diff options
Diffstat (limited to 'src/imgui/backends/imgui_impl_wgpu.cpp')
| -rw-r--r-- | src/imgui/backends/imgui_impl_wgpu.cpp | 780 |
1 files changed, 780 insertions, 0 deletions
diff --git a/src/imgui/backends/imgui_impl_wgpu.cpp b/src/imgui/backends/imgui_impl_wgpu.cpp new file mode 100644 index 0000000..638e9fd --- /dev/null +++ b/src/imgui/backends/imgui_impl_wgpu.cpp @@ -0,0 +1,780 @@ +// 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. +// 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 + +// CHANGELOG +// (minor and older changes stripped away, please see git history for details) +// 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). +// 2023-01-25: Revert automatic pipeline layout generation (see https://github.com/gpuweb/gpuweb/issues/2470) +// 2022-11-24: Fixed validation error with default depth buffer settings. +// 2022-11-10: Fixed rendering when a depth buffer is enabled. Added 'WGPUTextureFormat depth_format' parameter to ImGui_ImplWGPU_Init(). +// 2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11. +// 2021-11-29: Passing explicit buffer sizes to wgpuRenderPassEncoderSetVertexBuffer()/wgpuRenderPassEncoderSetIndexBuffer(). +// 2021-08-24: Fixed 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" +#ifndef IMGUI_DISABLE +#include "imgui_impl_wgpu.h" +#include <limits.h> +#include <webgpu/webgpu.h> + +// Dear ImGui prototypes from imgui_internal.h +extern ImGuiID ImHashData(const void* data_p, size_t data_size, ImU32 seed = 0); +#define MEMALIGN(_SIZE,_ALIGN) (((_SIZE) + ((_ALIGN) - 1)) & ~((_ALIGN) - 1)) // Memory align (copied from IM_ALIGN() macro). + +// WebGPU data +struct RenderResources +{ + WGPUTexture FontTexture = nullptr; // Font texture + WGPUTextureView FontTextureView = nullptr; // Texture view for font texture + WGPUSampler Sampler = nullptr; // Sampler for the font texture + WGPUBuffer Uniforms = nullptr; // Shader uniforms + WGPUBindGroup CommonBindGroup = nullptr; // 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 = nullptr; // Default font-resource of Dear ImGui + WGPUBindGroupLayout ImageBindGroupLayout = nullptr; // Cache layout used for the image bind group. Avoids allocating unnecessary JS objects when working with WebASM +}; + +struct FrameResources +{ + WGPUBuffer IndexBuffer; + WGPUBuffer VertexBuffer; + ImDrawIdx* IndexBufferHost; + ImDrawVert* VertexBufferHost; + int IndexBufferSize; + int VertexBufferSize; +}; + +struct Uniforms +{ + float MVP[4][4]; + float Gamma; +}; + +struct ImGui_ImplWGPU_Data +{ + WGPUDevice wgpuDevice = nullptr; + WGPUQueue defaultQueue = nullptr; + WGPUTextureFormat renderTargetFormat = WGPUTextureFormat_Undefined; + WGPUTextureFormat depthStencilFormat = WGPUTextureFormat_Undefined; + WGPURenderPipeline pipelineState = nullptr; + + RenderResources renderResources; + FrameResources* pFrameResources = nullptr; + unsigned int numFramesInFlight = 0; + unsigned int frameIndex = UINT_MAX; +}; + +// Backend data stored in io.BackendRendererUserData to allow support for multiple Dear ImGui contexts +// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts. +static ImGui_ImplWGPU_Data* ImGui_ImplWGPU_GetBackendData() +{ + return ImGui::GetCurrentContext() ? (ImGui_ImplWGPU_Data*)ImGui::GetIO().BackendRendererUserData : nullptr; +} + +//----------------------------------------------------------------------------- +// SHADERS +//----------------------------------------------------------------------------- + +static const char __shader_vert_wgsl[] = R"( +struct VertexInput { + @location(0) position: vec2<f32>, + @location(1) uv: vec2<f32>, + @location(2) color: vec4<f32>, +}; + +struct VertexOutput { + @builtin(position) position: vec4<f32>, + @location(0) color: vec4<f32>, + @location(1) uv: vec2<f32>, +}; + +struct Uniforms { + mvp: mat4x4<f32>, + gamma: f32, +}; + +@group(0) @binding(0) var<uniform> uniforms: Uniforms; + +@vertex +fn main(in: VertexInput) -> VertexOutput { + var out: VertexOutput; + out.position = uniforms.mvp * vec4<f32>(in.position, 0.0, 1.0); + out.color = in.color; + out.uv = in.uv; + return out; +} +)"; + +static const char __shader_frag_wgsl[] = R"( +struct VertexOutput { + @builtin(position) position: vec4<f32>, + @location(0) color: vec4<f32>, + @location(1) uv: vec2<f32>, +}; + +struct Uniforms { + mvp: mat4x4<f32>, + gamma: f32, +}; + +@group(0) @binding(0) var<uniform> uniforms: Uniforms; +@group(0) @binding(1) var s: sampler; +@group(1) @binding(0) var t: texture_2d<f32>; + +@fragment +fn main(in: VertexOutput) -> @location(0) vec4<f32> { + let color = in.color * textureSample(t, s, in.uv); + let corrected_color = pow(color.rgb, vec3<f32>(uniforms.gamma)); + return vec4<f32>(corrected_color, color.a); +} +)"; + +static void SafeRelease(ImDrawIdx*& res) +{ + if (res) + delete[] res; + res = nullptr; +} +static void SafeRelease(ImDrawVert*& res) +{ + if (res) + delete[] res; + res = nullptr; +} +static void SafeRelease(WGPUBindGroupLayout& res) +{ + if (res) + wgpuBindGroupLayoutRelease(res); + res = nullptr; +} +static void SafeRelease(WGPUBindGroup& res) +{ + if (res) + wgpuBindGroupRelease(res); + res = nullptr; +} +static void SafeRelease(WGPUBuffer& res) +{ + if (res) + wgpuBufferRelease(res); + res = nullptr; +} +static void SafeRelease(WGPURenderPipeline& res) +{ + if (res) + wgpuRenderPipelineRelease(res); + res = nullptr; +} +static void SafeRelease(WGPUSampler& res) +{ + if (res) + wgpuSamplerRelease(res); + res = nullptr; +} +static void SafeRelease(WGPUShaderModule& res) +{ + if (res) + wgpuShaderModuleRelease(res); + res = nullptr; +} +static void SafeRelease(WGPUTextureView& res) +{ + if (res) + wgpuTextureViewRelease(res); + res = nullptr; +} +static void SafeRelease(WGPUTexture& res) +{ + if (res) + wgpuTextureRelease(res); + res = nullptr; +} + +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(const char* wgsl_source) +{ + ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData(); + + WGPUShaderModuleWGSLDescriptor wgsl_desc = {}; + wgsl_desc.chain.sType = WGPUSType_ShaderModuleWGSLDescriptor; + wgsl_desc.code = wgsl_source; + + WGPUShaderModuleDescriptor desc = {}; + desc.nextInChain = reinterpret_cast<WGPUChainedStruct*>(&wgsl_desc); + + WGPUProgrammableStageDescriptor stage_desc = {}; + stage_desc.module = wgpuDeviceCreateShaderModule(bd->wgpuDevice, &desc); + stage_desc.entryPoint = "main"; + return stage_desc; +} + +static WGPUBindGroup ImGui_ImplWGPU_CreateImageBindGroup(WGPUBindGroupLayout layout, WGPUTextureView texture) +{ + ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData(); + 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(bd->wgpuDevice, &image_bg_descriptor); +} + +static void ImGui_ImplWGPU_SetupRenderState(ImDrawData* draw_data, WGPURenderPassEncoder ctx, FrameResources* fr) +{ + ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData(); + + // 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(bd->defaultQueue, bd->renderResources.Uniforms, offsetof(Uniforms, MVP), mvp, sizeof(Uniforms::MVP)); + float gamma; + switch (bd->renderTargetFormat) + { + case WGPUTextureFormat_ASTC10x10UnormSrgb: + case WGPUTextureFormat_ASTC10x5UnormSrgb: + case WGPUTextureFormat_ASTC10x6UnormSrgb: + case WGPUTextureFormat_ASTC10x8UnormSrgb: + case WGPUTextureFormat_ASTC12x10UnormSrgb: + case WGPUTextureFormat_ASTC12x12UnormSrgb: + case WGPUTextureFormat_ASTC4x4UnormSrgb: + case WGPUTextureFormat_ASTC5x5UnormSrgb: + case WGPUTextureFormat_ASTC6x5UnormSrgb: + case WGPUTextureFormat_ASTC6x6UnormSrgb: + case WGPUTextureFormat_ASTC8x5UnormSrgb: + case WGPUTextureFormat_ASTC8x6UnormSrgb: + case WGPUTextureFormat_ASTC8x8UnormSrgb: + case WGPUTextureFormat_BC1RGBAUnormSrgb: + case WGPUTextureFormat_BC2RGBAUnormSrgb: + case WGPUTextureFormat_BC3RGBAUnormSrgb: + case WGPUTextureFormat_BC7RGBAUnormSrgb: + case WGPUTextureFormat_BGRA8UnormSrgb: + case WGPUTextureFormat_ETC2RGB8A1UnormSrgb: + case WGPUTextureFormat_ETC2RGB8UnormSrgb: + case WGPUTextureFormat_ETC2RGBA8UnormSrgb: + case WGPUTextureFormat_RGBA8UnormSrgb: + gamma = 2.2f; + break; + default: + gamma = 1.0f; + } + wgpuQueueWriteBuffer(bd->defaultQueue, bd->renderResources.Uniforms, offsetof(Uniforms, Gamma), &gamma, sizeof(Uniforms::Gamma)); + } + + // 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, bd->pipelineState); + wgpuRenderPassEncoderSetBindGroup(ctx, 0, bd->renderResources.CommonBindGroup, 0, nullptr); + + // 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 + int fb_width = (int)(draw_data->DisplaySize.x * draw_data->FramebufferScale.x); + int fb_height = (int)(draw_data->DisplaySize.y * draw_data->FramebufferScale.y); + if (fb_width <= 0 || fb_height <= 0 || draw_data->CmdListsCount == 0) + 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. + ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData(); + bd->frameIndex = bd->frameIndex + 1; + FrameResources* fr = &bd->pFrameResources[bd->frameIndex % bd->numFramesInFlight]; + + // Create and grow vertex/index buffers if needed + if (fr->VertexBuffer == nullptr || 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 = + { + nullptr, + "Dear ImGui Vertex buffer", + WGPUBufferUsage_CopyDst | WGPUBufferUsage_Vertex, + MEMALIGN(fr->VertexBufferSize * sizeof(ImDrawVert), 4), + false + }; + fr->VertexBuffer = wgpuDeviceCreateBuffer(bd->wgpuDevice, &vb_desc); + if (!fr->VertexBuffer) + return; + + fr->VertexBufferHost = new ImDrawVert[fr->VertexBufferSize]; + } + if (fr->IndexBuffer == nullptr || 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 = + { + nullptr, + "Dear ImGui Index buffer", + WGPUBufferUsage_CopyDst | WGPUBufferUsage_Index, + MEMALIGN(fr->IndexBufferSize * sizeof(ImDrawIdx), 4), + false + }; + fr->IndexBuffer = wgpuDeviceCreateBuffer(bd->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 = MEMALIGN((char*)vtx_dst - (char*)fr->VertexBufferHost, 4); + int64_t ib_write_size = MEMALIGN((char*)idx_dst - (char*)fr->IndexBufferHost, 4); + wgpuQueueWriteBuffer(bd->defaultQueue, fr->VertexBuffer, 0, fr->VertexBufferHost, vb_write_size); + wgpuQueueWriteBuffer(bd->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 != nullptr) + { + // 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 = bd->renderResources.ImageBindGroups.GetVoidPtr(tex_id_hash); + if (bind_group) + { + wgpuRenderPassEncoderSetBindGroup(pass_encoder, 1, (WGPUBindGroup)bind_group, 0, nullptr); + } + else + { + WGPUBindGroup image_bind_group = ImGui_ImplWGPU_CreateImageBindGroup(bd->renderResources.ImageBindGroupLayout, (WGPUTextureView)tex_id); + bd->renderResources.ImageBindGroups.SetVoidPtr(tex_id_hash, image_bind_group); + wgpuRenderPassEncoderSetBindGroup(pass_encoder, 1, image_bind_group, 0, nullptr); + } + + // 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); + + // Clamp to viewport as wgpuRenderPassEncoderSetScissorRect() won't accept values that are off bounds + if (clip_min.x < 0.0f) { clip_min.x = 0.0f; } + if (clip_min.y < 0.0f) { clip_min.y = 0.0f; } + if (clip_max.x > fb_width) { clip_max.x = (float)fb_width; } + if (clip_max.y > fb_height) { clip_max.y = (float)fb_height; } + 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 + ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData(); + 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; + bd->renderResources.FontTexture = wgpuDeviceCreateTexture(bd->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; + bd->renderResources.FontTextureView = wgpuTextureCreateView(bd->renderResources.FontTexture, &tex_view_desc); + } + + // Upload texture data + { + WGPUImageCopyTexture dst_view = {}; + dst_view.texture = bd->renderResources.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(bd->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 = WGPUMipmapFilterMode_Linear; + sampler_desc.addressModeU = WGPUAddressMode_Repeat; + sampler_desc.addressModeV = WGPUAddressMode_Repeat; + sampler_desc.addressModeW = WGPUAddressMode_Repeat; + sampler_desc.maxAnisotropy = 1; + bd->renderResources.Sampler = wgpuDeviceCreateSampler(bd->wgpuDevice, &sampler_desc); + } + + // Store our identifier + static_assert(sizeof(ImTextureID) >= sizeof(bd->renderResources.FontTexture), "Can't pack descriptor handle into TexID, 32-bit not supported yet."); + io.Fonts->SetTexID((ImTextureID)bd->renderResources.FontTextureView); +} + +static void ImGui_ImplWGPU_CreateUniformBuffer() +{ + ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData(); + WGPUBufferDescriptor ub_desc = + { + nullptr, + "Dear ImGui Uniform buffer", + WGPUBufferUsage_CopyDst | WGPUBufferUsage_Uniform, + MEMALIGN(sizeof(Uniforms), 16), + false + }; + bd->renderResources.Uniforms = wgpuDeviceCreateBuffer(bd->wgpuDevice, &ub_desc); +} + +bool ImGui_ImplWGPU_CreateDeviceObjects() +{ + ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData(); + if (!bd->wgpuDevice) + return false; + if (bd->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; + + // Bind group layouts + WGPUBindGroupLayoutEntry common_bg_layout_entries[2] = {}; + common_bg_layout_entries[0].binding = 0; + common_bg_layout_entries[0].visibility = WGPUShaderStage_Vertex | WGPUShaderStage_Fragment; + common_bg_layout_entries[0].buffer.type = WGPUBufferBindingType_Uniform; + common_bg_layout_entries[1].binding = 1; + common_bg_layout_entries[1].visibility = WGPUShaderStage_Fragment; + common_bg_layout_entries[1].sampler.type = WGPUSamplerBindingType_Filtering; + + WGPUBindGroupLayoutEntry image_bg_layout_entries[1] = {}; + image_bg_layout_entries[0].binding = 0; + image_bg_layout_entries[0].visibility = WGPUShaderStage_Fragment; + image_bg_layout_entries[0].texture.sampleType = WGPUTextureSampleType_Float; + image_bg_layout_entries[0].texture.viewDimension = WGPUTextureViewDimension_2D; + + WGPUBindGroupLayoutDescriptor common_bg_layout_desc = {}; + common_bg_layout_desc.entryCount = 2; + common_bg_layout_desc.entries = common_bg_layout_entries; + + WGPUBindGroupLayoutDescriptor image_bg_layout_desc = {}; + image_bg_layout_desc.entryCount = 1; + image_bg_layout_desc.entries = image_bg_layout_entries; + + WGPUBindGroupLayout bg_layouts[2]; + bg_layouts[0] = wgpuDeviceCreateBindGroupLayout(bd->wgpuDevice, &common_bg_layout_desc); + bg_layouts[1] = wgpuDeviceCreateBindGroupLayout(bd->wgpuDevice, &image_bg_layout_desc); + + WGPUPipelineLayoutDescriptor layout_desc = {}; + layout_desc.bindGroupLayoutCount = 2; + layout_desc.bindGroupLayouts = bg_layouts; + graphics_pipeline_desc.layout = wgpuDeviceCreatePipelineLayout(bd->wgpuDevice, &layout_desc); + + // Create the vertex shader + WGPUProgrammableStageDescriptor vertex_shader_desc = ImGui_ImplWGPU_CreateShaderModule(__shader_vert_wgsl); + 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)offsetof(ImDrawVert, pos), 0 }, + { WGPUVertexFormat_Float32x2, (uint64_t)offsetof(ImDrawVert, uv), 1 }, + { WGPUVertexFormat_Unorm8x4, (uint64_t)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(__shader_frag_wgsl); + + // 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 = bd->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.format = bd->depthStencilFormat; + depth_stencil_state.depthWriteEnabled = false; + depth_stencil_state.depthCompare = WGPUCompareFunction_Always; + depth_stencil_state.stencilFront.compare = WGPUCompareFunction_Always; + depth_stencil_state.stencilBack.compare = WGPUCompareFunction_Always; + + // Configure disabled depth-stencil state + graphics_pipeline_desc.depthStencil = (bd->depthStencilFormat == WGPUTextureFormat_Undefined) ? nullptr : &depth_stencil_state; + + bd->pipelineState = wgpuDeviceCreateRenderPipeline(bd->wgpuDevice, &graphics_pipeline_desc); + + ImGui_ImplWGPU_CreateFontsTexture(); + ImGui_ImplWGPU_CreateUniformBuffer(); + + // Create resource bind group + WGPUBindGroupEntry common_bg_entries[] = + { + { nullptr, 0, bd->renderResources.Uniforms, 0, MEMALIGN(sizeof(Uniforms), 16), 0, 0 }, + { nullptr, 1, 0, 0, 0, bd->renderResources.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; + bd->renderResources.CommonBindGroup = wgpuDeviceCreateBindGroup(bd->wgpuDevice, &common_bg_descriptor); + + WGPUBindGroup image_bind_group = ImGui_ImplWGPU_CreateImageBindGroup(bg_layouts[1], bd->renderResources.FontTextureView); + bd->renderResources.ImageBindGroup = image_bind_group; + bd->renderResources.ImageBindGroupLayout = bg_layouts[1]; + bd->renderResources.ImageBindGroups.SetVoidPtr(ImHashData(&bd->renderResources.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() +{ + ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData(); + if (!bd->wgpuDevice) + return; + + SafeRelease(bd->pipelineState); + SafeRelease(bd->renderResources); + + ImGuiIO& io = ImGui::GetIO(); + io.Fonts->SetTexID(0); // We copied g_pFontTextureView to io.Fonts->TexID so let's clear that as well. + + for (unsigned int i = 0; i < bd->numFramesInFlight; i++) + SafeRelease(bd->pFrameResources[i]); +} + +bool ImGui_ImplWGPU_Init(WGPUDevice device, int num_frames_in_flight, WGPUTextureFormat rt_format, WGPUTextureFormat depth_format) +{ + ImGuiIO& io = ImGui::GetIO(); + IM_ASSERT(io.BackendRendererUserData == nullptr && "Already initialized a renderer backend!"); + + // Setup backend capabilities flags + ImGui_ImplWGPU_Data* bd = IM_NEW(ImGui_ImplWGPU_Data)(); + io.BackendRendererUserData = (void*)bd; + io.BackendRendererName = "imgui_impl_webgpu"; + io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset; // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes. + + bd->wgpuDevice = device; + bd->defaultQueue = wgpuDeviceGetQueue(bd->wgpuDevice); + bd->renderTargetFormat = rt_format; + bd->depthStencilFormat = depth_format; + bd->numFramesInFlight = num_frames_in_flight; + bd->frameIndex = UINT_MAX; + + bd->renderResources.FontTexture = nullptr; + bd->renderResources.FontTextureView = nullptr; + bd->renderResources.Sampler = nullptr; + bd->renderResources.Uniforms = nullptr; + bd->renderResources.CommonBindGroup = nullptr; + bd->renderResources.ImageBindGroups.Data.reserve(100); + bd->renderResources.ImageBindGroup = nullptr; + bd->renderResources.ImageBindGroupLayout = nullptr; + + // Create buffers with a default size (they will later be grown as needed) + bd->pFrameResources = new FrameResources[num_frames_in_flight]; + for (int i = 0; i < num_frames_in_flight; i++) + { + FrameResources* fr = &bd->pFrameResources[i]; + fr->IndexBuffer = nullptr; + fr->VertexBuffer = nullptr; + fr->IndexBufferHost = nullptr; + fr->VertexBufferHost = nullptr; + fr->IndexBufferSize = 10000; + fr->VertexBufferSize = 5000; + } + + return true; +} + +void ImGui_ImplWGPU_Shutdown() +{ + ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData(); + IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?"); + ImGuiIO& io = ImGui::GetIO(); + + ImGui_ImplWGPU_InvalidateDeviceObjects(); + delete[] bd->pFrameResources; + bd->pFrameResources = nullptr; + wgpuQueueRelease(bd->defaultQueue); + bd->wgpuDevice = nullptr; + bd->numFramesInFlight = 0; + bd->frameIndex = UINT_MAX; + + io.BackendRendererName = nullptr; + io.BackendRendererUserData = nullptr; + io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset; + IM_DELETE(bd); +} + +void ImGui_ImplWGPU_NewFrame() +{ + ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData(); + if (!bd->pipelineState) + ImGui_ImplWGPU_CreateDeviceObjects(); +} + +//----------------------------------------------------------------------------- + +#endif // #ifndef IMGUI_DISABLE |