imgui/backends/imgui_impl_wgpu.cpp
Elie Michel d81f2ae4fb Backends: WebGPU: Use WGSL shaders instead of precompiled SPIR-V + add Gamma uniform. (#6188)
Add gamma correction uniform
Group uniforms in a single binding
The second binding was not satisfying the minimum
BufferBindingType::Uniform alignment (256) and since this alignment is
large it is more idiomatic to group uniforms tegether.

Also ensures that the size of the uniform buffer is aligned to 16 bytes.
2023-04-11 16:03:26 +02:00

762 lines
31 KiB
C++

// 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)
// 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"
#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.source = 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
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.
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);
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 = WGPUFilterMode_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)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(__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;
IM_DELETE(bd);
}
void ImGui_ImplWGPU_NewFrame()
{
ImGui_ImplWGPU_Data* bd = ImGui_ImplWGPU_GetBackendData();
if (!bd->pipelineState)
ImGui_ImplWGPU_CreateDeviceObjects();
}