd->hFontSrvCpuDescHandle);
-        SafeRelease(bd->pFontTextureResource);
-        bd->pFontTextureResource = pTexture;
+        bd->pd3dDevice->CreateShaderResourceView(pTexture, &srvDesc, font_tex->hFontSrvCpuDescHandle);
+        SafeRelease(font_tex->pTextureResource);
+        font_tex->pTextureResource = pTexture;
     }
 
     // Store our identifier
-    // READ THIS IF THE STATIC_ASSERT() TRIGGERS:
-    // - Important: to compile on 32-bit systems, this backend requires code to be compiled with '#define ImTextureID ImU64'.
-    // - This is because we need ImTextureID to carry a 64-bit value and by default ImTextureID is defined as void*.
-    // [Solution 1] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'ImTextureID=ImU64' (this is what we do in the 'example_win32_direct12/example_win32_direct12.vcxproj' project file)
-    // [Solution 2] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'IMGUI_USER_CONFIG="my_imgui_config.h"' and inside 'my_imgui_config.h' add '#define ImTextureID ImU64' and as many other options as you like.
-    // [Solution 3] IDE/msbuild: edit imconfig.h and add '#define ImTextureID ImU64' (prefer solution 2 to create your own config file!)
-    // [Solution 4] command-line: add '/D ImTextureID=ImU64' to your cl.exe command-line (this is what we do in the example_win32_direct12/build_win32.bat file)
-    static_assert(sizeof(ImTextureID) >= sizeof(bd->hFontSrvGpuDescHandle.ptr), "Can't pack descriptor handle into TexID, 32-bit not supported yet.");
-    io.Fonts->SetTexID((ImTextureID)bd->hFontSrvGpuDescHandle.ptr);
+    io.Fonts->SetTexID((ImTextureID)font_tex->hFontSrvGpuDescHandle.ptr);
 }
 
 bool    ImGui_ImplDX12_CreateDeviceObjects()
@@ -477,9 +576,9 @@ bool    ImGui_ImplDX12_CreateDeviceObjects()
         // Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling.
         D3D12_STATIC_SAMPLER_DESC staticSampler = {};
         staticSampler.Filter = D3D12_FILTER_MIN_MAG_MIP_LINEAR;
-        staticSampler.AddressU = D3D12_TEXTURE_ADDRESS_MODE_WRAP;
-        staticSampler.AddressV = D3D12_TEXTURE_ADDRESS_MODE_WRAP;
-        staticSampler.AddressW = D3D12_TEXTURE_ADDRESS_MODE_WRAP;
+        staticSampler.AddressU = D3D12_TEXTURE_ADDRESS_MODE_CLAMP;
+        staticSampler.AddressV = D3D12_TEXTURE_ADDRESS_MODE_CLAMP;
+        staticSampler.AddressW = D3D12_TEXTURE_ADDRESS_MODE_CLAMP;
         staticSampler.MipLODBias = 0.f;
         staticSampler.MaxAnisotropy = 0;
         staticSampler.ComparisonFunc = D3D12_COMPARISON_FUNC_ALWAYS;
@@ -549,6 +648,7 @@ bool    ImGui_ImplDX12_CreateDeviceObjects()
     psoDesc.SampleMask = UINT_MAX;
     psoDesc.NumRenderTargets = 1;
     psoDesc.RTVFormats[0] = bd->RTVFormat;
+    psoDesc.DSVFormat = bd->DSVFormat;
     psoDesc.SampleDesc.Count = 1;
     psoDesc.Flags = D3D12_PIPELINE_STATE_FLAG_NONE;
 
@@ -678,6 +778,13 @@ bool    ImGui_ImplDX12_CreateDeviceObjects()
     return true;
 }
 
+static void ImGui_ImplDX12_DestroyRenderBuffers(ImGui_ImplDX12_RenderBuffers* render_buffers)
+{
+    SafeRelease(render_buffers->IndexBuffer);
+    SafeRelease(render_buffers->VertexBuffer);
+    render_buffers->IndexBufferSize = render_buffers->VertexBufferSize = 0;
+}
+
 void    ImGui_ImplDX12_InvalidateDeviceObjects()
 {
     ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
@@ -687,19 +794,15 @@ void    ImGui_ImplDX12_InvalidateDeviceObjects()
     ImGuiIO& io = ImGui::GetIO();
     SafeRelease(bd->pRootSignature);
     SafeRelease(bd->pPipelineState);
-    SafeRelease(bd->pFontTextureResource);
-    io.Fonts->SetTexID(0); // We copied bd->pFontTextureView to io.Fonts->TexID so let's clear that as well.
 
-    for (UINT i = 0; i < bd->numFramesInFlight; i++)
-    {
-        ImGui_ImplDX12_RenderBuffers* fr = &bd->pFrameResources[i];
-        SafeRelease(fr->IndexBuffer);
-        SafeRelease(fr->VertexBuffer);
-    }
+    // Free SRV descriptor used by texture
+    ImGui_ImplDX12_Texture* font_tex = &bd->FontTexture;
+    bd->InitInfo.SrvDescriptorFreeFn(&bd->InitInfo, font_tex->hFontSrvCpuDescHandle, font_tex->hFontSrvGpuDescHandle);
+    SafeRelease(font_tex->pTextureResource);
+    io.Fonts->SetTexID(0); // We copied bd->hFontSrvGpuDescHandle to io.Fonts->TexID so let's clear that as well.
 }
 
-bool ImGui_ImplDX12_Init(ID3D12Device* device, int num_frames_in_flight, DXGI_FORMAT rtv_format, ID3D12DescriptorHeap* cbv_srv_heap,
-                         D3D12_CPU_DESCRIPTOR_HANDLE font_srv_cpu_desc_handle, D3D12_GPU_DESCRIPTOR_HANDLE font_srv_gpu_desc_handle)
+bool ImGui_ImplDX12_Init(ImGui_ImplDX12_InitInfo* init_info)
 {
     ImGuiIO& io = ImGui::GetIO();
     IMGUI_CHECKVERSION();
@@ -707,44 +810,96 @@ bool ImGui_ImplDX12_Init(ID3D12Device* device, int num_frames_in_flight, DXGI_FO
 
     // Setup backend capabilities flags
     ImGui_ImplDX12_Data* bd = IM_NEW(ImGui_ImplDX12_Data)();
+    bd->InitInfo = *init_info; // Deep copy
+    init_info = &bd->InitInfo;
+
+    bd->pd3dDevice = init_info->Device;
+    bd->RTVFormat = init_info->RTVFormat;
+    bd->DSVFormat = init_info->DSVFormat;
+    bd->numFramesInFlight = init_info->NumFramesInFlight;
+    bd->pd3dSrvDescHeap = init_info->SrvDescriptorHeap;
+
     io.BackendRendererUserData = (void*)bd;
     io.BackendRendererName = "imgui_impl_dx12";
     io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset;  // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
+    io.BackendFlags |= ImGuiBackendFlags_RendererHasViewports;  // We can create multi-viewports on the Renderer side (optional)
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+        ImGui_ImplDX12_InitPlatformInterface();
 
-    bd->pd3dDevice = device;
-    bd->RTVFormat = rtv_format;
-    bd->hFontSrvCpuDescHandle = font_srv_cpu_desc_handle;
-    bd->hFontSrvGpuDescHandle = font_srv_gpu_desc_handle;
-    bd->pFrameResources = new ImGui_ImplDX12_RenderBuffers[num_frames_in_flight];
-    bd->numFramesInFlight = num_frames_in_flight;
-    bd->pd3dSrvDescHeap = cbv_srv_heap;
-    bd->frameIndex = UINT_MAX;
+    // Create a dummy ImGui_ImplDX12_ViewportData holder for the main viewport,
+    // Since this is created and managed by the application, we will only use the ->Resources[] fields.
+    ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+    main_viewport->RendererUserData = IM_NEW(ImGui_ImplDX12_ViewportData)(bd->numFramesInFlight);
 
-    // Create buffers with a default size (they will later be grown as needed)
-    for (int i = 0; i < num_frames_in_flight; i++)
+#ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
+    if (init_info->SrvDescriptorAllocFn == nullptr)
     {
-        ImGui_ImplDX12_RenderBuffers* fr = &bd->pFrameResources[i];
-        fr->IndexBuffer = nullptr;
-        fr->VertexBuffer = nullptr;
-        fr->IndexBufferSize = 10000;
-        fr->VertexBufferSize = 5000;
+        // Wrap legacy behavior of passing space for a single descriptor
+        IM_ASSERT(init_info->LegacySingleSrvCpuDescriptor.ptr != 0 && init_info->LegacySingleSrvGpuDescriptor.ptr != 0);
+        init_info->SrvDescriptorAllocFn = [](ImGui_ImplDX12_InitInfo*, D3D12_CPU_DESCRIPTOR_HANDLE* out_cpu_handle, D3D12_GPU_DESCRIPTOR_HANDLE* out_gpu_handle)
+        {
+            ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
+            IM_ASSERT(bd->LegacySingleDescriptorUsed == false);
+            *out_cpu_handle = bd->InitInfo.LegacySingleSrvCpuDescriptor;
+            *out_gpu_handle = bd->InitInfo.LegacySingleSrvGpuDescriptor;
+            bd->LegacySingleDescriptorUsed = true;
+        };
+        init_info->SrvDescriptorFreeFn = [](ImGui_ImplDX12_InitInfo*, D3D12_CPU_DESCRIPTOR_HANDLE, D3D12_GPU_DESCRIPTOR_HANDLE)
+        {
+            ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
+            IM_ASSERT(bd->LegacySingleDescriptorUsed == true);
+            bd->LegacySingleDescriptorUsed = false;
+        };
     }
+#endif
+
+    // Allocate 1 SRV descriptor for the font texture
+    IM_ASSERT(init_info->SrvDescriptorAllocFn != nullptr && init_info->SrvDescriptorFreeFn != nullptr);
+    init_info->SrvDescriptorAllocFn(&bd->InitInfo, &bd->FontTexture.hFontSrvCpuDescHandle, &bd->FontTexture.hFontSrvGpuDescHandle);
 
     return true;
 }
 
+#ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
+// Legacy initialization API Obsoleted in 1.91.5
+// font_srv_cpu_desc_handle and font_srv_gpu_desc_handle are handles to a single SRV descriptor to use for the internal font texture, they must be in 'srv_descriptor_heap'
+bool ImGui_ImplDX12_Init(ID3D12Device* device, int num_frames_in_flight, DXGI_FORMAT rtv_format, ID3D12DescriptorHeap* srv_descriptor_heap, D3D12_CPU_DESCRIPTOR_HANDLE font_srv_cpu_desc_handle, D3D12_GPU_DESCRIPTOR_HANDLE font_srv_gpu_desc_handle)
+{
+    ImGui_ImplDX12_InitInfo init_info;
+    init_info.Device = device;
+    init_info.NumFramesInFlight = num_frames_in_flight;
+    init_info.RTVFormat = rtv_format;
+    init_info.SrvDescriptorHeap = srv_descriptor_heap;
+    init_info.LegacySingleSrvCpuDescriptor = font_srv_cpu_desc_handle;
+    init_info.LegacySingleSrvGpuDescriptor = font_srv_gpu_desc_handle;;
+    return ImGui_ImplDX12_Init(&init_info);
+}
+#endif
+
 void ImGui_ImplDX12_Shutdown()
 {
     ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
     IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
     ImGuiIO& io = ImGui::GetIO();
 
+    // Manually delete main viewport render resources in-case we haven't initialized for viewports
+    ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+    if (ImGui_ImplDX12_ViewportData* vd = (ImGui_ImplDX12_ViewportData*)main_viewport->RendererUserData)
+    {
+        // We could just call ImGui_ImplDX12_DestroyWindow(main_viewport) as a convenience but that would be misleading since we only use data->Resources[]
+        for (UINT i = 0; i < bd->numFramesInFlight; i++)
+            ImGui_ImplDX12_DestroyRenderBuffers(&vd->FrameRenderBuffers[i]);
+        IM_DELETE(vd);
+        main_viewport->RendererUserData = nullptr;
+    }
+
     // Clean up windows and device objects
+    ImGui_ImplDX12_ShutdownPlatformInterface();
     ImGui_ImplDX12_InvalidateDeviceObjects();
-    delete[] bd->pFrameResources;
+
     io.BackendRendererName = nullptr;
     io.BackendRendererUserData = nullptr;
-    io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset;
+    io.BackendFlags &= ~(ImGuiBackendFlags_RendererHasVtxOffset | ImGuiBackendFlags_RendererHasViewports);
     IM_DELETE(bd);
 }
 
@@ -757,6 +912,246 @@ void ImGui_ImplDX12_NewFrame()
         ImGui_ImplDX12_CreateDeviceObjects();
 }
 
+//--------------------------------------------------------------------------------------------------------
+// MULTI-VIEWPORT / PLATFORM INTERFACE SUPPORT
+// This is an _advanced_ and _optional_ feature, allowing the backend to create and handle multiple viewports simultaneously.
+// If you are new to dear imgui or creating a new binding for dear imgui, it is recommended that you completely ignore this section first..
+//--------------------------------------------------------------------------------------------------------
+
+static void ImGui_ImplDX12_CreateWindow(ImGuiViewport* viewport)
+{
+    ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
+    ImGui_ImplDX12_ViewportData* vd = IM_NEW(ImGui_ImplDX12_ViewportData)(bd->numFramesInFlight);
+    viewport->RendererUserData = vd;
+
+    // PlatformHandleRaw should always be a HWND, whereas PlatformHandle might be a higher-level handle (e.g. GLFWWindow*, SDL_Window*).
+    // Some backends will leave PlatformHandleRaw == 0, in which case we assume PlatformHandle will contain the HWND.
+    HWND hwnd = viewport->PlatformHandleRaw ? (HWND)viewport->PlatformHandleRaw : (HWND)viewport->PlatformHandle;
+    IM_ASSERT(hwnd != 0);
+
+    vd->FrameIndex = UINT_MAX;
+
+    // Create command queue.
+    D3D12_COMMAND_QUEUE_DESC queue_desc = {};
+    queue_desc.Flags = D3D12_COMMAND_QUEUE_FLAG_NONE;
+    queue_desc.Type = D3D12_COMMAND_LIST_TYPE_DIRECT;
+
+    HRESULT res = S_OK;
+    res = bd->pd3dDevice->CreateCommandQueue(&queue_desc, IID_PPV_ARGS(&vd->CommandQueue));
+    IM_ASSERT(res == S_OK);
+
+    // Create command allocator.
+    for (UINT i = 0; i < bd->numFramesInFlight; ++i)
+    {
+        res = bd->pd3dDevice->CreateCommandAllocator(D3D12_COMMAND_LIST_TYPE_DIRECT, IID_PPV_ARGS(&vd->FrameCtx[i].CommandAllocator));
+        IM_ASSERT(res == S_OK);
+    }
+
+    // Create command list.
+    res = bd->pd3dDevice->CreateCommandList(0, D3D12_COMMAND_LIST_TYPE_DIRECT, vd->FrameCtx[0].CommandAllocator, nullptr, IID_PPV_ARGS(&vd->CommandList));
+    IM_ASSERT(res == S_OK);
+    vd->CommandList->Close();
+
+    // Create fence.
+    res = bd->pd3dDevice->CreateFence(0, D3D12_FENCE_FLAG_NONE, IID_PPV_ARGS(&vd->Fence));
+    IM_ASSERT(res == S_OK);
+
+    vd->FenceEvent = CreateEvent(nullptr, FALSE, FALSE, nullptr);
+    IM_ASSERT(vd->FenceEvent != nullptr);
+
+    // Create swap chain
+    // FIXME-VIEWPORT: May want to copy/inherit swap chain settings from the user/application.
+    DXGI_SWAP_CHAIN_DESC1 sd1;
+    ZeroMemory(&sd1, sizeof(sd1));
+    sd1.BufferCount = bd->numFramesInFlight;
+    sd1.Width = (UINT)viewport->Size.x;
+    sd1.Height = (UINT)viewport->Size.y;
+    sd1.Format = bd->RTVFormat;
+    sd1.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
+    sd1.SampleDesc.Count = 1;
+    sd1.SampleDesc.Quality = 0;
+    sd1.SwapEffect = DXGI_SWAP_EFFECT_FLIP_DISCARD;
+    sd1.AlphaMode = DXGI_ALPHA_MODE_UNSPECIFIED;
+    sd1.Scaling = DXGI_SCALING_NONE;
+    sd1.Stereo = FALSE;
+
+    IDXGIFactory4* dxgi_factory = nullptr;
+    res = ::CreateDXGIFactory1(IID_PPV_ARGS(&dxgi_factory));
+    IM_ASSERT(res == S_OK);
+
+    IDXGISwapChain1* swap_chain = nullptr;
+    res = dxgi_factory->CreateSwapChainForHwnd(vd->CommandQueue, hwnd, &sd1, nullptr, nullptr, &swap_chain);
+    IM_ASSERT(res == S_OK);
+
+    dxgi_factory->Release();
+
+    // Or swapChain.As(&mSwapChain)
+    IM_ASSERT(vd->SwapChain == nullptr);
+    swap_chain->QueryInterface(IID_PPV_ARGS(&vd->SwapChain));
+    swap_chain->Release();
+
+    // Create the render targets
+    if (vd->SwapChain)
+    {
+        D3D12_DESCRIPTOR_HEAP_DESC desc = {};
+        desc.Type = D3D12_DESCRIPTOR_HEAP_TYPE_RTV;
+        desc.NumDescriptors = bd->numFramesInFlight;
+        desc.Flags = D3D12_DESCRIPTOR_HEAP_FLAG_NONE;
+        desc.NodeMask = 1;
+
+        HRESULT hr = bd->pd3dDevice->CreateDescriptorHeap(&desc, IID_PPV_ARGS(&vd->RtvDescHeap));
+        IM_ASSERT(hr == S_OK);
+
+        SIZE_T rtv_descriptor_size = bd->pd3dDevice->GetDescriptorHandleIncrementSize(D3D12_DESCRIPTOR_HEAP_TYPE_RTV);
+        D3D12_CPU_DESCRIPTOR_HANDLE rtv_handle = vd->RtvDescHeap->GetCPUDescriptorHandleForHeapStart();
+        for (UINT i = 0; i < bd->numFramesInFlight; i++)
+        {
+            vd->FrameCtx[i].RenderTargetCpuDescriptors = rtv_handle;
+            rtv_handle.ptr += rtv_descriptor_size;
+        }
+
+        ID3D12Resource* back_buffer;
+        for (UINT i = 0; i < bd->numFramesInFlight; i++)
+        {
+            IM_ASSERT(vd->FrameCtx[i].RenderTarget == nullptr);
+            vd->SwapChain->GetBuffer(i, IID_PPV_ARGS(&back_buffer));
+            bd->pd3dDevice->CreateRenderTargetView(back_buffer, nullptr, vd->FrameCtx[i].RenderTargetCpuDescriptors);
+            vd->FrameCtx[i].RenderTarget = back_buffer;
+        }
+    }
+
+    for (UINT i = 0; i < bd->numFramesInFlight; i++)
+        ImGui_ImplDX12_DestroyRenderBuffers(&vd->FrameRenderBuffers[i]);
+}
+
+static void ImGui_WaitForPendingOperations(ImGui_ImplDX12_ViewportData* vd)
+{
+    HRESULT hr = S_FALSE;
+    if (vd && vd->CommandQueue && vd->Fence && vd->FenceEvent)
+    {
+        hr = vd->CommandQueue->Signal(vd->Fence, ++vd->FenceSignaledValue);
+        IM_ASSERT(hr == S_OK);
+        ::WaitForSingleObject(vd->FenceEvent, 0); // Reset any forgotten waits
+        hr = vd->Fence->SetEventOnCompletion(vd->FenceSignaledValue, vd->FenceEvent);
+        IM_ASSERT(hr == S_OK);
+        ::WaitForSingleObject(vd->FenceEvent, INFINITE);
+    }
+}
+
+static void ImGui_ImplDX12_DestroyWindow(ImGuiViewport* viewport)
+{
+    // The main viewport (owned by the application) will always have RendererUserData == 0 since we didn't create the data for it.
+    ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
+    if (ImGui_ImplDX12_ViewportData* vd = (ImGui_ImplDX12_ViewportData*)viewport->RendererUserData)
+    {
+        ImGui_WaitForPendingOperations(vd);
+
+        SafeRelease(vd->CommandQueue);
+        SafeRelease(vd->CommandList);
+        SafeRelease(vd->SwapChain);
+        SafeRelease(vd->RtvDescHeap);
+        SafeRelease(vd->Fence);
+        ::CloseHandle(vd->FenceEvent);
+        vd->FenceEvent = nullptr;
+
+        for (UINT i = 0; i < bd->numFramesInFlight; i++)
+        {
+            SafeRelease(vd->FrameCtx[i].RenderTarget);
+            SafeRelease(vd->FrameCtx[i].CommandAllocator);
+            ImGui_ImplDX12_DestroyRenderBuffers(&vd->FrameRenderBuffers[i]);
+        }
+        IM_DELETE(vd);
+    }
+    viewport->RendererUserData = nullptr;
+}
+
+static void ImGui_ImplDX12_SetWindowSize(ImGuiViewport* viewport, ImVec2 size)
+{
+    ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
+    ImGui_ImplDX12_ViewportData* vd = (ImGui_ImplDX12_ViewportData*)viewport->RendererUserData;
+
+    ImGui_WaitForPendingOperations(vd);
+
+    for (UINT i = 0; i < bd->numFramesInFlight; i++)
+        SafeRelease(vd->FrameCtx[i].RenderTarget);
+
+    if (vd->SwapChain)
+    {
+        ID3D12Resource* back_buffer = nullptr;
+        vd->SwapChain->ResizeBuffers(0, (UINT)size.x, (UINT)size.y, DXGI_FORMAT_UNKNOWN, 0);
+        for (UINT i = 0; i < bd->numFramesInFlight; i++)
+        {
+            vd->SwapChain->GetBuffer(i, IID_PPV_ARGS(&back_buffer));
+            bd->pd3dDevice->CreateRenderTargetView(back_buffer, nullptr, vd->FrameCtx[i].RenderTargetCpuDescriptors);
+            vd->FrameCtx[i].RenderTarget = back_buffer;
+        }
+    }
+}
+
+static void ImGui_ImplDX12_RenderWindow(ImGuiViewport* viewport, void*)
+{
+    ImGui_ImplDX12_Data* bd = ImGui_ImplDX12_GetBackendData();
+    ImGui_ImplDX12_ViewportData* vd = (ImGui_ImplDX12_ViewportData*)viewport->RendererUserData;
+
+    ImGui_ImplDX12_FrameContext* frame_context = &vd->FrameCtx[vd->FrameIndex % bd->numFramesInFlight];
+    UINT back_buffer_idx = vd->SwapChain->GetCurrentBackBufferIndex();
+
+    const ImVec4 clear_color = ImVec4(0.0f, 0.0f, 0.0f, 1.0f);
+    D3D12_RESOURCE_BARRIER barrier = {};
+    barrier.Type = D3D12_RESOURCE_BARRIER_TYPE_TRANSITION;
+    barrier.Flags = D3D12_RESOURCE_BARRIER_FLAG_NONE;
+    barrier.Transition.pResource = vd->FrameCtx[back_buffer_idx].RenderTarget;
+    barrier.Transition.Subresource = D3D12_RESOURCE_BARRIER_ALL_SUBRESOURCES;
+    barrier.Transition.StateBefore = D3D12_RESOURCE_STATE_PRESENT;
+    barrier.Transition.StateAfter = D3D12_RESOURCE_STATE_RENDER_TARGET;
+
+    // Draw
+    ID3D12GraphicsCommandList* cmd_list = vd->CommandList;
+
+    frame_context->CommandAllocator->Reset();
+    cmd_list->Reset(frame_context->CommandAllocator, nullptr);
+    cmd_list->ResourceBarrier(1, &barrier);
+    cmd_list->OMSetRenderTargets(1, &vd->FrameCtx[back_buffer_idx].RenderTargetCpuDescriptors, FALSE, nullptr);
+    if (!(viewport->Flags & ImGuiViewportFlags_NoRendererClear))
+        cmd_list->ClearRenderTargetView(vd->FrameCtx[back_buffer_idx].RenderTargetCpuDescriptors, (float*)&clear_color, 0, nullptr);
+    cmd_list->SetDescriptorHeaps(1, &bd->pd3dSrvDescHeap);
+
+    ImGui_ImplDX12_RenderDrawData(viewport->DrawData, cmd_list);
+
+    barrier.Transition.StateBefore = D3D12_RESOURCE_STATE_RENDER_TARGET;
+    barrier.Transition.StateAfter = D3D12_RESOURCE_STATE_PRESENT;
+    cmd_list->ResourceBarrier(1, &barrier);
+    cmd_list->Close();
+
+    vd->CommandQueue->Wait(vd->Fence, vd->FenceSignaledValue);
+    vd->CommandQueue->ExecuteCommandLists(1, (ID3D12CommandList* const*)&cmd_list);
+    vd->CommandQueue->Signal(vd->Fence, ++vd->FenceSignaledValue);
+}
+
+static void ImGui_ImplDX12_SwapBuffers(ImGuiViewport* viewport, void*)
+{
+    ImGui_ImplDX12_ViewportData* vd = (ImGui_ImplDX12_ViewportData*)viewport->RendererUserData;
+
+    vd->SwapChain->Present(0, 0);
+    while (vd->Fence->GetCompletedValue() < vd->FenceSignaledValue)
+        ::SwitchToThread();
+}
+
+void ImGui_ImplDX12_InitPlatformInterface()
+{
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    platform_io.Renderer_CreateWindow = ImGui_ImplDX12_CreateWindow;
+    platform_io.Renderer_DestroyWindow = ImGui_ImplDX12_DestroyWindow;
+    platform_io.Renderer_SetWindowSize = ImGui_ImplDX12_SetWindowSize;
+    platform_io.Renderer_RenderWindow = ImGui_ImplDX12_RenderWindow;
+    platform_io.Renderer_SwapBuffers = ImGui_ImplDX12_SwapBuffers;
+}
+
+void ImGui_ImplDX12_ShutdownPlatformInterface()
+{
+    ImGui::DestroyPlatformWindows();
+}
+
 //-----------------------------------------------------------------------------
 
 #endif // #ifndef IMGUI_DISABLE

backends/imgui_impl_dx12.h

@@ -3,10 +3,12 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'D3D12_GPU_DESCRIPTOR_HANDLE' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
+//  [X] Renderer: Expose selected render state for draw callbacks to use. Access in '(ImGui_ImplXXXX_RenderState*)GetPlatformIO().Renderer_RenderState'.
+//  [X] Renderer: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
 
-// Important: to compile on 32-bit systems, this backend requires code to be compiled with '#define ImTextureID ImU64'.
-// See imgui_impl_dx12.cpp file for details.
+// The aim of imgui_impl_dx12.h/.cpp is to be usable in your engine without any modification.
+// IF YOU FEEL YOU NEED TO MAKE ANY CHANGE TO THIS CODE, please share them and your feedback at https://github.com/ocornut/imgui/
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -20,25 +22,54 @@
 #include "imgui.h"      // IMGUI_IMPL_API
 #ifndef IMGUI_DISABLE
 #include <dxgiformat.h> // DXGI_FORMAT
+#include <d3d12.h>      // D3D12_CPU_DESCRIPTOR_HANDLE
 
-struct ID3D12Device;
-struct ID3D12DescriptorHeap;
-struct ID3D12GraphicsCommandList;
-struct D3D12_CPU_DESCRIPTOR_HANDLE;
-struct D3D12_GPU_DESCRIPTOR_HANDLE;
+// Initialization data, for ImGui_ImplDX12_Init()
+struct ImGui_ImplDX12_InitInfo
+{
+    ID3D12Device*               Device;
+    ID3D12CommandQueue*         CommandQueue;
+    int                         NumFramesInFlight;
+    DXGI_FORMAT                 RTVFormat;          // RenderTarget format.
+    DXGI_FORMAT                 DSVFormat;          // DepthStencilView format.
+    void*                       UserData;
 
-// cmd_list is the command list that the implementation will use to render imgui draw lists.
-// Before calling the render function, caller must prepare cmd_list by resetting it and setting the appropriate
-// render target and descriptor heap that contains font_srv_cpu_desc_handle/font_srv_gpu_desc_handle.
-// font_srv_cpu_desc_handle and font_srv_gpu_desc_handle are handles to a single SRV descriptor to use for the internal font texture.
-IMGUI_IMPL_API bool     ImGui_ImplDX12_Init(ID3D12Device* device, int num_frames_in_flight, DXGI_FORMAT rtv_format, ID3D12DescriptorHeap* cbv_srv_heap,
-                                            D3D12_CPU_DESCRIPTOR_HANDLE font_srv_cpu_desc_handle, D3D12_GPU_DESCRIPTOR_HANDLE font_srv_gpu_desc_handle);
+    // Allocating SRV descriptors for textures is up to the application, so we provide callbacks.
+    // (current version of the backend will only allocate one descriptor, future versions will need to allocate more)
+    ID3D12DescriptorHeap*       SrvDescriptorHeap;
+    void                        (*SrvDescriptorAllocFn)(ImGui_ImplDX12_InitInfo* info, D3D12_CPU_DESCRIPTOR_HANDLE* out_cpu_desc_handle, D3D12_GPU_DESCRIPTOR_HANDLE* out_gpu_desc_handle);
+    void                        (*SrvDescriptorFreeFn)(ImGui_ImplDX12_InitInfo* info, D3D12_CPU_DESCRIPTOR_HANDLE cpu_desc_handle, D3D12_GPU_DESCRIPTOR_HANDLE gpu_desc_handle);
+#ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
+    D3D12_CPU_DESCRIPTOR_HANDLE LegacySingleSrvCpuDescriptor; // To facilitate transition from single descriptor to allocator callback, you may use those.
+    D3D12_GPU_DESCRIPTOR_HANDLE LegacySingleSrvGpuDescriptor;
+#endif
+
+    ImGui_ImplDX12_InitInfo()   { memset(this, 0, sizeof(*this)); }
+};
+
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
+IMGUI_IMPL_API bool     ImGui_ImplDX12_Init(ImGui_ImplDX12_InitInfo* info);
 IMGUI_IMPL_API void     ImGui_ImplDX12_Shutdown();
 IMGUI_IMPL_API void     ImGui_ImplDX12_NewFrame();
 IMGUI_IMPL_API void     ImGui_ImplDX12_RenderDrawData(ImDrawData* draw_data, ID3D12GraphicsCommandList* graphics_command_list);
 
+#ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
+// Legacy initialization API Obsoleted in 1.91.5
+// font_srv_cpu_desc_handle and font_srv_gpu_desc_handle are handles to a single SRV descriptor to use for the internal font texture, they must be in 'srv_descriptor_heap'
+IMGUI_IMPL_API bool     ImGui_ImplDX12_Init(ID3D12Device* device, int num_frames_in_flight, DXGI_FORMAT rtv_format, ID3D12DescriptorHeap* srv_descriptor_heap, D3D12_CPU_DESCRIPTOR_HANDLE font_srv_cpu_desc_handle, D3D12_GPU_DESCRIPTOR_HANDLE font_srv_gpu_desc_handle);
+#endif
+
 // Use if you want to reset your rendering device without losing Dear ImGui state.
-IMGUI_IMPL_API void     ImGui_ImplDX12_InvalidateDeviceObjects();
 IMGUI_IMPL_API bool     ImGui_ImplDX12_CreateDeviceObjects();
+IMGUI_IMPL_API void     ImGui_ImplDX12_InvalidateDeviceObjects();
+
+// [BETA] Selected render state data shared with callbacks.
+// This is temporarily stored in GetPlatformIO().Renderer_RenderState during the ImGui_ImplDX12_RenderDrawData() call.
+// (Please open an issue if you feel you need access to more data)
+struct ImGui_ImplDX12_RenderState
+{
+    ID3D12Device*               Device;
+    ID3D12GraphicsCommandList*  CommandList;
+};
 
 #endif // #ifndef IMGUI_DISABLE

backends/imgui_impl_dx9.cpp

@@ -3,7 +3,9 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'LPDIRECT3DTEXTURE9' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
+//  [X] Renderer: IMGUI_USE_BGRA_PACKED_COLOR support, as this is the optimal color encoding for DirectX9.
+//  [X] Renderer: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -15,6 +17,8 @@
 
 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
+//  2024-XX-XX: Platform: Added support for multiple windows via the ImGuiPlatformIO interface.
+//  2024-10-07: DirectX9: Changed default texture sampler to Clamp instead of Repeat/Wrap.
 //  2024-02-12: DirectX9: Using RGBA format when supported by the driver to avoid CPU side conversion. (#6575)
 //  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
 //  2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
@@ -51,6 +55,7 @@ struct ImGui_ImplDX9_Data
     LPDIRECT3DTEXTURE9          FontTexture;
     int                         VertexBufferSize;
     int                         IndexBufferSize;
+    bool                        HasRgbaSupport;
 
     ImGui_ImplDX9_Data()        { memset((void*)this, 0, sizeof(*this)); VertexBufferSize = 5000; IndexBufferSize = 10000; }
 };
@@ -76,6 +81,12 @@ static ImGui_ImplDX9_Data* ImGui_ImplDX9_GetBackendData()
     return ImGui::GetCurrentContext() ? (ImGui_ImplDX9_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
 }
 
+// Forward Declarations
+static void ImGui_ImplDX9_InitMultiViewportSupport();
+static void ImGui_ImplDX9_ShutdownMultiViewportSupport();
+static void ImGui_ImplDX9_CreateDeviceObjectsForPlatformWindows();
+static void ImGui_ImplDX9_InvalidateDeviceObjectsForPlatformWindows();
+
 // Functions
 static void ImGui_ImplDX9_SetupRenderState(ImDrawData* draw_data)
 {
@@ -88,41 +99,45 @@ static void ImGui_ImplDX9_SetupRenderState(ImDrawData* draw_data)
     vp.Height = (DWORD)draw_data->DisplaySize.y;
     vp.MinZ = 0.0f;
     vp.MaxZ = 1.0f;
-    bd->pd3dDevice->SetViewport(&vp);
+
+    LPDIRECT3DDEVICE9 device = bd->pd3dDevice;
+    device->SetViewport(&vp);
 
     // Setup render state: fixed-pipeline, alpha-blending, no face culling, no depth testing, shade mode (for gradient), bilinear sampling.
-    bd->pd3dDevice->SetPixelShader(nullptr);
-    bd->pd3dDevice->SetVertexShader(nullptr);
-    bd->pd3dDevice->SetRenderState(D3DRS_FILLMODE, D3DFILL_SOLID);
-    bd->pd3dDevice->SetRenderState(D3DRS_SHADEMODE, D3DSHADE_GOURAUD);
-    bd->pd3dDevice->SetRenderState(D3DRS_ZWRITEENABLE, FALSE);
-    bd->pd3dDevice->SetRenderState(D3DRS_ALPHATESTENABLE, FALSE);
-    bd->pd3dDevice->SetRenderState(D3DRS_CULLMODE, D3DCULL_NONE);
-    bd->pd3dDevice->SetRenderState(D3DRS_ZENABLE, FALSE);
-    bd->pd3dDevice->SetRenderState(D3DRS_ALPHABLENDENABLE, TRUE);
-    bd->pd3dDevice->SetRenderState(D3DRS_BLENDOP, D3DBLENDOP_ADD);
-    bd->pd3dDevice->SetRenderState(D3DRS_SRCBLEND, D3DBLEND_SRCALPHA);
-    bd->pd3dDevice->SetRenderState(D3DRS_DESTBLEND, D3DBLEND_INVSRCALPHA);
-    bd->pd3dDevice->SetRenderState(D3DRS_SEPARATEALPHABLENDENABLE, TRUE);
-    bd->pd3dDevice->SetRenderState(D3DRS_SRCBLENDALPHA, D3DBLEND_ONE);
-    bd->pd3dDevice->SetRenderState(D3DRS_DESTBLENDALPHA, D3DBLEND_INVSRCALPHA);
-    bd->pd3dDevice->SetRenderState(D3DRS_SCISSORTESTENABLE, TRUE);
-    bd->pd3dDevice->SetRenderState(D3DRS_FOGENABLE, FALSE);
-    bd->pd3dDevice->SetRenderState(D3DRS_RANGEFOGENABLE, FALSE);
-    bd->pd3dDevice->SetRenderState(D3DRS_SPECULARENABLE, FALSE);
-    bd->pd3dDevice->SetRenderState(D3DRS_STENCILENABLE, FALSE);
-    bd->pd3dDevice->SetRenderState(D3DRS_CLIPPING, TRUE);
-    bd->pd3dDevice->SetRenderState(D3DRS_LIGHTING, FALSE);
-    bd->pd3dDevice->SetTextureStageState(0, D3DTSS_COLOROP, D3DTOP_MODULATE);
-    bd->pd3dDevice->SetTextureStageState(0, D3DTSS_COLORARG1, D3DTA_TEXTURE);
-    bd->pd3dDevice->SetTextureStageState(0, D3DTSS_COLORARG2, D3DTA_DIFFUSE);
-    bd->pd3dDevice->SetTextureStageState(0, D3DTSS_ALPHAOP, D3DTOP_MODULATE);
-    bd->pd3dDevice->SetTextureStageState(0, D3DTSS_ALPHAARG1, D3DTA_TEXTURE);
-    bd->pd3dDevice->SetTextureStageState(0, D3DTSS_ALPHAARG2, D3DTA_DIFFUSE);
-    bd->pd3dDevice->SetTextureStageState(1, D3DTSS_COLOROP, D3DTOP_DISABLE);
-    bd->pd3dDevice->SetTextureStageState(1, D3DTSS_ALPHAOP, D3DTOP_DISABLE);
-    bd->pd3dDevice->SetSamplerState(0, D3DSAMP_MINFILTER, D3DTEXF_LINEAR);
-    bd->pd3dDevice->SetSamplerState(0, D3DSAMP_MAGFILTER, D3DTEXF_LINEAR);
+    device->SetPixelShader(nullptr);
+    device->SetVertexShader(nullptr);
+    device->SetRenderState(D3DRS_FILLMODE, D3DFILL_SOLID);
+    device->SetRenderState(D3DRS_SHADEMODE, D3DSHADE_GOURAUD);
+    device->SetRenderState(D3DRS_ZWRITEENABLE, FALSE);
+    device->SetRenderState(D3DRS_ALPHATESTENABLE, FALSE);
+    device->SetRenderState(D3DRS_CULLMODE, D3DCULL_NONE);
+    device->SetRenderState(D3DRS_ZENABLE, FALSE);
+    device->SetRenderState(D3DRS_ALPHABLENDENABLE, TRUE);
+    device->SetRenderState(D3DRS_BLENDOP, D3DBLENDOP_ADD);
+    device->SetRenderState(D3DRS_SRCBLEND, D3DBLEND_SRCALPHA);
+    device->SetRenderState(D3DRS_DESTBLEND, D3DBLEND_INVSRCALPHA);
+    device->SetRenderState(D3DRS_SEPARATEALPHABLENDENABLE, TRUE);
+    device->SetRenderState(D3DRS_SRCBLENDALPHA, D3DBLEND_ONE);
+    device->SetRenderState(D3DRS_DESTBLENDALPHA, D3DBLEND_INVSRCALPHA);
+    device->SetRenderState(D3DRS_SCISSORTESTENABLE, TRUE);
+    device->SetRenderState(D3DRS_FOGENABLE, FALSE);
+    device->SetRenderState(D3DRS_RANGEFOGENABLE, FALSE);
+    device->SetRenderState(D3DRS_SPECULARENABLE, FALSE);
+    device->SetRenderState(D3DRS_STENCILENABLE, FALSE);
+    device->SetRenderState(D3DRS_CLIPPING, TRUE);
+    device->SetRenderState(D3DRS_LIGHTING, FALSE);
+    device->SetTextureStageState(0, D3DTSS_COLOROP, D3DTOP_MODULATE);
+    device->SetTextureStageState(0, D3DTSS_COLORARG1, D3DTA_TEXTURE);
+    device->SetTextureStageState(0, D3DTSS_COLORARG2, D3DTA_DIFFUSE);
+    device->SetTextureStageState(0, D3DTSS_ALPHAOP, D3DTOP_MODULATE);
+    device->SetTextureStageState(0, D3DTSS_ALPHAARG1, D3DTA_TEXTURE);
+    device->SetTextureStageState(0, D3DTSS_ALPHAARG2, D3DTA_DIFFUSE);
+    device->SetTextureStageState(1, D3DTSS_COLOROP, D3DTOP_DISABLE);
+    device->SetTextureStageState(1, D3DTSS_ALPHAOP, D3DTOP_DISABLE);
+    device->SetSamplerState(0, D3DSAMP_MINFILTER, D3DTEXF_LINEAR);
+    device->SetSamplerState(0, D3DSAMP_MAGFILTER, D3DTEXF_LINEAR);
+    device->SetSamplerState(0, D3DSAMP_ADDRESSU, D3DTADDRESS_CLAMP);
+    device->SetSamplerState(0, D3DSAMP_ADDRESSV, D3DTADDRESS_CLAMP);
 
     // Setup orthographic projection matrix
     // Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right). DisplayPos is (0,0) for single viewport apps.
@@ -140,9 +155,9 @@ static void ImGui_ImplDX9_SetupRenderState(ImDrawData* draw_data)
             0.0f,         0.0f,         0.5f,  0.0f,
             (L+R)/(L-R),  (T+B)/(B-T),  0.5f,  1.0f
         } } };
-        bd->pd3dDevice->SetTransform(D3DTS_WORLD, &mat_identity);
-        bd->pd3dDevice->SetTransform(D3DTS_VIEW, &mat_identity);
-        bd->pd3dDevice->SetTransform(D3DTS_PROJECTION, &mat_projection);
+        device->SetTransform(D3DTS_WORLD, &mat_identity);
+        device->SetTransform(D3DTS_VIEW, &mat_identity);
+        device->SetTransform(D3DTS_PROJECTION, &mat_projection);
     }
 }
 
@@ -153,51 +168,53 @@ void ImGui_ImplDX9_RenderDrawData(ImDrawData* draw_data)
     if (draw_data->DisplaySize.x <= 0.0f || draw_data->DisplaySize.y <= 0.0f)
         return;
 
-    // Create and grow buffers if needed
     ImGui_ImplDX9_Data* bd = ImGui_ImplDX9_GetBackendData();
+    LPDIRECT3DDEVICE9 device = bd->pd3dDevice;
+
+    // Create and grow buffers if needed
     if (!bd->pVB || bd->VertexBufferSize < draw_data->TotalVtxCount)
     {
         if (bd->pVB) { bd->pVB->Release(); bd->pVB = nullptr; }
         bd->VertexBufferSize = draw_data->TotalVtxCount + 5000;
-        if (bd->pd3dDevice->CreateVertexBuffer(bd->VertexBufferSize * sizeof(CUSTOMVERTEX), D3DUSAGE_DYNAMIC | D3DUSAGE_WRITEONLY, D3DFVF_CUSTOMVERTEX, D3DPOOL_DEFAULT, &bd->pVB, nullptr) < 0)
+        if (device->CreateVertexBuffer(bd->VertexBufferSize * sizeof(CUSTOMVERTEX), D3DUSAGE_DYNAMIC | D3DUSAGE_WRITEONLY, D3DFVF_CUSTOMVERTEX, D3DPOOL_DEFAULT, &bd->pVB, nullptr) < 0)
             return;
     }
     if (!bd->pIB || bd->IndexBufferSize < draw_data->TotalIdxCount)
     {
         if (bd->pIB) { bd->pIB->Release(); bd->pIB = nullptr; }
         bd->IndexBufferSize = draw_data->TotalIdxCount + 10000;
-        if (bd->pd3dDevice->CreateIndexBuffer(bd->IndexBufferSize * sizeof(ImDrawIdx), D3DUSAGE_DYNAMIC | D3DUSAGE_WRITEONLY, sizeof(ImDrawIdx) == 2 ? D3DFMT_INDEX16 : D3DFMT_INDEX32, D3DPOOL_DEFAULT, &bd->pIB, nullptr) < 0)
+        if (device->CreateIndexBuffer(bd->IndexBufferSize * sizeof(ImDrawIdx), D3DUSAGE_DYNAMIC | D3DUSAGE_WRITEONLY, sizeof(ImDrawIdx) == 2 ? D3DFMT_INDEX16 : D3DFMT_INDEX32, D3DPOOL_DEFAULT, &bd->pIB, nullptr) < 0)
             return;
     }
 
     // Backup the DX9 state
-    IDirect3DStateBlock9* d3d9_state_block = nullptr;
-    if (bd->pd3dDevice->CreateStateBlock(D3DSBT_ALL, &d3d9_state_block) < 0)
+    IDirect3DStateBlock9* state_block = nullptr;
+    if (device->CreateStateBlock(D3DSBT_ALL, &state_block) < 0)
         return;
-    if (d3d9_state_block->Capture() < 0)
+    if (state_block->Capture() < 0)
     {
-        d3d9_state_block->Release();
+        state_block->Release();
         return;
     }
 
     // Backup the DX9 transform (DX9 documentation suggests that it is included in the StateBlock but it doesn't appear to)
     D3DMATRIX last_world, last_view, last_projection;
-    bd->pd3dDevice->GetTransform(D3DTS_WORLD, &last_world);
-    bd->pd3dDevice->GetTransform(D3DTS_VIEW, &last_view);
-    bd->pd3dDevice->GetTransform(D3DTS_PROJECTION, &last_projection);
+    device->GetTransform(D3DTS_WORLD, &last_world);
+    device->GetTransform(D3DTS_VIEW, &last_view);
+    device->GetTransform(D3DTS_PROJECTION, &last_projection);
 
     // Allocate buffers
     CUSTOMVERTEX* vtx_dst;
     ImDrawIdx* idx_dst;
     if (bd->pVB->Lock(0, (UINT)(draw_data->TotalVtxCount * sizeof(CUSTOMVERTEX)), (void**)&vtx_dst, D3DLOCK_DISCARD) < 0)
     {
-        d3d9_state_block->Release();
+        state_block->Release();
         return;
     }
     if (bd->pIB->Lock(0, (UINT)(draw_data->TotalIdxCount * sizeof(ImDrawIdx)), (void**)&idx_dst, D3DLOCK_DISCARD) < 0)
     {
         bd->pVB->Unlock();
-        d3d9_state_block->Release();
+        state_block->Release();
         return;
     }
 
@@ -207,9 +224,9 @@ void ImGui_ImplDX9_RenderDrawData(ImDrawData* draw_data)
     //  2) to avoid repacking vertices: #define IMGUI_OVERRIDE_DRAWVERT_STRUCT_LAYOUT struct ImDrawVert { ImVec2 pos; float z; ImU32 col; ImVec2 uv; }
     for (int n = 0; n < draw_data->CmdListsCount; n++)
     {
-        const ImDrawList* cmd_list = draw_data->CmdLists[n];
-        const ImDrawVert* vtx_src = cmd_list->VtxBuffer.Data;
-        for (int i = 0; i < cmd_list->VtxBuffer.Size; i++)
+        const ImDrawList* draw_list = draw_data->CmdLists[n];
+        const ImDrawVert* vtx_src = draw_list->VtxBuffer.Data;
+        for (int i = 0; i < draw_list->VtxBuffer.Size; i++)
         {
             vtx_dst->pos[0] = vtx_src->pos.x;
             vtx_dst->pos[1] = vtx_src->pos.y;
@@ -220,14 +237,14 @@ void ImGui_ImplDX9_RenderDrawData(ImDrawData* draw_data)
             vtx_dst++;
             vtx_src++;
         }
-        memcpy(idx_dst, cmd_list->IdxBuffer.Data, cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx));
-        idx_dst += cmd_list->IdxBuffer.Size;
+        memcpy(idx_dst, draw_list->IdxBuffer.Data, draw_list->IdxBuffer.Size * sizeof(ImDrawIdx));
+        idx_dst += draw_list->IdxBuffer.Size;
     }
     bd->pVB->Unlock();
     bd->pIB->Unlock();
-    bd->pd3dDevice->SetStreamSource(0, bd->pVB, 0, sizeof(CUSTOMVERTEX));
-    bd->pd3dDevice->SetIndices(bd->pIB);
-    bd->pd3dDevice->SetFVF(D3DFVF_CUSTOMVERTEX);
+    device->SetStreamSource(0, bd->pVB, 0, sizeof(CUSTOMVERTEX));
+    device->SetIndices(bd->pIB);
+    device->SetFVF(D3DFVF_CUSTOMVERTEX);
 
     // Setup desired DX state
     ImGui_ImplDX9_SetupRenderState(draw_data);
@@ -239,10 +256,10 @@ void ImGui_ImplDX9_RenderDrawData(ImDrawData* draw_data)
     ImVec2 clip_off = draw_data->DisplayPos;
     for (int n = 0; n < draw_data->CmdListsCount; n++)
     {
-        const ImDrawList* cmd_list = draw_data->CmdLists[n];
-        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        const ImDrawList* draw_list = draw_data->CmdLists[n];
+        for (int cmd_i = 0; cmd_i < draw_list->CmdBuffer.Size; cmd_i++)
         {
-            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            const ImDrawCmd* pcmd = &draw_list->CmdBuffer[cmd_i];
             if (pcmd->UserCallback != nullptr)
             {
                 // User callback, registered via ImDrawList::AddCallback()
@@ -250,7 +267,7 @@ void ImGui_ImplDX9_RenderDrawData(ImDrawData* draw_data)
                 if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
                     ImGui_ImplDX9_SetupRenderState(draw_data);
                 else
-                    pcmd->UserCallback(cmd_list, pcmd);
+                    pcmd->UserCallback(draw_list, pcmd);
             }
             else
             {
@@ -260,63 +277,38 @@ void ImGui_ImplDX9_RenderDrawData(ImDrawData* draw_data)
                 if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
                     continue;
 
-                // Apply Scissor/clipping rectangle, Bind texture, Draw
+                // Apply scissor/clipping rectangle
                 const RECT r = { (LONG)clip_min.x, (LONG)clip_min.y, (LONG)clip_max.x, (LONG)clip_max.y };
+                device->SetScissorRect(&r);
+
+                // Bind texture, Draw
                 const LPDIRECT3DTEXTURE9 texture = (LPDIRECT3DTEXTURE9)pcmd->GetTexID();
-                bd->pd3dDevice->SetTexture(0, texture);
-                bd->pd3dDevice->SetScissorRect(&r);
-                bd->pd3dDevice->DrawIndexedPrimitive(D3DPT_TRIANGLELIST, pcmd->VtxOffset + global_vtx_offset, 0, (UINT)cmd_list->VtxBuffer.Size, pcmd->IdxOffset + global_idx_offset, pcmd->ElemCount / 3);
+                device->SetTexture(0, texture);
+                device->DrawIndexedPrimitive(D3DPT_TRIANGLELIST, pcmd->VtxOffset + global_vtx_offset, 0, (UINT)draw_list->VtxBuffer.Size, pcmd->IdxOffset + global_idx_offset, pcmd->ElemCount / 3);
             }
         }
-        global_idx_offset += cmd_list->IdxBuffer.Size;
-        global_vtx_offset += cmd_list->VtxBuffer.Size;
+        global_idx_offset += draw_list->IdxBuffer.Size;
+        global_vtx_offset += draw_list->VtxBuffer.Size;
     }
 
+    // When using multi-viewports, it appears that there's an odd logic in DirectX9 which prevent subsequent windows
+    // from rendering until the first window submits at least one draw call, even once. That's our workaround. (see #2560)
+    if (global_vtx_offset == 0)
+        bd->pd3dDevice->DrawIndexedPrimitive(D3DPT_TRIANGLELIST, 0, 0, 0, 0, 0);
+
     // Restore the DX9 transform
-    bd->pd3dDevice->SetTransform(D3DTS_WORLD, &last_world);
-    bd->pd3dDevice->SetTransform(D3DTS_VIEW, &last_view);
-    bd->pd3dDevice->SetTransform(D3DTS_PROJECTION, &last_projection);
+    device->SetTransform(D3DTS_WORLD, &last_world);
+    device->SetTransform(D3DTS_VIEW, &last_view);
+    device->SetTransform(D3DTS_PROJECTION, &last_projection);
 
     // Restore the DX9 state
-    d3d9_state_block->Apply();
-    d3d9_state_block->Release();
+    state_block->Apply();
+    state_block->Release();
 }
 
-bool ImGui_ImplDX9_Init(IDirect3DDevice9* device)
+static bool ImGui_ImplDX9_CheckFormatSupport(LPDIRECT3DDEVICE9 pDevice, D3DFORMAT format)
 {
-    ImGuiIO& io = ImGui::GetIO();
-    IMGUI_CHECKVERSION();
-    IM_ASSERT(io.BackendRendererUserData == nullptr && "Already initialized a renderer backend!");
-
-    // Setup backend capabilities flags
-    ImGui_ImplDX9_Data* bd = IM_NEW(ImGui_ImplDX9_Data)();
-    io.BackendRendererUserData = (void*)bd;
-    io.BackendRendererName = "imgui_impl_dx9";
-    io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset;  // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
-
-    bd->pd3dDevice = device;
-    bd->pd3dDevice->AddRef();
-
-    return true;
-}
-
-void ImGui_ImplDX9_Shutdown()
-{
-    ImGui_ImplDX9_Data* bd = ImGui_ImplDX9_GetBackendData();
-    IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
-    ImGuiIO& io = ImGui::GetIO();
-
-    ImGui_ImplDX9_InvalidateDeviceObjects();
-    if (bd->pd3dDevice) { bd->pd3dDevice->Release(); }
-    io.BackendRendererName = nullptr;
-    io.BackendRendererUserData = nullptr;
-    io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset;
-    IM_DELETE(bd);
-}
-
-static bool ImGui_ImplDX9_CheckFormatSupport(IDirect3DDevice9* pDevice, D3DFORMAT format)
-{
-    IDirect3D9* pd3d = nullptr;
+    LPDIRECT3D9 pd3d = nullptr;
     if (pDevice->GetDirect3D(&pd3d) != D3D_OK)
         return false;
     D3DDEVICE_CREATION_PARAMETERS param = {};
@@ -332,6 +324,65 @@ static bool ImGui_ImplDX9_CheckFormatSupport(IDirect3DDevice9* pDevice, D3DFORMA
     return support;
 }
 
+bool ImGui_ImplDX9_Init(IDirect3DDevice9* device)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    IMGUI_CHECKVERSION();
+    IM_ASSERT(io.BackendRendererUserData == nullptr && "Already initialized a renderer backend!");
+
+    // Setup backend capabilities flags
+    ImGui_ImplDX9_Data* bd = IM_NEW(ImGui_ImplDX9_Data)();
+    io.BackendRendererUserData = (void*)bd;
+    io.BackendRendererName = "imgui_impl_dx9";
+    io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset;  // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
+    io.BackendFlags |= ImGuiBackendFlags_RendererHasViewports;  // We can create multi-viewports on the Renderer side (optional)
+
+    bd->pd3dDevice = device;
+    bd->pd3dDevice->AddRef();
+    bd->HasRgbaSupport = ImGui_ImplDX9_CheckFormatSupport(bd->pd3dDevice, D3DFMT_A8B8G8R8);
+
+    ImGui_ImplDX9_InitMultiViewportSupport();
+
+    return true;
+}
+
+void ImGui_ImplDX9_Shutdown()
+{
+    ImGui_ImplDX9_Data* bd = ImGui_ImplDX9_GetBackendData();
+    IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    ImGui_ImplDX9_ShutdownMultiViewportSupport();
+    ImGui_ImplDX9_InvalidateDeviceObjects();
+    if (bd->pd3dDevice) { bd->pd3dDevice->Release(); }
+    io.BackendRendererName = nullptr;
+    io.BackendRendererUserData = nullptr;
+    io.BackendFlags &= ~(ImGuiBackendFlags_RendererHasVtxOffset | ImGuiBackendFlags_RendererHasViewports);
+    IM_DELETE(bd);
+}
+
+// Convert RGBA32 to BGRA32 (because RGBA32 is not well supported by DX9 devices)
+static void ImGui_ImplDX9_CopyTextureRegion(bool tex_use_colors, ImU32* src, int src_pitch, ImU32* dst, int dst_pitch, int w, int h)
+{
+#ifndef IMGUI_USE_BGRA_PACKED_COLOR
+    ImGui_ImplDX9_Data* bd = ImGui_ImplDX9_GetBackendData();
+    const bool convert_rgba_to_bgra = (!bd->HasRgbaSupport && tex_use_colors);
+#else
+    const bool convert_rgba_to_bgra = false;
+    IM_UNUSED(tex_use_colors);
+#endif
+    for (int y = 0; y < h; y++)
+    {
+        ImU32* src_p = (ImU32*)((unsigned char*)src + src_pitch * y);
+        ImU32* dst_p = (ImU32*)((unsigned char*)dst + dst_pitch * y);
+        if (convert_rgba_to_bgra)
+            for (int x = w; x > 0; x--, src_p++, dst_p++) // Convert copy
+                *dst_p = IMGUI_COL_TO_DX9_ARGB(*src_p);
+        else
+            memcpy(dst_p, src_p, w * 4); // Raw copy
+    }
+}
+
 static bool ImGui_ImplDX9_CreateFontsTexture()
 {
     // Build texture atlas
@@ -341,39 +392,18 @@ static bool ImGui_ImplDX9_CreateFontsTexture()
     int width, height, bytes_per_pixel;
     io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height, &bytes_per_pixel);
 
-    // Convert RGBA32 to BGRA32 (because RGBA32 is not well supported by DX9 devices)
-#ifndef IMGUI_USE_BGRA_PACKED_COLOR
-    const bool rgba_support = ImGui_ImplDX9_CheckFormatSupport(bd->pd3dDevice, D3DFMT_A8B8G8R8);
-    if (!rgba_support && io.Fonts->TexPixelsUseColors)
-    {
-        ImU32* dst_start = (ImU32*)ImGui::MemAlloc((size_t)width * height * bytes_per_pixel);
-        for (ImU32* src = (ImU32*)pixels, *dst = dst_start, *dst_end = dst_start + (size_t)width * height; dst < dst_end; src++, dst++)
-            *dst = IMGUI_COL_TO_DX9_ARGB(*src);
-        pixels = (unsigned char*)dst_start;
-    }
-#else
-    const bool rgba_support = false;
-#endif
-
     // Upload texture to graphics system
     bd->FontTexture = nullptr;
-    if (bd->pd3dDevice->CreateTexture(width, height, 1, D3DUSAGE_DYNAMIC, rgba_support ? D3DFMT_A8B8G8R8 : D3DFMT_A8R8G8B8, D3DPOOL_DEFAULT, &bd->FontTexture, nullptr) < 0)
+    if (bd->pd3dDevice->CreateTexture(width, height, 1, D3DUSAGE_DYNAMIC, bd->HasRgbaSupport ? D3DFMT_A8B8G8R8 : D3DFMT_A8R8G8B8, D3DPOOL_DEFAULT, &bd->FontTexture, nullptr) < 0)
         return false;
     D3DLOCKED_RECT tex_locked_rect;
     if (bd->FontTexture->LockRect(0, &tex_locked_rect, nullptr, 0) != D3D_OK)
         return false;
-    for (int y = 0; y < height; y++)
-        memcpy((unsigned char*)tex_locked_rect.pBits + (size_t)tex_locked_rect.Pitch * y, pixels + (size_t)width * bytes_per_pixel * y, (size_t)width * bytes_per_pixel);
+    ImGui_ImplDX9_CopyTextureRegion(io.Fonts->TexPixelsUseColors, (ImU32*)pixels, width * bytes_per_pixel, (ImU32*)tex_locked_rect.pBits, (int)tex_locked_rect.Pitch, width, height);
     bd->FontTexture->UnlockRect(0);
 
     // Store our identifier
     io.Fonts->SetTexID((ImTextureID)bd->FontTexture);
-
-#ifndef IMGUI_USE_BGRA_PACKED_COLOR
-    if (!rgba_support && io.Fonts->TexPixelsUseColors)
-        ImGui::MemFree(pixels);
-#endif
-
     return true;
 }
 
@@ -384,6 +414,7 @@ bool ImGui_ImplDX9_CreateDeviceObjects()
         return false;
     if (!ImGui_ImplDX9_CreateFontsTexture())
         return false;
+    ImGui_ImplDX9_CreateDeviceObjectsForPlatformWindows();
     return true;
 }
 
@@ -395,6 +426,7 @@ void ImGui_ImplDX9_InvalidateDeviceObjects()
     if (bd->pVB) { bd->pVB->Release(); bd->pVB = nullptr; }
     if (bd->pIB) { bd->pIB->Release(); bd->pIB = nullptr; }
     if (bd->FontTexture) { bd->FontTexture->Release(); bd->FontTexture = nullptr; ImGui::GetIO().Fonts->SetTexID(0); } // We copied bd->pFontTextureView to io.Fonts->TexID so let's clear that as well.
+    ImGui_ImplDX9_InvalidateDeviceObjectsForPlatformWindows();
 }
 
 void ImGui_ImplDX9_NewFrame()
@@ -406,6 +438,148 @@ void ImGui_ImplDX9_NewFrame()
         ImGui_ImplDX9_CreateDeviceObjects();
 }
 
+//--------------------------------------------------------------------------------------------------------
+// MULTI-VIEWPORT / PLATFORM INTERFACE SUPPORT
+// This is an _advanced_ and _optional_ feature, allowing the backend to create and handle multiple viewports simultaneously.
+// If you are new to dear imgui or creating a new binding for dear imgui, it is recommended that you completely ignore this section first..
+//--------------------------------------------------------------------------------------------------------
+
+// Helper structure we store in the void* RendererUserData field of each ImGuiViewport to easily retrieve our backend data.
+struct ImGui_ImplDX9_ViewportData
+{
+    IDirect3DSwapChain9*    SwapChain;
+    D3DPRESENT_PARAMETERS   d3dpp;
+
+    ImGui_ImplDX9_ViewportData()  { SwapChain = nullptr; ZeroMemory(&d3dpp, sizeof(D3DPRESENT_PARAMETERS)); }
+    ~ImGui_ImplDX9_ViewportData() { IM_ASSERT(SwapChain == nullptr); }
+};
+
+static void ImGui_ImplDX9_CreateWindow(ImGuiViewport* viewport)
+{
+    ImGui_ImplDX9_Data* bd = ImGui_ImplDX9_GetBackendData();
+    ImGui_ImplDX9_ViewportData* vd = IM_NEW(ImGui_ImplDX9_ViewportData)();
+    viewport->RendererUserData = vd;
+
+    // PlatformHandleRaw should always be a HWND, whereas PlatformHandle might be a higher-level handle (e.g. GLFWWindow*, SDL_Window*).
+    // Some backends will leave PlatformHandleRaw == 0, in which case we assume PlatformHandle will contain the HWND.
+    HWND hwnd = viewport->PlatformHandleRaw ? (HWND)viewport->PlatformHandleRaw : (HWND)viewport->PlatformHandle;
+    IM_ASSERT(hwnd != 0);
+
+    ZeroMemory(&vd->d3dpp, sizeof(D3DPRESENT_PARAMETERS));
+    vd->d3dpp.Windowed = TRUE;
+    vd->d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;
+    vd->d3dpp.BackBufferWidth = (UINT)viewport->Size.x;
+    vd->d3dpp.BackBufferHeight = (UINT)viewport->Size.y;
+    vd->d3dpp.BackBufferFormat = D3DFMT_UNKNOWN;
+    vd->d3dpp.hDeviceWindow = hwnd;
+    vd->d3dpp.EnableAutoDepthStencil = FALSE;
+    vd->d3dpp.AutoDepthStencilFormat = D3DFMT_D16;
+    vd->d3dpp.PresentationInterval = D3DPRESENT_INTERVAL_IMMEDIATE;   // Present without vsync
+
+    HRESULT hr = bd->pd3dDevice->CreateAdditionalSwapChain(&vd->d3dpp, &vd->SwapChain); IM_UNUSED(hr);
+    IM_ASSERT(hr == D3D_OK);
+    IM_ASSERT(vd->SwapChain != nullptr);
+}
+
+static void ImGui_ImplDX9_DestroyWindow(ImGuiViewport* viewport)
+{
+    // The main viewport (owned by the application) will always have RendererUserData == 0 since we didn't create the data for it.
+    if (ImGui_ImplDX9_ViewportData* vd = (ImGui_ImplDX9_ViewportData*)viewport->RendererUserData)
+    {
+        if (vd->SwapChain)
+            vd->SwapChain->Release();
+        vd->SwapChain = nullptr;
+        ZeroMemory(&vd->d3dpp, sizeof(D3DPRESENT_PARAMETERS));
+        IM_DELETE(vd);
+    }
+    viewport->RendererUserData = nullptr;
+}
+
+static void ImGui_ImplDX9_SetWindowSize(ImGuiViewport* viewport, ImVec2 size)
+{
+    ImGui_ImplDX9_Data* bd = ImGui_ImplDX9_GetBackendData();
+    ImGui_ImplDX9_ViewportData* vd = (ImGui_ImplDX9_ViewportData*)viewport->RendererUserData;
+    if (vd->SwapChain)
+    {
+        vd->SwapChain->Release();
+        vd->SwapChain = nullptr;
+        vd->d3dpp.BackBufferWidth = (UINT)size.x;
+        vd->d3dpp.BackBufferHeight = (UINT)size.y;
+        HRESULT hr = bd->pd3dDevice->CreateAdditionalSwapChain(&vd->d3dpp, &vd->SwapChain); IM_UNUSED(hr);
+        IM_ASSERT(hr == D3D_OK);
+    }
+}
+
+static void ImGui_ImplDX9_RenderWindow(ImGuiViewport* viewport, void*)
+{
+    ImGui_ImplDX9_Data* bd = ImGui_ImplDX9_GetBackendData();
+    ImGui_ImplDX9_ViewportData* vd = (ImGui_ImplDX9_ViewportData*)viewport->RendererUserData;
+    ImVec4 clear_color = ImVec4(0.0f, 0.0f, 0.0f, 1.0f);
+
+    LPDIRECT3DSURFACE9 render_target = nullptr;
+    LPDIRECT3DSURFACE9 last_render_target = nullptr;
+    LPDIRECT3DSURFACE9 last_depth_stencil = nullptr;
+    vd->SwapChain->GetBackBuffer(0, D3DBACKBUFFER_TYPE_MONO, &render_target);
+    bd->pd3dDevice->GetRenderTarget(0, &last_render_target);
+    bd->pd3dDevice->GetDepthStencilSurface(&last_depth_stencil);
+    bd->pd3dDevice->SetRenderTarget(0, render_target);
+    bd->pd3dDevice->SetDepthStencilSurface(nullptr);
+
+    if (!(viewport->Flags & ImGuiViewportFlags_NoRendererClear))
+    {
+        D3DCOLOR clear_col_dx = D3DCOLOR_RGBA((int)(clear_color.x*255.0f), (int)(clear_color.y*255.0f), (int)(clear_color.z*255.0f), (int)(clear_color.w*255.0f));
+        bd->pd3dDevice->Clear(0, nullptr, D3DCLEAR_TARGET, clear_col_dx, 1.0f, 0);
+    }
+
+    ImGui_ImplDX9_RenderDrawData(viewport->DrawData);
+
+    // Restore render target
+    bd->pd3dDevice->SetRenderTarget(0, last_render_target);
+    bd->pd3dDevice->SetDepthStencilSurface(last_depth_stencil);
+    render_target->Release();
+    last_render_target->Release();
+    if (last_depth_stencil) last_depth_stencil->Release();
+}
+
+static void ImGui_ImplDX9_SwapBuffers(ImGuiViewport* viewport, void*)
+{
+    ImGui_ImplDX9_ViewportData* vd = (ImGui_ImplDX9_ViewportData*)viewport->RendererUserData;
+    HRESULT hr = vd->SwapChain->Present(nullptr, nullptr, vd->d3dpp.hDeviceWindow, nullptr, 0);
+    // Let main application handle D3DERR_DEVICELOST by resetting the device.
+    IM_ASSERT(SUCCEEDED(hr) || hr == D3DERR_DEVICELOST);
+}
+
+static void ImGui_ImplDX9_InitMultiViewportSupport()
+{
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    platform_io.Renderer_CreateWindow = ImGui_ImplDX9_CreateWindow;
+    platform_io.Renderer_DestroyWindow = ImGui_ImplDX9_DestroyWindow;
+    platform_io.Renderer_SetWindowSize = ImGui_ImplDX9_SetWindowSize;
+    platform_io.Renderer_RenderWindow = ImGui_ImplDX9_RenderWindow;
+    platform_io.Renderer_SwapBuffers = ImGui_ImplDX9_SwapBuffers;
+}
+
+static void ImGui_ImplDX9_ShutdownMultiViewportSupport()
+{
+    ImGui::DestroyPlatformWindows();
+}
+
+static void ImGui_ImplDX9_CreateDeviceObjectsForPlatformWindows()
+{
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    for (int i = 1; i < platform_io.Viewports.Size; i++)
+        if (!platform_io.Viewports[i]->RendererUserData)
+            ImGui_ImplDX9_CreateWindow(platform_io.Viewports[i]);
+}
+
+static void ImGui_ImplDX9_InvalidateDeviceObjectsForPlatformWindows()
+{
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    for (int i = 1; i < platform_io.Viewports.Size; i++)
+        if (platform_io.Viewports[i]->RendererUserData)
+            ImGui_ImplDX9_DestroyWindow(platform_io.Viewports[i]);
+}
+
 //-----------------------------------------------------------------------------
 
 #endif // #ifndef IMGUI_DISABLE

backends/imgui_impl_dx9.h

@@ -3,7 +3,9 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'LPDIRECT3DTEXTURE9' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
+//  [X] Renderer: IMGUI_USE_BGRA_PACKED_COLOR support, as this is the optimal color encoding for DirectX9.
+//  [X] Renderer: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -19,6 +21,7 @@
 
 struct IDirect3DDevice9;
 
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
 IMGUI_IMPL_API bool     ImGui_ImplDX9_Init(IDirect3DDevice9* device);
 IMGUI_IMPL_API void     ImGui_ImplDX9_Shutdown();
 IMGUI_IMPL_API void     ImGui_ImplDX9_NewFrame();

backends/imgui_impl_glfw.h

@@ -1,13 +1,17 @@
 // dear imgui: Platform Backend for GLFW
 // This needs to be used along with a Renderer (e.g. OpenGL3, Vulkan, WebGPU..)
 // (Info: GLFW is a cross-platform general purpose library for handling windows, inputs, OpenGL/Vulkan graphics context creation, etc.)
+// (Requires: GLFW 3.1+. Prefer GLFW 3.3+ for full feature support.)
 
 // Implemented features:
 //  [X] Platform: Clipboard support.
 //  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen/Pen (Windows only).
-//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy GLFW_KEY_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy GLFW_KEY_* values are obsolete since 1.87 and not supported since 1.91.5]
 //  [X] Platform: Gamepad support. Enable with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
-//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange' (note: the resizing cursors requires GLFW 3.4+).
+//  [X] Platform: Mouse cursor shape and visibility (ImGuiBackendFlags_HasMouseCursors). Resizing cursors requires GLFW 3.4+! Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+//  [X] Platform: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
+// Missing features or Issues:
+//  [ ] Platform: Multi-viewport: ParentViewportID not honored, and so io.ConfigViewportsNoDefaultParent has no effect (minor).
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -24,15 +28,17 @@
 struct GLFWwindow;
 struct GLFWmonitor;
 
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
 IMGUI_IMPL_API bool     ImGui_ImplGlfw_InitForOpenGL(GLFWwindow* window, bool install_callbacks);
 IMGUI_IMPL_API bool     ImGui_ImplGlfw_InitForVulkan(GLFWwindow* window, bool install_callbacks);
 IMGUI_IMPL_API bool     ImGui_ImplGlfw_InitForOther(GLFWwindow* window, bool install_callbacks);
 IMGUI_IMPL_API void     ImGui_ImplGlfw_Shutdown();
 IMGUI_IMPL_API void     ImGui_ImplGlfw_NewFrame();
 
-// Emscripten related initialization phase methods
+// Emscripten related initialization phase methods (call after ImGui_ImplGlfw_InitForOpenGL)
 #ifdef __EMSCRIPTEN__
-IMGUI_IMPL_API void     ImGui_ImplGlfw_InstallEmscriptenCanvasResizeCallback(const char* canvas_selector);
+IMGUI_IMPL_API void     ImGui_ImplGlfw_InstallEmscriptenCallbacks(GLFWwindow* window, const char* canvas_selector);
+//static inline void    ImGui_ImplGlfw_InstallEmscriptenCanvasResizeCallback(const char* canvas_selector) { ImGui_ImplGlfw_InstallEmscriptenCallbacks(nullptr, canvas_selector); } } // Renamed in 1.91.0
 #endif
 
 // GLFW callbacks install
@@ -55,4 +61,7 @@ IMGUI_IMPL_API void     ImGui_ImplGlfw_KeyCallback(GLFWwindow* window, int key,
 IMGUI_IMPL_API void     ImGui_ImplGlfw_CharCallback(GLFWwindow* window, unsigned int c);
 IMGUI_IMPL_API void     ImGui_ImplGlfw_MonitorCallback(GLFWmonitor* monitor, int event);
 
+// GLFW helpers
+IMGUI_IMPL_API void     ImGui_ImplGlfw_Sleep(int milliseconds);
+
 #endif // #ifndef IMGUI_DISABLE

backends/imgui_impl_glut.cpp

@@ -6,13 +6,14 @@
 // !!! Nowadays, prefer using GLFW or SDL instead!
 
 // Implemented features:
-//  [X] Platform: Partial keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy GLUT values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
-// Issues:
+//  [X] Platform: Partial keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy GLUT values are obsolete since 1.87 and not supported since 1.91.5]
+// Missing features or Issues:
 //  [ ] Platform: GLUT is unable to distinguish e.g. Backspace from CTRL+H or TAB from CTRL+I
 //  [ ] Platform: Missing horizontal mouse wheel support.
 //  [ ] Platform: Missing mouse cursor shape/visibility support.
 //  [ ] Platform: Missing clipboard support (not supported by Glut).
 //  [ ] Platform: Missing gamepad support.
+//  [ ] Platform: Missing multi-viewport support (multiple windows).
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.

backends/imgui_impl_glut.h

@@ -6,13 +6,14 @@
 // !!! Nowadays, prefer using GLFW or SDL instead!
 
 // Implemented features:
-//  [X] Platform: Partial keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy GLUT values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
-// Issues:
+//  [X] Platform: Partial keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy GLUT values are obsolete since 1.87 and not supported since 1.91.5]
+// Missing features or Issues:
 //  [ ] Platform: GLUT is unable to distinguish e.g. Backspace from CTRL+H or TAB from CTRL+I
 //  [ ] Platform: Missing horizontal mouse wheel support.
 //  [ ] Platform: Missing mouse cursor shape/visibility support.
 //  [ ] Platform: Missing clipboard support (not supported by Glut).
 //  [ ] Platform: Missing gamepad support.
+//  [ ] Platform: Missing multi-viewport support (multiple windows).
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -26,6 +27,7 @@
 #ifndef IMGUI_DISABLE
 #include "imgui.h"      // IMGUI_IMPL_API
 
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
 IMGUI_IMPL_API bool     ImGui_ImplGLUT_Init();
 IMGUI_IMPL_API void     ImGui_ImplGLUT_InstallFuncs();
 IMGUI_IMPL_API void     ImGui_ImplGLUT_Shutdown();

backends/imgui_impl_metal.h

@@ -3,7 +3,8 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'MTLTexture' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
+//  [X] Renderer: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -25,6 +26,7 @@
 @class MTLRenderPassDescriptor;
 @protocol MTLDevice, MTLCommandBuffer, MTLRenderCommandEncoder;
 
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
 IMGUI_IMPL_API bool ImGui_ImplMetal_Init(id<MTLDevice> device);
 IMGUI_IMPL_API void ImGui_ImplMetal_Shutdown();
 IMGUI_IMPL_API void ImGui_ImplMetal_NewFrame(MTLRenderPassDescriptor* renderPassDescriptor);
@@ -51,6 +53,7 @@ IMGUI_IMPL_API void ImGui_ImplMetal_DestroyDeviceObjects();
 #include <Metal/Metal.hpp>
 #ifndef __OBJC__
 
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
 IMGUI_IMPL_API bool ImGui_ImplMetal_Init(MTL::Device* device);
 IMGUI_IMPL_API void ImGui_ImplMetal_Shutdown();
 IMGUI_IMPL_API void ImGui_ImplMetal_NewFrame(MTL::RenderPassDescriptor* renderPassDescriptor);

backends/imgui_impl_metal.mm

@@ -3,7 +3,8 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'MTLTexture' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
+//  [X] Renderer: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -15,6 +16,7 @@
 
 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
+//  2024-XX-XX: Metal: Added support for multiple windows via the ImGuiPlatformIO interface.
 //  2022-08-23: Metal: Update deprecated property 'sampleCount'->'rasterSampleCount'.
 //  2022-07-05: Metal: Add dispatch synchronization.
 //  2022-06-30: Metal: Use __bridge for ARC based systems.
@@ -38,6 +40,12 @@
 #import <time.h>
 #import <Metal/Metal.h>
 
+// Forward Declarations
+static void ImGui_ImplMetal_InitMultiViewportSupport();
+static void ImGui_ImplMetal_ShutdownMultiViewportSupport();
+static void ImGui_ImplMetal_CreateDeviceObjectsForPlatformWindows();
+static void ImGui_ImplMetal_InvalidateDeviceObjectsForPlatformWindows();
+
 #pragma mark - Support classes
 
 // A wrapper around a MTLBuffer object that knows the last time it was reused
@@ -76,7 +84,7 @@ struct ImGui_ImplMetal_Data
 {
     MetalContext*               SharedMetalContext;
 
-    ImGui_ImplMetal_Data()      { memset(this, 0, sizeof(*this)); }
+    ImGui_ImplMetal_Data()      { memset((void*)this, 0, sizeof(*this)); }
 };
 
 static ImGui_ImplMetal_Data*    ImGui_ImplMetal_GetBackendData()    { return ImGui::GetCurrentContext() ? (ImGui_ImplMetal_Data*)ImGui::GetIO().BackendRendererUserData : nullptr; }
@@ -132,10 +140,13 @@ bool ImGui_ImplMetal_Init(id<MTLDevice> device)
     io.BackendRendererUserData = (void*)bd;
     io.BackendRendererName = "imgui_impl_metal";
     io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset;  // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
+    io.BackendFlags |= ImGuiBackendFlags_RendererHasViewports;  // We can create multi-viewports on the Renderer side (optional)
 
     bd->SharedMetalContext = [[MetalContext alloc] init];
     bd->SharedMetalContext.device = device;
 
+    ImGui_ImplMetal_InitMultiViewportSupport();
+
     return true;
 }
 
@@ -143,13 +154,14 @@ void ImGui_ImplMetal_Shutdown()
 {
     ImGui_ImplMetal_Data* bd = ImGui_ImplMetal_GetBackendData();
     IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
+    ImGui_ImplMetal_ShutdownMultiViewportSupport();
     ImGui_ImplMetal_DestroyDeviceObjects();
     ImGui_ImplMetal_DestroyBackendData();
 
     ImGuiIO& io = ImGui::GetIO();
     io.BackendRendererName = nullptr;
     io.BackendRendererUserData = nullptr;
-    io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset;
+    io.BackendFlags &= ~(ImGuiBackendFlags_RendererHasVtxOffset | ImGuiBackendFlags_RendererHasViewports);
 }
 
 void ImGui_ImplMetal_NewFrame(MTLRenderPassDescriptor* renderPassDescriptor)
@@ -246,14 +258,14 @@ void ImGui_ImplMetal_RenderDrawData(ImDrawData* drawData, id<MTLCommandBuffer> c
     size_t indexBufferOffset = 0;
     for (int n = 0; n < drawData->CmdListsCount; n++)
     {
-        const ImDrawList* cmd_list = drawData->CmdLists[n];
+        const ImDrawList* draw_list = drawData->CmdLists[n];
 
-        memcpy((char*)vertexBuffer.buffer.contents + vertexBufferOffset, cmd_list->VtxBuffer.Data, (size_t)cmd_list->VtxBuffer.Size * sizeof(ImDrawVert));
-        memcpy((char*)indexBuffer.buffer.contents + indexBufferOffset, cmd_list->IdxBuffer.Data, (size_t)cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx));
+        memcpy((char*)vertexBuffer.buffer.contents + vertexBufferOffset, draw_list->VtxBuffer.Data, (size_t)draw_list->VtxBuffer.Size * sizeof(ImDrawVert));
+        memcpy((char*)indexBuffer.buffer.contents + indexBufferOffset, draw_list->IdxBuffer.Data, (size_t)draw_list->IdxBuffer.Size * sizeof(ImDrawIdx));
 
-        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        for (int cmd_i = 0; cmd_i < draw_list->CmdBuffer.Size; cmd_i++)
         {
-            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            const ImDrawCmd* pcmd = &draw_list->CmdBuffer[cmd_i];
             if (pcmd->UserCallback)
             {
                 // User callback, registered via ImDrawList::AddCallback()
@@ -261,7 +273,7 @@ void ImGui_ImplMetal_RenderDrawData(ImDrawData* drawData, id<MTLCommandBuffer> c
                 if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
                     ImGui_ImplMetal_SetupRenderState(drawData, commandBuffer, commandEncoder, renderPipelineState, vertexBuffer, vertexBufferOffset);
                 else
-                    pcmd->UserCallback(cmd_list, pcmd);
+                    pcmd->UserCallback(draw_list, pcmd);
             }
             else
             {
@@ -291,7 +303,7 @@ void ImGui_ImplMetal_RenderDrawData(ImDrawData* drawData, id<MTLCommandBuffer> c
 
                 // Bind texture, Draw
                 if (ImTextureID tex_id = pcmd->GetTexID())
-                    [commandEncoder setFragmentTexture:(__bridge id<MTLTexture>)(tex_id) atIndex:0];
+                    [commandEncoder setFragmentTexture:(__bridge id<MTLTexture>)(void*)(intptr_t)(tex_id) atIndex:0];
 
                 [commandEncoder setVertexBufferOffset:(vertexBufferOffset + pcmd->VtxOffset * sizeof(ImDrawVert)) atIndex:0];
                 [commandEncoder drawIndexedPrimitives:MTLPrimitiveTypeTriangle
@@ -302,8 +314,8 @@ void ImGui_ImplMetal_RenderDrawData(ImDrawData* drawData, id<MTLCommandBuffer> c
             }
         }
 
-        vertexBufferOffset += (size_t)cmd_list->VtxBuffer.Size * sizeof(ImDrawVert);
-        indexBufferOffset += (size_t)cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx);
+        vertexBufferOffset += (size_t)draw_list->VtxBuffer.Size * sizeof(ImDrawVert);
+        indexBufferOffset += (size_t)draw_list->IdxBuffer.Size * sizeof(ImDrawIdx);
     }
 
     [commandBuffer addCompletedHandler:^(id<MTLCommandBuffer>)
@@ -347,7 +359,7 @@ bool ImGui_ImplMetal_CreateFontsTexture(id<MTLDevice> device)
     id <MTLTexture> texture = [device newTextureWithDescriptor:textureDescriptor];
     [texture replaceRegion:MTLRegionMake2D(0, 0, (NSUInteger)width, (NSUInteger)height) mipmapLevel:0 withBytes:pixels bytesPerRow:(NSUInteger)width * 4];
     bd->SharedMetalContext.fontTexture = texture;
-    io.Fonts->SetTexID((__bridge void*)bd->SharedMetalContext.fontTexture); // ImTextureID == void*
+    io.Fonts->SetTexID((ImTextureID)(intptr_t)(__bridge void*)bd->SharedMetalContext.fontTexture); // ImTextureID == ImU64
 
     return (bd->SharedMetalContext.fontTexture != nil);
 }
@@ -367,6 +379,7 @@ bool ImGui_ImplMetal_CreateDeviceObjects(id<MTLDevice> device)
     depthStencilDescriptor.depthWriteEnabled = NO;
     depthStencilDescriptor.depthCompareFunction = MTLCompareFunctionAlways;
     bd->SharedMetalContext.depthStencilState = [device newDepthStencilStateWithDescriptor:depthStencilDescriptor];
+    ImGui_ImplMetal_CreateDeviceObjectsForPlatformWindows();
     ImGui_ImplMetal_CreateFontsTexture(device);
 
     return true;
@@ -376,9 +389,155 @@ void ImGui_ImplMetal_DestroyDeviceObjects()
 {
     ImGui_ImplMetal_Data* bd = ImGui_ImplMetal_GetBackendData();
     ImGui_ImplMetal_DestroyFontsTexture();
+    ImGui_ImplMetal_InvalidateDeviceObjectsForPlatformWindows();
     [bd->SharedMetalContext.renderPipelineStateCache removeAllObjects];
 }
 
+#pragma mark - Multi-viewport support
+
+#import <QuartzCore/CAMetalLayer.h>
+
+#if TARGET_OS_OSX
+#import <Cocoa/Cocoa.h>
+#endif
+
+//--------------------------------------------------------------------------------------------------------
+// MULTI-VIEWPORT / PLATFORM INTERFACE SUPPORT
+// This is an _advanced_ and _optional_ feature, allowing the back-end to create and handle multiple viewports simultaneously.
+// If you are new to dear imgui or creating a new binding for dear imgui, it is recommended that you completely ignore this section first..
+//--------------------------------------------------------------------------------------------------------
+
+struct ImGuiViewportDataMetal
+{
+    CAMetalLayer*               MetalLayer;
+    id<MTLCommandQueue>         CommandQueue;
+    MTLRenderPassDescriptor*    RenderPassDescriptor;
+    void*                       Handle = nullptr;
+    bool                        FirstFrame = true;
+};
+
+static void ImGui_ImplMetal_CreateWindow(ImGuiViewport* viewport)
+{
+    ImGui_ImplMetal_Data* bd = ImGui_ImplMetal_GetBackendData();
+    ImGuiViewportDataMetal* data = IM_NEW(ImGuiViewportDataMetal)();
+    viewport->RendererUserData = data;
+
+    // PlatformHandleRaw should always be a NSWindow*, whereas PlatformHandle might be a higher-level handle (e.g. GLFWWindow*, SDL_Window*).
+    // Some back-ends will leave PlatformHandleRaw == 0, in which case we assume PlatformHandle will contain the NSWindow*.
+    void* handle = viewport->PlatformHandleRaw ? viewport->PlatformHandleRaw : viewport->PlatformHandle;
+    IM_ASSERT(handle != nullptr);
+
+    id<MTLDevice> device = bd->SharedMetalContext.device;
+    CAMetalLayer* layer = [CAMetalLayer layer];
+    layer.device = device;
+    layer.framebufferOnly = YES;
+    layer.pixelFormat = bd->SharedMetalContext.framebufferDescriptor.colorPixelFormat;
+#if TARGET_OS_OSX
+    NSWindow* window = (__bridge NSWindow*)handle;
+    NSView* view = window.contentView;
+    view.layer = layer;
+    view.wantsLayer = YES;
+#endif
+    data->MetalLayer = layer;
+    data->CommandQueue = [device newCommandQueue];
+    data->RenderPassDescriptor = [[MTLRenderPassDescriptor alloc] init];
+    data->Handle = handle;
+}
+
+static void ImGui_ImplMetal_DestroyWindow(ImGuiViewport* viewport)
+{
+    // The main viewport (owned by the application) will always have RendererUserData == 0 since we didn't create the data for it.
+    if (ImGuiViewportDataMetal* data = (ImGuiViewportDataMetal*)viewport->RendererUserData)
+        IM_DELETE(data);
+    viewport->RendererUserData = nullptr;
+}
+
+inline static CGSize MakeScaledSize(CGSize size, CGFloat scale)
+{
+    return CGSizeMake(size.width * scale, size.height * scale);
+}
+
+static void ImGui_ImplMetal_SetWindowSize(ImGuiViewport* viewport, ImVec2 size)
+{
+    ImGuiViewportDataMetal* data = (ImGuiViewportDataMetal*)viewport->RendererUserData;
+    data->MetalLayer.drawableSize = MakeScaledSize(CGSizeMake(size.x, size.y), viewport->DpiScale);
+}
+
+static void ImGui_ImplMetal_RenderWindow(ImGuiViewport* viewport, void*)
+{
+    ImGuiViewportDataMetal* data = (ImGuiViewportDataMetal*)viewport->RendererUserData;
+
+#if TARGET_OS_OSX
+    void* handle = viewport->PlatformHandleRaw ? viewport->PlatformHandleRaw : viewport->PlatformHandle;
+    NSWindow* window = (__bridge NSWindow*)handle;
+
+    // Always render the first frame, regardless of occlusionState, to avoid an initial flicker
+    if ((window.occlusionState & NSWindowOcclusionStateVisible) == 0 && !data->FirstFrame)
+    {
+        // Do not render windows which are completely occluded. Calling -[CAMetalLayer nextDrawable] will hang for
+        // approximately 1 second if the Metal layer is completely occluded.
+        return;
+    }
+    data->FirstFrame = false;
+
+    viewport->DpiScale = (float)window.backingScaleFactor;
+    if (data->MetalLayer.contentsScale != viewport->DpiScale)
+    {
+        data->MetalLayer.contentsScale = viewport->DpiScale;
+        data->MetalLayer.drawableSize = MakeScaledSize(window.frame.size, viewport->DpiScale);
+    }
+    viewport->DrawData->FramebufferScale = ImVec2(viewport->DpiScale, viewport->DpiScale);
+#endif
+
+    id <CAMetalDrawable> drawable = [data->MetalLayer nextDrawable];
+    if (drawable == nil)
+        return;
+
+    MTLRenderPassDescriptor* renderPassDescriptor = data->RenderPassDescriptor;
+    renderPassDescriptor.colorAttachments[0].texture = drawable.texture;
+    renderPassDescriptor.colorAttachments[0].clearColor = MTLClearColorMake(0, 0, 0, 0);
+    if ((viewport->Flags & ImGuiViewportFlags_NoRendererClear) == 0)
+        renderPassDescriptor.colorAttachments[0].loadAction = MTLLoadActionClear;
+
+    id <MTLCommandBuffer> commandBuffer = [data->CommandQueue commandBuffer];
+    id <MTLRenderCommandEncoder> renderEncoder = [commandBuffer renderCommandEncoderWithDescriptor:renderPassDescriptor];
+    ImGui_ImplMetal_RenderDrawData(viewport->DrawData, commandBuffer, renderEncoder);
+    [renderEncoder endEncoding];
+
+    [commandBuffer presentDrawable:drawable];
+    [commandBuffer commit];
+}
+
+static void ImGui_ImplMetal_InitMultiViewportSupport()
+{
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    platform_io.Renderer_CreateWindow = ImGui_ImplMetal_CreateWindow;
+    platform_io.Renderer_DestroyWindow = ImGui_ImplMetal_DestroyWindow;
+    platform_io.Renderer_SetWindowSize = ImGui_ImplMetal_SetWindowSize;
+    platform_io.Renderer_RenderWindow = ImGui_ImplMetal_RenderWindow;
+}
+
+static void ImGui_ImplMetal_ShutdownMultiViewportSupport()
+{
+    ImGui::DestroyPlatformWindows();
+}
+
+static void ImGui_ImplMetal_CreateDeviceObjectsForPlatformWindows()
+{
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    for (int i = 1; i < platform_io.Viewports.Size; i++)
+        if (!platform_io.Viewports[i]->RendererUserData)
+            ImGui_ImplMetal_CreateWindow(platform_io.Viewports[i]);
+}
+
+static void ImGui_ImplMetal_InvalidateDeviceObjectsForPlatformWindows()
+{
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    for (int i = 1; i < platform_io.Viewports.Size; i++)
+        if (platform_io.Viewports[i]->RendererUserData)
+            ImGui_ImplMetal_DestroyWindow(platform_io.Viewports[i]);
+}
+
 #pragma mark - MetalBuffer implementation
 
 @implementation MetalBuffer

backends/imgui_impl_opengl2.cpp

@@ -3,6 +3,9 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'GLuint' OpenGL texture identifier as void*/ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
+// Missing features or Issues:
+//  [ ] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -22,6 +25,9 @@
 
 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
+//  2024-XX-XX: Platform: Added support for multiple windows via the ImGuiPlatformIO interface.
+//  2024-10-07: OpenGL: Changed default texture sampler to Clamp instead of Repeat/Wrap.
+//  2024-06-28: OpenGL: ImGui_ImplOpenGL2_NewFrame() recreates font texture if it has been destroyed by ImGui_ImplOpenGL2_DestroyFontsTexture(). (#7748)
 //  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
 //  2021-12-08: OpenGL: Fixed mishandling of the ImDrawCmd::IdxOffset field! This is an old bug but it never had an effect until some internal rendering changes in 1.86.
 //  2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
@@ -79,6 +85,10 @@ static ImGui_ImplOpenGL2_Data* ImGui_ImplOpenGL2_GetBackendData()
     return ImGui::GetCurrentContext() ? (ImGui_ImplOpenGL2_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
 }
 
+// Forward Declarations
+static void ImGui_ImplOpenGL2_InitMultiViewportSupport();
+static void ImGui_ImplOpenGL2_ShutdownMultiViewportSupport();
+
 // Functions
 bool    ImGui_ImplOpenGL2_Init()
 {
@@ -90,6 +100,9 @@ bool    ImGui_ImplOpenGL2_Init()
     ImGui_ImplOpenGL2_Data* bd = IM_NEW(ImGui_ImplOpenGL2_Data)();
     io.BackendRendererUserData = (void*)bd;
     io.BackendRendererName = "imgui_impl_opengl2";
+    io.BackendFlags |= ImGuiBackendFlags_RendererHasViewports;    // We can create multi-viewports on the Renderer side (optional)
+
+    ImGui_ImplOpenGL2_InitMultiViewportSupport();
 
     return true;
 }
@@ -100,9 +113,11 @@ void    ImGui_ImplOpenGL2_Shutdown()
     IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
     ImGuiIO& io = ImGui::GetIO();
 
+    ImGui_ImplOpenGL2_ShutdownMultiViewportSupport();
     ImGui_ImplOpenGL2_DestroyDeviceObjects();
     io.BackendRendererName = nullptr;
     io.BackendRendererUserData = nullptr;
+    io.BackendFlags &= ~ImGuiBackendFlags_RendererHasViewports;
     IM_DELETE(bd);
 }
 
@@ -113,6 +128,8 @@ void    ImGui_ImplOpenGL2_NewFrame()
 
     if (!bd->FontTexture)
         ImGui_ImplOpenGL2_CreateDeviceObjects();
+    if (!bd->FontTexture)
+        ImGui_ImplOpenGL2_CreateFontsTexture();
 }
 
 static void ImGui_ImplOpenGL2_SetupRenderState(ImDrawData* draw_data, int fb_width, int fb_height)
@@ -189,16 +206,16 @@ void ImGui_ImplOpenGL2_RenderDrawData(ImDrawData* draw_data)
     // Render command lists
     for (int n = 0; n < draw_data->CmdListsCount; n++)
     {
-        const ImDrawList* cmd_list = draw_data->CmdLists[n];
-        const ImDrawVert* vtx_buffer = cmd_list->VtxBuffer.Data;
-        const ImDrawIdx* idx_buffer = cmd_list->IdxBuffer.Data;
+        const ImDrawList* draw_list = draw_data->CmdLists[n];
+        const ImDrawVert* vtx_buffer = draw_list->VtxBuffer.Data;
+        const ImDrawIdx* idx_buffer = draw_list->IdxBuffer.Data;
         glVertexPointer(2, GL_FLOAT, sizeof(ImDrawVert), (const GLvoid*)((const char*)vtx_buffer + offsetof(ImDrawVert, pos)));
         glTexCoordPointer(2, GL_FLOAT, sizeof(ImDrawVert), (const GLvoid*)((const char*)vtx_buffer + offsetof(ImDrawVert, uv)));
         glColorPointer(4, GL_UNSIGNED_BYTE, sizeof(ImDrawVert), (const GLvoid*)((const char*)vtx_buffer + offsetof(ImDrawVert, col)));
 
-        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        for (int cmd_i = 0; cmd_i < draw_list->CmdBuffer.Size; cmd_i++)
         {
-            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            const ImDrawCmd* pcmd = &draw_list->CmdBuffer[cmd_i];
             if (pcmd->UserCallback)
             {
                 // User callback, registered via ImDrawList::AddCallback()
@@ -206,7 +223,7 @@ void ImGui_ImplOpenGL2_RenderDrawData(ImDrawData* draw_data)
                 if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
                     ImGui_ImplOpenGL2_SetupRenderState(draw_data, fb_width, fb_height);
                 else
-                    pcmd->UserCallback(cmd_list, pcmd);
+                    pcmd->UserCallback(draw_list, pcmd);
             }
             else
             {
@@ -260,6 +277,8 @@ bool ImGui_ImplOpenGL2_CreateFontsTexture()
     glBindTexture(GL_TEXTURE_2D, bd->FontTexture);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
     glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
     glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixels);
 
@@ -294,6 +313,35 @@ void    ImGui_ImplOpenGL2_DestroyDeviceObjects()
     ImGui_ImplOpenGL2_DestroyFontsTexture();
 }
 
+
+//--------------------------------------------------------------------------------------------------------
+// MULTI-VIEWPORT / PLATFORM INTERFACE SUPPORT
+// This is an _advanced_ and _optional_ feature, allowing the backend to create and handle multiple viewports simultaneously.
+// If you are new to dear imgui or creating a new binding for dear imgui, it is recommended that you completely ignore this section first..
+//--------------------------------------------------------------------------------------------------------
+
+static void ImGui_ImplOpenGL2_RenderWindow(ImGuiViewport* viewport, void*)
+{
+    if (!(viewport->Flags & ImGuiViewportFlags_NoRendererClear))
+    {
+        ImVec4 clear_color = ImVec4(0.0f, 0.0f, 0.0f, 1.0f);
+        glClearColor(clear_color.x, clear_color.y, clear_color.z, clear_color.w);
+        glClear(GL_COLOR_BUFFER_BIT);
+    }
+    ImGui_ImplOpenGL2_RenderDrawData(viewport->DrawData);
+}
+
+static void ImGui_ImplOpenGL2_InitMultiViewportSupport()
+{
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    platform_io.Renderer_RenderWindow = ImGui_ImplOpenGL2_RenderWindow;
+}
+
+static void ImGui_ImplOpenGL2_ShutdownMultiViewportSupport()
+{
+    ImGui::DestroyPlatformWindows();
+}
+
 //-----------------------------------------------------------------------------
 
 #if defined(__clang__)

backends/imgui_impl_opengl2.h

@@ -3,6 +3,9 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'GLuint' OpenGL texture identifier as void*/ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
+// Missing features or Issues:
+//  [ ] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -24,6 +27,7 @@
 #include "imgui.h"      // IMGUI_IMPL_API
 #ifndef IMGUI_DISABLE
 
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
 IMGUI_IMPL_API bool     ImGui_ImplOpenGL2_Init();
 IMGUI_IMPL_API void     ImGui_ImplOpenGL2_Shutdown();
 IMGUI_IMPL_API void     ImGui_ImplOpenGL2_NewFrame();

backends/imgui_impl_opengl3.cpp

@@ -5,7 +5,8 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'GLuint' OpenGL texture identifier as void*/ImTextureID. Read the FAQ about ImTextureID!
-//  [x] Renderer: Large meshes support (64k+ vertices) with 16-bit indices (Desktop OpenGL only).
+//  [x] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset) [Desktop OpenGL only!]
+//  [X] Renderer: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
 
 // About WebGL/ES:
 // - You need to '#define IMGUI_IMPL_OPENGL_ES2' or '#define IMGUI_IMPL_OPENGL_ES3' to use WebGL or OpenGL ES.
@@ -22,6 +23,9 @@
 
 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
+//  2024-XX-XX: Platform: Added support for multiple windows via the ImGuiPlatformIO interface.
+//  2024-10-07: OpenGL: Changed default texture sampler to Clamp instead of Repeat/Wrap.
+//  2024-06-28: OpenGL: ImGui_ImplOpenGL3_NewFrame() recreates font texture if it has been destroyed by ImGui_ImplOpenGL3_DestroyFontsTexture(). (#7748)
 //  2024-05-07: OpenGL: Update loader for Linux to support EGL/GLVND. (#7562)
 //  2024-04-16: OpenGL: Detect ES3 contexts on desktop based on version string, to e.g. avoid calling glPolygonMode() on them. (#7447)
 //  2024-01-09: OpenGL: Update GL3W based imgui_impl_opengl3_loader.h to load "libGL.so" and variants, fixing regression on distros missing a symlink.
@@ -123,6 +127,7 @@
 // Clang/GCC warnings with -Weverything
 #if defined(__clang__)
 #pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunknown-warning-option" // warning: ignore unknown flags
 #pragma clang diagnostic ignored "-Wold-style-cast"         // warning: use of old-style cast
 #pragma clang diagnostic ignored "-Wsign-conversion"        // warning: implicit conversion changes signedness
 #pragma clang diagnostic ignored "-Wunused-macros"          // warning: macro is not used
@@ -161,6 +166,7 @@
 // In the rest of your app/engine, you can use another loader of your choice (gl3w, glew, glad, glbinding, glext, glLoadGen, etc.).
 // If you happen to be developing a new feature for this backend (imgui_impl_opengl3.cpp):
 // - You may need to regenerate imgui_impl_opengl3_loader.h to add new symbols. See https://github.com/dearimgui/gl3w_stripped
+//   Typically you would run: python3 ./gl3w_gen.py --output ../imgui/backends/imgui_impl_opengl3_loader.h --ref ../imgui/backends/imgui_impl_opengl3.cpp ./extra_symbols.txt
 // - You can temporarily use an unstripped version. See https://github.com/dearimgui/gl3w_stripped/releases
 // Changes to this backend using new APIs should be accompanied by a regenerated stripped loader version.
 #define IMGL3W_IMPL
@@ -247,6 +253,10 @@ static ImGui_ImplOpenGL3_Data* ImGui_ImplOpenGL3_GetBackendData()
     return ImGui::GetCurrentContext() ? (ImGui_ImplOpenGL3_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
 }
 
+// Forward Declarations
+static void ImGui_ImplOpenGL3_InitMultiViewportSupport();
+static void ImGui_ImplOpenGL3_ShutdownMultiViewportSupport();
+
 // OpenGL vertex attribute state (for ES 1.0 and ES 2.0 only)
 #ifndef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY
 struct ImGui_ImplOpenGL3_VtxAttribState
@@ -293,13 +303,13 @@ bool    ImGui_ImplOpenGL3_Init(const char* glsl_version)
     io.BackendRendererName = "imgui_impl_opengl3";
 
     // Query for GL version (e.g. 320 for GL 3.2)
+    const char* gl_version_str = (const char*)glGetString(GL_VERSION);
 #if defined(IMGUI_IMPL_OPENGL_ES2)
     // GLES 2
     bd->GlVersion = 200;
     bd->GlProfileIsES2 = true;
 #else
     // Desktop or GLES 3
-    const char* gl_version_str = (const char*)glGetString(GL_VERSION);
     GLint major = 0;
     GLint minor = 0;
     glGetIntegerv(GL_MAJOR_VERSION, &major);
@@ -332,13 +342,14 @@ bool    ImGui_ImplOpenGL3_Init(const char* glsl_version)
 #endif
 
 #ifdef IMGUI_IMPL_OPENGL_DEBUG
-    printf("GlVersion = %d, \"%s\"\nGlProfileIsCompat = %d\nGlProfileMask = 0x%X\nGlProfileIsES2 = %d, GlProfileIsES3 = %d\nGL_VENDOR = '%s'\nGL_RENDERER = '%s'\n", bd->GlVersion, gl_version_str, bd->GlProfileIsCompat, bd->GlProfileMask, bd->GlProfileIsES2, bd->GlProfileIsES3, (const char*)glGetString(GL_VENDOR), (const char*)glGetString(GL_RENDERER)); // [DEBUG]
+    printf("GlVersion = %d, \"%s\"\nGlProfileIsCompat = %d\nGlProfileMask = 0x%X\nGlProfileIsES2/IsEs3 = %d/%d\nGL_VENDOR = '%s'\nGL_RENDERER = '%s'\n", bd->GlVersion, gl_version_str, bd->GlProfileIsCompat, bd->GlProfileMask, bd->GlProfileIsES2, bd->GlProfileIsES3, (const char*)glGetString(GL_VENDOR), (const char*)glGetString(GL_RENDERER)); // [DEBUG]
 #endif
 
 #ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_VTX_OFFSET
     if (bd->GlVersion >= 320)
         io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset;  // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
 #endif
+    io.BackendFlags |= ImGuiBackendFlags_RendererHasViewports;  // We can create multi-viewports on the Renderer side (optional)
 
     // Store GLSL version string so we can refer to it later in case we recreate shaders.
     // Note: GLSL version is NOT the same as GL version. Leave this to nullptr if unsure.
@@ -379,6 +390,8 @@ bool    ImGui_ImplOpenGL3_Init(const char* glsl_version)
     }
 #endif
 
+    ImGui_ImplOpenGL3_InitMultiViewportSupport();
+
     return true;
 }
 
@@ -388,10 +401,11 @@ void    ImGui_ImplOpenGL3_Shutdown()
     IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
     ImGuiIO& io = ImGui::GetIO();
 
+    ImGui_ImplOpenGL3_ShutdownMultiViewportSupport();
     ImGui_ImplOpenGL3_DestroyDeviceObjects();
     io.BackendRendererName = nullptr;
     io.BackendRendererUserData = nullptr;
-    io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset;
+    io.BackendFlags &= ~(ImGuiBackendFlags_RendererHasVtxOffset | ImGuiBackendFlags_RendererHasViewports);
     IM_DELETE(bd);
 }
 
@@ -402,6 +416,8 @@ void    ImGui_ImplOpenGL3_NewFrame()
 
     if (!bd->ShaderHandle)
         ImGui_ImplOpenGL3_CreateDeviceObjects();
+    if (!bd->FontTexture)
+        ImGui_ImplOpenGL3_CreateFontsTexture();
 }
 
 static void ImGui_ImplOpenGL3_SetupRenderState(ImDrawData* draw_data, int fb_width, int fb_height, GLuint vertex_array_object)
@@ -546,7 +562,7 @@ void    ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data)
     // Render command lists
     for (int n = 0; n < draw_data->CmdListsCount; n++)
     {
-        const ImDrawList* cmd_list = draw_data->CmdLists[n];
+        const ImDrawList* draw_list = draw_data->CmdLists[n];
 
         // Upload vertex/index buffers
         // - OpenGL drivers are in a very sorry state nowadays....
@@ -556,8 +572,8 @@ void    ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data)
         // - We are now back to using exclusively glBufferData(). So bd->UseBufferSubData IS ALWAYS FALSE in this code.
         //   We are keeping the old code path for a while in case people finding new issues may want to test the bd->UseBufferSubData path.
         // - See https://github.com/ocornut/imgui/issues/4468 and please report any corruption issues.
-        const GLsizeiptr vtx_buffer_size = (GLsizeiptr)cmd_list->VtxBuffer.Size * (int)sizeof(ImDrawVert);
-        const GLsizeiptr idx_buffer_size = (GLsizeiptr)cmd_list->IdxBuffer.Size * (int)sizeof(ImDrawIdx);
+        const GLsizeiptr vtx_buffer_size = (GLsizeiptr)draw_list->VtxBuffer.Size * (int)sizeof(ImDrawVert);
+        const GLsizeiptr idx_buffer_size = (GLsizeiptr)draw_list->IdxBuffer.Size * (int)sizeof(ImDrawIdx);
         if (bd->UseBufferSubData)
         {
             if (bd->VertexBufferSize < vtx_buffer_size)
@@ -570,18 +586,18 @@ void    ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data)
                 bd->IndexBufferSize = idx_buffer_size;
                 GL_CALL(glBufferData(GL_ELEMENT_ARRAY_BUFFER, bd->IndexBufferSize, nullptr, GL_STREAM_DRAW));
             }
-            GL_CALL(glBufferSubData(GL_ARRAY_BUFFER, 0, vtx_buffer_size, (const GLvoid*)cmd_list->VtxBuffer.Data));
-            GL_CALL(glBufferSubData(GL_ELEMENT_ARRAY_BUFFER, 0, idx_buffer_size, (const GLvoid*)cmd_list->IdxBuffer.Data));
+            GL_CALL(glBufferSubData(GL_ARRAY_BUFFER, 0, vtx_buffer_size, (const GLvoid*)draw_list->VtxBuffer.Data));
+            GL_CALL(glBufferSubData(GL_ELEMENT_ARRAY_BUFFER, 0, idx_buffer_size, (const GLvoid*)draw_list->IdxBuffer.Data));
         }
         else
         {
-            GL_CALL(glBufferData(GL_ARRAY_BUFFER, vtx_buffer_size, (const GLvoid*)cmd_list->VtxBuffer.Data, GL_STREAM_DRAW));
-            GL_CALL(glBufferData(GL_ELEMENT_ARRAY_BUFFER, idx_buffer_size, (const GLvoid*)cmd_list->IdxBuffer.Data, GL_STREAM_DRAW));
+            GL_CALL(glBufferData(GL_ARRAY_BUFFER, vtx_buffer_size, (const GLvoid*)draw_list->VtxBuffer.Data, GL_STREAM_DRAW));
+            GL_CALL(glBufferData(GL_ELEMENT_ARRAY_BUFFER, idx_buffer_size, (const GLvoid*)draw_list->IdxBuffer.Data, GL_STREAM_DRAW));
         }
 
-        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        for (int cmd_i = 0; cmd_i < draw_list->CmdBuffer.Size; cmd_i++)
         {
-            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            const ImDrawCmd* pcmd = &draw_list->CmdBuffer[cmd_i];
             if (pcmd->UserCallback != nullptr)
             {
                 // User callback, registered via ImDrawList::AddCallback()
@@ -589,7 +605,7 @@ void    ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data)
                 if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
                     ImGui_ImplOpenGL3_SetupRenderState(draw_data, fb_width, fb_height, vertex_array_object);
                 else
-                    pcmd->UserCallback(cmd_list, pcmd);
+                    pcmd->UserCallback(draw_list, pcmd);
             }
             else
             {
@@ -677,12 +693,14 @@ bool ImGui_ImplOpenGL3_CreateFontsTexture()
     GL_CALL(glBindTexture(GL_TEXTURE_2D, bd->FontTexture));
     GL_CALL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR));
     GL_CALL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR));
+    GL_CALL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE));
+    GL_CALL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE));
 #ifdef GL_UNPACK_ROW_LENGTH // Not on WebGL/ES
     GL_CALL(glPixelStorei(GL_UNPACK_ROW_LENGTH, 0));
 #endif
     GL_CALL(glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixels));
 
-    // Store our identifier
+    // Store identifier
     io.Fonts->SetTexID((ImTextureID)(intptr_t)bd->FontTexture);
 
     // Restore state
@@ -888,13 +906,15 @@ bool    ImGui_ImplOpenGL3_CreateDeviceObjects()
 
     // Create shaders
     const GLchar* vertex_shader_with_version[2] = { bd->GlslVersionString, vertex_shader };
-    GLuint vert_handle = glCreateShader(GL_VERTEX_SHADER);
+    GLuint vert_handle;
+    GL_CALL(vert_handle = glCreateShader(GL_VERTEX_SHADER));
     glShaderSource(vert_handle, 2, vertex_shader_with_version, nullptr);
     glCompileShader(vert_handle);
     CheckShader(vert_handle, "vertex shader");
 
     const GLchar* fragment_shader_with_version[2] = { bd->GlslVersionString, fragment_shader };
-    GLuint frag_handle = glCreateShader(GL_FRAGMENT_SHADER);
+    GLuint frag_handle;
+    GL_CALL(frag_handle = glCreateShader(GL_FRAGMENT_SHADER));
     glShaderSource(frag_handle, 2, fragment_shader_with_version, nullptr);
     glCompileShader(frag_handle);
     CheckShader(frag_handle, "fragment shader");
@@ -945,6 +965,34 @@ void    ImGui_ImplOpenGL3_DestroyDeviceObjects()
     ImGui_ImplOpenGL3_DestroyFontsTexture();
 }
 
+//--------------------------------------------------------------------------------------------------------
+// MULTI-VIEWPORT / PLATFORM INTERFACE SUPPORT
+// This is an _advanced_ and _optional_ feature, allowing the backend to create and handle multiple viewports simultaneously.
+// If you are new to dear imgui or creating a new binding for dear imgui, it is recommended that you completely ignore this section first..
+//--------------------------------------------------------------------------------------------------------
+
+static void ImGui_ImplOpenGL3_RenderWindow(ImGuiViewport* viewport, void*)
+{
+    if (!(viewport->Flags & ImGuiViewportFlags_NoRendererClear))
+    {
+        ImVec4 clear_color = ImVec4(0.0f, 0.0f, 0.0f, 1.0f);
+        glClearColor(clear_color.x, clear_color.y, clear_color.z, clear_color.w);
+        glClear(GL_COLOR_BUFFER_BIT);
+    }
+    ImGui_ImplOpenGL3_RenderDrawData(viewport->DrawData);
+}
+
+static void ImGui_ImplOpenGL3_InitMultiViewportSupport()
+{
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    platform_io.Renderer_RenderWindow = ImGui_ImplOpenGL3_RenderWindow;
+}
+
+static void ImGui_ImplOpenGL3_ShutdownMultiViewportSupport()
+{
+    ImGui::DestroyPlatformWindows();
+}
+
 //-----------------------------------------------------------------------------
 
 #if defined(__GNUC__)

backends/imgui_impl_opengl3.h

@@ -5,7 +5,8 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'GLuint' OpenGL texture identifier as void*/ImTextureID. Read the FAQ about ImTextureID!
-//  [x] Renderer: Large meshes support (64k+ vertices) with 16-bit indices (Desktop OpenGL only).
+//  [x] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset) [Desktop OpenGL only!]
+//  [X] Renderer: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
 
 // About WebGL/ES:
 // - You need to '#define IMGUI_IMPL_OPENGL_ES2' or '#define IMGUI_IMPL_OPENGL_ES3' to use WebGL or OpenGL ES.
@@ -29,7 +30,7 @@
 #include "imgui.h"      // IMGUI_IMPL_API
 #ifndef IMGUI_DISABLE
 
-// Backend API
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
 IMGUI_IMPL_API bool     ImGui_ImplOpenGL3_Init(const char* glsl_version = nullptr);
 IMGUI_IMPL_API void     ImGui_ImplOpenGL3_Shutdown();
 IMGUI_IMPL_API void     ImGui_ImplOpenGL3_NewFrame();

backends/imgui_impl_opengl3_loader.h

@@ -181,6 +181,9 @@ typedef khronos_uint8_t GLubyte;
 #define GL_LINEAR                         0x2601
 #define GL_TEXTURE_MAG_FILTER             0x2800
 #define GL_TEXTURE_MIN_FILTER             0x2801
+#define GL_TEXTURE_WRAP_S                 0x2802
+#define GL_TEXTURE_WRAP_T                 0x2803
+#define GL_REPEAT                         0x2901
 typedef void (APIENTRYP PFNGLPOLYGONMODEPROC) (GLenum face, GLenum mode);
 typedef void (APIENTRYP PFNGLSCISSORPROC) (GLint x, GLint y, GLsizei width, GLsizei height);
 typedef void (APIENTRYP PFNGLTEXPARAMETERIPROC) (GLenum target, GLenum pname, GLint param);
@@ -231,6 +234,9 @@ GLAPI void APIENTRY glDeleteTextures (GLsizei n, const GLuint *textures);
 GLAPI void APIENTRY glGenTextures (GLsizei n, GLuint *textures);
 #endif
 #endif /* GL_VERSION_1_1 */
+#ifndef GL_VERSION_1_2
+#define GL_CLAMP_TO_EDGE                  0x812F
+#endif /* GL_VERSION_1_2 */
 #ifndef GL_VERSION_1_3
 #define GL_TEXTURE0                       0x84C0
 #define GL_ACTIVE_TEXTURE                 0x84E0

backends/imgui_impl_osx.h

@@ -4,12 +4,16 @@
 // - Requires linking with the GameController framework ("-framework GameController").
 
 // Implemented features:
-//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+//  [X] Platform: Clipboard support is part of core Dear ImGui (no specific code in this backend).
 //  [X] Platform: Mouse support. Can discriminate Mouse/Pen.
-//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy kVK_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
-//  [X] Platform: OSX clipboard is supported within core Dear ImGui (no specific code in this backend).
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy kVK_* values are obsolete since 1.87 and not supported since 1.91.5]
 //  [X] Platform: Gamepad support. Enabled with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
+//  [X] Platform: Mouse cursor shape and visibility (ImGuiBackendFlags_HasMouseCursors). Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
 //  [X] Platform: IME support.
+//  [x] Platform: Multi-viewport / platform windows.
+// Issues:
+//  [ ] Platform: Multi-viewport: Window size not correctly reported when enabling io.ConfigViewportsNoDecoration
+//  [ ] Platform: Multi-viewport: ParentViewportID not honored, and so io.ConfigViewportsNoDefaultParent has no effect (minor).
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -27,6 +31,7 @@
 @class NSEvent;
 @class NSView;
 
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
 IMGUI_IMPL_API bool     ImGui_ImplOSX_Init(NSView* _Nonnull view);
 IMGUI_IMPL_API void     ImGui_ImplOSX_Shutdown();
 IMGUI_IMPL_API void     ImGui_ImplOSX_NewFrame(NSView* _Nullable view);
@@ -41,6 +46,7 @@ IMGUI_IMPL_API void     ImGui_ImplOSX_NewFrame(NSView* _Nullable view);
 // #include <AppKit/AppKit.hpp>
 #ifndef __OBJC__
 
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
 IMGUI_IMPL_API bool     ImGui_ImplOSX_Init(void* _Nonnull view);
 IMGUI_IMPL_API void     ImGui_ImplOSX_Shutdown();
 IMGUI_IMPL_API void     ImGui_ImplOSX_NewFrame(void* _Nullable view);

backends/imgui_impl_osx.mm

@@ -4,12 +4,16 @@
 // - Requires linking with the GameController framework ("-framework GameController").
 
 // Implemented features:
-//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+//  [X] Platform: Clipboard support is part of core Dear ImGui (no specific code in this backend).
 //  [X] Platform: Mouse support. Can discriminate Mouse/Pen.
-//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy kVK_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
-//  [X] Platform: OSX clipboard is supported within core Dear ImGui (no specific code in this backend).
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy kVK_* values are obsolete since 1.87 and not supported since 1.91.5]
 //  [X] Platform: Gamepad support. Enabled with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
+//  [X] Platform: Mouse cursor shape and visibility (ImGuiBackendFlags_HasMouseCursors). Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
 //  [X] Platform: IME support.
+//  [x] Platform: Multi-viewport / platform windows.
+// Issues:
+//  [ ] Platform: Multi-viewport: Window size not correctly reported when enabling io.ConfigViewportsNoDecoration
+//  [ ] Platform: Multi-viewport: ParentViewportID not honored, and so io.ConfigViewportsNoDefaultParent has no effect (minor).
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -29,6 +33,12 @@
 
 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
+//  2024-XX-XX: Added support for multiple windows via the ImGuiPlatformIO interface.
+//  2024-08-22: moved some OS/backend related function pointers from ImGuiIO to ImGuiPlatformIO:
+//               - io.GetClipboardTextFn    -> platform_io.Platform_GetClipboardTextFn
+//               - io.SetClipboardTextFn    -> platform_io.Platform_SetClipboardTextFn
+//               - io.PlatformSetImeDataFn  -> platform_io.Platform_SetImeDataFn
+//  2024-07-02: Update for io.SetPlatformImeDataFn() -> io.PlatformSetImeDataFn() renaming in main library.
 //  2023-10-05: Inputs: Added support for extra ImGuiKey values: F13 to F20 function keys. Stopped mapping F13 into PrintScreen.
 //  2023-04-09: Inputs: Added support for io.AddMouseSourceEvent() to discriminate ImGuiMouseSource_Mouse/ImGuiMouseSource_Pen.
 //  2023-02-01: Fixed scroll wheel scaling for devices emitting events with hasPreciseScrollingDeltas==false (e.g. non-Apple mices).
@@ -80,8 +90,9 @@ struct ImGui_ImplOSX_Data
     KeyEventResponder*          KeyEventResponder;
     NSTextInputContext*         InputContext;
     id                          Monitor;
+    NSWindow*                   Window;
 
-    ImGui_ImplOSX_Data()        { memset(this, 0, sizeof(*this)); }
+    ImGui_ImplOSX_Data()        { memset((void*)this, 0, sizeof(*this)); }
 };
 
 static ImGui_ImplOSX_Data*      ImGui_ImplOSX_GetBackendData()      { return (ImGui_ImplOSX_Data*)ImGui::GetIO().BackendPlatformUserData; }
@@ -90,6 +101,9 @@ static void                     ImGui_ImplOSX_DestroyBackendData()  { IM_DELETE(
 static inline CFTimeInterval    GetMachAbsoluteTimeInSeconds()      { return (CFTimeInterval)(double)(clock_gettime_nsec_np(CLOCK_UPTIME_RAW) / 1e9); }
 
 // Forward Declarations
+static void ImGui_ImplOSX_InitMultiViewportSupport();
+static void ImGui_ImplOSX_ShutdownMultiViewportSupport();
+static void ImGui_ImplOSX_UpdateMonitors();
 static void ImGui_ImplOSX_AddTrackingArea(NSView* _Nonnull view);
 static bool ImGui_ImplOSX_HandleEvent(NSEvent* event, NSView* view);
 
@@ -133,12 +147,28 @@ static bool ImGui_ImplOSX_HandleEvent(NSEvent* event, NSView* view);
 
 - (void)updateImePosWithView:(NSView *)view
 {
-    NSWindow *window = view.window;
+    NSWindow* window = view.window;
     if (!window)
         return;
-    NSRect contentRect = [window contentRectForFrameRect:window.frame];
-    NSRect rect = NSMakeRect(_posX, contentRect.size.height - _posY, 0, 0);
-    _imeRect = [window convertRectToScreen:rect];
+
+    ImGuiIO& io = ImGui::GetIO();
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        NSRect frame = window.frame;
+        NSRect contentRect = window.contentLayoutRect;
+        if (window.styleMask & NSWindowStyleMaskFullSizeContentView) // No title bar windows should be considered.
+            contentRect = frame;
+
+        NSRect firstScreenFrame = NSScreen.screens[0].frame;
+        _imeRect = NSMakeRect(_posX, _posY, 0, 0);
+        _imeRect.origin.y = firstScreenFrame.size.height - _imeRect.size.height - _imeRect.origin.y; // Opposite of ConvertNSRect()
+    }
+    else
+    {
+        NSRect contentRect = [window contentRectForFrameRect:window.frame];
+        NSRect rect = NSMakeRect(_posX, contentRect.size.height - _posY, 0, 0);
+        _imeRect = [window convertRectToScreen:rect];
+    }
 }
 
 - (void)viewDidMoveToWindow
@@ -233,6 +263,7 @@ static bool ImGui_ImplOSX_HandleEvent(NSEvent* event, NSView* view);
 
 - (void)onApplicationBecomeActive:(NSNotification*)aNotification;
 - (void)onApplicationBecomeInactive:(NSNotification*)aNotification;
+- (void)displaysDidChange:(NSNotification*)aNotification;
 
 @end
 
@@ -250,10 +281,18 @@ static bool ImGui_ImplOSX_HandleEvent(NSEvent* event, NSView* view);
     io.AddFocusEvent(false);
 }
 
+- (void)displaysDidChange:(NSNotification*)aNotification
+{
+    ImGui_ImplOSX_UpdateMonitors();
+}
+
 @end
 
 // Functions
-static ImGuiKey ImGui_ImplOSX_KeyCodeToImGuiKey(int key_code)
+
+// Not static to allow third-party code to use that if they want to (but undocumented)
+ImGuiKey ImGui_ImplOSX_KeyCodeToImGuiKey(int key_code);
+ImGuiKey ImGui_ImplOSX_KeyCodeToImGuiKey(int key_code)
 {
     switch (key_code)
     {
@@ -391,6 +430,7 @@ IMGUI_IMPL_API void ImGui_ImplOSX_NewFrame(void* _Nullable view) {
 bool ImGui_ImplOSX_Init(NSView* view)
 {
     ImGuiIO& io = ImGui::GetIO();
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
     IMGUI_CHECKVERSION();
     IM_ASSERT(io.BackendPlatformUserData == nullptr && "Already initialized a platform backend!");
 
@@ -400,8 +440,15 @@ bool ImGui_ImplOSX_Init(NSView* view)
     io.BackendPlatformName = "imgui_impl_osx";
     io.BackendFlags |= ImGuiBackendFlags_HasMouseCursors;           // We can honor GetMouseCursor() values (optional)
     //io.BackendFlags |= ImGuiBackendFlags_HasSetMousePos;          // We can honor io.WantSetMousePos requests (optional, rarely used)
+    io.BackendFlags |= ImGuiBackendFlags_PlatformHasViewports;      // We can create multi-viewports on the Platform side (optional)
+    //io.BackendFlags |= ImGuiBackendFlags_HasMouseHoveredViewport; // We can call io.AddMouseViewportEvent() with correct data (optional)
 
     bd->Observer = [ImGuiObserver new];
+    bd->Window = view.window ?: NSApp.orderedWindows.firstObject;
+    ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+    main_viewport->PlatformHandle = main_viewport->PlatformHandleRaw = (__bridge_retained void*)bd->Window;
+    ImGui_ImplOSX_UpdateMonitors();
+    ImGui_ImplOSX_InitMultiViewportSupport();
 
     // Load cursors. Some of them are undocumented.
     bd->MouseCursorHidden = false;
@@ -418,14 +465,14 @@ bool ImGui_ImplOSX_Init(NSView* view)
     // Note that imgui.cpp also include default OSX clipboard handlers which can be enabled
     // by adding '#define IMGUI_ENABLE_OSX_DEFAULT_CLIPBOARD_FUNCTIONS' in imconfig.h and adding '-framework ApplicationServices' to your linker command-line.
     // Since we are already in ObjC land here, it is easy for us to add a clipboard handler using the NSPasteboard api.
-    io.SetClipboardTextFn = [](void*, const char* str) -> void
+    platform_io.Platform_SetClipboardTextFn = [](ImGuiContext*, const char* str) -> void
     {
         NSPasteboard* pasteboard = [NSPasteboard generalPasteboard];
         [pasteboard declareTypes:[NSArray arrayWithObject:NSPasteboardTypeString] owner:nil];
         [pasteboard setString:[NSString stringWithUTF8String:str] forType:NSPasteboardTypeString];
     };
 
-    io.GetClipboardTextFn = [](void*) -> const char*
+    platform_io.Platform_GetClipboardTextFn = [](ImGuiContext*) -> const char*
     {
         NSPasteboard* pasteboard = [NSPasteboard generalPasteboard];
         NSString* available = [pasteboard availableTypeFromArray: [NSArray arrayWithObject:NSPasteboardTypeString]];
@@ -460,7 +507,7 @@ bool ImGui_ImplOSX_Init(NSView* view)
     [view addSubview:bd->KeyEventResponder];
     ImGui_ImplOSX_AddTrackingArea(view);
 
-    io.SetPlatformImeDataFn = [](ImGuiViewport* viewport, ImGuiPlatformImeData* data) -> void
+    platform_io.Platform_SetImeDataFn = [](ImGuiContext*, ImGuiViewport* viewport, ImGuiPlatformImeData* data) -> void
     {
         ImGui_ImplOSX_Data* bd = ImGui_ImplOSX_GetBackendData();
         if (data->WantVisible)
@@ -491,12 +538,12 @@ void ImGui_ImplOSX_Shutdown()
         bd->Monitor = nullptr;
     }
 
+    ImGui_ImplOSX_ShutdownMultiViewportSupport();
     ImGui_ImplOSX_DestroyBackendData();
-
     ImGuiIO& io = ImGui::GetIO();
     io.BackendPlatformName = nullptr;
     io.BackendPlatformUserData = nullptr;
-    io.BackendFlags &= ~(ImGuiBackendFlags_HasMouseCursors | ImGuiBackendFlags_HasGamepad);
+    io.BackendFlags &= ~(ImGuiBackendFlags_HasMouseCursors | ImGuiBackendFlags_HasGamepad | ImGuiBackendFlags_PlatformHasViewports);
 }
 
 static void ImGui_ImplOSX_UpdateMouseCursor()
@@ -673,14 +720,23 @@ static bool ImGui_ImplOSX_HandleEvent(NSEvent* event, NSView* view)
 
     if (event.type == NSEventTypeMouseMoved || event.type == NSEventTypeLeftMouseDragged || event.type == NSEventTypeRightMouseDragged || event.type == NSEventTypeOtherMouseDragged)
     {
-        NSPoint mousePoint = event.locationInWindow;
-        if (event.window == nil)
-            mousePoint = [[view window] convertPointFromScreen:mousePoint];
-        mousePoint = [view convertPoint:mousePoint fromView:nil];
-        if ([view isFlipped])
-            mousePoint = NSMakePoint(mousePoint.x, mousePoint.y);
+        NSPoint mousePoint;
+        if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+        {
+            mousePoint = NSEvent.mouseLocation;
+            mousePoint.y = CGDisplayPixelsHigh(kCGDirectMainDisplay) - mousePoint.y; // Normalize y coordinate to top-left of main display.
+        }
         else
-            mousePoint = NSMakePoint(mousePoint.x, view.bounds.size.height - mousePoint.y);
+        {
+            mousePoint = event.locationInWindow;
+            if (event.window == nil)
+                mousePoint = [[view window] convertPointFromScreen:mousePoint];
+            mousePoint = [view convertPoint:mousePoint fromView:nil]; // Convert to local coordinates of view
+            if ([view isFlipped])
+                mousePoint = NSMakePoint(mousePoint.x, mousePoint.y);
+            else
+                mousePoint = NSMakePoint(mousePoint.x, view.bounds.size.height - mousePoint.y);
+        }
         io.AddMouseSourceEvent(GetMouseSource(event));
         io.AddMousePosEvent((float)mousePoint.x, (float)mousePoint.y);
         return io.WantCaptureMouse;
@@ -808,6 +864,294 @@ static void ImGui_ImplOSX_AddTrackingArea(NSView* _Nonnull view)
     }];
 }
 
+//--------------------------------------------------------------------------------------------------------
+// MULTI-VIEWPORT / PLATFORM INTERFACE SUPPORT
+// This is an _advanced_ and _optional_ feature, allowing the back-end to create and handle multiple viewports simultaneously.
+// If you are new to dear imgui or creating a new binding for dear imgui, it is recommended that you completely ignore this section first..
+//--------------------------------------------------------------------------------------------------------
+
+struct ImGuiViewportDataOSX
+{
+    NSWindow*               Window;
+    bool                    WindowOwned;
+
+    ImGuiViewportDataOSX()  { WindowOwned = false; }
+    ~ImGuiViewportDataOSX() { IM_ASSERT(Window == nil); }
+};
+
+@interface ImGui_ImplOSX_Window: NSWindow
+@end
+
+@implementation ImGui_ImplOSX_Window
+
+- (BOOL)canBecomeKeyWindow
+{
+    return YES;
+}
+
+@end
+
+static void ConvertNSRect(NSRect* r)
+{
+    NSRect firstScreenFrame = NSScreen.screens[0].frame;
+    IM_ASSERT(firstScreenFrame.origin.x == 0 && firstScreenFrame.origin.y == 0);
+    r->origin.y = firstScreenFrame.size.height - r->origin.y - r->size.height;
+}
+
+static void ImGui_ImplOSX_CreateWindow(ImGuiViewport* viewport)
+{
+    ImGui_ImplOSX_Data* bd = ImGui_ImplOSX_GetBackendData();
+    ImGuiViewportDataOSX* data = IM_NEW(ImGuiViewportDataOSX)();
+    viewport->PlatformUserData = data;
+
+    NSScreen* screen = bd->Window.screen;
+    NSRect rect = NSMakeRect(viewport->Pos.x, viewport->Pos.y, viewport->Size.x, viewport->Size.y);
+    ConvertNSRect(&rect);
+
+    NSWindowStyleMask styleMask = 0;
+    if (viewport->Flags & ImGuiViewportFlags_NoDecoration)
+        styleMask |= NSWindowStyleMaskBorderless;
+    else
+        styleMask |= NSWindowStyleMaskTitled | NSWindowStyleMaskResizable | NSWindowStyleMaskClosable | NSWindowStyleMaskMiniaturizable;
+
+    NSWindow* window = [[ImGui_ImplOSX_Window alloc] initWithContentRect:rect
+                                                               styleMask:styleMask
+                                                                 backing:NSBackingStoreBuffered
+                                                                   defer:YES
+                                                                  screen:screen];
+    if (viewport->Flags & ImGuiViewportFlags_TopMost)
+        [window setLevel:NSFloatingWindowLevel];
+
+    window.title = @"Untitled";
+    window.opaque = YES;
+
+    KeyEventResponder* view = [[KeyEventResponder alloc] initWithFrame:rect];
+    if (floor(NSAppKitVersionNumber) > NSAppKitVersionNumber10_6 && ceil(NSAppKitVersionNumber) < NSAppKitVersionNumber10_15)
+        [view setWantsBestResolutionOpenGLSurface:YES];
+
+    window.contentView = view;
+
+    data->Window = window;
+    data->WindowOwned = true;
+    viewport->PlatformRequestResize = false;
+    viewport->PlatformHandle = viewport->PlatformHandleRaw = (__bridge_retained void*)window;
+}
+
+static void ImGui_ImplOSX_DestroyWindow(ImGuiViewport* viewport)
+{
+    NSWindow* window = (__bridge_transfer NSWindow*)viewport->PlatformHandleRaw;
+    window = nil;
+
+    if (ImGuiViewportDataOSX* data = (ImGuiViewportDataOSX*)viewport->PlatformUserData)
+    {
+        NSWindow* window = data->Window;
+        if (window != nil && data->WindowOwned)
+        {
+            window.contentView = nil;
+            window.contentViewController = nil;
+            [window orderOut:nil];
+        }
+        data->Window = nil;
+        IM_DELETE(data);
+    }
+    viewport->PlatformUserData = viewport->PlatformHandle = viewport->PlatformHandleRaw = nullptr;
+}
+
+static void ImGui_ImplOSX_ShowWindow(ImGuiViewport* viewport)
+{
+    ImGuiViewportDataOSX* data = (ImGuiViewportDataOSX*)viewport->PlatformUserData;
+    IM_ASSERT(data->Window != 0);
+
+    if (viewport->Flags & ImGuiViewportFlags_NoFocusOnAppearing)
+        [data->Window orderFront:nil];
+    else
+        [data->Window makeKeyAndOrderFront:nil];
+
+    [data->Window setIsVisible:YES];
+}
+
+static ImVec2 ImGui_ImplOSX_GetWindowPos(ImGuiViewport* viewport)
+{
+    ImGuiViewportDataOSX* data = (ImGuiViewportDataOSX*)viewport->PlatformUserData;
+    IM_ASSERT(data->Window != 0);
+
+    NSWindow* window = data->Window;
+    NSRect frame = window.frame;
+    NSRect contentRect = window.contentLayoutRect;
+    if (window.styleMask & NSWindowStyleMaskFullSizeContentView) // No title bar windows should be considered.
+        contentRect = frame;
+
+    NSRect firstScreenFrame = NSScreen.screens[0].frame;
+    return ImVec2(frame.origin.x, firstScreenFrame.size.height - frame.origin.y - contentRect.size.height);
+}
+
+static void ImGui_ImplOSX_SetWindowPos(ImGuiViewport* viewport, ImVec2 pos)
+{
+    ImGuiViewportDataOSX* data = (ImGuiViewportDataOSX*)viewport->PlatformUserData;
+    IM_ASSERT(data->Window != 0);
+
+    NSWindow* window = data->Window;
+    NSSize size = window.frame.size;
+
+    NSRect r = NSMakeRect(pos.x, pos.y, size.width, size.height);
+    ConvertNSRect(&r);
+    [window setFrameOrigin:r.origin];
+}
+
+static ImVec2 ImGui_ImplOSX_GetWindowSize(ImGuiViewport* viewport)
+{
+    ImGuiViewportDataOSX* data = (ImGuiViewportDataOSX*)viewport->PlatformUserData;
+    IM_ASSERT(data->Window != 0);
+
+    NSWindow* window = data->Window;
+    NSSize size = window.contentLayoutRect.size;
+    return ImVec2(size.width, size.height);
+}
+
+static void ImGui_ImplOSX_SetWindowSize(ImGuiViewport* viewport, ImVec2 size)
+{
+    ImGuiViewportDataOSX* data = (ImGuiViewportDataOSX*)viewport->PlatformUserData;
+    IM_ASSERT(data->Window != 0);
+
+    NSWindow* window = data->Window;
+    NSRect rect = window.frame;
+    rect.origin.y -= (size.y - rect.size.height);
+    rect.size.width = size.x;
+    rect.size.height = size.y;
+    [window setFrame:rect display:YES];
+}
+
+static void ImGui_ImplOSX_SetWindowFocus(ImGuiViewport* viewport)
+{
+    ImGui_ImplOSX_Data* bd = ImGui_ImplOSX_GetBackendData();
+    ImGuiViewportDataOSX* data = (ImGuiViewportDataOSX*)viewport->PlatformUserData;
+    IM_ASSERT(data->Window != 0);
+    [data->Window makeKeyAndOrderFront:bd->Window];
+}
+
+static bool ImGui_ImplOSX_GetWindowFocus(ImGuiViewport* viewport)
+{
+    ImGuiViewportDataOSX* data = (ImGuiViewportDataOSX*)viewport->PlatformUserData;
+    IM_ASSERT(data->Window != 0);
+
+    return data->Window.isKeyWindow;
+}
+
+static bool ImGui_ImplOSX_GetWindowMinimized(ImGuiViewport* viewport)
+{
+    ImGuiViewportDataOSX* data = (ImGuiViewportDataOSX*)viewport->PlatformUserData;
+    IM_ASSERT(data->Window != 0);
+
+    return data->Window.isMiniaturized;
+}
+
+static void ImGui_ImplOSX_SetWindowTitle(ImGuiViewport* viewport, const char* title)
+{
+    ImGuiViewportDataOSX* data = (ImGuiViewportDataOSX*)viewport->PlatformUserData;
+    IM_ASSERT(data->Window != 0);
+
+    data->Window.title = [NSString stringWithUTF8String:title];
+}
+
+static void ImGui_ImplOSX_SetWindowAlpha(ImGuiViewport* viewport, float alpha)
+{
+    ImGuiViewportDataOSX* data = (ImGuiViewportDataOSX*)viewport->PlatformUserData;
+    IM_ASSERT(data->Window != 0);
+    IM_ASSERT(alpha >= 0.0f && alpha <= 1.0f);
+
+    data->Window.alphaValue = alpha;
+}
+
+static float ImGui_ImplOSX_GetWindowDpiScale(ImGuiViewport* viewport)
+{
+    ImGuiViewportDataOSX* data = (ImGuiViewportDataOSX*)viewport->PlatformUserData;
+    IM_ASSERT(data->Window != 0);
+
+    return data->Window.backingScaleFactor;
+}
+
+static void ImGui_ImplOSX_UpdateMonitors()
+{
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    platform_io.Monitors.resize(0);
+
+    NSRect firstScreenFrame = NSScreen.screens[0].frame;
+    IM_ASSERT(firstScreenFrame.origin.x == 0 && firstScreenFrame.origin.y == 0);
+
+    for (NSScreen* screen in NSScreen.screens)
+    {
+        NSRect frame = screen.frame;
+        NSRect visibleFrame = screen.visibleFrame;
+        ConvertNSRect(&frame);
+        ConvertNSRect(&visibleFrame);
+
+        ImGuiPlatformMonitor imgui_monitor;
+        imgui_monitor.MainPos = ImVec2(frame.origin.x, frame.origin.y);
+        imgui_monitor.MainSize = ImVec2(frame.size.width, frame.size.height);
+        imgui_monitor.WorkPos = ImVec2(visibleFrame.origin.x, visibleFrame.origin.y);
+        imgui_monitor.WorkSize = ImVec2(visibleFrame.size.width, visibleFrame.size.height);
+        imgui_monitor.DpiScale = screen.backingScaleFactor;
+        imgui_monitor.PlatformHandle = (__bridge_retained void*)screen;
+
+        platform_io.Monitors.push_back(imgui_monitor);
+    }
+}
+
+static void ImGui_ImplOSX_InitMultiViewportSupport()
+{
+    ImGui_ImplOSX_Data* bd = ImGui_ImplOSX_GetBackendData();
+
+    // Register platform interface (will be coupled with a renderer interface)
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    platform_io.Platform_CreateWindow = ImGui_ImplOSX_CreateWindow;
+    platform_io.Platform_DestroyWindow = ImGui_ImplOSX_DestroyWindow;
+    platform_io.Platform_ShowWindow = ImGui_ImplOSX_ShowWindow;
+    platform_io.Platform_SetWindowPos = ImGui_ImplOSX_SetWindowPos;
+    platform_io.Platform_GetWindowPos = ImGui_ImplOSX_GetWindowPos;
+    platform_io.Platform_SetWindowSize = ImGui_ImplOSX_SetWindowSize;
+    platform_io.Platform_GetWindowSize = ImGui_ImplOSX_GetWindowSize;
+    platform_io.Platform_SetWindowFocus = ImGui_ImplOSX_SetWindowFocus;
+    platform_io.Platform_GetWindowFocus = ImGui_ImplOSX_GetWindowFocus;
+    platform_io.Platform_GetWindowMinimized = ImGui_ImplOSX_GetWindowMinimized;
+    platform_io.Platform_SetWindowTitle = ImGui_ImplOSX_SetWindowTitle;
+    platform_io.Platform_SetWindowAlpha = ImGui_ImplOSX_SetWindowAlpha;
+    platform_io.Platform_GetWindowDpiScale = ImGui_ImplOSX_GetWindowDpiScale; // FIXME-DPI
+
+    // Register main window handle (which is owned by the main application, not by us)
+    ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+    ImGuiViewportDataOSX* data = IM_NEW(ImGuiViewportDataOSX)();
+    data->Window = bd->Window;
+    data->WindowOwned = false;
+    main_viewport->PlatformUserData = data;
+    main_viewport->PlatformHandle = (__bridge void*)bd->Window;
+
+    [NSNotificationCenter.defaultCenter addObserver:bd->Observer
+                                           selector:@selector(displaysDidChange:)
+                                               name:NSApplicationDidChangeScreenParametersNotification
+                                             object:nil];
+}
+
+static void ImGui_ImplOSX_ShutdownMultiViewportSupport()
+{
+    ImGui_ImplOSX_Data* bd = ImGui_ImplOSX_GetBackendData();
+    [NSNotificationCenter.defaultCenter removeObserver:bd->Observer
+                                                  name:NSApplicationDidChangeScreenParametersNotification
+                                                object:nil];
+    bd->Observer = nullptr;
+    bd->Window = nullptr;
+    if (bd->Monitor != nullptr)
+    {
+        [NSEvent removeMonitor:bd->Monitor];
+        bd->Monitor = nullptr;
+    }
+
+    ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+    ImGuiViewportDataOSX* data = (ImGuiViewportDataOSX*)main_viewport->PlatformUserData;
+    IM_DELETE(data);
+    main_viewport->PlatformUserData = nullptr;
+    ImGui::DestroyPlatformWindows();
+}
+
 //-----------------------------------------------------------------------------
 
 #endif // #ifndef IMGUI_DISABLE

backends/imgui_impl_sdl2.cpp

@@ -6,10 +6,14 @@
 // Implemented features:
 //  [X] Platform: Clipboard support.
 //  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen.
-//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy SDL_SCANCODE_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy SDL_SCANCODE_* values are obsolete since 1.87 and not supported since 1.91.5]
 //  [X] Platform: Gamepad support. Enabled with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
-//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+//  [X] Platform: Mouse cursor shape and visibility (ImGuiBackendFlags_HasMouseCursors). Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
 //  [X] Platform: Basic IME support. App needs to call 'SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1");' before SDL_CreateWindow()!.
+//  [X] Platform: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
+// Missing features or Issues:
+//  [ ] Platform: Multi-viewport: Minimized windows seems to break mouse wheel events (at least under Windows).
+//  [ ] Platform: Multi-viewport: ParentViewportID not honored, and so io.ConfigViewportsNoDefaultParent has no effect (minor).
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -21,6 +25,18 @@
 
 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
+//  2024-XX-XX: Platform: Added support for multiple windows via the ImGuiPlatformIO interface.
+//  2024-10-24: Emscripten: from SDL 2.30.9, SDL_EVENT_MOUSE_WHEEL event doesn't require dividing by 100.0f.
+//  2024-09-09: use SDL_Vulkan_GetDrawableSize() when available. (#7967, #3190)
+//  2024-08-22: moved some OS/backend related function pointers from ImGuiIO to ImGuiPlatformIO:
+//               - io.GetClipboardTextFn    -> platform_io.Platform_GetClipboardTextFn
+//               - io.SetClipboardTextFn    -> platform_io.Platform_SetClipboardTextFn
+//               - io.PlatformOpenInShellFn -> platform_io.Platform_OpenInShellFn
+//               - io.PlatformSetImeDataFn  -> platform_io.Platform_SetImeDataFn
+//  2024-08-19: Storing SDL's Uint32 WindowID inside ImGuiViewport::PlatformHandle instead of SDL_Window*.
+//  2024-08-19: ImGui_ImplSDL2_ProcessEvent() now ignores events intended for other SDL windows. (#7853)
+//  2024-07-02: Emscripten: Added io.PlatformOpenInShellFn() handler for Emscripten versions.
+//  2024-07-02: Update for io.SetPlatformImeDataFn() -> io.PlatformSetImeDataFn() renaming in main library.
 //  2024-02-14: Inputs: Handle gamepad disconnection. Added ImGui_ImplSDL2_SetGamepadMode().
 //  2023-10-05: Inputs: Added support for extra ImGuiKey values: F13 to F24 function keys, app back/forward keys.
 //  2023-04-06: Inputs: Avoid calling SDL_StartTextInput()/SDL_StopTextInput() as they don't only pertain to IME. It's unclear exactly what their relation is to IME. (#6306)
@@ -47,7 +63,7 @@
 //  2022-01-10: Inputs: calling new io.AddKeyEvent(), io.AddKeyModsEvent() + io.SetKeyEventNativeData() API (1.87+). Support for full ImGuiKey range.
 //  2021-08-17: Calling io.AddFocusEvent() on SDL_WINDOWEVENT_FOCUS_GAINED/SDL_WINDOWEVENT_FOCUS_LOST.
 //  2021-07-29: Inputs: MousePos is correctly reported when the host platform window is hovered but not focused (using SDL_GetMouseFocus() + SDL_HINT_MOUSE_FOCUS_CLICKTHROUGH, requires SDL 2.0.5+)
-//  2021-06-29: *BREAKING CHANGE* Removed 'SDL_Window* window' parameter to ImGui_ImplSDL2_NewFrame() which was unnecessary.
+//  2021-06:29: *BREAKING CHANGE* Removed 'SDL_Window* window' parameter to ImGui_ImplSDL2_NewFrame() which was unnecessary.
 //  2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
 //  2021-03-22: Rework global mouse pos availability check listing supported platforms explicitly, effectively fixing mouse access on Raspberry Pi. (#2837, #3950)
 //  2020-05-25: Misc: Report a zero display-size when window is minimized, to be consistent with other backends.
@@ -88,26 +104,44 @@
 #endif
 
 // SDL
+// (the multi-viewports feature requires SDL features supported from SDL 2.0.4+. SDL 2.0.5+ is highly recommended)
 #include <SDL.h>
 #include <SDL_syswm.h>
-#if defined(__APPLE__)
+#ifdef __APPLE__
 #include <TargetConditionals.h>
 #endif
+#ifdef __EMSCRIPTEN__
+#include <emscripten/em_js.h>
+#endif
 
 #if SDL_VERSION_ATLEAST(2,0,4) && !defined(__EMSCRIPTEN__) && !defined(__ANDROID__) && !(defined(__APPLE__) && TARGET_OS_IOS) && !defined(__amigaos4__)
 #define SDL_HAS_CAPTURE_AND_GLOBAL_MOUSE    1
 #else
 #define SDL_HAS_CAPTURE_AND_GLOBAL_MOUSE    0
 #endif
+#define SDL_HAS_WINDOW_ALPHA                SDL_VERSION_ATLEAST(2,0,5)
+#define SDL_HAS_ALWAYS_ON_TOP               SDL_VERSION_ATLEAST(2,0,5)
+#define SDL_HAS_USABLE_DISPLAY_BOUNDS       SDL_VERSION_ATLEAST(2,0,5)
+#define SDL_HAS_PER_MONITOR_DPI             SDL_VERSION_ATLEAST(2,0,4)
 #define SDL_HAS_VULKAN                      SDL_VERSION_ATLEAST(2,0,6)
+#define SDL_HAS_DISPLAY_EVENT               SDL_VERSION_ATLEAST(2,0,9)
+#define SDL_HAS_SHOW_WINDOW_ACTIVATION_HINT SDL_VERSION_ATLEAST(2,0,18)
+#if SDL_HAS_VULKAN
+#include <SDL_vulkan.h>
+#else
+static const Uint32 SDL_WINDOW_VULKAN = 0x10000000;
+#endif
 
 // SDL Data
 struct ImGui_ImplSDL2_Data
 {
     SDL_Window*             Window;
+    Uint32                  WindowID;
     SDL_Renderer*           Renderer;
     Uint64                  Time;
     char*                   ClipboardTextData;
+    bool                    UseVulkan;
+    bool                    WantUpdateMonitors;
 
     // Mouse handling
     Uint32                  MouseWindowID;
@@ -116,6 +150,7 @@ struct ImGui_ImplSDL2_Data
     SDL_Cursor*             MouseLastCursor;
     int                     MouseLastLeaveFrame;
     bool                    MouseCanUseGlobalState;
+    bool                    MouseCanReportHoveredViewport;  // This is hard to use/unreliable on SDL so we'll set ImGuiBackendFlags_HasMouseHoveredViewport dynamically based on state.
 
     // Gamepad handling
     ImVector<SDL_GameController*> Gamepads;
@@ -134,8 +169,13 @@ static ImGui_ImplSDL2_Data* ImGui_ImplSDL2_GetBackendData()
     return ImGui::GetCurrentContext() ? (ImGui_ImplSDL2_Data*)ImGui::GetIO().BackendPlatformUserData : nullptr;
 }
 
+// Forward Declarations
+static void ImGui_ImplSDL2_UpdateMonitors();
+static void ImGui_ImplSDL2_InitMultiViewportSupport(SDL_Window* window, void* sdl_gl_context);
+static void ImGui_ImplSDL2_ShutdownMultiViewportSupport();
+
 // Functions
-static const char* ImGui_ImplSDL2_GetClipboardText(void*)
+static const char* ImGui_ImplSDL2_GetClipboardText(ImGuiContext*)
 {
     ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();
     if (bd->ClipboardTextData)
@@ -144,27 +184,30 @@ static const char* ImGui_ImplSDL2_GetClipboardText(void*)
     return bd->ClipboardTextData;
 }
 
-static void ImGui_ImplSDL2_SetClipboardText(void*, const char* text)
+static void ImGui_ImplSDL2_SetClipboardText(ImGuiContext*, const char* text)
 {
     SDL_SetClipboardText(text);
 }
 
 // Note: native IME will only display if user calls SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1") _before_ SDL_CreateWindow().
-static void ImGui_ImplSDL2_SetPlatformImeData(ImGuiViewport*, ImGuiPlatformImeData* data)
+static void ImGui_ImplSDL2_PlatformSetImeData(ImGuiContext*, ImGuiViewport* viewport, ImGuiPlatformImeData* data)
 {
     if (data->WantVisible)
     {
         SDL_Rect r;
-        r.x = (int)data->InputPos.x;
-        r.y = (int)data->InputPos.y;
+        r.x = (int)(data->InputPos.x - viewport->Pos.x);
+        r.y = (int)(data->InputPos.y - viewport->Pos.y + data->InputLineHeight);
         r.w = 1;
         r.h = (int)data->InputLineHeight;
         SDL_SetTextInputRect(&r);
     }
 }
 
-static ImGuiKey ImGui_ImplSDL2_KeycodeToImGuiKey(int keycode)
+// Not static to allow third-party code to use that if they want to (but undocumented)
+ImGuiKey ImGui_ImplSDL2_KeyEventToImGuiKey(SDL_Keycode keycode, SDL_Scancode scancode);
+ImGuiKey ImGui_ImplSDL2_KeyEventToImGuiKey(SDL_Keycode keycode, SDL_Scancode scancode)
 {
+    IM_UNUSED(scancode);
     switch (keycode)
     {
         case SDLK_TAB: return ImGuiKey_Tab;
@@ -286,6 +329,7 @@ static ImGuiKey ImGui_ImplSDL2_KeycodeToImGuiKey(int keycode)
         case SDLK_F24: return ImGuiKey_F24;
         case SDLK_AC_BACK: return ImGuiKey_AppBack;
         case SDLK_AC_FORWARD: return ImGuiKey_AppForward;
+        default: break;
     }
     return ImGuiKey_None;
 }
@@ -299,11 +343,15 @@ static void ImGui_ImplSDL2_UpdateKeyModifiers(SDL_Keymod sdl_key_mods)
     io.AddKeyEvent(ImGuiMod_Super, (sdl_key_mods & KMOD_GUI) != 0);
 }
 
+static ImGuiViewport* ImGui_ImplSDL2_GetViewportForWindowID(Uint32 window_id)
+{
+    return ImGui::FindViewportByPlatformHandle((void*)(intptr_t)window_id);
+}
+
 // You can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if dear imgui wants to use your inputs.
 // - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application, or clear/overwrite your copy of the mouse data.
 // - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application, or clear/overwrite your copy of the keyboard data.
 // Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
-// If you have multiple SDL events and some of them are not meant to be used by dear imgui, you may need to filter events based on their windowID field.
 bool ImGui_ImplSDL2_ProcessEvent(const SDL_Event* event)
 {
     ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();
@@ -314,13 +362,24 @@ bool ImGui_ImplSDL2_ProcessEvent(const SDL_Event* event)
     {
         case SDL_MOUSEMOTION:
         {
+            if (ImGui_ImplSDL2_GetViewportForWindowID(event->motion.windowID) == nullptr)
+                return false;
             ImVec2 mouse_pos((float)event->motion.x, (float)event->motion.y);
+            if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+            {
+                int window_x, window_y;
+                SDL_GetWindowPosition(SDL_GetWindowFromID(event->motion.windowID), &window_x, &window_y);
+                mouse_pos.x += window_x;
+                mouse_pos.y += window_y;
+            }
             io.AddMouseSourceEvent(event->motion.which == SDL_TOUCH_MOUSEID ? ImGuiMouseSource_TouchScreen : ImGuiMouseSource_Mouse);
             io.AddMousePosEvent(mouse_pos.x, mouse_pos.y);
             return true;
         }
         case SDL_MOUSEWHEEL:
         {
+            if (ImGui_ImplSDL2_GetViewportForWindowID(event->wheel.windowID) == nullptr)
+                return false;
             //IMGUI_DEBUG_LOG("wheel %.2f %.2f, precise %.2f %.2f\n", (float)event->wheel.x, (float)event->wheel.y, event->wheel.preciseX, event->wheel.preciseY);
 #if SDL_VERSION_ATLEAST(2,0,18) // If this fails to compile on Emscripten: update to latest Emscripten!
             float wheel_x = -event->wheel.preciseX;
@@ -329,7 +388,7 @@ bool ImGui_ImplSDL2_ProcessEvent(const SDL_Event* event)
             float wheel_x = -(float)event->wheel.x;
             float wheel_y = (float)event->wheel.y;
 #endif
-#ifdef __EMSCRIPTEN__
+#if defined(__EMSCRIPTEN__) && !SDL_VERSION_ATLEAST(2,31,0)
             wheel_x /= 100.0f;
 #endif
             io.AddMouseSourceEvent(event->wheel.which == SDL_TOUCH_MOUSEID ? ImGuiMouseSource_TouchScreen : ImGuiMouseSource_Mouse);
@@ -339,6 +398,8 @@ bool ImGui_ImplSDL2_ProcessEvent(const SDL_Event* event)
         case SDL_MOUSEBUTTONDOWN:
         case SDL_MOUSEBUTTONUP:
         {
+            if (ImGui_ImplSDL2_GetViewportForWindowID(event->button.windowID) == nullptr)
+                return false;
             int mouse_button = -1;
             if (event->button.button == SDL_BUTTON_LEFT) { mouse_button = 0; }
             if (event->button.button == SDL_BUTTON_RIGHT) { mouse_button = 1; }
@@ -354,20 +415,37 @@ bool ImGui_ImplSDL2_ProcessEvent(const SDL_Event* event)
         }
         case SDL_TEXTINPUT:
         {
+            if (ImGui_ImplSDL2_GetViewportForWindowID(event->text.windowID) == nullptr)
+                return false;
             io.AddInputCharactersUTF8(event->text.text);
             return true;
         }
         case SDL_KEYDOWN:
         case SDL_KEYUP:
         {
+            if (ImGui_ImplSDL2_GetViewportForWindowID(event->key.windowID) == nullptr)
+                return false;
             ImGui_ImplSDL2_UpdateKeyModifiers((SDL_Keymod)event->key.keysym.mod);
-            ImGuiKey key = ImGui_ImplSDL2_KeycodeToImGuiKey(event->key.keysym.sym);
+            ImGuiKey key = ImGui_ImplSDL2_KeyEventToImGuiKey(event->key.keysym.sym, event->key.keysym.scancode);
             io.AddKeyEvent(key, (event->type == SDL_KEYDOWN));
             io.SetKeyEventNativeData(key, event->key.keysym.sym, event->key.keysym.scancode, event->key.keysym.scancode); // To support legacy indexing (<1.87 user code). Legacy backend uses SDLK_*** as indices to IsKeyXXX() functions.
             return true;
         }
+#if SDL_HAS_DISPLAY_EVENT
+        case SDL_DISPLAYEVENT:
+        {
+            // 2.0.26 has SDL_DISPLAYEVENT_CONNECTED/SDL_DISPLAYEVENT_DISCONNECTED/SDL_DISPLAYEVENT_ORIENTATION,
+            // so change of DPI/Scaling are not reflected in this event. (SDL3 has it)
+            bd->WantUpdateMonitors = true;
+            return true;
+        }
+#endif
         case SDL_WINDOWEVENT:
         {
+            ImGuiViewport* viewport = ImGui_ImplSDL2_GetViewportForWindowID(event->window.windowID);
+            if (viewport == NULL)
+                return false;
+
             // - When capturing mouse, SDL will send a bunch of conflicting LEAVE/ENTER event on every mouse move, but the final ENTER tends to be right.
             // - However we won't get a correct LEAVE event for a captured window.
             // - In some cases, when detaching a window from main viewport SDL may send SDL_WINDOWEVENT_ENTER one frame too late,
@@ -383,8 +461,14 @@ bool ImGui_ImplSDL2_ProcessEvent(const SDL_Event* event)
                 bd->MouseLastLeaveFrame = ImGui::GetFrameCount() + 1;
             if (window_event == SDL_WINDOWEVENT_FOCUS_GAINED)
                 io.AddFocusEvent(true);
-            else if (event->window.event == SDL_WINDOWEVENT_FOCUS_LOST)
+            else if (window_event == SDL_WINDOWEVENT_FOCUS_LOST)
                 io.AddFocusEvent(false);
+            else if (window_event == SDL_WINDOWEVENT_CLOSE)
+                viewport->PlatformRequestClose = true;
+            else if (window_event == SDL_WINDOWEVENT_MOVED)
+                viewport->PlatformRequestMove = true;
+            else if (window_event == SDL_WINDOWEVENT_RESIZED)
+                viewport->PlatformRequestResize = true;
             return true;
         }
         case SDL_CONTROLLERDEVICEADDED:
@@ -397,7 +481,11 @@ bool ImGui_ImplSDL2_ProcessEvent(const SDL_Event* event)
     return false;
 }
 
-static bool ImGui_ImplSDL2_Init(SDL_Window* window, SDL_Renderer* renderer)
+#ifdef __EMSCRIPTEN__
+EM_JS(void, ImGui_ImplSDL2_EmscriptenOpenURL, (char const* url), { url = url ? UTF8ToString(url) : null; if (url) window.open(url, '_blank'); });
+#endif
+
+static bool ImGui_ImplSDL2_Init(SDL_Window* window, SDL_Renderer* renderer, void* sdl_gl_context)
 {
     ImGuiIO& io = ImGui::GetIO();
     IMGUI_CHECKVERSION();
@@ -418,17 +506,35 @@ static bool ImGui_ImplSDL2_Init(SDL_Window* window, SDL_Renderer* renderer)
     ImGui_ImplSDL2_Data* bd = IM_NEW(ImGui_ImplSDL2_Data)();
     io.BackendPlatformUserData = (void*)bd;
     io.BackendPlatformName = "imgui_impl_sdl2";
-    io.BackendFlags |= ImGuiBackendFlags_HasMouseCursors;       // We can honor GetMouseCursor() values (optional)
-    io.BackendFlags |= ImGuiBackendFlags_HasSetMousePos;        // We can honor io.WantSetMousePos requests (optional, rarely used)
+    io.BackendFlags |= ImGuiBackendFlags_HasMouseCursors;           // We can honor GetMouseCursor() values (optional)
+    io.BackendFlags |= ImGuiBackendFlags_HasSetMousePos;            // We can honor io.WantSetMousePos requests (optional, rarely used)
+    if (mouse_can_use_global_state)
+        io.BackendFlags |= ImGuiBackendFlags_PlatformHasViewports;  // We can create multi-viewports on the Platform side (optional)
 
     bd->Window = window;
+    bd->WindowID = SDL_GetWindowID(window);
     bd->Renderer = renderer;
-    bd->MouseCanUseGlobalState = mouse_can_use_global_state;
 
-    io.SetClipboardTextFn = ImGui_ImplSDL2_SetClipboardText;
-    io.GetClipboardTextFn = ImGui_ImplSDL2_GetClipboardText;
-    io.ClipboardUserData = nullptr;
-    io.SetPlatformImeDataFn = ImGui_ImplSDL2_SetPlatformImeData;
+    // SDL on Linux/OSX doesn't report events for unfocused windows (see https://github.com/ocornut/imgui/issues/4960)
+    // We will use 'MouseCanReportHoveredViewport' to set 'ImGuiBackendFlags_HasMouseHoveredViewport' dynamically each frame.
+    bd->MouseCanUseGlobalState = mouse_can_use_global_state;
+#ifndef __APPLE__
+    bd->MouseCanReportHoveredViewport = bd->MouseCanUseGlobalState;
+#else
+    bd->MouseCanReportHoveredViewport = false;
+#endif
+
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    platform_io.Platform_SetClipboardTextFn = ImGui_ImplSDL2_SetClipboardText;
+    platform_io.Platform_GetClipboardTextFn = ImGui_ImplSDL2_GetClipboardText;
+    platform_io.Platform_ClipboardUserData = nullptr;
+    platform_io.Platform_SetImeDataFn = ImGui_ImplSDL2_PlatformSetImeData;
+#ifdef __EMSCRIPTEN__
+    platform_io.Platform_OpenInShellFn = [](ImGuiContext*, const char* url) { ImGui_ImplSDL2_EmscriptenOpenURL(url); return true; };
+#endif
+
+    // Update monitor a first time during init
+    ImGui_ImplSDL2_UpdateMonitors();
 
     // Gamepad handling
     bd->GamepadMode = ImGui_ImplSDL2_GamepadMode_AutoFirst;
@@ -448,6 +554,7 @@ static bool ImGui_ImplSDL2_Init(SDL_Window* window, SDL_Renderer* renderer)
     // Set platform dependent data in viewport
     // Our mouse update function expect PlatformHandle to be filled for the main viewport
     ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+    main_viewport->PlatformHandle = (void*)(intptr_t)bd->WindowID;
     main_viewport->PlatformHandleRaw = nullptr;
     SDL_SysWMinfo info;
     SDL_VERSION(&info.version);
@@ -481,13 +588,17 @@ static bool ImGui_ImplSDL2_Init(SDL_Window* window, SDL_Renderer* renderer)
     SDL_SetHint(SDL_HINT_MOUSE_AUTO_CAPTURE, "0");
 #endif
 
+    // We need SDL_CaptureMouse(), SDL_GetGlobalMouseState() from SDL 2.0.4+ to support multiple viewports.
+    // We left the call to ImGui_ImplSDL2_InitMultiViewportSupport() outside of #ifdef to avoid unused-function warnings.
+    if (io.BackendFlags & ImGuiBackendFlags_PlatformHasViewports)
+        ImGui_ImplSDL2_InitMultiViewportSupport(window, sdl_gl_context);
+
     return true;
 }
 
 bool ImGui_ImplSDL2_InitForOpenGL(SDL_Window* window, void* sdl_gl_context)
 {
-    IM_UNUSED(sdl_gl_context); // Viewport branch will need this.
-    return ImGui_ImplSDL2_Init(window, nullptr);
+    return ImGui_ImplSDL2_Init(window, nullptr, sdl_gl_context);
 }
 
 bool ImGui_ImplSDL2_InitForVulkan(SDL_Window* window)
@@ -495,7 +606,11 @@ bool ImGui_ImplSDL2_InitForVulkan(SDL_Window* window)
 #if !SDL_HAS_VULKAN
     IM_ASSERT(0 && "Unsupported");
 #endif
-    return ImGui_ImplSDL2_Init(window, nullptr);
+    if (!ImGui_ImplSDL2_Init(window, nullptr, nullptr))
+        return false;
+    ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();
+    bd->UseVulkan = true;
+    return true;
 }
 
 bool ImGui_ImplSDL2_InitForD3D(SDL_Window* window)
@@ -503,22 +618,22 @@ bool ImGui_ImplSDL2_InitForD3D(SDL_Window* window)
 #if !defined(_WIN32)
     IM_ASSERT(0 && "Unsupported");
 #endif
-    return ImGui_ImplSDL2_Init(window, nullptr);
+    return ImGui_ImplSDL2_Init(window, nullptr, nullptr);
 }
 
 bool ImGui_ImplSDL2_InitForMetal(SDL_Window* window)
 {
-    return ImGui_ImplSDL2_Init(window, nullptr);
+    return ImGui_ImplSDL2_Init(window, nullptr, nullptr);
 }
 
 bool ImGui_ImplSDL2_InitForSDLRenderer(SDL_Window* window, SDL_Renderer* renderer)
 {
-    return ImGui_ImplSDL2_Init(window, renderer);
+    return ImGui_ImplSDL2_Init(window, renderer, nullptr);
 }
 
 bool ImGui_ImplSDL2_InitForOther(SDL_Window* window)
 {
-    return ImGui_ImplSDL2_Init(window, nullptr);
+    return ImGui_ImplSDL2_Init(window, nullptr, nullptr);
 }
 
 static void ImGui_ImplSDL2_CloseGamepads();
@@ -529,6 +644,8 @@ void ImGui_ImplSDL2_Shutdown()
     IM_ASSERT(bd != nullptr && "No platform backend to shutdown, or already shutdown?");
     ImGuiIO& io = ImGui::GetIO();
 
+    ImGui_ImplSDL2_ShutdownMultiViewportSupport();
+
     if (bd->ClipboardTextData)
         SDL_free(bd->ClipboardTextData);
     for (ImGuiMouseCursor cursor_n = 0; cursor_n < ImGuiMouseCursor_COUNT; cursor_n++)
@@ -537,10 +654,11 @@ void ImGui_ImplSDL2_Shutdown()
 
     io.BackendPlatformName = nullptr;
     io.BackendPlatformUserData = nullptr;
-    io.BackendFlags &= ~(ImGuiBackendFlags_HasMouseCursors | ImGuiBackendFlags_HasSetMousePos | ImGuiBackendFlags_HasGamepad);
+    io.BackendFlags &= ~(ImGuiBackendFlags_HasMouseCursors | ImGuiBackendFlags_HasSetMousePos | ImGuiBackendFlags_HasGamepad | ImGuiBackendFlags_PlatformHasViewports | ImGuiBackendFlags_HasMouseHoveredViewport);
     IM_DELETE(bd);
 }
 
+// This code is incredibly messy because some of the functions we need for full viewport support are not available in SDL < 2.0.4.
 static void ImGui_ImplSDL2_UpdateMouseData()
 {
     ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();
@@ -551,25 +669,56 @@ static void ImGui_ImplSDL2_UpdateMouseData()
     // SDL_CaptureMouse() let the OS know e.g. that our imgui drag outside the SDL window boundaries shouldn't e.g. trigger other operations outside
     SDL_CaptureMouse((bd->MouseButtonsDown != 0) ? SDL_TRUE : SDL_FALSE);
     SDL_Window* focused_window = SDL_GetKeyboardFocus();
-    const bool is_app_focused = (bd->Window == focused_window);
+    const bool is_app_focused = (focused_window && (bd->Window == focused_window || ImGui_ImplSDL2_GetViewportForWindowID(SDL_GetWindowID(focused_window)) != NULL));
 #else
+    SDL_Window* focused_window = bd->Window;
     const bool is_app_focused = (SDL_GetWindowFlags(bd->Window) & SDL_WINDOW_INPUT_FOCUS) != 0; // SDL 2.0.3 and non-windowed systems: single-viewport only
 #endif
+
     if (is_app_focused)
     {
-        // (Optional) Set OS mouse position from Dear ImGui if requested (rarely used, only when ImGuiConfigFlags_NavEnableSetMousePos is enabled by user)
+        // (Optional) Set OS mouse position from Dear ImGui if requested (rarely used, only when io.ConfigNavMoveSetMousePos is enabled by user)
         if (io.WantSetMousePos)
-            SDL_WarpMouseInWindow(bd->Window, (int)io.MousePos.x, (int)io.MousePos.y);
+        {
+#if SDL_HAS_CAPTURE_AND_GLOBAL_MOUSE
+            if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+                SDL_WarpMouseGlobal((int)io.MousePos.x, (int)io.MousePos.y);
+            else
+#endif
+                SDL_WarpMouseInWindow(bd->Window, (int)io.MousePos.x, (int)io.MousePos.y);
+        }
 
         // (Optional) Fallback to provide mouse position when focused (SDL_MOUSEMOTION already provides this when hovered or captured)
         if (bd->MouseCanUseGlobalState && bd->MouseButtonsDown == 0)
         {
-            int window_x, window_y, mouse_x_global, mouse_y_global;
-            SDL_GetGlobalMouseState(&mouse_x_global, &mouse_y_global);
-            SDL_GetWindowPosition(bd->Window, &window_x, &window_y);
-            io.AddMousePosEvent((float)(mouse_x_global - window_x), (float)(mouse_y_global - window_y));
+            // Single-viewport mode: mouse position in client window coordinates (io.MousePos is (0,0) when the mouse is on the upper-left corner of the app window)
+            // Multi-viewport mode: mouse position in OS absolute coordinates (io.MousePos is (0,0) when the mouse is on the upper-left of the primary monitor)
+            int mouse_x, mouse_y, window_x, window_y;
+            SDL_GetGlobalMouseState(&mouse_x, &mouse_y);
+            if (!(io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable))
+            {
+                SDL_GetWindowPosition(focused_window, &window_x, &window_y);
+                mouse_x -= window_x;
+                mouse_y -= window_y;
+            }
+            io.AddMousePosEvent((float)mouse_x, (float)mouse_y);
         }
     }
+
+    // (Optional) When using multiple viewports: call io.AddMouseViewportEvent() with the viewport the OS mouse cursor is hovering.
+    // If ImGuiBackendFlags_HasMouseHoveredViewport is not set by the backend, Dear imGui will ignore this field and infer the information using its flawed heuristic.
+    // - [!] SDL backend does NOT correctly ignore viewports with the _NoInputs flag.
+    //       Some backend are not able to handle that correctly. If a backend report an hovered viewport that has the _NoInputs flag (e.g. when dragging a window
+    //       for docking, the viewport has the _NoInputs flag in order to allow us to find the viewport under), then Dear ImGui is forced to ignore the value reported
+    //       by the backend, and use its flawed heuristic to guess the viewport behind.
+    // - [X] SDL backend correctly reports this regardless of another viewport behind focused and dragged from (we need this to find a useful drag and drop target).
+    if (io.BackendFlags & ImGuiBackendFlags_HasMouseHoveredViewport)
+    {
+        ImGuiID mouse_viewport_id = 0;
+        if (ImGuiViewport* mouse_viewport = ImGui_ImplSDL2_GetViewportForWindowID(bd->MouseWindowID))
+            mouse_viewport_id = mouse_viewport->ID;
+        io.AddMouseViewportEvent(mouse_viewport_id);
+    }
 }
 
 static void ImGui_ImplSDL2_UpdateMouseCursor()
@@ -703,6 +852,43 @@ static void ImGui_ImplSDL2_UpdateGamepads()
     ImGui_ImplSDL2_UpdateGamepadAnalog(bd, io, ImGuiKey_GamepadRStickDown,  SDL_CONTROLLER_AXIS_RIGHTY, +thumb_dead_zone, +32767);
 }
 
+// FIXME: Note that doesn't update with DPI/Scaling change only as SDL2 doesn't have an event for it (SDL3 has).
+static void ImGui_ImplSDL2_UpdateMonitors()
+{
+    ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    platform_io.Monitors.resize(0);
+    bd->WantUpdateMonitors = false;
+    int display_count = SDL_GetNumVideoDisplays();
+    for (int n = 0; n < display_count; n++)
+    {
+        // Warning: the validity of monitor DPI information on Windows depends on the application DPI awareness settings, which generally needs to be set in the manifest or at runtime.
+        ImGuiPlatformMonitor monitor;
+        SDL_Rect r;
+        SDL_GetDisplayBounds(n, &r);
+        monitor.MainPos = monitor.WorkPos = ImVec2((float)r.x, (float)r.y);
+        monitor.MainSize = monitor.WorkSize = ImVec2((float)r.w, (float)r.h);
+#if SDL_HAS_USABLE_DISPLAY_BOUNDS
+        SDL_GetDisplayUsableBounds(n, &r);
+        monitor.WorkPos = ImVec2((float)r.x, (float)r.y);
+        monitor.WorkSize = ImVec2((float)r.w, (float)r.h);
+#endif
+#if SDL_HAS_PER_MONITOR_DPI
+        // FIXME-VIEWPORT: On MacOS SDL reports actual monitor DPI scale, ignoring OS configuration. We may want to set
+        //  DpiScale to cocoa_window.backingScaleFactor here.
+        float dpi = 0.0f;
+        if (!SDL_GetDisplayDPI(n, &dpi, nullptr, nullptr))
+        {
+            if (dpi <= 0.0f)
+                continue; // Some accessibility applications are declaring virtual monitors with a DPI of 0, see #7902.
+            monitor.DpiScale = dpi / 96.0f;
+        }
+#endif
+        monitor.PlatformHandle = (void*)(intptr_t)n;
+        platform_io.Monitors.push_back(monitor);
+    }
+}
+
 void ImGui_ImplSDL2_NewFrame()
 {
     ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();
@@ -717,12 +903,20 @@ void ImGui_ImplSDL2_NewFrame()
         w = h = 0;
     if (bd->Renderer != nullptr)
         SDL_GetRendererOutputSize(bd->Renderer, &display_w, &display_h);
+#if SDL_HAS_VULKAN
+    else if (SDL_GetWindowFlags(bd->Window) & SDL_WINDOW_VULKAN)
+        SDL_Vulkan_GetDrawableSize(bd->Window, &display_w, &display_h);
+#endif
     else
         SDL_GL_GetDrawableSize(bd->Window, &display_w, &display_h);
     io.DisplaySize = ImVec2((float)w, (float)h);
     if (w > 0 && h > 0)
         io.DisplayFramebufferScale = ImVec2((float)display_w / w, (float)display_h / h);
 
+    // Update monitors
+    if (bd->WantUpdateMonitors)
+        ImGui_ImplSDL2_UpdateMonitors();
+
     // Setup time step (we don't use SDL_GetTicks() because it is using millisecond resolution)
     // (Accept SDL_GetPerformanceCounter() not returning a monotonically increasing value. Happens in VMs and Emscripten, see #6189, #6114, #3644)
     static Uint64 frequency = SDL_GetPerformanceFrequency();
@@ -739,6 +933,13 @@ void ImGui_ImplSDL2_NewFrame()
         io.AddMousePosEvent(-FLT_MAX, -FLT_MAX);
     }
 
+    // Our io.AddMouseViewportEvent() calls will only be valid when not capturing.
+    // Technically speaking testing for 'bd->MouseButtonsDown == 0' would be more rigorous, but testing for payload reduces noise and potential side-effects.
+    if (bd->MouseCanReportHoveredViewport && ImGui::GetDragDropPayload() == nullptr)
+        io.BackendFlags |= ImGuiBackendFlags_HasMouseHoveredViewport;
+    else
+        io.BackendFlags &= ~ImGuiBackendFlags_HasMouseHoveredViewport;
+
     ImGui_ImplSDL2_UpdateMouseData();
     ImGui_ImplSDL2_UpdateMouseCursor();
 
@@ -746,6 +947,256 @@ void ImGui_ImplSDL2_NewFrame()
     ImGui_ImplSDL2_UpdateGamepads();
 }
 
+//--------------------------------------------------------------------------------------------------------
+// MULTI-VIEWPORT / PLATFORM INTERFACE SUPPORT
+// This is an _advanced_ and _optional_ feature, allowing the backend to create and handle multiple viewports simultaneously.
+// If you are new to dear imgui or creating a new binding for dear imgui, it is recommended that you completely ignore this section first..
+//--------------------------------------------------------------------------------------------------------
+
+// Helper structure we store in the void* RendererUserData field of each ImGuiViewport to easily retrieve our backend data.
+struct ImGui_ImplSDL2_ViewportData
+{
+    SDL_Window*     Window;
+    Uint32          WindowID;
+    bool            WindowOwned;
+    SDL_GLContext   GLContext;
+
+    ImGui_ImplSDL2_ViewportData() { Window = nullptr; WindowID = 0; WindowOwned = false; GLContext = nullptr; }
+    ~ImGui_ImplSDL2_ViewportData() { IM_ASSERT(Window == nullptr && GLContext == nullptr); }
+};
+
+static void ImGui_ImplSDL2_CreateWindow(ImGuiViewport* viewport)
+{
+    ImGui_ImplSDL2_Data* bd = ImGui_ImplSDL2_GetBackendData();
+    ImGui_ImplSDL2_ViewportData* vd = IM_NEW(ImGui_ImplSDL2_ViewportData)();
+    viewport->PlatformUserData = vd;
+
+    ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+    ImGui_ImplSDL2_ViewportData* main_viewport_data = (ImGui_ImplSDL2_ViewportData*)main_viewport->PlatformUserData;
+
+    // Share GL resources with main context
+    bool use_opengl = (main_viewport_data->GLContext != nullptr);
+    SDL_GLContext backup_context = nullptr;
+    if (use_opengl)
+    {
+        backup_context = SDL_GL_GetCurrentContext();
+        SDL_GL_SetAttribute(SDL_GL_SHARE_WITH_CURRENT_CONTEXT, 1);
+        SDL_GL_MakeCurrent(main_viewport_data->Window, main_viewport_data->GLContext);
+    }
+
+    Uint32 sdl_flags = 0;
+    sdl_flags |= use_opengl ? SDL_WINDOW_OPENGL : (bd->UseVulkan ? SDL_WINDOW_VULKAN : 0);
+    sdl_flags |= SDL_GetWindowFlags(bd->Window) & SDL_WINDOW_ALLOW_HIGHDPI;
+    sdl_flags |= SDL_WINDOW_HIDDEN;
+    sdl_flags |= (viewport->Flags & ImGuiViewportFlags_NoDecoration) ? SDL_WINDOW_BORDERLESS : 0;
+    sdl_flags |= (viewport->Flags & ImGuiViewportFlags_NoDecoration) ? 0 : SDL_WINDOW_RESIZABLE;
+#if !defined(_WIN32)
+    // See SDL hack in ImGui_ImplSDL2_ShowWindow().
+    sdl_flags |= (viewport->Flags & ImGuiViewportFlags_NoTaskBarIcon) ? SDL_WINDOW_SKIP_TASKBAR : 0;
+#endif
+#if SDL_HAS_ALWAYS_ON_TOP
+    sdl_flags |= (viewport->Flags & ImGuiViewportFlags_TopMost) ? SDL_WINDOW_ALWAYS_ON_TOP : 0;
+#endif
+    vd->Window = SDL_CreateWindow("No Title Yet", (int)viewport->Pos.x, (int)viewport->Pos.y, (int)viewport->Size.x, (int)viewport->Size.y, sdl_flags);
+    vd->WindowOwned = true;
+    if (use_opengl)
+    {
+        vd->GLContext = SDL_GL_CreateContext(vd->Window);
+        SDL_GL_SetSwapInterval(0);
+    }
+    if (use_opengl && backup_context)
+        SDL_GL_MakeCurrent(vd->Window, backup_context);
+
+    viewport->PlatformHandle = (void*)(intptr_t)SDL_GetWindowID(vd->Window);
+    viewport->PlatformHandleRaw = nullptr;
+    SDL_SysWMinfo info;
+    SDL_VERSION(&info.version);
+    if (SDL_GetWindowWMInfo(vd->Window, &info))
+    {
+#if defined(SDL_VIDEO_DRIVER_WINDOWS)
+        viewport->PlatformHandleRaw = info.info.win.window;
+#elif defined(__APPLE__) && defined(SDL_VIDEO_DRIVER_COCOA)
+        viewport->PlatformHandleRaw = (void*)info.info.cocoa.window;
+#endif
+    }
+}
+
+static void ImGui_ImplSDL2_DestroyWindow(ImGuiViewport* viewport)
+{
+    if (ImGui_ImplSDL2_ViewportData* vd = (ImGui_ImplSDL2_ViewportData*)viewport->PlatformUserData)
+    {
+        if (vd->GLContext && vd->WindowOwned)
+            SDL_GL_DeleteContext(vd->GLContext);
+        if (vd->Window && vd->WindowOwned)
+            SDL_DestroyWindow(vd->Window);
+        vd->GLContext = nullptr;
+        vd->Window = nullptr;
+        IM_DELETE(vd);
+    }
+    viewport->PlatformUserData = viewport->PlatformHandle = nullptr;
+}
+
+static void ImGui_ImplSDL2_ShowWindow(ImGuiViewport* viewport)
+{
+    ImGui_ImplSDL2_ViewportData* vd = (ImGui_ImplSDL2_ViewportData*)viewport->PlatformUserData;
+#if defined(_WIN32) && !(defined(WINAPI_FAMILY) && (WINAPI_FAMILY == WINAPI_FAMILY_APP || WINAPI_FAMILY == WINAPI_FAMILY_GAMES))
+    HWND hwnd = (HWND)viewport->PlatformHandleRaw;
+
+    // SDL hack: Hide icon from task bar
+    // Note: SDL 2.0.6+ has a SDL_WINDOW_SKIP_TASKBAR flag which is supported under Windows but the way it create the window breaks our seamless transition.
+    if (viewport->Flags & ImGuiViewportFlags_NoTaskBarIcon)
+    {
+        LONG ex_style = ::GetWindowLong(hwnd, GWL_EXSTYLE);
+        ex_style &= ~WS_EX_APPWINDOW;
+        ex_style |= WS_EX_TOOLWINDOW;
+        ::SetWindowLong(hwnd, GWL_EXSTYLE, ex_style);
+    }
+#endif
+
+#if SDL_HAS_SHOW_WINDOW_ACTIVATION_HINT
+    SDL_SetHint(SDL_HINT_WINDOW_NO_ACTIVATION_WHEN_SHOWN, (viewport->Flags & ImGuiViewportFlags_NoFocusOnAppearing) ? "1" : "0");
+#elif defined(_WIN32)
+    // SDL hack: SDL always activate/focus windows :/
+    if (viewport->Flags & ImGuiViewportFlags_NoFocusOnAppearing)
+    {
+        ::ShowWindow(hwnd, SW_SHOWNA);
+        return;
+    }
+#endif
+    SDL_ShowWindow(vd->Window);
+}
+
+static ImVec2 ImGui_ImplSDL2_GetWindowPos(ImGuiViewport* viewport)
+{
+    ImGui_ImplSDL2_ViewportData* vd = (ImGui_ImplSDL2_ViewportData*)viewport->PlatformUserData;
+    int x = 0, y = 0;
+    SDL_GetWindowPosition(vd->Window, &x, &y);
+    return ImVec2((float)x, (float)y);
+}
+
+static void ImGui_ImplSDL2_SetWindowPos(ImGuiViewport* viewport, ImVec2 pos)
+{
+    ImGui_ImplSDL2_ViewportData* vd = (ImGui_ImplSDL2_ViewportData*)viewport->PlatformUserData;
+    SDL_SetWindowPosition(vd->Window, (int)pos.x, (int)pos.y);
+}
+
+static ImVec2 ImGui_ImplSDL2_GetWindowSize(ImGuiViewport* viewport)
+{
+    ImGui_ImplSDL2_ViewportData* vd = (ImGui_ImplSDL2_ViewportData*)viewport->PlatformUserData;
+    int w = 0, h = 0;
+    SDL_GetWindowSize(vd->Window, &w, &h);
+    return ImVec2((float)w, (float)h);
+}
+
+static void ImGui_ImplSDL2_SetWindowSize(ImGuiViewport* viewport, ImVec2 size)
+{
+    ImGui_ImplSDL2_ViewportData* vd = (ImGui_ImplSDL2_ViewportData*)viewport->PlatformUserData;
+    SDL_SetWindowSize(vd->Window, (int)size.x, (int)size.y);
+}
+
+static void ImGui_ImplSDL2_SetWindowTitle(ImGuiViewport* viewport, const char* title)
+{
+    ImGui_ImplSDL2_ViewportData* vd = (ImGui_ImplSDL2_ViewportData*)viewport->PlatformUserData;
+    SDL_SetWindowTitle(vd->Window, title);
+}
+
+#if SDL_HAS_WINDOW_ALPHA
+static void ImGui_ImplSDL2_SetWindowAlpha(ImGuiViewport* viewport, float alpha)
+{
+    ImGui_ImplSDL2_ViewportData* vd = (ImGui_ImplSDL2_ViewportData*)viewport->PlatformUserData;
+    SDL_SetWindowOpacity(vd->Window, alpha);
+}
+#endif
+
+static void ImGui_ImplSDL2_SetWindowFocus(ImGuiViewport* viewport)
+{
+    ImGui_ImplSDL2_ViewportData* vd = (ImGui_ImplSDL2_ViewportData*)viewport->PlatformUserData;
+    SDL_RaiseWindow(vd->Window);
+}
+
+static bool ImGui_ImplSDL2_GetWindowFocus(ImGuiViewport* viewport)
+{
+    ImGui_ImplSDL2_ViewportData* vd = (ImGui_ImplSDL2_ViewportData*)viewport->PlatformUserData;
+    return (SDL_GetWindowFlags(vd->Window) & SDL_WINDOW_INPUT_FOCUS) != 0;
+}
+
+static bool ImGui_ImplSDL2_GetWindowMinimized(ImGuiViewport* viewport)
+{
+    ImGui_ImplSDL2_ViewportData* vd = (ImGui_ImplSDL2_ViewportData*)viewport->PlatformUserData;
+    return (SDL_GetWindowFlags(vd->Window) & SDL_WINDOW_MINIMIZED) != 0;
+}
+
+static void ImGui_ImplSDL2_RenderWindow(ImGuiViewport* viewport, void*)
+{
+    ImGui_ImplSDL2_ViewportData* vd = (ImGui_ImplSDL2_ViewportData*)viewport->PlatformUserData;
+    if (vd->GLContext)
+        SDL_GL_MakeCurrent(vd->Window, vd->GLContext);
+}
+
+static void ImGui_ImplSDL2_SwapBuffers(ImGuiViewport* viewport, void*)
+{
+    ImGui_ImplSDL2_ViewportData* vd = (ImGui_ImplSDL2_ViewportData*)viewport->PlatformUserData;
+    if (vd->GLContext)
+    {
+        SDL_GL_MakeCurrent(vd->Window, vd->GLContext);
+        SDL_GL_SwapWindow(vd->Window);
+    }
+}
+
+// Vulkan support (the Vulkan renderer needs to call a platform-side support function to create the surface)
+// SDL is graceful enough to _not_ need <vulkan/vulkan.h> so we can safely include this.
+#if SDL_HAS_VULKAN
+#include <SDL_vulkan.h>
+static int ImGui_ImplSDL2_CreateVkSurface(ImGuiViewport* viewport, ImU64 vk_instance, const void* vk_allocator, ImU64* out_vk_surface)
+{
+    ImGui_ImplSDL2_ViewportData* vd = (ImGui_ImplSDL2_ViewportData*)viewport->PlatformUserData;
+    (void)vk_allocator;
+    SDL_bool ret = SDL_Vulkan_CreateSurface(vd->Window, (VkInstance)vk_instance, (VkSurfaceKHR*)out_vk_surface);
+    return ret ? 0 : 1; // ret ? VK_SUCCESS : VK_NOT_READY
+}
+#endif // SDL_HAS_VULKAN
+
+static void ImGui_ImplSDL2_InitMultiViewportSupport(SDL_Window* window, void* sdl_gl_context)
+{
+    // Register platform interface (will be coupled with a renderer interface)
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    platform_io.Platform_CreateWindow = ImGui_ImplSDL2_CreateWindow;
+    platform_io.Platform_DestroyWindow = ImGui_ImplSDL2_DestroyWindow;
+    platform_io.Platform_ShowWindow = ImGui_ImplSDL2_ShowWindow;
+    platform_io.Platform_SetWindowPos = ImGui_ImplSDL2_SetWindowPos;
+    platform_io.Platform_GetWindowPos = ImGui_ImplSDL2_GetWindowPos;
+    platform_io.Platform_SetWindowSize = ImGui_ImplSDL2_SetWindowSize;
+    platform_io.Platform_GetWindowSize = ImGui_ImplSDL2_GetWindowSize;
+    platform_io.Platform_SetWindowFocus = ImGui_ImplSDL2_SetWindowFocus;
+    platform_io.Platform_GetWindowFocus = ImGui_ImplSDL2_GetWindowFocus;
+    platform_io.Platform_GetWindowMinimized = ImGui_ImplSDL2_GetWindowMinimized;
+    platform_io.Platform_SetWindowTitle = ImGui_ImplSDL2_SetWindowTitle;
+    platform_io.Platform_RenderWindow = ImGui_ImplSDL2_RenderWindow;
+    platform_io.Platform_SwapBuffers = ImGui_ImplSDL2_SwapBuffers;
+#if SDL_HAS_WINDOW_ALPHA
+    platform_io.Platform_SetWindowAlpha = ImGui_ImplSDL2_SetWindowAlpha;
+#endif
+#if SDL_HAS_VULKAN
+    platform_io.Platform_CreateVkSurface = ImGui_ImplSDL2_CreateVkSurface;
+#endif
+
+    // Register main window handle (which is owned by the main application, not by us)
+    // This is mostly for simplicity and consistency, so that our code (e.g. mouse handling etc.) can use same logic for main and secondary viewports.
+    ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+    ImGui_ImplSDL2_ViewportData* vd = IM_NEW(ImGui_ImplSDL2_ViewportData)();
+    vd->Window = window;
+    vd->WindowID = SDL_GetWindowID(window);
+    vd->WindowOwned = false;
+    vd->GLContext = sdl_gl_context;
+    main_viewport->PlatformUserData = vd;
+    main_viewport->PlatformHandle = (void*)(intptr_t)vd->WindowID;
+}
+
+static void ImGui_ImplSDL2_ShutdownMultiViewportSupport()
+{
+    ImGui::DestroyPlatformWindows();
+}
+
 //-----------------------------------------------------------------------------
 
 #if defined(__clang__)

backends/imgui_impl_sdl2.h

@@ -5,10 +5,14 @@
 // Implemented features:
 //  [X] Platform: Clipboard support.
 //  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen.
-//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy SDL_SCANCODE_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy SDL_SCANCODE_* values are obsolete since 1.87 and not supported since 1.91.5]
 //  [X] Platform: Gamepad support. Enabled with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
-//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+//  [X] Platform: Mouse cursor shape and visibility (ImGuiBackendFlags_HasMouseCursors). Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
 //  [X] Platform: Basic IME support. App needs to call 'SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1");' before SDL_CreateWindow()!.
+//  [X] Platform: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
+// Missing features or Issues:
+//  [ ] Platform: Multi-viewport: Minimized windows seems to break mouse wheel events (at least under Windows).
+//  [ ] Platform: Multi-viewport: ParentViewportID not honored, and so io.ConfigViewportsNoDefaultParent has no effect (minor).
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -27,6 +31,7 @@ struct SDL_Renderer;
 struct _SDL_GameController;
 typedef union SDL_Event SDL_Event;
 
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
 IMGUI_IMPL_API bool     ImGui_ImplSDL2_InitForOpenGL(SDL_Window* window, void* sdl_gl_context);
 IMGUI_IMPL_API bool     ImGui_ImplSDL2_InitForVulkan(SDL_Window* window);
 IMGUI_IMPL_API bool     ImGui_ImplSDL2_InitForD3D(SDL_Window* window);
@@ -40,6 +45,6 @@ IMGUI_IMPL_API bool     ImGui_ImplSDL2_ProcessEvent(const SDL_Event* event);
 // Gamepad selection automatically starts in AutoFirst mode, picking first available SDL_Gamepad. You may override this.
 // When using manual mode, caller is responsible for opening/closing gamepad.
 enum ImGui_ImplSDL2_GamepadMode { ImGui_ImplSDL2_GamepadMode_AutoFirst, ImGui_ImplSDL2_GamepadMode_AutoAll, ImGui_ImplSDL2_GamepadMode_Manual };
-IMGUI_IMPL_API void     ImGui_ImplSDL2_SetGamepadMode(ImGui_ImplSDL2_GamepadMode mode, struct _SDL_GameController** manual_gamepads_array = NULL, int manual_gamepads_count = -1);
+IMGUI_IMPL_API void     ImGui_ImplSDL2_SetGamepadMode(ImGui_ImplSDL2_GamepadMode mode, struct _SDL_GameController** manual_gamepads_array = nullptr, int manual_gamepads_count = -1);
 
 #endif // #ifndef IMGUI_DISABLE

backends/imgui_impl_sdl3.cpp

@@ -1,16 +1,19 @@
 // dear imgui: Platform Backend for SDL3 (*EXPERIMENTAL*)
 // This needs to be used along with a Renderer (e.g. DirectX11, OpenGL3, Vulkan..)
 // (Info: SDL3 is a cross-platform general purpose library for handling windows, inputs, graphics context creation, etc.)
-// (IMPORTANT: SDL 3.0.0 is NOT YET RELEASED. IT IS POSSIBLE THAT ITS SPECS/API WILL CHANGE BEFORE RELEASE)
+
+// (**IMPORTANT: SDL 3.0.0 is NOT YET RELEASED AND CURRENTLY HAS A FAST CHANGING API. THIS CODE BREAKS OFTEN AS SDL3 CHANGES.**)
 
 // Implemented features:
 //  [X] Platform: Clipboard support.
 //  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen.
-//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy SDL_SCANCODE_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy SDL_SCANCODE_* values are obsolete since 1.87 and not supported since 1.91.5]
 //  [X] Platform: Gamepad support. Enabled with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
-//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
-// Missing features:
-//  [ ] Platform: IME SUPPORT IS BROKEN IN SDL3 BECAUSE INPUTS GETS SENT TO BOTH APP AND IME + app needs to call 'SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1");' before SDL_CreateWindow()!.
+//  [X] Platform: Mouse cursor shape and visibility (ImGuiBackendFlags_HasMouseCursors). Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+//  [x] Platform: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable' -> the OS animation effect when window gets created/destroyed is problematic. SDL2 backend doesn't have issue.
+// Missing features or Issues:
+//  [ ] Platform: Multi-viewport: Minimized windows seems to break mouse wheel events (at least under Windows).
+//  [x] Platform: IME support. Position somehow broken in SDL3 + app needs to call 'SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1");' before SDL_CreateWindow()!.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -22,6 +25,25 @@
 
 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
+//  2024-XX-XX: Platform: Added support for multiple windows via the ImGuiPlatformIO interface.
+//  2024-09-11: (Docking) Added support for viewport->ParentViewportId field to support parenting at OS level. (#7973)
+//  2024-10-24: Emscripten: SDL_EVENT_MOUSE_WHEEL event doesn't require dividing by 100.0f on Emscripten.
+//  2024-09-03: Update for SDL3 api changes: SDL_GetGamepads() memory ownership revert. (#7918, #7898, #7807)
+//  2024-08-22: moved some OS/backend related function pointers from ImGuiIO to ImGuiPlatformIO:
+//               - io.GetClipboardTextFn    -> platform_io.Platform_GetClipboardTextFn
+//               - io.SetClipboardTextFn    -> platform_io.Platform_SetClipboardTextFn
+//               - io.PlatformSetImeDataFn  -> platform_io.Platform_SetImeDataFn
+//  2024-08-19: Storing SDL_WindowID inside ImGuiViewport::PlatformHandle instead of SDL_Window*.
+//  2024-08-19: ImGui_ImplSDL3_ProcessEvent() now ignores events intended for other SDL windows. (#7853)
+//  2024-07-22: Update for SDL3 api changes: SDL_GetGamepads() memory ownership change. (#7807)
+//  2024-07-18: Update for SDL3 api changes: SDL_GetClipboardText() memory ownership change. (#7801)
+//  2024-07-15: Update for SDL3 api changes: SDL_GetProperty() change to SDL_GetPointerProperty(). (#7794)
+//  2024-07-02: Update for SDL3 api changes: SDLK_x renames and SDLK_KP_x removals (#7761, #7762).
+//  2024-07-01: Update for SDL3 api changes: SDL_SetTextInputRect() changed to SDL_SetTextInputArea().
+//  2024-06-26: Update for SDL3 api changes: SDL_StartTextInput()/SDL_StopTextInput()/SDL_SetTextInputRect() functions signatures.
+//  2024-06-24: Update for SDL3 api changes: SDL_EVENT_KEY_DOWN/SDL_EVENT_KEY_UP contents.
+//  2024-06-03; Update for SDL3 api changes: SDL_SYSTEM_CURSOR_ renames.
+//  2024-05-15: Update for SDL3 api changes: SDLK_ renames.
 //  2024-04-15: Inputs: Re-enable calling SDL_StartTextInput()/SDL_StopTextInput() as SDL3 no longer enables it by default and should play nicer with IME.
 //  2024-02-13: Inputs: Fixed gamepad support. Handle gamepad disconnection. Added ImGui_ImplSDL3_SetGamepadMode().
 //  2023-11-13: Updated for recent SDL3 API changes.
@@ -72,9 +94,15 @@
 struct ImGui_ImplSDL3_Data
 {
     SDL_Window*             Window;
+    SDL_WindowID            WindowID;
     SDL_Renderer*           Renderer;
     Uint64                  Time;
     char*                   ClipboardTextData;
+    bool                    UseVulkan;
+    bool                    WantUpdateMonitors;
+
+    // IME handling
+    SDL_Window*             ImeWindow;
 
     // Mouse handling
     Uint32                  MouseWindowID;
@@ -83,11 +111,12 @@ struct ImGui_ImplSDL3_Data
     SDL_Cursor*             MouseLastCursor;
     int                     MousePendingLeaveFrame;
     bool                    MouseCanUseGlobalState;
+    bool                    MouseCanReportHoveredViewport;  // This is hard to use/unreliable on SDL so we'll set ImGuiBackendFlags_HasMouseHoveredViewport dynamically based on state.
 
     // Gamepad handling
-    ImVector<SDL_Gamepad*>      Gamepads;
+    ImVector<SDL_Gamepad*>  Gamepads;
     ImGui_ImplSDL3_GamepadMode  GamepadMode;
-    bool                        WantUpdateGamepadsList;
+    bool                    WantUpdateGamepadsList;
 
     ImGui_ImplSDL3_Data()   { memset((void*)this, 0, sizeof(*this)); }
 };
@@ -101,41 +130,76 @@ static ImGui_ImplSDL3_Data* ImGui_ImplSDL3_GetBackendData()
     return ImGui::GetCurrentContext() ? (ImGui_ImplSDL3_Data*)ImGui::GetIO().BackendPlatformUserData : nullptr;
 }
 
+// Forward Declarations
+static void ImGui_ImplSDL3_UpdateMonitors();
+static void ImGui_ImplSDL3_InitMultiViewportSupport(SDL_Window* window, void* sdl_gl_context);
+static void ImGui_ImplSDL3_ShutdownMultiViewportSupport();
+
 // Functions
-static const char* ImGui_ImplSDL3_GetClipboardText(void*)
+static const char* ImGui_ImplSDL3_GetClipboardText(ImGuiContext*)
 {
     ImGui_ImplSDL3_Data* bd = ImGui_ImplSDL3_GetBackendData();
     if (bd->ClipboardTextData)
         SDL_free(bd->ClipboardTextData);
-    bd->ClipboardTextData = SDL_GetClipboardText();
+    const char* sdl_clipboard_text = SDL_GetClipboardText();
+    bd->ClipboardTextData = sdl_clipboard_text ? SDL_strdup(sdl_clipboard_text) : nullptr;
     return bd->ClipboardTextData;
 }
 
-static void ImGui_ImplSDL3_SetClipboardText(void*, const char* text)
+static void ImGui_ImplSDL3_SetClipboardText(ImGuiContext*, const char* text)
 {
     SDL_SetClipboardText(text);
 }
 
-static void ImGui_ImplSDL3_SetPlatformImeData(ImGuiViewport*, ImGuiPlatformImeData* data)
+static void ImGui_ImplSDL3_PlatformSetImeData(ImGuiContext*, ImGuiViewport* viewport, ImGuiPlatformImeData* data)
 {
+    ImGui_ImplSDL3_Data* bd = ImGui_ImplSDL3_GetBackendData();
+    SDL_WindowID window_id = (SDL_WindowID)(intptr_t)viewport->PlatformHandle;
+    SDL_Window* window = SDL_GetWindowFromID(window_id);
+    if ((data->WantVisible == false || bd->ImeWindow != window) && bd->ImeWindow != nullptr)
+    {
+        SDL_StopTextInput(bd->ImeWindow);
+        bd->ImeWindow = nullptr;
+    }
     if (data->WantVisible)
     {
         SDL_Rect r;
-        r.x = (int)data->InputPos.x;
-        r.y = (int)data->InputPos.y;
+        r.x = (int)(data->InputPos.x - viewport->Pos.x);
+        r.y = (int)(data->InputPos.y - viewport->Pos.y + data->InputLineHeight);
         r.w = 1;
         r.h = (int)data->InputLineHeight;
-        SDL_SetTextInputRect(&r);
-        SDL_StartTextInput();
-    }
-    else
-    {
-        SDL_StopTextInput();
+        SDL_SetTextInputArea(window, &r, 0);
+        SDL_StartTextInput(window);
+        bd->ImeWindow = window;
     }
 }
 
-static ImGuiKey ImGui_ImplSDL3_KeycodeToImGuiKey(int keycode)
+// Not static to allow third-party code to use that if they want to (but undocumented)
+ImGuiKey ImGui_ImplSDL3_KeyEventToImGuiKey(SDL_Keycode keycode, SDL_Scancode scancode);
+ImGuiKey ImGui_ImplSDL3_KeyEventToImGuiKey(SDL_Keycode keycode, SDL_Scancode scancode)
 {
+    // Keypad doesn't have individual key values in SDL3
+    switch (scancode)
+    {
+        case SDL_SCANCODE_KP_0: return ImGuiKey_Keypad0;
+        case SDL_SCANCODE_KP_1: return ImGuiKey_Keypad1;
+        case SDL_SCANCODE_KP_2: return ImGuiKey_Keypad2;
+        case SDL_SCANCODE_KP_3: return ImGuiKey_Keypad3;
+        case SDL_SCANCODE_KP_4: return ImGuiKey_Keypad4;
+        case SDL_SCANCODE_KP_5: return ImGuiKey_Keypad5;
+        case SDL_SCANCODE_KP_6: return ImGuiKey_Keypad6;
+        case SDL_SCANCODE_KP_7: return ImGuiKey_Keypad7;
+        case SDL_SCANCODE_KP_8: return ImGuiKey_Keypad8;
+        case SDL_SCANCODE_KP_9: return ImGuiKey_Keypad9;
+        case SDL_SCANCODE_KP_PERIOD: return ImGuiKey_KeypadDecimal;
+        case SDL_SCANCODE_KP_DIVIDE: return ImGuiKey_KeypadDivide;
+        case SDL_SCANCODE_KP_MULTIPLY: return ImGuiKey_KeypadMultiply;
+        case SDL_SCANCODE_KP_MINUS: return ImGuiKey_KeypadSubtract;
+        case SDL_SCANCODE_KP_PLUS: return ImGuiKey_KeypadAdd;
+        case SDL_SCANCODE_KP_ENTER: return ImGuiKey_KeypadEnter;
+        case SDL_SCANCODE_KP_EQUALS: return ImGuiKey_KeypadEqual;
+        default: break;
+    }
     switch (keycode)
     {
         case SDLK_TAB: return ImGuiKey_Tab;
@@ -169,23 +233,6 @@ static ImGuiKey ImGui_ImplSDL3_KeycodeToImGuiKey(int keycode)
         case SDLK_NUMLOCKCLEAR: return ImGuiKey_NumLock;
         case SDLK_PRINTSCREEN: return ImGuiKey_PrintScreen;
         case SDLK_PAUSE: return ImGuiKey_Pause;
-        case SDLK_KP_0: return ImGuiKey_Keypad0;
-        case SDLK_KP_1: return ImGuiKey_Keypad1;
-        case SDLK_KP_2: return ImGuiKey_Keypad2;
-        case SDLK_KP_3: return ImGuiKey_Keypad3;
-        case SDLK_KP_4: return ImGuiKey_Keypad4;
-        case SDLK_KP_5: return ImGuiKey_Keypad5;
-        case SDLK_KP_6: return ImGuiKey_Keypad6;
-        case SDLK_KP_7: return ImGuiKey_Keypad7;
-        case SDLK_KP_8: return ImGuiKey_Keypad8;
-        case SDLK_KP_9: return ImGuiKey_Keypad9;
-        case SDLK_KP_PERIOD: return ImGuiKey_KeypadDecimal;
-        case SDLK_KP_DIVIDE: return ImGuiKey_KeypadDivide;
-        case SDLK_KP_MULTIPLY: return ImGuiKey_KeypadMultiply;
-        case SDLK_KP_MINUS: return ImGuiKey_KeypadSubtract;
-        case SDLK_KP_PLUS: return ImGuiKey_KeypadAdd;
-        case SDLK_KP_ENTER: return ImGuiKey_KeypadEnter;
-        case SDLK_KP_EQUALS: return ImGuiKey_KeypadEqual;
         case SDLK_LCTRL: return ImGuiKey_LeftCtrl;
         case SDLK_LSHIFT: return ImGuiKey_LeftShift;
         case SDLK_LALT: return ImGuiKey_LeftAlt;
@@ -205,32 +252,32 @@ static ImGuiKey ImGui_ImplSDL3_KeycodeToImGuiKey(int keycode)
         case SDLK_7: return ImGuiKey_7;
         case SDLK_8: return ImGuiKey_8;
         case SDLK_9: return ImGuiKey_9;
-        case SDLK_a: return ImGuiKey_A;
-        case SDLK_b: return ImGuiKey_B;
-        case SDLK_c: return ImGuiKey_C;
-        case SDLK_d: return ImGuiKey_D;
-        case SDLK_e: return ImGuiKey_E;
-        case SDLK_f: return ImGuiKey_F;
-        case SDLK_g: return ImGuiKey_G;
-        case SDLK_h: return ImGuiKey_H;
-        case SDLK_i: return ImGuiKey_I;
-        case SDLK_j: return ImGuiKey_J;
-        case SDLK_k: return ImGuiKey_K;
-        case SDLK_l: return ImGuiKey_L;
-        case SDLK_m: return ImGuiKey_M;
-        case SDLK_n: return ImGuiKey_N;
-        case SDLK_o: return ImGuiKey_O;
-        case SDLK_p: return ImGuiKey_P;
-        case SDLK_q: return ImGuiKey_Q;
-        case SDLK_r: return ImGuiKey_R;
-        case SDLK_s: return ImGuiKey_S;
-        case SDLK_t: return ImGuiKey_T;
-        case SDLK_u: return ImGuiKey_U;
-        case SDLK_v: return ImGuiKey_V;
-        case SDLK_w: return ImGuiKey_W;
-        case SDLK_x: return ImGuiKey_X;
-        case SDLK_y: return ImGuiKey_Y;
-        case SDLK_z: return ImGuiKey_Z;
+        case SDLK_A: return ImGuiKey_A;
+        case SDLK_B: return ImGuiKey_B;
+        case SDLK_C: return ImGuiKey_C;
+        case SDLK_D: return ImGuiKey_D;
+        case SDLK_E: return ImGuiKey_E;
+        case SDLK_F: return ImGuiKey_F;
+        case SDLK_G: return ImGuiKey_G;
+        case SDLK_H: return ImGuiKey_H;
+        case SDLK_I: return ImGuiKey_I;
+        case SDLK_J: return ImGuiKey_J;
+        case SDLK_K: return ImGuiKey_K;
+        case SDLK_L: return ImGuiKey_L;
+        case SDLK_M: return ImGuiKey_M;
+        case SDLK_N: return ImGuiKey_N;
+        case SDLK_O: return ImGuiKey_O;
+        case SDLK_P: return ImGuiKey_P;
+        case SDLK_Q: return ImGuiKey_Q;
+        case SDLK_R: return ImGuiKey_R;
+        case SDLK_S: return ImGuiKey_S;
+        case SDLK_T: return ImGuiKey_T;
+        case SDLK_U: return ImGuiKey_U;
+        case SDLK_V: return ImGuiKey_V;
+        case SDLK_W: return ImGuiKey_W;
+        case SDLK_X: return ImGuiKey_X;
+        case SDLK_Y: return ImGuiKey_Y;
+        case SDLK_Z: return ImGuiKey_Z;
         case SDLK_F1: return ImGuiKey_F1;
         case SDLK_F2: return ImGuiKey_F2;
         case SDLK_F3: return ImGuiKey_F3;
@@ -257,6 +304,7 @@ static ImGuiKey ImGui_ImplSDL3_KeycodeToImGuiKey(int keycode)
         case SDLK_F24: return ImGuiKey_F24;
         case SDLK_AC_BACK: return ImGuiKey_AppBack;
         case SDLK_AC_FORWARD: return ImGuiKey_AppForward;
+        default: break;
     }
     return ImGuiKey_None;
 }
@@ -270,11 +318,15 @@ static void ImGui_ImplSDL3_UpdateKeyModifiers(SDL_Keymod sdl_key_mods)
     io.AddKeyEvent(ImGuiMod_Super, (sdl_key_mods & SDL_KMOD_GUI) != 0);
 }
 
+static ImGuiViewport* ImGui_ImplSDL3_GetViewportForWindowID(SDL_WindowID window_id)
+{
+    return ImGui::FindViewportByPlatformHandle((void*)(intptr_t)window_id);
+}
+
 // You can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if dear imgui wants to use your inputs.
 // - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application, or clear/overwrite your copy of the mouse data.
 // - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application, or clear/overwrite your copy of the keyboard data.
 // Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
-// If you have multiple SDL events and some of them are not meant to be used by dear imgui, you may need to filter events based on their windowID field.
 bool ImGui_ImplSDL3_ProcessEvent(const SDL_Event* event)
 {
     ImGui_ImplSDL3_Data* bd = ImGui_ImplSDL3_GetBackendData();
@@ -285,19 +337,27 @@ bool ImGui_ImplSDL3_ProcessEvent(const SDL_Event* event)
     {
         case SDL_EVENT_MOUSE_MOTION:
         {
+            if (ImGui_ImplSDL3_GetViewportForWindowID(event->motion.windowID) == nullptr)
+                return false;
             ImVec2 mouse_pos((float)event->motion.x, (float)event->motion.y);
+            if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+            {
+                int window_x, window_y;
+                SDL_GetWindowPosition(SDL_GetWindowFromID(event->motion.windowID), &window_x, &window_y);
+                mouse_pos.x += window_x;
+                mouse_pos.y += window_y;
+            }
             io.AddMouseSourceEvent(event->motion.which == SDL_TOUCH_MOUSEID ? ImGuiMouseSource_TouchScreen : ImGuiMouseSource_Mouse);
             io.AddMousePosEvent(mouse_pos.x, mouse_pos.y);
             return true;
         }
         case SDL_EVENT_MOUSE_WHEEL:
         {
+            if (ImGui_ImplSDL3_GetViewportForWindowID(event->wheel.windowID) == nullptr)
+                return false;
             //IMGUI_DEBUG_LOG("wheel %.2f %.2f, precise %.2f %.2f\n", (float)event->wheel.x, (float)event->wheel.y, event->wheel.preciseX, event->wheel.preciseY);
             float wheel_x = -event->wheel.x;
             float wheel_y = event->wheel.y;
-    #ifdef __EMSCRIPTEN__
-            wheel_x /= 100.0f;
-    #endif
             io.AddMouseSourceEvent(event->wheel.which == SDL_TOUCH_MOUSEID ? ImGuiMouseSource_TouchScreen : ImGuiMouseSource_Mouse);
             io.AddMouseWheelEvent(wheel_x, wheel_y);
             return true;
@@ -305,6 +365,8 @@ bool ImGui_ImplSDL3_ProcessEvent(const SDL_Event* event)
         case SDL_EVENT_MOUSE_BUTTON_DOWN:
         case SDL_EVENT_MOUSE_BUTTON_UP:
         {
+            if (ImGui_ImplSDL3_GetViewportForWindowID(event->button.windowID) == nullptr)
+                return false;
             int mouse_button = -1;
             if (event->button.button == SDL_BUTTON_LEFT) { mouse_button = 0; }
             if (event->button.button == SDL_BUTTON_RIGHT) { mouse_button = 1; }
@@ -320,20 +382,36 @@ bool ImGui_ImplSDL3_ProcessEvent(const SDL_Event* event)
         }
         case SDL_EVENT_TEXT_INPUT:
         {
+            if (ImGui_ImplSDL3_GetViewportForWindowID(event->text.windowID) == nullptr)
+                return false;
             io.AddInputCharactersUTF8(event->text.text);
             return true;
         }
         case SDL_EVENT_KEY_DOWN:
         case SDL_EVENT_KEY_UP:
         {
-            ImGui_ImplSDL3_UpdateKeyModifiers((SDL_Keymod)event->key.keysym.mod);
-            ImGuiKey key = ImGui_ImplSDL3_KeycodeToImGuiKey(event->key.keysym.sym);
+            if (ImGui_ImplSDL3_GetViewportForWindowID(event->key.windowID) == nullptr)
+                return false;
+            //IMGUI_DEBUG_LOG("SDL_EVENT_KEY_%d: key=%d, scancode=%d, mod=%X\n", (event->type == SDL_EVENT_KEY_DOWN) ? "DOWN" : "UP", event->key.key, event->key.scancode, event->key.mod);
+            ImGui_ImplSDL3_UpdateKeyModifiers((SDL_Keymod)event->key.mod);
+            ImGuiKey key = ImGui_ImplSDL3_KeyEventToImGuiKey(event->key.key, event->key.scancode);
             io.AddKeyEvent(key, (event->type == SDL_EVENT_KEY_DOWN));
-            io.SetKeyEventNativeData(key, event->key.keysym.sym, event->key.keysym.scancode, event->key.keysym.scancode); // To support legacy indexing (<1.87 user code). Legacy backend uses SDLK_*** as indices to IsKeyXXX() functions.
+            io.SetKeyEventNativeData(key, event->key.key, event->key.scancode, event->key.scancode); // To support legacy indexing (<1.87 user code). Legacy backend uses SDLK_*** as indices to IsKeyXXX() functions.
+            return true;
+        }
+        case SDL_EVENT_DISPLAY_ORIENTATION:
+        case SDL_EVENT_DISPLAY_ADDED:
+        case SDL_EVENT_DISPLAY_REMOVED:
+        case SDL_EVENT_DISPLAY_MOVED:
+        case SDL_EVENT_DISPLAY_CONTENT_SCALE_CHANGED:
+        {
+            bd->WantUpdateMonitors = true;
             return true;
         }
         case SDL_EVENT_WINDOW_MOUSE_ENTER:
         {
+            if (ImGui_ImplSDL3_GetViewportForWindowID(event->window.windowID) == nullptr)
+                return false;
             bd->MouseWindowID = event->window.windowID;
             bd->MousePendingLeaveFrame = 0;
             return true;
@@ -344,15 +422,34 @@ bool ImGui_ImplSDL3_ProcessEvent(const SDL_Event* event)
         // FIXME: Unconfirmed whether this is still needed with SDL3.
         case SDL_EVENT_WINDOW_MOUSE_LEAVE:
         {
+            if (ImGui_ImplSDL3_GetViewportForWindowID(event->window.windowID) == nullptr)
+                return false;
             bd->MousePendingLeaveFrame = ImGui::GetFrameCount() + 1;
             return true;
         }
         case SDL_EVENT_WINDOW_FOCUS_GAINED:
-            io.AddFocusEvent(true);
-            return true;
         case SDL_EVENT_WINDOW_FOCUS_LOST:
-            io.AddFocusEvent(false);
+        {
+            if (ImGui_ImplSDL3_GetViewportForWindowID(event->window.windowID) == nullptr)
+                return false;
+            io.AddFocusEvent(event->type == SDL_EVENT_WINDOW_FOCUS_GAINED);
             return true;
+        }
+        case SDL_EVENT_WINDOW_CLOSE_REQUESTED:
+        case SDL_EVENT_WINDOW_MOVED:
+        case SDL_EVENT_WINDOW_RESIZED:
+        {
+            ImGuiViewport* viewport = ImGui_ImplSDL3_GetViewportForWindowID(event->window.windowID);
+            if (viewport == NULL)
+                return false;
+            if (event->type == SDL_EVENT_WINDOW_CLOSE_REQUESTED)
+                viewport->PlatformRequestClose = true;
+            if (event->type == SDL_EVENT_WINDOW_MOVED)
+                viewport->PlatformRequestMove = true;
+            if (event->type == SDL_EVENT_WINDOW_RESIZED)
+                viewport->PlatformRequestResize = true;
+            return true;
+        }
         case SDL_EVENT_GAMEPAD_ADDED:
         case SDL_EVENT_GAMEPAD_REMOVED:
         {
@@ -365,12 +462,12 @@ bool ImGui_ImplSDL3_ProcessEvent(const SDL_Event* event)
 
 static void ImGui_ImplSDL3_SetupPlatformHandles(ImGuiViewport* viewport, SDL_Window* window)
 {
-    IM_UNUSED(window);
+    viewport->PlatformHandle = (void*)(intptr_t)SDL_GetWindowID(window);
     viewport->PlatformHandleRaw = nullptr;
-#if defined(__WIN32__) && !defined(__WINRT__)
-    viewport->PlatformHandleRaw = (HWND)SDL_GetProperty(SDL_GetWindowProperties(window), "SDL.window.win32.hwnd", nullptr);
+#if defined(_WIN32) && !defined(__WINRT__)
+    viewport->PlatformHandleRaw = (HWND)SDL_GetPointerProperty(SDL_GetWindowProperties(window), SDL_PROP_WINDOW_WIN32_HWND_POINTER, nullptr);
 #elif defined(__APPLE__) && defined(SDL_VIDEO_DRIVER_COCOA)
-    viewport->PlatformHandleRaw = (void*)SDL_GetProperty(SDL_GetWindowProperties(window), "SDL.window.cocoa.window", nullptr);
+    viewport->PlatformHandleRaw = SDL_GetPointerProperty(SDL_GetWindowProperties(window), SDL_PROP_WINDOW_COCOA_WINDOW_POINTER, nullptr);
 #endif
 }
 
@@ -398,15 +495,29 @@ static bool ImGui_ImplSDL3_Init(SDL_Window* window, SDL_Renderer* renderer, void
     io.BackendPlatformName = "imgui_impl_sdl3";
     io.BackendFlags |= ImGuiBackendFlags_HasMouseCursors;           // We can honor GetMouseCursor() values (optional)
     io.BackendFlags |= ImGuiBackendFlags_HasSetMousePos;            // We can honor io.WantSetMousePos requests (optional, rarely used)
+    if (mouse_can_use_global_state)
+        io.BackendFlags |= ImGuiBackendFlags_PlatformHasViewports;  // We can create multi-viewports on the Platform side (optional)
 
     bd->Window = window;
+    bd->WindowID = SDL_GetWindowID(window);
     bd->Renderer = renderer;
-    bd->MouseCanUseGlobalState = mouse_can_use_global_state;
 
-    io.SetClipboardTextFn = ImGui_ImplSDL3_SetClipboardText;
-    io.GetClipboardTextFn = ImGui_ImplSDL3_GetClipboardText;
-    io.ClipboardUserData = nullptr;
-    io.SetPlatformImeDataFn = ImGui_ImplSDL3_SetPlatformImeData;
+    // SDL on Linux/OSX doesn't report events for unfocused windows (see https://github.com/ocornut/imgui/issues/4960)
+    // We will use 'MouseCanReportHoveredViewport' to set 'ImGuiBackendFlags_HasMouseHoveredViewport' dynamically each frame.
+    bd->MouseCanUseGlobalState = mouse_can_use_global_state;
+#ifndef __APPLE__
+    bd->MouseCanReportHoveredViewport = bd->MouseCanUseGlobalState;
+#else
+    bd->MouseCanReportHoveredViewport = false;
+#endif
+
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    platform_io.Platform_SetClipboardTextFn = ImGui_ImplSDL3_SetClipboardText;
+    platform_io.Platform_GetClipboardTextFn = ImGui_ImplSDL3_GetClipboardText;
+    platform_io.Platform_SetImeDataFn = ImGui_ImplSDL3_PlatformSetImeData;
+
+    // Update monitor a first time during init
+    ImGui_ImplSDL3_UpdateMonitors();
 
     // Gamepad handling
     bd->GamepadMode = ImGui_ImplSDL3_GamepadMode_AutoFirst;
@@ -433,27 +544,35 @@ static bool ImGui_ImplSDL3_Init(SDL_Window* window, SDL_Renderer* renderer, void
     // (This is unfortunately a global SDL setting, so enabling it might have a side-effect on your application.
     // It is unlikely to make a difference, but if your app absolutely needs to ignore the initial on-focus click:
     // you can ignore SDL_EVENT_MOUSE_BUTTON_DOWN events coming right after a SDL_WINDOWEVENT_FOCUS_GAINED)
-#ifdef SDL_HINT_MOUSE_FOCUS_CLICKTHROUGH
     SDL_SetHint(SDL_HINT_MOUSE_FOCUS_CLICKTHROUGH, "1");
-#endif
 
     // From 2.0.22: Disable auto-capture, this is preventing drag and drop across multiple windows (see #5710)
-#ifdef SDL_HINT_MOUSE_AUTO_CAPTURE
     SDL_SetHint(SDL_HINT_MOUSE_AUTO_CAPTURE, "0");
-#endif
+
+    // SDL 3.x : see https://github.com/libsdl-org/SDL/issues/6659
+    SDL_SetHint("SDL_BORDERLESS_WINDOWED_STYLE", "0");
+
+    // We need SDL_CaptureMouse(), SDL_GetGlobalMouseState() from SDL 2.0.4+ to support multiple viewports.
+    // We left the call to ImGui_ImplSDL3_InitPlatformInterface() outside of #ifdef to avoid unused-function warnings.
+    if (io.BackendFlags & ImGuiBackendFlags_PlatformHasViewports)
+        ImGui_ImplSDL3_InitMultiViewportSupport(window, sdl_gl_context);
 
     return true;
 }
 
+// Should technically be a SDL_GLContext but due to typedef it is sane to keep it void* in public interface.
 bool ImGui_ImplSDL3_InitForOpenGL(SDL_Window* window, void* sdl_gl_context)
 {
-    IM_UNUSED(sdl_gl_context); // Viewport branch will need this.
     return ImGui_ImplSDL3_Init(window, nullptr, sdl_gl_context);
 }
 
 bool ImGui_ImplSDL3_InitForVulkan(SDL_Window* window)
 {
-    return ImGui_ImplSDL3_Init(window, nullptr, nullptr);
+    if (!ImGui_ImplSDL3_Init(window, nullptr, nullptr))
+        return false;
+    ImGui_ImplSDL3_Data* bd = ImGui_ImplSDL3_GetBackendData();
+    bd->UseVulkan = true;
+    return true;
 }
 
 bool ImGui_ImplSDL3_InitForD3D(SDL_Window* window)
@@ -487,6 +606,8 @@ void ImGui_ImplSDL3_Shutdown()
     IM_ASSERT(bd != nullptr && "No platform backend to shutdown, or already shutdown?");
     ImGuiIO& io = ImGui::GetIO();
 
+    ImGui_ImplSDL3_ShutdownMultiViewportSupport();
+
     if (bd->ClipboardTextData)
         SDL_free(bd->ClipboardTextData);
     for (ImGuiMouseCursor cursor_n = 0; cursor_n < ImGuiMouseCursor_COUNT; cursor_n++)
@@ -495,10 +616,11 @@ void ImGui_ImplSDL3_Shutdown()
 
     io.BackendPlatformName = nullptr;
     io.BackendPlatformUserData = nullptr;
-    io.BackendFlags &= ~(ImGuiBackendFlags_HasMouseCursors | ImGuiBackendFlags_HasSetMousePos | ImGuiBackendFlags_HasGamepad);
+    io.BackendFlags &= ~(ImGuiBackendFlags_HasMouseCursors | ImGuiBackendFlags_HasSetMousePos | ImGuiBackendFlags_HasGamepad | ImGuiBackendFlags_PlatformHasViewports | ImGuiBackendFlags_HasMouseHoveredViewport);
     IM_DELETE(bd);
 }
 
+// This code is incredibly messy because some of the functions we need for full viewport support are not available in SDL < 2.0.4.
 static void ImGui_ImplSDL3_UpdateMouseData()
 {
     ImGui_ImplSDL3_Data* bd = ImGui_ImplSDL3_GetBackendData();
@@ -507,30 +629,58 @@ static void ImGui_ImplSDL3_UpdateMouseData()
     // We forward mouse input when hovered or captured (via SDL_EVENT_MOUSE_MOTION) or when focused (below)
 #if SDL_HAS_CAPTURE_AND_GLOBAL_MOUSE
     // SDL_CaptureMouse() let the OS know e.g. that our imgui drag outside the SDL window boundaries shouldn't e.g. trigger other operations outside
-    SDL_CaptureMouse((bd->MouseButtonsDown != 0) ? SDL_TRUE : SDL_FALSE);
+    SDL_CaptureMouse(bd->MouseButtonsDown != 0);
     SDL_Window* focused_window = SDL_GetKeyboardFocus();
-    const bool is_app_focused = (bd->Window == focused_window);
+    const bool is_app_focused = (focused_window && (bd->Window == focused_window || ImGui_ImplSDL3_GetViewportForWindowID(SDL_GetWindowID(focused_window)) != NULL));
 #else
     SDL_Window* focused_window = bd->Window;
     const bool is_app_focused = (SDL_GetWindowFlags(bd->Window) & SDL_WINDOW_INPUT_FOCUS) != 0; // SDL 2.0.3 and non-windowed systems: single-viewport only
 #endif
     if (is_app_focused)
     {
-        // (Optional) Set OS mouse position from Dear ImGui if requested (rarely used, only when ImGuiConfigFlags_NavEnableSetMousePos is enabled by user)
+        // (Optional) Set OS mouse position from Dear ImGui if requested (rarely used, only when io.ConfigNavMoveSetMousePos is enabled by user)
         if (io.WantSetMousePos)
-            SDL_WarpMouseInWindow(bd->Window, io.MousePos.x, io.MousePos.y);
+        {
+#if SDL_HAS_CAPTURE_AND_GLOBAL_MOUSE
+            if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+                SDL_WarpMouseGlobal(io.MousePos.x, io.MousePos.y);
+            else
+#endif
+                SDL_WarpMouseInWindow(bd->Window, io.MousePos.x, io.MousePos.y);
+        }
 
         // (Optional) Fallback to provide mouse position when focused (SDL_EVENT_MOUSE_MOTION already provides this when hovered or captured)
         if (bd->MouseCanUseGlobalState && bd->MouseButtonsDown == 0)
         {
             // Single-viewport mode: mouse position in client window coordinates (io.MousePos is (0,0) when the mouse is on the upper-left corner of the app window)
-            float mouse_x_global, mouse_y_global;
+            // Multi-viewport mode: mouse position in OS absolute coordinates (io.MousePos is (0,0) when the mouse is on the upper-left of the primary monitor)
+            float mouse_x, mouse_y;
             int window_x, window_y;
-            SDL_GetGlobalMouseState(&mouse_x_global, &mouse_y_global);
-            SDL_GetWindowPosition(focused_window, &window_x, &window_y);
-            io.AddMousePosEvent(mouse_x_global - window_x, mouse_y_global - window_y);
+            SDL_GetGlobalMouseState(&mouse_x, &mouse_y);
+            if (!(io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable))
+            {
+                SDL_GetWindowPosition(focused_window, &window_x, &window_y);
+                mouse_x -= window_x;
+                mouse_y -= window_y;
+            }
+            io.AddMousePosEvent((float)mouse_x, (float)mouse_y);
         }
     }
+
+    // (Optional) When using multiple viewports: call io.AddMouseViewportEvent() with the viewport the OS mouse cursor is hovering.
+    // If ImGuiBackendFlags_HasMouseHoveredViewport is not set by the backend, Dear imGui will ignore this field and infer the information using its flawed heuristic.
+    // - [!] SDL backend does NOT correctly ignore viewports with the _NoInputs flag.
+    //       Some backend are not able to handle that correctly. If a backend report an hovered viewport that has the _NoInputs flag (e.g. when dragging a window
+    //       for docking, the viewport has the _NoInputs flag in order to allow us to find the viewport under), then Dear ImGui is forced to ignore the value reported
+    //       by the backend, and use its flawed heuristic to guess the viewport behind.
+    // - [X] SDL backend correctly reports this regardless of another viewport behind focused and dragged from (we need this to find a useful drag and drop target).
+    if (io.BackendFlags & ImGuiBackendFlags_HasMouseHoveredViewport)
+    {
+        ImGuiID mouse_viewport_id = 0;
+        if (ImGuiViewport* mouse_viewport = ImGui_ImplSDL3_GetViewportForWindowID(bd->MouseWindowID))
+            mouse_viewport_id = mouse_viewport->ID;
+        io.AddMouseViewportEvent(mouse_viewport_id);
+    }
 }
 
 static void ImGui_ImplSDL3_UpdateMouseCursor()
@@ -625,8 +775,8 @@ static void ImGui_ImplSDL3_UpdateGamepads()
                 if (bd->GamepadMode == ImGui_ImplSDL3_GamepadMode_AutoFirst)
                     break;
             }
-        SDL_free(sdl_gamepads);
         bd->WantUpdateGamepadsList = false;
+        SDL_free(sdl_gamepads);
     }
 
     // FIXME: Technically feeding gamepad shouldn't depend on this now that they are regular inputs.
@@ -665,6 +815,38 @@ static void ImGui_ImplSDL3_UpdateGamepads()
     ImGui_ImplSDL3_UpdateGamepadAnalog(bd, io, ImGuiKey_GamepadRStickDown,  SDL_GAMEPAD_AXIS_RIGHTY, +thumb_dead_zone, +32767);
 }
 
+static void ImGui_ImplSDL3_UpdateMonitors()
+{
+    ImGui_ImplSDL3_Data* bd = ImGui_ImplSDL3_GetBackendData();
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    platform_io.Monitors.resize(0);
+    bd->WantUpdateMonitors = false;
+
+    int display_count;
+    SDL_DisplayID* displays = SDL_GetDisplays(&display_count);
+    for (int n = 0; n < display_count; n++)
+    {
+        // Warning: the validity of monitor DPI information on Windows depends on the application DPI awareness settings, which generally needs to be set in the manifest or at runtime.
+        SDL_DisplayID display_id = displays[n];
+        ImGuiPlatformMonitor monitor;
+        SDL_Rect r;
+        SDL_GetDisplayBounds(display_id, &r);
+        monitor.MainPos = monitor.WorkPos = ImVec2((float)r.x, (float)r.y);
+        monitor.MainSize = monitor.WorkSize = ImVec2((float)r.w, (float)r.h);
+        SDL_GetDisplayUsableBounds(display_id, &r);
+        monitor.WorkPos = ImVec2((float)r.x, (float)r.y);
+        monitor.WorkSize = ImVec2((float)r.w, (float)r.h);
+        // FIXME-VIEWPORT: On MacOS SDL reports actual monitor DPI scale, ignoring OS configuration. We may want to set
+        //  DpiScale to cocoa_window.backingScaleFactor here.
+        monitor.DpiScale = SDL_GetDisplayContentScale(display_id);
+        monitor.PlatformHandle = (void*)(intptr_t)n;
+        if (monitor.DpiScale <= 0.0f)
+            continue; // Some accessibility applications are declaring virtual monitors with a DPI of 0, see #7902.
+        platform_io.Monitors.push_back(monitor);
+    }
+    SDL_free(displays);
+}
+
 void ImGui_ImplSDL3_NewFrame()
 {
     ImGui_ImplSDL3_Data* bd = ImGui_ImplSDL3_GetBackendData();
@@ -682,6 +864,10 @@ void ImGui_ImplSDL3_NewFrame()
     if (w > 0 && h > 0)
         io.DisplayFramebufferScale = ImVec2((float)display_w / w, (float)display_h / h);
 
+    // Update monitors
+    if (bd->WantUpdateMonitors)
+        ImGui_ImplSDL3_UpdateMonitors();
+
     // Setup time step (we don't use SDL_GetTicks() because it is using millisecond resolution)
     // (Accept SDL_GetPerformanceCounter() not returning a monotonically increasing value. Happens in VMs and Emscripten, see #6189, #6114, #3644)
     static Uint64 frequency = SDL_GetPerformanceFrequency();
@@ -698,6 +884,13 @@ void ImGui_ImplSDL3_NewFrame()
         io.AddMousePosEvent(-FLT_MAX, -FLT_MAX);
     }
 
+    // Our io.AddMouseViewportEvent() calls will only be valid when not capturing.
+    // Technically speaking testing for 'bd->MouseButtonsDown == 0' would be more rigorous, but testing for payload reduces noise and potential side-effects.
+    if (bd->MouseCanReportHoveredViewport && ImGui::GetDragDropPayload() == nullptr)
+        io.BackendFlags |= ImGuiBackendFlags_HasMouseHoveredViewport;
+    else
+        io.BackendFlags &= ~ImGuiBackendFlags_HasMouseHoveredViewport;
+
     ImGui_ImplSDL3_UpdateMouseData();
     ImGui_ImplSDL3_UpdateMouseCursor();
 
@@ -705,6 +898,254 @@ void ImGui_ImplSDL3_NewFrame()
     ImGui_ImplSDL3_UpdateGamepads();
 }
 
+//--------------------------------------------------------------------------------------------------------
+// MULTI-VIEWPORT / PLATFORM INTERFACE SUPPORT
+// This is an _advanced_ and _optional_ feature, allowing the backend to create and handle multiple viewports simultaneously.
+// If you are new to dear imgui or creating a new binding for dear imgui, it is recommended that you completely ignore this section first..
+//--------------------------------------------------------------------------------------------------------
+
+// Helper structure we store in the void* RendererUserData field of each ImGuiViewport to easily retrieve our backend data.
+struct ImGui_ImplSDL3_ViewportData
+{
+    SDL_Window*     Window;
+    SDL_Window*     ParentWindow;
+    Uint32          WindowID;
+    bool            WindowOwned;
+    SDL_GLContext   GLContext;
+
+    ImGui_ImplSDL3_ViewportData() { Window = ParentWindow = nullptr; WindowID = 0; WindowOwned = false; GLContext = nullptr; }
+    ~ImGui_ImplSDL3_ViewportData() { IM_ASSERT(Window == nullptr && GLContext == nullptr); }
+};
+
+static SDL_Window* ImGui_ImplSDL3_GetSDLWindowFromViewportID(ImGuiID viewport_id)
+{
+    if (viewport_id != 0)
+        if (ImGuiViewport* viewport = ImGui::FindViewportByID(viewport_id))
+        {
+            SDL_WindowID window_id = (SDL_WindowID)(intptr_t)viewport->PlatformHandle;
+            return SDL_GetWindowFromID(window_id);
+        }
+    return nullptr;
+}
+
+static void ImGui_ImplSDL3_CreateWindow(ImGuiViewport* viewport)
+{
+    ImGui_ImplSDL3_Data* bd = ImGui_ImplSDL3_GetBackendData();
+    ImGui_ImplSDL3_ViewportData* vd = IM_NEW(ImGui_ImplSDL3_ViewportData)();
+    viewport->PlatformUserData = vd;
+
+    vd->ParentWindow = ImGui_ImplSDL3_GetSDLWindowFromViewportID(viewport->ParentViewportId);
+
+    ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+    ImGui_ImplSDL3_ViewportData* main_viewport_data = (ImGui_ImplSDL3_ViewportData*)main_viewport->PlatformUserData;
+
+    // Share GL resources with main context
+    bool use_opengl = (main_viewport_data->GLContext != nullptr);
+    SDL_GLContext backup_context = nullptr;
+    if (use_opengl)
+    {
+        backup_context = SDL_GL_GetCurrentContext();
+        SDL_GL_SetAttribute(SDL_GL_SHARE_WITH_CURRENT_CONTEXT, 1);
+        SDL_GL_MakeCurrent(main_viewport_data->Window, main_viewport_data->GLContext);
+    }
+
+    SDL_WindowFlags sdl_flags = 0;
+    sdl_flags |= use_opengl ? SDL_WINDOW_OPENGL : (bd->UseVulkan ? SDL_WINDOW_VULKAN : 0);
+    sdl_flags |= SDL_GetWindowFlags(bd->Window) & SDL_WINDOW_HIGH_PIXEL_DENSITY;
+    sdl_flags |= (viewport->Flags & ImGuiViewportFlags_NoDecoration) ? SDL_WINDOW_BORDERLESS : 0;
+    sdl_flags |= (viewport->Flags & ImGuiViewportFlags_NoDecoration) ? 0 : SDL_WINDOW_RESIZABLE;
+    sdl_flags |= (viewport->Flags & ImGuiViewportFlags_NoTaskBarIcon) ? SDL_WINDOW_UTILITY : 0;
+    sdl_flags |= (viewport->Flags & ImGuiViewportFlags_TopMost) ? SDL_WINDOW_ALWAYS_ON_TOP : 0;
+    vd->Window = SDL_CreateWindow("No Title Yet", (int)viewport->Size.x, (int)viewport->Size.y, sdl_flags);
+    SDL_SetWindowParent(vd->Window, vd->ParentWindow);
+    SDL_SetWindowPosition(vd->Window, (int)viewport->Pos.x, (int)viewport->Pos.y);
+    vd->WindowOwned = true;
+    if (use_opengl)
+    {
+        vd->GLContext = SDL_GL_CreateContext(vd->Window);
+        SDL_GL_SetSwapInterval(0);
+    }
+    if (use_opengl && backup_context)
+        SDL_GL_MakeCurrent(vd->Window, backup_context);
+
+    ImGui_ImplSDL3_SetupPlatformHandles(viewport, vd->Window);
+}
+
+static void ImGui_ImplSDL3_DestroyWindow(ImGuiViewport* viewport)
+{
+    if (ImGui_ImplSDL3_ViewportData* vd = (ImGui_ImplSDL3_ViewportData*)viewport->PlatformUserData)
+    {
+        if (vd->GLContext && vd->WindowOwned)
+            SDL_GL_DestroyContext(vd->GLContext);
+        if (vd->Window && vd->WindowOwned)
+            SDL_DestroyWindow(vd->Window);
+        vd->GLContext = nullptr;
+        vd->Window = nullptr;
+        IM_DELETE(vd);
+    }
+    viewport->PlatformUserData = viewport->PlatformHandle = nullptr;
+}
+
+static void ImGui_ImplSDL3_ShowWindow(ImGuiViewport* viewport)
+{
+    ImGui_ImplSDL3_ViewportData* vd = (ImGui_ImplSDL3_ViewportData*)viewport->PlatformUserData;
+#if defined(_WIN32) && !(defined(WINAPI_FAMILY) && (WINAPI_FAMILY == WINAPI_FAMILY_APP || WINAPI_FAMILY == WINAPI_FAMILY_GAMES))
+    HWND hwnd = (HWND)viewport->PlatformHandleRaw;
+
+    // SDL hack: Show icon in task bar (#7989)
+    // Note: SDL_WINDOW_UTILITY can be used to control task bar visibility, but on Windows, it does not affect child windows.
+    if (!(viewport->Flags & ImGuiViewportFlags_NoTaskBarIcon))
+    {
+        LONG ex_style = ::GetWindowLong(hwnd, GWL_EXSTYLE);
+        ex_style |= WS_EX_APPWINDOW;
+        ex_style &= ~WS_EX_TOOLWINDOW;
+        ::ShowWindow(hwnd, SW_HIDE);
+        ::SetWindowLong(hwnd, GWL_EXSTYLE, ex_style);
+    }
+#endif
+
+    SDL_SetHint(SDL_HINT_WINDOW_ACTIVATE_WHEN_SHOWN, (viewport->Flags & ImGuiViewportFlags_NoFocusOnAppearing) ? "0" : "1");
+    SDL_ShowWindow(vd->Window);
+}
+
+static void ImGui_ImplSDL3_UpdateWindow(ImGuiViewport* viewport)
+{
+    ImGui_ImplSDL3_ViewportData* vd = (ImGui_ImplSDL3_ViewportData*)viewport->PlatformUserData;
+
+    // Update SDL3 parent if it changed _after_ creation.
+    // This is for advanced apps that are manipulating ParentViewportID manually.
+    SDL_Window* new_parent = ImGui_ImplSDL3_GetSDLWindowFromViewportID(viewport->ParentViewportId);
+    if (new_parent != vd->ParentWindow)
+    {
+        vd->ParentWindow = new_parent;
+        SDL_SetWindowParent(vd->Window, vd->ParentWindow);
+    }
+}
+
+static ImVec2 ImGui_ImplSDL3_GetWindowPos(ImGuiViewport* viewport)
+{
+    ImGui_ImplSDL3_ViewportData* vd = (ImGui_ImplSDL3_ViewportData*)viewport->PlatformUserData;
+    int x = 0, y = 0;
+    SDL_GetWindowPosition(vd->Window, &x, &y);
+    return ImVec2((float)x, (float)y);
+}
+
+static void ImGui_ImplSDL3_SetWindowPos(ImGuiViewport* viewport, ImVec2 pos)
+{
+    ImGui_ImplSDL3_ViewportData* vd = (ImGui_ImplSDL3_ViewportData*)viewport->PlatformUserData;
+    SDL_SetWindowPosition(vd->Window, (int)pos.x, (int)pos.y);
+}
+
+static ImVec2 ImGui_ImplSDL3_GetWindowSize(ImGuiViewport* viewport)
+{
+    ImGui_ImplSDL3_ViewportData* vd = (ImGui_ImplSDL3_ViewportData*)viewport->PlatformUserData;
+    int w = 0, h = 0;
+    SDL_GetWindowSize(vd->Window, &w, &h);
+    return ImVec2((float)w, (float)h);
+}
+
+static void ImGui_ImplSDL3_SetWindowSize(ImGuiViewport* viewport, ImVec2 size)
+{
+    ImGui_ImplSDL3_ViewportData* vd = (ImGui_ImplSDL3_ViewportData*)viewport->PlatformUserData;
+    SDL_SetWindowSize(vd->Window, (int)size.x, (int)size.y);
+}
+
+static void ImGui_ImplSDL3_SetWindowTitle(ImGuiViewport* viewport, const char* title)
+{
+    ImGui_ImplSDL3_ViewportData* vd = (ImGui_ImplSDL3_ViewportData*)viewport->PlatformUserData;
+    SDL_SetWindowTitle(vd->Window, title);
+}
+
+static void ImGui_ImplSDL3_SetWindowAlpha(ImGuiViewport* viewport, float alpha)
+{
+    ImGui_ImplSDL3_ViewportData* vd = (ImGui_ImplSDL3_ViewportData*)viewport->PlatformUserData;
+    SDL_SetWindowOpacity(vd->Window, alpha);
+}
+
+static void ImGui_ImplSDL3_SetWindowFocus(ImGuiViewport* viewport)
+{
+    ImGui_ImplSDL3_ViewportData* vd = (ImGui_ImplSDL3_ViewportData*)viewport->PlatformUserData;
+    SDL_RaiseWindow(vd->Window);
+}
+
+static bool ImGui_ImplSDL3_GetWindowFocus(ImGuiViewport* viewport)
+{
+    ImGui_ImplSDL3_ViewportData* vd = (ImGui_ImplSDL3_ViewportData*)viewport->PlatformUserData;
+    return (SDL_GetWindowFlags(vd->Window) & SDL_WINDOW_INPUT_FOCUS) != 0;
+}
+
+static bool ImGui_ImplSDL3_GetWindowMinimized(ImGuiViewport* viewport)
+{
+    ImGui_ImplSDL3_ViewportData* vd = (ImGui_ImplSDL3_ViewportData*)viewport->PlatformUserData;
+    return (SDL_GetWindowFlags(vd->Window) & SDL_WINDOW_MINIMIZED) != 0;
+}
+
+static void ImGui_ImplSDL3_RenderWindow(ImGuiViewport* viewport, void*)
+{
+    ImGui_ImplSDL3_ViewportData* vd = (ImGui_ImplSDL3_ViewportData*)viewport->PlatformUserData;
+    if (vd->GLContext)
+        SDL_GL_MakeCurrent(vd->Window, vd->GLContext);
+}
+
+static void ImGui_ImplSDL3_SwapBuffers(ImGuiViewport* viewport, void*)
+{
+    ImGui_ImplSDL3_ViewportData* vd = (ImGui_ImplSDL3_ViewportData*)viewport->PlatformUserData;
+    if (vd->GLContext)
+    {
+        SDL_GL_MakeCurrent(vd->Window, vd->GLContext);
+        SDL_GL_SwapWindow(vd->Window);
+    }
+}
+
+// Vulkan support (the Vulkan renderer needs to call a platform-side support function to create the surface)
+// SDL is graceful enough to _not_ need <vulkan/vulkan.h> so we can safely include this.
+#include <SDL3/SDL_vulkan.h>
+static int ImGui_ImplSDL3_CreateVkSurface(ImGuiViewport* viewport, ImU64 vk_instance, const void* vk_allocator, ImU64* out_vk_surface)
+{
+    ImGui_ImplSDL3_ViewportData* vd = (ImGui_ImplSDL3_ViewportData*)viewport->PlatformUserData;
+    (void)vk_allocator;
+    bool ret = SDL_Vulkan_CreateSurface(vd->Window, (VkInstance)vk_instance, (VkAllocationCallbacks*)vk_allocator, (VkSurfaceKHR*)out_vk_surface);
+    return ret ? 0 : 1; // ret ? VK_SUCCESS : VK_NOT_READY
+}
+
+static void ImGui_ImplSDL3_InitMultiViewportSupport(SDL_Window* window, void* sdl_gl_context)
+{
+    // Register platform interface (will be coupled with a renderer interface)
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    platform_io.Platform_CreateWindow = ImGui_ImplSDL3_CreateWindow;
+    platform_io.Platform_DestroyWindow = ImGui_ImplSDL3_DestroyWindow;
+    platform_io.Platform_ShowWindow = ImGui_ImplSDL3_ShowWindow;
+    platform_io.Platform_UpdateWindow = ImGui_ImplSDL3_UpdateWindow;
+    platform_io.Platform_SetWindowPos = ImGui_ImplSDL3_SetWindowPos;
+    platform_io.Platform_GetWindowPos = ImGui_ImplSDL3_GetWindowPos;
+    platform_io.Platform_SetWindowSize = ImGui_ImplSDL3_SetWindowSize;
+    platform_io.Platform_GetWindowSize = ImGui_ImplSDL3_GetWindowSize;
+    platform_io.Platform_SetWindowFocus = ImGui_ImplSDL3_SetWindowFocus;
+    platform_io.Platform_GetWindowFocus = ImGui_ImplSDL3_GetWindowFocus;
+    platform_io.Platform_GetWindowMinimized = ImGui_ImplSDL3_GetWindowMinimized;
+    platform_io.Platform_SetWindowTitle = ImGui_ImplSDL3_SetWindowTitle;
+    platform_io.Platform_RenderWindow = ImGui_ImplSDL3_RenderWindow;
+    platform_io.Platform_SwapBuffers = ImGui_ImplSDL3_SwapBuffers;
+    platform_io.Platform_SetWindowAlpha = ImGui_ImplSDL3_SetWindowAlpha;
+    platform_io.Platform_CreateVkSurface = ImGui_ImplSDL3_CreateVkSurface;
+
+    // Register main window handle (which is owned by the main application, not by us)
+    // This is mostly for simplicity and consistency, so that our code (e.g. mouse handling etc.) can use same logic for main and secondary viewports.
+    ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+    ImGui_ImplSDL3_ViewportData* vd = IM_NEW(ImGui_ImplSDL3_ViewportData)();
+    vd->Window = window;
+    vd->WindowID = SDL_GetWindowID(window);
+    vd->WindowOwned = false;
+    vd->GLContext = (SDL_GLContext)sdl_gl_context;
+    main_viewport->PlatformUserData = vd;
+    main_viewport->PlatformHandle = (void*)(intptr_t)vd->WindowID;
+}
+
+static void ImGui_ImplSDL3_ShutdownMultiViewportSupport()
+{
+    ImGui::DestroyPlatformWindows();
+}
+
 //-----------------------------------------------------------------------------
 
 #if defined(__clang__)

backends/imgui_impl_sdl3.h

@@ -1,16 +1,19 @@
 // dear imgui: Platform Backend for SDL3 (*EXPERIMENTAL*)
 // This needs to be used along with a Renderer (e.g. DirectX11, OpenGL3, Vulkan..)
 // (Info: SDL3 is a cross-platform general purpose library for handling windows, inputs, graphics context creation, etc.)
-// (IMPORTANT: SDL 3.0.0 is NOT YET RELEASED. IT IS POSSIBLE THAT ITS SPECS/API WILL CHANGE BEFORE RELEASE)
+
+// (**IMPORTANT: SDL 3.0.0 is NOT YET RELEASED AND CURRENTLY HAS A FAST CHANGING API. THIS CODE BREAKS OFTEN AS SDL3 CHANGES.**)
 
 // Implemented features:
 //  [X] Platform: Clipboard support.
 //  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen.
-//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy SDL_SCANCODE_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy SDL_SCANCODE_* values are obsolete since 1.87 and not supported since 1.91.5]
 //  [X] Platform: Gamepad support. Enabled with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
-//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
-// Missing features:
-//  [ ] Platform: IME SUPPORT IS BROKEN IN SDL3 BECAUSE INPUTS GETS SENT TO BOTH APP AND IME + app needs to call 'SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1");' before SDL_CreateWindow()!.
+//  [X] Platform: Mouse cursor shape and visibility (ImGuiBackendFlags_HasMouseCursors). Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+//  [x] Platform: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable' -> the OS animation effect when window gets created/destroyed is problematic. SDL2 backend doesn't have issue.
+// Missing features or Issues:
+//  [ ] Platform: Multi-viewport: Minimized windows seems to break mouse wheel events (at least under Windows).
+//  [x] Platform: IME support. Position somehow broken in SDL3 + app needs to call 'SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1");' before SDL_CreateWindow()!.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -29,6 +32,7 @@ struct SDL_Renderer;
 struct SDL_Gamepad;
 typedef union SDL_Event SDL_Event;
 
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
 IMGUI_IMPL_API bool     ImGui_ImplSDL3_InitForOpenGL(SDL_Window* window, void* sdl_gl_context);
 IMGUI_IMPL_API bool     ImGui_ImplSDL3_InitForVulkan(SDL_Window* window);
 IMGUI_IMPL_API bool     ImGui_ImplSDL3_InitForD3D(SDL_Window* window);
@@ -42,6 +46,6 @@ IMGUI_IMPL_API bool     ImGui_ImplSDL3_ProcessEvent(const SDL_Event* event);
 // Gamepad selection automatically starts in AutoFirst mode, picking first available SDL_Gamepad. You may override this.
 // When using manual mode, caller is responsible for opening/closing gamepad.
 enum ImGui_ImplSDL3_GamepadMode { ImGui_ImplSDL3_GamepadMode_AutoFirst, ImGui_ImplSDL3_GamepadMode_AutoAll, ImGui_ImplSDL3_GamepadMode_Manual };
-IMGUI_IMPL_API void     ImGui_ImplSDL3_SetGamepadMode(ImGui_ImplSDL3_GamepadMode mode, SDL_Gamepad** manual_gamepads_array = NULL, int manual_gamepads_count = -1);
+IMGUI_IMPL_API void     ImGui_ImplSDL3_SetGamepadMode(ImGui_ImplSDL3_GamepadMode mode, SDL_Gamepad** manual_gamepads_array = nullptr, int manual_gamepads_count = -1);
 
 #endif // #ifndef IMGUI_DISABLE

backends/imgui_impl_sdlrenderer2.cpp

@@ -9,7 +9,10 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'SDL_Texture*' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
+//  [X] Renderer: Expose selected render state for draw callbacks to use. Access in '(ImGui_ImplXXXX_RenderState*)GetPlatformIO().Renderer_RenderState'.
+// Missing features:
+//  [ ] Renderer: Multi-viewport support (multiple windows).
 
 // You can copy and use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -20,6 +23,7 @@
 // - Introduction, links and more at the top of imgui.cpp
 
 // CHANGELOG
+//  2024-10-09: Expose selected render state in ImGui_ImplSDLRenderer2_RenderState, which you can access in 'void* platform_io.Renderer_RenderState' during draw callbacks.
 //  2024-05-14: *BREAKING CHANGE* ImGui_ImplSDLRenderer3_RenderDrawData() requires SDL_Renderer* passed as parameter.
 //  2023-05-30: Renamed imgui_impl_sdlrenderer.h/.cpp to imgui_impl_sdlrenderer2.h/.cpp to accommodate for upcoming SDL3.
 //  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
@@ -140,21 +144,29 @@ void ImGui_ImplSDLRenderer2_RenderDrawData(ImDrawData* draw_data, SDL_Renderer*
     SDL_RenderGetViewport(renderer, &old.Viewport);
     SDL_RenderGetClipRect(renderer, &old.ClipRect);
 
+    // Setup desired state
+    ImGui_ImplSDLRenderer2_SetupRenderState(renderer);
+
+    // Setup render state structure (for callbacks and custom texture bindings)
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    ImGui_ImplSDLRenderer2_RenderState render_state;
+    render_state.Renderer = renderer;
+    platform_io.Renderer_RenderState = &render_state;
+
 	// Will project scissor/clipping rectangles into framebuffer space
 	ImVec2 clip_off = draw_data->DisplayPos;         // (0,0) unless using multi-viewports
 	ImVec2 clip_scale = render_scale;
 
     // Render command lists
-    ImGui_ImplSDLRenderer2_SetupRenderState(renderer);
     for (int n = 0; n < draw_data->CmdListsCount; n++)
     {
-        const ImDrawList* cmd_list = draw_data->CmdLists[n];
-        const ImDrawVert* vtx_buffer = cmd_list->VtxBuffer.Data;
-        const ImDrawIdx* idx_buffer = cmd_list->IdxBuffer.Data;
+        const ImDrawList* draw_list = draw_data->CmdLists[n];
+        const ImDrawVert* vtx_buffer = draw_list->VtxBuffer.Data;
+        const ImDrawIdx* idx_buffer = draw_list->IdxBuffer.Data;
 
-        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        for (int cmd_i = 0; cmd_i < draw_list->CmdBuffer.Size; cmd_i++)
         {
-            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            const ImDrawCmd* pcmd = &draw_list->CmdBuffer[cmd_i];
             if (pcmd->UserCallback)
             {
                 // User callback, registered via ImDrawList::AddCallback()
@@ -162,7 +174,7 @@ void ImGui_ImplSDLRenderer2_RenderDrawData(ImDrawData* draw_data, SDL_Renderer*
                 if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
                     ImGui_ImplSDLRenderer2_SetupRenderState(renderer);
                 else
-                    pcmd->UserCallback(cmd_list, pcmd);
+                    pcmd->UserCallback(draw_list, pcmd);
             }
             else
             {
@@ -193,11 +205,12 @@ void ImGui_ImplSDLRenderer2_RenderDrawData(ImDrawData* draw_data, SDL_Renderer*
                     xy, (int)sizeof(ImDrawVert),
                     color, (int)sizeof(ImDrawVert),
                     uv, (int)sizeof(ImDrawVert),
-                    cmd_list->VtxBuffer.Size - pcmd->VtxOffset,
+                    draw_list->VtxBuffer.Size - pcmd->VtxOffset,
                     idx_buffer + pcmd->IdxOffset, pcmd->ElemCount, sizeof(ImDrawIdx));
             }
         }
     }
+    platform_io.Renderer_RenderState = nullptr;
 
     // Restore modified SDL_Renderer state
     SDL_RenderSetViewport(renderer, &old.Viewport);

backends/imgui_impl_sdlrenderer2.h

@@ -9,7 +9,10 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'SDL_Texture*' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
+//  [X] Renderer: Expose selected render state for draw callbacks to use. Access in '(ImGui_ImplXXXX_RenderState*)GetPlatformIO().Renderer_RenderState'.
+// Missing features:
+//  [ ] Renderer: Multi-viewport support (multiple windows).
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -25,6 +28,7 @@
 
 struct SDL_Renderer;
 
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
 IMGUI_IMPL_API bool     ImGui_ImplSDLRenderer2_Init(SDL_Renderer* renderer);
 IMGUI_IMPL_API void     ImGui_ImplSDLRenderer2_Shutdown();
 IMGUI_IMPL_API void     ImGui_ImplSDLRenderer2_NewFrame();
@@ -36,4 +40,12 @@ IMGUI_IMPL_API void     ImGui_ImplSDLRenderer2_DestroyFontsTexture();
 IMGUI_IMPL_API bool     ImGui_ImplSDLRenderer2_CreateDeviceObjects();
 IMGUI_IMPL_API void     ImGui_ImplSDLRenderer2_DestroyDeviceObjects();
 
+// [BETA] Selected render state data shared with callbacks.
+// This is temporarily stored in GetPlatformIO().Renderer_RenderState during the ImGui_ImplSDLRenderer2_RenderDrawData() call.
+// (Please open an issue if you feel you need access to more data)
+struct ImGui_ImplSDLRenderer2_RenderState
+{
+    SDL_Renderer*       Renderer;
+};
+
 #endif // #ifndef IMGUI_DISABLE

backends/imgui_impl_sdlrenderer3.cpp

@@ -1,6 +1,8 @@
 // dear imgui: Renderer Backend for SDL_Renderer for SDL3
 // (Requires: SDL 3.0.0+)
 
+// (**IMPORTANT: SDL 3.0.0 is NOT YET RELEASED AND CURRENTLY HAS A FAST CHANGING API. THIS CODE BREAKS OFTEN AS SDL3 CHANGES.**)
+
 // Note how SDL_Renderer is an _optional_ component of SDL3.
 // For a multi-platform app consider using e.g. SDL+DirectX on Windows and SDL+OpenGL on Linux/OSX.
 // If your application will want to render any non trivial amount of graphics other than UI,
@@ -9,7 +11,10 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'SDL_Texture*' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
+//  [X] Renderer: Expose selected render state for draw callbacks to use. Access in '(ImGui_ImplXXXX_RenderState*)GetPlatformIO().Renderer_RenderState'.
+// Missing features:
+//  [ ] Renderer: Multi-viewport support (multiple windows).
 
 // You can copy and use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -20,6 +25,8 @@
 // - Introduction, links and more at the top of imgui.cpp
 
 // CHANGELOG
+//  2024-10-09: Expose selected render state in ImGui_ImplSDLRenderer3_RenderState, which you can access in 'void* platform_io.Renderer_RenderState' during draw callbacks.
+//  2024-07-01: Update for SDL3 api changes: SDL_RenderGeometryRaw() uint32 version was removed (SDL#9009).
 //  2024-05-14: *BREAKING CHANGE* ImGui_ImplSDLRenderer3_RenderDrawData() requires SDL_Renderer* passed as parameter.
 //  2024-02-12: Amend to query SDL_RenderViewportSet() and restore viewport accordingly.
 //  2023-05-30: Initial version.
@@ -44,8 +51,10 @@
 // SDL_Renderer data
 struct ImGui_ImplSDLRenderer3_Data
 {
-    SDL_Renderer*   Renderer;       // Main viewport's renderer
-    SDL_Texture*    FontTexture;
+    SDL_Renderer*           Renderer;       // Main viewport's renderer
+    SDL_Texture*            FontTexture;
+    ImVector<SDL_FColor>    ColorBuffer;
+
     ImGui_ImplSDLRenderer3_Data()   { memset((void*)this, 0, sizeof(*this)); }
 };
 
@@ -106,8 +115,28 @@ void ImGui_ImplSDLRenderer3_NewFrame()
         ImGui_ImplSDLRenderer3_CreateDeviceObjects();
 }
 
+// https://github.com/libsdl-org/SDL/issues/9009
+static int SDL_RenderGeometryRaw8BitColor(SDL_Renderer* renderer, ImVector<SDL_FColor>& colors_out, SDL_Texture* texture, const float* xy, int xy_stride, const SDL_Color* color, int color_stride, const float* uv, int uv_stride, int num_vertices, const void* indices, int num_indices, int size_indices)
+{
+    const Uint8* color2 = (const Uint8*)color;
+    colors_out.resize(num_vertices);
+    SDL_FColor* color3 = colors_out.Data;
+    for (int i = 0; i < num_vertices; i++)
+    {
+        color3[i].r = color->r / 255.0f;
+        color3[i].g = color->g / 255.0f;
+        color3[i].b = color->b / 255.0f;
+        color3[i].a = color->a / 255.0f;
+        color2 += color_stride;
+        color = (const SDL_Color*)color2;
+    }
+    return SDL_RenderGeometryRaw(renderer, texture, xy, xy_stride, color3, sizeof(*color3), uv, uv_stride, num_vertices, indices, num_indices, size_indices);
+}
+
 void ImGui_ImplSDLRenderer3_RenderDrawData(ImDrawData* draw_data, SDL_Renderer* renderer)
 {
+    ImGui_ImplSDLRenderer3_Data* bd = ImGui_ImplSDLRenderer3_GetBackendData();
+
 	// If there's a scale factor set by the user, use that instead
     // If the user has specified a scale factor to SDL_Renderer already via SDL_RenderSetScale(), SDL will scale whatever we pass
     // to SDL_RenderGeometryRaw() by that scale factor. In that case we don't want to be also scaling it ourselves here.
@@ -133,26 +162,34 @@ void ImGui_ImplSDLRenderer3_RenderDrawData(ImDrawData* draw_data, SDL_Renderer*
         SDL_Rect    ClipRect;
     };
     BackupSDLRendererState old = {};
-    old.ViewportEnabled = SDL_RenderViewportSet(renderer) == SDL_TRUE;
-    old.ClipEnabled = SDL_RenderClipEnabled(renderer) == SDL_TRUE;
+    old.ViewportEnabled = SDL_RenderViewportSet(renderer);
+    old.ClipEnabled = SDL_RenderClipEnabled(renderer);
     SDL_GetRenderViewport(renderer, &old.Viewport);
     SDL_GetRenderClipRect(renderer, &old.ClipRect);
 
+    // Setup desired state
+    ImGui_ImplSDLRenderer3_SetupRenderState(renderer);
+
+    // Setup render state structure (for callbacks and custom texture bindings)
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    ImGui_ImplSDLRenderer3_RenderState render_state;
+    render_state.Renderer = renderer;
+    platform_io.Renderer_RenderState = &render_state;
+
 	// Will project scissor/clipping rectangles into framebuffer space
 	ImVec2 clip_off = draw_data->DisplayPos;         // (0,0) unless using multi-viewports
 	ImVec2 clip_scale = render_scale;
 
     // Render command lists
-    ImGui_ImplSDLRenderer3_SetupRenderState(renderer);
     for (int n = 0; n < draw_data->CmdListsCount; n++)
     {
-        const ImDrawList* cmd_list = draw_data->CmdLists[n];
-        const ImDrawVert* vtx_buffer = cmd_list->VtxBuffer.Data;
-        const ImDrawIdx* idx_buffer = cmd_list->IdxBuffer.Data;
+        const ImDrawList* draw_list = draw_data->CmdLists[n];
+        const ImDrawVert* vtx_buffer = draw_list->VtxBuffer.Data;
+        const ImDrawIdx* idx_buffer = draw_list->IdxBuffer.Data;
 
-        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        for (int cmd_i = 0; cmd_i < draw_list->CmdBuffer.Size; cmd_i++)
         {
-            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            const ImDrawCmd* pcmd = &draw_list->CmdBuffer[cmd_i];
             if (pcmd->UserCallback)
             {
                 // User callback, registered via ImDrawList::AddCallback()
@@ -160,7 +197,7 @@ void ImGui_ImplSDLRenderer3_RenderDrawData(ImDrawData* draw_data, SDL_Renderer*
                 if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
                     ImGui_ImplSDLRenderer3_SetupRenderState(renderer);
                 else
-                    pcmd->UserCallback(cmd_list, pcmd);
+                    pcmd->UserCallback(draw_list, pcmd);
             }
             else
             {
@@ -183,15 +220,16 @@ void ImGui_ImplSDLRenderer3_RenderDrawData(ImDrawData* draw_data, SDL_Renderer*
 
                 // Bind texture, Draw
 				SDL_Texture* tex = (SDL_Texture*)pcmd->GetTexID();
-                SDL_RenderGeometryRaw(renderer, tex,
+                SDL_RenderGeometryRaw8BitColor(renderer, bd->ColorBuffer, tex,
                     xy, (int)sizeof(ImDrawVert),
                     color, (int)sizeof(ImDrawVert),
                     uv, (int)sizeof(ImDrawVert),
-                    cmd_list->VtxBuffer.Size - pcmd->VtxOffset,
+                    draw_list->VtxBuffer.Size - pcmd->VtxOffset,
                     idx_buffer + pcmd->IdxOffset, pcmd->ElemCount, sizeof(ImDrawIdx));
             }
         }
     }
+    platform_io.Renderer_RenderState = nullptr;
 
     // Restore modified SDL_Renderer state
     SDL_SetRenderViewport(renderer, old.ViewportEnabled ? &old.Viewport : nullptr);

backends/imgui_impl_sdlrenderer3.h

@@ -1,6 +1,8 @@
 // dear imgui: Renderer Backend for SDL_Renderer for SDL3
 // (Requires: SDL 3.0.0+)
 
+// (**IMPORTANT: SDL 3.0.0 is NOT YET RELEASED AND CURRENTLY HAS A FAST CHANGING API. THIS CODE BREAKS OFTEN AS SDL3 CHANGES.**)
+
 // Note how SDL_Renderer is an _optional_ component of SDL3.
 // For a multi-platform app consider using e.g. SDL+DirectX on Windows and SDL+OpenGL on Linux/OSX.
 // If your application will want to render any non trivial amount of graphics other than UI,
@@ -9,7 +11,10 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'SDL_Texture*' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
+//  [X] Renderer: Expose selected render state for draw callbacks to use. Access in '(ImGui_ImplXXXX_RenderState*)GetPlatformIO().Renderer_RenderState'.
+// Missing features:
+//  [ ] Renderer: Multi-viewport support (multiple windows).
 
 // You can copy and use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -25,6 +30,7 @@
 
 struct SDL_Renderer;
 
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
 IMGUI_IMPL_API bool     ImGui_ImplSDLRenderer3_Init(SDL_Renderer* renderer);
 IMGUI_IMPL_API void     ImGui_ImplSDLRenderer3_Shutdown();
 IMGUI_IMPL_API void     ImGui_ImplSDLRenderer3_NewFrame();
@@ -36,4 +42,12 @@ IMGUI_IMPL_API void     ImGui_ImplSDLRenderer3_DestroyFontsTexture();
 IMGUI_IMPL_API bool     ImGui_ImplSDLRenderer3_CreateDeviceObjects();
 IMGUI_IMPL_API void     ImGui_ImplSDLRenderer3_DestroyDeviceObjects();
 
+// [BETA] Selected render state data shared with callbacks.
+// This is temporarily stored in GetPlatformIO().Renderer_RenderState during the ImGui_ImplSDLRenderer3_RenderDrawData() call.
+// (Please open an issue if you feel you need access to more data)
+struct ImGui_ImplSDLRenderer3_RenderState
+{
+    SDL_Renderer*       Renderer;
+};
+
 #endif // #ifndef IMGUI_DISABLE

backends/imgui_impl_vulkan.cpp

@@ -2,16 +2,10 @@
 // This needs to be used along with a Platform Backend (e.g. GLFW, SDL, Win32, custom..)
 
 // Implemented features:
-//  [!] Renderer: User texture binding. Use 'VkDescriptorSet' as ImTextureID. Read the FAQ about ImTextureID! See https://github.com/ocornut/imgui/pull/914 for discussions.
-//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
-
-// Important: on 32-bit systems, user texture binding is only supported if your imconfig file has '#define ImTextureID ImU64'.
-// This is because we need ImTextureID to carry a 64-bit value and by default ImTextureID is defined as void*.
-// To build this on 32-bit systems and support texture changes:
-// - [Solution 1] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'ImTextureID=ImU64' (this is what we do in our .vcxproj files)
-// - [Solution 2] IDE/msbuild: in "Properties/C++/Preprocessor Definitions" add 'IMGUI_USER_CONFIG="my_imgui_config.h"' and inside 'my_imgui_config.h' add '#define ImTextureID ImU64' and as many other options as you like.
-// - [Solution 3] IDE/msbuild: edit imconfig.h and add '#define ImTextureID ImU64' (prefer solution 2 to create your own config file!)
-// - [Solution 4] command-line: add '/D ImTextureID=ImU64' to your cl.exe command-line (this is what we do in our batch files)
+//  [!] Renderer: User texture binding. Use 'VkDescriptorSet' as ImTextureID. Call ImGui_ImplVulkan_AddTexture() to register one. Read the FAQ about ImTextureID! See https://github.com/ocornut/imgui/pull/914 for discussions.
+//  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
+//  [X] Renderer: Expose selected render state for draw callbacks to use. Access in '(ImGui_ImplXXXX_RenderState*)GetPlatformIO().Renderer_RenderState'.
+//  [x] Renderer: Multi-viewport / platform windows. With issues (flickering when creating a new viewport).
 
 // The aim of imgui_impl_vulkan.h/.cpp is to be usable in your engine without any modification.
 // IF YOU FEEL YOU NEED TO MAKE ANY CHANGE TO THIS CODE, please share them and your feedback at https://github.com/ocornut/imgui/
@@ -33,6 +27,11 @@
 
 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
+//  2024-XX-XX: Platform: Added support for multiple windows via the ImGuiPlatformIO interface.
+//  2024-11-27: Vulkan: Make user-provided descriptor pool optional. As a convenience, when setting init_info->DescriptorPoolSize the backend will create one itself. (#8172, #4867)
+//  2024-10-07: Vulkan: Changed default texture sampler to Clamp instead of Repeat/Wrap.
+//  2024-10-07: Vulkan: Expose selected render state in ImGui_ImplVulkan_RenderState, which you can access in 'void* platform_io.Renderer_RenderState' during draw callbacks.
+//  2024-10-07: Vulkan: Compiling with '#define ImTextureID=ImU64' is unnecessary now that dear imgui defaults ImTextureID to u64 instead of void*.
 //  2024-04-19: Vulkan: Added convenience support for Volk via IMGUI_IMPL_VULKAN_USE_VOLK define (you can also use IMGUI_IMPL_VULKAN_NO_PROTOTYPES + wrap Volk via ImGui_ImplVulkan_LoadFunctions().)
 //  2024-02-14: *BREAKING CHANGE*: Moved RenderPass parameter from ImGui_ImplVulkan_Init() function to ImGui_ImplVulkan_InitInfo structure. Not required when using dynamic rendering.
 //  2024-02-12: *BREAKING CHANGE*: Dynamic rendering now require filling PipelineRenderingCreateInfo structure.
@@ -104,6 +103,7 @@ void ImGui_ImplVulkan_DestroyFrameRenderBuffers(VkDevice device, ImGui_ImplVulka
 void ImGui_ImplVulkan_DestroyWindowRenderBuffers(VkDevice device, ImGui_ImplVulkan_WindowRenderBuffers* buffers, const VkAllocationCallbacks* allocator);
 void ImGui_ImplVulkanH_DestroyFrame(VkDevice device, ImGui_ImplVulkanH_Frame* fd, const VkAllocationCallbacks* allocator);
 void ImGui_ImplVulkanH_DestroyFrameSemaphores(VkDevice device, ImGui_ImplVulkanH_FrameSemaphores* fsd, const VkAllocationCallbacks* allocator);
+void ImGui_ImplVulkanH_DestroyAllViewportsRenderBuffers(VkDevice device, const VkAllocationCallbacks* allocator);
 void ImGui_ImplVulkanH_CreateWindowSwapChain(VkPhysicalDevice physical_device, VkDevice device, ImGui_ImplVulkanH_Window* wd, const VkAllocationCallbacks* allocator, int w, int h, uint32_t min_image_count);
 void ImGui_ImplVulkanH_CreateWindowCommandBuffers(VkPhysicalDevice physical_device, VkDevice device, ImGui_ImplVulkanH_Window* wd, uint32_t queue_family, const VkAllocationCallbacks* allocator);
 
@@ -120,21 +120,25 @@ static bool g_FunctionsLoaded = true;
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkAllocateCommandBuffers) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkAllocateDescriptorSets) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkAllocateMemory) \
+    IMGUI_VULKAN_FUNC_MAP_MACRO(vkAcquireNextImageKHR) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkBeginCommandBuffer) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkBindBufferMemory) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkBindImageMemory) \
+    IMGUI_VULKAN_FUNC_MAP_MACRO(vkCmdBeginRenderPass) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkCmdBindDescriptorSets) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkCmdBindIndexBuffer) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkCmdBindPipeline) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkCmdBindVertexBuffers) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkCmdCopyBufferToImage) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkCmdDrawIndexed) \
+    IMGUI_VULKAN_FUNC_MAP_MACRO(vkCmdEndRenderPass) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkCmdPipelineBarrier) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkCmdPushConstants) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkCmdSetScissor) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkCmdSetViewport) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkCreateBuffer) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkCreateCommandPool) \
+    IMGUI_VULKAN_FUNC_MAP_MACRO(vkCreateDescriptorPool) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkCreateDescriptorSetLayout) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkCreateFence) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkCreateFramebuffer) \
@@ -149,6 +153,7 @@ static bool g_FunctionsLoaded = true;
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkCreateSwapchainKHR) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkDestroyBuffer) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkDestroyCommandPool) \
+    IMGUI_VULKAN_FUNC_MAP_MACRO(vkDestroyDescriptorPool) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkDestroyDescriptorSetLayout) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkDestroyFence) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkDestroyFramebuffer) \
@@ -174,13 +179,17 @@ static bool g_FunctionsLoaded = true;
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkGetPhysicalDeviceSurfaceCapabilitiesKHR) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkGetPhysicalDeviceSurfaceFormatsKHR) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkGetPhysicalDeviceSurfacePresentModesKHR) \
+    IMGUI_VULKAN_FUNC_MAP_MACRO(vkGetPhysicalDeviceSurfaceSupportKHR) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkGetSwapchainImagesKHR) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkMapMemory) \
+    IMGUI_VULKAN_FUNC_MAP_MACRO(vkQueuePresentKHR) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkQueueSubmit) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkQueueWaitIdle) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkResetCommandPool) \
+    IMGUI_VULKAN_FUNC_MAP_MACRO(vkResetFences) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkUnmapMemory) \
-    IMGUI_VULKAN_FUNC_MAP_MACRO(vkUpdateDescriptorSets)
+    IMGUI_VULKAN_FUNC_MAP_MACRO(vkUpdateDescriptorSets) \
+    IMGUI_VULKAN_FUNC_MAP_MACRO(vkWaitForFences)
 
 // Define function pointers
 #define IMGUI_VULKAN_FUNC_DEF(func) static PFN_##func func;
@@ -214,6 +223,29 @@ struct ImGui_ImplVulkan_WindowRenderBuffers
     ImGui_ImplVulkan_FrameRenderBuffers* FrameRenderBuffers;
 };
 
+struct ImGui_ImplVulkan_Texture
+{
+    VkDeviceMemory              Memory;
+    VkImage                     Image;
+    VkImageView                 ImageView;
+    VkDescriptorSet             DescriptorSet;
+
+    ImGui_ImplVulkan_Texture() { memset(this, 0, sizeof(*this)); }
+};
+
+// For multi-viewport support:
+// Helper structure we store in the void* RendererUserData field of each ImGuiViewport to easily retrieve our backend data.
+struct ImGui_ImplVulkan_ViewportData
+{
+    ImGui_ImplVulkanH_Window                Window;                 // Used by secondary viewports only
+    ImGui_ImplVulkan_WindowRenderBuffers    RenderBuffers;          // Used by all viewports
+    bool                                    WindowOwned;
+    bool                                    SwapChainNeedRebuild;   // Flag when viewport swapchain resized in the middle of processing a frame
+
+    ImGui_ImplVulkan_ViewportData() { WindowOwned = SwapChainNeedRebuild = false; memset(&RenderBuffers, 0, sizeof(RenderBuffers)); }
+    ~ImGui_ImplVulkan_ViewportData() { }
+};
+
 // Vulkan data
 struct ImGui_ImplVulkan_Data
 {
@@ -222,18 +254,17 @@ struct ImGui_ImplVulkan_Data
     VkPipelineCreateFlags       PipelineCreateFlags;
     VkDescriptorSetLayout       DescriptorSetLayout;
     VkPipelineLayout            PipelineLayout;
-    VkPipeline                  Pipeline;
+    VkPipeline                  Pipeline;               // pipeline for main render pass (created by app)
+    VkPipeline                  PipelineForViewports;   // pipeline for secondary viewports (created by backend)
     VkShaderModule              ShaderModuleVert;
     VkShaderModule              ShaderModuleFrag;
+    VkDescriptorPool            DescriptorPool;
 
-    // Font data
-    VkSampler                   FontSampler;
-    VkDeviceMemory              FontMemory;
-    VkImage                     FontImage;
-    VkImageView                 FontView;
-    VkDescriptorSet             FontDescriptorSet;
-    VkCommandPool               FontCommandPool;
-    VkCommandBuffer             FontCommandBuffer;
+    // Texture management
+    ImGui_ImplVulkan_Texture    FontTexture;
+    VkSampler                   TexSampler;
+    VkCommandPool               TexCommandPool;
+    VkCommandBuffer             TexCommandBuffer;
 
     // Render buffers for main window
     ImGui_ImplVulkan_WindowRenderBuffers MainWindowRenderBuffers;
@@ -249,6 +280,10 @@ struct ImGui_ImplVulkan_Data
 // SHADERS
 //-----------------------------------------------------------------------------
 
+// Forward Declarations
+static void ImGui_ImplVulkan_InitMultiViewportSupport();
+static void ImGui_ImplVulkan_ShutdownMultiViewportSupport();
+
 // backends/vulkan/glsl_shader.vert, compiled with:
 // # glslangValidator -V -x -o glsl_shader.vert.u32 glsl_shader.vert
 /*
@@ -394,7 +429,7 @@ static inline VkDeviceSize AlignBufferSize(VkDeviceSize size, VkDeviceSize align
     return (size + alignment - 1) & ~(alignment - 1);
 }
 
-static void CreateOrResizeBuffer(VkBuffer& buffer, VkDeviceMemory& buffer_memory, VkDeviceSize& buffer_size, size_t new_size, VkBufferUsageFlagBits usage)
+static void CreateOrResizeBuffer(VkBuffer& buffer, VkDeviceMemory& buffer_memory, VkDeviceSize& buffer_size, VkDeviceSize new_size, VkBufferUsageFlagBits usage)
 {
     ImGui_ImplVulkan_Data* bd = ImGui_ImplVulkan_GetBackendData();
     ImGui_ImplVulkan_InitInfo* v = &bd->VulkanInitInfo;
@@ -486,14 +521,16 @@ void ImGui_ImplVulkan_RenderDrawData(ImDrawData* draw_data, VkCommandBuffer comm
     if (pipeline == VK_NULL_HANDLE)
         pipeline = bd->Pipeline;
 
-    // Allocate array to store enough vertex/index buffers
-    ImGui_ImplVulkan_WindowRenderBuffers* wrb = &bd->MainWindowRenderBuffers;
+    // Allocate array to store enough vertex/index buffers. Each unique viewport gets its own storage.
+    ImGui_ImplVulkan_ViewportData* viewport_renderer_data = (ImGui_ImplVulkan_ViewportData*)draw_data->OwnerViewport->RendererUserData;
+    IM_ASSERT(viewport_renderer_data != nullptr);
+    ImGui_ImplVulkan_WindowRenderBuffers* wrb = &viewport_renderer_data->RenderBuffers;
     if (wrb->FrameRenderBuffers == nullptr)
     {
         wrb->Index = 0;
         wrb->Count = v->ImageCount;
         wrb->FrameRenderBuffers = (ImGui_ImplVulkan_FrameRenderBuffers*)IM_ALLOC(sizeof(ImGui_ImplVulkan_FrameRenderBuffers) * wrb->Count);
-        memset(wrb->FrameRenderBuffers, 0, sizeof(ImGui_ImplVulkan_FrameRenderBuffers) * wrb->Count);
+        memset((void*)wrb->FrameRenderBuffers, 0, sizeof(ImGui_ImplVulkan_FrameRenderBuffers) * wrb->Count);
     }
     IM_ASSERT(wrb->Count == v->ImageCount);
     wrb->Index = (wrb->Index + 1) % wrb->Count;
@@ -502,8 +539,8 @@ void ImGui_ImplVulkan_RenderDrawData(ImDrawData* draw_data, VkCommandBuffer comm
     if (draw_data->TotalVtxCount > 0)
     {
         // Create or resize the vertex/index buffers
-        size_t vertex_size = AlignBufferSize(draw_data->TotalVtxCount * sizeof(ImDrawVert), bd->BufferMemoryAlignment);
-        size_t index_size = AlignBufferSize(draw_data->TotalIdxCount * sizeof(ImDrawIdx), bd->BufferMemoryAlignment);
+        VkDeviceSize vertex_size = AlignBufferSize(draw_data->TotalVtxCount * sizeof(ImDrawVert), bd->BufferMemoryAlignment);
+        VkDeviceSize index_size = AlignBufferSize(draw_data->TotalIdxCount * sizeof(ImDrawIdx), bd->BufferMemoryAlignment);
         if (rb->VertexBuffer == VK_NULL_HANDLE || rb->VertexBufferSize < vertex_size)
             CreateOrResizeBuffer(rb->VertexBuffer, rb->VertexBufferMemory, rb->VertexBufferSize, vertex_size, VK_BUFFER_USAGE_VERTEX_BUFFER_BIT);
         if (rb->IndexBuffer == VK_NULL_HANDLE || rb->IndexBufferSize < index_size)
@@ -518,11 +555,11 @@ void ImGui_ImplVulkan_RenderDrawData(ImDrawData* draw_data, VkCommandBuffer comm
         check_vk_result(err);
         for (int n = 0; n < draw_data->CmdListsCount; n++)
         {
-            const ImDrawList* cmd_list = draw_data->CmdLists[n];
-            memcpy(vtx_dst, cmd_list->VtxBuffer.Data, cmd_list->VtxBuffer.Size * sizeof(ImDrawVert));
-            memcpy(idx_dst, cmd_list->IdxBuffer.Data, cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx));
-            vtx_dst += cmd_list->VtxBuffer.Size;
-            idx_dst += cmd_list->IdxBuffer.Size;
+            const ImDrawList* draw_list = draw_data->CmdLists[n];
+            memcpy(vtx_dst, draw_list->VtxBuffer.Data, draw_list->VtxBuffer.Size * sizeof(ImDrawVert));
+            memcpy(idx_dst, draw_list->IdxBuffer.Data, draw_list->IdxBuffer.Size * sizeof(ImDrawIdx));
+            vtx_dst += draw_list->VtxBuffer.Size;
+            idx_dst += draw_list->IdxBuffer.Size;
         }
         VkMappedMemoryRange range[2] = {};
         range[0].sType = VK_STRUCTURE_TYPE_MAPPED_MEMORY_RANGE;
@@ -540,6 +577,14 @@ void ImGui_ImplVulkan_RenderDrawData(ImDrawData* draw_data, VkCommandBuffer comm
     // Setup desired Vulkan state
     ImGui_ImplVulkan_SetupRenderState(draw_data, pipeline, command_buffer, rb, fb_width, fb_height);
 
+    // Setup render state structure (for callbacks and custom texture bindings)
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    ImGui_ImplVulkan_RenderState render_state;
+    render_state.CommandBuffer = command_buffer;
+    render_state.Pipeline = pipeline;
+    render_state.PipelineLayout = bd->PipelineLayout;
+    platform_io.Renderer_RenderState = &render_state;
+
     // Will project scissor/clipping rectangles into framebuffer space
     ImVec2 clip_off = draw_data->DisplayPos;         // (0,0) unless using multi-viewports
     ImVec2 clip_scale = draw_data->FramebufferScale; // (1,1) unless using retina display which are often (2,2)
@@ -550,10 +595,10 @@ void ImGui_ImplVulkan_RenderDrawData(ImDrawData* draw_data, VkCommandBuffer comm
     int global_idx_offset = 0;
     for (int n = 0; n < draw_data->CmdListsCount; n++)
     {
-        const ImDrawList* cmd_list = draw_data->CmdLists[n];
-        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        const ImDrawList* draw_list = draw_data->CmdLists[n];
+        for (int cmd_i = 0; cmd_i < draw_list->CmdBuffer.Size; cmd_i++)
         {
-            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            const ImDrawCmd* pcmd = &draw_list->CmdBuffer[cmd_i];
             if (pcmd->UserCallback != nullptr)
             {
                 // User callback, registered via ImDrawList::AddCallback()
@@ -561,7 +606,7 @@ void ImGui_ImplVulkan_RenderDrawData(ImDrawData* draw_data, VkCommandBuffer comm
                 if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
                     ImGui_ImplVulkan_SetupRenderState(draw_data, pipeline, command_buffer, rb, fb_width, fb_height);
                 else
-                    pcmd->UserCallback(cmd_list, pcmd);
+                    pcmd->UserCallback(draw_list, pcmd);
             }
             else
             {
@@ -586,22 +631,17 @@ void ImGui_ImplVulkan_RenderDrawData(ImDrawData* draw_data, VkCommandBuffer comm
                 vkCmdSetScissor(command_buffer, 0, 1, &scissor);
 
                 // Bind DescriptorSet with font or user texture
-                VkDescriptorSet desc_set[1] = { (VkDescriptorSet)pcmd->TextureId };
-                if (sizeof(ImTextureID) < sizeof(ImU64))
-                {
-                    // We don't support texture switches if ImTextureID hasn't been redefined to be 64-bit. Do a flaky check that other textures haven't been used.
-                    IM_ASSERT(pcmd->TextureId == (ImTextureID)bd->FontDescriptorSet);
-                    desc_set[0] = bd->FontDescriptorSet;
-                }
-                vkCmdBindDescriptorSets(command_buffer, VK_PIPELINE_BIND_POINT_GRAPHICS, bd->PipelineLayout, 0, 1, desc_set, 0, nullptr);
+                VkDescriptorSet desc_set = (VkDescriptorSet)pcmd->GetTexID();
+                vkCmdBindDescriptorSets(command_buffer, VK_PIPELINE_BIND_POINT_GRAPHICS, bd->PipelineLayout, 0, 1, &desc_set, 0, nullptr);
 
                 // Draw
                 vkCmdDrawIndexed(command_buffer, pcmd->ElemCount, 1, pcmd->IdxOffset + global_idx_offset, pcmd->VtxOffset + global_vtx_offset, 0);
             }
         }
-        global_idx_offset += cmd_list->IdxBuffer.Size;
-        global_vtx_offset += cmd_list->VtxBuffer.Size;
+        global_idx_offset += draw_list->IdxBuffer.Size;
+        global_vtx_offset += draw_list->VtxBuffer.Size;
     }
+    platform_io.Renderer_RenderState = nullptr;
 
     // Note: at this point both vkCmdSetViewport() and vkCmdSetScissor() have been called.
     // Our last values will leak into user/application rendering IF:
@@ -622,39 +662,39 @@ bool ImGui_ImplVulkan_CreateFontsTexture()
     VkResult err;
 
     // Destroy existing texture (if any)
-    if (bd->FontView || bd->FontImage || bd->FontMemory || bd->FontDescriptorSet)
+    if (bd->FontTexture.DescriptorSet)
     {
         vkQueueWaitIdle(v->Queue);
         ImGui_ImplVulkan_DestroyFontsTexture();
     }
 
     // Create command pool/buffer
-    if (bd->FontCommandPool == VK_NULL_HANDLE)
+    if (bd->TexCommandPool == VK_NULL_HANDLE)
     {
         VkCommandPoolCreateInfo info = {};
         info.sType = VK_STRUCTURE_TYPE_COMMAND_POOL_CREATE_INFO;
         info.flags = 0;
         info.queueFamilyIndex = v->QueueFamily;
-        vkCreateCommandPool(v->Device, &info, v->Allocator, &bd->FontCommandPool);
+        vkCreateCommandPool(v->Device, &info, v->Allocator, &bd->TexCommandPool);
     }
-    if (bd->FontCommandBuffer == VK_NULL_HANDLE)
+    if (bd->TexCommandBuffer == VK_NULL_HANDLE)
     {
         VkCommandBufferAllocateInfo info = {};
         info.sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_ALLOCATE_INFO;
-        info.commandPool = bd->FontCommandPool;
+        info.commandPool = bd->TexCommandPool;
         info.commandBufferCount = 1;
-        err = vkAllocateCommandBuffers(v->Device, &info, &bd->FontCommandBuffer);
+        err = vkAllocateCommandBuffers(v->Device, &info, &bd->TexCommandBuffer);
         check_vk_result(err);
     }
 
     // Start command buffer
     {
-        err = vkResetCommandPool(v->Device, bd->FontCommandPool, 0);
+        err = vkResetCommandPool(v->Device, bd->TexCommandPool, 0);
         check_vk_result(err);
         VkCommandBufferBeginInfo begin_info = {};
         begin_info.sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_BEGIN_INFO;
         begin_info.flags |= VK_COMMAND_BUFFER_USAGE_ONE_TIME_SUBMIT_BIT;
-        err = vkBeginCommandBuffer(bd->FontCommandBuffer, &begin_info);
+        err = vkBeginCommandBuffer(bd->TexCommandBuffer, &begin_info);
         check_vk_result(err);
     }
 
@@ -664,6 +704,7 @@ bool ImGui_ImplVulkan_CreateFontsTexture()
     size_t upload_size = width * height * 4 * sizeof(char);
 
     // Create the Image:
+    ImGui_ImplVulkan_Texture* backend_tex = &bd->FontTexture;
     {
         VkImageCreateInfo info = {};
         info.sType = VK_STRUCTURE_TYPE_IMAGE_CREATE_INFO;
@@ -679,17 +720,17 @@ bool ImGui_ImplVulkan_CreateFontsTexture()
         info.usage = VK_IMAGE_USAGE_SAMPLED_BIT | VK_IMAGE_USAGE_TRANSFER_DST_BIT;
         info.sharingMode = VK_SHARING_MODE_EXCLUSIVE;
         info.initialLayout = VK_IMAGE_LAYOUT_UNDEFINED;
-        err = vkCreateImage(v->Device, &info, v->Allocator, &bd->FontImage);
+        err = vkCreateImage(v->Device, &info, v->Allocator, &backend_tex->Image);
         check_vk_result(err);
         VkMemoryRequirements req;
-        vkGetImageMemoryRequirements(v->Device, bd->FontImage, &req);
+        vkGetImageMemoryRequirements(v->Device, backend_tex->Image, &req);
         VkMemoryAllocateInfo alloc_info = {};
         alloc_info.sType = VK_STRUCTURE_TYPE_MEMORY_ALLOCATE_INFO;
         alloc_info.allocationSize = IM_MAX(v->MinAllocationSize, req.size);
         alloc_info.memoryTypeIndex = ImGui_ImplVulkan_MemoryType(VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT, req.memoryTypeBits);
-        err = vkAllocateMemory(v->Device, &alloc_info, v->Allocator, &bd->FontMemory);
+        err = vkAllocateMemory(v->Device, &alloc_info, v->Allocator, &backend_tex->Memory);
         check_vk_result(err);
-        err = vkBindImageMemory(v->Device, bd->FontImage, bd->FontMemory, 0);
+        err = vkBindImageMemory(v->Device, backend_tex->Image, backend_tex->Memory, 0);
         check_vk_result(err);
     }
 
@@ -697,18 +738,18 @@ bool ImGui_ImplVulkan_CreateFontsTexture()
     {
         VkImageViewCreateInfo info = {};
         info.sType = VK_STRUCTURE_TYPE_IMAGE_VIEW_CREATE_INFO;
-        info.image = bd->FontImage;
+        info.image = backend_tex->Image;
         info.viewType = VK_IMAGE_VIEW_TYPE_2D;
         info.format = VK_FORMAT_R8G8B8A8_UNORM;
         info.subresourceRange.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
         info.subresourceRange.levelCount = 1;
         info.subresourceRange.layerCount = 1;
-        err = vkCreateImageView(v->Device, &info, v->Allocator, &bd->FontView);
+        err = vkCreateImageView(v->Device, &info, v->Allocator, &backend_tex->ImageView);
         check_vk_result(err);
     }
 
     // Create the Descriptor Set:
-    bd->FontDescriptorSet = (VkDescriptorSet)ImGui_ImplVulkan_AddTexture(bd->FontSampler, bd->FontView, VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL);
+    backend_tex->DescriptorSet = ImGui_ImplVulkan_AddTexture(bd->TexSampler, backend_tex->ImageView, VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL);
 
     // Create the Upload Buffer:
     VkDeviceMemory upload_buffer_memory;
@@ -758,11 +799,11 @@ bool ImGui_ImplVulkan_CreateFontsTexture()
         copy_barrier[0].newLayout = VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL;
         copy_barrier[0].srcQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED;
         copy_barrier[0].dstQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED;
-        copy_barrier[0].image = bd->FontImage;
+        copy_barrier[0].image = backend_tex->Image;
         copy_barrier[0].subresourceRange.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
         copy_barrier[0].subresourceRange.levelCount = 1;
         copy_barrier[0].subresourceRange.layerCount = 1;
-        vkCmdPipelineBarrier(bd->FontCommandBuffer, VK_PIPELINE_STAGE_HOST_BIT, VK_PIPELINE_STAGE_TRANSFER_BIT, 0, 0, nullptr, 0, nullptr, 1, copy_barrier);
+        vkCmdPipelineBarrier(bd->TexCommandBuffer, VK_PIPELINE_STAGE_HOST_BIT, VK_PIPELINE_STAGE_TRANSFER_BIT, 0, 0, nullptr, 0, nullptr, 1, copy_barrier);
 
         VkBufferImageCopy region = {};
         region.imageSubresource.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
@@ -770,7 +811,7 @@ bool ImGui_ImplVulkan_CreateFontsTexture()
         region.imageExtent.width = width;
         region.imageExtent.height = height;
         region.imageExtent.depth = 1;
-        vkCmdCopyBufferToImage(bd->FontCommandBuffer, upload_buffer, bd->FontImage, VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL, 1, &region);
+        vkCmdCopyBufferToImage(bd->TexCommandBuffer, upload_buffer, backend_tex->Image, VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL, 1, &region);
 
         VkImageMemoryBarrier use_barrier[1] = {};
         use_barrier[0].sType = VK_STRUCTURE_TYPE_IMAGE_MEMORY_BARRIER;
@@ -780,22 +821,22 @@ bool ImGui_ImplVulkan_CreateFontsTexture()
         use_barrier[0].newLayout = VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL;
         use_barrier[0].srcQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED;
         use_barrier[0].dstQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED;
-        use_barrier[0].image = bd->FontImage;
+        use_barrier[0].image = backend_tex->Image;
         use_barrier[0].subresourceRange.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
         use_barrier[0].subresourceRange.levelCount = 1;
         use_barrier[0].subresourceRange.layerCount = 1;
-        vkCmdPipelineBarrier(bd->FontCommandBuffer, VK_PIPELINE_STAGE_TRANSFER_BIT, VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT, 0, 0, nullptr, 0, nullptr, 1, use_barrier);
+        vkCmdPipelineBarrier(bd->TexCommandBuffer, VK_PIPELINE_STAGE_TRANSFER_BIT, VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT, 0, 0, nullptr, 0, nullptr, 1, use_barrier);
     }
 
     // Store our identifier
-    io.Fonts->SetTexID((ImTextureID)bd->FontDescriptorSet);
+    io.Fonts->SetTexID((ImTextureID)backend_tex->DescriptorSet);
 
     // End command buffer
     VkSubmitInfo end_info = {};
     end_info.sType = VK_STRUCTURE_TYPE_SUBMIT_INFO;
     end_info.commandBufferCount = 1;
-    end_info.pCommandBuffers = &bd->FontCommandBuffer;
-    err = vkEndCommandBuffer(bd->FontCommandBuffer);
+    end_info.pCommandBuffers = &bd->TexCommandBuffer;
+    err = vkEndCommandBuffer(bd->TexCommandBuffer);
     check_vk_result(err);
     err = vkQueueSubmit(v->Queue, 1, &end_info, VK_NULL_HANDLE);
     check_vk_result(err);
@@ -816,16 +857,17 @@ void ImGui_ImplVulkan_DestroyFontsTexture()
     ImGui_ImplVulkan_Data* bd = ImGui_ImplVulkan_GetBackendData();
     ImGui_ImplVulkan_InitInfo* v = &bd->VulkanInitInfo;
 
-    if (bd->FontDescriptorSet)
+    ImGui_ImplVulkan_Texture* backend_tex = &bd->FontTexture;
+
+    if (backend_tex->DescriptorSet)
     {
-        ImGui_ImplVulkan_RemoveTexture(bd->FontDescriptorSet);
-        bd->FontDescriptorSet = VK_NULL_HANDLE;
+        ImGui_ImplVulkan_RemoveTexture(backend_tex->DescriptorSet);
+        backend_tex->DescriptorSet = VK_NULL_HANDLE;
         io.Fonts->SetTexID(0);
     }
-
-    if (bd->FontView)   { vkDestroyImageView(v->Device, bd->FontView, v->Allocator); bd->FontView = VK_NULL_HANDLE; }
-    if (bd->FontImage)  { vkDestroyImage(v->Device, bd->FontImage, v->Allocator); bd->FontImage = VK_NULL_HANDLE; }
-    if (bd->FontMemory) { vkFreeMemory(v->Device, bd->FontMemory, v->Allocator); bd->FontMemory = VK_NULL_HANDLE; }
+    if (backend_tex->ImageView) { vkDestroyImageView(v->Device, backend_tex->ImageView, v->Allocator); backend_tex->ImageView = VK_NULL_HANDLE; }
+    if (backend_tex->Image)     { vkDestroyImage(v->Device, backend_tex->Image, v->Allocator); backend_tex->Image = VK_NULL_HANDLE; }
+    if (backend_tex->Memory)    { vkFreeMemory(v->Device, backend_tex->Memory, v->Allocator); backend_tex->Memory = VK_NULL_HANDLE; }
 }
 
 static void ImGui_ImplVulkan_CreateShaderModules(VkDevice device, const VkAllocationCallbacks* allocator)
@@ -957,7 +999,7 @@ static void ImGui_ImplVulkan_CreatePipeline(VkDevice device, const VkAllocationC
     if (bd->VulkanInitInfo.UseDynamicRendering)
     {
         IM_ASSERT(bd->VulkanInitInfo.PipelineRenderingCreateInfo.sType == VK_STRUCTURE_TYPE_PIPELINE_RENDERING_CREATE_INFO_KHR && "PipelineRenderingCreateInfo sType must be VK_STRUCTURE_TYPE_PIPELINE_RENDERING_CREATE_INFO_KHR");
-        IM_ASSERT(bd->VulkanInitInfo.PipelineRenderingCreateInfo.pNext == nullptr && "PipelineRenderingCreateInfo pNext must be NULL");
+        IM_ASSERT(bd->VulkanInitInfo.PipelineRenderingCreateInfo.pNext == nullptr && "PipelineRenderingCreateInfo pNext must be nullptr");
         info.pNext = &bd->VulkanInitInfo.PipelineRenderingCreateInfo;
         info.renderPass = VK_NULL_HANDLE; // Just make sure it's actually nullptr.
     }
@@ -973,7 +1015,7 @@ bool ImGui_ImplVulkan_CreateDeviceObjects()
     ImGui_ImplVulkan_InitInfo* v = &bd->VulkanInitInfo;
     VkResult err;
 
-    if (!bd->FontSampler)
+    if (!bd->TexSampler)
     {
         // Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling.
         VkSamplerCreateInfo info = {};
@@ -981,13 +1023,13 @@ bool ImGui_ImplVulkan_CreateDeviceObjects()
         info.magFilter = VK_FILTER_LINEAR;
         info.minFilter = VK_FILTER_LINEAR;
         info.mipmapMode = VK_SAMPLER_MIPMAP_MODE_LINEAR;
-        info.addressModeU = VK_SAMPLER_ADDRESS_MODE_REPEAT;
-        info.addressModeV = VK_SAMPLER_ADDRESS_MODE_REPEAT;
-        info.addressModeW = VK_SAMPLER_ADDRESS_MODE_REPEAT;
+        info.addressModeU = VK_SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE;
+        info.addressModeV = VK_SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE;
+        info.addressModeW = VK_SAMPLER_ADDRESS_MODE_CLAMP_TO_EDGE;
         info.minLod = -1000;
         info.maxLod = 1000;
         info.maxAnisotropy = 1.0f;
-        err = vkCreateSampler(v->Device, &info, v->Allocator, &bd->FontSampler);
+        err = vkCreateSampler(v->Device, &info, v->Allocator, &bd->TexSampler);
         check_vk_result(err);
     }
 
@@ -1005,6 +1047,20 @@ bool ImGui_ImplVulkan_CreateDeviceObjects()
         check_vk_result(err);
     }
 
+    if (v->DescriptorPoolSize)
+    {
+        VkDescriptorPoolSize pool_size = { VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, v->DescriptorPoolSize };
+        VkDescriptorPoolCreateInfo pool_info = {};
+        pool_info.sType = VK_STRUCTURE_TYPE_DESCRIPTOR_POOL_CREATE_INFO;
+        pool_info.flags = VK_DESCRIPTOR_POOL_CREATE_FREE_DESCRIPTOR_SET_BIT;
+        pool_info.maxSets = v->DescriptorPoolSize;
+        pool_info.poolSizeCount = 1;
+        pool_info.pPoolSizes = &pool_size;
+
+        err = vkCreateDescriptorPool(v->Device, &pool_info, v->Allocator, &bd->DescriptorPool);
+        check_vk_result(err);
+    }
+
     if (!bd->PipelineLayout)
     {
         // Constants: we are using 'vec2 offset' and 'vec2 scale' instead of a full 3d projection matrix
@@ -1032,17 +1088,19 @@ void    ImGui_ImplVulkan_DestroyDeviceObjects()
 {
     ImGui_ImplVulkan_Data* bd = ImGui_ImplVulkan_GetBackendData();
     ImGui_ImplVulkan_InitInfo* v = &bd->VulkanInitInfo;
-    ImGui_ImplVulkan_DestroyWindowRenderBuffers(v->Device, &bd->MainWindowRenderBuffers, v->Allocator);
+    ImGui_ImplVulkanH_DestroyAllViewportsRenderBuffers(v->Device, v->Allocator);
     ImGui_ImplVulkan_DestroyFontsTexture();
 
-    if (bd->FontCommandBuffer)    { vkFreeCommandBuffers(v->Device, bd->FontCommandPool, 1, &bd->FontCommandBuffer); bd->FontCommandBuffer = VK_NULL_HANDLE; }
-    if (bd->FontCommandPool)      { vkDestroyCommandPool(v->Device, bd->FontCommandPool, v->Allocator); bd->FontCommandPool = VK_NULL_HANDLE; }
+    if (bd->TexCommandBuffer)     { vkFreeCommandBuffers(v->Device, bd->TexCommandPool, 1, &bd->TexCommandBuffer); bd->TexCommandBuffer = VK_NULL_HANDLE; }
+    if (bd->TexCommandPool)       { vkDestroyCommandPool(v->Device, bd->TexCommandPool, v->Allocator); bd->TexCommandPool = VK_NULL_HANDLE; }
+    if (bd->TexSampler)           { vkDestroySampler(v->Device, bd->TexSampler, v->Allocator); bd->TexSampler = VK_NULL_HANDLE; }
     if (bd->ShaderModuleVert)     { vkDestroyShaderModule(v->Device, bd->ShaderModuleVert, v->Allocator); bd->ShaderModuleVert = VK_NULL_HANDLE; }
     if (bd->ShaderModuleFrag)     { vkDestroyShaderModule(v->Device, bd->ShaderModuleFrag, v->Allocator); bd->ShaderModuleFrag = VK_NULL_HANDLE; }
-    if (bd->FontSampler)          { vkDestroySampler(v->Device, bd->FontSampler, v->Allocator); bd->FontSampler = VK_NULL_HANDLE; }
     if (bd->DescriptorSetLayout)  { vkDestroyDescriptorSetLayout(v->Device, bd->DescriptorSetLayout, v->Allocator); bd->DescriptorSetLayout = VK_NULL_HANDLE; }
     if (bd->PipelineLayout)       { vkDestroyPipelineLayout(v->Device, bd->PipelineLayout, v->Allocator); bd->PipelineLayout = VK_NULL_HANDLE; }
     if (bd->Pipeline)             { vkDestroyPipeline(v->Device, bd->Pipeline, v->Allocator); bd->Pipeline = VK_NULL_HANDLE; }
+    if (bd->PipelineForViewports) { vkDestroyPipeline(v->Device, bd->PipelineForViewports, v->Allocator); bd->PipelineForViewports = VK_NULL_HANDLE; }
+    if (bd->DescriptorPool)       { vkDestroyDescriptorPool(v->Device, bd->DescriptorPool, v->Allocator); bd->DescriptorPool = VK_NULL_HANDLE; }
 }
 
 bool    ImGui_ImplVulkan_LoadFunctions(PFN_vkVoidFunction(*loader_func)(const char* function_name, void* user_data), void* user_data)
@@ -1100,12 +1158,16 @@ bool    ImGui_ImplVulkan_Init(ImGui_ImplVulkan_InitInfo* info)
     io.BackendRendererUserData = (void*)bd;
     io.BackendRendererName = "imgui_impl_vulkan";
     io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset;  // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
+    io.BackendFlags |= ImGuiBackendFlags_RendererHasViewports;  // We can create multi-viewports on the Renderer side (optional)
 
     IM_ASSERT(info->Instance != VK_NULL_HANDLE);
     IM_ASSERT(info->PhysicalDevice != VK_NULL_HANDLE);
     IM_ASSERT(info->Device != VK_NULL_HANDLE);
     IM_ASSERT(info->Queue != VK_NULL_HANDLE);
-    IM_ASSERT(info->DescriptorPool != VK_NULL_HANDLE);
+    if (info->DescriptorPool != VK_NULL_HANDLE) // Either DescriptorPool or DescriptorPoolSize must be set, not both!
+        IM_ASSERT(info->DescriptorPoolSize == 0);
+    else
+        IM_ASSERT(info->DescriptorPoolSize > 0);
     IM_ASSERT(info->MinImageCount >= 2);
     IM_ASSERT(info->ImageCount >= info->MinImageCount);
     if (info->UseDynamicRendering == false)
@@ -1115,6 +1177,12 @@ bool    ImGui_ImplVulkan_Init(ImGui_ImplVulkan_InitInfo* info)
 
     ImGui_ImplVulkan_CreateDeviceObjects();
 
+    // Our render function expect RendererUserData to be storing the window render buffer we need (for the main viewport we won't use ->Window)
+    ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+    main_viewport->RendererUserData = IM_NEW(ImGui_ImplVulkan_ViewportData)();
+
+    ImGui_ImplVulkan_InitMultiViewportSupport();
+
     return true;
 }
 
@@ -1124,10 +1192,21 @@ void ImGui_ImplVulkan_Shutdown()
     IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
     ImGuiIO& io = ImGui::GetIO();
 
+    // First destroy objects in all viewports
     ImGui_ImplVulkan_DestroyDeviceObjects();
+
+    // Manually delete main viewport render data in-case we haven't initialized for viewports
+    ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+    if (ImGui_ImplVulkan_ViewportData* vd = (ImGui_ImplVulkan_ViewportData*)main_viewport->RendererUserData)
+        IM_DELETE(vd);
+    main_viewport->RendererUserData = nullptr;
+
+    // Clean up windows
+    ImGui_ImplVulkan_ShutdownMultiViewportSupport();
+
     io.BackendRendererName = nullptr;
     io.BackendRendererUserData = nullptr;
-    io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset;
+    io.BackendFlags &= ~(ImGuiBackendFlags_RendererHasVtxOffset | ImGuiBackendFlags_RendererHasViewports);
     IM_DELETE(bd);
 }
 
@@ -1136,7 +1215,7 @@ void ImGui_ImplVulkan_NewFrame()
     ImGui_ImplVulkan_Data* bd = ImGui_ImplVulkan_GetBackendData();
     IM_ASSERT(bd != nullptr && "Context or backend not initialized! Did you call ImGui_ImplVulkan_Init()?");
 
-    if (!bd->FontDescriptorSet)
+    if (!bd->FontTexture.DescriptorSet)
         ImGui_ImplVulkan_CreateFontsTexture();
 }
 
@@ -1147,26 +1226,29 @@ void ImGui_ImplVulkan_SetMinImageCount(uint32_t min_image_count)
     if (bd->VulkanInitInfo.MinImageCount == min_image_count)
         return;
 
+    IM_ASSERT(0); // FIXME-VIEWPORT: Unsupported. Need to recreate all swap chains!
     ImGui_ImplVulkan_InitInfo* v = &bd->VulkanInitInfo;
     VkResult err = vkDeviceWaitIdle(v->Device);
     check_vk_result(err);
-    ImGui_ImplVulkan_DestroyWindowRenderBuffers(v->Device, &bd->MainWindowRenderBuffers, v->Allocator);
+    ImGui_ImplVulkanH_DestroyAllViewportsRenderBuffers(v->Device, v->Allocator);
+
     bd->VulkanInitInfo.MinImageCount = min_image_count;
 }
 
-// Register a texture
+// Register a texture by creating a descriptor
 // FIXME: This is experimental in the sense that we are unsure how to best design/tackle this problem, please post to https://github.com/ocornut/imgui/pull/914 if you have suggestions.
 VkDescriptorSet ImGui_ImplVulkan_AddTexture(VkSampler sampler, VkImageView image_view, VkImageLayout image_layout)
 {
     ImGui_ImplVulkan_Data* bd = ImGui_ImplVulkan_GetBackendData();
     ImGui_ImplVulkan_InitInfo* v = &bd->VulkanInitInfo;
+    VkDescriptorPool pool = bd->DescriptorPool ? bd->DescriptorPool : v->DescriptorPool;
 
     // Create Descriptor Set:
     VkDescriptorSet descriptor_set;
     {
         VkDescriptorSetAllocateInfo alloc_info = {};
         alloc_info.sType = VK_STRUCTURE_TYPE_DESCRIPTOR_SET_ALLOCATE_INFO;
-        alloc_info.descriptorPool = v->DescriptorPool;
+        alloc_info.descriptorPool = pool;
         alloc_info.descriptorSetCount = 1;
         alloc_info.pSetLayouts = &bd->DescriptorSetLayout;
         VkResult err = vkAllocateDescriptorSets(v->Device, &alloc_info, &descriptor_set);
@@ -1194,7 +1276,8 @@ void ImGui_ImplVulkan_RemoveTexture(VkDescriptorSet descriptor_set)
 {
     ImGui_ImplVulkan_Data* bd = ImGui_ImplVulkan_GetBackendData();
     ImGui_ImplVulkan_InitInfo* v = &bd->VulkanInitInfo;
-    vkFreeDescriptorSets(v->Device, v->DescriptorPool, 1, &descriptor_set);
+    VkDescriptorPool pool = bd->DescriptorPool ? bd->DescriptorPool : v->DescriptorPool;
+    vkFreeDescriptorSets(v->Device, pool, 1, &descriptor_set);
 }
 
 void ImGui_ImplVulkan_DestroyFrameRenderBuffers(VkDevice device, ImGui_ImplVulkan_FrameRenderBuffers* buffers, const VkAllocationCallbacks* allocator)
@@ -1385,8 +1468,6 @@ void ImGui_ImplVulkanH_CreateWindowSwapChain(VkPhysicalDevice physical_device, V
     wd->ImageCount = 0;
     if (wd->RenderPass)
         vkDestroyRenderPass(device, wd->RenderPass, allocator);
-    if (wd->Pipeline)
-        vkDestroyPipeline(device, wd->Pipeline, allocator);
 
     // If min image count was not specified, request different count of images dependent on selected present mode
     if (min_image_count == 0)
@@ -1440,8 +1521,8 @@ void ImGui_ImplVulkanH_CreateWindowSwapChain(VkPhysicalDevice physical_device, V
         wd->SemaphoreCount = wd->ImageCount + 1;
         wd->Frames = (ImGui_ImplVulkanH_Frame*)IM_ALLOC(sizeof(ImGui_ImplVulkanH_Frame) * wd->ImageCount);
         wd->FrameSemaphores = (ImGui_ImplVulkanH_FrameSemaphores*)IM_ALLOC(sizeof(ImGui_ImplVulkanH_FrameSemaphores) * wd->SemaphoreCount);
-        memset(wd->Frames, 0, sizeof(wd->Frames[0]) * wd->ImageCount);
-        memset(wd->FrameSemaphores, 0, sizeof(wd->FrameSemaphores[0]) * wd->SemaphoreCount);
+        memset((void*)wd->Frames, 0, sizeof(wd->Frames[0]) * wd->ImageCount);
+        memset((void*)wd->FrameSemaphores, 0, sizeof(wd->FrameSemaphores[0]) * wd->SemaphoreCount);
         for (uint32_t i = 0; i < wd->ImageCount; i++)
             wd->Frames[i].Backbuffer = backbuffers[i];
     }
@@ -1539,6 +1620,7 @@ void ImGui_ImplVulkanH_CreateOrResizeWindow(VkInstance instance, VkPhysicalDevic
     IM_ASSERT(g_FunctionsLoaded && "Need to call ImGui_ImplVulkan_LoadFunctions() if IMGUI_IMPL_VULKAN_NO_PROTOTYPES or VK_NO_PROTOTYPES are set!");
     (void)instance;
     ImGui_ImplVulkanH_CreateWindowSwapChain(physical_device, device, wd, allocator, width, height, min_image_count);
+    //ImGui_ImplVulkan_CreatePipeline(device, allocator, VK_NULL_HANDLE, wd->RenderPass, VK_SAMPLE_COUNT_1_BIT, &wd->Pipeline, g_VulkanInitInfo.Subpass);
     ImGui_ImplVulkanH_CreateWindowCommandBuffers(physical_device, device, wd, queue_family, allocator);
 }
 
@@ -1555,7 +1637,6 @@ void ImGui_ImplVulkanH_DestroyWindow(VkInstance instance, VkDevice device, ImGui
     IM_FREE(wd->FrameSemaphores);
     wd->Frames = nullptr;
     wd->FrameSemaphores = nullptr;
-    vkDestroyPipeline(device, wd->Pipeline, allocator);
     vkDestroyRenderPass(device, wd->RenderPass, allocator);
     vkDestroySwapchainKHR(device, wd->Swapchain, allocator);
     vkDestroySurfaceKHR(instance, wd->Surface, allocator);
@@ -1583,6 +1664,297 @@ void ImGui_ImplVulkanH_DestroyFrameSemaphores(VkDevice device, ImGui_ImplVulkanH
     fsd->ImageAcquiredSemaphore = fsd->RenderCompleteSemaphore = VK_NULL_HANDLE;
 }
 
+void ImGui_ImplVulkanH_DestroyAllViewportsRenderBuffers(VkDevice device, const VkAllocationCallbacks* allocator)
+{
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    for (int n = 0; n < platform_io.Viewports.Size; n++)
+        if (ImGui_ImplVulkan_ViewportData* vd = (ImGui_ImplVulkan_ViewportData*)platform_io.Viewports[n]->RendererUserData)
+            ImGui_ImplVulkan_DestroyWindowRenderBuffers(device, &vd->RenderBuffers, allocator);
+}
+
+//--------------------------------------------------------------------------------------------------------
+// MULTI-VIEWPORT / PLATFORM INTERFACE SUPPORT
+// This is an _advanced_ and _optional_ feature, allowing the backend to create and handle multiple viewports simultaneously.
+// If you are new to dear imgui or creating a new binding for dear imgui, it is recommended that you completely ignore this section first..
+//--------------------------------------------------------------------------------------------------------
+
+static void ImGui_ImplVulkan_CreateWindow(ImGuiViewport* viewport)
+{
+    ImGui_ImplVulkan_Data* bd = ImGui_ImplVulkan_GetBackendData();
+    ImGui_ImplVulkan_ViewportData* vd = IM_NEW(ImGui_ImplVulkan_ViewportData)();
+    viewport->RendererUserData = vd;
+    ImGui_ImplVulkanH_Window* wd = &vd->Window;
+    ImGui_ImplVulkan_InitInfo* v = &bd->VulkanInitInfo;
+
+    // Create surface
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    VkResult err = (VkResult)platform_io.Platform_CreateVkSurface(viewport, (ImU64)v->Instance, (const void*)v->Allocator, (ImU64*)&wd->Surface);
+    check_vk_result(err);
+
+    // Check for WSI support
+    VkBool32 res;
+    vkGetPhysicalDeviceSurfaceSupportKHR(v->PhysicalDevice, v->QueueFamily, wd->Surface, &res);
+    if (res != VK_TRUE)
+    {
+        IM_ASSERT(0); // Error: no WSI support on physical device
+        return;
+    }
+
+    // Select Surface Format
+    ImVector<VkFormat> requestSurfaceImageFormats;
+#ifdef IMGUI_IMPL_VULKAN_HAS_DYNAMIC_RENDERING
+    for (uint32_t n = 0; n < v->PipelineRenderingCreateInfo.colorAttachmentCount; n++)
+        requestSurfaceImageFormats.push_back(v->PipelineRenderingCreateInfo.pColorAttachmentFormats[n]);
+#endif
+    const VkFormat defaultFormats[] = { VK_FORMAT_B8G8R8A8_UNORM, VK_FORMAT_R8G8B8A8_UNORM, VK_FORMAT_B8G8R8_UNORM, VK_FORMAT_R8G8B8_UNORM };
+    for (VkFormat format : defaultFormats)
+        requestSurfaceImageFormats.push_back(format);
+
+    const VkColorSpaceKHR requestSurfaceColorSpace = VK_COLORSPACE_SRGB_NONLINEAR_KHR;
+    wd->SurfaceFormat = ImGui_ImplVulkanH_SelectSurfaceFormat(v->PhysicalDevice, wd->Surface, requestSurfaceImageFormats.Data, (size_t)requestSurfaceImageFormats.Size, requestSurfaceColorSpace);
+
+    // Select Present Mode
+    // FIXME-VULKAN: Even thought mailbox seems to get us maximum framerate with a single window, it halves framerate with a second window etc. (w/ Nvidia and SDK 1.82.1)
+    VkPresentModeKHR present_modes[] = { VK_PRESENT_MODE_MAILBOX_KHR, VK_PRESENT_MODE_IMMEDIATE_KHR, VK_PRESENT_MODE_FIFO_KHR };
+    wd->PresentMode = ImGui_ImplVulkanH_SelectPresentMode(v->PhysicalDevice, wd->Surface, &present_modes[0], IM_ARRAYSIZE(present_modes));
+    //printf("[vulkan] Secondary window selected PresentMode = %d\n", wd->PresentMode);
+
+    // Create SwapChain, RenderPass, Framebuffer, etc.
+    wd->ClearEnable = (viewport->Flags & ImGuiViewportFlags_NoRendererClear) ? false : true;
+    wd->UseDynamicRendering = v->UseDynamicRendering;
+    ImGui_ImplVulkanH_CreateOrResizeWindow(v->Instance, v->PhysicalDevice, v->Device, wd, v->QueueFamily, v->Allocator, (int)viewport->Size.x, (int)viewport->Size.y, v->MinImageCount);
+    vd->WindowOwned = true;
+
+    // Create pipeline (shared by all secondary viewports)
+    if (bd->PipelineForViewports == VK_NULL_HANDLE)
+        ImGui_ImplVulkan_CreatePipeline(v->Device, v->Allocator, VK_NULL_HANDLE, wd->RenderPass, VK_SAMPLE_COUNT_1_BIT, &bd->PipelineForViewports, 0);
+}
+
+static void ImGui_ImplVulkan_DestroyWindow(ImGuiViewport* viewport)
+{
+    // The main viewport (owned by the application) will always have RendererUserData == 0 since we didn't create the data for it.
+    ImGui_ImplVulkan_Data* bd = ImGui_ImplVulkan_GetBackendData();
+    if (ImGui_ImplVulkan_ViewportData* vd = (ImGui_ImplVulkan_ViewportData*)viewport->RendererUserData)
+    {
+        ImGui_ImplVulkan_InitInfo* v = &bd->VulkanInitInfo;
+        if (vd->WindowOwned)
+            ImGui_ImplVulkanH_DestroyWindow(v->Instance, v->Device, &vd->Window, v->Allocator);
+        ImGui_ImplVulkan_DestroyWindowRenderBuffers(v->Device, &vd->RenderBuffers, v->Allocator);
+        IM_DELETE(vd);
+    }
+    viewport->RendererUserData = nullptr;
+}
+
+static void ImGui_ImplVulkan_SetWindowSize(ImGuiViewport* viewport, ImVec2 size)
+{
+    ImGui_ImplVulkan_Data* bd = ImGui_ImplVulkan_GetBackendData();
+    ImGui_ImplVulkan_ViewportData* vd = (ImGui_ImplVulkan_ViewportData*)viewport->RendererUserData;
+    if (vd == nullptr) // This is nullptr for the main viewport (which is left to the user/app to handle)
+        return;
+    ImGui_ImplVulkan_InitInfo* v = &bd->VulkanInitInfo;
+    vd->Window.ClearEnable = (viewport->Flags & ImGuiViewportFlags_NoRendererClear) ? false : true;
+    ImGui_ImplVulkanH_CreateOrResizeWindow(v->Instance, v->PhysicalDevice, v->Device, &vd->Window, v->QueueFamily, v->Allocator, (int)size.x, (int)size.y, v->MinImageCount);
+}
+
+static void ImGui_ImplVulkan_RenderWindow(ImGuiViewport* viewport, void*)
+{
+    ImGui_ImplVulkan_Data* bd = ImGui_ImplVulkan_GetBackendData();
+    ImGui_ImplVulkan_ViewportData* vd = (ImGui_ImplVulkan_ViewportData*)viewport->RendererUserData;
+    ImGui_ImplVulkanH_Window* wd = &vd->Window;
+    ImGui_ImplVulkan_InitInfo* v = &bd->VulkanInitInfo;
+    VkResult err;
+
+    if (vd->SwapChainNeedRebuild)
+    {
+        ImGui_ImplVulkanH_CreateOrResizeWindow(v->Instance, v->PhysicalDevice, v->Device, wd, v->QueueFamily, v->Allocator, (int)viewport->Size.x, (int)viewport->Size.y, v->MinImageCount);
+        vd->SwapChainNeedRebuild = false;
+    }
+
+    ImGui_ImplVulkanH_Frame* fd = &wd->Frames[wd->FrameIndex];
+    ImGui_ImplVulkanH_FrameSemaphores* fsd = &wd->FrameSemaphores[wd->SemaphoreIndex];
+    {
+        {
+            err = vkAcquireNextImageKHR(v->Device, wd->Swapchain, UINT64_MAX, fsd->ImageAcquiredSemaphore, VK_NULL_HANDLE, &wd->FrameIndex);
+            if (err == VK_ERROR_OUT_OF_DATE_KHR)
+            {
+                // Since we are not going to swap this frame anyway, it's ok that recreation happens on next frame.
+                vd->SwapChainNeedRebuild = true;
+                return;
+            }
+            check_vk_result(err);
+            fd = &wd->Frames[wd->FrameIndex];
+        }
+        for (;;)
+        {
+            err = vkWaitForFences(v->Device, 1, &fd->Fence, VK_TRUE, 100);
+            if (err == VK_SUCCESS) break;
+            if (err == VK_TIMEOUT) continue;
+            check_vk_result(err);
+        }
+        {
+            err = vkResetCommandPool(v->Device, fd->CommandPool, 0);
+            check_vk_result(err);
+            VkCommandBufferBeginInfo info = {};
+            info.sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_BEGIN_INFO;
+            info.flags |= VK_COMMAND_BUFFER_USAGE_ONE_TIME_SUBMIT_BIT;
+            err = vkBeginCommandBuffer(fd->CommandBuffer, &info);
+            check_vk_result(err);
+        }
+        {
+            ImVec4 clear_color = ImVec4(0.0f, 0.0f, 0.0f, 1.0f);
+            memcpy(&wd->ClearValue.color.float32[0], &clear_color, 4 * sizeof(float));
+        }
+#ifdef IMGUI_IMPL_VULKAN_HAS_DYNAMIC_RENDERING
+        if (v->UseDynamicRendering)
+        {
+            // Transition swapchain image to a layout suitable for drawing.
+            VkImageMemoryBarrier barrier = {};
+            barrier.sType = VK_STRUCTURE_TYPE_IMAGE_MEMORY_BARRIER;
+            barrier.dstAccessMask = VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
+            barrier.oldLayout = VK_IMAGE_LAYOUT_UNDEFINED;
+            barrier.newLayout = VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL;
+            barrier.image = fd->Backbuffer;
+            barrier.subresourceRange.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
+            barrier.subresourceRange.levelCount = 1;
+            barrier.subresourceRange.layerCount = 1;
+            vkCmdPipelineBarrier(fd->CommandBuffer, VK_PIPELINE_STAGE_TOP_OF_PIPE_BIT, VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT, 0, 0, nullptr, 0, nullptr, 1, &barrier);
+
+            VkRenderingAttachmentInfo attachmentInfo = {};
+            attachmentInfo.sType = VK_STRUCTURE_TYPE_RENDERING_ATTACHMENT_INFO_KHR;
+            attachmentInfo.imageView = fd->BackbufferView;
+            attachmentInfo.imageLayout = VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL;
+            attachmentInfo.resolveMode = VK_RESOLVE_MODE_NONE;
+            attachmentInfo.loadOp = VK_ATTACHMENT_LOAD_OP_CLEAR;
+            attachmentInfo.storeOp = VK_ATTACHMENT_STORE_OP_STORE;
+            attachmentInfo.clearValue = wd->ClearValue;
+
+            VkRenderingInfo renderingInfo = {};
+            renderingInfo.sType = VK_STRUCTURE_TYPE_RENDERING_INFO_KHR;
+            renderingInfo.renderArea.extent.width = wd->Width;
+            renderingInfo.renderArea.extent.height = wd->Height;
+            renderingInfo.layerCount = 1;
+            renderingInfo.viewMask = 0;
+            renderingInfo.colorAttachmentCount = 1;
+            renderingInfo.pColorAttachments = &attachmentInfo;
+
+            ImGuiImplVulkanFuncs_vkCmdBeginRenderingKHR(fd->CommandBuffer, &renderingInfo);
+        }
+        else
+#endif
+        {
+            VkRenderPassBeginInfo info = {};
+            info.sType = VK_STRUCTURE_TYPE_RENDER_PASS_BEGIN_INFO;
+            info.renderPass = wd->RenderPass;
+            info.framebuffer = fd->Framebuffer;
+            info.renderArea.extent.width = wd->Width;
+            info.renderArea.extent.height = wd->Height;
+            info.clearValueCount = (viewport->Flags & ImGuiViewportFlags_NoRendererClear) ? 0 : 1;
+            info.pClearValues = (viewport->Flags & ImGuiViewportFlags_NoRendererClear) ? nullptr : &wd->ClearValue;
+            vkCmdBeginRenderPass(fd->CommandBuffer, &info, VK_SUBPASS_CONTENTS_INLINE);
+        }
+    }
+
+    ImGui_ImplVulkan_RenderDrawData(viewport->DrawData, fd->CommandBuffer, bd->PipelineForViewports);
+
+    {
+#ifdef IMGUI_IMPL_VULKAN_HAS_DYNAMIC_RENDERING
+        if (v->UseDynamicRendering)
+        {
+            ImGuiImplVulkanFuncs_vkCmdEndRenderingKHR(fd->CommandBuffer);
+
+            // Transition image to a layout suitable for presentation
+            VkImageMemoryBarrier barrier = {};
+            barrier.sType = VK_STRUCTURE_TYPE_IMAGE_MEMORY_BARRIER;
+            barrier.srcAccessMask = VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
+            barrier.oldLayout = VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL;
+            barrier.newLayout = VK_IMAGE_LAYOUT_PRESENT_SRC_KHR;
+            barrier.image = fd->Backbuffer;
+            barrier.subresourceRange.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
+            barrier.subresourceRange.levelCount = 1;
+            barrier.subresourceRange.layerCount = 1;
+            vkCmdPipelineBarrier(fd->CommandBuffer, VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT, VK_PIPELINE_STAGE_BOTTOM_OF_PIPE_BIT, 0, 0, nullptr, 0, nullptr, 1, &barrier);
+        }
+        else
+#endif
+        {
+            vkCmdEndRenderPass(fd->CommandBuffer);
+        }
+        {
+            VkPipelineStageFlags wait_stage = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT;
+            VkSubmitInfo info = {};
+            info.sType = VK_STRUCTURE_TYPE_SUBMIT_INFO;
+            info.waitSemaphoreCount = 1;
+            info.pWaitSemaphores = &fsd->ImageAcquiredSemaphore;
+            info.pWaitDstStageMask = &wait_stage;
+            info.commandBufferCount = 1;
+            info.pCommandBuffers = &fd->CommandBuffer;
+            info.signalSemaphoreCount = 1;
+            info.pSignalSemaphores = &fsd->RenderCompleteSemaphore;
+
+            err = vkEndCommandBuffer(fd->CommandBuffer);
+            check_vk_result(err);
+            err = vkResetFences(v->Device, 1, &fd->Fence);
+            check_vk_result(err);
+            err = vkQueueSubmit(v->Queue, 1, &info, fd->Fence);
+            check_vk_result(err);
+        }
+    }
+}
+
+static void ImGui_ImplVulkan_SwapBuffers(ImGuiViewport* viewport, void*)
+{
+    ImGui_ImplVulkan_Data* bd = ImGui_ImplVulkan_GetBackendData();
+    ImGui_ImplVulkan_ViewportData* vd = (ImGui_ImplVulkan_ViewportData*)viewport->RendererUserData;
+    ImGui_ImplVulkanH_Window* wd = &vd->Window;
+    ImGui_ImplVulkan_InitInfo* v = &bd->VulkanInitInfo;
+
+    if (vd->SwapChainNeedRebuild) // Frame data became invalid in the middle of rendering
+        return;
+
+    VkResult err;
+    uint32_t present_index = wd->FrameIndex;
+
+    ImGui_ImplVulkanH_FrameSemaphores* fsd = &wd->FrameSemaphores[wd->SemaphoreIndex];
+    VkPresentInfoKHR info = {};
+    info.sType = VK_STRUCTURE_TYPE_PRESENT_INFO_KHR;
+    info.waitSemaphoreCount = 1;
+    info.pWaitSemaphores = &fsd->RenderCompleteSemaphore;
+    info.swapchainCount = 1;
+    info.pSwapchains = &wd->Swapchain;
+    info.pImageIndices = &present_index;
+    err = vkQueuePresentKHR(v->Queue, &info);
+    if (err == VK_ERROR_OUT_OF_DATE_KHR || err == VK_SUBOPTIMAL_KHR)
+    {
+        vd->SwapChainNeedRebuild = true;
+        if (err == VK_ERROR_OUT_OF_DATE_KHR)
+            return;
+    }
+    else
+    {
+        check_vk_result(err);
+    }
+
+    wd->FrameIndex = (wd->FrameIndex + 1) % wd->ImageCount;             // This is for the next vkWaitForFences()
+    wd->SemaphoreIndex = (wd->SemaphoreIndex + 1) % wd->SemaphoreCount; // Now we can use the next set of semaphores
+}
+
+void ImGui_ImplVulkan_InitMultiViewportSupport()
+{
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    if (ImGui::GetIO().ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+        IM_ASSERT(platform_io.Platform_CreateVkSurface != nullptr && "Platform needs to setup the CreateVkSurface handler.");
+    platform_io.Renderer_CreateWindow = ImGui_ImplVulkan_CreateWindow;
+    platform_io.Renderer_DestroyWindow = ImGui_ImplVulkan_DestroyWindow;
+    platform_io.Renderer_SetWindowSize = ImGui_ImplVulkan_SetWindowSize;
+    platform_io.Renderer_RenderWindow = ImGui_ImplVulkan_RenderWindow;
+    platform_io.Renderer_SwapBuffers = ImGui_ImplVulkan_SwapBuffers;
+}
+
+void ImGui_ImplVulkan_ShutdownMultiViewportSupport()
+{
+    ImGui::DestroyPlatformWindows();
+}
+
 //-----------------------------------------------------------------------------
 
 #endif // #ifndef IMGUI_DISABLE

backends/imgui_impl_vulkan.h

@@ -2,11 +2,10 @@
 // This needs to be used along with a Platform Backend (e.g. GLFW, SDL, Win32, custom..)
 
 // Implemented features:
-//  [!] Renderer: User texture binding. Use 'VkDescriptorSet' as ImTextureID. Read the FAQ about ImTextureID! See https://github.com/ocornut/imgui/pull/914 for discussions.
-//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
-
-// Important: on 32-bit systems, user texture binding is only supported if your imconfig file has '#define ImTextureID ImU64'.
-// See imgui_impl_vulkan.cpp file for details.
+//  [!] Renderer: User texture binding. Use 'VkDescriptorSet' as ImTextureID. Call ImGui_ImplVulkan_AddTexture() to register one. Read the FAQ about ImTextureID! See https://github.com/ocornut/imgui/pull/914 for discussions.
+//  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
+//  [X] Renderer: Expose selected render state for draw callbacks to use. Access in '(ImGui_ImplXXXX_RenderState*)GetPlatformIO().Renderer_RenderState'.
+//  [x] Renderer: Multi-viewport / platform windows. With issues (flickering when creating a new viewport).
 
 // The aim of imgui_impl_vulkan.h/.cpp is to be usable in your engine without any modification.
 // IF YOU FEEL YOU NEED TO MAKE ANY CHANGE TO THIS CODE, please share them and your feedback at https://github.com/ocornut/imgui/
@@ -55,7 +54,7 @@
 
 // Vulkan includes
 #ifdef IMGUI_IMPL_VULKAN_USE_VOLK
-#include <Volk/volk.h>
+#include <volk.h>
 #else
 #include <vulkan/vulkan.h>
 #endif
@@ -64,10 +63,15 @@
 #endif
 
 // Initialization data, for ImGui_ImplVulkan_Init()
-// - VkDescriptorPool should be created with VK_DESCRIPTOR_POOL_CREATE_FREE_DESCRIPTOR_SET_BIT,
-//   and must contain a pool size large enough to hold an ImGui VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER descriptor.
-// - When using dynamic rendering, set UseDynamicRendering=true and fill PipelineRenderingCreateInfo structure.
 // [Please zero-clear before use!]
+// - About descriptor pool:
+//   - A VkDescriptorPool should be created with VK_DESCRIPTOR_POOL_CREATE_FREE_DESCRIPTOR_SET_BIT,
+//     and must contain a pool size large enough to hold a small number of VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER descriptors.
+//   - As an convenience, by setting DescriptorPoolSize > 0 the backend will create one for you.
+//   - Current version of the backend use 1 descriptor for the font atlas + as many as additional calls done to ImGui_ImplVulkan_AddTexture().
+//   - It is expected that as early as Q1 2025 the backend will use a few more descriptors, so aim at 10 + number of desierd calls to ImGui_ImplVulkan_AddTexture().
+// - About dynamic rendering:
+//   - When using dynamic rendering, set UseDynamicRendering=true and fill PipelineRenderingCreateInfo structure.
 struct ImGui_ImplVulkan_InitInfo
 {
     VkInstance                      Instance;
@@ -75,7 +79,7 @@ struct ImGui_ImplVulkan_InitInfo
     VkDevice                        Device;
     uint32_t                        QueueFamily;
     VkQueue                         Queue;
-    VkDescriptorPool                DescriptorPool;               // See requirements in note above
+    VkDescriptorPool                DescriptorPool;               // See requirements in note above; ignored if using DescriptorPoolSize > 0
     VkRenderPass                    RenderPass;                   // Ignored if using dynamic rendering
     uint32_t                        MinImageCount;                // >= 2
     uint32_t                        ImageCount;                   // >= MinImageCount
@@ -85,6 +89,9 @@ struct ImGui_ImplVulkan_InitInfo
     VkPipelineCache                 PipelineCache;
     uint32_t                        Subpass;
 
+    // (Optional) Set to create internal descriptor pool instead of using DescriptorPool
+    uint32_t                        DescriptorPoolSize;
+
     // (Optional) Dynamic Rendering
     // Need to explicitly enable VK_KHR_dynamic_rendering extension to use this, even for Vulkan 1.3.
     bool                            UseDynamicRendering;
@@ -98,24 +105,34 @@ struct ImGui_ImplVulkan_InitInfo
     VkDeviceSize                    MinAllocationSize;      // Minimum allocation size. Set to 1024*1024 to satisfy zealous best practices validation layer and waste a little memory.
 };
 
-// Called by user code
-IMGUI_IMPL_API bool         ImGui_ImplVulkan_Init(ImGui_ImplVulkan_InitInfo* info);
-IMGUI_IMPL_API void         ImGui_ImplVulkan_Shutdown();
-IMGUI_IMPL_API void         ImGui_ImplVulkan_NewFrame();
-IMGUI_IMPL_API void         ImGui_ImplVulkan_RenderDrawData(ImDrawData* draw_data, VkCommandBuffer command_buffer, VkPipeline pipeline = VK_NULL_HANDLE);
-IMGUI_IMPL_API bool         ImGui_ImplVulkan_CreateFontsTexture();
-IMGUI_IMPL_API void         ImGui_ImplVulkan_DestroyFontsTexture();
-IMGUI_IMPL_API void         ImGui_ImplVulkan_SetMinImageCount(uint32_t min_image_count); // To override MinImageCount after initialization (e.g. if swap chain is recreated)
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
+IMGUI_IMPL_API bool             ImGui_ImplVulkan_Init(ImGui_ImplVulkan_InitInfo* info);
+IMGUI_IMPL_API void             ImGui_ImplVulkan_Shutdown();
+IMGUI_IMPL_API void             ImGui_ImplVulkan_NewFrame();
+IMGUI_IMPL_API void             ImGui_ImplVulkan_RenderDrawData(ImDrawData* draw_data, VkCommandBuffer command_buffer, VkPipeline pipeline = VK_NULL_HANDLE);
+IMGUI_IMPL_API bool             ImGui_ImplVulkan_CreateFontsTexture();
+IMGUI_IMPL_API void             ImGui_ImplVulkan_DestroyFontsTexture();
+IMGUI_IMPL_API void             ImGui_ImplVulkan_SetMinImageCount(uint32_t min_image_count); // To override MinImageCount after initialization (e.g. if swap chain is recreated)
 
 // Register a texture (VkDescriptorSet == ImTextureID)
 // FIXME: This is experimental in the sense that we are unsure how to best design/tackle this problem
 // Please post to https://github.com/ocornut/imgui/pull/914 if you have suggestions.
-IMGUI_IMPL_API VkDescriptorSet ImGui_ImplVulkan_AddTexture(VkSampler sampler, VkImageView image_view, VkImageLayout image_layout);
-IMGUI_IMPL_API void            ImGui_ImplVulkan_RemoveTexture(VkDescriptorSet descriptor_set);
+IMGUI_IMPL_API VkDescriptorSet  ImGui_ImplVulkan_AddTexture(VkSampler sampler, VkImageView image_view, VkImageLayout image_layout);
+IMGUI_IMPL_API void             ImGui_ImplVulkan_RemoveTexture(VkDescriptorSet descriptor_set);
 
 // Optional: load Vulkan functions with a custom function loader
 // This is only useful with IMGUI_IMPL_VULKAN_NO_PROTOTYPES / VK_NO_PROTOTYPES
-IMGUI_IMPL_API bool         ImGui_ImplVulkan_LoadFunctions(PFN_vkVoidFunction(*loader_func)(const char* function_name, void* user_data), void* user_data = nullptr);
+IMGUI_IMPL_API bool             ImGui_ImplVulkan_LoadFunctions(PFN_vkVoidFunction(*loader_func)(const char* function_name, void* user_data), void* user_data = nullptr);
+
+// [BETA] Selected render state data shared with callbacks.
+// This is temporarily stored in GetPlatformIO().Renderer_RenderState during the ImGui_ImplVulkan_RenderDrawData() call.
+// (Please open an issue if you feel you need access to more data)
+struct ImGui_ImplVulkan_RenderState
+{
+    VkCommandBuffer     CommandBuffer;
+    VkPipeline          Pipeline;
+    VkPipelineLayout    PipelineLayout;
+};
 
 //-------------------------------------------------------------------------
 // Internal / Miscellaneous Vulkan Helpers
@@ -137,8 +154,8 @@ struct ImGui_ImplVulkanH_Frame;
 struct ImGui_ImplVulkanH_Window;
 
 // Helpers
-IMGUI_IMPL_API void                 ImGui_ImplVulkanH_CreateOrResizeWindow(VkInstance instance, VkPhysicalDevice physical_device, VkDevice device, ImGui_ImplVulkanH_Window* wnd, uint32_t queue_family, const VkAllocationCallbacks* allocator, int w, int h, uint32_t min_image_count);
-IMGUI_IMPL_API void                 ImGui_ImplVulkanH_DestroyWindow(VkInstance instance, VkDevice device, ImGui_ImplVulkanH_Window* wnd, const VkAllocationCallbacks* allocator);
+IMGUI_IMPL_API void                 ImGui_ImplVulkanH_CreateOrResizeWindow(VkInstance instance, VkPhysicalDevice physical_device, VkDevice device, ImGui_ImplVulkanH_Window* wd, uint32_t queue_family, const VkAllocationCallbacks* allocator, int w, int h, uint32_t min_image_count);
+IMGUI_IMPL_API void                 ImGui_ImplVulkanH_DestroyWindow(VkInstance instance, VkDevice device, ImGui_ImplVulkanH_Window* wd, const VkAllocationCallbacks* allocator);
 IMGUI_IMPL_API VkSurfaceFormatKHR   ImGui_ImplVulkanH_SelectSurfaceFormat(VkPhysicalDevice physical_device, VkSurfaceKHR surface, const VkFormat* request_formats, int request_formats_count, VkColorSpaceKHR request_color_space);
 IMGUI_IMPL_API VkPresentModeKHR     ImGui_ImplVulkanH_SelectPresentMode(VkPhysicalDevice physical_device, VkSurfaceKHR surface, const VkPresentModeKHR* request_modes, int request_modes_count);
 IMGUI_IMPL_API int                  ImGui_ImplVulkanH_GetMinImageCountFromPresentMode(VkPresentModeKHR present_mode);
@@ -173,7 +190,6 @@ struct ImGui_ImplVulkanH_Window
     VkSurfaceFormatKHR  SurfaceFormat;
     VkPresentModeKHR    PresentMode;
     VkRenderPass        RenderPass;
-    VkPipeline          Pipeline;               // The window pipeline may uses a different VkRenderPass than the one passed in ImGui_ImplVulkan_InitInfo
     bool                UseDynamicRendering;
     bool                ClearEnable;
     VkClearValue        ClearValue;

backends/imgui_impl_wgpu.cpp

@@ -4,7 +4,10 @@
 
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'WGPUTextureView' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
+//  [X] Renderer: Expose selected render state for draw callbacks to use. Access in '(ImGui_ImplXXXX_RenderState*)GetPlatformIO().Renderer_RenderState'.
+// Missing features:
+//  [ ] Renderer: Multi-viewport support (multiple windows). Not meaningful on the web.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -16,6 +19,10 @@
 
 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
+//  2024-10-14: Update Dawn support for change of string usages. (#8082, #8083)
+//  2024-10-07: Expose selected render state in ImGui_ImplWGPU_RenderState, which you can access in 'void* platform_io.Renderer_RenderState' during draw callbacks.
+//  2024-10-07: Changed default texture sampler to Clamp instead of Repeat/Wrap.
+//  2024-09-16: Added support for optional IMGUI_IMPL_WEBGPU_BACKEND_DAWN / IMGUI_IMPL_WEBGPU_BACKEND_WGPU define to handle ever-changing native implementations. (#7977)
 //  2024-01-22: Added configurable PipelineMultisampleState struct. (#7240)
 //  2024-01-22: (Breaking) ImGui_ImplWGPU_Init() now takes a ImGui_ImplWGPU_InitInfo structure instead of variety of parameters, allowing for easier further changes.
 //  2024-01-22: Fixed pipeline layout leak. (#7245)
@@ -35,6 +42,18 @@
 //  2021-02-18: Change blending equation to preserve alpha in output buffer.
 //  2021-01-28: Initial version.
 
+// When targeting native platforms (i.e. NOT emscripten), one of IMGUI_IMPL_WEBGPU_BACKEND_DAWN
+// or IMGUI_IMPL_WEBGPU_BACKEND_WGPU must be provided. See imgui_impl_wgpu.h for more details.
+#ifndef __EMSCRIPTEN__
+    #if defined(IMGUI_IMPL_WEBGPU_BACKEND_DAWN) == defined(IMGUI_IMPL_WEBGPU_BACKEND_WGPU)
+    #error exactly one of IMGUI_IMPL_WEBGPU_BACKEND_DAWN or IMGUI_IMPL_WEBGPU_BACKEND_WGPU must be defined!
+    #endif
+#else
+    #if defined(IMGUI_IMPL_WEBGPU_BACKEND_DAWN) || defined(IMGUI_IMPL_WEBGPU_BACKEND_WGPU)
+    #error neither IMGUI_IMPL_WEBGPU_BACKEND_DAWN nor IMGUI_IMPL_WEBGPU_BACKEND_WGPU may be defined if targeting emscripten!
+    #endif
+#endif
+
 #include "imgui.h"
 #ifndef IMGUI_DISABLE
 #include "imgui_impl_wgpu.h"
@@ -244,16 +263,26 @@ static WGPUProgrammableStageDescriptor ImGui_ImplWGPU_CreateShaderModule(const c
 {
     ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData();
 
-    WGPUShaderModuleWGSLDescriptor wgsl_desc = {};
+#ifdef IMGUI_IMPL_WEBGPU_BACKEND_DAWN
+	WGPUShaderSourceWGSL wgsl_desc = {};
+    wgsl_desc.chain.sType = WGPUSType_ShaderSourceWGSL;
+	wgsl_desc.code = { wgsl_source, WGPU_STRLEN };
+#else
+	WGPUShaderModuleWGSLDescriptor wgsl_desc = {};
     wgsl_desc.chain.sType = WGPUSType_ShaderModuleWGSLDescriptor;
-    wgsl_desc.code = wgsl_source;
+	wgsl_desc.code = wgsl_source;
+#endif
 
     WGPUShaderModuleDescriptor desc = {};
     desc.nextInChain = reinterpret_cast<WGPUChainedStruct*>(&wgsl_desc);
 
     WGPUProgrammableStageDescriptor stage_desc = {};
     stage_desc.module = wgpuDeviceCreateShaderModule(bd->wgpuDevice, &desc);
+#ifdef IMGUI_IMPL_WEBGPU_BACKEND_DAWN
+    stage_desc.entryPoint = { "main", WGPU_STRLEN };
+#else
     stage_desc.entryPoint = "main";
+#endif
     return stage_desc;
 }
 
@@ -366,6 +395,9 @@ void ImGui_ImplWGPU_RenderDrawData(ImDrawData* draw_data, WGPURenderPassEncoder
         {
             nullptr,
             "Dear ImGui Vertex buffer",
+#ifdef IMGUI_IMPL_WEBGPU_BACKEND_DAWN
+            WGPU_STRLEN,
+#endif
             WGPUBufferUsage_CopyDst | WGPUBufferUsage_Vertex,
             MEMALIGN(fr->VertexBufferSize * sizeof(ImDrawVert), 4),
             false
@@ -390,6 +422,9 @@ void ImGui_ImplWGPU_RenderDrawData(ImDrawData* draw_data, WGPURenderPassEncoder
         {
             nullptr,
             "Dear ImGui Index buffer",
+#ifdef IMGUI_IMPL_WEBGPU_BACKEND_DAWN
+            WGPU_STRLEN,
+#endif
             WGPUBufferUsage_CopyDst | WGPUBufferUsage_Index,
             MEMALIGN(fr->IndexBufferSize * sizeof(ImDrawIdx), 4),
             false
@@ -406,11 +441,11 @@ void ImGui_ImplWGPU_RenderDrawData(ImDrawData* draw_data, WGPURenderPassEncoder
     ImDrawIdx* idx_dst = (ImDrawIdx*)fr->IndexBufferHost;
     for (int n = 0; n < draw_data->CmdListsCount; n++)
     {
-        const ImDrawList* cmd_list = draw_data->CmdLists[n];
-        memcpy(vtx_dst, cmd_list->VtxBuffer.Data, cmd_list->VtxBuffer.Size * sizeof(ImDrawVert));
-        memcpy(idx_dst, cmd_list->IdxBuffer.Data, cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx));
-        vtx_dst += cmd_list->VtxBuffer.Size;
-        idx_dst += cmd_list->IdxBuffer.Size;
+        const ImDrawList* draw_list = draw_data->CmdLists[n];
+        memcpy(vtx_dst, draw_list->VtxBuffer.Data, draw_list->VtxBuffer.Size * sizeof(ImDrawVert));
+        memcpy(idx_dst, draw_list->IdxBuffer.Data, draw_list->IdxBuffer.Size * sizeof(ImDrawIdx));
+        vtx_dst += draw_list->VtxBuffer.Size;
+        idx_dst += draw_list->IdxBuffer.Size;
     }
     int64_t vb_write_size = MEMALIGN((char*)vtx_dst - (char*)fr->VertexBufferHost, 4);
     int64_t ib_write_size = MEMALIGN((char*)idx_dst - (char*)fr->IndexBufferHost, 4);
@@ -420,6 +455,13 @@ void ImGui_ImplWGPU_RenderDrawData(ImDrawData* draw_data, WGPURenderPassEncoder
     // Setup desired render state
     ImGui_ImplWGPU_SetupRenderState(draw_data, pass_encoder, fr);
 
+    // Setup render state structure (for callbacks and custom texture bindings)
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    ImGui_ImplWGPU_RenderState render_state;
+    render_state.Device = bd->wgpuDevice;
+    render_state.RenderPassEncoder = pass_encoder;
+    platform_io.Renderer_RenderState = &render_state;
+
     // Render command lists
     // (Because we merged all buffers into a single one, we maintain our own offset into them)
     int global_vtx_offset = 0;
@@ -428,10 +470,10 @@ void ImGui_ImplWGPU_RenderDrawData(ImDrawData* draw_data, WGPURenderPassEncoder
     ImVec2 clip_off = draw_data->DisplayPos;
     for (int n = 0; n < draw_data->CmdListsCount; n++)
     {
-        const ImDrawList* cmd_list = draw_data->CmdLists[n];
-        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        const ImDrawList* draw_list = draw_data->CmdLists[n];
+        for (int cmd_i = 0; cmd_i < draw_list->CmdBuffer.Size; cmd_i++)
         {
-            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            const ImDrawCmd* pcmd = &draw_list->CmdBuffer[cmd_i];
             if (pcmd->UserCallback != nullptr)
             {
                 // User callback, registered via ImDrawList::AddCallback()
@@ -439,7 +481,7 @@ void ImGui_ImplWGPU_RenderDrawData(ImDrawData* draw_data, WGPURenderPassEncoder
                 if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
                     ImGui_ImplWGPU_SetupRenderState(draw_data, pass_encoder, fr);
                 else
-                    pcmd->UserCallback(cmd_list, pcmd);
+                    pcmd->UserCallback(draw_list, pcmd);
             }
             else
             {
@@ -475,9 +517,10 @@ void ImGui_ImplWGPU_RenderDrawData(ImDrawData* draw_data, WGPURenderPassEncoder
                 wgpuRenderPassEncoderDrawIndexed(pass_encoder, pcmd->ElemCount, 1, pcmd->IdxOffset + global_idx_offset, pcmd->VtxOffset + global_vtx_offset, 0);
             }
         }
-        global_idx_offset += cmd_list->IdxBuffer.Size;
-        global_vtx_offset += cmd_list->VtxBuffer.Size;
+        global_idx_offset += draw_list->IdxBuffer.Size;
+        global_vtx_offset += draw_list->VtxBuffer.Size;
     }
+    platform_io.Renderer_RenderState = nullptr;
 }
 
 static void ImGui_ImplWGPU_CreateFontsTexture()
@@ -492,7 +535,11 @@ static void ImGui_ImplWGPU_CreateFontsTexture()
     // Upload texture to graphics system
     {
         WGPUTextureDescriptor tex_desc = {};
+#ifdef IMGUI_IMPL_WEBGPU_BACKEND_DAWN
+        tex_desc.label = { "Dear ImGui Font Texture", WGPU_STRLEN };
+#else
         tex_desc.label = "Dear ImGui Font Texture";
+#endif
         tex_desc.dimension = WGPUTextureDimension_2D;
         tex_desc.size.width = width;
         tex_desc.size.height = height;
@@ -536,9 +583,9 @@ static void ImGui_ImplWGPU_CreateFontsTexture()
         sampler_desc.minFilter = WGPUFilterMode_Linear;
         sampler_desc.magFilter = WGPUFilterMode_Linear;
         sampler_desc.mipmapFilter = WGPUMipmapFilterMode_Linear;
-        sampler_desc.addressModeU = WGPUAddressMode_Repeat;
-        sampler_desc.addressModeV = WGPUAddressMode_Repeat;
-        sampler_desc.addressModeW = WGPUAddressMode_Repeat;
+        sampler_desc.addressModeU = WGPUAddressMode_ClampToEdge;
+        sampler_desc.addressModeV = WGPUAddressMode_ClampToEdge;
+        sampler_desc.addressModeW = WGPUAddressMode_ClampToEdge;
         sampler_desc.maxAnisotropy = 1;
         bd->renderResources.Sampler = wgpuDeviceCreateSampler(bd->wgpuDevice, &sampler_desc);
     }
@@ -555,6 +602,9 @@ static void ImGui_ImplWGPU_CreateUniformBuffer()
     {
         nullptr,
         "Dear ImGui Uniform buffer",
+#ifdef IMGUI_IMPL_WEBGPU_BACKEND_DAWN
+        WGPU_STRLEN,
+#endif
         WGPUBufferUsage_CopyDst | WGPUBufferUsage_Uniform,
         MEMALIGN(sizeof(Uniforms), 16),
         false
@@ -660,7 +710,11 @@ bool ImGui_ImplWGPU_CreateDeviceObjects()
     // Create depth-stencil State
     WGPUDepthStencilState depth_stencil_state = {};
     depth_stencil_state.format = bd->depthStencilFormat;
+#ifdef IMGUI_IMPL_WEBGPU_BACKEND_DAWN
+    depth_stencil_state.depthWriteEnabled = WGPUOptionalBool_False;
+#else
     depth_stencil_state.depthWriteEnabled = false;
+#endif
     depth_stencil_state.depthCompare = WGPUCompareFunction_Always;
     depth_stencil_state.stencilFront.compare = WGPUCompareFunction_Always;
     depth_stencil_state.stencilFront.failOp = WGPUStencilOperation_Keep;
@@ -730,7 +784,15 @@ bool ImGui_ImplWGPU_Init(ImGui_ImplWGPU_InitInfo* init_info)
     // Setup backend capabilities flags
     ImGui_ImplWGPU_Data* bd = IM_NEW(ImGui_ImplWGPU_Data)();
     io.BackendRendererUserData = (void*)bd;
+#if defined(__EMSCRIPTEN__)
+    io.BackendRendererName = "imgui_impl_webgpu_emscripten";
+#elif defined(IMGUI_IMPL_WEBGPU_BACKEND_DAWN)
+    io.BackendRendererName = "imgui_impl_webgpu_dawn";
+#elif defined(IMGUI_IMPL_WEBGPU_BACKEND_WGPU)
+    io.BackendRendererName = "imgui_impl_webgpu_wgpu";
+#else
     io.BackendRendererName = "imgui_impl_webgpu";
+#endif
     io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset;  // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
 
     bd->initInfo = *init_info;

backends/imgui_impl_wgpu.h

@@ -2,9 +2,19 @@
 // This needs to be used along with a Platform Binding (e.g. GLFW)
 // (Please note that WebGPU is currently experimental, will not run on non-beta browsers, and may break.)
 
+// Important note to dawn and/or wgpu users: when targeting native platforms (i.e. NOT emscripten),
+// one of IMGUI_IMPL_WEBGPU_BACKEND_DAWN or IMGUI_IMPL_WEBGPU_BACKEND_WGPU must be provided.
+// Add #define to your imconfig.h file, or as a compilation flag in your build system.
+// This requirement will be removed once WebGPU stabilizes and backends converge on a unified interface.
+//#define IMGUI_IMPL_WEBGPU_BACKEND_DAWN
+//#define IMGUI_IMPL_WEBGPU_BACKEND_WGPU
+
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'WGPUTextureView' as ImTextureID. Read the FAQ about ImTextureID!
-//  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
+//  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
+//  [X] Renderer: Expose selected render state for draw callbacks to use. Access in '(ImGui_ImplXXXX_RenderState*)GetPlatformIO().Renderer_RenderState'.
+// Missing features:
+//  [ ] Renderer: Multi-viewport support (multiple windows). Not meaningful on the web.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -37,13 +47,23 @@ struct ImGui_ImplWGPU_InitInfo
     }
 };
 
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
 IMGUI_IMPL_API bool ImGui_ImplWGPU_Init(ImGui_ImplWGPU_InitInfo* init_info);
 IMGUI_IMPL_API void ImGui_ImplWGPU_Shutdown();
 IMGUI_IMPL_API void ImGui_ImplWGPU_NewFrame();
 IMGUI_IMPL_API void ImGui_ImplWGPU_RenderDrawData(ImDrawData* draw_data, WGPURenderPassEncoder pass_encoder);
 
 // Use if you want to reset your rendering device without losing Dear ImGui state.
-IMGUI_IMPL_API void ImGui_ImplWGPU_InvalidateDeviceObjects();
 IMGUI_IMPL_API bool ImGui_ImplWGPU_CreateDeviceObjects();
+IMGUI_IMPL_API void ImGui_ImplWGPU_InvalidateDeviceObjects();
+
+// [BETA] Selected render state data shared with callbacks.
+// This is temporarily stored in GetPlatformIO().Renderer_RenderState during the ImGui_ImplWGPU_RenderDrawData() call.
+// (Please open an issue if you feel you need access to more data)
+struct ImGui_ImplWGPU_RenderState
+{
+    WGPUDevice                  Device;
+    WGPURenderPassEncoder       RenderPassEncoder;
+};
 
 #endif // #ifndef IMGUI_DISABLE

backends/imgui_impl_win32.cpp

@@ -4,9 +4,10 @@
 // Implemented features:
 //  [X] Platform: Clipboard support (for Win32 this is actually part of core dear imgui)
 //  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen/Pen.
-//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy VK_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy VK_* values are obsolete since 1.87 and not supported since 1.91.5]
 //  [X] Platform: Gamepad support. Enabled with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
-//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+//  [X] Platform: Mouse cursor shape and visibility (ImGuiBackendFlags_HasMouseCursors). Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+//  [X] Platform: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -21,6 +22,11 @@
 
 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
+//  2024-XX-XX: Platform: Added support for multiple windows via the ImGuiPlatformIO interface.
+//  2024-11-21: [Docking] Fixed a crash when multiple processes are running with multi-viewports, caused by misusage of GetProp(). (#8162, #8069)
+//  2024-10-28: [Docking] Rely on property stored inside HWND to retrieve context/viewport, should facilitate attempt to use this for parallel contexts. (#8069)
+//  2024-09-16: [Docking] Inputs: fixed an issue where a viewport destroyed while clicking would hog mouse tracking and temporary lead to incorrect update of HoveredWindow. (#7971)
+//  2024-07-08: Inputs: Fixed ImGuiMod_Super being mapped to VK_APPS instead of VK_LWIN||VK_RWIN. (#7768)
 //  2023-10-05: Inputs: Added support for extra ImGuiKey values: F13 to F24 function keys, app back/forward keys.
 //  2023-09-25: Inputs: Synthesize key-down event on key-up for VK_SNAPSHOT / ImGuiKey_PrintScreen as Windows doesn't emit it (same behavior as GLFW/SDL).
 //  2023-09-07: Inputs: Added support for keyboard codepage conversion for when application is compiled in MBCS mode and using a non-Unicode window.
@@ -98,19 +104,26 @@ typedef DWORD(WINAPI* PFN_XInputGetState)(DWORD, XINPUT_STATE*);
 #endif
 #if defined(__GNUC__)
 #pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wpragmas"                  // warning: unknown option after '#pragma GCC diagnostic' kind
 #pragma GCC diagnostic ignored "-Wcast-function-type"       // warning: cast between incompatible function types (for loader)
 #endif
 
+// Forward Declarations
+static void ImGui_ImplWin32_InitMultiViewportSupport(bool platform_has_own_dc);
+static void ImGui_ImplWin32_ShutdownMultiViewportSupport();
+static void ImGui_ImplWin32_UpdateMonitors();
+
 struct ImGui_ImplWin32_Data
 {
     HWND                        hWnd;
     HWND                        MouseHwnd;
-    int                         MouseTrackedArea;   // 0: not tracked, 1: client are, 2: non-client area
+    int                         MouseTrackedArea;   // 0: not tracked, 1: client area, 2: non-client area
     int                         MouseButtonsDown;
     INT64                       Time;
     INT64                       TicksPerSecond;
     ImGuiMouseCursor            LastMouseCursor;
     UINT32                      KeyboardCodePage;
+    bool                        WantUpdateMonitors;
 
 #ifndef IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
     bool                        HasGamepad;
@@ -131,12 +144,16 @@ static ImGui_ImplWin32_Data* ImGui_ImplWin32_GetBackendData()
 {
     return ImGui::GetCurrentContext() ? (ImGui_ImplWin32_Data*)ImGui::GetIO().BackendPlatformUserData : nullptr;
 }
+static ImGui_ImplWin32_Data* ImGui_ImplWin32_GetBackendData(ImGuiIO& io)
+{
+    return (ImGui_ImplWin32_Data*)io.BackendPlatformUserData;
+}
 
 // Functions
-static void ImGui_ImplWin32_UpdateKeyboardCodePage()
+static void ImGui_ImplWin32_UpdateKeyboardCodePage(ImGuiIO& io)
 {
     // Retrieve keyboard code page, required for handling of non-Unicode Windows.
-    ImGui_ImplWin32_Data* bd = ImGui_ImplWin32_GetBackendData();
+    ImGui_ImplWin32_Data* bd = ImGui_ImplWin32_GetBackendData(io);
     HKL keyboard_layout = ::GetKeyboardLayout(0);
     LCID keyboard_lcid = MAKELCID(HIWORD(keyboard_layout), SORT_DEFAULT);
     if (::GetLocaleInfoA(keyboard_lcid, (LOCALE_RETURN_NUMBER | LOCALE_IDEFAULTANSICODEPAGE), (LPSTR)&bd->KeyboardCodePage, sizeof(bd->KeyboardCodePage)) == 0)
@@ -161,16 +178,26 @@ static bool ImGui_ImplWin32_InitEx(void* hwnd, bool platform_has_own_dc)
     io.BackendPlatformName = "imgui_impl_win32";
     io.BackendFlags |= ImGuiBackendFlags_HasMouseCursors;         // We can honor GetMouseCursor() values (optional)
     io.BackendFlags |= ImGuiBackendFlags_HasSetMousePos;          // We can honor io.WantSetMousePos requests (optional, rarely used)
+    io.BackendFlags |= ImGuiBackendFlags_PlatformHasViewports;    // We can create multi-viewports on the Platform side (optional)
+    io.BackendFlags |= ImGuiBackendFlags_HasMouseHoveredViewport; // We can call io.AddMouseViewportEvent() with correct data (optional)
 
     bd->hWnd = (HWND)hwnd;
     bd->TicksPerSecond = perf_frequency;
     bd->Time = perf_counter;
     bd->LastMouseCursor = ImGuiMouseCursor_COUNT;
-    ImGui_ImplWin32_UpdateKeyboardCodePage();
+    ImGui_ImplWin32_UpdateKeyboardCodePage(io);
 
-    // Set platform dependent data in viewport
-    ImGui::GetMainViewport()->PlatformHandleRaw = (void*)hwnd;
-    IM_UNUSED(platform_has_own_dc); // Used in 'docking' branch
+    // Update monitor a first time during init
+    ImGui_ImplWin32_UpdateMonitors();
+
+    // Our mouse update function expect PlatformHandle to be filled for the main viewport
+    ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+    main_viewport->PlatformHandle = main_viewport->PlatformHandleRaw = (void*)bd->hWnd;
+
+    // Be aware that GetPropA()/SetPropA() may be accessed from other processes.
+    // So as we store a pointer in IMGUI_CONTEXT we need to make sure we only call GetPropA() on windows owned by our process.
+    ::SetPropA(bd->hWnd, "IMGUI_CONTEXT", ImGui::GetCurrentContext());
+    ImGui_ImplWin32_InitMultiViewportSupport(platform_has_own_dc);
 
     // Dynamically load XInput library
 #ifndef IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
@@ -213,6 +240,9 @@ void    ImGui_ImplWin32_Shutdown()
     IM_ASSERT(bd != nullptr && "No platform backend to shutdown, or already shutdown?");
     ImGuiIO& io = ImGui::GetIO();
 
+    ::SetPropA(bd->hWnd, "IMGUI_CONTEXT", nullptr);
+    ImGui_ImplWin32_ShutdownMultiViewportSupport();
+
     // Unload XInput library
 #ifndef IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
     if (bd->XInputDLL)
@@ -221,17 +251,15 @@ void    ImGui_ImplWin32_Shutdown()
 
     io.BackendPlatformName = nullptr;
     io.BackendPlatformUserData = nullptr;
-    io.BackendFlags &= ~(ImGuiBackendFlags_HasMouseCursors | ImGuiBackendFlags_HasSetMousePos | ImGuiBackendFlags_HasGamepad);
+    io.BackendFlags &= ~(ImGuiBackendFlags_HasMouseCursors | ImGuiBackendFlags_HasSetMousePos | ImGuiBackendFlags_HasGamepad | ImGuiBackendFlags_PlatformHasViewports | ImGuiBackendFlags_HasMouseHoveredViewport);
     IM_DELETE(bd);
 }
 
-static bool ImGui_ImplWin32_UpdateMouseCursor()
+static bool ImGui_ImplWin32_UpdateMouseCursor(ImGuiIO& io, ImGuiMouseCursor imgui_cursor)
 {
-    ImGuiIO& io = ImGui::GetIO();
     if (io.ConfigFlags & ImGuiConfigFlags_NoMouseCursorChange)
         return false;
 
-    ImGuiMouseCursor imgui_cursor = ImGui::GetMouseCursor();
     if (imgui_cursor == ImGuiMouseCursor_None || io.MouseDrawCursor)
     {
         // Hide OS mouse cursor if imgui is drawing it or if it wants no cursor
@@ -263,73 +291,106 @@ static bool IsVkDown(int vk)
     return (::GetKeyState(vk) & 0x8000) != 0;
 }
 
-static void ImGui_ImplWin32_AddKeyEvent(ImGuiKey key, bool down, int native_keycode, int native_scancode = -1)
+static void ImGui_ImplWin32_AddKeyEvent(ImGuiIO& io, ImGuiKey key, bool down, int native_keycode, int native_scancode = -1)
 {
-    ImGuiIO& io = ImGui::GetIO();
     io.AddKeyEvent(key, down);
     io.SetKeyEventNativeData(key, native_keycode, native_scancode); // To support legacy indexing (<1.87 user code)
     IM_UNUSED(native_scancode);
 }
 
-static void ImGui_ImplWin32_ProcessKeyEventsWorkarounds()
+static void ImGui_ImplWin32_ProcessKeyEventsWorkarounds(ImGuiIO& io)
 {
     // Left & right Shift keys: when both are pressed together, Windows tend to not generate the WM_KEYUP event for the first released one.
     if (ImGui::IsKeyDown(ImGuiKey_LeftShift) && !IsVkDown(VK_LSHIFT))
-        ImGui_ImplWin32_AddKeyEvent(ImGuiKey_LeftShift, false, VK_LSHIFT);
+        ImGui_ImplWin32_AddKeyEvent(io, ImGuiKey_LeftShift, false, VK_LSHIFT);
     if (ImGui::IsKeyDown(ImGuiKey_RightShift) && !IsVkDown(VK_RSHIFT))
-        ImGui_ImplWin32_AddKeyEvent(ImGuiKey_RightShift, false, VK_RSHIFT);
+        ImGui_ImplWin32_AddKeyEvent(io, ImGuiKey_RightShift, false, VK_RSHIFT);
 
     // Sometimes WM_KEYUP for Win key is not passed down to the app (e.g. for Win+V on some setups, according to GLFW).
     if (ImGui::IsKeyDown(ImGuiKey_LeftSuper) && !IsVkDown(VK_LWIN))
-        ImGui_ImplWin32_AddKeyEvent(ImGuiKey_LeftSuper, false, VK_LWIN);
+        ImGui_ImplWin32_AddKeyEvent(io, ImGuiKey_LeftSuper, false, VK_LWIN);
     if (ImGui::IsKeyDown(ImGuiKey_RightSuper) && !IsVkDown(VK_RWIN))
-        ImGui_ImplWin32_AddKeyEvent(ImGuiKey_RightSuper, false, VK_RWIN);
+        ImGui_ImplWin32_AddKeyEvent(io, ImGuiKey_RightSuper, false, VK_RWIN);
 }
 
-static void ImGui_ImplWin32_UpdateKeyModifiers()
+static void ImGui_ImplWin32_UpdateKeyModifiers(ImGuiIO& io)
 {
-    ImGuiIO& io = ImGui::GetIO();
     io.AddKeyEvent(ImGuiMod_Ctrl, IsVkDown(VK_CONTROL));
     io.AddKeyEvent(ImGuiMod_Shift, IsVkDown(VK_SHIFT));
     io.AddKeyEvent(ImGuiMod_Alt, IsVkDown(VK_MENU));
-    io.AddKeyEvent(ImGuiMod_Super, IsVkDown(VK_APPS));
+    io.AddKeyEvent(ImGuiMod_Super, IsVkDown(VK_LWIN) || IsVkDown(VK_RWIN));
 }
 
-static void ImGui_ImplWin32_UpdateMouseData()
+static ImGuiViewport* ImGui_ImplWin32_FindViewportByPlatformHandle(ImGuiPlatformIO& platform_io, HWND hwnd)
 {
-    ImGui_ImplWin32_Data* bd = ImGui_ImplWin32_GetBackendData();
-    ImGuiIO& io = ImGui::GetIO();
+    // We cannot use ImGui::FindViewportByPlatformHandle() because it doesn't take a context.
+    // When called from ImGui_ImplWin32_WndProcHandler_PlatformWindow() we don't assume that context is bound.
+    //return ImGui::FindViewportByPlatformHandle((void*)hwnd);
+    for (ImGuiViewport* viewport : platform_io.Viewports)
+        if (viewport->PlatformHandle == hwnd)
+            return viewport;
+    return nullptr;
+}
+
+// This code supports multi-viewports (multiple OS Windows mapped into different Dear ImGui viewports)
+// Because of that, it is a little more complicated than your typical single-viewport binding code!
+static void ImGui_ImplWin32_UpdateMouseData(ImGuiIO& io, ImGuiPlatformIO& platform_io)
+{
+    ImGui_ImplWin32_Data* bd = ImGui_ImplWin32_GetBackendData(io);
     IM_ASSERT(bd->hWnd != 0);
 
+    POINT mouse_screen_pos;
+    bool has_mouse_screen_pos = ::GetCursorPos(&mouse_screen_pos) != 0;
+
     HWND focused_window = ::GetForegroundWindow();
-    const bool is_app_focused = (focused_window == bd->hWnd);
+    const bool is_app_focused = (focused_window && (focused_window == bd->hWnd || ::IsChild(focused_window, bd->hWnd) || ImGui_ImplWin32_FindViewportByPlatformHandle(platform_io, focused_window)));
     if (is_app_focused)
     {
-        // (Optional) Set OS mouse position from Dear ImGui if requested (rarely used, only when ImGuiConfigFlags_NavEnableSetMousePos is enabled by user)
+        // (Optional) Set OS mouse position from Dear ImGui if requested (rarely used, only when io.ConfigNavMoveSetMousePos is enabled by user)
+        // When multi-viewports are enabled, all Dear ImGui positions are same as OS positions.
         if (io.WantSetMousePos)
         {
             POINT pos = { (int)io.MousePos.x, (int)io.MousePos.y };
-            if (::ClientToScreen(bd->hWnd, &pos))
-                ::SetCursorPos(pos.x, pos.y);
+            if ((io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable) == 0)
+                ::ClientToScreen(focused_window, &pos);
+            ::SetCursorPos(pos.x, pos.y);
         }
 
         // (Optional) Fallback to provide mouse position when focused (WM_MOUSEMOVE already provides this when hovered or captured)
         // This also fills a short gap when clicking non-client area: WM_NCMOUSELEAVE -> modal OS move -> gap -> WM_NCMOUSEMOVE
-        if (!io.WantSetMousePos && bd->MouseTrackedArea == 0)
+        if (!io.WantSetMousePos && bd->MouseTrackedArea == 0 && has_mouse_screen_pos)
         {
-            POINT pos;
-            if (::GetCursorPos(&pos) && ::ScreenToClient(bd->hWnd, &pos))
-                io.AddMousePosEvent((float)pos.x, (float)pos.y);
+            // Single viewport mode: mouse position in client window coordinates (io.MousePos is (0,0) when the mouse is on the upper-left corner of the app window)
+            // (This is the position you can get with ::GetCursorPos() + ::ScreenToClient() or WM_MOUSEMOVE.)
+            // Multi-viewport mode: mouse position in OS absolute coordinates (io.MousePos is (0,0) when the mouse is on the upper-left of the primary monitor)
+            // (This is the position you can get with ::GetCursorPos() or WM_MOUSEMOVE + ::ClientToScreen(). In theory adding viewport->Pos to a client position would also be the same.)
+            POINT mouse_pos = mouse_screen_pos;
+            if (!(io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable))
+                ::ScreenToClient(bd->hWnd, &mouse_pos);
+            io.AddMousePosEvent((float)mouse_pos.x, (float)mouse_pos.y);
         }
     }
+
+    // (Optional) When using multiple viewports: call io.AddMouseViewportEvent() with the viewport the OS mouse cursor is hovering.
+    // If ImGuiBackendFlags_HasMouseHoveredViewport is not set by the backend, Dear imGui will ignore this field and infer the information using its flawed heuristic.
+    // - [X] Win32 backend correctly ignore viewports with the _NoInputs flag (here using ::WindowFromPoint with WM_NCHITTEST + HTTRANSPARENT in WndProc does that)
+    //       Some backend are not able to handle that correctly. If a backend report an hovered viewport that has the _NoInputs flag (e.g. when dragging a window
+    //       for docking, the viewport has the _NoInputs flag in order to allow us to find the viewport under), then Dear ImGui is forced to ignore the value reported
+    //       by the backend, and use its flawed heuristic to guess the viewport behind.
+    // - [X] Win32 backend correctly reports this regardless of another viewport behind focused and dragged from (we need this to find a useful drag and drop target).
+    ImGuiID mouse_viewport_id = 0;
+    if (has_mouse_screen_pos)
+        if (HWND hovered_hwnd = ::WindowFromPoint(mouse_screen_pos))
+            if (ImGuiViewport* viewport = ImGui_ImplWin32_FindViewportByPlatformHandle(platform_io, hovered_hwnd))
+                mouse_viewport_id = viewport->ID;
+    io.AddMouseViewportEvent(mouse_viewport_id);
 }
 
 // Gamepad navigation mapping
-static void ImGui_ImplWin32_UpdateGamepads()
+static void ImGui_ImplWin32_UpdateGamepads(ImGuiIO& io)
 {
 #ifndef IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
-    ImGuiIO& io = ImGui::GetIO();
-    ImGui_ImplWin32_Data* bd = ImGui_ImplWin32_GetBackendData();
+    ImGui_ImplWin32_Data* bd = ImGui_ImplWin32_GetBackendData(io);
     //if ((io.ConfigFlags & ImGuiConfigFlags_NavEnableGamepad) == 0) // FIXME: Technically feeding gamepad shouldn't depend on this now that they are regular inputs.
     //    return;
 
@@ -378,7 +439,40 @@ static void ImGui_ImplWin32_UpdateGamepads()
     MAP_ANALOG(ImGuiKey_GamepadRStickDown,      gamepad.sThumbRY, -XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE, -32768);
     #undef MAP_BUTTON
     #undef MAP_ANALOG
-#endif // #ifndef IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
+#else // #ifndef IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
+    IM_UNUSED(io);
+#endif
+}
+
+static BOOL CALLBACK ImGui_ImplWin32_UpdateMonitors_EnumFunc(HMONITOR monitor, HDC, LPRECT, LPARAM)
+{
+    MONITORINFO info = {};
+    info.cbSize = sizeof(MONITORINFO);
+    if (!::GetMonitorInfo(monitor, &info))
+        return TRUE;
+    ImGuiPlatformMonitor imgui_monitor;
+    imgui_monitor.MainPos = ImVec2((float)info.rcMonitor.left, (float)info.rcMonitor.top);
+    imgui_monitor.MainSize = ImVec2((float)(info.rcMonitor.right - info.rcMonitor.left), (float)(info.rcMonitor.bottom - info.rcMonitor.top));
+    imgui_monitor.WorkPos = ImVec2((float)info.rcWork.left, (float)info.rcWork.top);
+    imgui_monitor.WorkSize = ImVec2((float)(info.rcWork.right - info.rcWork.left), (float)(info.rcWork.bottom - info.rcWork.top));
+    imgui_monitor.DpiScale = ImGui_ImplWin32_GetDpiScaleForMonitor(monitor);
+    imgui_monitor.PlatformHandle = (void*)monitor;
+    if (imgui_monitor.DpiScale <= 0.0f)
+        return TRUE; // Some accessibility applications are declaring virtual monitors with a DPI of 0, see #7902.
+    ImGuiPlatformIO& io = ImGui::GetPlatformIO();
+    if (info.dwFlags & MONITORINFOF_PRIMARY)
+        io.Monitors.push_front(imgui_monitor);
+    else
+        io.Monitors.push_back(imgui_monitor);
+    return TRUE;
+}
+
+static void ImGui_ImplWin32_UpdateMonitors()
+{
+    ImGui_ImplWin32_Data* bd = ImGui_ImplWin32_GetBackendData();
+    ImGui::GetPlatformIO().Monitors.resize(0);
+    ::EnumDisplayMonitors(nullptr, nullptr, ImGui_ImplWin32_UpdateMonitors_EnumFunc, 0);
+    bd->WantUpdateMonitors = false;
 }
 
 void    ImGui_ImplWin32_NewFrame()
@@ -386,11 +480,14 @@ void    ImGui_ImplWin32_NewFrame()
     ImGui_ImplWin32_Data* bd = ImGui_ImplWin32_GetBackendData();
     IM_ASSERT(bd != nullptr && "Context or backend not initialized? Did you call ImGui_ImplWin32_Init()?");
     ImGuiIO& io = ImGui::GetIO();
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
 
     // Setup display size (every frame to accommodate for window resizing)
     RECT rect = { 0, 0, 0, 0 };
     ::GetClientRect(bd->hWnd, &rect);
     io.DisplaySize = ImVec2((float)(rect.right - rect.left), (float)(rect.bottom - rect.top));
+    if (bd->WantUpdateMonitors)
+        ImGui_ImplWin32_UpdateMonitors();
 
     // Setup time step
     INT64 current_time = 0;
@@ -399,29 +496,32 @@ void    ImGui_ImplWin32_NewFrame()
     bd->Time = current_time;
 
     // Update OS mouse position
-    ImGui_ImplWin32_UpdateMouseData();
+    ImGui_ImplWin32_UpdateMouseData(io, platform_io);
 
     // Process workarounds for known Windows key handling issues
-    ImGui_ImplWin32_ProcessKeyEventsWorkarounds();
+    ImGui_ImplWin32_ProcessKeyEventsWorkarounds(io);
 
     // Update OS mouse cursor with the cursor requested by imgui
     ImGuiMouseCursor mouse_cursor = io.MouseDrawCursor ? ImGuiMouseCursor_None : ImGui::GetMouseCursor();
     if (bd->LastMouseCursor != mouse_cursor)
     {
         bd->LastMouseCursor = mouse_cursor;
-        ImGui_ImplWin32_UpdateMouseCursor();
+        ImGui_ImplWin32_UpdateMouseCursor(io, mouse_cursor);
     }
 
     // Update game controllers (if enabled and available)
-    ImGui_ImplWin32_UpdateGamepads();
+    ImGui_ImplWin32_UpdateGamepads(io);
 }
 
-// There is no distinct VK_xxx for keypad enter, instead it is VK_RETURN + KF_EXTENDED, we assign it an arbitrary value to make code more readable (VK_ codes go up to 255)
-#define IM_VK_KEYPAD_ENTER      (VK_RETURN + 256)
-
 // Map VK_xxx to ImGuiKey_xxx.
-static ImGuiKey ImGui_ImplWin32_VirtualKeyToImGuiKey(WPARAM wParam)
+// Not static to allow third-party code to use that if they want to (but undocumented)
+ImGuiKey ImGui_ImplWin32_KeyEventToImGuiKey(WPARAM wParam, LPARAM lParam);
+ImGuiKey ImGui_ImplWin32_KeyEventToImGuiKey(WPARAM wParam, LPARAM lParam)
 {
+    // There is no distinct VK_xxx for keypad enter, instead it is VK_RETURN + KF_EXTENDED.
+    if ((wParam == VK_RETURN) && (HIWORD(lParam) & KF_EXTENDED))
+        return ImGuiKey_KeypadEnter;
+
     switch (wParam)
     {
         case VK_TAB: return ImGuiKey_Tab;
@@ -470,7 +570,6 @@ static ImGuiKey ImGui_ImplWin32_VirtualKeyToImGuiKey(WPARAM wParam)
         case VK_MULTIPLY: return ImGuiKey_KeypadMultiply;
         case VK_SUBTRACT: return ImGuiKey_KeypadSubtract;
         case VK_ADD: return ImGuiKey_KeypadAdd;
-        case IM_VK_KEYPAD_ENTER: return ImGuiKey_KeypadEnter;
         case VK_LSHIFT: return ImGuiKey_LeftShift;
         case VK_LCONTROL: return ImGuiKey_LeftCtrl;
         case VK_LMENU: return ImGuiKey_LeftAlt;
@@ -554,22 +653,10 @@ static ImGuiKey ImGui_ImplWin32_VirtualKeyToImGuiKey(WPARAM wParam)
 #define DBT_DEVNODES_CHANGED 0x0007
 #endif
 
-// Win32 message handler (process Win32 mouse/keyboard inputs, etc.)
-// Call from your application's message handler. Keep calling your message handler unless this function returns TRUE.
-// When implementing your own backend, you can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if Dear ImGui wants to use your inputs.
-// - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application, or clear/overwrite your copy of the mouse data.
-// - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application, or clear/overwrite your copy of the keyboard data.
-// Generally you may always pass all inputs to Dear ImGui, and hide them from your application based on those two flags.
-// PS: In this Win32 handler, we use the capture API (GetCapture/SetCapture/ReleaseCapture) to be able to read mouse coordinates when dragging mouse outside of our window bounds.
-// PS: We treat DBLCLK messages as regular mouse down messages, so this code will work on windows classes that have the CS_DBLCLKS flag set. Our own example app code doesn't set this flag.
-#if 0
-// Copy this line into your .cpp file to forward declare the function.
-extern IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam);
-#endif
-
+// Helper to obtain the source of mouse messages.
 // See https://learn.microsoft.com/en-us/windows/win32/tablet/system-events-and-mouse-messages
 // Prefer to call this at the top of the message handler to avoid the possibility of other Win32 calls interfering with this.
-static ImGuiMouseSource GetMouseSourceFromMessageExtraInfo()
+static ImGuiMouseSource ImGui_ImplWin32_GetMouseSourceFromMessageExtraInfo()
 {
     LPARAM extra_info = ::GetMessageExtraInfo();
     if ((extra_info & 0xFFFFFF80) == 0xFF515700)
@@ -579,22 +666,40 @@ static ImGuiMouseSource GetMouseSourceFromMessageExtraInfo()
     return ImGuiMouseSource_Mouse;
 }
 
+// Win32 message handler (process Win32 mouse/keyboard inputs, etc.)
+// Call from your application's message handler. Keep calling your message handler unless this function returns TRUE.
+// When implementing your own backend, you can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if Dear ImGui wants to use your inputs.
+// - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application, or clear/overwrite your copy of the mouse data.
+// - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application, or clear/overwrite your copy of the keyboard data.
+// Generally you may always pass all inputs to Dear ImGui, and hide them from your application based on those two flags.
+// PS: We treat DBLCLK messages as regular mouse down messages, so this code will work on windows classes that have the CS_DBLCLKS flag set. Our own example app code doesn't set this flag.
+
+// Copy either line into your .cpp file to forward declare the function:
+extern IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam);                // Use ImGui::GetCurrentContext()
+extern IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandlerEx(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam, ImGuiIO& io); // Doesn't use ImGui::GetCurrentContext()
+
 IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
 {
     // Most backends don't have silent checks like this one, but we need it because WndProc are called early in CreateWindow().
     // We silently allow both context or just only backend data to be nullptr.
-    ImGui_ImplWin32_Data* bd = ImGui_ImplWin32_GetBackendData();
+    if (ImGui::GetCurrentContext() == nullptr)
+        return 0;
+    return ImGui_ImplWin32_WndProcHandlerEx(hwnd, msg, wParam, lParam, ImGui::GetIO());
+}
+
+// This version is in theory thread-safe in the sense that no path should access ImGui::GetCurrentContext().
+IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandlerEx(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam, ImGuiIO& io)
+{
+    ImGui_ImplWin32_Data* bd = ImGui_ImplWin32_GetBackendData(io);
     if (bd == nullptr)
         return 0;
-    ImGuiIO& io = ImGui::GetIO();
-
     switch (msg)
     {
     case WM_MOUSEMOVE:
     case WM_NCMOUSEMOVE:
     {
         // We need to call TrackMouseEvent in order to receive WM_MOUSELEAVE events
-        ImGuiMouseSource mouse_source = GetMouseSourceFromMessageExtraInfo();
+        ImGuiMouseSource mouse_source = ImGui_ImplWin32_GetMouseSourceFromMessageExtraInfo();
         const int area = (msg == WM_MOUSEMOVE) ? 1 : 2;
         bd->MouseHwnd = hwnd;
         if (bd->MouseTrackedArea != area)
@@ -607,8 +712,11 @@ IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hwnd, UINT msg, WPARA
             bd->MouseTrackedArea = area;
         }
         POINT mouse_pos = { (LONG)GET_X_LPARAM(lParam), (LONG)GET_Y_LPARAM(lParam) };
-        if (msg == WM_NCMOUSEMOVE && ::ScreenToClient(hwnd, &mouse_pos) == FALSE) // WM_NCMOUSEMOVE are provided in absolute coordinates.
-            return 0;
+        bool want_absolute_pos = (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable) != 0;
+        if (msg == WM_MOUSEMOVE && want_absolute_pos)    // WM_MOUSEMOVE are client-relative coordinates.
+            ::ClientToScreen(hwnd, &mouse_pos);
+        if (msg == WM_NCMOUSEMOVE && !want_absolute_pos) // WM_NCMOUSEMOVE are absolute coordinates.
+            ::ScreenToClient(hwnd, &mouse_pos);
         io.AddMouseSourceEvent(mouse_source);
         io.AddMousePosEvent((float)mouse_pos.x, (float)mouse_pos.y);
         return 0;
@@ -626,19 +734,29 @@ IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hwnd, UINT msg, WPARA
         }
         return 0;
     }
+    case WM_DESTROY:
+        if (bd->MouseHwnd == hwnd && bd->MouseTrackedArea != 0)
+        {
+            TRACKMOUSEEVENT tme_cancel = { sizeof(tme_cancel), TME_CANCEL, hwnd, 0 };
+            ::TrackMouseEvent(&tme_cancel);
+            bd->MouseHwnd = nullptr;
+            bd->MouseTrackedArea = 0;
+            io.AddMousePosEvent(-FLT_MAX, -FLT_MAX);
+        }
+        return 0;
     case WM_LBUTTONDOWN: case WM_LBUTTONDBLCLK:
     case WM_RBUTTONDOWN: case WM_RBUTTONDBLCLK:
     case WM_MBUTTONDOWN: case WM_MBUTTONDBLCLK:
     case WM_XBUTTONDOWN: case WM_XBUTTONDBLCLK:
     {
-        ImGuiMouseSource mouse_source = GetMouseSourceFromMessageExtraInfo();
+        ImGuiMouseSource mouse_source = ImGui_ImplWin32_GetMouseSourceFromMessageExtraInfo();
         int button = 0;
         if (msg == WM_LBUTTONDOWN || msg == WM_LBUTTONDBLCLK) { button = 0; }
         if (msg == WM_RBUTTONDOWN || msg == WM_RBUTTONDBLCLK) { button = 1; }
         if (msg == WM_MBUTTONDOWN || msg == WM_MBUTTONDBLCLK) { button = 2; }
         if (msg == WM_XBUTTONDOWN || msg == WM_XBUTTONDBLCLK) { button = (GET_XBUTTON_WPARAM(wParam) == XBUTTON1) ? 3 : 4; }
         if (bd->MouseButtonsDown == 0 && ::GetCapture() == nullptr)
-            ::SetCapture(hwnd);
+            ::SetCapture(hwnd); // Allow us to read mouse coordinates when dragging mouse outside of our window bounds.
         bd->MouseButtonsDown |= 1 << button;
         io.AddMouseSourceEvent(mouse_source);
         io.AddMouseButtonEvent(button, true);
@@ -649,7 +767,7 @@ IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hwnd, UINT msg, WPARA
     case WM_MBUTTONUP:
     case WM_XBUTTONUP:
     {
-        ImGuiMouseSource mouse_source = GetMouseSourceFromMessageExtraInfo();
+        ImGuiMouseSource mouse_source = ImGui_ImplWin32_GetMouseSourceFromMessageExtraInfo();
         int button = 0;
         if (msg == WM_LBUTTONUP) { button = 0; }
         if (msg == WM_RBUTTONUP) { button = 1; }
@@ -677,40 +795,37 @@ IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hwnd, UINT msg, WPARA
         if (wParam < 256)
         {
             // Submit modifiers
-            ImGui_ImplWin32_UpdateKeyModifiers();
+            ImGui_ImplWin32_UpdateKeyModifiers(io);
 
-            // Obtain virtual key code
-            // (keypad enter doesn't have its own... VK_RETURN with KF_EXTENDED flag means keypad enter, see IM_VK_KEYPAD_ENTER definition for details, it is mapped to ImGuiKey_KeyPadEnter.)
-            int vk = (int)wParam;
-            if ((wParam == VK_RETURN) && (HIWORD(lParam) & KF_EXTENDED))
-                vk = IM_VK_KEYPAD_ENTER;
-            const ImGuiKey key = ImGui_ImplWin32_VirtualKeyToImGuiKey(vk);
+            // Obtain virtual key code and convert to ImGuiKey
+            const ImGuiKey key = ImGui_ImplWin32_KeyEventToImGuiKey(wParam, lParam);
+            const int vk = (int)wParam;
             const int scancode = (int)LOBYTE(HIWORD(lParam));
 
             // Special behavior for VK_SNAPSHOT / ImGuiKey_PrintScreen as Windows doesn't emit the key down event.
             if (key == ImGuiKey_PrintScreen && !is_key_down)
-                ImGui_ImplWin32_AddKeyEvent(key, true, vk, scancode);
+                ImGui_ImplWin32_AddKeyEvent(io, key, true, vk, scancode);
 
             // Submit key event
             if (key != ImGuiKey_None)
-                ImGui_ImplWin32_AddKeyEvent(key, is_key_down, vk, scancode);
+                ImGui_ImplWin32_AddKeyEvent(io, key, is_key_down, vk, scancode);
 
             // Submit individual left/right modifier events
             if (vk == VK_SHIFT)
             {
                 // Important: Shift keys tend to get stuck when pressed together, missing key-up events are corrected in ImGui_ImplWin32_ProcessKeyEventsWorkarounds()
-                if (IsVkDown(VK_LSHIFT) == is_key_down) { ImGui_ImplWin32_AddKeyEvent(ImGuiKey_LeftShift, is_key_down, VK_LSHIFT, scancode); }
-                if (IsVkDown(VK_RSHIFT) == is_key_down) { ImGui_ImplWin32_AddKeyEvent(ImGuiKey_RightShift, is_key_down, VK_RSHIFT, scancode); }
+                if (IsVkDown(VK_LSHIFT) == is_key_down) { ImGui_ImplWin32_AddKeyEvent(io, ImGuiKey_LeftShift, is_key_down, VK_LSHIFT, scancode); }
+                if (IsVkDown(VK_RSHIFT) == is_key_down) { ImGui_ImplWin32_AddKeyEvent(io, ImGuiKey_RightShift, is_key_down, VK_RSHIFT, scancode); }
             }
             else if (vk == VK_CONTROL)
             {
-                if (IsVkDown(VK_LCONTROL) == is_key_down) { ImGui_ImplWin32_AddKeyEvent(ImGuiKey_LeftCtrl, is_key_down, VK_LCONTROL, scancode); }
-                if (IsVkDown(VK_RCONTROL) == is_key_down) { ImGui_ImplWin32_AddKeyEvent(ImGuiKey_RightCtrl, is_key_down, VK_RCONTROL, scancode); }
+                if (IsVkDown(VK_LCONTROL) == is_key_down) { ImGui_ImplWin32_AddKeyEvent(io, ImGuiKey_LeftCtrl, is_key_down, VK_LCONTROL, scancode); }
+                if (IsVkDown(VK_RCONTROL) == is_key_down) { ImGui_ImplWin32_AddKeyEvent(io, ImGuiKey_RightCtrl, is_key_down, VK_RCONTROL, scancode); }
             }
             else if (vk == VK_MENU)
             {
-                if (IsVkDown(VK_LMENU) == is_key_down) { ImGui_ImplWin32_AddKeyEvent(ImGuiKey_LeftAlt, is_key_down, VK_LMENU, scancode); }
-                if (IsVkDown(VK_RMENU) == is_key_down) { ImGui_ImplWin32_AddKeyEvent(ImGuiKey_RightAlt, is_key_down, VK_RMENU, scancode); }
+                if (IsVkDown(VK_LMENU) == is_key_down) { ImGui_ImplWin32_AddKeyEvent(io, ImGuiKey_LeftAlt, is_key_down, VK_LMENU, scancode); }
+                if (IsVkDown(VK_RMENU) == is_key_down) { ImGui_ImplWin32_AddKeyEvent(io, ImGuiKey_RightAlt, is_key_down, VK_RMENU, scancode); }
             }
         }
         return 0;
@@ -720,7 +835,7 @@ IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hwnd, UINT msg, WPARA
         io.AddFocusEvent(msg == WM_SETFOCUS);
         return 0;
     case WM_INPUTLANGCHANGE:
-        ImGui_ImplWin32_UpdateKeyboardCodePage();
+        ImGui_ImplWin32_UpdateKeyboardCodePage(io);
         return 0;
     case WM_CHAR:
         if (::IsWindowUnicode(hwnd))
@@ -738,7 +853,7 @@ IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hwnd, UINT msg, WPARA
         return 0;
     case WM_SETCURSOR:
         // This is required to restore cursor when transitioning from e.g resize borders to client area.
-        if (LOWORD(lParam) == HTCLIENT && ImGui_ImplWin32_UpdateMouseCursor())
+        if (LOWORD(lParam) == HTCLIENT && ImGui_ImplWin32_UpdateMouseCursor(io, bd->LastMouseCursor))
             return 1;
         return 0;
     case WM_DEVICECHANGE:
@@ -747,6 +862,9 @@ IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hwnd, UINT msg, WPARA
             bd->WantUpdateHasGamepad = true;
 #endif
         return 0;
+    case WM_DISPLAYCHANGE:
+        bd->WantUpdateMonitors = true;
+        return 0;
     }
     return 0;
 }
@@ -811,6 +929,10 @@ typedef DPI_AWARENESS_CONTEXT(WINAPI* PFN_SetThreadDpiAwarenessContext)(DPI_AWAR
 // Helper function to enable DPI awareness without setting up a manifest
 void ImGui_ImplWin32_EnableDpiAwareness()
 {
+    // Make sure monitors will be updated with latest correct scaling
+    if (ImGui_ImplWin32_Data* bd = ImGui_ImplWin32_GetBackendData())
+        bd->WantUpdateMonitors = true;
+
     if (_IsWindows10OrGreater())
     {
         static HINSTANCE user32_dll = ::LoadLibraryA("user32.dll"); // Reference counted per-process
@@ -910,6 +1032,381 @@ void ImGui_ImplWin32_EnableAlphaCompositing(void* hwnd)
     }
 }
 
+//---------------------------------------------------------------------------------------------------------
+// MULTI-VIEWPORT / PLATFORM INTERFACE SUPPORT
+// This is an _advanced_ and _optional_ feature, allowing the backend to create and handle multiple viewports simultaneously.
+// If you are new to dear imgui or creating a new binding for dear imgui, it is recommended that you completely ignore this section first..
+//--------------------------------------------------------------------------------------------------------
+
+// Helper structure we store in the void* RendererUserData field of each ImGuiViewport to easily retrieve our backend data.
+struct ImGui_ImplWin32_ViewportData
+{
+    HWND    Hwnd;
+    HWND    HwndParent;
+    bool    HwndOwned;
+    DWORD   DwStyle;
+    DWORD   DwExStyle;
+
+    ImGui_ImplWin32_ViewportData() { Hwnd = HwndParent = nullptr; HwndOwned = false;  DwStyle = DwExStyle = 0; }
+    ~ImGui_ImplWin32_ViewportData() { IM_ASSERT(Hwnd == nullptr); }
+};
+
+static void ImGui_ImplWin32_GetWin32StyleFromViewportFlags(ImGuiViewportFlags flags, DWORD* out_style, DWORD* out_ex_style)
+{
+    if (flags & ImGuiViewportFlags_NoDecoration)
+        *out_style = WS_POPUP;
+    else
+        *out_style = WS_OVERLAPPEDWINDOW;
+
+    if (flags & ImGuiViewportFlags_NoTaskBarIcon)
+        *out_ex_style = WS_EX_TOOLWINDOW;
+    else
+        *out_ex_style = WS_EX_APPWINDOW;
+
+    if (flags & ImGuiViewportFlags_TopMost)
+        *out_ex_style |= WS_EX_TOPMOST;
+}
+
+static HWND ImGui_ImplWin32_GetHwndFromViewportID(ImGuiID viewport_id)
+{
+    if (viewport_id != 0)
+        if (ImGuiViewport* viewport = ImGui::FindViewportByID(viewport_id))
+            return (HWND)viewport->PlatformHandle;
+    return nullptr;
+}
+
+static void ImGui_ImplWin32_CreateWindow(ImGuiViewport* viewport)
+{
+    ImGui_ImplWin32_ViewportData* vd = IM_NEW(ImGui_ImplWin32_ViewportData)();
+    viewport->PlatformUserData = vd;
+
+    // Select style and parent window
+    ImGui_ImplWin32_GetWin32StyleFromViewportFlags(viewport->Flags, &vd->DwStyle, &vd->DwExStyle);
+    vd->HwndParent = ImGui_ImplWin32_GetHwndFromViewportID(viewport->ParentViewportId);
+
+    // Create window
+    RECT rect = { (LONG)viewport->Pos.x, (LONG)viewport->Pos.y, (LONG)(viewport->Pos.x + viewport->Size.x), (LONG)(viewport->Pos.y + viewport->Size.y) };
+    ::AdjustWindowRectEx(&rect, vd->DwStyle, FALSE, vd->DwExStyle);
+    vd->Hwnd = ::CreateWindowExW(
+        vd->DwExStyle, L"ImGui Platform", L"Untitled", vd->DwStyle,       // Style, class name, window name
+        rect.left, rect.top, rect.right - rect.left, rect.bottom - rect.top,    // Window area
+        vd->HwndParent, nullptr, ::GetModuleHandle(nullptr), nullptr);          // Owner window, Menu, Instance, Param
+    vd->HwndOwned = true;
+    viewport->PlatformRequestResize = false;
+    viewport->PlatformHandle = viewport->PlatformHandleRaw = vd->Hwnd;
+
+    // Secondary viewports store their imgui context
+    ::SetPropA(vd->Hwnd, "IMGUI_CONTEXT", ImGui::GetCurrentContext());
+}
+
+static void ImGui_ImplWin32_DestroyWindow(ImGuiViewport* viewport)
+{
+    ImGui_ImplWin32_Data* bd = ImGui_ImplWin32_GetBackendData();
+    if (ImGui_ImplWin32_ViewportData* vd = (ImGui_ImplWin32_ViewportData*)viewport->PlatformUserData)
+    {
+        if (::GetCapture() == vd->Hwnd)
+        {
+            // Transfer capture so if we started dragging from a window that later disappears, we'll still receive the MOUSEUP event.
+            ::ReleaseCapture();
+            ::SetCapture(bd->hWnd);
+        }
+        if (vd->Hwnd && vd->HwndOwned)
+            ::DestroyWindow(vd->Hwnd);
+        vd->Hwnd = nullptr;
+        IM_DELETE(vd);
+    }
+    viewport->PlatformUserData = viewport->PlatformHandle = nullptr;
+}
+
+static void ImGui_ImplWin32_ShowWindow(ImGuiViewport* viewport)
+{
+    ImGui_ImplWin32_ViewportData* vd = (ImGui_ImplWin32_ViewportData*)viewport->PlatformUserData;
+    IM_ASSERT(vd->Hwnd != 0);
+
+    // ShowParent() also brings parent to front, which is not always desirable,
+    // so we temporarily disable parenting. (#7354)
+    if (vd->HwndParent != NULL)
+        ::SetWindowLongPtr(vd->Hwnd, GWLP_HWNDPARENT, (LONG_PTR)nullptr);
+
+    if (viewport->Flags & ImGuiViewportFlags_NoFocusOnAppearing)
+        ::ShowWindow(vd->Hwnd, SW_SHOWNA);
+    else
+        ::ShowWindow(vd->Hwnd, SW_SHOW);
+
+    // Restore
+    if (vd->HwndParent != NULL)
+        ::SetWindowLongPtr(vd->Hwnd, GWLP_HWNDPARENT, (LONG_PTR)vd->HwndParent);
+}
+
+static void ImGui_ImplWin32_UpdateWindow(ImGuiViewport* viewport)
+{
+    ImGui_ImplWin32_ViewportData* vd = (ImGui_ImplWin32_ViewportData*)viewport->PlatformUserData;
+    IM_ASSERT(vd->Hwnd != 0);
+
+    // Update Win32 parent if it changed _after_ creation
+    // Unlike style settings derived from configuration flags, this is more likely to change for advanced apps that are manipulating ParentViewportID manually.
+    HWND new_parent = ImGui_ImplWin32_GetHwndFromViewportID(viewport->ParentViewportId);
+    if (new_parent != vd->HwndParent)
+    {
+        // Win32 windows can either have a "Parent" (for WS_CHILD window) or an "Owner" (which among other thing keeps window above its owner).
+        // Our Dear Imgui-side concept of parenting only mostly care about what Win32 call "Owner".
+        // The parent parameter of CreateWindowEx() sets up Parent OR Owner depending on WS_CHILD flag. In our case an Owner as we never use WS_CHILD.
+        // Calling ::SetParent() here would be incorrect: it will create a full child relation, alter coordinate system and clipping.
+        // Calling ::SetWindowLongPtr() with GWLP_HWNDPARENT seems correct although poorly documented.
+        // https://devblogs.microsoft.com/oldnewthing/20100315-00/?p=14613
+        vd->HwndParent = new_parent;
+        ::SetWindowLongPtr(vd->Hwnd, GWLP_HWNDPARENT, (LONG_PTR)vd->HwndParent);
+    }
+
+    // (Optional) Update Win32 style if it changed _after_ creation.
+    // Generally they won't change unless configuration flags are changed, but advanced uses (such as manually rewriting viewport flags) make this useful.
+    DWORD new_style;
+    DWORD new_ex_style;
+    ImGui_ImplWin32_GetWin32StyleFromViewportFlags(viewport->Flags, &new_style, &new_ex_style);
+
+    // Only reapply the flags that have been changed from our point of view (as other flags are being modified by Windows)
+    if (vd->DwStyle != new_style || vd->DwExStyle != new_ex_style)
+    {
+        // (Optional) Update TopMost state if it changed _after_ creation
+        bool top_most_changed = (vd->DwExStyle & WS_EX_TOPMOST) != (new_ex_style & WS_EX_TOPMOST);
+        HWND insert_after = top_most_changed ? ((viewport->Flags & ImGuiViewportFlags_TopMost) ? HWND_TOPMOST : HWND_NOTOPMOST) : 0;
+        UINT swp_flag = top_most_changed ? 0 : SWP_NOZORDER;
+
+        // Apply flags and position (since it is affected by flags)
+        vd->DwStyle = new_style;
+        vd->DwExStyle = new_ex_style;
+        ::SetWindowLong(vd->Hwnd, GWL_STYLE, vd->DwStyle);
+        ::SetWindowLong(vd->Hwnd, GWL_EXSTYLE, vd->DwExStyle);
+        RECT rect = { (LONG)viewport->Pos.x, (LONG)viewport->Pos.y, (LONG)(viewport->Pos.x + viewport->Size.x), (LONG)(viewport->Pos.y + viewport->Size.y) };
+        ::AdjustWindowRectEx(&rect, vd->DwStyle, FALSE, vd->DwExStyle); // Client to Screen
+        ::SetWindowPos(vd->Hwnd, insert_after, rect.left, rect.top, rect.right - rect.left, rect.bottom - rect.top, swp_flag | SWP_NOACTIVATE | SWP_FRAMECHANGED);
+        ::ShowWindow(vd->Hwnd, SW_SHOWNA); // This is necessary when we alter the style
+        viewport->PlatformRequestMove = viewport->PlatformRequestResize = true;
+    }
+}
+
+static ImVec2 ImGui_ImplWin32_GetWindowPos(ImGuiViewport* viewport)
+{
+    ImGui_ImplWin32_ViewportData* vd = (ImGui_ImplWin32_ViewportData*)viewport->PlatformUserData;
+    IM_ASSERT(vd->Hwnd != 0);
+    POINT pos = { 0, 0 };
+    ::ClientToScreen(vd->Hwnd, &pos);
+    return ImVec2((float)pos.x, (float)pos.y);
+}
+
+static void ImGui_ImplWin32_UpdateWin32StyleFromWindow(ImGuiViewport* viewport)
+{
+    ImGui_ImplWin32_ViewportData* vd = (ImGui_ImplWin32_ViewportData*)viewport->PlatformUserData;
+    vd->DwStyle = ::GetWindowLongW(vd->Hwnd, GWL_STYLE);
+    vd->DwExStyle = ::GetWindowLongW(vd->Hwnd, GWL_EXSTYLE);
+}
+
+static void ImGui_ImplWin32_SetWindowPos(ImGuiViewport* viewport, ImVec2 pos)
+{
+    ImGui_ImplWin32_ViewportData* vd = (ImGui_ImplWin32_ViewportData*)viewport->PlatformUserData;
+    IM_ASSERT(vd->Hwnd != 0);
+    RECT rect = { (LONG)pos.x, (LONG)pos.y, (LONG)pos.x, (LONG)pos.y };
+    if (viewport->Flags & ImGuiViewportFlags_OwnedByApp)
+        ImGui_ImplWin32_UpdateWin32StyleFromWindow(viewport); // Not our window, poll style before using
+    ::AdjustWindowRectEx(&rect, vd->DwStyle, FALSE, vd->DwExStyle);
+    ::SetWindowPos(vd->Hwnd, nullptr, rect.left, rect.top, 0, 0, SWP_NOZORDER | SWP_NOSIZE | SWP_NOACTIVATE);
+}
+
+static ImVec2 ImGui_ImplWin32_GetWindowSize(ImGuiViewport* viewport)
+{
+    ImGui_ImplWin32_ViewportData* vd = (ImGui_ImplWin32_ViewportData*)viewport->PlatformUserData;
+    IM_ASSERT(vd->Hwnd != 0);
+    RECT rect;
+    ::GetClientRect(vd->Hwnd, &rect);
+    return ImVec2(float(rect.right - rect.left), float(rect.bottom - rect.top));
+}
+
+static void ImGui_ImplWin32_SetWindowSize(ImGuiViewport* viewport, ImVec2 size)
+{
+    ImGui_ImplWin32_ViewportData* vd = (ImGui_ImplWin32_ViewportData*)viewport->PlatformUserData;
+    IM_ASSERT(vd->Hwnd != 0);
+    RECT rect = { 0, 0, (LONG)size.x, (LONG)size.y };
+    if (viewport->Flags & ImGuiViewportFlags_OwnedByApp)
+        ImGui_ImplWin32_UpdateWin32StyleFromWindow(viewport); // Not our window, poll style before using
+    ::AdjustWindowRectEx(&rect, vd->DwStyle, FALSE, vd->DwExStyle); // Client to Screen
+    ::SetWindowPos(vd->Hwnd, nullptr, 0, 0, rect.right - rect.left, rect.bottom - rect.top, SWP_NOZORDER | SWP_NOMOVE | SWP_NOACTIVATE);
+}
+
+static void ImGui_ImplWin32_SetWindowFocus(ImGuiViewport* viewport)
+{
+    ImGui_ImplWin32_ViewportData* vd = (ImGui_ImplWin32_ViewportData*)viewport->PlatformUserData;
+    IM_ASSERT(vd->Hwnd != 0);
+    ::BringWindowToTop(vd->Hwnd);
+    ::SetForegroundWindow(vd->Hwnd);
+    ::SetFocus(vd->Hwnd);
+}
+
+static bool ImGui_ImplWin32_GetWindowFocus(ImGuiViewport* viewport)
+{
+    ImGui_ImplWin32_ViewportData* vd = (ImGui_ImplWin32_ViewportData*)viewport->PlatformUserData;
+    IM_ASSERT(vd->Hwnd != 0);
+    return ::GetForegroundWindow() == vd->Hwnd;
+}
+
+static bool ImGui_ImplWin32_GetWindowMinimized(ImGuiViewport* viewport)
+{
+    ImGui_ImplWin32_ViewportData* vd = (ImGui_ImplWin32_ViewportData*)viewport->PlatformUserData;
+    IM_ASSERT(vd->Hwnd != 0);
+    return ::IsIconic(vd->Hwnd) != 0;
+}
+
+static void ImGui_ImplWin32_SetWindowTitle(ImGuiViewport* viewport, const char* title)
+{
+    // ::SetWindowTextA() doesn't properly handle UTF-8 so we explicitely convert our string.
+    ImGui_ImplWin32_ViewportData* vd = (ImGui_ImplWin32_ViewportData*)viewport->PlatformUserData;
+    IM_ASSERT(vd->Hwnd != 0);
+    int n = ::MultiByteToWideChar(CP_UTF8, 0, title, -1, nullptr, 0);
+    ImVector<wchar_t> title_w;
+    title_w.resize(n);
+    ::MultiByteToWideChar(CP_UTF8, 0, title, -1, title_w.Data, n);
+    ::SetWindowTextW(vd->Hwnd, title_w.Data);
+}
+
+static void ImGui_ImplWin32_SetWindowAlpha(ImGuiViewport* viewport, float alpha)
+{
+    ImGui_ImplWin32_ViewportData* vd = (ImGui_ImplWin32_ViewportData*)viewport->PlatformUserData;
+    IM_ASSERT(vd->Hwnd != 0);
+    IM_ASSERT(alpha >= 0.0f && alpha <= 1.0f);
+    if (alpha < 1.0f)
+    {
+        DWORD ex_style = ::GetWindowLongW(vd->Hwnd, GWL_EXSTYLE) | WS_EX_LAYERED;
+        ::SetWindowLongW(vd->Hwnd, GWL_EXSTYLE, ex_style);
+        ::SetLayeredWindowAttributes(vd->Hwnd, 0, (BYTE)(255 * alpha), LWA_ALPHA);
+    }
+    else
+    {
+        DWORD ex_style = ::GetWindowLongW(vd->Hwnd, GWL_EXSTYLE) & ~WS_EX_LAYERED;
+        ::SetWindowLongW(vd->Hwnd, GWL_EXSTYLE, ex_style);
+    }
+}
+
+static float ImGui_ImplWin32_GetWindowDpiScale(ImGuiViewport* viewport)
+{
+    ImGui_ImplWin32_ViewportData* vd = (ImGui_ImplWin32_ViewportData*)viewport->PlatformUserData;
+    IM_ASSERT(vd->Hwnd != 0);
+    return ImGui_ImplWin32_GetDpiScaleForHwnd(vd->Hwnd);
+}
+
+// FIXME-DPI: Testing DPI related ideas
+static void ImGui_ImplWin32_OnChangedViewport(ImGuiViewport* viewport)
+{
+    (void)viewport;
+#if 0
+    ImGuiStyle default_style;
+    //default_style.WindowPadding = ImVec2(0, 0);
+    //default_style.WindowBorderSize = 0.0f;
+    //default_style.ItemSpacing.y = 3.0f;
+    //default_style.FramePadding = ImVec2(0, 0);
+    default_style.ScaleAllSizes(viewport->DpiScale);
+    ImGuiStyle& style = ImGui::GetStyle();
+    style = default_style;
+#endif
+}
+
+namespace ImGui { extern ImGuiIO& GetIOEx(ImGuiContext*); extern ImGuiPlatformIO& GetPlatformIOEx(ImGuiContext*); }
+
+static LRESULT CALLBACK ImGui_ImplWin32_WndProcHandler_PlatformWindow(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)
+{
+    // Allow secondary viewport WndProc to be called regardless of current context
+    ImGuiContext* ctx = (ImGuiContext*)::GetPropA(hWnd, "IMGUI_CONTEXT");
+    if (ctx == NULL)
+        return DefWindowProc(hWnd, msg, wParam, lParam); // unlike ImGui_ImplWin32_WndProcHandler() we are called directly by Windows, we can't just return 0.
+
+    ImGuiIO& io = ImGui::GetIOEx(ctx);
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIOEx(ctx);
+    LRESULT result = 0;
+    if (ImGui_ImplWin32_WndProcHandlerEx(hWnd, msg, wParam, lParam, io))
+        result = true;
+    else if (ImGuiViewport* viewport = ImGui_ImplWin32_FindViewportByPlatformHandle(platform_io, hWnd))
+    {
+        switch (msg)
+        {
+        case WM_CLOSE:
+            viewport->PlatformRequestClose = true;
+            break;
+        case WM_MOVE:
+            viewport->PlatformRequestMove = true;
+            break;
+        case WM_SIZE:
+            viewport->PlatformRequestResize = true;
+            break;
+        case WM_MOUSEACTIVATE:
+            if (viewport->Flags & ImGuiViewportFlags_NoFocusOnClick)
+                result = MA_NOACTIVATE;
+            break;
+        case WM_NCHITTEST:
+            // Let mouse pass-through the window. This will allow the backend to call io.AddMouseViewportEvent() correctly. (which is optional).
+            // The ImGuiViewportFlags_NoInputs flag is set while dragging a viewport, as want to detect the window behind the one we are dragging.
+            // If you cannot easily access those viewport flags from your windowing/event code: you may manually synchronize its state e.g. in
+            // your main loop after calling UpdatePlatformWindows(). Iterate all viewports/platform windows and pass the flag to your windowing system.
+            if (viewport->Flags & ImGuiViewportFlags_NoInputs)
+                result = HTTRANSPARENT;
+            break;
+        }
+    }
+    if (result == 0)
+        result = DefWindowProc(hWnd, msg, wParam, lParam);
+    return result;
+}
+
+static void ImGui_ImplWin32_InitMultiViewportSupport(bool platform_has_own_dc)
+{
+    WNDCLASSEXW wcex;
+    wcex.cbSize = sizeof(WNDCLASSEXW);
+    wcex.style = CS_HREDRAW | CS_VREDRAW | (platform_has_own_dc ? CS_OWNDC : 0);
+    wcex.lpfnWndProc = ImGui_ImplWin32_WndProcHandler_PlatformWindow;
+    wcex.cbClsExtra = 0;
+    wcex.cbWndExtra = 0;
+    wcex.hInstance = ::GetModuleHandle(nullptr);
+    wcex.hIcon = nullptr;
+    wcex.hCursor = nullptr;
+    wcex.hbrBackground = (HBRUSH)(COLOR_BACKGROUND + 1);
+    wcex.lpszMenuName = nullptr;
+    wcex.lpszClassName = L"ImGui Platform";
+    wcex.hIconSm = nullptr;
+    ::RegisterClassExW(&wcex);
+
+    ImGui_ImplWin32_UpdateMonitors();
+
+    // Register platform interface (will be coupled with a renderer interface)
+    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
+    platform_io.Platform_CreateWindow = ImGui_ImplWin32_CreateWindow;
+    platform_io.Platform_DestroyWindow = ImGui_ImplWin32_DestroyWindow;
+    platform_io.Platform_ShowWindow = ImGui_ImplWin32_ShowWindow;
+    platform_io.Platform_SetWindowPos = ImGui_ImplWin32_SetWindowPos;
+    platform_io.Platform_GetWindowPos = ImGui_ImplWin32_GetWindowPos;
+    platform_io.Platform_SetWindowSize = ImGui_ImplWin32_SetWindowSize;
+    platform_io.Platform_GetWindowSize = ImGui_ImplWin32_GetWindowSize;
+    platform_io.Platform_SetWindowFocus = ImGui_ImplWin32_SetWindowFocus;
+    platform_io.Platform_GetWindowFocus = ImGui_ImplWin32_GetWindowFocus;
+    platform_io.Platform_GetWindowMinimized = ImGui_ImplWin32_GetWindowMinimized;
+    platform_io.Platform_SetWindowTitle = ImGui_ImplWin32_SetWindowTitle;
+    platform_io.Platform_SetWindowAlpha = ImGui_ImplWin32_SetWindowAlpha;
+    platform_io.Platform_UpdateWindow = ImGui_ImplWin32_UpdateWindow;
+    platform_io.Platform_GetWindowDpiScale = ImGui_ImplWin32_GetWindowDpiScale; // FIXME-DPI
+    platform_io.Platform_OnChangedViewport = ImGui_ImplWin32_OnChangedViewport; // FIXME-DPI
+
+    // Register main window handle (which is owned by the main application, not by us)
+    // This is mostly for simplicity and consistency, so that our code (e.g. mouse handling etc.) can use same logic for main and secondary viewports.
+    ImGuiViewport* main_viewport = ImGui::GetMainViewport();
+    ImGui_ImplWin32_Data* bd = ImGui_ImplWin32_GetBackendData();
+    ImGui_ImplWin32_ViewportData* vd = IM_NEW(ImGui_ImplWin32_ViewportData)();
+    vd->Hwnd = bd->hWnd;
+    vd->HwndOwned = false;
+    main_viewport->PlatformUserData = vd;
+}
+
+static void ImGui_ImplWin32_ShutdownMultiViewportSupport()
+{
+    ::UnregisterClass(_T("ImGui Platform"), ::GetModuleHandle(nullptr));
+    ImGui::DestroyPlatformWindows();
+}
+
 //---------------------------------------------------------------------------------------------------------
 
 #if defined(__GNUC__)

backends/imgui_impl_win32.h

@@ -4,9 +4,10 @@
 // Implemented features:
 //  [X] Platform: Clipboard support (for Win32 this is actually part of core dear imgui)
 //  [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen/Pen.
-//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy VK_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
+//  [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy VK_* values are obsolete since 1.87 and not supported since 1.91.5]
 //  [X] Platform: Gamepad support. Enabled with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
-//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+//  [X] Platform: Mouse cursor shape and visibility (ImGuiBackendFlags_HasMouseCursors). Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+//  [X] Platform: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
 // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
@@ -20,6 +21,7 @@
 #include "imgui.h"      // IMGUI_IMPL_API
 #ifndef IMGUI_DISABLE
 
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
 IMGUI_IMPL_API bool     ImGui_ImplWin32_Init(void* hwnd);
 IMGUI_IMPL_API bool     ImGui_ImplWin32_InitForOpenGL(void* hwnd);
 IMGUI_IMPL_API void     ImGui_ImplWin32_Shutdown();

docs/BACKENDS.md

@@ -2,23 +2,10 @@ _(You may browse this at https://github.com/ocornut/imgui/blob/master/docs/BACKE
 
 ## Dear ImGui: Backends
 
-**The backends/ folder contains backends for popular platforms/graphics API, which you can use in
-your application or engine to easily integrate Dear ImGui.** Each backend is typically self-contained in a pair of files: imgui_impl_XXXX.cpp + imgui_impl_XXXX.h.
-
-- The 'Platform' backends are in charge of: mouse/keyboard/gamepad inputs, cursor shape, timing, and windowing.<BR>
-  e.g. Windows ([imgui_impl_win32.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_win32.cpp)), GLFW ([imgui_impl_glfw.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_glfw.cpp)), SDL2 ([imgui_impl_sdl2.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_sdl2.cpp)), etc.
-
-- The 'Renderer' backends are in charge of: creating atlas texture, and rendering imgui draw data.<BR>
-  e.g. DirectX11 ([imgui_impl_dx11.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_dx11.cpp)), OpenGL/WebGL ([imgui_impl_opengl3.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_opengl3.cpp)), Vulkan ([imgui_impl_vulkan.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_vulkan.cpp)), etc.
-
-- For some high-level frameworks, a single backend usually handles both 'Platform' and 'Renderer' parts.<BR>
-  e.g. Allegro 5 ([imgui_impl_allegro5.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_allegro5.cpp)). If you end up creating a custom backend for your engine, you may want to do the same.
-
-An application usually combines one Platform backend + one Renderer backend + main Dear ImGui sources.
-For example, the [example_win32_directx11](https://github.com/ocornut/imgui/tree/master/examples/example_win32_directx11) application combines imgui_impl_win32.cpp + imgui_impl_dx11.cpp. There are 20+ examples in the [examples/](https://github.com/ocornut/imgui/blob/master/examples/) folder. See [EXAMPLES.MD](https://github.com/ocornut/imgui/blob/master/docs/EXAMPLES.md) for details.
-
-**Once Dear ImGui is setup and running, run and refer to `ImGui::ShowDemoWindow()` in imgui_demo.cpp for usage of the end-user API.**
+### Integrating backends
 
+💡 The **[Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started) wiki guide** has examples of how to integrate Dear ImGui into an existing application.
+<BR> The [EXAMPLES.MD](https://github.com/ocornut/imgui/blob/master/docs/EXAMPLES.md) documentation may also be worth a read.
 
 ### What are backends?
 
@@ -38,7 +25,7 @@ Dear ImGui is highly portable and only requires a few things to run and render,
  - Optional: multi-viewports support.
  etc.
 
-This is essentially what each backend is doing + obligatory portability cruft. Using default backends ensure you can get all those features including the ones that would be harder to implement on your side (e.g. multi-viewports support).
+This is essentially what each backend is doing + obligatory portability cruft. Using standard backends ensure you can get all those features including the ones that would be harder to implement on your side (e.g. multi-viewports support).
 
 It is important to understand the difference between the core Dear ImGui library (files in the root folder)
 and the backends which we are describing here (backends/ folder).
@@ -47,11 +34,24 @@ and the backends which we are describing here (backends/ folder).
 - You should be able to write backends for pretty much any platform and any 3D graphics API.
   e.g. you can get creative and use software rendering or render remotely on a different machine.
 
+### Standard backends
 
-### Integrating a backend
+**The [backends/](https://github.com/ocornut/imgui/blob/master/backends) folder contains backends for popular platforms/graphics API, which you can use in
+your application or engine to easily integrate Dear ImGui.** Each backend is typically self-contained in a pair of files: imgui_impl_XXXX.cpp + imgui_impl_XXXX.h.
 
-See "Getting Started" section of [EXAMPLES.MD](https://github.com/ocornut/imgui/blob/master/docs/EXAMPLES.md) for more details.
+- The 'Platform' backends are in charge of: mouse/keyboard/gamepad inputs, cursor shape, timing, and windowing.<BR>
+  e.g. Windows ([imgui_impl_win32.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_win32.cpp)), GLFW ([imgui_impl_glfw.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_glfw.cpp)), SDL2 ([imgui_impl_sdl2.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_sdl2.cpp)), etc.
 
+- The 'Renderer' backends are in charge of: creating atlas texture, and rendering imgui draw data.<BR>
+  e.g. DirectX11 ([imgui_impl_dx11.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_dx11.cpp)), OpenGL/WebGL ([imgui_impl_opengl3.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_opengl3.cpp)), Vulkan ([imgui_impl_vulkan.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_vulkan.cpp)), etc.
+
+- For some high-level frameworks, a single backend usually handles both 'Platform' and 'Renderer' parts.<BR>
+  e.g. Allegro 5 ([imgui_impl_allegro5.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_allegro5.cpp)). If you end up creating a custom backend for your engine, you may want to do the same.
+
+An application usually combines one Platform backend + one Renderer backend + main Dear ImGui sources.
+For example, the [example_win32_directx11](https://github.com/ocornut/imgui/tree/master/examples/example_win32_directx11) application combines imgui_impl_win32.cpp + imgui_impl_dx11.cpp. There are 20+ examples in the [examples/](https://github.com/ocornut/imgui/blob/master/examples/) folder. See [EXAMPLES.MD](https://github.com/ocornut/imgui/blob/master/docs/EXAMPLES.md) for details.
+
+**Once Dear ImGui is setup and running, run and refer to `ImGui::ShowDemoWindow()` in imgui_demo.cpp for usage of the end-user API.**
 
 ### List of backends
 
@@ -135,7 +135,7 @@ Generally:
 It is unlikely you will add value to your project by creating your own backend.
 
 Also:
-The [multi-viewports feature](https://github.com/ocornut/imgui/issues/1542) of the 'docking' branch allows
+The [multi-viewports feature](https://github.com/ocornut/imgui/wiki/Multi-Viewports) of the 'docking' branch allows
 Dear ImGui windows to be seamlessly detached from the main application window. This is achieved using an
 extra layer to the Platform and Renderer backends, which allows Dear ImGui to communicate platform-specific
 requests such as: "create an additional OS window", "create a render context", "get the OS position of this

docs/EXAMPLES.md

@@ -35,46 +35,13 @@ At shutdown:
   call ImGui::DestroyContext()
 ```
 
-Example (using [backends/imgui_impl_win32.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_win32.cpp) + [backends/imgui_impl_dx11.cpp](https://github.com/ocornut/imgui/blob/master/backends/imgui_impl_dx11.cpp)):
+Main resource:
+- Read **[Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started) wiki guide** for detailed examples of how to integrate Dear ImGui in an existing application.
 
-```cpp
-// Create a Dear ImGui context, setup some options
-ImGui::CreateContext();
-ImGuiIO& io = ImGui::GetIO();
-io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard; // Enable some options
-
-// Initialize Platform + Renderer backends (here: using imgui_impl_win32.cpp + imgui_impl_dx11.cpp)
-ImGui_ImplWin32_Init(my_hwnd);
-ImGui_ImplDX11_Init(my_d3d_device, my_d3d_device_context);
-
-// Application main loop
-while (true)
-{
-    // Beginning of frame: update Renderer + Platform backend, start Dear ImGui frame
-    ImGui_ImplDX11_NewFrame();
-    ImGui_ImplWin32_NewFrame();
-    ImGui::NewFrame();
-
-    // Any application code here
-    ImGui::Text("Hello, world!");
-
-    // End of frame: render Dear ImGui
-    ImGui::Render();
-    ImGui_ImplDX11_RenderDrawData(ImGui::GetDrawData());
-
-    // Swap
-    g_pSwapChain->Present(1, 0);
-}
-
-// Shutdown
-ImGui_ImplDX11_Shutdown();
-ImGui_ImplWin32_Shutdown();
-ImGui::DestroyContext();
-```
-
-Please read 'PROGRAMMER GUIDE' in imgui.cpp for notes on how to setup Dear ImGui in your codebase.
-Please read the comments and instruction at the top of each file.
-Please read FAQ at https://www.dearimgui.com/faq
+Additional resources:
+- Read FAQ at https://www.dearimgui.com/faq
+- Read 'PROGRAMMER GUIDE' section in imgui.cpp.
+- Read the comments and instruction at the top of each file.
 
 If you are using any of the backends provided here, you can add the backends/imgui_impl_xxxx(.cpp,.h)
 files to your project and use as-in. Each imgui_impl_xxxx.cpp file comes with its own individual

docs/FAQ.md

@@ -77,9 +77,9 @@ or view this file with any Markdown viewer.
 ### Q: Which version should I get?
 I occasionally tag [Releases](https://github.com/ocornut/imgui/releases) but it is generally safe and recommended to sync to master/latest. The library is fairly stable and regressions tend to be fixed fast when reported.
 
-You may use the [docking](https://github.com/ocornut/imgui/tree/docking) branch which includes:
-- [Docking features](https://github.com/ocornut/imgui/issues/2109)
-- [Multi-viewport features](https://github.com/ocornut/imgui/issues/1542)
+You may use the ['docking'](https://github.com/ocornut/imgui/tree/docking) branch which includes:
+- [Docking features](https://github.com/ocornut/imgui/wiki/Docking)
+- [Multi-viewport features](https://github.com/ocornut/imgui/wiki/Multi-Viewports)
 
 Many projects are using this branch and it is kept in sync with master regularly.
 
@@ -204,10 +204,11 @@ ctx->RSSetScissorRects(1, &r);
 ### Q: How can I have multiple widgets with the same label?
 ### Q: How can I have multiple windows with the same label?
 
-**USING THE SAME LABEL+ID IS THE MOST COMMON USER MISTAKE:**
+**USING THE SAME LABEL+ID IS THE MOST COMMON USER MISTAKE!**
+<br>**USING AN EMPTY LABEL IS THE SAME AS USING THE SAME LABEL AS YOUR PARENT WIDGET!**
 <table>
 <tr>
-<td><img src="https://github.com/ocornut/imgui/assets/8225057/76eb9467-74d1-4e95-9f56-be81c6dd029d"></td>
+<td><img src="https://github.com/user-attachments/assets/776a8315-1164-4178-9a8c-df52e0ff28aa"></td>
 <td>
 <pre lang="cpp">
 ImGui::Begin("Incorrect!");
@@ -379,8 +380,9 @@ node open/closed state differently. See what makes more sense in your situation!
 Short explanation:
 - Refer to [Image Loading and Displaying Examples](https://github.com/ocornut/imgui/wiki/Image-Loading-and-Displaying-Examples) on the [Wiki](https://github.com/ocornut/imgui/wiki).
 - You may use functions such as `ImGui::Image()`, `ImGui::ImageButton()` or lower-level `ImDrawList::AddImage()` to emit draw calls that will use your own textures.
-- Actual textures are identified in a way that is up to the user/engine. Those identifiers are stored and passed as ImTextureID (void*) value.
-- Loading image files from the disk and turning them into a texture is not within the scope of Dear ImGui (for a good reason).
+- Actual textures are identified in a way that is up to the user/engine. Those identifiers are stored and passed as an opaque ImTextureID value.
+- By default ImTextureID can store up to 64-bits. You may `#define` it to a custom type/structure if you need.
+- Loading image files from the disk and turning them into a texture is not within the scope of Dear ImGui (for a good reason), but the examples linked above may be useful references.
 
 **Please read documentations or tutorials on your graphics API to understand how to display textures on the screen before moving onward.**
 
@@ -388,27 +390,27 @@ Long explanation:
 - Dear ImGui's job is to create "meshes", defined in a renderer-agnostic format made of draw commands and vertices. At the end of the frame, those meshes (ImDrawList) will be displayed by your rendering function. They are made up of textured polygons and the code to render them is generally fairly short (a few dozen lines). In the examples/ folder, we provide functions for popular graphics APIs (OpenGL, DirectX, etc.).
 - Each rendering function decides on a data type to represent "textures". The concept of what is a "texture" is entirely tied to your underlying engine/graphics API.
  We carry the information to identify a "texture" in the ImTextureID type.
-ImTextureID is nothing more than a void*, aka 4/8 bytes worth of data: just enough to store one pointer or integer of your choice.
+ImTextureID default to ImU64 aka 8 bytes worth of data: just enough to store one pointer or integer of your choice.
 Dear ImGui doesn't know or understand what you are storing in ImTextureID, it merely passes ImTextureID values until they reach your rendering function.
 - In the [examples/](https://github.com/ocornut/imgui/tree/master/examples) backends, for each graphics API we decided on a type that is likely to be a good representation for specifying an image from the end-user perspective. This is what the _examples_ rendering functions are using:
 ```cpp
 OpenGL:
-- ImTextureID = GLuint
+- ImTextureID should contains 'GLuint' (GL texture identifier).
 - See ImGui_ImplOpenGL3_RenderDrawData() function in imgui_impl_opengl3.cpp
 ```
 ```cpp
 DirectX9:
-- ImTextureID = LPDIRECT3DTEXTURE9
+- ImTextureID should contain a 'LPDIRECT3DTEXTURE9' (pointer).
 - See ImGui_ImplDX9_RenderDrawData() function in imgui_impl_dx9.cpp
 ```
 ```cpp
 DirectX11:
-- ImTextureID = ID3D11ShaderResourceView*
+- ImTextureID should contain a 'ID3D11ShaderResourceView*' (pointer)
 - See ImGui_ImplDX11_RenderDrawData() function in imgui_impl_dx11.cpp
 ```
 ```cpp
 DirectX12:
-- ImTextureID = D3D12_GPU_DESCRIPTOR_HANDLE
+- ImTextureID should contain a 'D3D12_GPU_DESCRIPTOR_HANDLE' (always 64-bits)
 - See ImGui_ImplDX12_RenderDrawData() function in imgui_impl_dx12.cpp
 ```
 For example, in the OpenGL example backend we store raw OpenGL texture identifier (GLuint) inside ImTextureID.
@@ -420,14 +422,14 @@ If you are starting with OpenGL or DirectX or Vulkan and haven't built much of a
 
 User code may do:
 ```cpp
-// Cast our texture type to ImTextureID / void*
+// Cast our texture type to ImTextureID
 MyTexture* texture = g_CoffeeTableTexture;
-ImGui::Image((void*)texture, ImVec2(texture->Width, texture->Height));
+ImGui::Image((ImTextureID)(intptr_t)texture, ImVec2(texture->Width, texture->Height));
 ```
 The renderer function called after ImGui::Render() will receive that same value that the user code passed:
 ```cpp
-// Cast ImTextureID / void* stored in the draw command as our texture type
-MyTexture* texture = (MyTexture*)pcmd->GetTexID();
+// Cast ImTextureID stored in the draw command as our texture type
+MyTexture* texture = (MyTexture*)(intptr_t)pcmd->GetTexID();
 MyEngineBindTexture2D(texture);
 ```
 Once you understand this design, you will understand that loading image files and turning them into displayable textures is not within the scope of Dear ImGui.
@@ -436,19 +438,19 @@ If you want to display an image file (e.g. PNG file) on the screen, please refer
 
 Refer to [Image Loading and Displaying Examples](https://github.com/ocornut/imgui/wiki/Image-Loading-and-Displaying-Examples) on the [Wiki](https://github.com/ocornut/imgui/wiki) to find simplified examples for loading textures with OpenGL, DirectX9 and DirectX11.
 
-C/C++ tip: a void* is pointer-sized storage. You may safely store any pointer or integer into it by casting your value to ImTextureID / void*, and vice-versa.
-Because both end-points (user code and rendering function) are under your control, you know exactly what is stored inside the ImTextureID / void*.
+C/C++ tip: a u64 is 8 bytes. You may safely store any pointer or integer into it by casting your value to ImTextureID, and vice-versa.
+Because both end-points (user code and rendering function) are under your control, you know exactly what is stored inside the ImTextureID.
 Here are some examples:
 ```cpp
 GLuint my_tex = XXX;
-void* my_void_ptr;
-my_void_ptr = (void*)(intptr_t)my_tex;                  // cast a GLuint into a void* (we don't take its address! we literally store the value inside the pointer)
-my_tex = (GLuint)(intptr_t)my_void_ptr;                 // cast a void* into a GLuint
+ImTextureID my_imtexid;
+my_imtexid = (ImTextureID)(intptr_t)my_tex;                     // cast a GLuint into a ImTextureID (we don't take its address! we just copy the address)
+my_tex = (GLuint)(intptr_t)my_imtexid;                          // cast a ImTextureID into a GLuint
 
 ID3D11ShaderResourceView* my_dx11_srv = XXX;
-void* my_void_ptr;
-my_void_ptr = (void*)my_dx11_srv;                       // cast a ID3D11ShaderResourceView* into an opaque void*
-my_dx11_srv = (ID3D11ShaderResourceView*)my_void_ptr;   // cast a void* into a ID3D11ShaderResourceView*
+ImTextureID my_imtexid;
+my_imtexid = (ImTextureID)(intptr_t)my_dx11_srv;                // cast a ID3D11ShaderResourceView* into an opaque ImTextureID
+my_dx11_srv = (ID3D11ShaderResourceView*)(intptr_t)_my_imtexid; // cast a ImTextureID into a ID3D11ShaderResourceView*
 ```
 Finally, you may call `ImGui::ShowMetricsWindow()` to explore/visualize/understand how the ImDrawList are generated.
 
@@ -639,7 +641,7 @@ The applications in examples/ are doing that.
 Windows: you can use the WM_CHAR or WM_UNICHAR or WM_IME_CHAR message (depending if your app is built using Unicode or MultiByte mode).
 You may also use `MultiByteToWideChar()` or `ToUnicode()` to retrieve Unicode codepoints from MultiByte characters or keyboard state.
 Windows: if your language is relying on an Input Method Editor (IME), you can write your HWND to ImGui::GetMainViewport()->PlatformHandleRaw
-for the default implementation of io.SetPlatformImeDataFn() to set your Microsoft IME position correctly.
+for the default implementation of GetPlatformIO().Platform_SetImeDataFn() to set your Microsoft IME position correctly.
 
 ##### [Return to Index](#index)
 
@@ -654,7 +656,7 @@ You may take a look at:
 - [Quotes](https://github.com/ocornut/imgui/wiki/Quotes)
 - [Software using Dear ImGui](https://github.com/ocornut/imgui/wiki/Software-using-dear-imgui)
 - [Funding & Sponsors](https://github.com/ocornut/imgui/wiki/Funding)
-- [Gallery](https://github.com/ocornut/imgui/issues/7503)
+- [Gallery](https://github.com/ocornut/imgui/issues?q=label%3Agallery)
 
 ##### [Return to Index](#index)
 
@@ -700,7 +702,7 @@ There is an auto-generated [c-api for Dear ImGui (cimgui)](https://github.com/ci
 - Individuals: you can support continued maintenance and development via PayPal donations. See [README](https://github.com/ocornut/imgui/blob/master/docs/README.md).
 - If you are experienced with Dear ImGui and C++, look at [GitHub Issues](https://github.com/ocornut/imgui/issues), [GitHub Discussions](https://github.com/ocornut/imgui/discussions), the [Wiki](https://github.com/ocornut/imgui/wiki), read [docs/TODO.txt](https://github.com/ocornut/imgui/blob/master/docs/TODO.txt), and see how you want to help and can help!
 - Disclose your usage of Dear ImGui via a dev blog post, a tweet, a screenshot, a mention somewhere, etc.
-You may post screenshots or links in the [gallery threads](https://github.com/ocornut/imgui/issues/7503). Visuals are ideal as they inspire other programmers. Disclosing your use of Dear ImGui helps the library grow credibility, and helps other teams and programmers with taking decisions.
+You may post screenshots or links in the [gallery threads](https://github.com/ocornut/imgui/issues?q=label%3Agallery). Visuals are ideal as they inspire other programmers. Disclosing your use of Dear ImGui helps the library grow credibility, and helps other teams and programmers with taking decisions.
 - If you have issues or if you need to hack into the library, even if you don't expect any support it is useful that you share your issues or sometimes incomplete PR.
 
 ##### [Return to Index](#index)

docs/FONTS.md

@@ -50,7 +50,9 @@ All loaded fonts glyphs are rendered into a single texture atlas ahead of time.
 
 ### (4) Font atlas texture fails to upload to GPU.
 
-This is often of byproduct of point 3. If you have large number of glyphs or multiple fonts, the texture may become too big for your graphics API. **The typical result of failing to upload a texture is if every glyph or everything appears as empty black or white rectangle.** Mind the fact that some graphics drivers have texture size limitation. If you are building a PC application, mind the fact that your users may use hardware with lower limitations than yours.
+This is often of byproduct of point 3. If you have large number of glyphs or multiple fonts, the texture may become too big for your graphics API. **The typical result of failing to upload a texture is if every glyph or everything appears as empty white rectangles.** Mind the fact that some graphics drivers have texture size limitation. If you are building a PC application, mind the fact that your users may use hardware with lower limitations than yours.
+
+![empty squares](https://github.com/user-attachments/assets/68b50fb5-8b9d-4c38-baec-6ac384f06d26)
 
 Some solutions:
 - You may reduce oversampling, e.g. `font_config.OversampleH = 1`, this will half your texture size for a quality loss.
@@ -60,6 +62,8 @@ Some solutions:
 - Set `io.Fonts.Flags |= ImFontAtlasFlags_NoPowerOfTwoHeight;` to disable rounding the texture height to the next power of two.
 - Set `io.Fonts.TexDesiredWidth` to specify a texture width to reduce maximum texture height (see comment in `ImFontAtlas::Build()` function).
 
+Future versions of Dear ImGui should solve this problem.
+
 ##### [Return to Index](#index)
 
 ---------------------------------------

docs/README.md

@@ -13,7 +13,7 @@ Businesses: support continued development and maintenance via invoiced sponsorin
 <br>&nbsp;&nbsp;_E-mail: contact @ dearimgui dot com_
 <br>Individuals: support continued development and maintenance [here](https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=WGHNC6MBFLZ2S). Also see [Funding](https://github.com/ocornut/imgui/wiki/Funding) page.
 
-| [The Pitch](#the-pitch) - [Usage](#usage) - [How it works](#how-it-works) - [Releases & Changelogs](#releases--changelogs) - [Demo](#demo) - [Integration](#integration) |
+| [The Pitch](#the-pitch) - [Usage](#usage) - [How it works](#how-it-works) - [Releases & Changelogs](#releases--changelogs) - [Demo](#demo) - [Getting Started & Integration](#getting-started--integration) |
 :----------------------------------------------------------: |
 | [Gallery](#gallery) - [Support, FAQ](#support-frequently-asked-questions-faq) -  [How to help](#how-to-help) - **[Funding & Sponsors](https://github.com/ocornut/imgui/wiki/Funding)** - [Credits](#credits) - [License](#license) |
 | [Wiki](https://github.com/ocornut/imgui/wiki) - [Extensions](https://github.com/ocornut/imgui/wiki/Useful-Extensions) - [Languages bindings & frameworks backends](https://github.com/ocornut/imgui/wiki/Bindings) - [Software using Dear ImGui](https://github.com/ocornut/imgui/wiki/Software-using-dear-imgui) - [User quotes](https://github.com/ocornut/imgui/wiki/Quotes) |
@@ -22,7 +22,7 @@ Businesses: support continued development and maintenance via invoiced sponsorin
 
 Dear ImGui is a **bloat-free graphical user interface library for C++**. It outputs optimized vertex buffers that you can render anytime in your 3D-pipeline-enabled application. It is fast, portable, renderer agnostic, and self-contained (no external dependencies).
 
-Dear ImGui is designed to **enable fast iterations** and to **empower programmers** to create **content creation tools and visualization / debug tools** (as opposed to UI for the average end-user). It favors simplicity and productivity toward this goal and lacks certain features commonly found in more high-level libraries.
+Dear ImGui is designed to **enable fast iterations** and to **empower programmers** to create **content creation tools and visualization / debug tools** (as opposed to UI for the average end-user). It favors simplicity and productivity toward this goal and lacks certain features commonly found in more high-level libraries. Among other things, full internationalization (right-to-left text, bidirectional text, text shaping etc.) and accessibility features are not supported.
 
 Dear ImGui is particularly suited to integration in game engines (for tooling), real-time 3D applications, fullscreen applications, embedded applications, or any applications on console platforms where operating system features are non-standard.
 
@@ -43,7 +43,7 @@ Dear ImGui is particularly suited to integration in game engines (for tooling),
 
 **Backends for a variety of graphics API and rendering platforms** are provided in the [backends/](https://github.com/ocornut/imgui/tree/master/backends) folder, along with example applications in the [examples/](https://github.com/ocornut/imgui/tree/master/examples) folder. You may also create your own backend. Anywhere where you can render textured triangles, you can render Dear ImGui.
 
-See the [Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started) guide and [Integration](#integration) section of this document for more details.
+See the [Getting Started & Integration](#getting-started--integration) section of this document for more details.
 
 After Dear ImGui is set up in your application, you can use it from \_anywhere\_ in your program loop:
 ```cpp
@@ -110,11 +110,11 @@ Reading the changelogs is a good way to keep up to date with the things Dear ImG
 Calling the `ImGui::ShowDemoWindow()` function will create a demo window showcasing a variety of features and examples. The code is always available for reference in `imgui_demo.cpp`. [Here's how the demo looks](https://raw.githubusercontent.com/wiki/ocornut/imgui/web/v167/v167-misc.png).
 
 You should be able to build the examples from sources. If you don't, let us know! If you want to have a quick look at some Dear ImGui features, you can download Windows binaries of the demo app here:
-- [imgui-demo-binaries-20240105.zip](https://www.dearimgui.com/binaries/imgui-demo-binaries-20240105.zip) (Windows, 1.90.1 WIP, built 2024/01/05, master) or [older binaries](https://www.dearimgui.com/binaries).
+- [imgui-demo-binaries-20241211.zip](https://www.dearimgui.com/binaries/imgui-demo-binaries-20241211.zip) (Windows, 1.91.6, built 2024/11/11, master) or [older binaries](https://www.dearimgui.com/binaries).
 
 The demo applications are not DPI aware so expect some blurriness on a 4K screen. For DPI awareness in your application, you can load/reload your font at a different scale and scale your style with `style.ScaleAllSizes()` (see [FAQ](https://www.dearimgui.com/faq)).
 
-### Integration
+### Getting Started & Integration
 
 See the [Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started) guide for details.
 
@@ -141,7 +141,7 @@ Also see [Wiki](https://github.com/ocornut/imgui/wiki) for more links and ideas.
 
 Examples projects using Dear ImGui: [Tracy](https://github.com/wolfpld/tracy) (profiler), [ImHex](https://github.com/WerWolv/ImHex) (hex editor/data analysis), [RemedyBG](https://remedybg.itch.io/remedybg) (debugger) and [hundreds of others](https://github.com/ocornut/imgui/wiki/Software-using-Dear-ImGui).
 
-For more user-submitted screenshots of projects using Dear ImGui, check out the [Gallery Threads](https://github.com/ocornut/imgui/issues/7503)!
+For more user-submitted screenshots of projects using Dear ImGui, check out the [Gallery Threads](https://github.com/ocornut/imgui/issues?q=label%3Agallery)!
 
 For a list of third-party widgets and extensions, check out the [Useful Extensions/Widgets](https://github.com/ocornut/imgui/wiki/Useful-Extensions) wiki page.
 
@@ -170,11 +170,11 @@ Private support is available for paying business customers (E-mail: _contact @ d
 
 **Which version should I get?**
 
-We occasionally tag [Releases](https://github.com/ocornut/imgui/releases) (with nice releases notes) but it is generally safe and recommended to sync to latest `master` or `docking` branch. The library is fairly stable and regressions tend to be fixed fast when reported. Advanced users may want to use the `docking` branch with [Multi-Viewport](https://github.com/ocornut/imgui/issues/1542) and [Docking](https://github.com/ocornut/imgui/issues/2109) features. This branch is kept in sync with master regularly.
+We occasionally tag [Releases](https://github.com/ocornut/imgui/releases) (with nice releases notes) but it is generally safe and recommended to sync to latest `master` or `docking` branch. The library is fairly stable and regressions tend to be fixed fast when reported. Advanced users may want to use the `docking` branch with [Multi-Viewport](https://github.com/ocornut/imgui/wiki/Multi-Viewports) and [Docking](https://github.com/ocornut/imgui/wiki/Docking) features. This branch is kept in sync with master regularly.
 
 **Who uses Dear ImGui?**
 
-See the [Quotes](https://github.com/ocornut/imgui/wiki/Quotes), [Funding & Sponsors](https://github.com/ocornut/imgui/wiki/Funding), and [Software using Dear ImGui](https://github.com/ocornut/imgui/wiki/Software-using-dear-imgui) Wiki pages for an idea of who is using Dear ImGui. Please add your game/software if you can! Also, see the [Gallery Threads](https://github.com/ocornut/imgui/issues/7503)!
+See the [Quotes](https://github.com/ocornut/imgui/wiki/Quotes), [Funding & Sponsors](https://github.com/ocornut/imgui/wiki/Funding), and [Software using Dear ImGui](https://github.com/ocornut/imgui/wiki/Software-using-dear-imgui) Wiki pages for an idea of who is using Dear ImGui. Please add your game/software if you can! Also, see the [Gallery Threads](https://github.com/ocornut/imgui/issues?q=label%3Agallery)!
 
 How to help
 -----------
@@ -196,7 +196,7 @@ Ongoing Dear ImGui development is and has been financially supported by users an
 **THANK YOU to all past and present supporters for helping to keep this project alive and thriving!**
 
 Dear ImGui is using software and services provided free of charge for open source projects:
-- [PVS-Studio](https://www.viva64.com/en/b/0570/) for static analysis.
+- [PVS-Studio](https://pvs-studio.com/en/pvs-studio/?utm_source=website&utm_medium=github&utm_campaign=open_source) for static analysis (supports C/C++/C#/Java).
 - [GitHub actions](https://github.com/features/actions) for continuous integration systems.
 - [OpenCppCoverage](https://github.com/OpenCppCoverage/OpenCppCoverage) for code coverage analysis.
 

docs/TODO.txt

@@ -9,8 +9,7 @@ It's mostly a bunch of personal notes, probably incomplete. Feel free to query i
  - doc: add a proper documentation system (maybe relying on automation? #435)
  - doc: checklist app to verify backends/integration of imgui (test inputs, rendering, callback, etc.).
  - doc/tips: tips of the day: website? applet in imgui_club?
- - doc/wiki: work on the wiki https://github.com/ocornut/imgui/wiki
-
+ 
  - window: preserve/restore relative focus ordering (persistent or not), and e.g. of multiple reappearing windows (#2304) -> also see docking reference to same #.
  - window: calling SetNextWindowSize() every frame with <= 0 doesn't do anything, may be useful to allow (particularly when used for a single axis). (#690)
  - window: add a way for very transient windows (non-saved, temporary overlay over hundreds of objects) to "clean" up from the global window list. perhaps a lightweight explicit cleanup pass.
@@ -44,7 +43,7 @@ It's mostly a bunch of personal notes, probably incomplete. Feel free to query i
  - drawlist: maintaining bounding box per command would allow to merge draw command when clipping isn't relied on (typical non-scrolling window or non-overflowing column would merge with previous command). (WIP branch)
  - drawlist: make it easier to toggle AA per primitive, so we can use e.g. non-AA fill + AA borders more naturally
  - drawlist: non-AA strokes have gaps between points (#593, #288), glitch especially on RenderCheckmark() and ColorPicker4().
- - drawlist: callback: add an extra void* in ImDrawCallback to allow passing render-local data to the callback (would break API).
+ - drawlist: callback: add an extra void* in ImDrawCallback to expose render state instead of pulling from Renderer_RenderState (would break API).
  - drawlist: AddRect vs AddLine position confusing (#2441)
  - drawlist/opt: store rounded corners in texture to use 1 quad per corner (filled and wireframe) to lower the cost of rounding. (#1962)
  - drawlist/opt: AddRect() axis aligned pixel aligned (no-aa) could use 8 triangles instead of 16 and no normal calculation.
@@ -65,7 +64,6 @@ It's mostly a bunch of personal notes, probably incomplete. Feel free to query i
  - selectable: generic BeginSelectable()/EndSelectable() mechanism. (work out alongside range-select branch)
  - selectable: a way to visualize partial/mixed selection (e.g. parent tree node has children with mixed selection)
 
- - input text: clean up the mess caused by converting UTF-8 <> wchar. the code is rather inefficient right now and super fragile. (WIP branch)
  - input text: preserve scrolling when unfocused?
  - input text: reorganize event handling, allow CharFilter to modify buffers, allow multiple events? (#541)
  - input text: expose CursorPos in char filter event (#816)
@@ -129,7 +127,35 @@ It's mostly a bunch of personal notes, probably incomplete. Feel free to query i
  - separator: width, thickness, centering (#1643, #2657)
  - splitter: formalize the splitter idiom into an official api (we want to handle n-way split) (#319)
 
- - docking: merge docking branch (#2109)
+ - docking: B: ordering currently held in tab bar should be implicitly held by windows themselves (also see #2304)
+ - docking: B- tab bar: the order/focus restoring code could be part of TabBar and not DockNode? (#8)
+ - docking: B~ rework code to be able to lazily create tab bar instance in a single place. The _Unsorted tab flag could be replacing a trailing-counter in DockNode?
+ - docking: B~ fully track windows/settings reference in dock nodes. perhaps find a representation that allows facilitate use of dock builder functions.
+ - docking: B~ Unreal style document system (requires low-level controls of dockspace serialization fork/copy/delete). this is mostly working but the DockBuilderXXX api are not exposed/finished.
+ - docking: B: when docking outer, perform size locking on neighbors nodes the same way we do it with splitters, so other nodes are not resized.
+ - docking: B~ central node resizing behavior incorrect.
+ - docking: B: changing title font/style per-window is not supported as dock nodes are created in NewFrame.
+ - docking: B- dock node inside its own viewports creates 1 temporary viewport per window on startup before ditching them (doesn't affect the user nor request platform windows to be created, but unnecessary)
+ - docking: B- resize sibling locking behavior may be less desirable if we merged same-axis sibling in a same node level?
+ - docking: B- single visible node part of a hidden split hierarchy (OnlyNodeWithWindows != NULL) should show a normal title bar (not a tab bar)
+ - docking: B~ SetNextWindowDock() calls (with conditional) -> defer everything to DockContextUpdate (repro: Documents->[X]Windows->Dock 1 elsewhere->Click Redock All
+ - docking: B~ tidy up tab list popup buttons features (available with manual tab-bar, see ImGuiTabBarFlags_NoTabListPopupButton code, not used by docking nodes)
+ - docking: B- SetNextWindowDockId(0) with a second Begin() in the frame will asserts
+ - docking: B: resize grip drawn in host window typically appears under scrollbar.
+ - docking: B: resize grip auto-resize on multiple node hierarchy doesn't make much sense or should be improved?
+ - docking: B- SetNextWindowFocus() doesn't seem to apply if the window is hidden this frame, need repro (#4)
+ - docking: B- resizing a dock tree small currently has glitches (overlapping collapse and close button, etc.)
+ - docking: B- dpi: look at interaction with the hi-dpi and multi-dpi stuff.
+ - docking: B- tab bar: appearing on first frame with a dumb layout would do less harm that not appearing? (when behind dynamic branch) or store titles + render in EndTabBar()
+ - docking: B- tab bar: make selected tab always shows its full title?
+ - docking: B- hide close button on single tab bar?
+ - docking: B- nav: design interactions so nav controls can dock/undock
+ - docking: B- dockspace: flag to lock the dock tree and/or sizes (ImGuiDockNodeFlags_Locked?)
+ - docking: B- reintroduce collapsing a floating dock node. also collapsing a docked dock node!
+ - docking: B- allow dragging a non-floating dock node by clicking on the title-bar-looking section (not just the collapse/menu button)
+ - docking: B- option to remember undocked window size? (instead of keeping their docked size) (relate to #2104)
+ - docking: C- nav: CTRL+TAB highlighting tabs shows the mismatch between focus-stack and tab-order (not visible in VS because it doesn't highlight the tabs)
+ - docking: C- after a dock/undock, the Scrollbar Status update in Begin() should use an updated e.g. size_y_for_scrollbars to avoid a 1 frame scrollbar flicker.
 
  - tabs: "there is currently a problem because TabItem() will try to submit their own tooltip after 0.50 second, and this will have the effect of making your tooltip flicker once." -> tooltip priority work (WIP branch)
  - tabs: make EndTabBar fail if users doesn't respect BeginTabBar return value, for consistency/future-proofing.
@@ -190,11 +216,11 @@ It's mostly a bunch of personal notes, probably incomplete. Feel free to query i
  - tree node/opt: could avoid formatting when clipped (flag assuming we don't care about width/height, assume single line height? format only %s/%c to be able to count height?)
 
  - settings: write more decent code to allow saving/loading new fields: columns, selected tree nodes?
+ - settings: facilitate extension lazily calling AddSettingsHandler() while running and still getting their data call the ReadXXX handlers immediately.
  - settings: api for per-tool simple persistent data (bool,int,float,columns sizes,etc.) in .ini file (#437)
  - settings/persistence: helpers to make TreeNodeBehavior persist (even during dev!) - may need to store some semantic and/or data type in ImGuiStoragePair
 
  - style: better default styles. (#707)
- - style: PushStyleVar: allow direct access to individual float X/Y elements.
  - style: add a highlighted text color (for headers, etc.)
  - style: border types: out-screen, in-screen, etc. (#447)
  - style: add window shadow (fading away from the window. Paint-style calculation of vertices alpha after drawlist would be easier)
@@ -276,14 +302,13 @@ It's mostly a bunch of personal notes, probably incomplete. Feel free to query i
  - font/opt: Glyph currently 40 bytes (2+9*4). Consider storing UV as 16-bits integer? (->32 bytes). X0/Y0/X1/Y1 as 16 fixed-point integers? Or X0/Y0 as float and X1/Y1 as fixed8_8?
 
  - nav: some features such as PageUp/Down/Home/End should probably work without ImGuiConfigFlags_NavEnableKeyboard? (where do we draw the line? how about CTRL+Tab)
- ! nav: never clear NavId on some setup (e.g. gamepad centric)
- - nav: there's currently no way to completely clear focus with the keyboard. depending on patterns used by the application to dispatch inputs, it may be desirable.
  - nav: Home/End behavior when navigable item is not fully visible at the edge of scrolling? should be backtrack to keep item into view?
  - nav: NavScrollToBringItemIntoView() with item bigger than view should focus top-right? Repro: using Nav in "About Window"
- - nav: wrap around logic to allow e.g. grid based layout (pressing NavRight on the right-most element would go to the next row, etc.). see internal's NavMoveRequestTryWrapping().
+ - nav: expose wrap around flags/logic to allow e.g. grid based layout (pressing NavRight on the right-most element would go to the next row, etc.). see internal's NavMoveRequestTryWrapping().
  - nav: patterns to make it possible for arrows key to update selection (see JustMovedTo in range_select branch)
  - nav: restore/find nearest NavId when current one disappear (e.g. pressed a button that disappear, or perhaps auto restoring when current button change name)
  - nav: SetItemDefaultFocus() level of priority, so widget like Selectable when inside a popup could claim a low-priority default focus on the first selected iem
+ - nav: holding space to repeat a button doesn't show button activated during hold.
  - nav: NavFlattened: init requests don't work properly on flattened siblings.
  - nav: NavFlattened: pageup/pagedown/home/end don't work properly on flattened siblings.
  - nav: NavFlattened: ESC on a flattened child should select something.
@@ -302,6 +327,20 @@ It's mostly a bunch of personal notes, probably incomplete. Feel free to query i
  - nav/windowing: Resizing window will currently fail with certain types of resizing constraints/callback applied
  - focus: preserve ActiveId/focus stack state, e.g. when opening a menu and close it, previously selected InputText() focus gets restored (#622)
 
+ - viewport: make it possible to have no main/hosting viewport
+ - viewport: We set ImGuiViewportFlags_NoFocusOnAppearing in a way that is required for GLFW/SDL binding, but could be handled better without
+   on a custom e.g. Win32 bindings. It prevents newly dragged-out viewports from taking the focus, which makes ALT+F4 more ambiguous.
+ - viewport: not focusing newly undocked viewport means clicking back on previous one doesn't bring OS window to front.
+ - viewport: with platform decoration enabled, platform may force constraint (e.g. minimum size)
+ - viewport: use getfocus/setfocus api to synchronize imgui<>platform focus better (e.g imgui-side ctrl-tab can focus os window, OS initial setup and alt-tab can focus imgui window etc.)
+ - viewport: store per-viewport/monitor DPI in .ini file so an application reload or main window changing DPI on reload can be properly patched for.
+ - viewport: implicit/fallback Debug window can hog a zombie viewport (harmless, noisy?) > could at least clear out the reference on a per session basis?
+ - viewport: need to clarify how to use GetMousePos() from a user point of view.
+ - platform: glfw: no support for ImGuiBackendFlags_HasMouseHoveredViewport.
+ - platform: sdl: no support for ImGuiBackendFlags_HasMouseHoveredViewport. maybe we could use SDL_GetMouseFocus() / SDL_WINDOW_MOUSE_FOCUS if imgui could fallback on its heuristic when NoInputs is set
+ - platform: sdl: no refresh of monitor/display (SDL doesn't seem to have an event for it).
+ - platform: sdl: multi-viewport + minimized window seems to break mouse wheel events (at least under Win32).
+
  - inputs: support track pad style scrolling & slider edit.
  - inputs/io: backspace and arrows in the context of a text input could use system repeat rate.
  - inputs/io: clarify/standardize/expose repeat rate and repeat delays (#1808)

examples/example_allegro5/main.cpp

@@ -40,6 +40,7 @@ int main(int, char**)
     ImGui::CreateContext();
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;  // Enable Keyboard Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;      // Enable Docking
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();

examples/example_android_opengl3/android/app/src/main/AndroidManifest.xml

@@ -11,7 +11,7 @@
             android:name="imgui.example.android.MainActivity"
             android:theme="@android:style/Theme.NoTitleBar.Fullscreen"
             android:configChanges="orientation|keyboardHidden|screenSize"
-            android:exported="false">
+            android:exported="true">
             <meta-data android:name="android.app.lib_name"
                 android:value="ImGuiExample" />
 

examples/example_android_opengl3/main.cpp

@@ -68,7 +68,7 @@ void android_main(struct android_app* app)
         struct android_poll_source* out_data;
 
         // Poll all events. If the app is not visible, this loop blocks until g_Initialized == true.
-        while (ALooper_pollAll(g_Initialized ? 0 : -1, nullptr, &out_events, (void**)&out_data) >= 0)
+        while (ALooper_pollOnce(g_Initialized ? 0 : -1, nullptr, &out_events, (void**)&out_data) >= 0)
         {
             // Process one event
             if (out_data != nullptr)

examples/example_apple_metal/example_apple_metal.xcodeproj/project.pbxproj

@@ -7,7 +7,10 @@
 	objects = {
 
 /* Begin PBXBuildFile section */
+		050450AB2768052600AB6805 /* imgui_tables.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 5079822D257677DB0038A28D /* imgui_tables.cpp */; };
+		050450AD276863B000AB6805 /* QuartzCore.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 050450AC276863B000AB6805 /* QuartzCore.framework */; };
 		05318E0F274C397200A8DE2E /* GameController.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 05318E0E274C397200A8DE2E /* GameController.framework */; };
+		05A275442773BEA20084EF39 /* QuartzCore.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 05A275432773BEA20084EF39 /* QuartzCore.framework */; };
 		07A82ED82139413D0078D120 /* imgui_widgets.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 07A82ED72139413C0078D120 /* imgui_widgets.cpp */; };
 		07A82ED92139418F0078D120 /* imgui_widgets.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 07A82ED72139413C0078D120 /* imgui_widgets.cpp */; };
 		5079822E257677DB0038A28D /* imgui_tables.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 5079822D257677DB0038A28D /* imgui_tables.cpp */; };
@@ -33,7 +36,11 @@
 /* End PBXBuildFile section */
 
 /* Begin PBXFileReference section */
+		050450AC276863B000AB6805 /* QuartzCore.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = QuartzCore.framework; path = System/Library/Frameworks/QuartzCore.framework; sourceTree = SDKROOT; };
 		05318E0E274C397200A8DE2E /* GameController.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = GameController.framework; path = System/Library/Frameworks/GameController.framework; sourceTree = SDKROOT; };
+		05A2754027728F5B0084EF39 /* imgui_impl_metal.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = imgui_impl_metal.h; path = ../../backends/imgui_impl_metal.h; sourceTree = "<group>"; };
+		05A2754127728F5B0084EF39 /* imgui_impl_osx.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = imgui_impl_osx.h; path = ../../backends/imgui_impl_osx.h; sourceTree = "<group>"; };
+		05A275432773BEA20084EF39 /* QuartzCore.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = QuartzCore.framework; path = Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS15.2.sdk/System/Library/Frameworks/QuartzCore.framework; sourceTree = DEVELOPER_DIR; };
 		07A82ED62139413C0078D120 /* imgui_internal.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = imgui_internal.h; path = ../../imgui_internal.h; sourceTree = "<group>"; };
 		07A82ED72139413C0078D120 /* imgui_widgets.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = imgui_widgets.cpp; path = ../../imgui_widgets.cpp; sourceTree = "<group>"; };
 		5079822D257677DB0038A28D /* imgui_tables.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = imgui_tables.cpp; path = ../../imgui_tables.cpp; sourceTree = "<group>"; };
@@ -66,6 +73,7 @@
 			isa = PBXFrameworksBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				05A275442773BEA20084EF39 /* QuartzCore.framework in Frameworks */,
 				8309BD8F253CCAAA0045E2A1 /* UIKit.framework in Frameworks */,
 				83BBE9E720EB46BD00295997 /* MetalKit.framework in Frameworks */,
 				83BBE9E520EB46B900295997 /* Metal.framework in Frameworks */,
@@ -76,6 +84,7 @@
 			isa = PBXFrameworksBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				050450AD276863B000AB6805 /* QuartzCore.framework in Frameworks */,
 				8309BDC6253CCCFE0045E2A1 /* AppKit.framework in Frameworks */,
 				83BBE9EC20EB471700295997 /* MetalKit.framework in Frameworks */,
 				05318E0F274C397200A8DE2E /* GameController.framework in Frameworks */,
@@ -136,6 +145,8 @@
 		83BBE9E320EB46B800295997 /* Frameworks */ = {
 			isa = PBXGroup;
 			children = (
+				050450AC276863B000AB6805 /* QuartzCore.framework */,
+				05A275432773BEA20084EF39 /* QuartzCore.framework */,
 				05318E0E274C397200A8DE2E /* GameController.framework */,
 				8309BDC5253CCCFE0045E2A1 /* AppKit.framework */,
 				8309BD8E253CCAAA0045E2A1 /* UIKit.framework */,
@@ -153,7 +164,9 @@
 			isa = PBXGroup;
 			children = (
 				5079822D257677DB0038A28D /* imgui_tables.cpp */,
+				05A2754027728F5B0084EF39 /* imgui_impl_metal.h */,
 				8309BDB5253CCC9D0045E2A1 /* imgui_impl_metal.mm */,
+				05A2754127728F5B0084EF39 /* imgui_impl_osx.h */,
 				8309BDB6253CCC9D0045E2A1 /* imgui_impl_osx.mm */,
 				83BBEA0420EB54E700295997 /* imconfig.h */,
 				83BBEA0320EB54E700295997 /* imgui.cpp */,
@@ -268,9 +281,9 @@
 				8309BDBB253CCCAD0045E2A1 /* imgui_impl_metal.mm in Sources */,
 				83BBEA0920EB54E700295997 /* imgui.cpp in Sources */,
 				83BBEA0720EB54E700295997 /* imgui_demo.cpp in Sources */,
-                83BBEA0520EB54E700295997 /* imgui_draw.cpp in Sources */,
+				83BBEA0520EB54E700295997 /* imgui_draw.cpp in Sources */,
 				5079822E257677DB0038A28D /* imgui_tables.cpp in Sources */,
-                07A82ED82139413D0078D120 /* imgui_widgets.cpp in Sources */,
+				07A82ED82139413D0078D120 /* imgui_widgets.cpp in Sources */,
 				8309BDA5253CCC070045E2A1 /* main.mm in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
@@ -281,10 +294,10 @@
 			files = (
 				8309BDBE253CCCB60045E2A1 /* imgui_impl_metal.mm in Sources */,
 				8309BDBF253CCCB60045E2A1 /* imgui_impl_osx.mm in Sources */,
-                83BBEA0A20EB54E700295997 /* imgui.cpp in Sources */,
-                83BBEA0820EB54E700295997 /* imgui_demo.cpp in Sources */,
-                83BBEA0620EB54E700295997 /* imgui_draw.cpp in Sources */,
-                5079822E257677DB0038A28D /* imgui_tables.cpp in Sources */,
+				83BBEA0A20EB54E700295997 /* imgui.cpp in Sources */,
+				83BBEA0820EB54E700295997 /* imgui_demo.cpp in Sources */,
+				83BBEA0620EB54E700295997 /* imgui_draw.cpp in Sources */,
+				050450AB2768052600AB6805 /* imgui_tables.cpp in Sources */,
 				07A82ED92139418F0078D120 /* imgui_widgets.cpp in Sources */,
 				8309BDA8253CCC080045E2A1 /* main.mm in Sources */,
 			);

examples/example_apple_metal/main.mm

@@ -60,11 +60,21 @@
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
+    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;       // Enable Multi-Viewport / Platform Windows
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsLight();
 
+    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
+    ImGuiStyle& style = ImGui::GetStyle();
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        style.WindowRounding = 0.0f;
+        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
+    }
+
     // Setup Renderer backend
     ImGui_ImplMetal_Init(_device);
 
@@ -195,6 +205,13 @@
 	// Present
     [commandBuffer presentDrawable:view.currentDrawable];
     [commandBuffer commit];
+
+    // Update and Render additional Platform Windows
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        ImGui::UpdatePlatformWindows();
+        ImGui::RenderPlatformWindowsDefault();
+    }
 }
 
 -(void)mtkView:(MTKView*)view drawableSizeWillChange:(CGSize)size

examples/example_apple_opengl2/main.mm

@@ -47,11 +47,21 @@
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
+    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;       // Enable Multi-Viewport / Platform Windows
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsLight();
 
+    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
+    ImGuiStyle& style = ImGui::GetStyle();
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        style.WindowRounding = 0.0f;
+        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
+    }
+
     // Setup Platform/Renderer backends
     ImGui_ImplOSX_Init(self);
     ImGui_ImplOpenGL2_Init();
@@ -136,6 +146,13 @@
 
     ImGui_ImplOpenGL2_RenderDrawData(draw_data);
 
+    // Update and Render additional Platform Windows
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        ImGui::UpdatePlatformWindows();
+        ImGui::RenderPlatformWindowsDefault();
+    }
+
     // Present
     [[self openGLContext] flushBuffer];
 

examples/example_glfw_metal/main.mm

@@ -33,11 +33,21 @@ int main(int, char**)
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;  // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;   // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;      // Enable Docking
+    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;    // Enable Multi-Viewport / Platform Windows
 
     // Setup style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsLight();
 
+    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
+    ImGuiStyle& style = ImGui::GetStyle();
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        style.WindowRounding = 0.0f;
+        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
+    }
+
     // Load Fonts
     // - If no fonts are loaded, dear imgui will use the default font. You can also load multiple fonts and use ImGui::PushFont()/PopFont() to select them.
     // - AddFontFromFileTTF() will return the ImFont* so you can store it if you need to select the font among multiple.
@@ -69,7 +79,7 @@ int main(int, char**)
     id <MTLCommandQueue> commandQueue = [device newCommandQueue];
 
     // Setup Platform/Renderer backends
-    ImGui_ImplGlfw_InitForOpenGL(window, true);
+    ImGui_ImplGlfw_InitForOther(window, true);
     ImGui_ImplMetal_Init(device);
 
     NSWindow *nswin = glfwGetCocoaWindow(window);
@@ -157,6 +167,13 @@ int main(int, char**)
             ImGui::Render();
             ImGui_ImplMetal_RenderDrawData(ImGui::GetDrawData(), commandBuffer, renderEncoder);
 
+            // Update and Render additional Platform Windows
+            if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+            {
+                ImGui::UpdatePlatformWindows();
+                ImGui::RenderPlatformWindowsDefault();
+            }
+
             [renderEncoder popDebugGroup];
             [renderEncoder endEncoding];
 

examples/example_glfw_opengl2/main.cpp

@@ -52,11 +52,23 @@ int main(int, char**)
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
+    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;       // Enable Multi-Viewport / Platform Windows
+    //io.ConfigViewportsNoAutoMerge = true;
+    //io.ConfigViewportsNoTaskBarIcon = true;
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsLight();
 
+    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
+    ImGuiStyle& style = ImGui::GetStyle();
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        style.WindowRounding = 0.0f;
+        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
+    }
+
     // Setup Platform/Renderer backends
     ImGui_ImplGlfw_InitForOpenGL(window, true);
     ImGui_ImplOpenGL2_Init();
@@ -91,6 +103,11 @@ int main(int, char**)
         // - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application, or clear/overwrite your copy of the keyboard data.
         // Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
         glfwPollEvents();
+        if (glfwGetWindowAttrib(window, GLFW_ICONIFIED) != 0)
+        {
+            ImGui_ImplGlfw_Sleep(10);
+            continue;
+        }
 
         // Start the Dear ImGui frame
         ImGui_ImplOpenGL2_NewFrame();
@@ -150,6 +167,17 @@ int main(int, char**)
         ImGui_ImplOpenGL2_RenderDrawData(ImGui::GetDrawData());
         //glUseProgram(last_program);
 
+        // Update and Render additional Platform Windows
+        // (Platform functions may change the current OpenGL context, so we save/restore it to make it easier to paste this code elsewhere.
+        //  For this specific demo app we could also call glfwMakeContextCurrent(window) directly)
+        if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+        {
+            GLFWwindow* backup_current_context = glfwGetCurrentContext();
+            ImGui::UpdatePlatformWindows();
+            ImGui::RenderPlatformWindowsDefault();
+            glfwMakeContextCurrent(backup_current_context);
+        }
+
         glfwMakeContextCurrent(window);
         glfwSwapBuffers(window);
     }

examples/example_glfw_opengl3/Makefile.emscripten

@@ -35,6 +35,9 @@ EMS =
 EMS += -s DISABLE_EXCEPTION_CATCHING=1
 LDFLAGS += -s USE_GLFW=3 -s WASM=1 -s ALLOW_MEMORY_GROWTH=1 -s NO_EXIT_RUNTIME=0 -s ASSERTIONS=1
 
+# Build as single file (binary text encoded in .html file)
+#LDFLAGS += -sSINGLE_FILE
+
 # Uncomment next line to fix possible rendering bugs with Emscripten version older then 1.39.0 (https://github.com/ocornut/imgui/issues/2877)
 #EMS += -s BINARYEN_TRAP_MODE=clamp
 #EMS += -s SAFE_HEAP=1    ## Adds overhead

examples/example_glfw_opengl3/main.cpp

@@ -43,11 +43,17 @@ int main(int, char**)
 
     // Decide GL+GLSL versions
 #if defined(IMGUI_IMPL_OPENGL_ES2)
-    // GL ES 2.0 + GLSL 100
+    // GL ES 2.0 + GLSL 100 (WebGL 1.0)
     const char* glsl_version = "#version 100";
     glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 2);
     glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);
     glfwWindowHint(GLFW_CLIENT_API, GLFW_OPENGL_ES_API);
+#elif defined(IMGUI_IMPL_OPENGL_ES3)
+    // GL ES 3.0 + GLSL 300 es (WebGL 2.0)
+    const char* glsl_version = "#version 300 es";
+    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
+    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);
+    glfwWindowHint(GLFW_CLIENT_API, GLFW_OPENGL_ES_API);
 #elif defined(__APPLE__)
     // GL 3.2 + GLSL 150
     const char* glsl_version = "#version 150";
@@ -77,15 +83,27 @@ int main(int, char**)
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
+    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;       // Enable Multi-Viewport / Platform Windows
+    //io.ConfigViewportsNoAutoMerge = true;
+    //io.ConfigViewportsNoTaskBarIcon = true;
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsLight();
 
+    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
+    ImGuiStyle& style = ImGui::GetStyle();
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        style.WindowRounding = 0.0f;
+        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
+    }
+
     // Setup Platform/Renderer backends
     ImGui_ImplGlfw_InitForOpenGL(window, true);
 #ifdef __EMSCRIPTEN__
-    ImGui_ImplGlfw_InstallEmscriptenCanvasResizeCallback("#canvas");
+    ImGui_ImplGlfw_InstallEmscriptenCallbacks(window, "#canvas");
 #endif
     ImGui_ImplOpenGL3_Init(glsl_version);
 
@@ -127,6 +145,11 @@ int main(int, char**)
         // - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application, or clear/overwrite your copy of the keyboard data.
         // Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
         glfwPollEvents();
+        if (glfwGetWindowAttrib(window, GLFW_ICONIFIED) != 0)
+        {
+            ImGui_ImplGlfw_Sleep(10);
+            continue;
+        }
 
         // Start the Dear ImGui frame
         ImGui_ImplOpenGL3_NewFrame();
@@ -179,6 +202,17 @@ int main(int, char**)
         glClear(GL_COLOR_BUFFER_BIT);
         ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
 
+        // Update and Render additional Platform Windows
+        // (Platform functions may change the current OpenGL context, so we save/restore it to make it easier to paste this code elsewhere.
+        //  For this specific demo app we could also call glfwMakeContextCurrent(window) directly)
+        if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+        {
+            GLFWwindow* backup_current_context = glfwGetCurrentContext();
+            ImGui::UpdatePlatformWindows();
+            ImGui::RenderPlatformWindowsDefault();
+            glfwMakeContextCurrent(backup_current_context);
+        }
+
         glfwSwapBuffers(window);
     }
 #ifdef __EMSCRIPTEN__

examples/example_glfw_vulkan/CMakeLists.txt

@@ -42,4 +42,4 @@ file(GLOB sources *.cpp)
 
 add_executable(example_glfw_vulkan ${sources} ${IMGUI_DIR}/backends/imgui_impl_glfw.cpp ${IMGUI_DIR}/backends/imgui_impl_vulkan.cpp ${IMGUI_DIR}/imgui.cpp ${IMGUI_DIR}/imgui_draw.cpp ${IMGUI_DIR}/imgui_demo.cpp ${IMGUI_DIR}/imgui_tables.cpp ${IMGUI_DIR}/imgui_widgets.cpp)
 target_link_libraries(example_glfw_vulkan ${LIBRARIES})
-target_compile_definitions(example_glfw_vulkan PUBLIC -DImTextureID=ImU64)
+

examples/example_glfw_vulkan/build_win32.bat

@@ -7,8 +7,8 @@
 
 @set OUT_DIR=Debug
 mkdir %OUT_DIR%
-cl /nologo /Zi /MD /utf-8 %INCLUDES% /D ImTextureID=ImU64 %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS%
+cl /nologo /Zi /MD /utf-8 %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS%
 
 @set OUT_DIR=Release
 mkdir %OUT_DIR%
-cl /nologo /Zi /MD /utf-8 /Ox /Oi %INCLUDES% /D ImTextureID=ImU64 %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS%
+cl /nologo /Zi /MD /utf-8 /Ox /Oi %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS%

examples/example_glfw_vulkan/build_win64.bat

@@ -1,13 +1,14 @@
-@REM Build for Visual Studio compiler. Run your copy of amd64/vcvars32.bat to setup 64-bit command-line compiler.
+@REM Build for Visual Studio compiler. Run your copy of vcvars64.bat or vcvarsall.bat to setup 64-bit command-line compiler.
 
+@set OUT_EXE=example_glfw_vulkan
 @set INCLUDES=/I..\.. /I..\..\backends /I..\libs\glfw\include /I %VULKAN_SDK%\include
 @set SOURCES=main.cpp ..\..\backends\imgui_impl_vulkan.cpp ..\..\backends\imgui_impl_glfw.cpp ..\..\imgui*.cpp
 @set LIBS=/LIBPATH:..\libs\glfw\lib-vc2010-64 /libpath:%VULKAN_SDK%\lib glfw3.lib opengl32.lib gdi32.lib shell32.lib vulkan-1.lib
 
 @set OUT_DIR=Debug
 mkdir %OUT_DIR%
-cl /nologo /Zi /MD /utf-8 %INCLUDES% /D ImTextureID=ImU64 %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS%
+cl /nologo /Zi /MD /utf-8 %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS%
 
 @set OUT_DIR=Release
 mkdir %OUT_DIR%
-cl /nologo /Zi /MD /utf-8 /Ox /Oi %INCLUDES% /D ImTextureID=ImU64 %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS%
+cl /nologo /Zi /MD /utf-8 /Ox /Oi %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS%

examples/example_glfw_vulkan/example_glfw_vulkan.vcxproj

@@ -91,7 +91,7 @@
       <WarningLevel>Level4</WarningLevel>
       <Optimization>Disabled</Optimization>
       <AdditionalIncludeDirectories>..\..;..\..\backends;%VULKAN_SDK%\include;..\libs\glfw\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>ImTextureID=ImU64;_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
     </ClCompile>
     <Link>
@@ -107,7 +107,7 @@
       <WarningLevel>Level4</WarningLevel>
       <Optimization>Disabled</Optimization>
       <AdditionalIncludeDirectories>..\..;..\..\backends;%VULKAN_SDK%\include;..\libs\glfw\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>ImTextureID=ImU64;_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
     </ClCompile>
     <Link>
@@ -126,7 +126,7 @@
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <AdditionalIncludeDirectories>..\..;..\..\backends;%VULKAN_SDK%\include;..\libs\glfw\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <BufferSecurityCheck>false</BufferSecurityCheck>
-      <PreprocessorDefinitions>ImTextureID=ImU64;_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
     </ClCompile>
     <Link>
@@ -148,7 +148,7 @@
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <AdditionalIncludeDirectories>..\..;..\..\backends;%VULKAN_SDK%\include;..\libs\glfw\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <BufferSecurityCheck>false</BufferSecurityCheck>
-      <PreprocessorDefinitions>ImTextureID=ImU64;_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
     </ClCompile>
     <Link>

examples/example_glfw_vulkan/main.cpp

@@ -25,7 +25,7 @@
 // Volk headers
 #ifdef IMGUI_IMPL_VULKAN_USE_VOLK
 #define VOLK_IMPLEMENTATION
-#include <Volk/volk.h>
+#include <volk.h>
 #endif
 
 // [Win32] Our example includes a copy of glfw3.lib pre-compiled with VS2010 to maximize ease of testing and compatibility with old VS compilers.
@@ -429,11 +429,23 @@ int main(int, char**)
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
+    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;       // Enable Multi-Viewport / Platform Windows
+    //io.ConfigViewportsNoAutoMerge = true;
+    //io.ConfigViewportsNoTaskBarIcon = true;
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsLight();
 
+    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
+    ImGuiStyle& style = ImGui::GetStyle();
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        style.WindowRounding = 0.0f;
+        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
+    }
+
     // Setup Platform/Renderer backends
     ImGui_ImplGlfw_InitForVulkan(window, true);
     ImGui_ImplVulkan_InitInfo init_info = {};
@@ -485,17 +497,19 @@ int main(int, char**)
         glfwPollEvents();
 
         // Resize swap chain?
-        if (g_SwapChainRebuild)
+        int fb_width, fb_height;
+        glfwGetFramebufferSize(window, &fb_width, &fb_height);
+        if (fb_width > 0 && fb_height > 0 && (g_SwapChainRebuild || g_MainWindowData.Width != fb_width || g_MainWindowData.Height != fb_height))
         {
-            int width, height;
-            glfwGetFramebufferSize(window, &width, &height);
-            if (width > 0 && height > 0)
-            {
-                ImGui_ImplVulkan_SetMinImageCount(g_MinImageCount);
-                ImGui_ImplVulkanH_CreateOrResizeWindow(g_Instance, g_PhysicalDevice, g_Device, &g_MainWindowData, g_QueueFamily, g_Allocator, width, height, g_MinImageCount);
-                g_MainWindowData.FrameIndex = 0;
-                g_SwapChainRebuild = false;
-            }
+            ImGui_ImplVulkan_SetMinImageCount(g_MinImageCount);
+            ImGui_ImplVulkanH_CreateOrResizeWindow(g_Instance, g_PhysicalDevice, g_Device, &g_MainWindowData, g_QueueFamily, g_Allocator, fb_width, fb_height, g_MinImageCount);
+            g_MainWindowData.FrameIndex = 0;
+            g_SwapChainRebuild = false;
+        }
+        if (glfwGetWindowAttrib(window, GLFW_ICONIFIED) != 0)
+        {
+            ImGui_ImplGlfw_Sleep(10);
+            continue;
         }
 
         // Start the Dear ImGui frame
@@ -542,17 +556,25 @@ int main(int, char**)
 
         // Rendering
         ImGui::Render();
-        ImDrawData* draw_data = ImGui::GetDrawData();
-        const bool is_minimized = (draw_data->DisplaySize.x <= 0.0f || draw_data->DisplaySize.y <= 0.0f);
-        if (!is_minimized)
+        ImDrawData* main_draw_data = ImGui::GetDrawData();
+        const bool main_is_minimized = (main_draw_data->DisplaySize.x <= 0.0f || main_draw_data->DisplaySize.y <= 0.0f);
+        wd->ClearValue.color.float32[0] = clear_color.x * clear_color.w;
+        wd->ClearValue.color.float32[1] = clear_color.y * clear_color.w;
+        wd->ClearValue.color.float32[2] = clear_color.z * clear_color.w;
+        wd->ClearValue.color.float32[3] = clear_color.w;
+        if (!main_is_minimized)
+            FrameRender(wd, main_draw_data);
+
+        // Update and Render additional Platform Windows
+        if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
         {
-            wd->ClearValue.color.float32[0] = clear_color.x * clear_color.w;
-            wd->ClearValue.color.float32[1] = clear_color.y * clear_color.w;
-            wd->ClearValue.color.float32[2] = clear_color.z * clear_color.w;
-            wd->ClearValue.color.float32[3] = clear_color.w;
-            FrameRender(wd, draw_data);
-            FramePresent(wd);
+            ImGui::UpdatePlatformWindows();
+            ImGui::RenderPlatformWindowsDefault();
         }
+
+        // Present Main Platform Window
+        if (!main_is_minimized)
+            FramePresent(wd);
     }
 
     // Cleanup

examples/example_glfw_wgpu/CMakeLists.txt

@@ -27,6 +27,12 @@ set(IMGUI_DIR ../../)
 
 # Libraries
 if(EMSCRIPTEN)
+  if(EMSCRIPTEN_VERSION VERSION_GREATER_EQUAL "3.1.57")
+    set(IMGUI_EMSCRIPTEN_GLFW3 "--use-port=contrib.glfw3" CACHE STRING "Choose between --use-port=contrib.glfw3 and -sUSE_GLFW=3 for GLFW implementation (default to --use-port=contrib.glfw3)")
+  else()
+    # cannot use contrib.glfw3 prior to 3.1.57
+    set(IMGUI_EMSCRIPTEN_GLFW3 "-sUSE_GLFW=3" CACHE STRING "Use -sUSE_GLFW=3 for GLFW implementation" FORCE)
+  endif()
   set(LIBRARIES glfw)
   add_compile_options(-sDISABLE_EXCEPTION_CATCHING=1 -DIMGUI_DISABLE_FILE_FUNCTIONS=1)
 else()
@@ -73,6 +79,11 @@ add_executable(example_glfw_wgpu
   ${IMGUI_DIR}/imgui_tables.cpp
   ${IMGUI_DIR}/imgui_widgets.cpp
 )
+IF(NOT EMSCRIPTEN)
+  target_compile_definitions(example_glfw_wgpu PUBLIC
+    "IMGUI_IMPL_WEBGPU_BACKEND_DAWN"
+  )
+endif()
 target_include_directories(example_glfw_wgpu PUBLIC
   ${IMGUI_DIR}
   ${IMGUI_DIR}/backends
@@ -82,9 +93,15 @@ target_link_libraries(example_glfw_wgpu PUBLIC ${LIBRARIES})
 
 # Emscripten settings
 if(EMSCRIPTEN)
+  if("${IMGUI_EMSCRIPTEN_GLFW3}" STREQUAL "--use-port=contrib.glfw3")
+    target_compile_options(example_glfw_wgpu PUBLIC
+        "${IMGUI_EMSCRIPTEN_GLFW3}"
+    )
+  endif()
+  message(STATUS "Using ${IMGUI_EMSCRIPTEN_GLFW3} GLFW implementation")
   target_link_options(example_glfw_wgpu PRIVATE
     "-sUSE_WEBGPU=1"
-    "-sUSE_GLFW=3"
+    "${IMGUI_EMSCRIPTEN_GLFW3}"
     "-sWASM=1"
     "-sALLOW_MEMORY_GROWTH=1"
     "-sNO_EXIT_RUNTIME=0"

examples/example_glfw_wgpu/Makefile.emscripten

@@ -36,6 +36,9 @@ EMS += -s DISABLE_EXCEPTION_CATCHING=1
 LDFLAGS += -s USE_GLFW=3 -s USE_WEBGPU=1
 LDFLAGS += -s WASM=1 -s ALLOW_MEMORY_GROWTH=1 -s NO_EXIT_RUNTIME=0 -s ASSERTIONS=1
 
+# Build as single file (binary text encoded in .html file)
+#LDFLAGS += -sSINGLE_FILE
+
 # Emscripten allows preloading a file or folder to be accessible at runtime.
 # The Makefile for this example project suggests embedding the misc/fonts/ folder into our application, it will then be accessible as "/fonts"
 # See documentation for more details: https://emscripten.org/docs/porting/files/packaging_files.html

examples/example_glfw_wgpu/main.cpp

@@ -93,6 +93,7 @@ int main(int, char**)
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
@@ -101,7 +102,7 @@ int main(int, char**)
     // Setup Platform/Renderer backends
     ImGui_ImplGlfw_InitForOther(window, true);
 #ifdef __EMSCRIPTEN__
-    ImGui_ImplGlfw_InstallEmscriptenCanvasResizeCallback("#canvas");
+    ImGui_ImplGlfw_InstallEmscriptenCallbacks(window, "#canvas");
 #endif
     ImGui_ImplWGPU_InitInfo init_info;
     init_info.Device = wgpu_device;
@@ -151,6 +152,11 @@ int main(int, char**)
         // - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application, or clear/overwrite your copy of the keyboard data.
         // Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
         glfwPollEvents();
+        if (glfwGetWindowAttrib(window, GLFW_ICONIFIED) != 0)
+        {
+            ImGui_ImplGlfw_Sleep(10);
+            continue;
+        }
 
         // React to changes in screen size
         int width, height;

examples/example_glut_opengl2/main.cpp

@@ -61,6 +61,7 @@ int main(int argc, char** argv)
     ImGui::CreateContext();
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
@@ -78,7 +79,6 @@ int main(int argc, char** argv)
     // Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
     ImGui_ImplGLUT_InstallFuncs();
 
-
     // Load Fonts
     // - If no fonts are loaded, dear imgui will use the default font. You can also load multiple fonts and use ImGui::PushFont()/PopFont() to select them.
     // - AddFontFromFileTTF() will return the ImFont* so you can store it if you need to select the font among multiple.

examples/example_null/Makefile

@@ -1,6 +1,6 @@
 #
 # Cross Platform Makefile
-# Compatible with MSYS2/MINGW, Ubuntu 14.04.1 and Mac OS X
+# Compatible with MSYS2/MINGW, Ubuntu 14.04.1+ and Mac OS X
 #
 # Important: This is a "null backend" application, with no visible output or interaction!
 # This is used for testing purpose and continuous integration, and has little use for end-user.

examples/example_sdl2_directx11/main.cpp

@@ -71,11 +71,23 @@ int main(int, char**)
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
+    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;       // Enable Multi-Viewport / Platform Windows
+    //io.ConfigViewportsNoAutoMerge = true;
+    //io.ConfigViewportsNoTaskBarIcon = true;
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsLight();
 
+    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
+    ImGuiStyle& style = ImGui::GetStyle();
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        style.WindowRounding = 0.0f;
+        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
+    }
+
     // Setup Platform/Renderer backends
     ImGui_ImplSDL2_InitForD3D(window);
     ImGui_ImplDX11_Init(g_pd3dDevice, g_pd3dDeviceContext);
@@ -126,6 +138,11 @@ int main(int, char**)
                 CreateRenderTarget();
             }
         }
+        if (SDL_GetWindowFlags(window) & SDL_WINDOW_MINIMIZED)
+        {
+            SDL_Delay(10);
+            continue;
+        }
 
         // Start the Dear ImGui frame
         ImGui_ImplDX11_NewFrame();
@@ -176,6 +193,13 @@ int main(int, char**)
         g_pd3dDeviceContext->ClearRenderTargetView(g_mainRenderTargetView, clear_color_with_alpha);
         ImGui_ImplDX11_RenderDrawData(ImGui::GetDrawData());
 
+        // Update and Render additional Platform Windows
+        if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+        {
+            ImGui::UpdatePlatformWindows();
+            ImGui::RenderPlatformWindowsDefault();
+        }
+
         g_pSwapChain->Present(1, 0); // Present with vsync
         //g_pSwapChain->Present(0, 0); // Present without vsync
     }

examples/example_sdl2_metal/main.mm

@@ -24,11 +24,21 @@ int main(int, char**)
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;  // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;   // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;      // Enable Docking
+    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;    // Enable Multi-Viewport / Platform Windows
 
     // Setup style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsLight();
 
+    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
+    ImGuiStyle& style = ImGui::GetStyle();
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        style.WindowRounding = 0.0f;
+        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
+    }
+
     // Load Fonts
     // - If no fonts are loaded, dear imgui will use the default font. You can also load multiple fonts and use ImGui::PushFont()/PopFont() to select them.
     // - AddFontFromFileTTF() will return the ImFont* so you can store it if you need to select the font among multiple.
@@ -168,6 +178,13 @@ int main(int, char**)
             ImGui::Render();
             ImGui_ImplMetal_RenderDrawData(ImGui::GetDrawData(), commandBuffer, renderEncoder);
 
+            // Update and Render additional Platform Windows
+            if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+            {
+                ImGui::UpdatePlatformWindows();
+                ImGui::RenderPlatformWindowsDefault();
+            }
+
             [renderEncoder popDebugGroup];
             [renderEncoder endEncoding];
 

examples/example_sdl2_opengl2/main.cpp

@@ -57,11 +57,23 @@ int main(int, char**)
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
+    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;       // Enable Multi-Viewport / Platform Windows
+    //io.ConfigViewportsNoAutoMerge = true;
+    //io.ConfigViewportsNoTaskBarIcon = true;
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsLight();
 
+    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
+    ImGuiStyle& style = ImGui::GetStyle();
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        style.WindowRounding = 0.0f;
+        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
+    }
+
     // Setup Platform/Renderer backends
     ImGui_ImplSDL2_InitForOpenGL(window, gl_context);
     ImGui_ImplOpenGL2_Init();
@@ -105,6 +117,11 @@ int main(int, char**)
             if (event.type == SDL_WINDOWEVENT && event.window.event == SDL_WINDOWEVENT_CLOSE && event.window.windowID == SDL_GetWindowID(window))
                 done = true;
         }
+        if (SDL_GetWindowFlags(window) & SDL_WINDOW_MINIMIZED)
+        {
+            SDL_Delay(10);
+            continue;
+        }
 
         // Start the Dear ImGui frame
         ImGui_ImplOpenGL2_NewFrame();
@@ -155,6 +172,19 @@ int main(int, char**)
         glClear(GL_COLOR_BUFFER_BIT);
         //glUseProgram(0); // You may want this if using this code in an OpenGL 3+ context where shaders may be bound
         ImGui_ImplOpenGL2_RenderDrawData(ImGui::GetDrawData());
+
+        // Update and Render additional Platform Windows
+        // (Platform functions may change the current OpenGL context, so we save/restore it to make it easier to paste this code elsewhere.
+        //  For this specific demo app we could also call SDL_GL_MakeCurrent(window, gl_context) directly)
+        if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+        {
+            SDL_Window* backup_current_window = SDL_GL_GetCurrentWindow();
+            SDL_GLContext backup_current_context = SDL_GL_GetCurrentContext();
+            ImGui::UpdatePlatformWindows();
+            ImGui::RenderPlatformWindowsDefault();
+            SDL_GL_MakeCurrent(backup_current_window, backup_current_context);
+        }
+
         SDL_GL_SwapWindow(window);
     }
 

examples/example_sdl2_opengl3/Makefile.emscripten

@@ -36,6 +36,9 @@ EMS += -s USE_SDL=2
 EMS += -s DISABLE_EXCEPTION_CATCHING=1
 LDFLAGS += -s WASM=1 -s ALLOW_MEMORY_GROWTH=1 -s NO_EXIT_RUNTIME=0 -s ASSERTIONS=1
 
+# Build as single file (binary text encoded in .html file)
+#LDFLAGS += -sSINGLE_FILE
+
 # Uncomment next line to fix possible rendering bugs with Emscripten version older then 1.39.0 (https://github.com/ocornut/imgui/issues/2877)
 #EMS += -s BINARYEN_TRAP_MODE=clamp
 #EMS += -s SAFE_HEAP=1    ## Adds overhead

examples/example_sdl2_opengl3/main.cpp

@@ -35,12 +35,19 @@ int main(int, char**)
 
     // Decide GL+GLSL versions
 #if defined(IMGUI_IMPL_OPENGL_ES2)
-    // GL ES 2.0 + GLSL 100
+    // GL ES 2.0 + GLSL 100 (WebGL 1.0)
     const char* glsl_version = "#version 100";
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, 0);
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_ES);
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 2);
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);
+#elif defined(IMGUI_IMPL_OPENGL_ES3)
+    // GL ES 3.0 + GLSL 300 es (WebGL 2.0)
+    const char* glsl_version = "#version 300 es";
+    SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, 0);
+    SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_ES);
+    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
+    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);
 #elif defined(__APPLE__)
     // GL 3.2 Core + GLSL 150
     const char* glsl_version = "#version 150";
@@ -75,6 +82,12 @@ int main(int, char**)
     }
 
     SDL_GLContext gl_context = SDL_GL_CreateContext(window);
+    if (gl_context == nullptr)
+    {
+        printf("Error: SDL_GL_CreateContext(): %s\n", SDL_GetError());
+        return -1;
+    }
+    
     SDL_GL_MakeCurrent(window, gl_context);
     SDL_GL_SetSwapInterval(1); // Enable vsync
 
@@ -84,11 +97,23 @@ int main(int, char**)
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
+    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;       // Enable Multi-Viewport / Platform Windows
+    //io.ConfigViewportsNoAutoMerge = true;
+    //io.ConfigViewportsNoTaskBarIcon = true;
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsLight();
 
+    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
+    ImGuiStyle& style = ImGui::GetStyle();
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        style.WindowRounding = 0.0f;
+        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
+    }
+
     // Setup Platform/Renderer backends
     ImGui_ImplSDL2_InitForOpenGL(window, gl_context);
     ImGui_ImplOpenGL3_Init(glsl_version);
@@ -140,6 +165,11 @@ int main(int, char**)
             if (event.type == SDL_WINDOWEVENT && event.window.event == SDL_WINDOWEVENT_CLOSE && event.window.windowID == SDL_GetWindowID(window))
                 done = true;
         }
+        if (SDL_GetWindowFlags(window) & SDL_WINDOW_MINIMIZED)
+        {
+            SDL_Delay(10);
+            continue;
+        }
 
         // Start the Dear ImGui frame
         ImGui_ImplOpenGL3_NewFrame();
@@ -189,6 +219,19 @@ int main(int, char**)
         glClearColor(clear_color.x * clear_color.w, clear_color.y * clear_color.w, clear_color.z * clear_color.w, clear_color.w);
         glClear(GL_COLOR_BUFFER_BIT);
         ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
+
+        // Update and Render additional Platform Windows
+        // (Platform functions may change the current OpenGL context, so we save/restore it to make it easier to paste this code elsewhere.
+        //  For this specific demo app we could also call SDL_GL_MakeCurrent(window, gl_context) directly)
+        if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+        {
+            SDL_Window* backup_current_window = SDL_GL_GetCurrentWindow();
+            SDL_GLContext backup_current_context = SDL_GL_GetCurrentContext();
+            ImGui::UpdatePlatformWindows();
+            ImGui::RenderPlatformWindowsDefault();
+            SDL_GL_MakeCurrent(backup_current_window, backup_current_context);
+        }
+
         SDL_GL_SwapWindow(window);
     }
 #ifdef __EMSCRIPTEN__

examples/example_sdl2_sdlrenderer2/main.cpp

@@ -47,7 +47,7 @@ int main(int, char**)
     if (renderer == nullptr)
     {
         SDL_Log("Error creating SDL_Renderer!");
-        return 0;
+        return -1;
     }
     //SDL_RendererInfo info;
     //SDL_GetRendererInfo(renderer, &info);
@@ -59,6 +59,7 @@ int main(int, char**)
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
@@ -107,6 +108,11 @@ int main(int, char**)
             if (event.type == SDL_WINDOWEVENT && event.window.event == SDL_WINDOWEVENT_CLOSE && event.window.windowID == SDL_GetWindowID(window))
                 done = true;
         }
+        if (SDL_GetWindowFlags(window) & SDL_WINDOW_MINIMIZED)
+        {
+            SDL_Delay(10);
+            continue;
+        }
 
         // Start the Dear ImGui frame
         ImGui_ImplSDLRenderer2_NewFrame();

examples/example_sdl2_vulkan/build_win32.bat

@@ -7,4 +7,8 @@
 
 @set OUT_DIR=Debug
 mkdir %OUT_DIR%
-cl /nologo /Zi /MD /utf-8 %INCLUDES% /D ImTextureID=ImU64 %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS% /subsystem:console
+cl /nologo /Zi /MD /utf-8 %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS% /subsystem:console
+
+@set OUT_DIR=Release
+@REM mkdir %OUT_DIR%
+@REM cl /nologo /Zi /MD /utf-8 /Ox /Oi %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS% /subsystem:console

examples/example_sdl2_vulkan/build_win64.bat

@@ -0,0 +1,14 @@
+@REM Build for Visual Studio compiler. Run your copy of vcvars64.bat or vcvarsall.bat to setup command-line compiler.
+
+@set OUT_EXE=example_sdl2_vulkan
+@set INCLUDES=/I..\.. /I..\..\backends /I%SDL2_DIR%\include /I %VULKAN_SDK%\include
+@set SOURCES=main.cpp ..\..\backends\imgui_impl_sdl2.cpp ..\..\backends\imgui_impl_vulkan.cpp ..\..\imgui*.cpp
+@set LIBS=/LIBPATH:%SDL2_DIR%\lib\x64 /libpath:%VULKAN_SDK%\lib SDL2.lib SDL2main.lib shell32.lib vulkan-1.lib
+
+@set OUT_DIR=Debug
+mkdir %OUT_DIR%
+cl /nologo /Zi /MD /utf-8 %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS% /subsystem:console
+
+@set OUT_DIR=Release
+@REM mkdir %OUT_DIR%
+@REM cl /nologo /Zi /MD /utf-8 /Ox /Oi %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS% /subsystem:console

examples/example_sdl2_vulkan/example_sdl2_vulkan.vcxproj

@@ -91,7 +91,7 @@
       <WarningLevel>Level4</WarningLevel>
       <Optimization>Disabled</Optimization>
       <AdditionalIncludeDirectories>..\..;..\..\backends;%VULKAN_SDK%\include;%SDL2_DIR%\include;$(VcpkgCurrentInstalledDir)include\SDL2;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>ImTextureID=ImU64;_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
     </ClCompile>
     <Link>
@@ -107,7 +107,7 @@
       <WarningLevel>Level4</WarningLevel>
       <Optimization>Disabled</Optimization>
       <AdditionalIncludeDirectories>..\..;..\..\backends;%VULKAN_SDK%\include;%SDL2_DIR%\include;$(VcpkgCurrentInstalledDir)include\SDL2;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>ImTextureID=ImU64;_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
     </ClCompile>
     <Link>
@@ -126,7 +126,7 @@
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <AdditionalIncludeDirectories>..\..;..\..\backends;%VULKAN_SDK%\include;%SDL2_DIR%\include;$(VcpkgCurrentInstalledDir)include\SDL2;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <BufferSecurityCheck>false</BufferSecurityCheck>
-      <PreprocessorDefinitions>ImTextureID=ImU64;_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
     </ClCompile>
     <Link>
@@ -148,7 +148,7 @@
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <AdditionalIncludeDirectories>..\..;..\..\backends;%VULKAN_SDK%\include;%SDL2_DIR%\include;$(VcpkgCurrentInstalledDir)include\SDL2;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <BufferSecurityCheck>false</BufferSecurityCheck>
-      <PreprocessorDefinitions>ImTextureID=ImU64;_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
     </ClCompile>
     <Link>
@@ -187,4 +187,4 @@
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">
   </ImportGroup>
-</Project>
+</Project>

examples/example_sdl2_vulkan/main.cpp

@@ -24,7 +24,7 @@
 // Volk headers
 #ifdef IMGUI_IMPL_VULKAN_USE_VOLK
 #define VOLK_IMPLEMENTATION
-#include <Volk/volk.h>
+#include <volk.h>
 #endif
 
 //#define APP_USE_UNLIMITED_FRAME_RATE
@@ -429,11 +429,23 @@ int main(int, char**)
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
+    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;       // Enable Multi-Viewport / Platform Windows
+    //io.ConfigFlags |= ImGuiConfigFlags_ViewportsNoTaskBarIcons;
+    //io.ConfigFlags |= ImGuiConfigFlags_ViewportsNoMerge;
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsLight();
 
+    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
+    ImGuiStyle& style = ImGui::GetStyle();
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        style.WindowRounding = 0.0f;
+        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
+    }
+
     // Setup Platform/Renderer backends
     ImGui_ImplSDL2_InitForVulkan(window);
     ImGui_ImplVulkan_InitInfo init_info = {};
@@ -492,19 +504,21 @@ int main(int, char**)
             if (event.type == SDL_WINDOWEVENT && event.window.event == SDL_WINDOWEVENT_CLOSE && event.window.windowID == SDL_GetWindowID(window))
                 done = true;
         }
+        if (SDL_GetWindowFlags(window) & SDL_WINDOW_MINIMIZED)
+        {
+            SDL_Delay(10);
+            continue;
+        }
 
         // Resize swap chain?
-        if (g_SwapChainRebuild)
+        int fb_width, fb_height;
+        SDL_GetWindowSize(window, &fb_width, &fb_height);
+        if (fb_width > 0 && fb_height > 0 && (g_SwapChainRebuild || g_MainWindowData.Width != fb_width || g_MainWindowData.Height != fb_height))
         {
-            int width, height;
-            SDL_GetWindowSize(window, &width, &height);
-            if (width > 0 && height > 0)
-            {
-                ImGui_ImplVulkan_SetMinImageCount(g_MinImageCount);
-                ImGui_ImplVulkanH_CreateOrResizeWindow(g_Instance, g_PhysicalDevice, g_Device, &g_MainWindowData, g_QueueFamily, g_Allocator, width, height, g_MinImageCount);
-                g_MainWindowData.FrameIndex = 0;
-                g_SwapChainRebuild = false;
-            }
+            ImGui_ImplVulkan_SetMinImageCount(g_MinImageCount);
+            ImGui_ImplVulkanH_CreateOrResizeWindow(g_Instance, g_PhysicalDevice, g_Device, &g_MainWindowData, g_QueueFamily, g_Allocator, fb_width, fb_height, g_MinImageCount);
+            g_MainWindowData.FrameIndex = 0;
+            g_SwapChainRebuild = false;
         }
 
         // Start the Dear ImGui frame
@@ -551,17 +565,25 @@ int main(int, char**)
 
         // Rendering
         ImGui::Render();
-        ImDrawData* draw_data = ImGui::GetDrawData();
-        const bool is_minimized = (draw_data->DisplaySize.x <= 0.0f || draw_data->DisplaySize.y <= 0.0f);
-        if (!is_minimized)
+        ImDrawData* main_draw_data = ImGui::GetDrawData();
+        const bool main_is_minimized = (main_draw_data->DisplaySize.x <= 0.0f || main_draw_data->DisplaySize.y <= 0.0f);
+        wd->ClearValue.color.float32[0] = clear_color.x * clear_color.w;
+        wd->ClearValue.color.float32[1] = clear_color.y * clear_color.w;
+        wd->ClearValue.color.float32[2] = clear_color.z * clear_color.w;
+        wd->ClearValue.color.float32[3] = clear_color.w;
+        if (!main_is_minimized)
+            FrameRender(wd, main_draw_data);
+
+        // Update and Render additional Platform Windows
+        if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
         {
-            wd->ClearValue.color.float32[0] = clear_color.x * clear_color.w;
-            wd->ClearValue.color.float32[1] = clear_color.y * clear_color.w;
-            wd->ClearValue.color.float32[2] = clear_color.z * clear_color.w;
-            wd->ClearValue.color.float32[3] = clear_color.w;
-            FrameRender(wd, draw_data);
-            FramePresent(wd);
+            ImGui::UpdatePlatformWindows();
+            ImGui::RenderPlatformWindowsDefault();
         }
+
+        // Present Main Platform Window
+        if (!main_is_minimized)
+            FramePresent(wd);
     }
 
     // Cleanup

examples/example_sdl3_opengl3/Makefile.emscripten

@@ -40,6 +40,9 @@ EMS += -s USE_SDL=2
 EMS += -s DISABLE_EXCEPTION_CATCHING=1
 LDFLAGS += -s WASM=1 -s ALLOW_MEMORY_GROWTH=1 -s NO_EXIT_RUNTIME=0 -s ASSERTIONS=1
 
+# Build as single file (binary text encoded in .html file)
+#LDFLAGS += -sSINGLE_FILE
+
 # Uncomment next line to fix possible rendering bugs with Emscripten version older then 1.39.0 (https://github.com/ocornut/imgui/issues/2877)
 #EMS += -s BINARYEN_TRAP_MODE=clamp
 #EMS += -s SAFE_HEAP=1    ## Adds overhead

examples/example_sdl3_opengl3/README.md

@@ -9,11 +9,11 @@ Use the provided project file (.vcxproj). Add to solution (imgui_examples.sln) i
 
 Use build_win32.bat or directly:
 ```
-set SDL2_DIR=path_to_your_sdl3_folder
-cl /Zi /MD /utf-8 /I.. /I..\.. /I%SDL2_DIR%\include main.cpp ..\..\backends\imgui_impl_sdl3.cpp ..\..\backends\imgui_impl_opengl3.cpp ..\..\imgui*.cpp /FeDebug/example_sdl3_opengl3.exe /FoDebug/ /link /libpath:%SDL2_DIR%\lib\x86 SDL3.lib opengl32.lib /subsystem:console
+set SDL3_DIR=path_to_your_sdl3_folder
+cl /Zi /MD /utf-8 /I.. /I..\.. /I%SDL3_DIR%\include main.cpp ..\..\backends\imgui_impl_sdl3.cpp ..\..\backends\imgui_impl_opengl3.cpp ..\..\imgui*.cpp /FeDebug/example_sdl3_opengl3.exe /FoDebug/ /link /libpath:%SDL3_DIR%\lib\x86 SDL3.lib opengl32.lib /subsystem:console
 #                 ^^ include paths     ^^ source files                                                                                    ^^ output exe                    ^^ output dir   ^^ libraries
 # or for 64-bit:
-cl /Zi /MD /utf-8 /I.. /I..\.. /I%SDL2_DIR%\include main.cpp ..\..\backends\imgui_impl_sdl3.cpp ..\..\backends\imgui_impl_opengl3.cpp ..\..\imgui*.cpp /FeDebug/example_sdl3_opengl3.exe /FoDebug/ /link /libpath:%SDL2_DIR%\lib\x64 SDL3.lib SDL2mainopengl32.lib /subsystem:console
+cl /Zi /MD /utf-8 /I.. /I..\.. /I%SDL3_DIR%\include main.cpp ..\..\backends\imgui_impl_sdl3.cpp ..\..\backends\imgui_impl_opengl3.cpp ..\..\imgui*.cpp /FeDebug/example_sdl3_opengl3.exe /FoDebug/ /link /libpath:%SDL3_DIR%\lib\x64 SDL3.lib SDL2mainopengl32.lib /subsystem:console
 ```
 
 ## Linux and similar Unixes

examples/example_sdl3_opengl3/build_win32.bat

@@ -1,8 +1,14 @@
 @REM Build for Visual Studio compiler. Run your copy of vcvars32.bat or vcvarsall.bat to setup command-line compiler.
-@set OUT_DIR=Debug
+
 @set OUT_EXE=example_sdl3_opengl3
 @set INCLUDES=/I..\.. /I..\..\backends /I%SDL3_DIR%\include
 @set SOURCES=main.cpp ..\..\backends\imgui_impl_sdl3.cpp ..\..\backends\imgui_impl_opengl3.cpp ..\..\imgui*.cpp
 @set LIBS=/LIBPATH:%SDL3_DIR%\lib\x86 SDL3.lib opengl32.lib shell32.lib
+
+@set OUT_DIR=Debug
 mkdir %OUT_DIR%
 cl /nologo /Zi /MD /utf-8 %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS% /subsystem:console
+
+@set OUT_DIR=Release
+@REM mkdir %OUT_DIR%
+@REM cl /nologo /Zi /MD /utf-8 /Ox /Oi %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS% /subsystem:console

examples/example_sdl3_opengl3/build_win64.bat

@@ -0,0 +1,14 @@
+@REM Build for Visual Studio compiler. Run your copy of vcvars64.bat or vcvarsall.bat to setup command-line compiler.
+
+@set OUT_EXE=example_sdl3_opengl3
+@set INCLUDES=/I..\.. /I..\..\backends /I%SDL3_DIR%\include
+@set SOURCES=main.cpp ..\..\backends\imgui_impl_sdl3.cpp ..\..\backends\imgui_impl_opengl3.cpp ..\..\imgui*.cpp
+@set LIBS=/LIBPATH:%SDL3_DIR%\lib\x64 SDL3.lib opengl32.lib shell32.lib
+
+@set OUT_DIR=Debug
+mkdir %OUT_DIR%
+cl /nologo /Zi /MD /utf-8 %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS% /subsystem:console
+
+@set OUT_DIR=Release
+@REM mkdir %OUT_DIR%
+@REM cl /nologo /Zi /MD /utf-8 /Ox /Oi %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS% /subsystem:console

examples/example_sdl3_opengl3/main.cpp

@@ -27,7 +27,7 @@
 int main(int, char**)
 {
     // Setup SDL
-    if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER | SDL_INIT_GAMEPAD) != 0)
+    if (!SDL_Init(SDL_INIT_VIDEO | SDL_INIT_GAMEPAD))
     {
         printf("Error: SDL_Init(): %s\n", SDL_GetError());
         return -1;
@@ -35,12 +35,19 @@ int main(int, char**)
 
     // Decide GL+GLSL versions
 #if defined(IMGUI_IMPL_OPENGL_ES2)
-    // GL ES 2.0 + GLSL 100
+    // GL ES 2.0 + GLSL 100 (WebGL 1.0)
     const char* glsl_version = "#version 100";
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, 0);
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_ES);
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 2);
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);
+#elif defined(IMGUI_IMPL_OPENGL_ES3)
+    // GL ES 3.0 + GLSL 300 es (WebGL 2.0)
+    const char* glsl_version = "#version 300 es";
+    SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, 0);
+    SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_ES);
+    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
+    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);
 #elif defined(__APPLE__)
     // GL 3.2 Core + GLSL 150
     const char* glsl_version = "#version 150";
@@ -57,9 +64,6 @@ int main(int, char**)
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);
 #endif
 
-    // Enable native IME.
-    SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1");
-
     // Create window with graphics context
     SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
     SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
@@ -73,6 +77,12 @@ int main(int, char**)
     }
     SDL_SetWindowPosition(window, SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED);
     SDL_GLContext gl_context = SDL_GL_CreateContext(window);
+    if (gl_context == nullptr)
+    {
+        printf("Error: SDL_GL_CreateContext(): %s\n", SDL_GetError());
+        return -1;
+    }
+
     SDL_GL_MakeCurrent(window, gl_context);
     SDL_GL_SetSwapInterval(1); // Enable vsync
     SDL_ShowWindow(window);
@@ -83,11 +93,23 @@ int main(int, char**)
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
+    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;       // Enable Multi-Viewport / Platform Windows
+    //io.ConfigViewportsNoAutoMerge = true;
+    //io.ConfigViewportsNoTaskBarIcon = true;
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsLight();
 
+    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
+    ImGuiStyle& style = ImGui::GetStyle();
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        style.WindowRounding = 0.0f;
+        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
+    }
+
     // Setup Platform/Renderer backends
     ImGui_ImplSDL3_InitForOpenGL(window, gl_context);
     ImGui_ImplOpenGL3_Init(glsl_version);
@@ -139,6 +161,11 @@ int main(int, char**)
             if (event.type == SDL_EVENT_WINDOW_CLOSE_REQUESTED && event.window.windowID == SDL_GetWindowID(window))
                 done = true;
         }
+        if (SDL_GetWindowFlags(window) & SDL_WINDOW_MINIMIZED)
+        {
+            SDL_Delay(10);
+            continue;
+        }
 
         // Start the Dear ImGui frame
         ImGui_ImplOpenGL3_NewFrame();
@@ -188,6 +215,19 @@ int main(int, char**)
         glClearColor(clear_color.x * clear_color.w, clear_color.y * clear_color.w, clear_color.z * clear_color.w, clear_color.w);
         glClear(GL_COLOR_BUFFER_BIT);
         ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
+
+        // Update and Render additional Platform Windows
+        // (Platform functions may change the current OpenGL context, so we save/restore it to make it easier to paste this code elsewhere.
+        //  For this specific demo app we could also call SDL_GL_MakeCurrent(window, gl_context) directly)
+        if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+        {
+            SDL_Window* backup_current_window = SDL_GL_GetCurrentWindow();
+            SDL_GLContext backup_current_context = SDL_GL_GetCurrentContext();
+            ImGui::UpdatePlatformWindows();
+            ImGui::RenderPlatformWindowsDefault();
+            SDL_GL_MakeCurrent(backup_current_window, backup_current_context);
+        }
+
         SDL_GL_SwapWindow(window);
     }
 #ifdef __EMSCRIPTEN__
@@ -199,7 +239,7 @@ int main(int, char**)
     ImGui_ImplSDL3_Shutdown();
     ImGui::DestroyContext();
 
-    SDL_GL_DeleteContext(gl_context);
+    SDL_GL_DestroyContext(gl_context);
     SDL_DestroyWindow(window);
     SDL_Quit();
 

examples/example_sdl3_sdlrenderer3/main.cpp

@@ -25,15 +25,12 @@
 int main(int, char**)
 {
     // Setup SDL
-    if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER | SDL_INIT_GAMEPAD) != 0)
+    if (!SDL_Init(SDL_INIT_VIDEO | SDL_INIT_GAMEPAD))
     {
         printf("Error: SDL_Init(): %s\n", SDL_GetError());
         return -1;
     }
 
-    // Enable native IME.
-    SDL_SetHint(SDL_HINT_IME_SHOW_UI, "1");
-
     // Create window with SDL_Renderer graphics context
     Uint32 window_flags = SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE | SDL_WINDOW_HIDDEN;
     SDL_Window* window = SDL_CreateWindow("Dear ImGui SDL3+SDL_Renderer example", 1280, 720, window_flags);
@@ -58,6 +55,7 @@ int main(int, char**)
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
@@ -114,6 +112,11 @@ int main(int, char**)
             if (event.type == SDL_EVENT_WINDOW_CLOSE_REQUESTED && event.window.windowID == SDL_GetWindowID(window))
                 done = true;
         }
+        if (SDL_GetWindowFlags(window) & SDL_WINDOW_MINIMIZED)
+        {
+            SDL_Delay(10);
+            continue;
+        }
 
         // Start the Dear ImGui frame
         ImGui_ImplSDLRenderer3_NewFrame();
@@ -165,6 +168,9 @@ int main(int, char**)
         ImGui_ImplSDLRenderer3_RenderDrawData(ImGui::GetDrawData(), renderer);
         SDL_RenderPresent(renderer);
     }
+#ifdef __EMSCRIPTEN__
+    EMSCRIPTEN_MAINLOOP_END;
+#endif
 
     // Cleanup
     ImGui_ImplSDLRenderer3_Shutdown();

examples/example_sdl3_vulkan/build_win32.bat

@@ -0,0 +1,14 @@
+@REM Build for Visual Studio compiler. Run your copy of vcvars32.bat or vcvarsall.bat to setup command-line compiler.
+
+@set OUT_EXE=example_sdl3_vulkan
+@set INCLUDES=/I..\.. /I..\..\backends /I%SDL3_DIR%\include /I %VULKAN_SDK%\include
+@set SOURCES=main.cpp ..\..\backends\imgui_impl_sdl3.cpp ..\..\backends\imgui_impl_vulkan.cpp ..\..\imgui*.cpp
+@set LIBS=/LIBPATH:%SDL3_DIR%\lib\x86 /libpath:%VULKAN_SDK%\lib32 SDL3.lib shell32.lib vulkan-1.lib
+
+@set OUT_DIR=Debug
+mkdir %OUT_DIR%
+cl /nologo /Zi /MD /utf-8 %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS% /subsystem:console
+
+@set OUT_DIR=Release
+@REM mkdir %OUT_DIR%
+@REM cl /nologo /Zi /MD /utf-8 /Ox /Oi %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS% /subsystem:console

examples/example_sdl3_vulkan/build_win64.bat

@@ -0,0 +1,14 @@
+@REM Build for Visual Studio compiler. Run your copy of vcvars64.bat or vcvarsall.bat to setup command-line compiler.
+
+@set OUT_EXE=example_sdl3_vulkan
+@set INCLUDES=/I..\.. /I..\..\backends /I%SDL3_DIR%\include /I %VULKAN_SDK%\include
+@set SOURCES=main.cpp ..\..\backends\imgui_impl_sdl3.cpp ..\..\backends\imgui_impl_vulkan.cpp ..\..\imgui*.cpp
+@set LIBS=/LIBPATH:%SDL3_DIR%\lib\x64 /libpath:%VULKAN_SDK%\lib SDL3.lib shell32.lib vulkan-1.lib
+
+@set OUT_DIR=Debug
+mkdir %OUT_DIR%
+cl /nologo /Zi /MD /utf-8 %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS% /subsystem:console
+
+@set OUT_DIR=Release
+@REM mkdir %OUT_DIR%
+@REM cl /nologo /Zi /MD /utf-8 /Ox /Oi %INCLUDES% %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS% /subsystem:console

examples/example_sdl3_vulkan/example_sdl3_vulkan.vcxproj

@@ -0,0 +1,190 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project DefaultTargets="Build" ToolsVersion="14.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Debug|Win32">
+      <Configuration>Debug</Configuration>
+      <Platform>Win32</Platform>
+    </ProjectConfiguration>
+    <ProjectConfiguration Include="Debug|x64">
+      <Configuration>Debug</Configuration>
+      <Platform>x64</Platform>
+    </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|Win32">
+      <Configuration>Release</Configuration>
+      <Platform>Win32</Platform>
+    </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|x64">
+      <Configuration>Release</Configuration>
+      <Platform>x64</Platform>
+    </ProjectConfiguration>
+  </ItemGroup>
+  <PropertyGroup Label="Globals">
+    <ProjectGuid>{663A7E89-1E42-4222-921C-177F5B5910DF}</ProjectGuid>
+    <RootNamespace>example_sdl3_vulkan</RootNamespace>
+    <WindowsTargetPlatformVersion>8.1</WindowsTargetPlatformVersion>
+  </PropertyGroup>
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.Default.props" />
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <UseDebugLibraries>true</UseDebugLibraries>
+    <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v140</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <UseDebugLibraries>true</UseDebugLibraries>
+    <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v140</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <UseDebugLibraries>false</UseDebugLibraries>
+    <WholeProgramOptimization>true</WholeProgramOptimization>
+    <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v140</PlatformToolset>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <UseDebugLibraries>false</UseDebugLibraries>
+    <WholeProgramOptimization>true</WholeProgramOptimization>
+    <CharacterSet>MultiByte</CharacterSet>
+    <PlatformToolset>v140</PlatformToolset>
+  </PropertyGroup>
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
+  <ImportGroup Label="ExtensionSettings">
+  </ImportGroup>
+  <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
+  <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
+  <ImportGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'" Label="PropertySheets">
+    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
+  </ImportGroup>
+  <PropertyGroup Label="UserMacros" />
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
+    <OutDir>$(ProjectDir)$(Configuration)\</OutDir>
+    <IntDir>$(ProjectDir)$(Configuration)\</IntDir>
+    <IncludePath>$(IncludePath)</IncludePath>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
+    <OutDir>$(ProjectDir)$(Configuration)\</OutDir>
+    <IntDir>$(ProjectDir)$(Configuration)\</IntDir>
+    <IncludePath>$(IncludePath)</IncludePath>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
+    <OutDir>$(ProjectDir)$(Configuration)\</OutDir>
+    <IntDir>$(ProjectDir)$(Configuration)\</IntDir>
+    <IncludePath>$(IncludePath)</IncludePath>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'">
+    <OutDir>$(ProjectDir)$(Configuration)\</OutDir>
+    <IntDir>$(ProjectDir)$(Configuration)\</IntDir>
+    <IncludePath>$(IncludePath)</IncludePath>
+  </PropertyGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
+    <ClCompile>
+      <WarningLevel>Level4</WarningLevel>
+      <Optimization>Disabled</Optimization>
+      <AdditionalIncludeDirectories>..\..;..\..\backends;%VULKAN_SDK%\include;%SDL3_DIR%\include;$(VcpkgCurrentInstalledDir)include\SDL3;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <PreprocessorDefinitions>_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
+    </ClCompile>
+    <Link>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalLibraryDirectories>%VULKAN_SDK%\lib32;%SDL3_DIR%\lib\x86;%(AdditionalLibraryDirectories)</AdditionalLibraryDirectories>
+      <AdditionalDependencies>vulkan-1.lib;SDL3.lib;%(AdditionalDependencies)</AdditionalDependencies>
+      <SubSystem>Console</SubSystem>
+      <IgnoreSpecificDefaultLibraries>msvcrt.lib</IgnoreSpecificDefaultLibraries>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
+    <ClCompile>
+      <WarningLevel>Level4</WarningLevel>
+      <Optimization>Disabled</Optimization>
+      <AdditionalIncludeDirectories>..\..;..\..\backends;%VULKAN_SDK%\include;%SDL3_DIR%\include;$(VcpkgCurrentInstalledDir)include\SDL3;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <PreprocessorDefinitions>_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
+    </ClCompile>
+    <Link>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <AdditionalLibraryDirectories>%VULKAN_SDK%\lib;%SDL3_DIR%\lib\x64;%(AdditionalLibraryDirectories)</AdditionalLibraryDirectories>
+      <AdditionalDependencies>vulkan-1.lib;SDL3.lib;%(AdditionalDependencies)</AdditionalDependencies>
+      <SubSystem>Console</SubSystem>
+      <IgnoreSpecificDefaultLibraries>msvcrt.lib</IgnoreSpecificDefaultLibraries>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
+    <ClCompile>
+      <WarningLevel>Level4</WarningLevel>
+      <Optimization>MaxSpeed</Optimization>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <AdditionalIncludeDirectories>..\..;..\..\backends;%VULKAN_SDK%\include;%SDL3_DIR%\include;$(VcpkgCurrentInstalledDir)include\SDL3;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <BufferSecurityCheck>false</BufferSecurityCheck>
+      <PreprocessorDefinitions>_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
+    </ClCompile>
+    <Link>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <AdditionalLibraryDirectories>%VULKAN_SDK%\lib32;%SDL3_DIR%\lib\x86;%(AdditionalLibraryDirectories)</AdditionalLibraryDirectories>
+      <AdditionalDependencies>vulkan-1.lib;SDL3.lib;%(AdditionalDependencies)</AdditionalDependencies>
+      <SubSystem>Console</SubSystem>
+      <IgnoreSpecificDefaultLibraries>
+      </IgnoreSpecificDefaultLibraries>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'">
+    <ClCompile>
+      <WarningLevel>Level4</WarningLevel>
+      <Optimization>MaxSpeed</Optimization>
+      <FunctionLevelLinking>true</FunctionLevelLinking>
+      <IntrinsicFunctions>true</IntrinsicFunctions>
+      <AdditionalIncludeDirectories>..\..;..\..\backends;%VULKAN_SDK%\include;%SDL3_DIR%\include;$(VcpkgCurrentInstalledDir)include\SDL3;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
+      <BufferSecurityCheck>false</BufferSecurityCheck>
+      <PreprocessorDefinitions>_MBCS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
+    </ClCompile>
+    <Link>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
+      <EnableCOMDATFolding>true</EnableCOMDATFolding>
+      <OptimizeReferences>true</OptimizeReferences>
+      <AdditionalLibraryDirectories>%VULKAN_SDK%\lib;%SDL3_DIR%\lib\x64;%(AdditionalLibraryDirectories)</AdditionalLibraryDirectories>
+      <AdditionalDependencies>vulkan-1.lib;SDL3.lib;%(AdditionalDependencies)</AdditionalDependencies>
+      <SubSystem>Console</SubSystem>
+      <IgnoreSpecificDefaultLibraries>
+      </IgnoreSpecificDefaultLibraries>
+    </Link>
+  </ItemDefinitionGroup>
+  <ItemGroup>
+    <ClCompile Include="..\..\imgui.cpp" />
+    <ClCompile Include="..\..\imgui_demo.cpp" />
+    <ClCompile Include="..\..\imgui_draw.cpp" />
+    <ClCompile Include="..\..\imgui_tables.cpp" />
+    <ClCompile Include="..\..\imgui_widgets.cpp" />
+    <ClCompile Include="..\..\backends\imgui_impl_sdl3.cpp" />
+    <ClCompile Include="..\..\backends\imgui_impl_vulkan.cpp" />
+    <ClCompile Include="main.cpp" />
+  </ItemGroup>
+  <ItemGroup>
+    <ClInclude Include="..\..\imconfig.h" />
+    <ClInclude Include="..\..\imgui.h" />
+    <ClInclude Include="..\..\imgui_internal.h" />
+    <ClInclude Include="..\..\backends\imgui_impl_sdl3.h" />
+    <ClInclude Include="..\..\backends\imgui_impl_vulkan.h" />
+  </ItemGroup>
+  <ItemGroup>
+    <None Include="..\..\misc\debuggers\imgui.natstepfilter" />
+    <None Include="..\..\misc\debuggers\imgui.natvis" />
+    <None Include="..\README.txt" />
+  </ItemGroup>
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
+  <ImportGroup Label="ExtensionTargets">
+  </ImportGroup>
+</Project>

examples/example_sdl3_vulkan/example_sdl3_vulkan.vcxproj.filters

@@ -0,0 +1,64 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <ItemGroup>
+    <Filter Include="imgui">
+      <UniqueIdentifier>{20b90ce4-7fcb-4731-b9a0-075f875de82d}</UniqueIdentifier>
+    </Filter>
+    <Filter Include="sources">
+      <UniqueIdentifier>{f18ab499-84e1-499f-8eff-9754361e0e52}</UniqueIdentifier>
+      <Extensions>cpp;c;cc;cxx;def;odl;idl;hpj;bat;asm;asmx</Extensions>
+    </Filter>
+  </ItemGroup>
+  <ItemGroup>
+    <ClCompile Include="..\..\imgui.cpp">
+      <Filter>imgui</Filter>
+    </ClCompile>
+    <ClCompile Include="..\..\imgui_demo.cpp">
+      <Filter>imgui</Filter>
+    </ClCompile>
+    <ClCompile Include="..\..\imgui_draw.cpp">
+      <Filter>imgui</Filter>
+    </ClCompile>
+    <ClCompile Include="..\..\backends\imgui_impl_sdl3.cpp">
+      <Filter>sources</Filter>
+    </ClCompile>
+    <ClCompile Include="main.cpp">
+      <Filter>sources</Filter>
+    </ClCompile>
+    <ClCompile Include="..\..\backends\imgui_impl_vulkan.cpp">
+      <Filter>sources</Filter>
+    </ClCompile>
+    <ClCompile Include="..\..\imgui_widgets.cpp">
+      <Filter>imgui</Filter>
+    </ClCompile>
+    <ClCompile Include="..\..\imgui_tables.cpp">
+      <Filter>imgui</Filter>
+    </ClCompile>
+  </ItemGroup>
+  <ItemGroup>
+    <ClInclude Include="..\..\imconfig.h">
+      <Filter>imgui</Filter>
+    </ClInclude>
+    <ClInclude Include="..\..\imgui.h">
+      <Filter>imgui</Filter>
+    </ClInclude>
+    <ClInclude Include="..\..\imgui_internal.h">
+      <Filter>imgui</Filter>
+    </ClInclude>
+    <ClInclude Include="..\..\backends\imgui_impl_sdl3.h">
+      <Filter>sources</Filter>
+    </ClInclude>
+    <ClInclude Include="..\..\backends\imgui_impl_vulkan.h">
+      <Filter>sources</Filter>
+    </ClInclude>
+  </ItemGroup>
+  <ItemGroup>
+    <None Include="..\README.txt" />
+    <None Include="..\..\misc\debuggers\imgui.natvis">
+      <Filter>imgui</Filter>
+    </None>
+    <None Include="..\..\misc\debuggers\imgui.natstepfilter">
+      <Filter>imgui</Filter>
+    </None>
+  </ItemGroup>
+</Project>

examples/example_sdl3_vulkan/main.cpp

@@ -0,0 +1,607 @@
+// Dear ImGui: standalone example application for SDL3 + Vulkan
+
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
+
+// Important note to the reader who wish to integrate imgui_impl_vulkan.cpp/.h in their own engine/app.
+// - Common ImGui_ImplVulkan_XXX functions and structures are used to interface with imgui_impl_vulkan.cpp/.h.
+//   You will use those if you want to use this rendering backend in your engine/app.
+// - Helper ImGui_ImplVulkanH_XXX functions and structures are only used by this example (main.cpp) and by
+//   the backend itself (imgui_impl_vulkan.cpp), but should PROBABLY NOT be used by your own engine/app code.
+// Read comments in imgui_impl_vulkan.h.
+
+#include "imgui.h"
+#include "imgui_impl_sdl3.h"
+#include "imgui_impl_vulkan.h"
+#include <stdio.h>          // printf, fprintf
+#include <stdlib.h>         // abort
+#include <SDL3/SDL.h>
+#include <SDL3/SDL_vulkan.h>
+
+// This example doesn't compile with Emscripten yet! Awaiting SDL3 support.
+#ifdef __EMSCRIPTEN__
+#include "../libs/emscripten/emscripten_mainloop_stub.h"
+#endif
+
+// Volk headers
+#ifdef IMGUI_IMPL_VULKAN_USE_VOLK
+#define VOLK_IMPLEMENTATION
+#include <volk.h>
+#endif
+
+//#define APP_USE_UNLIMITED_FRAME_RATE
+#ifdef _DEBUG
+#define APP_USE_VULKAN_DEBUG_REPORT
+#endif
+
+// Data
+static VkAllocationCallbacks*   g_Allocator = nullptr;
+static VkInstance               g_Instance = VK_NULL_HANDLE;
+static VkPhysicalDevice         g_PhysicalDevice = VK_NULL_HANDLE;
+static VkDevice                 g_Device = VK_NULL_HANDLE;
+static uint32_t                 g_QueueFamily = (uint32_t)-1;
+static VkQueue                  g_Queue = VK_NULL_HANDLE;
+static VkDebugReportCallbackEXT g_DebugReport = VK_NULL_HANDLE;
+static VkPipelineCache          g_PipelineCache = VK_NULL_HANDLE;
+static VkDescriptorPool         g_DescriptorPool = VK_NULL_HANDLE;
+
+static ImGui_ImplVulkanH_Window g_MainWindowData;
+static uint32_t                 g_MinImageCount = 2;
+static bool                     g_SwapChainRebuild = false;
+
+static void check_vk_result(VkResult err)
+{
+    if (err == 0)
+        return;
+    fprintf(stderr, "[vulkan] Error: VkResult = %d\n", err);
+    if (err < 0)
+        abort();
+}
+
+#ifdef APP_USE_VULKAN_DEBUG_REPORT
+static VKAPI_ATTR VkBool32 VKAPI_CALL debug_report(VkDebugReportFlagsEXT flags, VkDebugReportObjectTypeEXT objectType, uint64_t object, size_t location, int32_t messageCode, const char* pLayerPrefix, const char* pMessage, void* pUserData)
+{
+    (void)flags; (void)object; (void)location; (void)messageCode; (void)pUserData; (void)pLayerPrefix; // Unused arguments
+    fprintf(stderr, "[vulkan] Debug report from ObjectType: %i\nMessage: %s\n\n", objectType, pMessage);
+    return VK_FALSE;
+}
+#endif // APP_USE_VULKAN_DEBUG_REPORT
+
+static bool IsExtensionAvailable(const ImVector<VkExtensionProperties>& properties, const char* extension)
+{
+    for (const VkExtensionProperties& p : properties)
+        if (strcmp(p.extensionName, extension) == 0)
+            return true;
+    return false;
+}
+
+static VkPhysicalDevice SetupVulkan_SelectPhysicalDevice()
+{
+    uint32_t gpu_count;
+    VkResult err = vkEnumeratePhysicalDevices(g_Instance, &gpu_count, nullptr);
+    check_vk_result(err);
+    IM_ASSERT(gpu_count > 0);
+
+    ImVector<VkPhysicalDevice> gpus;
+    gpus.resize(gpu_count);
+    err = vkEnumeratePhysicalDevices(g_Instance, &gpu_count, gpus.Data);
+    check_vk_result(err);
+
+    // If a number >1 of GPUs got reported, find discrete GPU if present, or use first one available. This covers
+    // most common cases (multi-gpu/integrated+dedicated graphics). Handling more complicated setups (multiple
+    // dedicated GPUs) is out of scope of this sample.
+    for (VkPhysicalDevice& device : gpus)
+    {
+        VkPhysicalDeviceProperties properties;
+        vkGetPhysicalDeviceProperties(device, &properties);
+        if (properties.deviceType == VK_PHYSICAL_DEVICE_TYPE_DISCRETE_GPU)
+            return device;
+    }
+
+    // Use first GPU (Integrated) is a Discrete one is not available.
+    if (gpu_count > 0)
+        return gpus[0];
+    return VK_NULL_HANDLE;
+}
+
+static void SetupVulkan(ImVector<const char*> instance_extensions)
+{
+    VkResult err;
+#ifdef IMGUI_IMPL_VULKAN_USE_VOLK
+    volkInitialize();
+#endif
+
+    // Create Vulkan Instance
+    {
+        VkInstanceCreateInfo create_info = {};
+        create_info.sType = VK_STRUCTURE_TYPE_INSTANCE_CREATE_INFO;
+
+        // Enumerate available extensions
+        uint32_t properties_count;
+        ImVector<VkExtensionProperties> properties;
+        vkEnumerateInstanceExtensionProperties(nullptr, &properties_count, nullptr);
+        properties.resize(properties_count);
+        err = vkEnumerateInstanceExtensionProperties(nullptr, &properties_count, properties.Data);
+        check_vk_result(err);
+
+        // Enable required extensions
+        if (IsExtensionAvailable(properties, VK_KHR_GET_PHYSICAL_DEVICE_PROPERTIES_2_EXTENSION_NAME))
+            instance_extensions.push_back(VK_KHR_GET_PHYSICAL_DEVICE_PROPERTIES_2_EXTENSION_NAME);
+#ifdef VK_KHR_PORTABILITY_ENUMERATION_EXTENSION_NAME
+        if (IsExtensionAvailable(properties, VK_KHR_PORTABILITY_ENUMERATION_EXTENSION_NAME))
+        {
+            instance_extensions.push_back(VK_KHR_PORTABILITY_ENUMERATION_EXTENSION_NAME);
+            create_info.flags |= VK_INSTANCE_CREATE_ENUMERATE_PORTABILITY_BIT_KHR;
+        }
+#endif
+
+        // Enabling validation layers
+#ifdef APP_USE_VULKAN_DEBUG_REPORT
+        const char* layers[] = { "VK_LAYER_KHRONOS_validation" };
+        create_info.enabledLayerCount = 1;
+        create_info.ppEnabledLayerNames = layers;
+        instance_extensions.push_back("VK_EXT_debug_report");
+#endif
+
+        // Create Vulkan Instance
+        create_info.enabledExtensionCount = (uint32_t)instance_extensions.Size;
+        create_info.ppEnabledExtensionNames = instance_extensions.Data;
+        err = vkCreateInstance(&create_info, g_Allocator, &g_Instance);
+        check_vk_result(err);
+#ifdef IMGUI_IMPL_VULKAN_USE_VOLK
+        volkLoadInstance(g_Instance);
+#endif
+
+        // Setup the debug report callback
+#ifdef APP_USE_VULKAN_DEBUG_REPORT
+        auto f_vkCreateDebugReportCallbackEXT = (PFN_vkCreateDebugReportCallbackEXT)vkGetInstanceProcAddr(g_Instance, "vkCreateDebugReportCallbackEXT");
+        IM_ASSERT(f_vkCreateDebugReportCallbackEXT != nullptr);
+        VkDebugReportCallbackCreateInfoEXT debug_report_ci = {};
+        debug_report_ci.sType = VK_STRUCTURE_TYPE_DEBUG_REPORT_CALLBACK_CREATE_INFO_EXT;
+        debug_report_ci.flags = VK_DEBUG_REPORT_ERROR_BIT_EXT | VK_DEBUG_REPORT_WARNING_BIT_EXT | VK_DEBUG_REPORT_PERFORMANCE_WARNING_BIT_EXT;
+        debug_report_ci.pfnCallback = debug_report;
+        debug_report_ci.pUserData = nullptr;
+        err = f_vkCreateDebugReportCallbackEXT(g_Instance, &debug_report_ci, g_Allocator, &g_DebugReport);
+        check_vk_result(err);
+#endif
+    }
+
+    // Select Physical Device (GPU)
+    g_PhysicalDevice = SetupVulkan_SelectPhysicalDevice();
+
+    // Select graphics queue family
+    {
+        uint32_t count;
+        vkGetPhysicalDeviceQueueFamilyProperties(g_PhysicalDevice, &count, nullptr);
+        VkQueueFamilyProperties* queues = (VkQueueFamilyProperties*)malloc(sizeof(VkQueueFamilyProperties) * count);
+        vkGetPhysicalDeviceQueueFamilyProperties(g_PhysicalDevice, &count, queues);
+        for (uint32_t i = 0; i < count; i++)
+            if (queues[i].queueFlags & VK_QUEUE_GRAPHICS_BIT)
+            {
+                g_QueueFamily = i;
+                break;
+            }
+        free(queues);
+        IM_ASSERT(g_QueueFamily != (uint32_t)-1);
+    }
+
+    // Create Logical Device (with 1 queue)
+    {
+        ImVector<const char*> device_extensions;
+        device_extensions.push_back("VK_KHR_swapchain");
+
+        // Enumerate physical device extension
+        uint32_t properties_count;
+        ImVector<VkExtensionProperties> properties;
+        vkEnumerateDeviceExtensionProperties(g_PhysicalDevice, nullptr, &properties_count, nullptr);
+        properties.resize(properties_count);
+        vkEnumerateDeviceExtensionProperties(g_PhysicalDevice, nullptr, &properties_count, properties.Data);
+#ifdef VK_KHR_PORTABILITY_SUBSET_EXTENSION_NAME
+        if (IsExtensionAvailable(properties, VK_KHR_PORTABILITY_SUBSET_EXTENSION_NAME))
+            device_extensions.push_back(VK_KHR_PORTABILITY_SUBSET_EXTENSION_NAME);
+#endif
+
+        const float queue_priority[] = { 1.0f };
+        VkDeviceQueueCreateInfo queue_info[1] = {};
+        queue_info[0].sType = VK_STRUCTURE_TYPE_DEVICE_QUEUE_CREATE_INFO;
+        queue_info[0].queueFamilyIndex = g_QueueFamily;
+        queue_info[0].queueCount = 1;
+        queue_info[0].pQueuePriorities = queue_priority;
+        VkDeviceCreateInfo create_info = {};
+        create_info.sType = VK_STRUCTURE_TYPE_DEVICE_CREATE_INFO;
+        create_info.queueCreateInfoCount = sizeof(queue_info) / sizeof(queue_info[0]);
+        create_info.pQueueCreateInfos = queue_info;
+        create_info.enabledExtensionCount = (uint32_t)device_extensions.Size;
+        create_info.ppEnabledExtensionNames = device_extensions.Data;
+        err = vkCreateDevice(g_PhysicalDevice, &create_info, g_Allocator, &g_Device);
+        check_vk_result(err);
+        vkGetDeviceQueue(g_Device, g_QueueFamily, 0, &g_Queue);
+    }
+
+    // Create Descriptor Pool
+    // The example only requires a single combined image sampler descriptor for the font image and only uses one descriptor set (for that)
+    // If you wish to load e.g. additional textures you may need to alter pools sizes.
+    {
+        VkDescriptorPoolSize pool_sizes[] =
+        {
+            { VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER, 1 },
+        };
+        VkDescriptorPoolCreateInfo pool_info = {};
+        pool_info.sType = VK_STRUCTURE_TYPE_DESCRIPTOR_POOL_CREATE_INFO;
+        pool_info.flags = VK_DESCRIPTOR_POOL_CREATE_FREE_DESCRIPTOR_SET_BIT;
+        pool_info.maxSets = 1;
+        pool_info.poolSizeCount = (uint32_t)IM_ARRAYSIZE(pool_sizes);
+        pool_info.pPoolSizes = pool_sizes;
+        err = vkCreateDescriptorPool(g_Device, &pool_info, g_Allocator, &g_DescriptorPool);
+        check_vk_result(err);
+    }
+}
+
+// All the ImGui_ImplVulkanH_XXX structures/functions are optional helpers used by the demo.
+// Your real engine/app may not use them.
+static void SetupVulkanWindow(ImGui_ImplVulkanH_Window* wd, VkSurfaceKHR surface, int width, int height)
+{
+    wd->Surface = surface;
+
+    // Check for WSI support
+    VkBool32 res;
+    vkGetPhysicalDeviceSurfaceSupportKHR(g_PhysicalDevice, g_QueueFamily, wd->Surface, &res);
+    if (res != VK_TRUE)
+    {
+        fprintf(stderr, "Error no WSI support on physical device 0\n");
+        exit(-1);
+    }
+
+    // Select Surface Format
+    const VkFormat requestSurfaceImageFormat[] = { VK_FORMAT_B8G8R8A8_UNORM, VK_FORMAT_R8G8B8A8_UNORM, VK_FORMAT_B8G8R8_UNORM, VK_FORMAT_R8G8B8_UNORM };
+    const VkColorSpaceKHR requestSurfaceColorSpace = VK_COLORSPACE_SRGB_NONLINEAR_KHR;
+    wd->SurfaceFormat = ImGui_ImplVulkanH_SelectSurfaceFormat(g_PhysicalDevice, wd->Surface, requestSurfaceImageFormat, (size_t)IM_ARRAYSIZE(requestSurfaceImageFormat), requestSurfaceColorSpace);
+
+    // Select Present Mode
+#ifdef APP_UNLIMITED_FRAME_RATE
+    VkPresentModeKHR present_modes[] = { VK_PRESENT_MODE_MAILBOX_KHR, VK_PRESENT_MODE_IMMEDIATE_KHR, VK_PRESENT_MODE_FIFO_KHR };
+#else
+    VkPresentModeKHR present_modes[] = { VK_PRESENT_MODE_FIFO_KHR };
+#endif
+    wd->PresentMode = ImGui_ImplVulkanH_SelectPresentMode(g_PhysicalDevice, wd->Surface, &present_modes[0], IM_ARRAYSIZE(present_modes));
+    //printf("[vulkan] Selected PresentMode = %d\n", wd->PresentMode);
+
+    // Create SwapChain, RenderPass, Framebuffer, etc.
+    IM_ASSERT(g_MinImageCount >= 2);
+    ImGui_ImplVulkanH_CreateOrResizeWindow(g_Instance, g_PhysicalDevice, g_Device, wd, g_QueueFamily, g_Allocator, width, height, g_MinImageCount);
+}
+
+static void CleanupVulkan()
+{
+    vkDestroyDescriptorPool(g_Device, g_DescriptorPool, g_Allocator);
+
+#ifdef APP_USE_VULKAN_DEBUG_REPORT
+    // Remove the debug report callback
+    auto f_vkDestroyDebugReportCallbackEXT = (PFN_vkDestroyDebugReportCallbackEXT)vkGetInstanceProcAddr(g_Instance, "vkDestroyDebugReportCallbackEXT");
+    f_vkDestroyDebugReportCallbackEXT(g_Instance, g_DebugReport, g_Allocator);
+#endif // APP_USE_VULKAN_DEBUG_REPORT
+
+    vkDestroyDevice(g_Device, g_Allocator);
+    vkDestroyInstance(g_Instance, g_Allocator);
+}
+
+static void CleanupVulkanWindow()
+{
+    ImGui_ImplVulkanH_DestroyWindow(g_Instance, g_Device, &g_MainWindowData, g_Allocator);
+}
+
+static void FrameRender(ImGui_ImplVulkanH_Window* wd, ImDrawData* draw_data)
+{
+    VkResult err;
+
+    VkSemaphore image_acquired_semaphore  = wd->FrameSemaphores[wd->SemaphoreIndex].ImageAcquiredSemaphore;
+    VkSemaphore render_complete_semaphore = wd->FrameSemaphores[wd->SemaphoreIndex].RenderCompleteSemaphore;
+    err = vkAcquireNextImageKHR(g_Device, wd->Swapchain, UINT64_MAX, image_acquired_semaphore, VK_NULL_HANDLE, &wd->FrameIndex);
+    if (err == VK_ERROR_OUT_OF_DATE_KHR || err == VK_SUBOPTIMAL_KHR)
+    {
+        g_SwapChainRebuild = true;
+        return;
+    }
+    check_vk_result(err);
+
+    ImGui_ImplVulkanH_Frame* fd = &wd->Frames[wd->FrameIndex];
+    {
+        err = vkWaitForFences(g_Device, 1, &fd->Fence, VK_TRUE, UINT64_MAX);    // wait indefinitely instead of periodically checking
+        check_vk_result(err);
+
+        err = vkResetFences(g_Device, 1, &fd->Fence);
+        check_vk_result(err);
+    }
+    {
+        err = vkResetCommandPool(g_Device, fd->CommandPool, 0);
+        check_vk_result(err);
+        VkCommandBufferBeginInfo info = {};
+        info.sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_BEGIN_INFO;
+        info.flags |= VK_COMMAND_BUFFER_USAGE_ONE_TIME_SUBMIT_BIT;
+        err = vkBeginCommandBuffer(fd->CommandBuffer, &info);
+        check_vk_result(err);
+    }
+    {
+        VkRenderPassBeginInfo info = {};
+        info.sType = VK_STRUCTURE_TYPE_RENDER_PASS_BEGIN_INFO;
+        info.renderPass = wd->RenderPass;
+        info.framebuffer = fd->Framebuffer;
+        info.renderArea.extent.width = wd->Width;
+        info.renderArea.extent.height = wd->Height;
+        info.clearValueCount = 1;
+        info.pClearValues = &wd->ClearValue;
+        vkCmdBeginRenderPass(fd->CommandBuffer, &info, VK_SUBPASS_CONTENTS_INLINE);
+    }
+
+    // Record dear imgui primitives into command buffer
+    ImGui_ImplVulkan_RenderDrawData(draw_data, fd->CommandBuffer);
+
+    // Submit command buffer
+    vkCmdEndRenderPass(fd->CommandBuffer);
+    {
+        VkPipelineStageFlags wait_stage = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT;
+        VkSubmitInfo info = {};
+        info.sType = VK_STRUCTURE_TYPE_SUBMIT_INFO;
+        info.waitSemaphoreCount = 1;
+        info.pWaitSemaphores = &image_acquired_semaphore;
+        info.pWaitDstStageMask = &wait_stage;
+        info.commandBufferCount = 1;
+        info.pCommandBuffers = &fd->CommandBuffer;
+        info.signalSemaphoreCount = 1;
+        info.pSignalSemaphores = &render_complete_semaphore;
+
+        err = vkEndCommandBuffer(fd->CommandBuffer);
+        check_vk_result(err);
+        err = vkQueueSubmit(g_Queue, 1, &info, fd->Fence);
+        check_vk_result(err);
+    }
+}
+
+static void FramePresent(ImGui_ImplVulkanH_Window* wd)
+{
+    if (g_SwapChainRebuild)
+        return;
+    VkSemaphore render_complete_semaphore = wd->FrameSemaphores[wd->SemaphoreIndex].RenderCompleteSemaphore;
+    VkPresentInfoKHR info = {};
+    info.sType = VK_STRUCTURE_TYPE_PRESENT_INFO_KHR;
+    info.waitSemaphoreCount = 1;
+    info.pWaitSemaphores = &render_complete_semaphore;
+    info.swapchainCount = 1;
+    info.pSwapchains = &wd->Swapchain;
+    info.pImageIndices = &wd->FrameIndex;
+    VkResult err = vkQueuePresentKHR(g_Queue, &info);
+    if (err == VK_ERROR_OUT_OF_DATE_KHR || err == VK_SUBOPTIMAL_KHR)
+    {
+        g_SwapChainRebuild = true;
+        return;
+    }
+    check_vk_result(err);
+    wd->SemaphoreIndex = (wd->SemaphoreIndex + 1) % wd->SemaphoreCount; // Now we can use the next set of semaphores
+}
+
+// Main code
+int main(int, char**)
+{
+    // Setup SDL
+    if (!SDL_Init(SDL_INIT_VIDEO | SDL_INIT_GAMEPAD) != 0)
+    {
+        printf("Error: SDL_Init(): %s\n", SDL_GetError());
+        return -1;
+    }
+
+    // Create window with Vulkan graphics context
+    SDL_WindowFlags window_flags = (SDL_WindowFlags)(SDL_WINDOW_VULKAN | SDL_WINDOW_RESIZABLE | SDL_WINDOW_HIGH_PIXEL_DENSITY | SDL_WINDOW_HIDDEN);
+    SDL_Window* window = SDL_CreateWindow("Dear ImGui SDL3+Vulkan example", 1280, 720, window_flags);
+    if (window == nullptr)
+    {
+        printf("Error: SDL_CreateWindow(): %s\n", SDL_GetError());
+        return -1;
+    }
+
+    ImVector<const char*> extensions;
+    {
+        uint32_t sdl_extensions_count = 0;
+        const char* const* sdl_extensions = SDL_Vulkan_GetInstanceExtensions(&sdl_extensions_count);
+        for (uint32_t n = 0; n < sdl_extensions_count; n++)
+            extensions.push_back(sdl_extensions[n]);
+    }
+    SetupVulkan(extensions);
+
+    // Create Window Surface
+    VkSurfaceKHR surface;
+    VkResult err;
+    if (SDL_Vulkan_CreateSurface(window, g_Instance, g_Allocator, &surface) == 0)
+    {
+        printf("Failed to create Vulkan surface.\n");
+        return 1;
+    }
+
+    // Create Framebuffers
+    int w, h;
+    SDL_GetWindowSize(window, &w, &h);
+    ImGui_ImplVulkanH_Window* wd = &g_MainWindowData;
+    SetupVulkanWindow(wd, surface, w, h);
+    SDL_SetWindowPosition(window, SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED);
+    SDL_ShowWindow(window);
+
+    // Setup Dear ImGui context
+    IMGUI_CHECKVERSION();
+    ImGui::CreateContext();
+    ImGuiIO& io = ImGui::GetIO(); (void)io;
+    io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
+    io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
+    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;       // Enable Multi-Viewport / Platform Windows
+    //io.ConfigFlags |= ImGuiConfigFlags_ViewportsNoTaskBarIcons;
+    //io.ConfigFlags |= ImGuiConfigFlags_ViewportsNoMerge;
+
+    // Setup Dear ImGui style
+    ImGui::StyleColorsDark();
+    //ImGui::StyleColorsLight();
+
+    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
+    ImGuiStyle& style = ImGui::GetStyle();
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        style.WindowRounding = 0.0f;
+        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
+    }
+
+    // Setup Platform/Renderer backends
+    ImGui_ImplSDL3_InitForVulkan(window);
+    ImGui_ImplVulkan_InitInfo init_info = {};
+    init_info.Instance = g_Instance;
+    init_info.PhysicalDevice = g_PhysicalDevice;
+    init_info.Device = g_Device;
+    init_info.QueueFamily = g_QueueFamily;
+    init_info.Queue = g_Queue;
+    init_info.PipelineCache = g_PipelineCache;
+    init_info.DescriptorPool = g_DescriptorPool;
+    init_info.RenderPass = wd->RenderPass;
+    init_info.Subpass = 0;
+    init_info.MinImageCount = g_MinImageCount;
+    init_info.ImageCount = wd->ImageCount;
+    init_info.MSAASamples = VK_SAMPLE_COUNT_1_BIT;
+    init_info.Allocator = g_Allocator;
+    init_info.CheckVkResultFn = check_vk_result;
+    ImGui_ImplVulkan_Init(&init_info);
+
+    // Load Fonts
+    // - If no fonts are loaded, dear imgui will use the default font. You can also load multiple fonts and use ImGui::PushFont()/PopFont() to select them.
+    // - AddFontFromFileTTF() will return the ImFont* so you can store it if you need to select the font among multiple.
+    // - If the file cannot be loaded, the function will return a nullptr. Please handle those errors in your application (e.g. use an assertion, or display an error and quit).
+    // - The fonts will be rasterized at a given size (w/ oversampling) and stored into a texture when calling ImFontAtlas::Build()/GetTexDataAsXXXX(), which ImGui_ImplXXXX_NewFrame below will call.
+    // - Use '#define IMGUI_ENABLE_FREETYPE' in your imconfig file to use Freetype for higher quality font rendering.
+    // - Read 'docs/FONTS.md' for more instructions and details.
+    // - Remember that in C/C++ if you want to include a backslash \ in a string literal you need to write a double backslash \\ !
+    //io.Fonts->AddFontDefault();
+    //io.Fonts->AddFontFromFileTTF("c:\\Windows\\Fonts\\segoeui.ttf", 18.0f);
+    //io.Fonts->AddFontFromFileTTF("../../misc/fonts/DroidSans.ttf", 16.0f);
+    //io.Fonts->AddFontFromFileTTF("../../misc/fonts/Roboto-Medium.ttf", 16.0f);
+    //io.Fonts->AddFontFromFileTTF("../../misc/fonts/Cousine-Regular.ttf", 15.0f);
+    //ImFont* font = io.Fonts->AddFontFromFileTTF("c:\\Windows\\Fonts\\ArialUni.ttf", 18.0f, nullptr, io.Fonts->GetGlyphRangesJapanese());
+    //IM_ASSERT(font != nullptr);
+
+    // Our state
+    bool show_demo_window = true;
+    bool show_another_window = false;
+    ImVec4 clear_color = ImVec4(0.45f, 0.55f, 0.60f, 1.00f);
+
+    // Main loop
+    bool done = false;
+    while (!done)
+    {
+        // Poll and handle events (inputs, window resize, etc.)
+        // You can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if dear imgui wants to use your inputs.
+        // - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application, or clear/overwrite your copy of the mouse data.
+        // - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application, or clear/overwrite your copy of the keyboard data.
+        // Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
+        SDL_Event event;
+        while (SDL_PollEvent(&event))
+        {
+            ImGui_ImplSDL3_ProcessEvent(&event);
+            if (event.type == SDL_EVENT_QUIT)
+                done = true;
+            if (event.type == SDL_EVENT_WINDOW_CLOSE_REQUESTED && event.window.windowID == SDL_GetWindowID(window))
+                done = true;
+        }
+        if (SDL_GetWindowFlags(window) & SDL_WINDOW_MINIMIZED)
+        {
+            SDL_Delay(10);
+            continue;
+        }
+
+        // Resize swap chain?
+        int fb_width, fb_height;
+        SDL_GetWindowSize(window, &fb_width, &fb_height);
+        if (fb_width > 0 && fb_height > 0 && (g_SwapChainRebuild || g_MainWindowData.Width != fb_width || g_MainWindowData.Height != fb_height))
+        {
+            ImGui_ImplVulkan_SetMinImageCount(g_MinImageCount);
+            ImGui_ImplVulkanH_CreateOrResizeWindow(g_Instance, g_PhysicalDevice, g_Device, &g_MainWindowData, g_QueueFamily, g_Allocator, fb_width, fb_height, g_MinImageCount);
+            g_MainWindowData.FrameIndex = 0;
+            g_SwapChainRebuild = false;
+        }
+
+        // Start the Dear ImGui frame
+        ImGui_ImplVulkan_NewFrame();
+        ImGui_ImplSDL3_NewFrame();
+        ImGui::NewFrame();
+
+        // 1. Show the big demo window (Most of the sample code is in ImGui::ShowDemoWindow()! You can browse its code to learn more about Dear ImGui!).
+        if (show_demo_window)
+            ImGui::ShowDemoWindow(&show_demo_window);
+
+        // 2. Show a simple window that we create ourselves. We use a Begin/End pair to create a named window.
+        {
+            static float f = 0.0f;
+            static int counter = 0;
+
+            ImGui::Begin("Hello, world!");                          // Create a window called "Hello, world!" and append into it.
+
+            ImGui::Text("This is some useful text.");               // Display some text (you can use a format strings too)
+            ImGui::Checkbox("Demo Window", &show_demo_window);      // Edit bools storing our window open/close state
+            ImGui::Checkbox("Another Window", &show_another_window);
+
+            ImGui::SliderFloat("float", &f, 0.0f, 1.0f);            // Edit 1 float using a slider from 0.0f to 1.0f
+            ImGui::ColorEdit3("clear color", (float*)&clear_color); // Edit 3 floats representing a color
+
+            if (ImGui::Button("Button"))                            // Buttons return true when clicked (most widgets return true when edited/activated)
+                counter++;
+            ImGui::SameLine();
+            ImGui::Text("counter = %d", counter);
+
+            ImGui::Text("Application average %.3f ms/frame (%.1f FPS)", 1000.0f / io.Framerate, io.Framerate);
+            ImGui::End();
+        }
+
+        // 3. Show another simple window.
+        if (show_another_window)
+        {
+            ImGui::Begin("Another Window", &show_another_window);   // Pass a pointer to our bool variable (the window will have a closing button that will clear the bool when clicked)
+            ImGui::Text("Hello from another window!");
+            if (ImGui::Button("Close Me"))
+                show_another_window = false;
+            ImGui::End();
+        }
+
+        // Rendering
+        ImGui::Render();
+        ImDrawData* main_draw_data = ImGui::GetDrawData();
+        const bool main_is_minimized = (main_draw_data->DisplaySize.x <= 0.0f || main_draw_data->DisplaySize.y <= 0.0f);
+        wd->ClearValue.color.float32[0] = clear_color.x * clear_color.w;
+        wd->ClearValue.color.float32[1] = clear_color.y * clear_color.w;
+        wd->ClearValue.color.float32[2] = clear_color.z * clear_color.w;
+        wd->ClearValue.color.float32[3] = clear_color.w;
+        if (!main_is_minimized)
+            FrameRender(wd, main_draw_data);
+
+        // Update and Render additional Platform Windows
+        if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+        {
+            ImGui::UpdatePlatformWindows();
+            ImGui::RenderPlatformWindowsDefault();
+        }
+
+        // Present Main Platform Window
+        if (!main_is_minimized)
+            FramePresent(wd);
+    }
+
+    // Cleanup
+    err = vkDeviceWaitIdle(g_Device);
+    check_vk_result(err);
+    ImGui_ImplVulkan_Shutdown();
+    ImGui_ImplSDL3_Shutdown();
+    ImGui::DestroyContext();
+
+    CleanupVulkanWindow();
+    CleanupVulkan();
+
+    SDL_DestroyWindow(window);
+    SDL_Quit();
+
+    return 0;
+}

examples/example_win32_directx10/main.cpp

@@ -54,11 +54,23 @@ int main(int, char**)
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
+    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;       // Enable Multi-Viewport / Platform Windows
+    //io.ConfigViewportsNoAutoMerge = true;
+    //io.ConfigViewportsNoTaskBarIcon = true;
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsLight();
 
+    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
+    ImGuiStyle& style = ImGui::GetStyle();
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        style.WindowRounding = 0.0f;
+        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
+    }
+
     // Setup Platform/Renderer backends
     ImGui_ImplWin32_Init(hwnd);
     ImGui_ImplDX10_Init(g_pd3dDevice);
@@ -167,6 +179,13 @@ int main(int, char**)
         g_pd3dDevice->ClearRenderTargetView(g_mainRenderTargetView, clear_color_with_alpha);
         ImGui_ImplDX10_RenderDrawData(ImGui::GetDrawData());
 
+        // Update and Render additional Platform Windows
+        if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+        {
+            ImGui::UpdatePlatformWindows();
+            ImGui::RenderPlatformWindowsDefault();
+        }
+
         // Present
         HRESULT hr = g_pSwapChain->Present(1, 0);   // Present with vsync
         //HRESULT hr = g_pSwapChain->Present(0, 0); // Present without vsync
@@ -186,7 +205,6 @@ int main(int, char**)
 }
 
 // Helper functions
-
 bool CreateDeviceD3D(HWND hWnd)
 {
     // Setup swap chain

examples/example_win32_directx11/main.cpp

@@ -54,11 +54,28 @@ int main(int, char**)
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
+    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;       // Enable Multi-Viewport / Platform Windows
+    //io.ConfigViewportsNoAutoMerge = true;
+    //io.ConfigViewportsNoTaskBarIcon = true;
+    //io.ConfigViewportsNoDefaultParent = true;
+    //io.ConfigDockingAlwaysTabBar = true;
+    //io.ConfigDockingTransparentPayload = true;
+    //io.ConfigFlags |= ImGuiConfigFlags_DpiEnableScaleFonts;     // FIXME-DPI: Experimental. THIS CURRENTLY DOESN'T WORK AS EXPECTED. DON'T USE IN USER APP!
+    //io.ConfigFlags |= ImGuiConfigFlags_DpiEnableScaleViewports; // FIXME-DPI: Experimental.
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsLight();
 
+    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
+    ImGuiStyle& style = ImGui::GetStyle();
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        style.WindowRounding = 0.0f;
+        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
+    }
+
     // Setup Platform/Renderer backends
     ImGui_ImplWin32_Init(hwnd);
     ImGui_ImplDX11_Init(g_pd3dDevice, g_pd3dDeviceContext);
@@ -167,6 +184,13 @@ int main(int, char**)
         g_pd3dDeviceContext->ClearRenderTargetView(g_mainRenderTargetView, clear_color_with_alpha);
         ImGui_ImplDX11_RenderDrawData(ImGui::GetDrawData());
 
+        // Update and Render additional Platform Windows
+        if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+        {
+            ImGui::UpdatePlatformWindows();
+            ImGui::RenderPlatformWindowsDefault();
+        }
+
         // Present
         HRESULT hr = g_pSwapChain->Present(1, 0);   // Present with vsync
         //HRESULT hr = g_pSwapChain->Present(0, 0); // Present without vsync
@@ -186,7 +210,6 @@ int main(int, char**)
 }
 
 // Helper functions
-
 bool CreateDeviceD3D(HWND hWnd)
 {
     // Setup swap chain
@@ -241,6 +264,10 @@ void CleanupRenderTarget()
     if (g_mainRenderTargetView) { g_mainRenderTargetView->Release(); g_mainRenderTargetView = nullptr; }
 }
 
+#ifndef WM_DPICHANGED
+#define WM_DPICHANGED 0x02E0 // From Windows SDK 8.1+ headers
+#endif
+
 // Forward declare message handler from imgui_impl_win32.cpp
 extern IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam);
 
@@ -269,6 +296,15 @@ LRESULT WINAPI WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)
     case WM_DESTROY:
         ::PostQuitMessage(0);
         return 0;
+    case WM_DPICHANGED:
+        if (ImGui::GetIO().ConfigFlags & ImGuiConfigFlags_DpiEnableScaleViewports)
+        {
+            //const int dpi = HIWORD(wParam);
+            //printf("WM_DPICHANGED to %d (%.0f%%)\n", dpi, (float)dpi / 96.0f * 100.0f);
+            const RECT* suggested_rect = (RECT*)lParam;
+            ::SetWindowPos(hWnd, nullptr, suggested_rect->left, suggested_rect->top, suggested_rect->right - suggested_rect->left, suggested_rect->bottom - suggested_rect->top, SWP_NOZORDER | SWP_NOACTIVATE);
+        }
+        break;
     }
     return ::DefWindowProcW(hWnd, msg, wParam, lParam);
 }

examples/example_win32_directx12/build_win32.bat

@@ -1,9 +1,8 @@
 @REM Build for Visual Studio compiler. Run your copy of vcvars32.bat or vcvarsall.bat to setup command-line compiler.
-@REM Important: to build on 32-bit systems, the DX12 backends needs '#define ImTextureID ImU64', so we pass it here.
 @set OUT_DIR=Debug
 @set OUT_EXE=example_win32_directx12
 @set INCLUDES=/I..\.. /I..\..\backends /I "%WindowsSdkDir%Include\um" /I "%WindowsSdkDir%Include\shared"
 @set SOURCES=main.cpp ..\..\backends\imgui_impl_dx12.cpp ..\..\backends\imgui_impl_win32.cpp ..\..\imgui*.cpp
 @set LIBS=d3d12.lib d3dcompiler.lib dxgi.lib
 mkdir Debug
-cl /nologo /Zi /MD /utf-8 %INCLUDES% /D ImTextureID=ImU64 /D UNICODE /D _UNICODE %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS%
+cl /nologo /Zi /MD /utf-8 %INCLUDES% /D UNICODE /D _UNICODE %SOURCES% /Fe%OUT_DIR%/%OUT_EXE%.exe /Fo%OUT_DIR%/ /link %LIBS%

examples/example_win32_directx12/example_win32_directx12.vcxproj

@@ -21,7 +21,7 @@
   <PropertyGroup Label="Globals">
     <ProjectGuid>{b4cf9797-519d-4afe-a8f4-5141a6b521d3}</ProjectGuid>
     <RootNamespace>example_win32_directx12</RootNamespace>
-    <WindowsTargetPlatformVersion>10.0.18362.0</WindowsTargetPlatformVersion>
+    <WindowsTargetPlatformVersion>10.0.20348.0</WindowsTargetPlatformVersion>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.Default.props" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
@@ -87,7 +87,7 @@
       <WarningLevel>Level4</WarningLevel>
       <Optimization>Disabled</Optimization>
       <AdditionalIncludeDirectories>..\..;..\..\backends;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>ImTextureID=ImU64;_UNICODE;UNICODE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_UNICODE;UNICODE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
     </ClCompile>
     <Link>
@@ -102,7 +102,7 @@
       <WarningLevel>Level4</WarningLevel>
       <Optimization>Disabled</Optimization>
       <AdditionalIncludeDirectories>..\..;..\..\backends;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>ImTextureID=ImU64;_UNICODE;UNICODE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_UNICODE;UNICODE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
     </ClCompile>
     <Link>
@@ -119,7 +119,7 @@
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <AdditionalIncludeDirectories>..\..;..\..\backends;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>ImTextureID=ImU64;_UNICODE;UNICODE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_UNICODE;UNICODE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
     </ClCompile>
     <Link>
@@ -138,7 +138,7 @@
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <AdditionalIncludeDirectories>..\..;..\..\backends;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>ImTextureID=ImU64;_UNICODE;UNICODE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_UNICODE;UNICODE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalOptions>/utf-8 %(AdditionalOptions)</AdditionalOptions>
     </ClCompile>
     <Link>

examples/example_win32_directx12/main.cpp

@@ -6,10 +6,6 @@
 // - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
 // - Introduction, links and more at the top of imgui.cpp
 
-// Important: to compile on 32-bit systems, the DirectX12 backend requires code to be compiled with '#define ImTextureID ImU64'.
-// This is because we need ImTextureID to carry a 64-bit value and by default ImTextureID is defined as void*.
-// This define is set in the example .vcxproj file and need to be replicated in your app or by adding it to your imconfig.h file.
-
 #include "imgui.h"
 #include "imgui_impl_win32.h"
 #include "imgui_impl_dx12.h"
@@ -26,23 +22,70 @@
 #pragma comment(lib, "dxguid.lib")
 #endif
 
-#include "imgui_internal.h"
+// Config for example app
+static const int APP_NUM_FRAMES_IN_FLIGHT = 3;
+static const int APP_NUM_BACK_BUFFERS = 3;
+static const int APP_SRV_HEAP_SIZE = 64;
 
 struct FrameContext
 {
-    ID3D12CommandAllocator* CommandAllocator;
-    UINT64                  FenceValue;
+    ID3D12CommandAllocator*     CommandAllocator;
+    UINT64                      FenceValue;
+};
+
+// Simple free list based allocator
+struct ExampleDescriptorHeapAllocator
+{
+    ID3D12DescriptorHeap*       Heap = nullptr;
+    D3D12_DESCRIPTOR_HEAP_TYPE  HeapType = D3D12_DESCRIPTOR_HEAP_TYPE_NUM_TYPES;
+    D3D12_CPU_DESCRIPTOR_HANDLE HeapStartCpu;
+    D3D12_GPU_DESCRIPTOR_HANDLE HeapStartGpu;
+    UINT                        HeapHandleIncrement;
+    ImVector<int>               FreeIndices;
+
+    void Create(ID3D12Device* device, ID3D12DescriptorHeap* heap)
+    {
+        IM_ASSERT(Heap == nullptr && FreeIndices.empty());
+        Heap = heap;
+        D3D12_DESCRIPTOR_HEAP_DESC desc = heap->GetDesc();
+        HeapType = desc.Type;
+        HeapStartCpu = Heap->GetCPUDescriptorHandleForHeapStart();
+        HeapStartGpu = Heap->GetGPUDescriptorHandleForHeapStart();
+        HeapHandleIncrement = device->GetDescriptorHandleIncrementSize(HeapType);
+        FreeIndices.reserve((int)desc.NumDescriptors);
+        for (int n = desc.NumDescriptors; n > 0; n--)
+            FreeIndices.push_back(n);
+    }
+    void Destroy()
+    {
+        Heap = nullptr;
+        FreeIndices.clear();
+    }
+    void Alloc(D3D12_CPU_DESCRIPTOR_HANDLE* out_cpu_desc_handle, D3D12_GPU_DESCRIPTOR_HANDLE* out_gpu_desc_handle)
+    {
+        IM_ASSERT(FreeIndices.Size > 0);
+        int idx = FreeIndices.back();
+        FreeIndices.pop_back();
+        out_cpu_desc_handle->ptr = HeapStartCpu.ptr + (idx * HeapHandleIncrement);
+        out_gpu_desc_handle->ptr = HeapStartGpu.ptr + (idx * HeapHandleIncrement);
+    }
+    void Free(D3D12_CPU_DESCRIPTOR_HANDLE out_cpu_desc_handle, D3D12_GPU_DESCRIPTOR_HANDLE out_gpu_desc_handle)
+    {
+        int cpu_idx = (int)((out_cpu_desc_handle.ptr - HeapStartCpu.ptr) / HeapHandleIncrement);
+        int gpu_idx = (int)((out_gpu_desc_handle.ptr - HeapStartGpu.ptr) / HeapHandleIncrement);
+        IM_ASSERT(cpu_idx == gpu_idx);
+        FreeIndices.push_back(cpu_idx);
+    }
 };
 
 // Data
-static int const                    NUM_FRAMES_IN_FLIGHT = 3;
-static FrameContext                 g_frameContext[NUM_FRAMES_IN_FLIGHT] = {};
+static FrameContext                 g_frameContext[APP_NUM_FRAMES_IN_FLIGHT] = {};
 static UINT                         g_frameIndex = 0;
 
-static int const                    NUM_BACK_BUFFERS = 3;
 static ID3D12Device*                g_pd3dDevice = nullptr;
 static ID3D12DescriptorHeap*        g_pd3dRtvDescHeap = nullptr;
 static ID3D12DescriptorHeap*        g_pd3dSrvDescHeap = nullptr;
+static ExampleDescriptorHeapAllocator g_pd3dSrvDescHeapAlloc;
 static ID3D12CommandQueue*          g_pd3dCommandQueue = nullptr;
 static ID3D12GraphicsCommandList*   g_pd3dCommandList = nullptr;
 static ID3D12Fence*                 g_fence = nullptr;
@@ -51,8 +94,8 @@ static UINT64                       g_fenceLastSignaledValue = 0;
 static IDXGISwapChain3*             g_pSwapChain = nullptr;
 static bool                         g_SwapChainOccluded = false;
 static HANDLE                       g_hSwapChainWaitableObject = nullptr;
-static ID3D12Resource*              g_mainRenderTargetResource[NUM_BACK_BUFFERS] = {};
-static D3D12_CPU_DESCRIPTOR_HANDLE  g_mainRenderTargetDescriptor[NUM_BACK_BUFFERS] = {};
+static ID3D12Resource*              g_mainRenderTargetResource[APP_NUM_BACK_BUFFERS] = {};
+static D3D12_CPU_DESCRIPTOR_HANDLE  g_mainRenderTargetDescriptor[APP_NUM_BACK_BUFFERS] = {};
 
 // Forward declarations of helper functions
 bool CreateDeviceD3D(HWND hWnd);
@@ -90,17 +133,38 @@ int main(int, char**)
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
+    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;       // Enable Multi-Viewport / Platform Windows
+    //io.ConfigViewportsNoAutoMerge = true;
+    //io.ConfigViewportsNoTaskBarIcon = true;
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsLight();
 
+    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
+    ImGuiStyle& style = ImGui::GetStyle();
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        style.WindowRounding = 0.0f;
+        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
+    }
+
     // Setup Platform/Renderer backends
     ImGui_ImplWin32_Init(hwnd);
-    ImGui_ImplDX12_Init(g_pd3dDevice, NUM_FRAMES_IN_FLIGHT,
-        DXGI_FORMAT_R8G8B8A8_UNORM, g_pd3dSrvDescHeap,
-        g_pd3dSrvDescHeap->GetCPUDescriptorHandleForHeapStart(),
-        g_pd3dSrvDescHeap->GetGPUDescriptorHandleForHeapStart());
+
+    ImGui_ImplDX12_InitInfo init_info = {};
+    init_info.Device = g_pd3dDevice;
+    init_info.CommandQueue = g_pd3dCommandQueue;
+    init_info.NumFramesInFlight = APP_NUM_FRAMES_IN_FLIGHT;
+    init_info.RTVFormat = DXGI_FORMAT_R8G8B8A8_UNORM;
+    init_info.DSVFormat = DXGI_FORMAT_UNKNOWN;
+    // Allocating SRV descriptors (for textures) is up to the application, so we provide callbacks.
+    // (current version of the backend will only allocate one descriptor, future versions will need to allocate more)
+    init_info.SrvDescriptorHeap = g_pd3dSrvDescHeap;
+    init_info.SrvDescriptorAllocFn = [](ImGui_ImplDX12_InitInfo*, D3D12_CPU_DESCRIPTOR_HANDLE* out_cpu_handle, D3D12_GPU_DESCRIPTOR_HANDLE* out_gpu_handle) { return g_pd3dSrvDescHeapAlloc.Alloc(out_cpu_handle, out_gpu_handle); };
+    init_info.SrvDescriptorFreeFn = [](ImGui_ImplDX12_InitInfo*, D3D12_CPU_DESCRIPTOR_HANDLE cpu_handle, D3D12_GPU_DESCRIPTOR_HANDLE gpu_handle)            { return g_pd3dSrvDescHeapAlloc.Free(cpu_handle, gpu_handle); };
+    ImGui_ImplDX12_Init(&init_info);
 
     // Load Fonts
     // - If no fonts are loaded, dear imgui will use the default font. You can also load multiple fonts and use ImGui::PushFont()/PopFont() to select them.
@@ -220,6 +284,13 @@ int main(int, char**)
 
         g_pd3dCommandQueue->ExecuteCommandLists(1, (ID3D12CommandList* const*)&g_pd3dCommandList);
 
+        // Update and Render additional Platform Windows
+        if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+        {
+            ImGui::UpdatePlatformWindows();
+            ImGui::RenderPlatformWindowsDefault();
+        }
+
         // Present
         HRESULT hr = g_pSwapChain->Present(1, 0);   // Present with vsync
         //HRESULT hr = g_pSwapChain->Present(0, 0); // Present without vsync
@@ -246,14 +317,13 @@ int main(int, char**)
 }
 
 // Helper functions
-
 bool CreateDeviceD3D(HWND hWnd)
 {
     // Setup swap chain
     DXGI_SWAP_CHAIN_DESC1 sd;
     {
         ZeroMemory(&sd, sizeof(sd));
-        sd.BufferCount = NUM_BACK_BUFFERS;
+        sd.BufferCount = APP_NUM_BACK_BUFFERS;
         sd.Width = 0;
         sd.Height = 0;
         sd.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
@@ -296,7 +366,7 @@ bool CreateDeviceD3D(HWND hWnd)
     {
         D3D12_DESCRIPTOR_HEAP_DESC desc = {};
         desc.Type = D3D12_DESCRIPTOR_HEAP_TYPE_RTV;
-        desc.NumDescriptors = NUM_BACK_BUFFERS;
+        desc.NumDescriptors = APP_NUM_BACK_BUFFERS;
         desc.Flags = D3D12_DESCRIPTOR_HEAP_FLAG_NONE;
         desc.NodeMask = 1;
         if (g_pd3dDevice->CreateDescriptorHeap(&desc, IID_PPV_ARGS(&g_pd3dRtvDescHeap)) != S_OK)
@@ -304,7 +374,7 @@ bool CreateDeviceD3D(HWND hWnd)
 
         SIZE_T rtvDescriptorSize = g_pd3dDevice->GetDescriptorHandleIncrementSize(D3D12_DESCRIPTOR_HEAP_TYPE_RTV);
         D3D12_CPU_DESCRIPTOR_HANDLE rtvHandle = g_pd3dRtvDescHeap->GetCPUDescriptorHandleForHeapStart();
-        for (UINT i = 0; i < NUM_BACK_BUFFERS; i++)
+        for (UINT i = 0; i < APP_NUM_BACK_BUFFERS; i++)
         {
             g_mainRenderTargetDescriptor[i] = rtvHandle;
             rtvHandle.ptr += rtvDescriptorSize;
@@ -314,10 +384,11 @@ bool CreateDeviceD3D(HWND hWnd)
     {
         D3D12_DESCRIPTOR_HEAP_DESC desc = {};
         desc.Type = D3D12_DESCRIPTOR_HEAP_TYPE_CBV_SRV_UAV;
-        desc.NumDescriptors = 1;
+        desc.NumDescriptors = APP_SRV_HEAP_SIZE;
         desc.Flags = D3D12_DESCRIPTOR_HEAP_FLAG_SHADER_VISIBLE;
         if (g_pd3dDevice->CreateDescriptorHeap(&desc, IID_PPV_ARGS(&g_pd3dSrvDescHeap)) != S_OK)
             return false;
+        g_pd3dSrvDescHeapAlloc.Create(g_pd3dDevice, g_pd3dSrvDescHeap);
     }
 
     {
@@ -329,7 +400,7 @@ bool CreateDeviceD3D(HWND hWnd)
             return false;
     }
 
-    for (UINT i = 0; i < NUM_FRAMES_IN_FLIGHT; i++)
+    for (UINT i = 0; i < APP_NUM_FRAMES_IN_FLIGHT; i++)
         if (g_pd3dDevice->CreateCommandAllocator(D3D12_COMMAND_LIST_TYPE_DIRECT, IID_PPV_ARGS(&g_frameContext[i].CommandAllocator)) != S_OK)
             return false;
 
@@ -355,7 +426,7 @@ bool CreateDeviceD3D(HWND hWnd)
             return false;
         swapChain1->Release();
         dxgiFactory->Release();
-        g_pSwapChain->SetMaximumFrameLatency(NUM_BACK_BUFFERS);
+        g_pSwapChain->SetMaximumFrameLatency(APP_NUM_BACK_BUFFERS);
         g_hSwapChainWaitableObject = g_pSwapChain->GetFrameLatencyWaitableObject();
     }
 
@@ -368,7 +439,7 @@ void CleanupDeviceD3D()
     CleanupRenderTarget();
     if (g_pSwapChain) { g_pSwapChain->SetFullscreenState(false, nullptr); g_pSwapChain->Release(); g_pSwapChain = nullptr; }
     if (g_hSwapChainWaitableObject != nullptr) { CloseHandle(g_hSwapChainWaitableObject); }
-    for (UINT i = 0; i < NUM_FRAMES_IN_FLIGHT; i++)
+    for (UINT i = 0; i < APP_NUM_FRAMES_IN_FLIGHT; i++)
         if (g_frameContext[i].CommandAllocator) { g_frameContext[i].CommandAllocator->Release(); g_frameContext[i].CommandAllocator = nullptr; }
     if (g_pd3dCommandQueue) { g_pd3dCommandQueue->Release(); g_pd3dCommandQueue = nullptr; }
     if (g_pd3dCommandList) { g_pd3dCommandList->Release(); g_pd3dCommandList = nullptr; }
@@ -390,7 +461,7 @@ void CleanupDeviceD3D()
 
 void CreateRenderTarget()
 {
-    for (UINT i = 0; i < NUM_BACK_BUFFERS; i++)
+    for (UINT i = 0; i < APP_NUM_BACK_BUFFERS; i++)
     {
         ID3D12Resource* pBackBuffer = nullptr;
         g_pSwapChain->GetBuffer(i, IID_PPV_ARGS(&pBackBuffer));
@@ -403,13 +474,13 @@ void CleanupRenderTarget()
 {
     WaitForLastSubmittedFrame();
 
-    for (UINT i = 0; i < NUM_BACK_BUFFERS; i++)
+    for (UINT i = 0; i < APP_NUM_BACK_BUFFERS; i++)
         if (g_mainRenderTargetResource[i]) { g_mainRenderTargetResource[i]->Release(); g_mainRenderTargetResource[i] = nullptr; }
 }
 
 void WaitForLastSubmittedFrame()
 {
-    FrameContext* frameCtx = &g_frameContext[g_frameIndex % NUM_FRAMES_IN_FLIGHT];
+    FrameContext* frameCtx = &g_frameContext[g_frameIndex % APP_NUM_FRAMES_IN_FLIGHT];
 
     UINT64 fenceValue = frameCtx->FenceValue;
     if (fenceValue == 0)
@@ -431,7 +502,7 @@ FrameContext* WaitForNextFrameResources()
     HANDLE waitableObjects[] = { g_hSwapChainWaitableObject, nullptr };
     DWORD numWaitableObjects = 1;
 
-    FrameContext* frameCtx = &g_frameContext[nextFrameIndex % NUM_FRAMES_IN_FLIGHT];
+    FrameContext* frameCtx = &g_frameContext[nextFrameIndex % APP_NUM_FRAMES_IN_FLIGHT];
     UINT64 fenceValue = frameCtx->FenceValue;
     if (fenceValue != 0) // means no fence was signaled
     {

examples/example_win32_directx9/main.cpp

@@ -52,11 +52,23 @@ int main(int, char**)
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;     // Enable Keyboard Controls
     io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;      // Enable Gamepad Controls
+    io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;         // Enable Docking
+    io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable;       // Enable Multi-Viewport / Platform Windows
+    //io.ConfigViewportsNoAutoMerge = true;
+    //io.ConfigViewportsNoTaskBarIcon = true;
 
     // Setup Dear ImGui style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsLight();
 
+    // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
+    ImGuiStyle& style = ImGui::GetStyle();
+    if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+    {
+        style.WindowRounding = 0.0f;
+        style.Colors[ImGuiCol_WindowBg].w = 1.0f;
+    }
+
     // Setup Platform/Renderer backends
     ImGui_ImplWin32_Init(hwnd);
     ImGui_ImplDX9_Init(g_pd3dDevice);
@@ -177,6 +189,14 @@ int main(int, char**)
             ImGui_ImplDX9_RenderDrawData(ImGui::GetDrawData());
             g_pd3dDevice->EndScene();
         }
+
+        // Update and Render additional Platform Windows
+        if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
+        {
+            ImGui::UpdatePlatformWindows();
+            ImGui::RenderPlatformWindowsDefault();
+        }
+
         HRESULT result = g_pd3dDevice->Present(nullptr, nullptr, nullptr, nullptr);
         if (result == D3DERR_DEVICELOST)
             g_DeviceLost = true;
@@ -195,7 +215,6 @@ int main(int, char**)
 }
 
 // Helper functions
-
 bool CreateDeviceD3D(HWND hWnd)
 {
     if ((g_pD3D = Direct3DCreate9(D3D_SDK_VERSION)) == nullptr)
@@ -231,6 +250,10 @@ void ResetDevice()
     ImGui_ImplDX9_CreateDeviceObjects();
 }
 
+#ifndef WM_DPICHANGED
+#define WM_DPICHANGED 0x02E0 // From Windows SDK 8.1+ headers
+#endif
+
 // Forward declare message handler from imgui_impl_win32.cpp
 extern IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam);
 
@@ -259,6 +282,15 @@ LRESULT WINAPI WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)
     case WM_DESTROY:
         ::PostQuitMessage(0);
         return 0;
+    case WM_DPICHANGED:
+        if (ImGui::GetIO().ConfigFlags & ImGuiConfigFlags_DpiEnableScaleViewports)
+        {
+            //const int dpi = HIWORD(wParam);
+            //printf("WM_DPICHANGED to %d (%.0f%%)\n", dpi, (float)dpi / 96.0f * 100.0f);
+            const RECT* suggested_rect = (RECT*)lParam;
+            ::SetWindowPos(hWnd, nullptr, suggested_rect->left, suggested_rect->top, suggested_rect->right - suggested_rect->left, suggested_rect->bottom - suggested_rect->top, SWP_NOZORDER | SWP_NOACTIVATE);
+        }
+        break;
     }
     return ::DefWindowProcW(hWnd, msg, wParam, lParam);
 }

examples/example_win32_opengl3/build_mingw.bat

@@ -0,0 +1,8 @@
+@REM Build for MINGW64 or 32 from MSYS2. 
+@set OUT_DIR=Debug
+@set OUT_EXE=example_win32_opengl3
+@set INCLUDES=-I../.. -I../../backends
+@set SOURCES=main.cpp ../../backends/imgui_impl_opengl3.cpp ../../backends/imgui_impl_win32.cpp ../../imgui*.cpp
+@set LIBS=-lopengl32 -lgdi32 -ldwmapi
+mkdir %OUT_DIR%
+g++ -DUNICODE %INCLUDES% %SOURCES% -o %OUT_DIR%/%OUT_EXE%.exe --static -mwindows %LIBS% %LIBS%