| /* |
| * Copyright 2010 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #ifndef skgpu_BufferWriter_DEFINED |
| #define skgpu_BufferWriter_DEFINED |
| |
| #include <type_traits> |
| #include "include/core/SkRect.h" |
| #include "include/private/SkColorData.h" |
| #include "include/private/base/SkTemplates.h" |
| #include "include/private/base/SkVx.h" |
| #include "src/core/SkConvertPixels.h" |
| |
| namespace skgpu { |
| |
| struct BufferWriter { |
| public: |
| // Marks a read-only position in the underlying buffer |
| struct Mark { |
| public: |
| Mark() : Mark(nullptr) {} |
| Mark(void* ptr, size_t offset = 0) |
| : fMark(reinterpret_cast<uintptr_t>(ptr) + offset) { |
| SkASSERT(ptr || offset == 0); |
| } |
| |
| bool operator< (const Mark& o) const { return fMark < o.fMark; } |
| bool operator<=(const Mark& o) const { return fMark <= o.fMark; } |
| bool operator==(const Mark& o) const { return fMark == o.fMark; } |
| bool operator!=(const Mark& o) const { return fMark != o.fMark; } |
| bool operator>=(const Mark& o) const { return fMark >= o.fMark; } |
| bool operator> (const Mark& o) const { return fMark > o.fMark; } |
| |
| ptrdiff_t operator-(const Mark& o) const { return fMark - o.fMark; } |
| |
| explicit operator bool() const { return *this != Mark(); } |
| private: |
| uintptr_t fMark; |
| }; |
| |
| explicit operator bool() const { return fPtr != nullptr; } |
| |
| Mark mark(size_t offset=0) const { |
| this->validate(offset); |
| return Mark(fPtr, offset); |
| } |
| |
| protected: |
| BufferWriter() = default; |
| BufferWriter(void* ptr, size_t size) : fPtr(ptr) { |
| SkDEBUGCODE(fEnd = Mark(ptr, ptr ? size : 0);) |
| } |
| BufferWriter(void* ptr, Mark end = {}) : fPtr(ptr) { |
| SkDEBUGCODE(fEnd = end;) |
| } |
| |
| BufferWriter& operator=(const BufferWriter&) = delete; |
| BufferWriter& operator=(BufferWriter&& that) { |
| fPtr = that.fPtr; |
| that.fPtr = nullptr; |
| SkDEBUGCODE(fEnd = that.fEnd;) |
| SkDEBUGCODE(that.fEnd = Mark();) |
| return *this; |
| } |
| |
| // makeOffset effectively splits the current writer from {fPtr, fEnd} into {fPtr, p} and |
| // a new writer {p, fEnd}. The same data range is accessible, but each byte can only be |
| // set by a single writer. Automatically validates that there is enough bytes remaining in this |
| // writer to do such a split. |
| // |
| // This splitting and validation means that providers of BufferWriters to callers can easily |
| // and correctly track everything in a single BufferWriter field and use |
| // return std::exchange(fCurrWriter, fCurrWriter.makeOffset(requestedBytes)); |
| // This exposes the current writer position to the caller and sets the provider's new current |
| // position to be just after the requested bytes. |
| // |
| // Templated so that it can create subclasses directly. |
| template<typename W> |
| W makeOffset(size_t offsetInBytes) const { |
| this->validate(offsetInBytes); |
| void* p = SkTAddOffset<void>(fPtr, offsetInBytes); |
| Mark end{SkDEBUGCODE(fEnd)}; |
| SkDEBUGCODE(fEnd = Mark(p);) |
| return W{p, end}; |
| } |
| |
| void validate(size_t bytesToWrite) const { |
| // If the buffer writer had an end marked, make sure we're not crossing it. |
| // Ideally, all creators of BufferWriters mark the end, but a lot of legacy code is not set |
| // up to easily do this. |
| SkASSERT(fPtr || bytesToWrite == 0); |
| SkASSERT(!fEnd || Mark(fPtr, bytesToWrite) <= fEnd); |
| } |
| |
| protected: |
| void* fPtr = nullptr; |
| SkDEBUGCODE(mutable Mark fEnd = {};) |
| }; |
| |
| /** |
| * Helper for writing vertex data to a buffer. Usage: |
| * VertexWriter vertices{target->makeVertexSpace(...)}; |
| * vertices << A0 << B0 << C0 << ...; |
| * vertices << A1 << B1 << C1 << ...; |
| * |
| * Each value must be POD (plain old data), or have a specialization of the "<<" operator. |
| */ |
| struct VertexWriter : public BufferWriter { |
| inline constexpr static uint32_t kIEEE_32_infinity = 0x7f800000; |
| |
| VertexWriter() = default; |
| // DEPRECATED: Prefer specifying the size of the buffer being written to as well |
| explicit VertexWriter(void* ptr) : BufferWriter(ptr, Mark()) {} |
| |
| VertexWriter(void* ptr, size_t size) : BufferWriter(ptr, size) {} |
| VertexWriter(void* ptr, Mark end) : BufferWriter(ptr, end) {} |
| |
| VertexWriter(const VertexWriter&) = delete; |
| VertexWriter(VertexWriter&& that) { *this = std::move(that); } |
| |
| VertexWriter& operator=(const VertexWriter&) = delete; |
| VertexWriter& operator=(VertexWriter&& that) { |
| BufferWriter::operator=(std::move(that)); |
| return *this; |
| } |
| |
| VertexWriter makeOffset(size_t offsetInBytes) const { |
| return this->BufferWriter::makeOffset<VertexWriter>(offsetInBytes); |
| } |
| |
| template <typename T> |
| struct Conditional { |
| bool fCondition; |
| T fValue; |
| }; |
| |
| template <typename T> |
| static Conditional<T> If(bool condition, const T& value) { |
| return {condition, value}; |
| } |
| |
| template <typename T> |
| struct Skip {}; |
| |
| template<typename T> |
| struct ArrayDesc { |
| const T* fArray; |
| int fCount; |
| }; |
| |
| template <typename T> |
| static ArrayDesc<T> Array(const T* array, int count) { |
| return {array, count}; |
| } |
| |
| template<int kCount, typename T> |
| struct RepeatDesc { |
| const T& fVal; |
| }; |
| |
| template <int kCount, typename T> |
| static RepeatDesc<kCount, T> Repeat(const T& val) { |
| return {val}; |
| } |
| |
| /** |
| * Specialized utilities for writing a four-vertices, with some data being replicated at each |
| * vertex, and other data being the appropriate 2-components from an SkRect to construct a |
| * triangle strip. |
| * |
| * - Four sets of data will be written |
| * |
| * - For any arguments where is_quad<Type>::value is true, a unique point will be written at |
| * each vertex. To make a custom type be emitted as a quad, declare: |
| * |
| * template<> struct VertexWriter::is_quad<MyQuadClass> : std::true_type {}; |
| * |
| * and define: |
| * |
| * MyQuadClass::writeVertex(int cornerIdx, VertexWriter&) const { ... } |
| * |
| * - For any arguments where is_quad<Type>::value is false, its value will be replicated at each |
| * vertex. |
| */ |
| template <typename T> |
| struct is_quad : std::false_type {}; |
| |
| template <typename T> |
| struct TriStrip { |
| void writeVertex(int cornerIdx, VertexWriter& w) const { |
| switch (cornerIdx) { |
| case 0: w << l << t; return; |
| case 1: w << l << b; return; |
| case 2: w << r << t; return; |
| case 3: w << r << b; return; |
| } |
| SkUNREACHABLE; |
| } |
| T l, t, r, b; |
| }; |
| |
| static TriStrip<float> TriStripFromRect(const SkRect& r) { |
| return { r.fLeft, r.fTop, r.fRight, r.fBottom }; |
| } |
| |
| static TriStrip<uint16_t> TriStripFromUVs(const std::array<uint16_t, 4>& rect) { |
| return { rect[0], rect[1], rect[2], rect[3] }; |
| } |
| |
| template <typename T> |
| struct TriFan { |
| void writeVertex(int cornerIdx, VertexWriter& w) const { |
| switch (cornerIdx) { |
| case 0: w << l << t; return; |
| case 1: w << l << b; return; |
| case 2: w << r << b; return; |
| case 3: w << r << t; return; |
| } |
| SkUNREACHABLE; |
| } |
| T l, t, r, b; |
| }; |
| |
| static TriFan<float> TriFanFromRect(const SkRect& r) { |
| return { r.fLeft, r.fTop, r.fRight, r.fBottom }; |
| } |
| |
| template <typename... Args> |
| void writeQuad(const Args&... remainder) { |
| this->writeQuadVertex<0>(remainder...); |
| this->writeQuadVertex<1>(remainder...); |
| this->writeQuadVertex<2>(remainder...); |
| this->writeQuadVertex<3>(remainder...); |
| } |
| |
| private: |
| template <int kCornerIdx, typename T, typename... Args> |
| std::enable_if_t<!is_quad<T>::value, void> writeQuadVertex(const T& val, |
| const Args&... remainder) { |
| *this << val; // Non-quads duplicate their value. |
| this->writeQuadVertex<kCornerIdx>(remainder...); |
| } |
| |
| template <int kCornerIdx, typename Q, typename... Args> |
| std::enable_if_t<is_quad<Q>::value, void> writeQuadVertex(const Q& quad, |
| const Args&... remainder) { |
| quad.writeVertex(kCornerIdx, *this); // Quads emit a different corner each time. |
| this->writeQuadVertex<kCornerIdx>(remainder...); |
| } |
| |
| template <int kCornerIdx> |
| void writeQuadVertex() {} |
| |
| template <typename T> |
| friend VertexWriter& operator<<(VertexWriter&, const T&); |
| |
| template <typename T> |
| friend VertexWriter& operator<<(VertexWriter&, const ArrayDesc<T>&); |
| }; |
| |
| template <typename T> |
| inline VertexWriter& operator<<(VertexWriter& w, const T& val) { |
| static_assert(std::is_pod<T>::value, ""); |
| w.validate(sizeof(T)); |
| memcpy(w.fPtr, &val, sizeof(T)); |
| w = w.makeOffset(sizeof(T)); |
| return w; |
| } |
| |
| template <typename T> |
| inline VertexWriter& operator<<(VertexWriter& w, const VertexWriter::Conditional<T>& val) { |
| static_assert(std::is_pod<T>::value, ""); |
| if (val.fCondition) { |
| w << val.fValue; |
| } |
| return w; |
| } |
| |
| template <typename T> |
| inline VertexWriter& operator<<(VertexWriter& w, const VertexWriter::Skip<T>& val) { |
| w = w.makeOffset(sizeof(T)); |
| return w; |
| } |
| |
| template <typename T> |
| inline VertexWriter& operator<<(VertexWriter& w, const VertexWriter::ArrayDesc<T>& array) { |
| static_assert(std::is_pod<T>::value, ""); |
| w.validate(array.fCount * sizeof(T)); |
| memcpy(w.fPtr, array.fArray, array.fCount * sizeof(T)); |
| w = w.makeOffset(sizeof(T) * array.fCount); |
| return w; |
| } |
| |
| template <int kCount, typename T> |
| inline VertexWriter& operator<<(VertexWriter& w, const VertexWriter::RepeatDesc<kCount,T>& repeat) { |
| for (int i = 0; i < kCount; ++i) { |
| w << repeat.fVal; |
| } |
| return w; |
| } |
| |
| template <> |
| [[maybe_unused]] inline VertexWriter& operator<<(VertexWriter& w, const skvx::float4& vector) { |
| w.validate(sizeof(vector)); |
| vector.store(w.fPtr); |
| w = w.makeOffset(sizeof(vector)); |
| return w; |
| } |
| |
| // Allow r-value/temporary writers to be appended to |
| template <typename T> |
| inline VertexWriter& operator<<(VertexWriter&& w, const T& val) { return w << val; } |
| |
| template <typename T> |
| struct VertexWriter::is_quad<VertexWriter::TriStrip<T>> : std::true_type {}; |
| |
| template <typename T> |
| struct VertexWriter::is_quad<VertexWriter::TriFan<T>> : std::true_type {}; |
| |
| /** |
| * VertexColor is a helper for writing colors to a vertex buffer. It outputs either four bytes or |
| * or four float32 channels, depending on the wideColor parameter. Note that the GP needs to have |
| * been constructed with the correct attribute type for colors, to match the usage here. |
| */ |
| class VertexColor { |
| public: |
| VertexColor() = default; |
| |
| explicit VertexColor(const SkPMColor4f& color, bool wideColor) { |
| this->set(color, wideColor); |
| } |
| |
| void set(const SkPMColor4f& color, bool wideColor) { |
| if (wideColor) { |
| memcpy(fColor, color.vec(), sizeof(fColor)); |
| } else { |
| fColor[0] = color.toBytes_RGBA(); |
| } |
| fWideColor = wideColor; |
| } |
| |
| size_t size() const { return fWideColor ? 16 : 4; } |
| |
| private: |
| template <typename T> |
| friend VertexWriter& operator<<(VertexWriter&, const T&); |
| |
| uint32_t fColor[4]; |
| bool fWideColor; |
| }; |
| |
| template <> |
| [[maybe_unused]] inline VertexWriter& operator<<(VertexWriter& w, const VertexColor& color) { |
| w << color.fColor[0]; |
| if (color.fWideColor) { |
| w << color.fColor[1] |
| << color.fColor[2] |
| << color.fColor[3]; |
| } |
| return w; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////////// |
| |
| struct IndexWriter : public BufferWriter { |
| IndexWriter() = default; |
| |
| IndexWriter(void* ptr, size_t size) : BufferWriter(ptr, size) {} |
| IndexWriter(void* ptr, Mark end) : BufferWriter(ptr, end) {} |
| |
| IndexWriter(const IndexWriter&) = delete; |
| IndexWriter(IndexWriter&& that) { *this = std::move(that); } |
| |
| IndexWriter& operator=(const IndexWriter&) = delete; |
| IndexWriter& operator=(IndexWriter&& that) { |
| BufferWriter::operator=(std::move(that)); |
| return *this; |
| } |
| |
| IndexWriter makeOffset(int numIndices) const { |
| return this->BufferWriter::makeOffset<IndexWriter>(numIndices * sizeof(uint16_t)); |
| } |
| |
| void writeArray(const uint16_t* array, int count) { |
| size_t arraySize = count * sizeof(uint16_t); |
| this->validate(arraySize); |
| memcpy(fPtr, array, arraySize); |
| fPtr = SkTAddOffset<void>(fPtr, arraySize); |
| } |
| |
| friend IndexWriter& operator<<(IndexWriter& w, uint16_t val); |
| }; |
| |
| inline IndexWriter& operator<<(IndexWriter& w, uint16_t val) { |
| w.validate(sizeof(uint16_t)); |
| memcpy(w.fPtr, &val, sizeof(uint16_t)); |
| w = w.makeOffset(1); |
| return w; |
| } |
| |
| inline IndexWriter& operator<<(IndexWriter& w, int val) { return (w << SkTo<uint16_t>(val)); } |
| |
| template<typename T> |
| inline IndexWriter& operator<<(IndexWriter&& w, const T& val) { return w << val; } |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////////// |
| |
| struct UniformWriter : public BufferWriter { |
| UniformWriter() = default; |
| |
| UniformWriter(void* ptr, size_t size) : BufferWriter(ptr, size) {} |
| UniformWriter(void* ptr, Mark end) : BufferWriter(ptr, end) {} |
| |
| UniformWriter(const UniformWriter&) = delete; |
| UniformWriter(UniformWriter&& that) { *this = std::move(that); } |
| |
| UniformWriter& operator=(const UniformWriter&) = delete; |
| UniformWriter& operator=(UniformWriter&& that) { |
| BufferWriter::operator=(std::move(that)); |
| return *this; |
| } |
| |
| void write(const void* src, size_t bytes) { |
| this->validate(bytes); |
| memcpy(fPtr, src, bytes); |
| fPtr = SkTAddOffset<void>(fPtr, bytes); |
| } |
| void skipBytes(size_t bytes) { |
| this->validate(bytes); |
| fPtr = SkTAddOffset<void>(fPtr, bytes); |
| } |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////////// |
| |
| struct UploadWriter : public BufferWriter { |
| UploadWriter() = default; |
| |
| UploadWriter(void* ptr, size_t size) : BufferWriter(ptr, size) {} |
| |
| UploadWriter(const UploadWriter&) = delete; |
| UploadWriter(UploadWriter&& that) { *this = std::move(that); } |
| |
| UploadWriter& operator=(const UploadWriter&) = delete; |
| UploadWriter& operator=(UploadWriter&& that) { |
| BufferWriter::operator=(std::move(that)); |
| return *this; |
| } |
| |
| // Writes a block of image data to the upload buffer, starting at `offset`. The source image is |
| // `srcRowBytes` wide, and the written block is `dstRowBytes` wide and `rowCount` bytes tall. |
| void write(size_t offset, const void* src, size_t srcRowBytes, size_t dstRowBytes, |
| size_t trimRowBytes, int rowCount) { |
| this->validate(dstRowBytes * rowCount); |
| void* dst = SkTAddOffset<void>(fPtr, offset); |
| SkRectMemcpy(dst, dstRowBytes, src, srcRowBytes, trimRowBytes, rowCount); |
| } |
| |
| void convertAndWrite(size_t offset, |
| const SkImageInfo& srcInfo, const void* src, size_t srcRowBytes, |
| const SkImageInfo& dstInfo, size_t dstRowBytes) { |
| SkASSERT(srcInfo.width() == dstInfo.width() && srcInfo.height() == dstInfo.height()); |
| this->validate(dstRowBytes * dstInfo.height()); |
| void* dst = SkTAddOffset<void>(fPtr, offset); |
| SkAssertResult(SkConvertPixels(dstInfo, dst, dstRowBytes, srcInfo, src, srcRowBytes)); |
| } |
| }; |
| |
| } // namespace skgpu |
| |
| #endif // skgpu_BufferWriter_DEFINED |