From 6cd66dde6929c17cee265a9f09457ed03150adef Mon Sep 17 00:00:00 2001 From: Zelif Date: Sat, 16 Dec 2023 05:14:28 +1100 Subject: [PATCH] Update example_emscripten_wgpu demo Split emscripten only sections off Added callbacks for getting device & adapter Added multi viewport code Added swapchain creation function Added temporary canvas resize on creation until #6751 is merged in (Refreshing will resize the canvas) --- examples/example_emscripten_wgpu/main.cpp | 329 ++++++++++++++++++++++ examples/example_glfw_wgpu/web/index.html | 5 + 2 files changed, 334 insertions(+) create mode 100644 examples/example_emscripten_wgpu/main.cpp diff --git a/examples/example_emscripten_wgpu/main.cpp b/examples/example_emscripten_wgpu/main.cpp new file mode 100644 index 000000000000..428bb8953277 --- /dev/null +++ b/examples/example_emscripten_wgpu/main.cpp @@ -0,0 +1,329 @@ +// 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/) + +// Learn about Dear ImGui: +// - FAQ https://dearimgui.com/faq +// - Getting Started https://dearimgui.com/getting-started +// - Documentation https://dearimgui.com/docs (same as your local docs/ folder). +// - Introduction, links and more at the top of imgui.cpp + +#include "imgui.h" +#include "imgui_impl_glfw.h" +#include "imgui_impl_wgpu.h" +#include +#ifdef __EMSCRIPTEN__ +#include +#include +#include +#else +#include +#endif +#include +#include +#include + +// Global WebGPU required states +static wgpu::Instance wgpu_instance = nullptr; +static wgpu::Surface wgpu_surface = nullptr; +static wgpu::Device wgpu_device = nullptr; +static WGPUTextureFormat wgpu_preferred_fmt = WGPUTextureFormat_BGRA8Unorm; +static WGPUSwapChain wgpu_swap_chain = nullptr; +static int wgpu_swap_chain_width = 1280; +static int wgpu_swap_chain_height = 720; + +// Forward declarations +static void MainLoopStep(void* window); +static void InitWGPU(void (*callback)(wgpu::Device)); +static bool CreateWGPUSurface(GLFWwindow* window); +static void CreateSwapChain(int width, int height); +static void print_glfw_error(int error, const char* description); +static void print_wgpu_error(WGPUErrorType error_type, const char* message, void*); +static void RequestDeviceCallback(WGPURequestDeviceStatus status, WGPUDevice cDevice, const char* message, void* userdata); +static void RequestAdapterCallback(WGPURequestAdapterStatus status, WGPUAdapter cAdapter,const char* message, void* userdata); +// ------ Remove pending https://github.com/ocornut/imgui/pull/6751 +// glfwGetFramebufferSize not reporting changes in size +#if defined(__EMSCRIPTEN__) +EM_JS(int, canvas_get_width, (), { + return document.getElementById('canvas').width; +}); + +EM_JS(int, canvas_get_height, (), { + return document.getElementById('canvas').height; +}); +#endif +// ------------------------------- + +// Main code +int main(int, char**) +{ + InitWGPU([](wgpu::Device device) { + wgpu_device = device; + + glfwSetErrorCallback(print_glfw_error); + if (!glfwInit()) + exit(1); + +#if defined(__EMSCRIPTEN__) + wgpu_swap_chain_width = canvas_get_width(); + wgpu_swap_chain_height = canvas_get_height(); +#endif + // 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(wgpu_swap_chain_width, wgpu_swap_chain_height, "Dear ImGui GLFW+WebGPU example", nullptr, nullptr); + if (!window) + { + glfwTerminate(); + exit(1); + } + + // Initialize the WebGPU surface + if (!CreateWGPUSurface(window)) + { + if (window) + glfwDestroyWindow(window); + glfwTerminate(); + exit(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 + io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable; // Enable Multiviewport for docking branch + + // 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. +#if defined(__EMSCRIPTEN__) + io.IniFilename = nullptr; +#endif + + // Setup Dear ImGui style + ImGui::StyleColorsDark(); + //ImGui::StyleColorsLight(); + + // Setup Platform/Renderer backends + ImGui_ImplGlfw_InitForOther(window, true); + ImGui_ImplWGPU_Init(wgpu_device.Get(), 3, wgpu_preferred_fmt, WGPUTextureFormat_Undefined, wgpu_instance.Get()); + + CreateSwapChain(wgpu_swap_chain_width, wgpu_swap_chain_height); + + // 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 a nullptr. 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. + // - Use '#define IMGUI_ENABLE_FREETYPE' in your imconfig file to use Freetype for higher quality font rendering. + // - 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/segoeui.ttf", 18.0f); + io.Fonts->AddFontFromFileTTF("fonts/DroidSans.ttf", 16.0f); + //io.Fonts->AddFontFromFileTTF("fonts/Roboto-Medium.ttf", 16.0f); + //io.Fonts->AddFontFromFileTTF("fonts/Cousine-Regular.ttf", 15.0f); + //io.Fonts->AddFontFromFileTTF("fonts/ProggyTiny.ttf", 10.0f); + //ImFont* font = io.Fonts->AddFontFromFileTTF("fonts/ArialUni.ttf", 18.0f, nullptr, io.Fonts->GetGlyphRangesJapanese()); + //IM_ASSERT(font != nullptr); +#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. +#if defined(__EMSCRIPTEN__) + emscripten_set_main_loop_arg(MainLoopStep, window, 0, false); +#else + while (!glfwWindowShouldClose(window)) { + MainLoopStep(window); + wgpuSwapChainPresent(wgpu_swap_chain); + if (ImGui::GetIO().ConfigFlags & ImGuiConfigFlags_ViewportsEnable) + { + ImGui::UpdatePlatformWindows(); + ImGui::RenderPlatformWindowsDefault(); + } + } +#endif + }); + + return 0; +} + +static void RequestDeviceCallback(WGPURequestDeviceStatus status, WGPUDevice cDevice, const char* message, void* userdata) +{ + wgpu::Device device = wgpu::Device::Acquire(cDevice); + wgpuDeviceSetUncapturedErrorCallback(cDevice, print_wgpu_error, nullptr); + reinterpret_cast(userdata)(device); +} + +static void RequestAdapterCallback(WGPURequestAdapterStatus status, WGPUAdapter cAdapter, const char* message, void* userdata) +{ + if (status != WGPURequestAdapterStatus_Success) { + exit(0); + } + + wgpu::Adapter adapter = wgpu::Adapter::Acquire(cAdapter); + + adapter.RequestDevice(nullptr, RequestDeviceCallback, userdata); +} + +static void InitWGPU(void (*callback)(wgpu::Device)) +{ + wgpu_instance = wgpu::Instance::Acquire(wgpuCreateInstance(nullptr)); + wgpu_instance.RequestAdapter(nullptr, RequestAdapterCallback, reinterpret_cast(callback)); +} + +static bool CreateWGPUSurface(GLFWwindow* window) +{ + // 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 +#if defined(__EMSCRIPTEN__) + wgpu::SurfaceDescriptorFromCanvasHTMLSelector html_surface_desc = {}; + html_surface_desc.selector = "#canvas"; + + wgpu::SurfaceDescriptor surfaceDesc = {}; + surfaceDesc.nextInChain = &html_surface_desc; + + wgpu_surface = wgpu_instance.CreateSurface(&surfaceDesc); +#else + wgpu_surface = wgpu::glfw::CreateSurfaceForWindow(wgpu_instance, window); +#endif + + return wgpu_surface != nullptr; +} + +static void CreateSwapChain(int width, int height) +{ + if (wgpu_swap_chain) { + wgpuSwapChainRelease(wgpu_swap_chain); + wgpu_swap_chain = nullptr; + } + + wgpu_swap_chain_width = width; + wgpu_swap_chain_height = height; + + WGPUSwapChainDescriptor swapDescriptor = {}; + swapDescriptor.usage = WGPUTextureUsage_RenderAttachment; + swapDescriptor.format = wgpu_preferred_fmt; + swapDescriptor.width = wgpu_swap_chain_width; + swapDescriptor.height = wgpu_swap_chain_height; + swapDescriptor.presentMode = WGPUPresentMode_Fifo; + + wgpu_swap_chain = wgpuDeviceCreateSwapChain(wgpu_device.Get(), wgpu_surface.Get(), &swapDescriptor); +} + +static void MainLoopStep(void* window) +{ + ImGuiIO& io = ImGui::GetIO(); + + 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(); + CreateSwapChain(width, height); + ImGui_ImplWGPU_CreateDeviceObjects(); + } + + // Start the Dear ImGui frame + ImGui_ImplWGPU_NewFrame(); + ImGui_ImplGlfw_NewFrame(); + ImGui::NewFrame(); + + // Our state + // (we use static, which essentially makes the variable globals, as a convenience to keep the example code easy to follow) + 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); + + // 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 create 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 / io.Framerate, io.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 = nullptr; + + WGPUCommandEncoderDescriptor enc_desc = {}; + WGPUCommandEncoder encoder = wgpuDeviceCreateCommandEncoder(wgpu_device.Get(), &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.Get()); + 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); +} diff --git a/examples/example_glfw_wgpu/web/index.html b/examples/example_glfw_wgpu/web/index.html index a2a91c4a75f8..e13b6a333d64 100644 --- a/examples/example_glfw_wgpu/web/index.html +++ b/examples/example_glfw_wgpu/web/index.html @@ -73,6 +73,11 @@ } { + // ------ Remove once https://github.com/ocornut/imgui/pull/6751 is merged in + let canvas = document.getElementById('canvas'); + canvas.width = window.innerWidth; + canvas.height = window.innerHeight; + // ------ const js = document.createElement('script'); js.async = true; js.src = "index.js";