src/gpu/graphite/dawn/DawnResourceProvider.cpp - skia - Git at Google

 /*
  * Copyright 2022 Google LLC
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */

 #include "src/gpu/graphite/dawn/DawnResourceProvider.h"

 #include "include/gpu/graphite/BackendTexture.h"
 #include "include/gpu/graphite/TextureInfo.h"
 #include "include/private/base/SkAlign.h"
 #include "src/gpu/graphite/ComputePipeline.h"
 #include "src/gpu/graphite/RenderPassDesc.h"
 #include "src/gpu/graphite/dawn/DawnBuffer.h"
 #include "src/gpu/graphite/dawn/DawnComputePipeline.h"
 #include "src/gpu/graphite/dawn/DawnErrorChecker.h"
 #include "src/gpu/graphite/dawn/DawnGraphicsPipeline.h"
 #include "src/gpu/graphite/dawn/DawnSampler.h"
 #include "src/gpu/graphite/dawn/DawnSharedContext.h"
 #include "src/gpu/graphite/dawn/DawnTexture.h"
 #include "src/sksl/SkSLCompiler.h"

 namespace skgpu::graphite {

 namespace {

 constexpr int kBufferBindingSizeAlignment = 16;
 constexpr int kMaxNumberOfCachedBufferBindGroups = 32;
 constexpr int kMaxNumberOfCachedTextureBindGroups = 4096;

 wgpu::ShaderModule create_shader_module(const wgpu::Device& device, const char* source) {
     wgpu::ShaderModuleWGSLDescriptor wgslDesc;
     wgslDesc.code = source;
     wgpu::ShaderModuleDescriptor descriptor;
     descriptor.nextInChain = &wgslDesc;
     return device.CreateShaderModule(&descriptor);
 }

 wgpu::RenderPipeline create_blit_render_pipeline(const DawnSharedContext* sharedContext,
                                                  const char* label,
                                                  wgpu::ShaderModule vsModule,
                                                  wgpu::ShaderModule fsModule,
                                                  wgpu::TextureFormat renderPassColorFormat,
                                                  wgpu::TextureFormat renderPassDepthStencilFormat,
                                                  int numSamples) {
     wgpu::RenderPipelineDescriptor descriptor;
     descriptor.label = label;
     descriptor.layout = nullptr;

     wgpu::ColorTargetState colorTarget;
     colorTarget.format = renderPassColorFormat;
     colorTarget.blend = nullptr;
     colorTarget.writeMask = wgpu::ColorWriteMask::All;

     wgpu::DepthStencilState depthStencil;
     if (renderPassDepthStencilFormat != wgpu::TextureFormat::Undefined) {
         depthStencil.format = renderPassDepthStencilFormat;
         depthStencil.depthWriteEnabled = false;
         depthStencil.depthCompare = wgpu::CompareFunction::Always;

         descriptor.depthStencil = &depthStencil;
     }

     wgpu::FragmentState fragment;
     fragment.module = std::move(fsModule);
     fragment.entryPoint = "main";
     fragment.targetCount = 1;
     fragment.targets = &colorTarget;
     descriptor.fragment = &fragment;

     descriptor.vertex.module = std::move(vsModule);
     descriptor.vertex.entryPoint = "main";
     descriptor.vertex.constantCount = 0;
     descriptor.vertex.constants = nullptr;
     descriptor.vertex.bufferCount = 0;
     descriptor.vertex.buffers = nullptr;

     descriptor.primitive.frontFace = wgpu::FrontFace::CCW;
     descriptor.primitive.cullMode = wgpu::CullMode::None;
     descriptor.primitive.topology = wgpu::PrimitiveTopology::TriangleStrip;
     descriptor.primitive.stripIndexFormat = wgpu::IndexFormat::Undefined;

     descriptor.multisample.count = numSamples;
     descriptor.multisample.mask = 0xFFFFFFFF;
     descriptor.multisample.alphaToCoverageEnabled = false;

     std::optional<DawnErrorChecker> errorChecker;
     if (sharedContext->dawnCaps()->allowScopedErrorChecks()) {
         errorChecker.emplace(sharedContext);
     }
     auto pipeline = sharedContext->device().CreateRenderPipeline(&descriptor);
     if (errorChecker.has_value() && errorChecker->popErrorScopes() != DawnErrorType::kNoError) {
         return nullptr;
     }

     return pipeline;
 }

 UniqueKey make_ubo_bind_group_key(
         const std::array<std::pair<const DawnBuffer*, uint32_t>, 3>& boundBuffersAndSizes) {
     static const UniqueKey::Domain kBufferBindGroupDomain = UniqueKey::GenerateDomain();

     UniqueKey uniqueKey;
     {
         // Each entry in the bind group needs 2 uint32_t in the key:
         //  - buffer's unique ID: 32 bits.
         //  - buffer's binding size: 32 bits.
         // We need total of 3 entries in the uniform buffer bind group.
         // Unused entries will be assigned zero values.
         UniqueKey::Builder builder(
                 &uniqueKey, kBufferBindGroupDomain, 6, "GraphicsPipelineBufferBindGroup");

         for (uint32_t i = 0; i < boundBuffersAndSizes.size(); ++i) {
             const DawnBuffer* boundBuffer = boundBuffersAndSizes[i].first;
             const uint32_t bindingSize = boundBuffersAndSizes[i].second;
             if (boundBuffer) {
                 builder[2 * i] = boundBuffer->uniqueID().asUInt();
                 builder[2 * i + 1] = bindingSize;
             } else {
                 builder[2 * i] = 0;
                 builder[2 * i + 1] = 0;
             }
         }

         builder.finish();
     }

     return uniqueKey;
 }

 UniqueKey make_texture_bind_group_key(const DawnSampler* sampler, const DawnTexture* texture) {
     static const UniqueKey::Domain kTextureBindGroupDomain = UniqueKey::GenerateDomain();

     UniqueKey uniqueKey;
     {
         UniqueKey::Builder builder(&uniqueKey,
                                    kTextureBindGroupDomain,
                                    2,
                                    "GraphicsPipelineSingleTextureSamplerBindGroup");

         builder[0] = sampler->uniqueID().asUInt();
         builder[1] = texture->uniqueID().asUInt();

         builder.finish();
     }

     return uniqueKey;
 }
 }  // namespace

 DawnResourceProvider::DawnResourceProvider(SharedContext* sharedContext,
                                            SingleOwner* singleOwner,
                                            uint32_t recorderID,
                                            size_t resourceBudget)
         : ResourceProvider(sharedContext, singleOwner, recorderID, resourceBudget)
         , fUniformBufferBindGroupCache(kMaxNumberOfCachedBufferBindGroups)
         , fSingleTextureSamplerBindGroups(kMaxNumberOfCachedTextureBindGroups) {}

 DawnResourceProvider::~DawnResourceProvider() = default;

 wgpu::RenderPipeline DawnResourceProvider::findOrCreateBlitWithDrawPipeline(
         const RenderPassDesc& renderPassDesc) {
     uint64_t renderPassKey =
             this->dawnSharedContext()->dawnCaps()->getRenderPassDescKey(renderPassDesc);
     wgpu::RenderPipeline pipeline = fBlitWithDrawPipelines[renderPassKey];
     if (!pipeline) {
         static constexpr char kVertexShaderText[] = R"(
             var<private> fullscreenTriPositions : array<vec2<f32>, 3> = array<vec2<f32>, 3>(
                 vec2(-1.0, -1.0), vec2(-1.0, 3.0), vec2(3.0, -1.0));

             @vertex
             fn main(@builtin(vertex_index) vertexIndex : u32) -> @builtin(position) vec4<f32> {
                 return vec4(fullscreenTriPositions[vertexIndex], 1.0, 1.0);
             }
         )";

         static constexpr char kFragmentShaderText[] = R"(
             @group(0) @binding(0) var colorMap: texture_2d<f32>;

             @fragment
             fn main(@builtin(position) fragPosition : vec4<f32>) -> @location(0) vec4<f32> {
                 var coords : vec2<i32> = vec2<i32>(i32(fragPosition.x), i32(fragPosition.y));
                 return textureLoad(colorMap, coords, 0);
             }
         )";

         auto vsModule = create_shader_module(dawnSharedContext()->device(), kVertexShaderText);
         auto fsModule = create_shader_module(dawnSharedContext()->device(), kFragmentShaderText);

         pipeline = create_blit_render_pipeline(
                 dawnSharedContext(),
                 /*label=*/"BlitWithDraw",
                 std::move(vsModule),
                 std::move(fsModule),
                 /*renderPassColorFormat=*/
                 renderPassDesc.fColorAttachment.fTextureInfo.dawnTextureSpec().getViewFormat(),
                 /*renderPassDepthStencilFormat=*/
                 renderPassDesc.fDepthStencilAttachment.fTextureInfo.isValid()
                         ? renderPassDesc.fDepthStencilAttachment.fTextureInfo.dawnTextureSpec()
                                   .getViewFormat()
                         : wgpu::TextureFormat::Undefined,
                 /*numSamples=*/renderPassDesc.fColorAttachment.fTextureInfo.numSamples());

         if (pipeline) {
             fBlitWithDrawPipelines.set(renderPassKey, pipeline);
         }
     }

     return pipeline;
 }

 sk_sp<Texture> DawnResourceProvider::onCreateWrappedTexture(const BackendTexture& texture) {
     // Convert to smart pointers. wgpu::Texture* constructor will increment the ref count.
     wgpu::Texture dawnTexture         = texture.getDawnTexturePtr();
     wgpu::TextureView dawnTextureView = texture.getDawnTextureViewPtr();
     SkASSERT(!dawnTexture || !dawnTextureView);

     if (!dawnTexture && !dawnTextureView) {
         return {};
     }

     if (dawnTexture) {
         return DawnTexture::MakeWrapped(this->dawnSharedContext(),
                                         texture.dimensions(),
                                         texture.info(),
                                         std::move(dawnTexture));
     } else {
         return DawnTexture::MakeWrapped(this->dawnSharedContext(),
                                         texture.dimensions(),
                                         texture.info(),
                                         std::move(dawnTextureView));
     }
 }

 sk_sp<DawnTexture> DawnResourceProvider::findOrCreateDiscardableMSAALoadTexture(
         SkISize dimensions, const TextureInfo& msaaInfo) {
     SkASSERT(msaaInfo.isValid());

     // Derive the load texture's info from MSAA texture's info.
     DawnTextureInfo dawnMsaaLoadTextureInfo;
     msaaInfo.getDawnTextureInfo(&dawnMsaaLoadTextureInfo);
     dawnMsaaLoadTextureInfo.fSampleCount = 1;
     dawnMsaaLoadTextureInfo.fUsage |= wgpu::TextureUsage::TextureBinding;

 #if !defined(__EMSCRIPTEN__)
     // MSAA texture can be transient attachment (memoryless) but the load texture cannot be.
     // This is because the load texture will need to have its content retained between two passes
     // loading:
     // - first pass: the resolve texture is blitted to the load texture.
     // - 2nd pass: the actual render pass is started and the load texture is blitted to the MSAA
     // texture.
     dawnMsaaLoadTextureInfo.fUsage &= (~wgpu::TextureUsage::TransientAttachment);
 #endif

     auto texture = this->findOrCreateDiscardableMSAAAttachment(dimensions, dawnMsaaLoadTextureInfo);

     return sk_sp<DawnTexture>(static_cast<DawnTexture*>(texture.release()));
 }

 sk_sp<GraphicsPipeline> DawnResourceProvider::createGraphicsPipeline(
         const RuntimeEffectDictionary* runtimeDict,
         const GraphicsPipelineDesc& pipelineDesc,
         const RenderPassDesc& renderPassDesc) {
     return DawnGraphicsPipeline::Make(this->dawnSharedContext(),
                                       this,
                                       runtimeDict,
                                       pipelineDesc,
                                       renderPassDesc);
 }

 sk_sp<ComputePipeline> DawnResourceProvider::createComputePipeline(
         const ComputePipelineDesc& desc) {
     return DawnComputePipeline::Make(this->dawnSharedContext(), desc);
 }

 sk_sp<Texture> DawnResourceProvider::createTexture(SkISize dimensions,
                                                    const TextureInfo& info,
                                                    skgpu::Budgeted budgeted) {
     return DawnTexture::Make(this->dawnSharedContext(),
                              dimensions,
                              info,
                              budgeted);
 }

 sk_sp<Buffer> DawnResourceProvider::createBuffer(size_t size,
                                                  BufferType type,
                                                  AccessPattern accessPattern) {
     return DawnBuffer::Make(this->dawnSharedContext(), size, type, accessPattern);
 }

 sk_sp<Sampler> DawnResourceProvider::createSampler(const SamplerDesc& samplerDesc) {
     return DawnSampler::Make(this->dawnSharedContext(),
                              samplerDesc.samplingOptions(),
                              samplerDesc.tileModeX(),
                              samplerDesc.tileModeY());
 }

 BackendTexture DawnResourceProvider::onCreateBackendTexture(SkISize dimensions,
                                                             const TextureInfo& info) {
     wgpu::Texture texture = DawnTexture::MakeDawnTexture(this->dawnSharedContext(),
                                                          dimensions,
                                                          info);
     if (!texture) {
         return {};
     }

     return BackendTexture(texture.MoveToCHandle());
 }

 void DawnResourceProvider::onDeleteBackendTexture(const BackendTexture& texture) {
     SkASSERT(texture.isValid());
     SkASSERT(texture.backend() == BackendApi::kDawn);

     // Automatically release the pointers in wgpu::TextureView & wgpu::Texture's dtor.
     // Acquire() won't increment the ref count.
     wgpu::TextureView::Acquire(texture.getDawnTextureViewPtr());
     // We need to explicitly call Destroy() here since since that is the recommended way to delete
     // a Dawn texture predictably versus just dropping a ref and relying on garbage collection.
     //
     // Additionally this helps to work around an issue where Skia may have cached a BindGroup that
     // references the underlying texture. Skia currently doesn't destroy BindGroups when its use of
     // the texture goes away, thus a ref to the texture remains on the BindGroup and memory is never
     // cleared up unless we call Destroy() here.
     wgpu::Texture::Acquire(texture.getDawnTexturePtr()).Destroy();
 }

 DawnSharedContext* DawnResourceProvider::dawnSharedContext() const {
     return static_cast<DawnSharedContext*>(fSharedContext);
 }

 sk_sp<DawnBuffer> DawnResourceProvider::findOrCreateDawnBuffer(size_t size,
                                                                BufferType type,
                                                                AccessPattern accessPattern,
                                                                std::string_view label) {
     sk_sp<Buffer> buffer = this->findOrCreateBuffer(size, type, accessPattern, std::move(label));
     DawnBuffer* ptr = static_cast<DawnBuffer*>(buffer.release());
     return sk_sp<DawnBuffer>(ptr);
 }

 const wgpu::BindGroupLayout& DawnResourceProvider::getOrCreateUniformBuffersBindGroupLayout() {
     if (fUniformBuffersBindGroupLayout) {
         return fUniformBuffersBindGroupLayout;
     }

     std::array<wgpu::BindGroupLayoutEntry, 3> entries;
     entries[0].binding = DawnGraphicsPipeline::kIntrinsicUniformBufferIndex;
     entries[0].visibility = wgpu::ShaderStage::Vertex | wgpu::ShaderStage::Fragment;
     entries[0].buffer.type = wgpu::BufferBindingType::Uniform;
     entries[0].buffer.hasDynamicOffset = true;
     entries[0].buffer.minBindingSize = 0;

     entries[1].binding = DawnGraphicsPipeline::kRenderStepUniformBufferIndex;
     entries[1].visibility = wgpu::ShaderStage::Vertex | wgpu::ShaderStage::Fragment;
     entries[1].buffer.type = fSharedContext->caps()->storageBufferPreferred()
                                      ? wgpu::BufferBindingType::ReadOnlyStorage
                                      : wgpu::BufferBindingType::Uniform;
     entries[1].buffer.hasDynamicOffset = true;
     entries[1].buffer.minBindingSize = 0;

     entries[2].binding = DawnGraphicsPipeline::kPaintUniformBufferIndex;
     entries[2].visibility = wgpu::ShaderStage::Fragment;
     entries[2].buffer.type = fSharedContext->caps()->storageBufferPreferred()
                                      ? wgpu::BufferBindingType::ReadOnlyStorage
                                      : wgpu::BufferBindingType::Uniform;
     entries[2].buffer.hasDynamicOffset = true;
     entries[2].buffer.minBindingSize = 0;

     wgpu::BindGroupLayoutDescriptor groupLayoutDesc;
     if (fSharedContext->caps()->setBackendLabels()) {
         groupLayoutDesc.label = "Uniform buffers bind group layout";
     }

     groupLayoutDesc.entryCount = entries.size();
     groupLayoutDesc.entries = entries.data();
     fUniformBuffersBindGroupLayout =
             this->dawnSharedContext()->device().CreateBindGroupLayout(&groupLayoutDesc);

     return fUniformBuffersBindGroupLayout;
 }

 const wgpu::BindGroupLayout&
 DawnResourceProvider::getOrCreateSingleTextureSamplerBindGroupLayout() {
     if (fSingleTextureSamplerBindGroupLayout) {
         return fSingleTextureSamplerBindGroupLayout;
     }

     std::array<wgpu::BindGroupLayoutEntry, 2> entries;

     entries[0].binding = 0;
     entries[0].visibility = wgpu::ShaderStage::Fragment;
     entries[0].sampler.type = wgpu::SamplerBindingType::Filtering;

     entries[1].binding = 1;
     entries[1].visibility = wgpu::ShaderStage::Fragment;
     entries[1].texture.sampleType = wgpu::TextureSampleType::Float;
     entries[1].texture.viewDimension = wgpu::TextureViewDimension::e2D;
     entries[1].texture.multisampled = false;

     wgpu::BindGroupLayoutDescriptor groupLayoutDesc;
     if (fSharedContext->caps()->setBackendLabels()) {
         groupLayoutDesc.label = "Single texture + sampler bind group layout";
     }

     groupLayoutDesc.entryCount = entries.size();
     groupLayoutDesc.entries = entries.data();
     fSingleTextureSamplerBindGroupLayout =
             this->dawnSharedContext()->device().CreateBindGroupLayout(&groupLayoutDesc);

     return fSingleTextureSamplerBindGroupLayout;
 }

 const wgpu::Buffer& DawnResourceProvider::getOrCreateNullBuffer() {
     if (!fNullBuffer) {
         wgpu::BufferDescriptor desc;
         if (fSharedContext->caps()->setBackendLabels()) {
             desc.label = "UnusedBufferSlot";
         }
         desc.usage = wgpu::BufferUsage::CopyDst | wgpu::BufferUsage::Uniform |
                      wgpu::BufferUsage::Storage;
         desc.size = kBufferBindingSizeAlignment;
         desc.mappedAtCreation = false;

         fNullBuffer = this->dawnSharedContext()->device().CreateBuffer(&desc);
         SkASSERT(fNullBuffer);
     }

     return fNullBuffer;
 }

 const wgpu::BindGroup& DawnResourceProvider::findOrCreateUniformBuffersBindGroup(
         const std::array<std::pair<const DawnBuffer*, uint32_t>, 3>& boundBuffersAndSizes) {
     auto key = make_ubo_bind_group_key(boundBuffersAndSizes);
     auto* existingBindGroup = fUniformBufferBindGroupCache.find(key);
     if (existingBindGroup) {
         // cache hit.
         return *existingBindGroup;
     }

     // Translate to wgpu::BindGroupDescriptor
     std::array<wgpu::BindGroupEntry, 3> entries;

     constexpr uint32_t kBindingIndices[] = {
         DawnGraphicsPipeline::kIntrinsicUniformBufferIndex,
         DawnGraphicsPipeline::kRenderStepUniformBufferIndex,
         DawnGraphicsPipeline::kPaintUniformBufferIndex,
     };

     for (uint32_t i = 0; i < boundBuffersAndSizes.size(); ++i) {
         const DawnBuffer* boundBuffer = boundBuffersAndSizes[i].first;
         const uint32_t bindingSize = boundBuffersAndSizes[i].second;

         entries[i].binding = kBindingIndices[i];
         entries[i].offset = 0;
         if (boundBuffer) {
             entries[i].buffer = boundBuffer->dawnBuffer();
             entries[i].size = SkAlignTo(bindingSize, kBufferBindingSizeAlignment);
         } else {
             entries[i].buffer = this->getOrCreateNullBuffer();
             entries[i].size = wgpu::kWholeSize;
         }
     }

     wgpu::BindGroupDescriptor desc;
     desc.layout = this->getOrCreateUniformBuffersBindGroupLayout();
     desc.entryCount = entries.size();
     desc.entries = entries.data();

     const auto& device = this->dawnSharedContext()->device();
     auto bindGroup = device.CreateBindGroup(&desc);

     return *fUniformBufferBindGroupCache.insert(key, bindGroup);
 }

 const wgpu::BindGroup& DawnResourceProvider::findOrCreateSingleTextureSamplerBindGroup(
         const DawnSampler* sampler, const DawnTexture* texture) {
     auto key = make_texture_bind_group_key(sampler, texture);
     auto* existingBindGroup = fSingleTextureSamplerBindGroups.find(key);
     if (existingBindGroup) {
         // cache hit.
         return *existingBindGroup;
     }

     std::array<wgpu::BindGroupEntry, 2> entries;

     entries[0].binding = 0;
     entries[0].sampler = sampler->dawnSampler();
     entries[1].binding = 1;
     entries[1].textureView = texture->sampleTextureView();

     wgpu::BindGroupDescriptor desc;
     desc.layout = getOrCreateSingleTextureSamplerBindGroupLayout();
     desc.entryCount = entries.size();
     desc.entries = entries.data();

     const auto& device = this->dawnSharedContext()->device();
     auto bindGroup = device.CreateBindGroup(&desc);

     return *fSingleTextureSamplerBindGroups.insert(key, bindGroup);
 }

 } // namespace skgpu::graphite
	/*
	* Copyright 2022 Google LLC
	*
	* Use of this source code is governed by a BSD-style license that can be
	* found in the LICENSE file.
	*/

	#include "src/gpu/graphite/dawn/DawnResourceProvider.h"

	#include "include/gpu/graphite/BackendTexture.h"
	#include "include/gpu/graphite/TextureInfo.h"
	#include "include/private/base/SkAlign.h"
	#include "src/gpu/graphite/ComputePipeline.h"
	#include "src/gpu/graphite/RenderPassDesc.h"
	#include "src/gpu/graphite/dawn/DawnBuffer.h"
	#include "src/gpu/graphite/dawn/DawnComputePipeline.h"
	#include "src/gpu/graphite/dawn/DawnErrorChecker.h"
	#include "src/gpu/graphite/dawn/DawnGraphicsPipeline.h"
	#include "src/gpu/graphite/dawn/DawnSampler.h"
	#include "src/gpu/graphite/dawn/DawnSharedContext.h"
	#include "src/gpu/graphite/dawn/DawnTexture.h"
	#include "src/sksl/SkSLCompiler.h"

	namespace skgpu::graphite {

	namespace {

	constexpr int kBufferBindingSizeAlignment = 16;
	constexpr int kMaxNumberOfCachedBufferBindGroups = 32;
	constexpr int kMaxNumberOfCachedTextureBindGroups = 4096;

	wgpu::ShaderModule create_shader_module(const wgpu::Device& device, const char* source) {
	wgpu::ShaderModuleWGSLDescriptor wgslDesc;
	wgslDesc.code = source;
	wgpu::ShaderModuleDescriptor descriptor;
	descriptor.nextInChain = &wgslDesc;
	return device.CreateShaderModule(&descriptor);
	}

	wgpu::RenderPipeline create_blit_render_pipeline(const DawnSharedContext* sharedContext,
	const char* label,
	wgpu::ShaderModule vsModule,
	wgpu::ShaderModule fsModule,
	wgpu::TextureFormat renderPassColorFormat,
	wgpu::TextureFormat renderPassDepthStencilFormat,
	int numSamples) {
	wgpu::RenderPipelineDescriptor descriptor;
	descriptor.label = label;
	descriptor.layout = nullptr;

	wgpu::ColorTargetState colorTarget;
	colorTarget.format = renderPassColorFormat;
	colorTarget.blend = nullptr;
	colorTarget.writeMask = wgpu::ColorWriteMask::All;

	wgpu::DepthStencilState depthStencil;
	if (renderPassDepthStencilFormat != wgpu::TextureFormat::Undefined) {
	depthStencil.format = renderPassDepthStencilFormat;
	depthStencil.depthWriteEnabled = false;
	depthStencil.depthCompare = wgpu::CompareFunction::Always;

	descriptor.depthStencil = &depthStencil;
	}

	wgpu::FragmentState fragment;
	fragment.module = std::move(fsModule);
	fragment.entryPoint = "main";
	fragment.targetCount = 1;
	fragment.targets = &colorTarget;
	descriptor.fragment = &fragment;

	descriptor.vertex.module = std::move(vsModule);
	descriptor.vertex.entryPoint = "main";
	descriptor.vertex.constantCount = 0;
	descriptor.vertex.constants = nullptr;
	descriptor.vertex.bufferCount = 0;
	descriptor.vertex.buffers = nullptr;

	descriptor.primitive.frontFace = wgpu::FrontFace::CCW;
	descriptor.primitive.cullMode = wgpu::CullMode::None;
	descriptor.primitive.topology = wgpu::PrimitiveTopology::TriangleStrip;
	descriptor.primitive.stripIndexFormat = wgpu::IndexFormat::Undefined;

	descriptor.multisample.count = numSamples;
	descriptor.multisample.mask = 0xFFFFFFFF;
	descriptor.multisample.alphaToCoverageEnabled = false;

	std::optional<DawnErrorChecker> errorChecker;
	if (sharedContext->dawnCaps()->allowScopedErrorChecks()) {
	errorChecker.emplace(sharedContext);
	}
	auto pipeline = sharedContext->device().CreateRenderPipeline(&descriptor);
	if (errorChecker.has_value() && errorChecker->popErrorScopes() != DawnErrorType::kNoError) {
	return nullptr;
	}

	return pipeline;
	}

	UniqueKey make_ubo_bind_group_key(
	const std::array<std::pair<const DawnBuffer*, uint32_t>, 3>& boundBuffersAndSizes) {
	static const UniqueKey::Domain kBufferBindGroupDomain = UniqueKey::GenerateDomain();

	UniqueKey uniqueKey;
	{
	// Each entry in the bind group needs 2 uint32_t in the key:
	// - buffer's unique ID: 32 bits.
	// - buffer's binding size: 32 bits.
	// We need total of 3 entries in the uniform buffer bind group.
	// Unused entries will be assigned zero values.
	UniqueKey::Builder builder(
	&uniqueKey, kBufferBindGroupDomain, 6, "GraphicsPipelineBufferBindGroup");

	for (uint32_t i = 0; i < boundBuffersAndSizes.size(); ++i) {
	const DawnBuffer* boundBuffer = boundBuffersAndSizes[i].first;
	const uint32_t bindingSize = boundBuffersAndSizes[i].second;
	if (boundBuffer) {
	builder[2 * i] = boundBuffer->uniqueID().asUInt();
	builder[2 * i + 1] = bindingSize;
	} else {
	builder[2 * i] = 0;
	builder[2 * i + 1] = 0;
	}
	}

	builder.finish();
	}

	return uniqueKey;
	}

	UniqueKey make_texture_bind_group_key(const DawnSampler* sampler, const DawnTexture* texture) {
	static const UniqueKey::Domain kTextureBindGroupDomain = UniqueKey::GenerateDomain();

	UniqueKey uniqueKey;
	{
	UniqueKey::Builder builder(&uniqueKey,
	kTextureBindGroupDomain,
	2,
	"GraphicsPipelineSingleTextureSamplerBindGroup");

	builder[0] = sampler->uniqueID().asUInt();
	builder[1] = texture->uniqueID().asUInt();

	builder.finish();
	}

	return uniqueKey;
	}
	} // namespace

	DawnResourceProvider::DawnResourceProvider(SharedContext* sharedContext,
	SingleOwner* singleOwner,
	uint32_t recorderID,
	size_t resourceBudget)
	: ResourceProvider(sharedContext, singleOwner, recorderID, resourceBudget)
	, fUniformBufferBindGroupCache(kMaxNumberOfCachedBufferBindGroups)
	, fSingleTextureSamplerBindGroups(kMaxNumberOfCachedTextureBindGroups) {}

	DawnResourceProvider::~DawnResourceProvider() = default;

	wgpu::RenderPipeline DawnResourceProvider::findOrCreateBlitWithDrawPipeline(
	const RenderPassDesc& renderPassDesc) {
	uint64_t renderPassKey =
	this->dawnSharedContext()->dawnCaps()->getRenderPassDescKey(renderPassDesc);
	wgpu::RenderPipeline pipeline = fBlitWithDrawPipelines[renderPassKey];
	if (!pipeline) {
	static constexpr char kVertexShaderText[] = R"(
	var<private> fullscreenTriPositions : array<vec2<f32>, 3> = array<vec2<f32>, 3>(
	vec2(-1.0, -1.0), vec2(-1.0, 3.0), vec2(3.0, -1.0));

	@vertex
	fn main(@builtin(vertex_index) vertexIndex : u32) -> @builtin(position) vec4<f32> {
	return vec4(fullscreenTriPositions[vertexIndex], 1.0, 1.0);
	}
	)";

	static constexpr char kFragmentShaderText[] = R"(
	@group(0) @binding(0) var colorMap: texture_2d<f32>;

	@fragment
	fn main(@builtin(position) fragPosition : vec4<f32>) -> @location(0) vec4<f32> {
	var coords : vec2<i32> = vec2<i32>(i32(fragPosition.x), i32(fragPosition.y));
	return textureLoad(colorMap, coords, 0);
	}
	)";

	auto vsModule = create_shader_module(dawnSharedContext()->device(), kVertexShaderText);
	auto fsModule = create_shader_module(dawnSharedContext()->device(), kFragmentShaderText);

	pipeline = create_blit_render_pipeline(
	dawnSharedContext(),
	/label=/"BlitWithDraw",
	std::move(vsModule),
	std::move(fsModule),
	/renderPassColorFormat=/
	renderPassDesc.fColorAttachment.fTextureInfo.dawnTextureSpec().getViewFormat(),
	/renderPassDepthStencilFormat=/
	renderPassDesc.fDepthStencilAttachment.fTextureInfo.isValid()
	? renderPassDesc.fDepthStencilAttachment.fTextureInfo.dawnTextureSpec()
	.getViewFormat()
	: wgpu::TextureFormat::Undefined,
	/numSamples=/renderPassDesc.fColorAttachment.fTextureInfo.numSamples());

	if (pipeline) {
	fBlitWithDrawPipelines.set(renderPassKey, pipeline);
	}
	}

	return pipeline;
	}

	sk_sp<Texture> DawnResourceProvider::onCreateWrappedTexture(const BackendTexture& texture) {
	// Convert to smart pointers. wgpu::Texture* constructor will increment the ref count.
	wgpu::Texture dawnTexture = texture.getDawnTexturePtr();
	wgpu::TextureView dawnTextureView = texture.getDawnTextureViewPtr();
	SkASSERT(!dawnTexture \|\| !dawnTextureView);

	if (!dawnTexture && !dawnTextureView) {
	return {};
	}

	if (dawnTexture) {
	return DawnTexture::MakeWrapped(this->dawnSharedContext(),
	texture.dimensions(),
	texture.info(),
	std::move(dawnTexture));
	} else {
	return DawnTexture::MakeWrapped(this->dawnSharedContext(),
	texture.dimensions(),
	texture.info(),
	std::move(dawnTextureView));
	}
	}

	sk_sp<DawnTexture> DawnResourceProvider::findOrCreateDiscardableMSAALoadTexture(
	SkISize dimensions, const TextureInfo& msaaInfo) {
	SkASSERT(msaaInfo.isValid());

	// Derive the load texture's info from MSAA texture's info.
	DawnTextureInfo dawnMsaaLoadTextureInfo;
	msaaInfo.getDawnTextureInfo(&dawnMsaaLoadTextureInfo);
	dawnMsaaLoadTextureInfo.fSampleCount = 1;
	dawnMsaaLoadTextureInfo.fUsage \|= wgpu::TextureUsage::TextureBinding;

	#if !defined(__EMSCRIPTEN__)
	// MSAA texture can be transient attachment (memoryless) but the load texture cannot be.
	// This is because the load texture will need to have its content retained between two passes
	// loading:
	// - first pass: the resolve texture is blitted to the load texture.
	// - 2nd pass: the actual render pass is started and the load texture is blitted to the MSAA
	// texture.
	dawnMsaaLoadTextureInfo.fUsage &= (~wgpu::TextureUsage::TransientAttachment);
	#endif

	auto texture = this->findOrCreateDiscardableMSAAAttachment(dimensions, dawnMsaaLoadTextureInfo);

	return sk_sp<DawnTexture>(static_cast<DawnTexture*>(texture.release()));
	}

	sk_sp<GraphicsPipeline> DawnResourceProvider::createGraphicsPipeline(
	const RuntimeEffectDictionary* runtimeDict,
	const GraphicsPipelineDesc& pipelineDesc,
	const RenderPassDesc& renderPassDesc) {
	return DawnGraphicsPipeline::Make(this->dawnSharedContext(),
	this,
	runtimeDict,
	pipelineDesc,
	renderPassDesc);
	}

	sk_sp<ComputePipeline> DawnResourceProvider::createComputePipeline(
	const ComputePipelineDesc& desc) {
	return DawnComputePipeline::Make(this->dawnSharedContext(), desc);
	}

	sk_sp<Texture> DawnResourceProvider::createTexture(SkISize dimensions,
	const TextureInfo& info,
	skgpu::Budgeted budgeted) {
	return DawnTexture::Make(this->dawnSharedContext(),
	dimensions,
	info,
	budgeted);
	}

	sk_sp<Buffer> DawnResourceProvider::createBuffer(size_t size,
	BufferType type,
	AccessPattern accessPattern) {
	return DawnBuffer::Make(this->dawnSharedContext(), size, type, accessPattern);
	}

	sk_sp<Sampler> DawnResourceProvider::createSampler(const SamplerDesc& samplerDesc) {
	return DawnSampler::Make(this->dawnSharedContext(),
	samplerDesc.samplingOptions(),
	samplerDesc.tileModeX(),
	samplerDesc.tileModeY());
	}

	BackendTexture DawnResourceProvider::onCreateBackendTexture(SkISize dimensions,
	const TextureInfo& info) {
	wgpu::Texture texture = DawnTexture::MakeDawnTexture(this->dawnSharedContext(),
	dimensions,
	info);
	if (!texture) {
	return {};
	}

	return BackendTexture(texture.MoveToCHandle());
	}

	void DawnResourceProvider::onDeleteBackendTexture(const BackendTexture& texture) {
	SkASSERT(texture.isValid());
	SkASSERT(texture.backend() == BackendApi::kDawn);

	// Automatically release the pointers in wgpu::TextureView & wgpu::Texture's dtor.
	// Acquire() won't increment the ref count.
	wgpu::TextureView::Acquire(texture.getDawnTextureViewPtr());
	// We need to explicitly call Destroy() here since since that is the recommended way to delete
	// a Dawn texture predictably versus just dropping a ref and relying on garbage collection.
	//
	// Additionally this helps to work around an issue where Skia may have cached a BindGroup that
	// references the underlying texture. Skia currently doesn't destroy BindGroups when its use of
	// the texture goes away, thus a ref to the texture remains on the BindGroup and memory is never
	// cleared up unless we call Destroy() here.
	wgpu::Texture::Acquire(texture.getDawnTexturePtr()).Destroy();
	}

	DawnSharedContext* DawnResourceProvider::dawnSharedContext() const {
	return static_cast<DawnSharedContext*>(fSharedContext);
	}

	sk_sp<DawnBuffer> DawnResourceProvider::findOrCreateDawnBuffer(size_t size,
	BufferType type,
	AccessPattern accessPattern,
	std::string_view label) {
	sk_sp<Buffer> buffer = this->findOrCreateBuffer(size, type, accessPattern, std::move(label));
	DawnBuffer* ptr = static_cast<DawnBuffer*>(buffer.release());
	return sk_sp<DawnBuffer>(ptr);
	}

	const wgpu::BindGroupLayout& DawnResourceProvider::getOrCreateUniformBuffersBindGroupLayout() {
	if (fUniformBuffersBindGroupLayout) {
	return fUniformBuffersBindGroupLayout;
	}

	std::array<wgpu::BindGroupLayoutEntry, 3> entries;
	entries[0].binding = DawnGraphicsPipeline::kIntrinsicUniformBufferIndex;
	entries[0].visibility = wgpu::ShaderStage::Vertex \| wgpu::ShaderStage::Fragment;
	entries[0].buffer.type = wgpu::BufferBindingType::Uniform;
	entries[0].buffer.hasDynamicOffset = true;
	entries[0].buffer.minBindingSize = 0;

	entries[1].binding = DawnGraphicsPipeline::kRenderStepUniformBufferIndex;
	entries[1].visibility = wgpu::ShaderStage::Vertex \| wgpu::ShaderStage::Fragment;
	entries[1].buffer.type = fSharedContext->caps()->storageBufferPreferred()
	? wgpu::BufferBindingType::ReadOnlyStorage
	: wgpu::BufferBindingType::Uniform;
	entries[1].buffer.hasDynamicOffset = true;
	entries[1].buffer.minBindingSize = 0;

	entries[2].binding = DawnGraphicsPipeline::kPaintUniformBufferIndex;
	entries[2].visibility = wgpu::ShaderStage::Fragment;
	entries[2].buffer.type = fSharedContext->caps()->storageBufferPreferred()
	? wgpu::BufferBindingType::ReadOnlyStorage
	: wgpu::BufferBindingType::Uniform;
	entries[2].buffer.hasDynamicOffset = true;
	entries[2].buffer.minBindingSize = 0;

	wgpu::BindGroupLayoutDescriptor groupLayoutDesc;
	if (fSharedContext->caps()->setBackendLabels()) {
	groupLayoutDesc.label = "Uniform buffers bind group layout";
	}

	groupLayoutDesc.entryCount = entries.size();
	groupLayoutDesc.entries = entries.data();
	fUniformBuffersBindGroupLayout =
	this->dawnSharedContext()->device().CreateBindGroupLayout(&groupLayoutDesc);

	return fUniformBuffersBindGroupLayout;
	}

	const wgpu::BindGroupLayout&
	DawnResourceProvider::getOrCreateSingleTextureSamplerBindGroupLayout() {
	if (fSingleTextureSamplerBindGroupLayout) {
	return fSingleTextureSamplerBindGroupLayout;
	}

	std::array<wgpu::BindGroupLayoutEntry, 2> entries;

	entries[0].binding = 0;
	entries[0].visibility = wgpu::ShaderStage::Fragment;
	entries[0].sampler.type = wgpu::SamplerBindingType::Filtering;

	entries[1].binding = 1;
	entries[1].visibility = wgpu::ShaderStage::Fragment;
	entries[1].texture.sampleType = wgpu::TextureSampleType::Float;
	entries[1].texture.viewDimension = wgpu::TextureViewDimension::e2D;
	entries[1].texture.multisampled = false;

	wgpu::BindGroupLayoutDescriptor groupLayoutDesc;
	if (fSharedContext->caps()->setBackendLabels()) {
	groupLayoutDesc.label = "Single texture + sampler bind group layout";
	}

	groupLayoutDesc.entryCount = entries.size();
	groupLayoutDesc.entries = entries.data();
	fSingleTextureSamplerBindGroupLayout =
	this->dawnSharedContext()->device().CreateBindGroupLayout(&groupLayoutDesc);

	return fSingleTextureSamplerBindGroupLayout;
	}

	const wgpu::Buffer& DawnResourceProvider::getOrCreateNullBuffer() {
	if (!fNullBuffer) {
	wgpu::BufferDescriptor desc;
	if (fSharedContext->caps()->setBackendLabels()) {
	desc.label = "UnusedBufferSlot";
	}
	desc.usage = wgpu::BufferUsage::CopyDst \| wgpu::BufferUsage::Uniform \|
	wgpu::BufferUsage::Storage;
	desc.size = kBufferBindingSizeAlignment;
	desc.mappedAtCreation = false;

	fNullBuffer = this->dawnSharedContext()->device().CreateBuffer(&desc);
	SkASSERT(fNullBuffer);
	}

	return fNullBuffer;
	}

	const wgpu::BindGroup& DawnResourceProvider::findOrCreateUniformBuffersBindGroup(
	const std::array<std::pair<const DawnBuffer*, uint32_t>, 3>& boundBuffersAndSizes) {
	auto key = make_ubo_bind_group_key(boundBuffersAndSizes);
	auto* existingBindGroup = fUniformBufferBindGroupCache.find(key);
	if (existingBindGroup) {
	// cache hit.
	return *existingBindGroup;
	}

	// Translate to wgpu::BindGroupDescriptor
	std::array<wgpu::BindGroupEntry, 3> entries;

	constexpr uint32_t kBindingIndices[] = {
	DawnGraphicsPipeline::kIntrinsicUniformBufferIndex,
	DawnGraphicsPipeline::kRenderStepUniformBufferIndex,
	DawnGraphicsPipeline::kPaintUniformBufferIndex,
	};

	for (uint32_t i = 0; i < boundBuffersAndSizes.size(); ++i) {
	const DawnBuffer* boundBuffer = boundBuffersAndSizes[i].first;
	const uint32_t bindingSize = boundBuffersAndSizes[i].second;

	entries[i].binding = kBindingIndices[i];
	entries[i].offset = 0;
	if (boundBuffer) {
	entries[i].buffer = boundBuffer->dawnBuffer();
	entries[i].size = SkAlignTo(bindingSize, kBufferBindingSizeAlignment);
	} else {
	entries[i].buffer = this->getOrCreateNullBuffer();
	entries[i].size = wgpu::kWholeSize;
	}
	}

	wgpu::BindGroupDescriptor desc;
	desc.layout = this->getOrCreateUniformBuffersBindGroupLayout();
	desc.entryCount = entries.size();
	desc.entries = entries.data();

	const auto& device = this->dawnSharedContext()->device();
	auto bindGroup = device.CreateBindGroup(&desc);

	return *fUniformBufferBindGroupCache.insert(key, bindGroup);
	}

	const wgpu::BindGroup& DawnResourceProvider::findOrCreateSingleTextureSamplerBindGroup(
	const DawnSampler* sampler, const DawnTexture* texture) {
	auto key = make_texture_bind_group_key(sampler, texture);
	auto* existingBindGroup = fSingleTextureSamplerBindGroups.find(key);
	if (existingBindGroup) {
	// cache hit.
	return *existingBindGroup;
	}

	std::array<wgpu::BindGroupEntry, 2> entries;

	entries[0].binding = 0;
	entries[0].sampler = sampler->dawnSampler();
	entries[1].binding = 1;
	entries[1].textureView = texture->sampleTextureView();

	wgpu::BindGroupDescriptor desc;
	desc.layout = getOrCreateSingleTextureSamplerBindGroupLayout();
	desc.entryCount = entries.size();
	desc.entries = entries.data();

	const auto& device = this->dawnSharedContext()->device();
	auto bindGroup = device.CreateBindGroup(&desc);

	return *fSingleTextureSamplerBindGroups.insert(key, bindGroup);
	}

	} // namespace skgpu::graphite