Backends: Metal4: added metal-cpp support. (#9461)

with amends.

backends/imgui_impl_metal.mm

@@ -123,7 +123,6 @@ void ImGui_ImplMetal_RenderDrawData(ImDrawData* draw_data,
     ImGui_ImplMetal_RenderDrawData(draw_data,
                                    (__bridge id<MTLCommandBuffer>)(commandBuffer),
                                    (__bridge id<MTLRenderCommandEncoder>)(commandEncoder));
-
 }
 
 bool ImGui_ImplMetal_CreateDeviceObjects(MTL::Device* device)

backends/imgui_impl_metal4.h

@@ -7,7 +7,6 @@
 //  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
 //  [X] Renderer: Texture updates support for dynamic font atlas (ImGuiBackendFlags_RendererHasTextures).
 // Missing features or Issues:
-//  [ ] Metal-cpp support.
 //  [ ] Texture view pool support? Reevaluate which type to use for ImtextureID.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
@@ -53,6 +52,38 @@ IMGUI_IMPL_API void ImGui_ImplMetal4_UpdateTexture(ImTextureData* tex);
 
 #endif
 
+//-----------------------------------------------------------------------------
+// C++ API
+//-----------------------------------------------------------------------------
+
+// Enable Metal C++ binding support with '#define IMGUI_IMPL_METAL_CPP' in your imconfig.h file
+// More info about using Metal from C++: https://developer.apple.com/metal/cpp/
+
+#ifdef IMGUI_IMPL_METAL_CPP
+#ifndef __OBJC__
+
+// Forward declare relevant classes from the MTL and MTL4 namespace
+namespace MTL { class Device; }
+namespace MTL4 { class CommandQueue; class CommandBuffer; class RenderPassDescriptor; class RenderCommandEncoder; }
+
+// Follow "Getting Started" link and check examples/ folder to learn about using backends!
+IMGUI_IMPL_API bool ImGui_ImplMetal4_Init(MTL::Device* device, MTL4::CommandQueue* commandQueue, int framesInFlight);
+IMGUI_IMPL_API void ImGui_ImplMetal4_Shutdown();
+IMGUI_IMPL_API void ImGui_ImplMetal4_NewFrame(MTL4::RenderPassDescriptor* renderPassDescriptor, int frameInFlightIndex);
+IMGUI_IMPL_API void ImGui_ImplMetal4_RenderDrawData(ImDrawData* draw_data,
+                                                   MTL4::CommandBuffer* commandBuffer,
+                                                   MTL4::RenderCommandEncoder* commandEncoder);
+
+// Called by Init/NewFrame/Shutdown
+IMGUI_IMPL_API bool ImGui_ImplMetal4_CreateDeviceObjects(MTL::Device* device);
+IMGUI_IMPL_API void ImGui_ImplMetal4_DestroyDeviceObjects();
+
+// (Advanced) Use e.g. if you need to precisely control the timing of texture updates (e.g. for staged rendering), by setting ImDrawData::Textures = nullptr to handle this manually.
+IMGUI_IMPL_API void ImGui_ImplMetal4_UpdateTexture(ImTextureData* tex);
+
+#endif
+#endif
+
 //-----------------------------------------------------------------------------
 
 #endif // #ifndef IMGUI_DISABLE

backends/imgui_impl_metal4.mm

@@ -7,7 +7,6 @@
 //  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
 //  [X] Renderer: Texture updates support for dynamic font atlas (ImGuiBackendFlags_RendererHasTextures).
 // Missing features or Issues:
-//  [ ] Metal-cpp support.
 //  [ ] Texture view pool support? Reevaluate which type to use for ImtextureID.
 
 // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
@@ -20,6 +19,7 @@
 
 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
+//  2026-07-07: Metal 4: Added metal-cpp support. (#9461)
 //  2026-07-02: Metal 4: Added new Metal 4 backend implementation. (#9458)
 
 #include "imgui.h"
@@ -28,6 +28,10 @@
 #import <time.h>
 #import <Metal/Metal.h>
 
+#ifdef IMGUI_IMPL_METAL_CPP
+#include <Metal/Metal.hpp>
+#endif
+
 #pragma mark - Support classes and structs
 
 struct ImGui_Metal4_ConstantData
@@ -95,6 +99,36 @@ static void                      ImGui_ImplMetal4_DestroyBackendData(){ IM_DELET
 
 static inline CFTimeInterval    GetMachAbsoluteTimeInSeconds()      { return (CFTimeInterval)(double)(clock_gettime_nsec_np(CLOCK_UPTIME_RAW) / 1e9); }
 
+#ifdef IMGUI_IMPL_METAL_CPP
+
+#pragma mark - Dear ImGui Metal C++ Backend API
+
+bool ImGui_ImplMetal4_Init(MTL::Device* device, MTL4::CommandQueue* commandQueue, int framesInFlight)
+{
+    return ImGui_ImplMetal4_Init((__bridge id<MTLDevice>)(device),(__bridge id<MTL4CommandQueue>)(commandQueue), framesInFlight);
+}
+
+void ImGui_ImplMetal4_NewFrame(MTL4::RenderPassDescriptor* renderPassDescriptor, int frameInFlightIndex)
+{
+    ImGui_ImplMetal4_NewFrame((__bridge MTL4RenderPassDescriptor*)(renderPassDescriptor), frameInFlightIndex);
+}
+
+void ImGui_ImplMetal4_RenderDrawData(ImDrawData* draw_data,
+                                    MTL4::CommandBuffer* commandBuffer,
+                                    MTL4::RenderCommandEncoder* commandEncoder)
+{
+    ImGui_ImplMetal4_RenderDrawData(draw_data,
+                                   (__bridge id<MTL4CommandBuffer>)(commandBuffer),
+                                   (__bridge id<MTL4RenderCommandEncoder>)(commandEncoder));
+}
+
+bool ImGui_ImplMetal_CreateDeviceObjects(MTL::Device* device)
+{
+    return ImGui_ImplMetal4_CreateDeviceObjects((__bridge id<MTLDevice>)(device));
+}
+
+#endif // #ifdef IMGUI_IMPL_METAL_CPP
+
 #pragma mark - Dear ImGui Metal Backend API
 
 void ImGui_ImplMetal4_NewFrame(MTL4RenderPassDescriptor* renderPassDescriptor, int frameInFlightIndex)

docs/CHANGELOG.txt

@@ -148,7 +148,7 @@ Other Changes:
 - Backends:
   - Metal4:
     - Added new Metal 4 backend (forked from Metal 3 backend). (#9458, #9451) [@AmelieHeinrich]
-      Note that Metal-cpp is not yet supported.
+    - Added Metal-cpp support enabled with `IMGUI_IMPL_METAL_CPP` define. (#9461) [@MERL10N]
   - OpenGL3:
     - GLSL version detection assume GLSL 410 when GL context is 4.1.
       Fixes an issue running on macOS with Wine. [#9427, #6577) [@perminovVS]