[hgiWebGPU]: Modify staging buffer implementation (PixarAnimationStud…

…ios#1124) * [hgiWebGPU]: Modify staging buffer implementation - Postpone staging buffer creation until required - Use ABSL_ENABLE_INSTALL options for dawn cmake build to avoid manual copy
autodesk-forks · Jul 18, 2024 · a31e0d3 · a31e0d3
1 parent 3566f69
commit a31e0d3
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Showing 3 changed files with 18 additions and 26 deletions.
diff --git a/build_scripts/build_usd.py b/build_scripts/build_usd.py
@@ -1769,6 +1769,7 @@ def InstallDawn(context, force, buildArgs):
                 '-DDAWN_BUILD_SAMPLES=OFF',
                 '-DDAWN_ENABLE_INSTALL=ON',
                 '-DDAWN_USE_GLFW=OFF',
+                '-DABSL_ENABLE_INSTALL=ON'
             ]
             if Windows():
                 cmakeOptions.append('-DBUILD_SHARED_LIBS=OFF')
@@ -1797,17 +1798,6 @@ def InstallDawn(context, force, buildArgs):
         CopyFiles(context, "src/dawn/common/{buildConfig}*.*".format(buildConfig=buildConfigFolder), "lib")
         CopyFiles(context, "third_party/spirv-tools/source/{buildConfig}*SPIRV-Tools.*".format(buildConfig=buildConfigFolder), "lib")
         CopyFiles(context, "third_party/spirv-tools/source/opt/{buildConfig}*SPIRV-Tools-opt.*".format(buildConfig=buildConfigFolder), "lib")
-        CopyFiles(context, "third_party/abseil/absl/base/{buildConfig}*.*".format(buildConfig=buildConfigFolder), "lib")
-        CopyFiles(context, "third_party/abseil/absl/container/{buildConfig}*.*".format(buildConfig=buildConfigFolder), "lib")
-        CopyFiles(context, "third_party/abseil/absl/crc/{buildConfig}*.*".format(buildConfig=buildConfigFolder), "lib")
-        CopyFiles(context, "third_party/abseil/absl/debugging/{buildConfig}*.*".format(buildConfig=buildConfigFolder), "lib")
-        CopyFiles(context, "third_party/abseil/absl/hash/{buildConfig}*.*".format(buildConfig=buildConfigFolder), "lib")
-        CopyFiles(context, "third_party/abseil/absl/numeric/{buildConfig}*.*".format(buildConfig=buildConfigFolder), "lib")
-        CopyFiles(context, "third_party/abseil/absl/profiling/{buildConfig}*.*".format(buildConfig=buildConfigFolder), "lib")
-        CopyFiles(context, "third_party/abseil/absl/strings/{buildConfig}*.*".format(buildConfig=buildConfigFolder), "lib")
-        CopyFiles(context, "third_party/abseil/absl/synchronization/{buildConfig}*.*".format(buildConfig=buildConfigFolder), "lib")
-        CopyFiles(context, "third_party/abseil/absl/time/{buildConfig}*.*".format(buildConfig=buildConfigFolder), "lib")
-        CopyFiles(context, "third_party/abseil/absl/types/{buildConfig}*.*".format(buildConfig=buildConfigFolder), "lib")
         CopyFiles(context, "src/tint/{buildConfig}*.*".format(buildConfig=buildConfigFolder), "lib")
         # Extra include files
         CopyFiles(context, "gen/include/dawn/*.*", "include/dawn")

diff --git a/pxr/imaging/hgiWebGPU/buffer.cpp b/pxr/imaging/hgiWebGPU/buffer.cpp
@@ -44,27 +44,17 @@ HgiWebGPUBuffer::HgiWebGPUBuffer(HgiWebGPU *hgi, HgiBufferDesc const & desc)
     bufferDesc.label = desc.debugName.c_str();
     bufferDesc.usage = HgiWebGPUConversions::GetBufferUsage(desc.usage);
 
-    if( desc.usage & HgiBufferUsageIndex32 || desc.usage & HgiBufferUsageVertex || desc.usage & HgiBufferUsageUniform || desc.usage & HgiBufferUsageStorage)
-        bufferDesc.usage |= wgpu::BufferUsage::CopyDst;
-    else
-        bufferDesc.usage |= wgpu::BufferUsage::MapRead;
-
-    // TODO: We basically need to add all usages since we don't know at this point in time in which stage this will be used.
-    // For example, the pxr/imaging/hdSt/vboMemoryManager.cpp#351 sets HgiBufferUsageUniform | HgiBufferUsageVertex
-    // for the points buffer, which is then later used in the pxr/imaging/hdSt/smoothNormals.cpp#75 with a resource
-    // binding of the type storage, resulting in incompatible types
-    bufferDesc.usage |= wgpu::BufferUsage::CopySrc | wgpu::BufferUsage::CopyDst | wgpu::BufferUsage::Storage | wgpu::BufferUsage::Index;
+    // There is no information on how the buffer will be used after creation so, we add the possibility to use it
+    // as a src or destination for copy operations.
+    bufferDesc.usage |= wgpu::BufferUsage::CopySrc | wgpu::BufferUsage::CopyDst;
 
     bufferDesc.size = desc.byteSize;
     wgpu::Device device = hgi->GetPrimaryDevice();
     _bufferHandle = device.CreateBuffer(&bufferDesc);
 
-    _cpuStagingBuffer.resize(desc.byteSize);
-
     if (desc.initialData) {
         wgpu::Queue queue = hgi->GetQueue();
         queue.WriteBuffer(_bufferHandle, 0, desc.initialData, desc.byteSize);
-        memcpy(_cpuStagingBuffer.data(), desc.initialData, desc.byteSize);
     }
 
     _descriptor.initialData = nullptr;
@@ -73,6 +63,11 @@ HgiWebGPUBuffer::HgiWebGPUBuffer(HgiWebGPU *hgi, HgiBufferDesc const & desc)
 HgiWebGPUBuffer::~HgiWebGPUBuffer()
 {
     _bufferHandle = nullptr;
+
+    if (_cpuStaging) {
+        free(_cpuStaging);
+        _cpuStaging = nullptr;
+    }
 }
 
 size_t
@@ -90,7 +85,14 @@ HgiWebGPUBuffer::GetRawResource() const
 void*
 HgiWebGPUBuffer::GetCPUStagingAddress()
 {
-    return static_cast<void *>(_cpuStagingBuffer.data());
+    if (!_cpuStaging) {
+        _cpuStaging = malloc(_descriptor.byteSize);
+    }
+
+    // This lets the client code memcpy into the cpu staging buffer directly.
+    // The staging data must be explicitly copied to the GPU buffer
+    // via CopyBufferCpuToGpu cmd by the client.
+    return _cpuStaging;
 }
 
 PXR_NAMESPACE_CLOSE_SCOPE
diff --git a/pxr/imaging/hgiWebGPU/buffer.h b/pxr/imaging/hgiWebGPU/buffer.h
@@ -67,7 +67,7 @@ class HgiWebGPUBuffer final : public HgiBuffer {
     HgiWebGPUBuffer(const HgiWebGPUBuffer&) = delete;
 
     wgpu::Buffer _bufferHandle;
-    std::vector<uint8_t> _cpuStagingBuffer;
+    void* _cpuStaging;
 };