Add glfw wgpu desktop and multiviewport support #7132
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@@ -18,6 +18,7 @@ | |
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| // CHANGELOG | ||
| // (minor and older changes stripped away, please see git history for details) | ||
| // 2023-12-12: Add support for multi viewports. | ||
| // 2023-07-13: Use WGPUShaderModuleWGSLDescriptor's code instead of source. use WGPUMipmapFilterMode_Linear instead of WGPUFilterMode_Linear. (#6602) | ||
| // 2023-04-11: Align buffer sizes. Use WGSL shaders instead of precompiled SPIR-V. | ||
| // 2023-04-11: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX). | ||
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@@ -38,6 +39,7 @@ | |
| #include "imgui_impl_wgpu.h" | ||
| #include <limits.h> | ||
| #include <webgpu/webgpu.h> | ||
| #include <memory> | ||
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| // Dear ImGui prototypes from imgui_internal.h | ||
| extern ImGuiID ImHashData(const void* data_p, size_t data_size, ImU32 seed = 0); | ||
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@@ -72,8 +74,22 @@ struct Uniforms | |
| float Gamma; | ||
| }; | ||
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| // Forward declarations for multi-viewport support | ||
| static void ImGui_ImplWGPU_InitPlatformInterface(); | ||
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There was a problem hiding this comment. @ocornut, maybe it's worth renaming everything from WGPU to WebGPU? "wgpu" is a name of the Rust implementation and I see "WebGPU" being used everywhere (except for C API, which I find unfortunate). Otherwise people might think that this backend can only be used with wgpu and not with Dawn. There was a problem hiding this comment. I had chosen to go with WGPU purely based on how the C API was naming things, so yeah WebGPU is fine to go with as well. |
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| static void ImGui_ImplWGPU_ShutdownPlatformInterface(); | ||
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| // For multi-viewport support: | ||
| // Helper structure we store in the void* RendererUserData field of each ImGuiViewport to easily retrieve our backend data. | ||
| struct ImGui_ImplWGPU_ViewportData | ||
| { | ||
| ImGui_ImplWGPUH_Window Window; | ||
| ImGui_ImplWGPU_ViewportData() { } | ||
| ~ImGui_ImplWGPU_ViewportData() { } | ||
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There was a problem hiding this comment. These constructor and destructors are unnecessary and can be removed. There was a problem hiding this comment. That was a hang over of when I did have objects in there, yup should have been deleted |
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| }; | ||
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| struct ImGui_ImplWGPU_Data | ||
| { | ||
| WGPUInstance wgpuInstance = nullptr; | ||
| WGPUDevice wgpuDevice = nullptr; | ||
| WGPUQueue defaultQueue = nullptr; | ||
| WGPUTextureFormat renderTargetFormat = WGPUTextureFormat_Undefined; | ||
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@@ -211,6 +227,25 @@ static void SafeRelease(WGPUTexture& res) | |
| wgpuTextureRelease(res); | ||
| res = nullptr; | ||
| } | ||
| static void SafeRelease(WGPURenderPassEncoder& res) | ||
| { | ||
| if (res) | ||
| wgpuRenderPassEncoderRelease(res); | ||
| res = nullptr; | ||
| } | ||
| static void SafeRelease(WGPUCommandBuffer& res) | ||
| { | ||
| if (res) | ||
| wgpuCommandBufferRelease(res); | ||
| res = nullptr; | ||
| } | ||
| static void SafeRelease(WGPUCommandEncoder& res) | ||
| { | ||
| if (res) | ||
| wgpuCommandEncoderRelease(res); | ||
| res = nullptr; | ||
| } | ||
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| static void SafeRelease(RenderResources& res) | ||
| { | ||
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@@ -230,6 +265,18 @@ static void SafeRelease(FrameResources& res) | |
| SafeRelease(res.IndexBufferHost); | ||
| SafeRelease(res.VertexBufferHost); | ||
| } | ||
| static void SafeRelease(WGPUSwapChain& res) | ||
| { | ||
| if (res) | ||
| wgpuSwapChainRelease(res); | ||
| res = nullptr; | ||
| } | ||
| static void SafeRelease(WGPUSurface& res) | ||
| { | ||
| if (res) | ||
| wgpuSurfaceRelease(res); | ||
| res = nullptr; | ||
| } | ||
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| static WGPUProgrammableStageDescriptor ImGui_ImplWGPU_CreateShaderModule(const char* wgsl_source) | ||
| { | ||
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@@ -699,7 +746,7 @@ void ImGui_ImplWGPU_InvalidateDeviceObjects() | |
| SafeRelease(bd->pFrameResources[i]); | ||
| } | ||
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| bool ImGui_ImplWGPU_Init(WGPUDevice device, int num_frames_in_flight, WGPUTextureFormat rt_format, WGPUTextureFormat depth_format, WGPUInstance instance) | ||
| { | ||
| ImGuiIO& io = ImGui::GetIO(); | ||
| IM_ASSERT(io.BackendRendererUserData == nullptr && "Already initialized a renderer backend!"); | ||
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@@ -709,7 +756,11 @@ bool ImGui_ImplWGPU_Init(WGPUDevice device, int num_frames_in_flight, WGPUTextur | |
| io.BackendRendererUserData = (void*)bd; | ||
| io.BackendRendererName = "imgui_impl_webgpu"; | ||
| io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset; // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes. | ||
| #ifndef __EMSCRIPTEN__ | ||
| io.BackendFlags |= ImGuiBackendFlags_RendererHasViewports; // Enable multiviewport on desktop. | ||
| #endif | ||
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| bd->wgpuInstance = instance; | ||
| bd->wgpuDevice = device; | ||
| bd->defaultQueue = wgpuDeviceGetQueue(bd->wgpuDevice); | ||
| bd->renderTargetFormat = rt_format; | ||
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@@ -739,6 +790,12 @@ bool ImGui_ImplWGPU_Init(WGPUDevice device, int num_frames_in_flight, WGPUTextur | |
| fr->VertexBufferSize = 5000; | ||
| } | ||
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| if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable) | ||
| { | ||
| IM_ASSERT(instance != nullptr && "WGPUInstance required for multi viewport!"); | ||
| ImGui_ImplWGPU_InitPlatformInterface(); | ||
| } | ||
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| return true; | ||
| } | ||
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@@ -756,6 +813,10 @@ void ImGui_ImplWGPU_Shutdown() | |
| bd->numFramesInFlight = 0; | ||
| bd->frameIndex = UINT_MAX; | ||
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| // Clean up windows | ||
| if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable) | ||
| ImGui_ImplWGPU_ShutdownPlatformInterface(); | ||
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| io.BackendRendererName = nullptr; | ||
| io.BackendRendererUserData = nullptr; | ||
| io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset; | ||
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@@ -769,6 +830,153 @@ void ImGui_ImplWGPU_NewFrame() | |
| ImGui_ImplWGPU_CreateDeviceObjects(); | ||
| } | ||
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| //-------------------------------------------------------------------------------------------------------- | ||
| // 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.. | ||
| //-------------------------------------------------------------------------------------------------------- | ||
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| static void ImGui_ImplWGPU_CreateWindow(ImGuiViewport* viewport) | ||
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There was a problem hiding this comment. This should probably be moved out of the backend and user should provide this instead - there's no easy way to handle this for every platform/WebGPU impl. There was a problem hiding this comment. 100% this is the main thing I was struggling with trying to fix, would it be just a callback that a user would need to assign to ? |
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| { | ||
| ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData(); | ||
| ImGui_ImplWGPU_ViewportData* vd = IM_NEW(ImGui_ImplWGPU_ViewportData)(); | ||
| viewport->RendererUserData = vd; | ||
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| WGPUChainedStruct chainedDescriptor = {}; | ||
| // ------ ISSUE unknown for linux and apple ------------- | ||
| #ifndef __EMSCRIPTEN__ | ||
| #ifdef _WIN32 | ||
| chainedDescriptor.sType = WGPUSType_SurfaceDescriptorFromWindowsHWND; | ||
| std::unique_ptr<WGPUSurfaceDescriptorFromWindowsHWND> surfaceDescFromHandle = std::make_unique<WGPUSurfaceDescriptorFromWindowsHWND>(); | ||
| surfaceDescFromHandle->hwnd = viewport->PlatformHandleRaw; | ||
| #elif defined(__APPLE__) | ||
| chainedDescriptor.sType = WGPUSType_SurfaceDescriptorFromMetalLayer; | ||
| std::unique_ptr<WGPUSurfaceDescriptorFromMetalLayer> surfaceDescFromHandle = std::make_unique<WGPUSurfaceDescriptorFromMetalLayer>(); | ||
| NSWindow* ns_window = viewport->PlatformHandleRaw; | ||
| [ns_window.contentView setWantsLayer : YES]; | ||
| metal_layer = [CAMetalLayer layer]; | ||
| [ns_window.contentView setLayer : metal_layer] ; | ||
| surfaceDescFromHandle->layer = metal_layer; | ||
| // #elif defined(DAWN_USE_WAYLAND) | ||
| // struct wl_display* wayland_display = glfwGetWaylandDisplay(); | ||
| // struct wl_surface* wayland_surface = glfwGetWaylandWindow(window); | ||
| // chainedDescriptor.sType = WGPUSType_SurfaceDescriptorFromWindowsHWND; | ||
| // std::unique_ptr<WGPUSurfaceDescriptorFromWaylandSurface> surfaceDescFromHandle = std::make_unique<WGPUSurfaceDescriptorFromWaylandSurface>(); | ||
| // surfaceDescFromHandle->display = wayland_display; | ||
| // surfaceDescFromHandle->surface = wayland_surface; | ||
| // #else | ||
| // Display* x11_display = glfwGetX11Display(); | ||
| // Window x11_window = glfwGetX11Window((GLFWwindow*) viewport->PlatformHandle); | ||
| // chainedDescriptor.sType = WGPUSType_SurfaceDescriptorFromXlibWindow; | ||
| // std::unique_ptr<WGPUSurfaceDescriptorFromXlibWindow> surfaceDescFromHandle = std::make_unique<WGPUSurfaceDescriptorFromXlibWindow>(); | ||
| // surfaceDescFromHandle->display = x11_display; | ||
| // surfaceDescFromHandle->window = x11_window; | ||
| #endif | ||
| // ------------------------------------------------------ | ||
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| surfaceDescFromHandle->chain = chainedDescriptor; | ||
| WGPUSurfaceDescriptor surfaceDescriptor = {}; | ||
| surfaceDescriptor.nextInChain = &surfaceDescFromHandle->chain; | ||
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| vd->Window.surface = wgpuInstanceCreateSurface(bd->wgpuInstance, &surfaceDescriptor); | ||
| #endif | ||
| WGPUSwapChainDescriptor swapDescriptor = {}; | ||
| swapDescriptor.usage = WGPUTextureUsage_RenderAttachment; | ||
| swapDescriptor.format = bd->renderTargetFormat; | ||
| swapDescriptor.width = viewport->Size.x; | ||
| swapDescriptor.height = viewport->Size.y; | ||
| swapDescriptor.presentMode = WGPUPresentMode_Fifo; | ||
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| vd->Window.swapChain = wgpuDeviceCreateSwapChain(bd->wgpuDevice, vd->Window.surface, &swapDescriptor); | ||
| } | ||
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| static void ImGui_ImplWGPU_DestroyWindow(ImGuiViewport* viewport) | ||
| { | ||
| if (ImGui_ImplWGPU_ViewportData* vd = (ImGui_ImplWGPU_ViewportData*)viewport->RendererUserData) | ||
| { | ||
| SafeRelease(vd->Window.swapChain); | ||
| SafeRelease(vd->Window.surface); | ||
| IM_DELETE(vd); | ||
| } | ||
| viewport->RendererUserData = nullptr; | ||
| } | ||
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| static void ImGui_ImplWGPU_SetWindowSize(ImGuiViewport* viewport, ImVec2 size) | ||
| { | ||
| ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData(); | ||
| ImGui_ImplWGPU_ViewportData* vd = (ImGui_ImplWGPU_ViewportData*)viewport->RendererUserData; | ||
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| SafeRelease(vd->Window.swapChain); | ||
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| WGPUSwapChainDescriptor swapDescriptor = {}; | ||
| swapDescriptor.usage = WGPUTextureUsage_RenderAttachment; | ||
| swapDescriptor.format = bd->renderTargetFormat; | ||
| swapDescriptor.width = size.x; | ||
| swapDescriptor.height = size.y; | ||
| swapDescriptor.presentMode = WGPUPresentMode_Fifo; | ||
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| vd->Window.swapChain = wgpuDeviceCreateSwapChain(bd->wgpuDevice, vd->Window.surface, &swapDescriptor); | ||
| } | ||
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| static void ImGui_ImplWGPU_RenderWindow(ImGuiViewport* viewport, void*) | ||
| { | ||
| ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData(); | ||
| ImGui_ImplWGPU_ViewportData* vd = (ImGui_ImplWGPU_ViewportData*)viewport->RendererUserData; | ||
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| ImVec4 clear_color = ImVec4(0.0f, 0.0f, 0.0f, 1.0f); | ||
| WGPURenderPassColorAttachment color_attachments = {}; | ||
| color_attachments.view = wgpuSwapChainGetCurrentTextureView(vd->Window.swapChain); | ||
| color_attachments.loadOp = WGPULoadOp_Clear; | ||
| color_attachments.storeOp = WGPUStoreOp_Store; | ||
| color_attachments.clearValue = { clear_color.x * clear_color.w, clear_color.y * clear_color.w, clear_color.z * clear_color.w, clear_color.w }; | ||
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There was a problem hiding this comment. Doesn't work without this: color_attachments.depthSlice = WGPU_DEPTH_SLICE_UNDEFINED;There was a problem hiding this comment. I think this is a new requirement imposed in a version of dawn that I had yet to work with, If that is required then putting it in should be done. |
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| WGPURenderPassDescriptor render_pass_desc = {}; | ||
| render_pass_desc.colorAttachmentCount = 1; | ||
| render_pass_desc.colorAttachments = &color_attachments; | ||
| render_pass_desc.depthStencilAttachment = nullptr; | ||
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| WGPUCommandEncoderDescriptor enc_desc = {}; | ||
| WGPUCommandEncoder encoder = wgpuDeviceCreateCommandEncoder(bd->wgpuDevice, &enc_desc); | ||
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| WGPURenderPassEncoder pass = wgpuCommandEncoderBeginRenderPass(encoder, &render_pass_desc); | ||
| ImGui_ImplWGPU_RenderDrawData(viewport->DrawData, pass); | ||
| wgpuRenderPassEncoderEnd(pass); | ||
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| WGPUCommandBufferDescriptor cmd_buffer_desc = {}; | ||
| WGPUCommandBuffer cmd_buffer = wgpuCommandEncoderFinish(encoder, &cmd_buffer_desc); | ||
| WGPUQueue queue = wgpuDeviceGetQueue(bd->wgpuDevice); | ||
| wgpuQueueSubmit(queue, 1, &cmd_buffer); | ||
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| SafeRelease(color_attachments.view); | ||
| SafeRelease(pass); | ||
| SafeRelease(encoder); | ||
| SafeRelease(cmd_buffer); | ||
| } | ||
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| static void ImGui_ImplWGPU_SwapBuffers(ImGuiViewport* viewport, void*) | ||
| { | ||
| ImGui_ImplWGPU_ViewportData* vd = (ImGui_ImplWGPU_ViewportData*)viewport->RendererUserData; | ||
| wgpuSwapChainPresent(vd->Window.swapChain); | ||
| } | ||
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| void ImGui_ImplWGPU_InitPlatformInterface() | ||
| { | ||
| ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO(); | ||
| platform_io.Renderer_CreateWindow = ImGui_ImplWGPU_CreateWindow; | ||
| platform_io.Renderer_DestroyWindow = ImGui_ImplWGPU_DestroyWindow; | ||
| platform_io.Renderer_SetWindowSize = ImGui_ImplWGPU_SetWindowSize; | ||
| platform_io.Renderer_RenderWindow = ImGui_ImplWGPU_RenderWindow; | ||
| platform_io.Renderer_SwapBuffers = ImGui_ImplWGPU_SwapBuffers; | ||
| } | ||
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| void ImGui_ImplWGPU_ShutdownPlatformInterface() | ||
| { | ||
| ImGui::DestroyPlatformWindows(); | ||
| } | ||
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| //----------------------------------------------------------------------------- | ||
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| #endif // #ifndef IMGUI_DISABLE | ||
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| Original file line number | Diff line number | Diff line change |
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| @@ -0,0 +1,64 @@ | ||
| # Example usage: | ||
| # cmake -B build -g "Ninja" | ||
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There was a problem hiding this comment. Probably better to list all steps and explain that you need to have Dawn cloned at "external/libraries/dawn": mkdir build && cd build
cmake ..
cmake --build .The second step would look like this, if you add an option to specify Dawn's dir: cmake .. -DIMGUI_DAWN_DIR=<dir of cloned Dawn repo> |
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| cmake_minimum_required(VERSION 3.10.2) | ||
| project(imgui_example_emscripten_wgpu C CXX) | ||
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| if(NOT CMAKE_BUILD_TYPE) | ||
| set(CMAKE_BUILD_TYPE Debug CACHE STRING "" FORCE) | ||
| endif() | ||
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| set(CMAKE_CXX_STANDARD 17) | ||
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There was a problem hiding this comment. Isn't Dear ImGui still C++11? (I see that other examples are) - what are some C++17 features that you need here? There was a problem hiding this comment. Another hangup on copying from the vulkan cmake (might want to check the vulkan backend and examples to maybe nip those unless they are needed I assume) |
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| set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -DVK_PROTOTYPES") | ||
| set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DVK_PROTOTYPES") | ||
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There was a problem hiding this comment. Is it really needed? Compiled fine without this for me. There was a problem hiding this comment. Yeah these are not needed, was me being sloppy checking the cmake. (again copied from vulkan but this time I think vulkan needs those) |
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| set(BUILD_TESTING OFF) | ||
| set(BUILD_TESTING_STATIC OFF) | ||
| set(BUILD_TESTING_SHARED OFF) | ||
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| # Dear ImGui | ||
| set(IMGUI_DIR ../../) | ||
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There was a problem hiding this comment. Better do this: set(IMGUI_DIR "${CMAKE_CURRENT_LIST_DIR}/../..")
There was a problem hiding this comment. Looks good, might want to do the same change in the vulkan example too. |
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| include_directories(${IMGUI_DIR} ${IMGUI_DIR}/backends ..) | ||
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There was a problem hiding this comment. Better to use this: target_include_directories(example_emscripten_wgpu PRIVATE ${IMGUI_DIR} ${IMGUI_DIR}/backends) |
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| # Libraries | ||
| if(EMSCRIPTEN) | ||
| set(LIBRARIES glfw) | ||
| add_compile_options(-sDISABLE_EXCEPTION_CATCHING=1 -DIMGUI_DISABLE_FILE_FUNCTIONS=1) | ||
| else() | ||
| # Dawn wgpu desktop | ||
| set(DAWN_FETCH_DEPENDENCIES ON) | ||
| add_subdirectory("external/libraries/dawn" dawn EXCLUDE_FROM_ALL) # point this to up to date dawn repo | ||
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There was a problem hiding this comment. It would probably be better to allow users to set DAWN_DIR variable and use that instead so that
There was a problem hiding this comment. I was unsure the best approach to handle this, might need to account for wgpu-native as well (which I had not) |
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| set(LIBRARIES webgpu_dawn webgpu_cpp webgpu_glfw glfw) | ||
| endif() | ||
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| add_executable(example_emscripten_wgpu | ||
| main.cpp | ||
| ${IMGUI_DIR}/backends/imgui_impl_glfw.cpp | ||
| ${IMGUI_DIR}/backends/imgui_impl_wgpu.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 | ||
| ) | ||
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| # Libraries | ||
| if(EMSCRIPTEN) | ||
| set_target_properties(example_emscripten_wgpu PROPERTIES OUTPUT_NAME "index") | ||
| set_target_properties(example_emscripten_wgpu PROPERTIES SUFFIX ".html") | ||
| set_target_properties(example_emscripten_wgpu PROPERTIES RUNTIME_OUTPUT_DIRECTORY ${CMAKE_SOURCE_DIR}/web) | ||
| set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} --shell-file ${CMAKE_SOURCE_DIR}/../libs/emscripten/shell_minimal.html") | ||
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| target_link_options(example_emscripten_wgpu PRIVATE | ||
| "-sUSE_WEBGPU=1" | ||
| "-sUSE_GLFW=3" | ||
| "-sWASM=1" | ||
| "-sALLOW_MEMORY_GROWTH=1" | ||
| "-sNO_EXIT_RUNTIME=0" | ||
| "-sASSERTIONS=1" | ||
| "-sDISABLE_EXCEPTION_CATCHING=1" | ||
| "-sNO_FILESYSTEM=1" | ||
| ) | ||
| endif() | ||
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| target_link_libraries(example_emscripten_wgpu ${LIBRARIES}) | ||
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Can be removed if
ImGui_ImplWGPU_CreateWindowis not included in the backend.