Examples: Win32+DX9/DX10/DX11/DX12, SDL2+DX11/OpenGL2/OpenGL3/SDLRenderer/Vulkan, SDL3+OpenGL/SDLGPU/SDLRenderer/Vulkan: made example DPI aware by default. (master + docking: partial support for multi-dpi by scaling fonts + viewports but not style)

We don't bother with WIN32_LEAN_AND_MEAN.

# Conflicts:
#	examples/example_glfw_opengl3/main.cpp
#	examples/example_sdl2_directx11/main.cpp
#	examples/example_sdl2_opengl2/main.cpp
#	examples/example_sdl2_opengl3/main.cpp
#	examples/example_sdl2_vulkan/main.cpp
#	examples/example_sdl3_opengl3/main.cpp
#	examples/example_sdl3_sdlgpu3/main.cpp
#	examples/example_sdl3_vulkan/main.cpp
#	examples/example_win32_directx10/main.cpp
#	examples/example_win32_directx11/main.cpp
#	examples/example_win32_directx12/main.cpp
#	examples/example_win32_directx9/main.cpp

examples/example_glfw_opengl3/main.cpp

@@ -71,7 +71,8 @@ int main(int, char**)
 #endif
 
     // Create window with graphics context
-    GLFWwindow* window = glfwCreateWindow(1280, 720, "Dear ImGui GLFW+OpenGL3 example", nullptr, nullptr);
+    float main_scale = ImGui_ImplGlfw_GetContentScaleForMonitor(glfwGetPrimaryMonitor()); // Valid on GLFW 3.3+ only
+    GLFWwindow* window = glfwCreateWindow((int)(1280 * main_scale), (int)(800 * main_scale), "Dear ImGui GLFW+OpenGL3 example", nullptr, nullptr);
     if (window == nullptr)
         return 1;
     glfwMakeContextCurrent(window);
@@ -88,6 +89,11 @@ int main(int, char**)
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsLight();
 
+    // Setup scaling
+    ImGuiStyle& style = ImGui::GetStyle();
+    style.ScaleAllSizes(main_scale);        // Bake a fixed style scale. (until we have a solution for dynamic style scaling, changing this requires resetting Style + calling this again)
+    style.FontScaleDpi = main_scale;        // Set initial font scale. (using io.ConfigDpiScaleFonts=true makes this unnecessary. We leave both here for documentation purpose)
+
     // Setup Platform/Renderer backends
     ImGui_ImplGlfw_InitForOpenGL(window, true);
 #ifdef __EMSCRIPTEN__