| // Dear ImGui: standalone example application for Emscripten, using GLFW + WebGPU |
| // (Emscripten is a C++-to-javascript compiler, used to publish executables for the web. See https://emscripten.org/) |
| // If you are new to Dear ImGui, read documentation from the docs/ folder + read the top of imgui.cpp. |
| // Read online: https://github.com/ocornut/imgui/tree/master/docs |
| |
| #include "imgui.h" |
| #include "imgui_impl_glfw.h" |
| #include "imgui_impl_wgpu.h" |
| #include <stdio.h> |
| #include <emscripten.h> |
| #include <emscripten/html5.h> |
| #include <emscripten/html5_webgpu.h> |
| #include <GLFW/glfw3.h> |
| #include <webgpu/webgpu.h> |
| #include <webgpu/webgpu_cpp.h> |
| |
| // Global WebGPU required states |
| static WGPUDevice wgpu_device = NULL; |
| static WGPUSurface wgpu_surface = NULL; |
| static WGPUSwapChain wgpu_swap_chain = NULL; |
| static int wgpu_swap_chain_width = 0; |
| static int wgpu_swap_chain_height = 0; |
| |
| // States tracked across render frames |
| static bool show_demo_window = true; |
| static bool show_another_window = false; |
| static ImVec4 clear_color = ImVec4(0.45f, 0.55f, 0.60f, 1.00f); |
| |
| // Forward declarations |
| static bool init_wgpu(); |
| static void main_loop(void* window); |
| static void print_glfw_error(int error, const char* description); |
| static void print_wgpu_error(WGPUErrorType error_type, const char* message, void*); |
| |
| int main(int, char**) |
| { |
| glfwSetErrorCallback(print_glfw_error); |
| if (!glfwInit()) |
| return 1; |
| |
| // Make sure GLFW does not initialize any graphics context. |
| // This needs to be done explicitly later |
| glfwWindowHint(GLFW_CLIENT_API, GLFW_NO_API); |
| |
| GLFWwindow* window = glfwCreateWindow(1280, 720, "Dear ImGui GLFW+WebGPU example", NULL, NULL); |
| if (!window) |
| { |
| glfwTerminate(); |
| return 1; |
| } |
| |
| // Initialize the WebGPU environment |
| if (!init_wgpu()) |
| { |
| if (window) |
| glfwDestroyWindow(window); |
| glfwTerminate(); |
| return 1; |
| } |
| glfwShowWindow(window); |
| |
| // 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 |
| |
| // For an Emscripten build we are disabling file-system access, so let's not attempt to do a fopen() of the imgui.ini file. |
| // You may manually call LoadIniSettingsFromMemory() to load settings from your own storage. |
| io.IniFilename = NULL; |
| |
| // Setup Dear ImGui style |
| ImGui::StyleColorsDark(); |
| //ImGui::StyleColorsClassic(); |
| |
| // Setup Platform/Renderer backends |
| ImGui_ImplGlfw_InitForOther(window, true); |
| ImGui_ImplWGPU_Init(wgpu_device, 3, WGPUTextureFormat_RGBA8Unorm); |
| |
| // 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. |
| // - AddFontFromFileTTF() will return the ImFont* so you can store it if you need to select the font among multiple. |
| // - If the file cannot be loaded, the function will return NULL. Please handle those errors in your application (e.g. use an assertion, or display an error and quit). |
| // - The fonts will be rasterized at a given size (w/ oversampling) and stored into a texture when calling ImFontAtlas::Build()/GetTexDataAsXXXX(), which ImGui_ImplXXXX_NewFrame below will call. |
| // - Read 'docs/FONTS.md' for more instructions and details. |
| // - Remember that in C/C++ if you want to include a backslash \ in a string literal you need to write a double backslash \\ ! |
| // - Emscripten allows preloading a file or folder to be accessible at runtime. See Makefile for details. |
| //io.Fonts->AddFontDefault(); |
| #ifndef IMGUI_DISABLE_FILE_FUNCTIONS |
| io.Fonts->AddFontFromFileTTF("fonts/Roboto-Medium.ttf", 16.0f); |
| //io.Fonts->AddFontFromFileTTF("fonts/Cousine-Regular.ttf", 15.0f); |
| //io.Fonts->AddFontFromFileTTF("fonts/DroidSans.ttf", 16.0f); |
| //io.Fonts->AddFontFromFileTTF("fonts/ProggyTiny.ttf", 10.0f); |
| //ImFont* font = io.Fonts->AddFontFromFileTTF("fonts/ArialUni.ttf", 18.0f, NULL, io.Fonts->GetGlyphRangesJapanese()); |
| //IM_ASSERT(font != NULL); |
| #endif |
| |
| // This function will directly return and exit the main function. |
| // Make sure that no required objects get cleaned up. |
| // This way we can use the browsers 'requestAnimationFrame' to control the rendering. |
| emscripten_set_main_loop_arg(main_loop, window, 0, false); |
| |
| return 0; |
| } |
| |
| static bool init_wgpu() |
| { |
| wgpu_device = emscripten_webgpu_get_device(); |
| if (!wgpu_device) |
| return false; |
| |
| wgpuDeviceSetUncapturedErrorCallback(wgpu_device, print_wgpu_error, NULL); |
| |
| // Use C++ wrapper due to misbehavior in Emscripten. |
| // Some offset computation for wgpuInstanceCreateSurface in JavaScript |
| // seem to be inline with struct alignments in the C++ structure |
| wgpu::SurfaceDescriptorFromCanvasHTMLSelector html_surface_desc = {}; |
| html_surface_desc.selector = "#canvas"; |
| |
| wgpu::SurfaceDescriptor surface_desc = {}; |
| surface_desc.nextInChain = &html_surface_desc; |
| |
| // Use 'null' instance |
| wgpu::Instance instance = {}; |
| wgpu_surface = instance.CreateSurface(&surface_desc).Release(); |
| |
| return true; |
| } |
| |
| static void main_loop(void* window) |
| { |
| glfwPollEvents(); |
| |
| int width, height; |
| glfwGetFramebufferSize((GLFWwindow*) window, &width, &height); |
| |
| // React to changes in screen size |
| if (width != wgpu_swap_chain_width && height != wgpu_swap_chain_height) |
| { |
| ImGui_ImplWGPU_InvalidateDeviceObjects(); |
| |
| if (wgpu_swap_chain) |
| wgpuSwapChainRelease(wgpu_swap_chain); |
| |
| wgpu_swap_chain_width = width; |
| wgpu_swap_chain_height = height; |
| |
| WGPUSwapChainDescriptor swap_chain_desc = {}; |
| swap_chain_desc.usage = WGPUTextureUsage_RenderAttachment; |
| swap_chain_desc.format = WGPUTextureFormat_RGBA8Unorm; |
| swap_chain_desc.width = width; |
| swap_chain_desc.height = height; |
| swap_chain_desc.presentMode = WGPUPresentMode_Fifo; |
| wgpu_swap_chain = wgpuDeviceCreateSwapChain(wgpu_device, wgpu_surface, &swap_chain_desc); |
| |
| ImGui_ImplWGPU_CreateDeviceObjects(); |
| } |
| |
| // Start the Dear ImGui frame |
| ImGui_ImplWGPU_NewFrame(); |
| ImGui_ImplGlfw_NewFrame(); |
| ImGui::NewFrame(); |
| |
| // 1. Show the big demo window (Most of the sample code is in ImGui::ShowDemoWindow()! You can browse its code to learn more about Dear ImGui!). |
| if (show_demo_window) |
| ImGui::ShowDemoWindow(&show_demo_window); |
| |
| // 2. Show a simple window that we create ourselves. We use a Begin/End pair to created a named window. |
| { |
| static float f = 0.0f; |
| static int counter = 0; |
| |
| ImGui::Begin("Hello, world!"); // Create a window called "Hello, world!" and append into it. |
| |
| ImGui::Text("This is some useful text."); // Display some text (you can use a format strings too) |
| ImGui::Checkbox("Demo Window", &show_demo_window); // Edit bools storing our window open/close state |
| ImGui::Checkbox("Another Window", &show_another_window); |
| |
| ImGui::SliderFloat("float", &f, 0.0f, 1.0f); // Edit 1 float using a slider from 0.0f to 1.0f |
| ImGui::ColorEdit3("clear color", (float*)&clear_color); // Edit 3 floats representing a color |
| |
| if (ImGui::Button("Button")) // Buttons return true when clicked (most widgets return true when edited/activated) |
| counter++; |
| ImGui::SameLine(); |
| ImGui::Text("counter = %d", counter); |
| |
| ImGui::Text("Application average %.3f ms/frame (%.1f FPS)", 1000.0f / ImGui::GetIO().Framerate, ImGui::GetIO().Framerate); |
| ImGui::End(); |
| } |
| |
| // 3. Show another simple window. |
| if (show_another_window) |
| { |
| ImGui::Begin("Another Window", &show_another_window); // Pass a pointer to our bool variable (the window will have a closing button that will clear the bool when clicked) |
| ImGui::Text("Hello from another window!"); |
| if (ImGui::Button("Close Me")) |
| show_another_window = false; |
| ImGui::End(); |
| } |
| |
| // Rendering |
| ImGui::Render(); |
| |
| WGPURenderPassColorAttachment color_attachments = {}; |
| 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 }; |
| color_attachments.view = wgpuSwapChainGetCurrentTextureView(wgpu_swap_chain); |
| WGPURenderPassDescriptor render_pass_desc = {}; |
| render_pass_desc.colorAttachmentCount = 1; |
| render_pass_desc.colorAttachments = &color_attachments; |
| render_pass_desc.depthStencilAttachment = NULL; |
| |
| WGPUCommandEncoderDescriptor enc_desc = {}; |
| WGPUCommandEncoder encoder = wgpuDeviceCreateCommandEncoder(wgpu_device, &enc_desc); |
| |
| WGPURenderPassEncoder pass = wgpuCommandEncoderBeginRenderPass(encoder, &render_pass_desc); |
| ImGui_ImplWGPU_RenderDrawData(ImGui::GetDrawData(), pass); |
| wgpuRenderPassEncoderEnd(pass); |
| |
| WGPUCommandBufferDescriptor cmd_buffer_desc = {}; |
| WGPUCommandBuffer cmd_buffer = wgpuCommandEncoderFinish(encoder, &cmd_buffer_desc); |
| WGPUQueue queue = wgpuDeviceGetQueue(wgpu_device); |
| wgpuQueueSubmit(queue, 1, &cmd_buffer); |
| } |
| |
| static void print_glfw_error(int error, const char* description) |
| { |
| printf("Glfw Error %d: %s\n", error, description); |
| } |
| |
| static void print_wgpu_error(WGPUErrorType error_type, const char* message, void*) |
| { |
| const char* error_type_lbl = ""; |
| switch (error_type) |
| { |
| case WGPUErrorType_Validation: error_type_lbl = "Validation"; break; |
| case WGPUErrorType_OutOfMemory: error_type_lbl = "Out of memory"; break; |
| case WGPUErrorType_Unknown: error_type_lbl = "Unknown"; break; |
| case WGPUErrorType_DeviceLost: error_type_lbl = "Device lost"; break; |
| default: error_type_lbl = "Unknown"; |
| } |
| printf("%s error: %s\n", error_type_lbl, message); |
| } |