Examples: Misc comments mainly related to GLFW callbacks. (#1759)

examples/example_allegro5/main.cpp

@@ -22,14 +22,16 @@ int main(int, char**)
     al_register_event_source(queue, al_get_keyboard_event_source());
     al_register_event_source(queue, al_get_mouse_event_source());
 
-    // Setup Dear ImGui binding
+    // Setup Dear ImGui context
     IMGUI_CHECKVERSION();
     ImGui::CreateContext();
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     //io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;  // Enable Keyboard Controls
+
+    // Setup Platform/Renderer bindings
     ImGui_ImplAllegro5_Init(display);
 
-    // Setup style
+    // Setup Style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsClassic();
 

examples/example_apple_opengl2/main.mm

@@ -237,16 +237,17 @@
     if ([view openGLContext] == nil)
         NSLog(@"No OpenGL Context!");
 
-    // Setup Dear ImGui binding
+    // Setup Dear ImGui context
     IMGUI_CHECKVERSION();
     ImGui::CreateContext();
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     //io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;  // Enable Keyboard Controls
 
+    // Setup Platform/Renderer bindings
     ImGui_ImplOSX_Init();
     ImGui_ImplOpenGL2_Init();
 
-    // Setup style
+    // Setup Style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsClassic();
 

examples/example_freeglut_opengl2/main.cpp

@@ -95,16 +95,17 @@ int main(int argc, char** argv)
     // otherwise it is possible to install our own functions and call the imgui_impl_freeglut.h functions ourselves.
     glutDisplayFunc(glut_display_func);
 
-    // Setup Dear ImGui binding
+    // Setup Dear ImGui context
     ImGui::CreateContext();
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     //io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;  // Enable Keyboard Controls
 
+    // Setup Platform/Renderer bindings
     ImGui_ImplFreeGLUT_Init();
     ImGui_ImplFreeGLUT_InstallFuncs();
     ImGui_ImplOpenGL2_Init();
 
-    // Setup style
+    // Setup Style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsClassic();
 

examples/example_glfw_opengl2/main.cpp

@@ -36,17 +36,19 @@ int main(int, char**)
     glfwMakeContextCurrent(window);
     glfwSwapInterval(1); // Enable vsync
 
-    // Setup Dear ImGui binding
+    // 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
 
+    // Setup Platform/Renderer bindings
+    // If you have already installed GLFW callbacks in your app, call ImGui_ImplGlfw_InitForOpenGL() with install_callbacks=false and call them yourself.
     ImGui_ImplGlfw_InitForOpenGL(window, true);
     ImGui_ImplOpenGL2_Init();
 
-    // Setup style
+    // Setup Style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsClassic();
 

examples/example_glfw_opengl3/main.cpp

@@ -82,17 +82,19 @@ int main(int, char**)
         return 1;
     }
 
-    // Setup Dear ImGui binding
+    // 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
 
+    // Setup Platform/Renderer bindings
+    // If you have already installed GLFW callbacks in your app, call ImGui_ImplGlfw_InitForOpenGL() with install_callbacks=false and call them yourself.
     ImGui_ImplGlfw_InitForOpenGL(window, true);
     ImGui_ImplOpenGL3_Init(glsl_version);
 
-    // Setup style
+    // Setup Style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsClassic();
 

examples/example_glfw_vulkan/main.cpp

@@ -350,17 +350,16 @@ int main(int, char**)
     ImGui_ImplVulkanH_WindowData* wd = &g_WindowData;
     SetupVulkanWindowData(wd, surface, w, h);
 
-    // Setup Dear ImGui binding
+    // 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
 
-    // Setup GLFW binding
+    // Setup Platform/Renderer bindings
+    // If you have already installed GLFW callbacks in your app, call ImGui_ImplGlfw_InitForVulkan() with install_callbacks=false and call the functions yourself.
     ImGui_ImplGlfw_InitForVulkan(window, true);
-
-    // Setup Vulkan binding
     ImGui_ImplVulkan_InitInfo init_info = {};
     init_info.Instance = g_Instance;
     init_info.PhysicalDevice = g_PhysicalDevice;
@@ -373,7 +372,7 @@ int main(int, char**)
     init_info.CheckVkResultFn = check_vk_result;
     ImGui_ImplVulkan_Init(&init_info, wd->RenderPass);
 
-    // Setup style
+    // Setup Style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsClassic();
 

examples/example_marmalade/main.cpp

@@ -16,14 +16,16 @@ int main(int, char**)
 {
     IwGxInit();
 
-    // Setup Dear ImGui binding
+    // Setup Dear ImGui context
     IMGUI_CHECKVERSION();
     ImGui::CreateContext();
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     //io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;  // Enable Keyboard Controls
+
+    // Setup Platform/Renderer bindings
     ImGui_Marmalade_Init(true);
 
-    // Setup style
+    // Setup Style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsClassic();
 

examples/example_sdl_opengl2/main.cpp

@@ -34,16 +34,17 @@ int main(int, char**)
     SDL_GLContext gl_context = SDL_GL_CreateContext(window);
     SDL_GL_SetSwapInterval(1); // Enable vsync
 
-    // Setup Dear ImGui binding
+    // Setup Dear ImGui context
     IMGUI_CHECKVERSION();
     ImGui::CreateContext();
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     //io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;  // Enable Keyboard Controls
 
+    // Setup Platform/Renderer bindings
     ImGui_ImplSDL2_InitForOpenGL(window, gl_context);
     ImGui_ImplOpenGL2_Init();
 
-    // Setup style
+    // Setup Style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsClassic();
 

examples/example_sdl_opengl3/main.cpp

@@ -74,16 +74,17 @@ int main(int, char**)
         return 1;
     }
 
-    // Setup Dear ImGui binding
+    // Setup Dear ImGui context
     IMGUI_CHECKVERSION();
     ImGui::CreateContext();
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     //io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;  // Enable Keyboard Controls
 
+    // Setup Platform/Renderer bindings
     ImGui_ImplSDL2_InitForOpenGL(window, gl_context);
     ImGui_ImplOpenGL3_Init(glsl_version);
 
-    // Setup style
+    // Setup Style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsClassic();
 

examples/example_sdl_vulkan/main.cpp

@@ -333,15 +333,13 @@ int main(int, char**)
     ImGui_ImplVulkanH_WindowData* wd = &g_WindowData;
     SetupVulkanWindowData(wd, surface, w, h);
 
-    // Setup Dear ImGui binding
+    // Setup Dear ImGui context
     ImGui::CreateContext();
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     //io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;  // Enable Keyboard Controls
 
-    // Setup SDL binding
+    // Setup Platform/Renderer bindings
     ImGui_ImplSDL2_InitForVulkan(window);
-
-    // Setup Vulkan binding
     ImGui_ImplVulkan_InitInfo init_info = {};
     init_info.Instance = g_Instance;
     init_info.PhysicalDevice = g_PhysicalDevice;
@@ -354,7 +352,7 @@ int main(int, char**)
     init_info.CheckVkResultFn = check_vk_result;
     ImGui_ImplVulkan_Init(&init_info, wd->RenderPass);
 
-    // Setup style
+    // Setup Style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsClassic();
 

examples/example_win32_directx10/main.cpp

@@ -110,16 +110,17 @@ int main(int, char**)
     ShowWindow(hwnd, SW_SHOWDEFAULT);
     UpdateWindow(hwnd);
 
-    // Setup Dear ImGui binding
+    // Setup Dear ImGui context
     IMGUI_CHECKVERSION();
     ImGui::CreateContext();
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     //io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;  // Enable Keyboard Controls
 
+    // Setup Platform/Renderer bindings
     ImGui_ImplWin32_Init(hwnd);
     ImGui_ImplDX10_Init(g_pd3dDevice);
 
-    // Setup style
+    // Setup Style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsClassic();
 

examples/example_win32_directx11/main.cpp

@@ -113,16 +113,17 @@ int main(int, char**)
     ShowWindow(hwnd, SW_SHOWDEFAULT);
     UpdateWindow(hwnd);
 
-    // Setup Dear ImGui binding
+    // Setup Dear ImGui context
     IMGUI_CHECKVERSION();
     ImGui::CreateContext();
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     //io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;  // Enable Keyboard Controls
 
+    // Setup Platform/Renderer bindings
     ImGui_ImplWin32_Init(hwnd);
     ImGui_ImplDX11_Init(g_pd3dDevice, g_pd3dDeviceContext);
 
-    // Setup style
+    // Setup Style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsClassic();
 

examples/example_win32_directx12/main.cpp

@@ -286,19 +286,20 @@ int main(int, char**)
     ShowWindow(hwnd, SW_SHOWDEFAULT);
     UpdateWindow(hwnd);
 
-    // Setup Dear ImGui binding
+    // Setup Dear ImGui context
     IMGUI_CHECKVERSION();
     ImGui::CreateContext();
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     //io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;  // Enable Keyboard Controls
 
+    // Setup Platform/Renderer bindings
     ImGui_ImplWin32_Init(hwnd);
     ImGui_ImplDX12_Init(g_pd3dDevice, NUM_FRAMES_IN_FLIGHT, 
         DXGI_FORMAT_R8G8B8A8_UNORM,
         g_pd3dSrvDescHeap->GetCPUDescriptorHandleForHeapStart(), 
         g_pd3dSrvDescHeap->GetGPUDescriptorHandleForHeapStart());
 
-    // Setup style
+    // Setup Style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsClassic();
 

examples/example_win32_directx9/main.cpp

@@ -75,15 +75,17 @@ int main(int, char**)
         return 0;
     }
 
-    // Setup Dear ImGui binding
+    // Setup Dear ImGui context
     IMGUI_CHECKVERSION();
     ImGui::CreateContext();
     ImGuiIO& io = ImGui::GetIO(); (void)io;
     //io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;  // Enable Keyboard Controls
+
+    // Setup Platform/Renderer bindings
     ImGui_ImplWin32_Init(hwnd);
     ImGui_ImplDX9_Init(g_pd3dDevice);
 
-    // Setup style
+    // Setup Style
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsClassic();
 

examples/imgui_impl_glfw.cpp

@@ -102,14 +102,6 @@ void ImGui_ImplGlfw_CharCallback(GLFWwindow*, unsigned int c)
         io.AddInputCharacter((unsigned short)c);
 }
 
-void ImGui_ImplGlfw_InstallCallbacks(GLFWwindow* window)
-{
-    glfwSetMouseButtonCallback(window, ImGui_ImplGlfw_MouseButtonCallback);
-    glfwSetScrollCallback(window, ImGui_ImplGlfw_ScrollCallback);
-    glfwSetKeyCallback(window, ImGui_ImplGlfw_KeyCallback);
-    glfwSetCharCallback(window, ImGui_ImplGlfw_CharCallback);
-}
-
 static bool ImGui_ImplGlfw_Init(GLFWwindow* window, bool install_callbacks, GlfwClientApi client_api)
 {
     g_Window = window;
@@ -160,7 +152,12 @@ static bool ImGui_ImplGlfw_Init(GLFWwindow* window, bool install_callbacks, Glfw
     g_MouseCursors[ImGuiMouseCursor_Hand] = glfwCreateStandardCursor(GLFW_HAND_CURSOR);
     
     if (install_callbacks)
-        ImGui_ImplGlfw_InstallCallbacks(window);
+    {
+        glfwSetMouseButtonCallback(window, ImGui_ImplGlfw_MouseButtonCallback);
+        glfwSetScrollCallback(window, ImGui_ImplGlfw_ScrollCallback);
+        glfwSetKeyCallback(window, ImGui_ImplGlfw_KeyCallback);
+        glfwSetCharCallback(window, ImGui_ImplGlfw_CharCallback);
+    }
 
     g_ClientApi = client_api;
     return true;

examples/imgui_impl_glfw.h

@@ -25,9 +25,10 @@ IMGUI_IMPL_API bool     ImGui_ImplGlfw_InitForVulkan(GLFWwindow* window, bool in
 IMGUI_IMPL_API void     ImGui_ImplGlfw_Shutdown();
 IMGUI_IMPL_API void     ImGui_ImplGlfw_NewFrame();
 
-// GLFW callbacks (installed by default if you enable 'install_callbacks' during initialization)
+// GLFW callbacks are installed by default if you call the InitXXX function with 'install_callbacks=true'.
-// Provided here if you want to chain callbacks.
+// If you already have GLFW callbacks installed by your application, call the InitXXX function with install_callbacks=false,
-// You can also handle inputs yourself and use those as a reference.
+// then call the functions yourselves from your own GLFW callbacks. 
+// You may also handle inputs yourself and use those as a reference.
 IMGUI_IMPL_API void     ImGui_ImplGlfw_MouseButtonCallback(GLFWwindow* window, int button, int action, int mods);
 IMGUI_IMPL_API void     ImGui_ImplGlfw_ScrollCallback(GLFWwindow* window, double xoffset, double yoffset);
 IMGUI_IMPL_API void     ImGui_ImplGlfw_KeyCallback(GLFWwindow* window, int key, int scancode, int action, int mods);