// dear imgui: Renderer for WebGPU // This needs to be used along with a Platform Binding (e.g. GLFW) // (Please note that WebGPU is currently experimental, will not run on non-beta browsers, and may break.) // Implemented features: // [X] Renderer: User texture binding. Use 'WGPUTextureView' as ImTextureID. Read the FAQ about ImTextureID! // [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices. // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this. // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need. // 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 // CHANGELOG // (minor and older changes stripped away, please see git history for details) // 2021-11-29: Passing explicit buffer sizes to wgpuRenderPassEncoderSetVertexBuffer()/wgpuRenderPassEncoderSetIndexBuffer(). // 2021-08-24: Fix for latest specs. // 2021-05-24: Add support for draw_data->FramebufferScale. // 2021-05-19: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement) // 2021-05-16: Update to latest WebGPU specs (compatible with Emscripten 2.0.20 and Chrome Canary 92). // 2021-02-18: Change blending equation to preserve alpha in output buffer. // 2021-01-28: Initial version. #include "imgui.h" #include "imgui_impl_wgpu.h" #include #include #define HAS_EMSCRIPTEN_VERSION(major, minor, tiny) (__EMSCRIPTEN_major__ > (major) || (__EMSCRIPTEN_major__ == (major) && __EMSCRIPTEN_minor__ > (minor)) || (__EMSCRIPTEN_major__ == (major) && __EMSCRIPTEN_minor__ == (minor) && __EMSCRIPTEN_tiny__ >= (tiny))) #if defined(__EMSCRIPTEN__) && !HAS_EMSCRIPTEN_VERSION(2, 0, 20) #error "Requires at least emscripten 2.0.20" #endif // Dear ImGui prototypes from imgui_internal.h extern ImGuiID ImHashData(const void* data_p, size_t data_size, ImU32 seed = 0); // WebGPU data static WGPUDevice g_wgpuDevice = NULL; static WGPUQueue g_defaultQueue = NULL; static WGPUTextureFormat g_renderTargetFormat = WGPUTextureFormat_Undefined; static WGPURenderPipeline g_pipelineState = NULL; struct RenderResources { WGPUTexture FontTexture; // Font texture WGPUTextureView FontTextureView; // Texture view for font texture WGPUSampler Sampler; // Sampler for the font texture WGPUBuffer Uniforms; // Shader uniforms WGPUBindGroup CommonBindGroup; // Resources bind-group to bind the common resources to pipeline ImGuiStorage ImageBindGroups; // Resources bind-group to bind the font/image resources to pipeline (this is a key->value map) WGPUBindGroup ImageBindGroup; // Default font-resource of Dear ImGui WGPUBindGroupLayout ImageBindGroupLayout; // Cache layout used for the image bind group. Avoids allocating unnecessary JS objects when working with WebASM }; static RenderResources g_resources; struct FrameResources { WGPUBuffer IndexBuffer; WGPUBuffer VertexBuffer; ImDrawIdx* IndexBufferHost; ImDrawVert* VertexBufferHost; int IndexBufferSize; int VertexBufferSize; }; static FrameResources* g_pFrameResources = NULL; static unsigned int g_numFramesInFlight = 0; static unsigned int g_frameIndex = UINT_MAX; struct Uniforms { float MVP[4][4]; }; //----------------------------------------------------------------------------- // SHADERS //----------------------------------------------------------------------------- // glsl_shader.vert, compiled with: // # glslangValidator -V -x -o glsl_shader.vert.u32 glsl_shader.vert /* #version 450 core layout(location = 0) in vec2 aPos; layout(location = 1) in vec2 aUV; layout(location = 2) in vec4 aColor; layout(set=0, binding = 0) uniform transform { mat4 mvp; }; out gl_PerVertex { vec4 gl_Position; }; layout(location = 0) out struct { vec4 Color; vec2 UV; } Out; void main() { Out.Color = aColor; Out.UV = aUV; gl_Position = mvp * vec4(aPos, 0, 1); } */ static uint32_t __glsl_shader_vert_spv[] = { 0x07230203,0x00010000,0x00080007,0x0000002c,0x00000000,0x00020011,0x00000001,0x0006000b, 0x00000001,0x4c534c47,0x6474732e,0x3035342e,0x00000000,0x0003000e,0x00000000,0x00000001, 0x000a000f,0x00000000,0x00000004,0x6e69616d,0x00000000,0x0000000b,0x0000000f,0x00000015, 0x0000001b,0x00000023,0x00030003,0x00000002,0x000001c2,0x00040005,0x00000004,0x6e69616d, 0x00000000,0x00030005,0x00000009,0x00000000,0x00050006,0x00000009,0x00000000,0x6f6c6f43, 0x00000072,0x00040006,0x00000009,0x00000001,0x00005655,0x00030005,0x0000000b,0x0074754f, 0x00040005,0x0000000f,0x6c6f4361,0x0000726f,0x00030005,0x00000015,0x00565561,0x00060005, 0x00000019,0x505f6c67,0x65567265,0x78657472,0x00000000,0x00060006,0x00000019,0x00000000, 0x505f6c67,0x7469736f,0x006e6f69,0x00030005,0x0000001b,0x00000000,0x00050005,0x0000001d, 0x6e617274,0x726f6673,0x0000006d,0x00040006,0x0000001d,0x00000000,0x0070766d,0x00030005, 0x0000001f,0x00000000,0x00040005,0x00000023,0x736f5061,0x00000000,0x00040047,0x0000000b, 0x0000001e,0x00000000,0x00040047,0x0000000f,0x0000001e,0x00000002,0x00040047,0x00000015, 0x0000001e,0x00000001,0x00050048,0x00000019,0x00000000,0x0000000b,0x00000000,0x00030047, 0x00000019,0x00000002,0x00040048,0x0000001d,0x00000000,0x00000005,0x00050048,0x0000001d, 0x00000000,0x00000023,0x00000000,0x00050048,0x0000001d,0x00000000,0x00000007,0x00000010, 0x00030047,0x0000001d,0x00000002,0x00040047,0x0000001f,0x00000022,0x00000000,0x00040047, 0x0000001f,0x00000021,0x00000000,0x00040047,0x00000023,0x0000001e,0x00000000,0x00020013, 0x00000002,0x00030021,0x00000003,0x00000002,0x00030016,0x00000006,0x00000020,0x00040017, 0x00000007,0x00000006,0x00000004,0x00040017,0x00000008,0x00000006,0x00000002,0x0004001e, 0x00000009,0x00000007,0x00000008,0x00040020,0x0000000a,0x00000003,0x00000009,0x0004003b, 0x0000000a,0x0000000b,0x00000003,0x00040015,0x0000000c,0x00000020,0x00000001,0x0004002b, 0x0000000c,0x0000000d,0x00000000,0x00040020,0x0000000e,0x00000001,0x00000007,0x0004003b, 0x0000000e,0x0000000f,0x00000001,0x00040020,0x00000011,0x00000003,0x00000007,0x0004002b, 0x0000000c,0x00000013,0x00000001,0x00040020,0x00000014,0x00000001,0x00000008,0x0004003b, 0x00000014,0x00000015,0x00000001,0x00040020,0x00000017,0x00000003,0x00000008,0x0003001e, 0x00000019,0x00000007,0x00040020,0x0000001a,0x00000003,0x00000019,0x0004003b,0x0000001a, 0x0000001b,0x00000003,0x00040018,0x0000001c,0x00000007,0x00000004,0x0003001e,0x0000001d, 0x0000001c,0x00040020,0x0000001e,0x00000002,0x0000001d,0x0004003b,0x0000001e,0x0000001f, 0x00000002,0x00040020,0x00000020,0x00000002,0x0000001c,0x0004003b,0x00000014,0x00000023, 0x00000001,0x0004002b,0x00000006,0x00000025,0x00000000,0x0004002b,0x00000006,0x00000026, 0x3f800000,0x00050036,0x00000002,0x00000004,0x00000000,0x00000003,0x000200f8,0x00000005, 0x0004003d,0x00000007,0x00000010,0x0000000f,0x00050041,0x00000011,0x00000012,0x0000000b, 0x0000000d,0x0003003e,0x00000012,0x00000010,0x0004003d,0x00000008,0x00000016,0x00000015, 0x00050041,0x00000017,0x00000018,0x0000000b,0x00000013,0x0003003e,0x00000018,0x00000016, 0x00050041,0x00000020,0x00000021,0x0000001f,0x0000000d,0x0004003d,0x0000001c,0x00000022, 0x00000021,0x0004003d,0x00000008,0x00000024,0x00000023,0x00050051,0x00000006,0x00000027, 0x00000024,0x00000000,0x00050051,0x00000006,0x00000028,0x00000024,0x00000001,0x00070050, 0x00000007,0x00000029,0x00000027,0x00000028,0x00000025,0x00000026,0x00050091,0x00000007, 0x0000002a,0x00000022,0x00000029,0x00050041,0x00000011,0x0000002b,0x0000001b,0x0000000d, 0x0003003e,0x0000002b,0x0000002a,0x000100fd,0x00010038 }; // glsl_shader.frag, compiled with: // # glslangValidator -V -x -o glsl_shader.frag.u32 glsl_shader.frag /* #version 450 core layout(location = 0) out vec4 fColor; layout(set=0, binding=1) uniform sampler s; layout(set=1, binding=0) uniform texture2D t; layout(location = 0) in struct { vec4 Color; vec2 UV; } In; void main() { fColor = In.Color * texture(sampler2D(t, s), In.UV.st); } */ static uint32_t __glsl_shader_frag_spv[] = { 0x07230203,0x00010000,0x00080007,0x00000023,0x00000000,0x00020011,0x00000001,0x0006000b, 0x00000001,0x4c534c47,0x6474732e,0x3035342e,0x00000000,0x0003000e,0x00000000,0x00000001, 0x0007000f,0x00000004,0x00000004,0x6e69616d,0x00000000,0x00000009,0x0000000d,0x00030010, 0x00000004,0x00000007,0x00030003,0x00000002,0x000001c2,0x00040005,0x00000004,0x6e69616d, 0x00000000,0x00040005,0x00000009,0x6c6f4366,0x0000726f,0x00030005,0x0000000b,0x00000000, 0x00050006,0x0000000b,0x00000000,0x6f6c6f43,0x00000072,0x00040006,0x0000000b,0x00000001, 0x00005655,0x00030005,0x0000000d,0x00006e49,0x00030005,0x00000015,0x00000074,0x00030005, 0x00000019,0x00000073,0x00040047,0x00000009,0x0000001e,0x00000000,0x00040047,0x0000000d, 0x0000001e,0x00000000,0x00040047,0x00000015,0x00000022,0x00000001,0x00040047,0x00000015, 0x00000021,0x00000000,0x00040047,0x00000019,0x00000022,0x00000000,0x00040047,0x00000019, 0x00000021,0x00000001,0x00020013,0x00000002,0x00030021,0x00000003,0x00000002,0x00030016, 0x00000006,0x00000020,0x00040017,0x00000007,0x00000006,0x00000004,0x00040020,0x00000008, 0x00000003,0x00000007,0x0004003b,0x00000008,0x00000009,0x00000003,0x00040017,0x0000000a, 0x00000006,0x00000002,0x0004001e,0x0000000b,0x00000007,0x0000000a,0x00040020,0x0000000c, 0x00000001,0x0000000b,0x0004003b,0x0000000c,0x0000000d,0x00000001,0x00040015,0x0000000e, 0x00000020,0x00000001,0x0004002b,0x0000000e,0x0000000f,0x00000000,0x00040020,0x00000010, 0x00000001,0x00000007,0x00090019,0x00000013,0x00000006,0x00000001,0x00000000,0x00000000, 0x00000000,0x00000001,0x00000000,0x00040020,0x00000014,0x00000000,0x00000013,0x0004003b, 0x00000014,0x00000015,0x00000000,0x0002001a,0x00000017,0x00040020,0x00000018,0x00000000, 0x00000017,0x0004003b,0x00000018,0x00000019,0x00000000,0x0003001b,0x0000001b,0x00000013, 0x0004002b,0x0000000e,0x0000001d,0x00000001,0x00040020,0x0000001e,0x00000001,0x0000000a, 0x00050036,0x00000002,0x00000004,0x00000000,0x00000003,0x000200f8,0x00000005,0x00050041, 0x00000010,0x00000011,0x0000000d,0x0000000f,0x0004003d,0x00000007,0x00000012,0x00000011, 0x0004003d,0x00000013,0x00000016,0x00000015,0x0004003d,0x00000017,0x0000001a,0x00000019, 0x00050056,0x0000001b,0x0000001c,0x00000016,0x0000001a,0x00050041,0x0000001e,0x0000001f, 0x0000000d,0x0000001d,0x0004003d,0x0000000a,0x00000020,0x0000001f,0x00050057,0x00000007, 0x00000021,0x0000001c,0x00000020,0x00050085,0x00000007,0x00000022,0x00000012,0x00000021, 0x0003003e,0x00000009,0x00000022,0x000100fd,0x00010038 }; static void SafeRelease(ImDrawIdx*& res) { if (res) delete[] res; res = NULL; } static void SafeRelease(ImDrawVert*& res) { if (res) delete[] res; res = NULL; } static void SafeRelease(WGPUBindGroupLayout& res) { if (res) wgpuBindGroupLayoutRelease(res); res = NULL; } static void SafeRelease(WGPUBindGroup& res) { if (res) wgpuBindGroupRelease(res); res = NULL; } static void SafeRelease(WGPUBuffer& res) { if (res) wgpuBufferRelease(res); res = NULL; } static void SafeRelease(WGPURenderPipeline& res) { if (res) wgpuRenderPipelineRelease(res); res = NULL; } static void SafeRelease(WGPUSampler& res) { if (res) wgpuSamplerRelease(res); res = NULL; } static void SafeRelease(WGPUShaderModule& res) { if (res) wgpuShaderModuleRelease(res); res = NULL; } static void SafeRelease(WGPUTextureView& res) { if (res) wgpuTextureViewRelease(res); res = NULL; } static void SafeRelease(WGPUTexture& res) { if (res) wgpuTextureRelease(res); res = NULL; } static void SafeRelease(RenderResources& res) { SafeRelease(res.FontTexture); SafeRelease(res.FontTextureView); SafeRelease(res.Sampler); SafeRelease(res.Uniforms); SafeRelease(res.CommonBindGroup); SafeRelease(res.ImageBindGroup); SafeRelease(res.ImageBindGroupLayout); }; static void SafeRelease(FrameResources& res) { SafeRelease(res.IndexBuffer); SafeRelease(res.VertexBuffer); SafeRelease(res.IndexBufferHost); SafeRelease(res.VertexBufferHost); } static WGPUProgrammableStageDescriptor ImGui_ImplWGPU_CreateShaderModule(uint32_t* binary_data, uint32_t binary_data_size) { WGPUShaderModuleSPIRVDescriptor spirv_desc = {}; spirv_desc.chain.sType = WGPUSType_ShaderModuleSPIRVDescriptor; spirv_desc.codeSize = binary_data_size; spirv_desc.code = binary_data; WGPUShaderModuleDescriptor desc = {}; desc.nextInChain = reinterpret_cast(&spirv_desc); WGPUProgrammableStageDescriptor stage_desc = {}; stage_desc.module = wgpuDeviceCreateShaderModule(g_wgpuDevice, &desc); stage_desc.entryPoint = "main"; return stage_desc; } static WGPUBindGroup ImGui_ImplWGPU_CreateImageBindGroup(WGPUBindGroupLayout layout, WGPUTextureView texture) { WGPUBindGroupEntry image_bg_entries[] = { { nullptr, 0, 0, 0, 0, 0, texture } }; WGPUBindGroupDescriptor image_bg_descriptor = {}; image_bg_descriptor.layout = layout; image_bg_descriptor.entryCount = sizeof(image_bg_entries) / sizeof(WGPUBindGroupEntry); image_bg_descriptor.entries = image_bg_entries; return wgpuDeviceCreateBindGroup(g_wgpuDevice, &image_bg_descriptor); } static void ImGui_ImplWGPU_SetupRenderState(ImDrawData* draw_data, WGPURenderPassEncoder ctx, FrameResources* fr) { // Setup orthographic projection matrix into our constant buffer // Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right). { float L = draw_data->DisplayPos.x; float R = draw_data->DisplayPos.x + draw_data->DisplaySize.x; float T = draw_data->DisplayPos.y; float B = draw_data->DisplayPos.y + draw_data->DisplaySize.y; float mvp[4][4] = { { 2.0f/(R-L), 0.0f, 0.0f, 0.0f }, { 0.0f, 2.0f/(T-B), 0.0f, 0.0f }, { 0.0f, 0.0f, 0.5f, 0.0f }, { (R+L)/(L-R), (T+B)/(B-T), 0.5f, 1.0f }, }; wgpuQueueWriteBuffer(g_defaultQueue, g_resources.Uniforms, 0, mvp, sizeof(mvp)); } // Setup viewport wgpuRenderPassEncoderSetViewport(ctx, 0, 0, draw_data->FramebufferScale.x * draw_data->DisplaySize.x, draw_data->FramebufferScale.y * draw_data->DisplaySize.y, 0, 1); // Bind shader and vertex buffers wgpuRenderPassEncoderSetVertexBuffer(ctx, 0, fr->VertexBuffer, 0, fr->VertexBufferSize * sizeof(ImDrawVert)); wgpuRenderPassEncoderSetIndexBuffer(ctx, fr->IndexBuffer, sizeof(ImDrawIdx) == 2 ? WGPUIndexFormat_Uint16 : WGPUIndexFormat_Uint32, 0, fr->IndexBufferSize * sizeof(ImDrawIdx)); wgpuRenderPassEncoderSetPipeline(ctx, g_pipelineState); wgpuRenderPassEncoderSetBindGroup(ctx, 0, g_resources.CommonBindGroup, 0, NULL); // Setup blend factor WGPUColor blend_color = { 0.f, 0.f, 0.f, 0.f }; wgpuRenderPassEncoderSetBlendConstant(ctx, &blend_color); } // Render function // (this used to be set in io.RenderDrawListsFn and called by ImGui::Render(), but you can now call this directly from your main loop) void ImGui_ImplWGPU_RenderDrawData(ImDrawData* draw_data, WGPURenderPassEncoder pass_encoder) { // Avoid rendering when minimized if (draw_data->DisplaySize.x <= 0.0f || draw_data->DisplaySize.y <= 0.0f) return; // FIXME: Assuming that this only gets called once per frame! // If not, we can't just re-allocate the IB or VB, we'll have to do a proper allocator. g_frameIndex = g_frameIndex + 1; FrameResources* fr = &g_pFrameResources[g_frameIndex % g_numFramesInFlight]; // Create and grow vertex/index buffers if needed if (fr->VertexBuffer == NULL || fr->VertexBufferSize < draw_data->TotalVtxCount) { if (fr->VertexBuffer) { wgpuBufferDestroy(fr->VertexBuffer); wgpuBufferRelease(fr->VertexBuffer); } SafeRelease(fr->VertexBufferHost); fr->VertexBufferSize = draw_data->TotalVtxCount + 5000; WGPUBufferDescriptor vb_desc = { NULL, "Dear ImGui Vertex buffer", WGPUBufferUsage_CopyDst | WGPUBufferUsage_Vertex, fr->VertexBufferSize * sizeof(ImDrawVert), false }; fr->VertexBuffer = wgpuDeviceCreateBuffer(g_wgpuDevice, &vb_desc); if (!fr->VertexBuffer) return; fr->VertexBufferHost = new ImDrawVert[fr->VertexBufferSize]; } if (fr->IndexBuffer == NULL || fr->IndexBufferSize < draw_data->TotalIdxCount) { if (fr->IndexBuffer) { wgpuBufferDestroy(fr->IndexBuffer); wgpuBufferRelease(fr->IndexBuffer); } SafeRelease(fr->IndexBufferHost); fr->IndexBufferSize = draw_data->TotalIdxCount + 10000; WGPUBufferDescriptor ib_desc = { NULL, "Dear ImGui Index buffer", WGPUBufferUsage_CopyDst | WGPUBufferUsage_Index, fr->IndexBufferSize * sizeof(ImDrawIdx), false }; fr->IndexBuffer = wgpuDeviceCreateBuffer(g_wgpuDevice, &ib_desc); if (!fr->IndexBuffer) return; fr->IndexBufferHost = new ImDrawIdx[fr->IndexBufferSize]; } // Upload vertex/index data into a single contiguous GPU buffer ImDrawVert* vtx_dst = (ImDrawVert*)fr->VertexBufferHost; ImDrawIdx* idx_dst = (ImDrawIdx*)fr->IndexBufferHost; for (int n = 0; n < draw_data->CmdListsCount; n++) { const ImDrawList* cmd_list = draw_data->CmdLists[n]; memcpy(vtx_dst, cmd_list->VtxBuffer.Data, cmd_list->VtxBuffer.Size * sizeof(ImDrawVert)); memcpy(idx_dst, cmd_list->IdxBuffer.Data, cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx)); vtx_dst += cmd_list->VtxBuffer.Size; idx_dst += cmd_list->IdxBuffer.Size; } int64_t vb_write_size = ((char*)vtx_dst - (char*)fr->VertexBufferHost + 3) & ~3; int64_t ib_write_size = ((char*)idx_dst - (char*)fr->IndexBufferHost + 3) & ~3; wgpuQueueWriteBuffer(g_defaultQueue, fr->VertexBuffer, 0, fr->VertexBufferHost, vb_write_size); wgpuQueueWriteBuffer(g_defaultQueue, fr->IndexBuffer, 0, fr->IndexBufferHost, ib_write_size); // Setup desired render state ImGui_ImplWGPU_SetupRenderState(draw_data, pass_encoder, fr); // Render command lists // (Because we merged all buffers into a single one, we maintain our own offset into them) int global_vtx_offset = 0; int global_idx_offset = 0; ImVec2 clip_scale = draw_data->FramebufferScale; ImVec2 clip_off = draw_data->DisplayPos; for (int n = 0; n < draw_data->CmdListsCount; n++) { const ImDrawList* cmd_list = draw_data->CmdLists[n]; for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++) { const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i]; if (pcmd->UserCallback != NULL) { // User callback, registered via ImDrawList::AddCallback() // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.) if (pcmd->UserCallback == ImDrawCallback_ResetRenderState) ImGui_ImplWGPU_SetupRenderState(draw_data, pass_encoder, fr); else pcmd->UserCallback(cmd_list, pcmd); } else { // Bind custom texture ImTextureID tex_id = pcmd->GetTexID(); ImGuiID tex_id_hash = ImHashData(&tex_id, sizeof(tex_id)); auto bind_group = g_resources.ImageBindGroups.GetVoidPtr(tex_id_hash); if (bind_group) { wgpuRenderPassEncoderSetBindGroup(pass_encoder, 1, (WGPUBindGroup)bind_group, 0, NULL); } else { WGPUBindGroup image_bind_group = ImGui_ImplWGPU_CreateImageBindGroup(g_resources.ImageBindGroupLayout, (WGPUTextureView)tex_id); g_resources.ImageBindGroups.SetVoidPtr(tex_id_hash, image_bind_group); wgpuRenderPassEncoderSetBindGroup(pass_encoder, 1, image_bind_group, 0, NULL); } // Project scissor/clipping rectangles into framebuffer space ImVec2 clip_min((pcmd->ClipRect.x - clip_off.x) * clip_scale.x, (pcmd->ClipRect.y - clip_off.y) * clip_scale.y); ImVec2 clip_max((pcmd->ClipRect.z - clip_off.x) * clip_scale.x, (pcmd->ClipRect.w - clip_off.y) * clip_scale.y); if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y) continue; // Apply scissor/clipping rectangle, Draw wgpuRenderPassEncoderSetScissorRect(pass_encoder, (uint32_t)clip_min.x, (uint32_t)clip_min.y, (uint32_t)(clip_max.x - clip_min.x), (uint32_t)(clip_max.y - clip_min.y)); wgpuRenderPassEncoderDrawIndexed(pass_encoder, pcmd->ElemCount, 1, pcmd->IdxOffset + global_idx_offset, pcmd->VtxOffset + global_vtx_offset, 0); } } global_idx_offset += cmd_list->IdxBuffer.Size; global_vtx_offset += cmd_list->VtxBuffer.Size; } } static void ImGui_ImplWGPU_CreateFontsTexture() { // Build texture atlas ImGuiIO& io = ImGui::GetIO(); unsigned char* pixels; int width, height, size_pp; io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height, &size_pp); // Upload texture to graphics system { WGPUTextureDescriptor tex_desc = {}; tex_desc.label = "Dear ImGui Font Texture"; tex_desc.dimension = WGPUTextureDimension_2D; tex_desc.size.width = width; tex_desc.size.height = height; tex_desc.size.depthOrArrayLayers = 1; tex_desc.sampleCount = 1; tex_desc.format = WGPUTextureFormat_RGBA8Unorm; tex_desc.mipLevelCount = 1; tex_desc.usage = WGPUTextureUsage_CopyDst | WGPUTextureUsage_TextureBinding; g_resources.FontTexture = wgpuDeviceCreateTexture(g_wgpuDevice, &tex_desc); WGPUTextureViewDescriptor tex_view_desc = {}; tex_view_desc.format = WGPUTextureFormat_RGBA8Unorm; tex_view_desc.dimension = WGPUTextureViewDimension_2D; tex_view_desc.baseMipLevel = 0; tex_view_desc.mipLevelCount = 1; tex_view_desc.baseArrayLayer = 0; tex_view_desc.arrayLayerCount = 1; tex_view_desc.aspect = WGPUTextureAspect_All; g_resources.FontTextureView = wgpuTextureCreateView(g_resources.FontTexture, &tex_view_desc); } // Upload texture data { WGPUImageCopyTexture dst_view = {}; dst_view.texture = g_resources.FontTexture; dst_view.mipLevel = 0; dst_view.origin = { 0, 0, 0 }; dst_view.aspect = WGPUTextureAspect_All; WGPUTextureDataLayout layout = {}; layout.offset = 0; layout.bytesPerRow = width * size_pp; layout.rowsPerImage = height; WGPUExtent3D size = { (uint32_t)width, (uint32_t)height, 1 }; wgpuQueueWriteTexture(g_defaultQueue, &dst_view, pixels, (uint32_t)(width * size_pp * height), &layout, &size); } // Create the associated sampler // (Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling) { WGPUSamplerDescriptor sampler_desc = {}; sampler_desc.minFilter = WGPUFilterMode_Linear; sampler_desc.magFilter = WGPUFilterMode_Linear; sampler_desc.mipmapFilter = WGPUFilterMode_Linear; sampler_desc.addressModeU = WGPUAddressMode_Repeat; sampler_desc.addressModeV = WGPUAddressMode_Repeat; sampler_desc.addressModeW = WGPUAddressMode_Repeat; sampler_desc.maxAnisotropy = 1; g_resources.Sampler = wgpuDeviceCreateSampler(g_wgpuDevice, &sampler_desc); } // Store our identifier static_assert(sizeof(ImTextureID) >= sizeof(g_resources.FontTexture), "Can't pack descriptor handle into TexID, 32-bit not supported yet."); io.Fonts->SetTexID((ImTextureID)g_resources.FontTextureView); } static void ImGui_ImplWGPU_CreateUniformBuffer() { WGPUBufferDescriptor ub_desc = { NULL, "Dear ImGui Uniform buffer", WGPUBufferUsage_CopyDst | WGPUBufferUsage_Uniform, sizeof(Uniforms), false }; g_resources.Uniforms = wgpuDeviceCreateBuffer(g_wgpuDevice, &ub_desc); } bool ImGui_ImplWGPU_CreateDeviceObjects() { if (!g_wgpuDevice) return false; if (g_pipelineState) ImGui_ImplWGPU_InvalidateDeviceObjects(); // Create render pipeline WGPURenderPipelineDescriptor graphics_pipeline_desc = {}; graphics_pipeline_desc.primitive.topology = WGPUPrimitiveTopology_TriangleList; graphics_pipeline_desc.primitive.stripIndexFormat = WGPUIndexFormat_Undefined; graphics_pipeline_desc.primitive.frontFace = WGPUFrontFace_CW; graphics_pipeline_desc.primitive.cullMode = WGPUCullMode_None; graphics_pipeline_desc.multisample.count = 1; graphics_pipeline_desc.multisample.mask = UINT_MAX; graphics_pipeline_desc.multisample.alphaToCoverageEnabled = false; graphics_pipeline_desc.layout = nullptr; // Use automatic layout generation // Create the vertex shader WGPUProgrammableStageDescriptor vertex_shader_desc = ImGui_ImplWGPU_CreateShaderModule(__glsl_shader_vert_spv, sizeof(__glsl_shader_vert_spv) / sizeof(uint32_t)); graphics_pipeline_desc.vertex.module = vertex_shader_desc.module; graphics_pipeline_desc.vertex.entryPoint = vertex_shader_desc.entryPoint; // Vertex input configuration WGPUVertexAttribute attribute_desc[] = { { WGPUVertexFormat_Float32x2, (uint64_t)IM_OFFSETOF(ImDrawVert, pos), 0 }, { WGPUVertexFormat_Float32x2, (uint64_t)IM_OFFSETOF(ImDrawVert, uv), 1 }, { WGPUVertexFormat_Unorm8x4, (uint64_t)IM_OFFSETOF(ImDrawVert, col), 2 }, }; WGPUVertexBufferLayout buffer_layouts[1]; buffer_layouts[0].arrayStride = sizeof(ImDrawVert); buffer_layouts[0].stepMode = WGPUVertexStepMode_Vertex; buffer_layouts[0].attributeCount = 3; buffer_layouts[0].attributes = attribute_desc; graphics_pipeline_desc.vertex.bufferCount = 1; graphics_pipeline_desc.vertex.buffers = buffer_layouts; // Create the pixel shader WGPUProgrammableStageDescriptor pixel_shader_desc = ImGui_ImplWGPU_CreateShaderModule(__glsl_shader_frag_spv, sizeof(__glsl_shader_frag_spv) / sizeof(uint32_t)); // Create the blending setup WGPUBlendState blend_state = {}; blend_state.alpha.operation = WGPUBlendOperation_Add; blend_state.alpha.srcFactor = WGPUBlendFactor_One; blend_state.alpha.dstFactor = WGPUBlendFactor_OneMinusSrcAlpha; blend_state.color.operation = WGPUBlendOperation_Add; blend_state.color.srcFactor = WGPUBlendFactor_SrcAlpha; blend_state.color.dstFactor = WGPUBlendFactor_OneMinusSrcAlpha; WGPUColorTargetState color_state = {}; color_state.format = g_renderTargetFormat; color_state.blend = &blend_state; color_state.writeMask = WGPUColorWriteMask_All; WGPUFragmentState fragment_state = {}; fragment_state.module = pixel_shader_desc.module; fragment_state.entryPoint = pixel_shader_desc.entryPoint; fragment_state.targetCount = 1; fragment_state.targets = &color_state; graphics_pipeline_desc.fragment = &fragment_state; // Create depth-stencil State WGPUDepthStencilState depth_stencil_state = {}; depth_stencil_state.depthBias = 0; depth_stencil_state.depthBiasClamp = 0; depth_stencil_state.depthBiasSlopeScale = 0; // Configure disabled depth-stencil state graphics_pipeline_desc.depthStencil = nullptr; g_pipelineState = wgpuDeviceCreateRenderPipeline(g_wgpuDevice, &graphics_pipeline_desc); ImGui_ImplWGPU_CreateFontsTexture(); ImGui_ImplWGPU_CreateUniformBuffer(); // Create resource bind group WGPUBindGroupLayout bg_layouts[2]; bg_layouts[0] = wgpuRenderPipelineGetBindGroupLayout(g_pipelineState, 0); bg_layouts[1] = wgpuRenderPipelineGetBindGroupLayout(g_pipelineState, 1); WGPUBindGroupEntry common_bg_entries[] = { { nullptr, 0, g_resources.Uniforms, 0, sizeof(Uniforms), 0, 0 }, { nullptr, 1, 0, 0, 0, g_resources.Sampler, 0 }, }; WGPUBindGroupDescriptor common_bg_descriptor = {}; common_bg_descriptor.layout = bg_layouts[0]; common_bg_descriptor.entryCount = sizeof(common_bg_entries) / sizeof(WGPUBindGroupEntry); common_bg_descriptor.entries = common_bg_entries; g_resources.CommonBindGroup = wgpuDeviceCreateBindGroup(g_wgpuDevice, &common_bg_descriptor); WGPUBindGroup image_bind_group = ImGui_ImplWGPU_CreateImageBindGroup(bg_layouts[1], g_resources.FontTextureView); g_resources.ImageBindGroup = image_bind_group; g_resources.ImageBindGroupLayout = bg_layouts[1]; g_resources.ImageBindGroups.SetVoidPtr(ImHashData(&g_resources.FontTextureView, sizeof(ImTextureID)), image_bind_group); SafeRelease(vertex_shader_desc.module); SafeRelease(pixel_shader_desc.module); SafeRelease(bg_layouts[0]); return true; } void ImGui_ImplWGPU_InvalidateDeviceObjects() { if (!g_wgpuDevice) return; SafeRelease(g_pipelineState); SafeRelease(g_resources); ImGuiIO& io = ImGui::GetIO(); io.Fonts->SetTexID(NULL); // We copied g_pFontTextureView to io.Fonts->TexID so let's clear that as well. for (unsigned int i = 0; i < g_numFramesInFlight; i++) SafeRelease(g_pFrameResources[i]); } bool ImGui_ImplWGPU_Init(WGPUDevice device, int num_frames_in_flight, WGPUTextureFormat rt_format) { // Setup backend capabilities flags ImGuiIO& io = ImGui::GetIO(); io.BackendRendererName = "imgui_impl_webgpu"; io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset; // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes. g_wgpuDevice = device; g_defaultQueue = wgpuDeviceGetQueue(g_wgpuDevice); g_renderTargetFormat = rt_format; g_pFrameResources = new FrameResources[num_frames_in_flight]; g_numFramesInFlight = num_frames_in_flight; g_frameIndex = UINT_MAX; g_resources.FontTexture = NULL; g_resources.FontTextureView = NULL; g_resources.Sampler = NULL; g_resources.Uniforms = NULL; g_resources.CommonBindGroup = NULL; g_resources.ImageBindGroups.Data.reserve(100); g_resources.ImageBindGroup = NULL; g_resources.ImageBindGroupLayout = NULL; // Create buffers with a default size (they will later be grown as needed) for (int i = 0; i < num_frames_in_flight; i++) { FrameResources* fr = &g_pFrameResources[i]; fr->IndexBuffer = NULL; fr->VertexBuffer = NULL; fr->IndexBufferHost = NULL; fr->VertexBufferHost = NULL; fr->IndexBufferSize = 10000; fr->VertexBufferSize = 5000; } return true; } void ImGui_ImplWGPU_Shutdown() { ImGui_ImplWGPU_InvalidateDeviceObjects(); delete[] g_pFrameResources; g_pFrameResources = NULL; wgpuQueueRelease(g_defaultQueue); g_wgpuDevice = NULL; g_numFramesInFlight = 0; g_frameIndex = UINT_MAX; } void ImGui_ImplWGPU_NewFrame() { if (!g_pipelineState) ImGui_ImplWGPU_CreateDeviceObjects(); }