| /* |
| * Copyright 2019 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #ifndef GrGpuBuffer_DEFINED |
| #define GrGpuBuffer_DEFINED |
| |
| #include "src/gpu/ganesh/GrBuffer.h" |
| #include "src/gpu/ganesh/GrGpuResource.h" |
| |
| class GrGpu; |
| |
| class GrGpuBuffer : public GrGpuResource, public GrBuffer { |
| public: |
| /** |
| * Computes a scratch key for a GPU-side buffer with a "dynamic" access pattern. (Buffers with |
| * "static" and "stream" patterns are disqualified by nature from being cached and reused.) |
| */ |
| static void ComputeScratchKeyForDynamicBuffer(size_t size, GrGpuBufferType, skgpu::ScratchKey*); |
| |
| GrAccessPattern accessPattern() const { return fAccessPattern; } |
| |
| size_t size() const final { return fSizeInBytes; } |
| |
| void ref() const final { GrGpuResource::ref(); } |
| |
| void unref() const final { GrGpuResource::unref(); } |
| |
| /** |
| * Maps the buffer to be read or written by the CPU. |
| * |
| * It is an error to draw from the buffer while it is mapped or transfer to/from the buffer. It |
| * may fail if the backend doesn't support mapping the buffer. Once a buffer is mapped, |
| * subsequent calls to map() trivially succeed. No matter how many times map() is called, |
| * umap() will unmap the buffer on the first call if it is mapped. |
| * |
| * If the buffer is of type GrGpuBufferType::kXferGpuToCpu then it is mapped for reading only. |
| * Otherwise it is mapped writing only. Writing to a buffer that is mapped for reading or vice |
| * versa produces undefined results. If the buffer is mapped for writing then the buffer's |
| * previous contents are invalidated. |
| * |
| * @return a pointer to the data or nullptr if the map fails. |
| */ |
| void* map(); |
| |
| /** |
| * Unmaps the buffer if it is mapped. |
| * |
| * The pointer returned by the previous map call will no longer be valid. |
| */ |
| void unmap(); |
| |
| /** |
| * Queries whether the buffer has been mapped. |
| * |
| * @return true if the buffer is mapped, false otherwise. |
| */ |
| bool isMapped() const; |
| |
| bool isCpuBuffer() const final { return false; } |
| |
| /** |
| * Overwrites the buffer with zero bytes. Always fails for GrGpuBufferType::kXferGpuToCpu |
| * buffers. The buffer must not currently be mapped. |
| */ |
| bool clearToZero(); |
| |
| /** |
| * Updates the buffer data. |
| * |
| * The size of the buffer will be preserved. The src data will be |
| * placed at offset. If preserve is false then any remaining content |
| * before/after the range [offset, offset+size) becomes undefined. |
| * Preserving updates will fail if the size and offset are not aligned |
| * to GrCaps::bufferUpdateDataPreserveAlignment(). |
| * |
| * The buffer must not be mapped. |
| * |
| * Fails for GrGpuBufferType::kXferGpuToCpu. |
| * |
| * Note that buffer updates do not go through GrContext and therefore are |
| * not serialized with other operations. |
| * |
| * @return returns true if the update succeeds, false otherwise. |
| */ |
| bool updateData(const void* src, size_t offset, size_t size, bool preserve); |
| |
| GrGpuBufferType intendedType() const { return fIntendedType; } |
| |
| protected: |
| GrGpuBuffer(GrGpu*, |
| size_t sizeInBytes, |
| GrGpuBufferType, |
| GrAccessPattern, |
| std::string_view label); |
| |
| enum class MapType { |
| /** Maps for reading. The effect of writes is undefined. */ |
| kRead, |
| /** |
| * Maps for writing. The existing contents are discarded and the initial contents of the |
| * buffer. Reads (even after overwriting initial contents) should be avoided for performance |
| * reasons as the memory may not be cached. |
| */ |
| kWriteDiscard, |
| }; |
| |
| void* fMapPtr; |
| |
| private: |
| /** Currently MapType is determined entirely by the buffer type, as documented in map(). */ |
| MapType mapType() const { |
| return this->intendedType() == GrGpuBufferType::kXferGpuToCpu ? MapType::kRead |
| : MapType::kWriteDiscard; |
| } |
| |
| virtual void onMap(MapType) = 0; |
| virtual void onUnmap(MapType) = 0; |
| virtual bool onClearToZero() = 0; |
| virtual bool onUpdateData(const void* src, size_t offset, size_t size, bool preserve) = 0; |
| |
| size_t onGpuMemorySize() const override { return fSizeInBytes; } |
| void onSetLabel() override{} |
| const char* getResourceType() const override { return "Buffer Object"; } |
| void computeScratchKey(skgpu::ScratchKey* key) const override; |
| |
| size_t fSizeInBytes; |
| GrAccessPattern fAccessPattern; |
| GrGpuBufferType fIntendedType; |
| }; |
| |
| #endif |