Backends: SDLGPU3: Added sdl_gpu backend (amends). (#8163, #7998, #7988)

backends/imgui_impl_sdlgpu3.h

@@ -1,4 +1,4 @@
-// dear imgui: Renderer Backend for SDL_Gpu
+// dear imgui: Renderer Backend for SDL_GPU
 // This needs to be used along with the SDL3 Platform Backend
 
 // Implemented features:
@@ -27,7 +27,7 @@
 
 // Initialization data, for ImGui_ImplSDLGPU_Init()
 // - Remember to set ColorTargetFormat to the correct format. If you're rendering to the swapchain, call SDL_GetGPUSwapchainTextureFormat to query the right value
-struct ImGui_ImplSDLGPU_InitInfo
+struct ImGui_ImplSDLGPU3_InitInfo
 {
     SDL_GPUDevice*       GpuDevice          = nullptr;
     SDL_GPUTextureFormat ColorTargetFormat  = SDL_GPU_TEXTUREFORMAT_INVALID;
@@ -35,12 +35,12 @@ struct ImGui_ImplSDLGPU_InitInfo
 };
 
 // Follow "Getting Started" link and check examples/ folder to learn about using backends!
-IMGUI_IMPL_API bool             ImGui_ImplSDLGPU_Init(ImGui_ImplSDLGPU_InitInfo* info);
-IMGUI_IMPL_API void             ImGui_ImplSDLGPU_Shutdown();
-IMGUI_IMPL_API void             ImGui_ImplSDLGPU_NewFrame();
-IMGUI_IMPL_API void             Imgui_ImplSDLGPU_PrepareDrawData(ImDrawData* draw_data, SDL_GPUCommandBuffer* command_buffer);
-IMGUI_IMPL_API void             ImGui_ImplSDLGPU_RenderDrawData(ImDrawData* draw_data, SDL_GPUCommandBuffer* command_buffer, SDL_GPURenderPass* render_pass, SDL_GPUGraphicsPipeline* pipeline = nullptr);
-IMGUI_IMPL_API bool             ImGui_ImplSDLGPU_CreateFontsTexture();
-IMGUI_IMPL_API void             ImGui_ImplSDLGPU_DestroyFontsTexture();
+IMGUI_IMPL_API bool    ImGui_ImplSDLGPU3_Init(ImGui_ImplSDLGPU3_InitInfo* info);
+IMGUI_IMPL_API void    ImGui_ImplSDLGPU3_Shutdown();
+IMGUI_IMPL_API void    ImGui_ImplSDLGPU3_NewFrame();
+IMGUI_IMPL_API void    Imgui_ImplSDLGPU3_PrepareDrawData(ImDrawData* draw_data, SDL_GPUCommandBuffer* command_buffer);
+IMGUI_IMPL_API void    ImGui_ImplSDLGPU3_RenderDrawData(ImDrawData* draw_data, SDL_GPUCommandBuffer* command_buffer, SDL_GPURenderPass* render_pass, SDL_GPUGraphicsPipeline* pipeline = nullptr);
+IMGUI_IMPL_API bool    ImGui_ImplSDLGPU3_CreateFontsTexture();
+IMGUI_IMPL_API void    ImGui_ImplSDLGPU3_DestroyFontsTexture();
 
 #endif // #ifndef IMGUI_DISABLE

backends/sdlgpu3/build_instructions.txt

@@ -1,3 +1,7 @@
+
+Instructions to rebuild imgui_impl_sdlgpu3_shaders.h
+(You don't need to copy this folder if you are using the backend as-is)
+
 1) Compile the raw shader files to SPIRV:
 
     glslc -o vertex.spv -c shader.vert
@@ -33,4 +37,4 @@
     Proceed to step 4
 
 
-4) Either find a way to load the shader bytecode from file, or use a tool like https://notisrac.github.io/FileToCArray/ to convert the file to a uint8_t array
+4) Use a tool like https://notisrac.github.io/FileToCArray/ or misc/fonts/binary_to_compressed_c.cpp in imgui repository to convert the file to a uint8_t array.

backends/sdlgpu3/shader.frag

@@ -3,7 +3,8 @@ layout(location = 0) out vec4 fColor;
 
 layout(set=2, binding=0) uniform sampler2D sTexture;
 
-layout(location = 0) in struct {
+layout(location = 0) in struct
+{
     vec4 Color;
     vec2 UV;
 } In;

backends/sdlgpu3/shader.vert

@@ -3,12 +3,14 @@ layout(location = 0) in vec2 aPos;
 layout(location = 1) in vec2 aUV;
 layout(location = 2) in vec4 aColor;
 
-layout(set=1,binding=0) uniform UBO {
+layout(set=1,binding=0) uniform UBO
+{
     vec2 uScale;
     vec2 uTranslate;
 } ubo;
 
-layout(location = 0) out struct {
+layout(location = 0) out struct
+{
     vec4 Color;
     vec2 UV;
 } Out;

backends/vulkan/build_instructions.txt

@@ -0,0 +1,4 @@
+
+Script to rebuild shaders stored inside imgui_impl_vulkan.h
+(You don't need to copy this folder if you are using the backend as-is)
+

docs/CHANGELOG.txt

@@ -68,6 +68,7 @@ Other changes:
 - Demo: Added label edition to Property Editor demo + fix an ID issue. (#8266) [@moritz-h]
 - Misc: Fixed misc/cpp/imgui_stdlib.h/.cpp not supporting IMGUI_DISABLE. (#8294) [@juur]
 - Misc: Fixed MinGW builds uses UTF-8 friendly _wfopen(). (#8300)
+- Backends: SDL_GPU for SDL3: Added backend for SDL_GPU! (#8163, #7998, #7988) [@DeltaW0x].
 - Backends: Allegro5: Avoid calling al_set_mouse_cursor() repeatedly since it appears
   to leak on on X11 (#8256). [@Helodity]
 - Backends: Metal: Fixed leaks when using metal-cpp. (#8276, #8166) [@selimsandal]

docs/EXAMPLES.md

@@ -139,8 +139,8 @@ This support building with Emscripten and targeting WebGL.<BR>
 Prefer using that if you are using modern GL or WebGL in your application.
 
 [example_sdl2_sdlrenderer2/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl2_sdlrenderer2/) <BR>
-SDL2 (Win32, Mac, Linux, etc.) + SDL_Renderer for SDL2 (most graphics backends are supported underneath) <BR>
-= main.cpp + imgui_impl_sdl2.cpp + imgui_impl_sdlrenderer.cpp <BR>
+SDL2 (Win32, Mac, Linux, etc.) + SDL_Renderer for SDL2 example.<BR>
+= main.cpp + imgui_impl_sdl2.cpp + imgui_impl_sdlrenderer2.cpp <BR>
 This requires SDL 2.0.18+ (released November 2021) <BR>
 
 [example_sdl2_vulkan/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl2_vulkan/) <BR>
@@ -149,6 +149,26 @@ SDL2 (Win32, Mac, Linux, etc.) + Vulkan example. <BR>
 This is quite long and tedious, because: Vulkan. <BR>
 For this example, the main.cpp file exceptionally use helpers function from imgui_impl_vulkan.h/cpp.
 
+[example_sdl3_opengl3/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl3_opengl3/) <BR>
+SDL3 (Win32, Mac, Linux, etc.) + OpenGL3+/ES2/ES3 example. <BR>
+= main.cpp + imgui_impl_sdl3.cpp + imgui_impl_opengl3.cpp <BR>
+This uses more modern GL calls and custom shaders. <BR>
+This support building with Emscripten and targeting WebGL.<BR>
+
+[example_sdl3_sdlgpu3/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl3_sdlgpu3/) <BR>
+SDL3 (Win32, Mac, Linux, etc.) + SDL_GPU for SDL3 example.<BR>
+= main.cpp + imgui_impl_sdl3.cpp + imgui_impl_sdlrenderer3.cpp <BR>
+
+[example_sdl3_sdlrenderer3/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl3_sdlrenderer3/) <BR>
+SDL3 (Win32, Mac, Linux, etc.) + SDL_Renderer for SDL3 example.<BR>
+= main.cpp + imgui_impl_sdl3.cpp + imgui_impl_sdlrenderer3.cpp <BR>
+
+[example_sdl3_vulkan/](https://github.com/ocornut/imgui/blob/master/examples/example_sdl3_vulkan/) <BR>
+SDL3 (Win32, Mac, Linux, etc.) + Vulkan example. <BR>
+= main.cpp + imgui_impl_sdl3.cpp + imgui_impl_vulkan.cpp <BR>
+This is quite long and tedious, because: Vulkan. <BR>
+For this example, the main.cpp file exceptionally use helpers function from imgui_impl_vulkan.h/cpp.
+
 [example_win32_directx9/](https://github.com/ocornut/imgui/blob/master/examples/example_win32_directx9/) <BR>
 DirectX9 example, Windows only. <BR>
 = main.cpp + imgui_impl_win32.cpp + imgui_impl_dx9.cpp

docs/README.md

@@ -123,7 +123,7 @@ On most platforms and when using C++, **you should be able to use a combination
 Integrating Dear ImGui within your custom engine is a matter of 1) wiring mouse/keyboard/gamepad inputs 2) uploading a texture to your GPU/render engine 3) providing a render function that can bind textures and render textured triangles, which is essentially what Backends are doing. The [examples/](https://github.com/ocornut/imgui/tree/master/examples) folder is populated with applications doing just that: setting up a window and using backends. If you follow the [Getting Started](https://github.com/ocornut/imgui/wiki/Getting-Started) guide it should in theory takes you less than an hour to integrate Dear ImGui.  **Make sure to spend time reading the [FAQ](https://www.dearimgui.com/faq), comments, and the examples applications!**
 
 Officially maintained backends/bindings (in repository):
-- Renderers: DirectX9, DirectX10, DirectX11, DirectX12, Metal, OpenGL/ES/ES2, SDL_Renderer, Vulkan, WebGPU.
+- Renderers: DirectX9, DirectX10, DirectX11, DirectX12, Metal, OpenGL/ES/ES2, SDL_GPU, SDL_Renderer2/3, Vulkan, WebGPU.
 - Platforms: GLFW, SDL2/SDL3, Win32, Glut, OSX, Android.
 - Frameworks: Allegro5, Emscripten.
 

examples/example_sdl3_sdlgpu3/main.cpp

@@ -1,4 +1,4 @@
-// Dear ImGui: standalone example application for SDL_Gpu
+// Dear ImGui: standalone example application for SDL3 + SDL_GPU
 
 // Learn about Dear ImGui:
 // - FAQ                  https://dearimgui.com/faq
@@ -17,7 +17,6 @@
 #include <stdlib.h>         // abort
 #include <SDL3/SDL.h>
 
-
 // This example doesn't compile with Emscripten yet! Awaiting SDL3 support.
 #ifdef __EMSCRIPTEN__
 #include "../libs/emscripten/emscripten_mainloop_stub.h"
@@ -34,23 +33,23 @@ int main(int, char**)
     }
 
     // Create SDL window graphics context
-    SDL_Window* window = SDL_CreateWindow("Dear ImGui SDLGpu example", 1280, 720, SDL_WINDOW_RESIZABLE | SDL_WINDOW_HIGH_PIXEL_DENSITY);
+    SDL_Window* window = SDL_CreateWindow("Dear ImGui SDL3+SDL_GPU example", 1280, 720, SDL_WINDOW_RESIZABLE | SDL_WINDOW_HIGH_PIXEL_DENSITY);
     if (window == nullptr)
     {
         printf("Error: SDL_CreateWindow(): %s\n", SDL_GetError());
         return -1;
     }
 
-    // Create SDL Gpu Device
-    SDL_GPUDevice* gpuDevice = SDL_CreateGPUDevice(SDL_GPU_SHADERFORMAT_SPIRV | SDL_GPU_SHADERFORMAT_DXIL | SDL_GPU_SHADERFORMAT_METALLIB,true,nullptr);
-    if (gpuDevice == nullptr)
+    // Create GPU Device
+    SDL_GPUDevice* gpu_device = SDL_CreateGPUDevice(SDL_GPU_SHADERFORMAT_SPIRV | SDL_GPU_SHADERFORMAT_DXIL | SDL_GPU_SHADERFORMAT_METALLIB,true,nullptr);
+    if (gpu_device == nullptr)
     {
         printf("Error: SDL_CreateGPUDevice(): %s\n", SDL_GetError());
         return -1;
     }
 
     // Claim window for GPU Device
-    if (!SDL_ClaimWindowForGPUDevice(gpuDevice, window))
+    if (!SDL_ClaimWindowForGPUDevice(gpu_device, window))
     {
         printf("Error: SDL_ClaimWindowForGPUDevice(): %s\n", SDL_GetError());
         return -1;
@@ -69,11 +68,11 @@ int main(int, char**)
 
     // Setup Platform/Renderer backends
     ImGui_ImplSDL3_InitForOther(window);
-    ImGui_ImplSDLGPU_InitInfo init_info = {};
-    init_info.GpuDevice = gpuDevice;
-    init_info.ColorTargetFormat = SDL_GetGPUSwapchainTextureFormat(gpuDevice, window);
+    ImGui_ImplSDLGPU3_InitInfo init_info = {};
+    init_info.GpuDevice = gpu_device;
+    init_info.ColorTargetFormat = SDL_GetGPUSwapchainTextureFormat(gpu_device, window);
     init_info.MSAASamples = SDL_GPU_SAMPLECOUNT_1;
-    ImGui_ImplSDLGPU_Init(&init_info);
+    ImGui_ImplSDLGPU3_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.
@@ -121,7 +120,7 @@ int main(int, char**)
         }
 
         // Start the Dear ImGui frame
-        ImGui_ImplSDLGPU_NewFrame();
+        ImGui_ImplSDLGPU3_NewFrame();
         ImGui_ImplSDL3_NewFrame();
         ImGui::NewFrame();
 
@@ -167,18 +166,15 @@ int main(int, char**)
         ImDrawData* draw_data = ImGui::GetDrawData();
         const bool is_minimized = (draw_data->DisplaySize.x <= 0.0f || draw_data->DisplaySize.y <= 0.0f);
 
-        // Acquire a GPU command buffer
-        SDL_GPUCommandBuffer* command_buffer = SDL_AcquireGPUCommandBuffer(gpuDevice);
+        SDL_GPUCommandBuffer* command_buffer = SDL_AcquireGPUCommandBuffer(gpu_device); // Acquire a GPU command buffer
 
-        //Acquire a swapchain texture
         SDL_GPUTexture* swapchain_texture;
-        SDL_AcquireGPUSwapchainTexture(command_buffer, window, &swapchain_texture, nullptr, nullptr);
+        SDL_AcquireGPUSwapchainTexture(command_buffer, window, &swapchain_texture, nullptr, nullptr); // Acquire a swapchain texture
 
         if (swapchain_texture != nullptr && !is_minimized)
         {
-            // !!! THIS IS MANDATORY !!!
-            // Call Imgui_ImplSDLGPU_PrepareDrawData to upload the vertex/index buffer 
-            Imgui_ImplSDLGPU_PrepareDrawData(draw_data, command_buffer);
+            // This is mandatory: call Imgui_ImplSDLGPU3_PrepareDrawData() to upload the vertex/index buffer!
+            Imgui_ImplSDLGPU3_PrepareDrawData(draw_data, command_buffer);
 
             // Setup and start a render pass
             SDL_GPUColorTargetInfo target_info = {};
@@ -190,21 +186,26 @@ int main(int, char**)
             target_info.layer_or_depth_plane = 0;
             target_info.cycle = false;
             SDL_GPURenderPass* render_pass = SDL_BeginGPURenderPass(command_buffer, &target_info, 1, nullptr);
-            /// Render ImGui
-            ImGui_ImplSDLGPU_RenderDrawData(draw_data, command_buffer, render_pass);
+
+            // Render ImGui
+            ImGui_ImplSDLGPU3_RenderDrawData(draw_data, command_buffer, render_pass);
+
             SDL_EndGPURenderPass(render_pass);
         }
+
         // Submit the command buffer
         SDL_SubmitGPUCommandBuffer(command_buffer);
     }
     // Cleanup
-    SDL_WaitForGPUIdle(gpuDevice);
+    SDL_WaitForGPUIdle(gpu_device);
     ImGui_ImplSDL3_Shutdown();
-    ImGui_ImplSDLGPU_Shutdown();
+    ImGui_ImplSDLGPU3_Shutdown();
     ImGui::DestroyContext();
-    SDL_ReleaseWindowFromGPUDevice(gpuDevice, window);
-    SDL_DestroyGPUDevice(gpuDevice);
+
+    SDL_ReleaseWindowFromGPUDevice(gpu_device, window);
+    SDL_DestroyGPUDevice(gpu_device);
     SDL_DestroyWindow(window);
     SDL_Quit();
+
     return 0;
 }