diff -r 000000000000 -r 6474c204b198 gfx/skia/trunk/include/core/SkMask.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/gfx/skia/trunk/include/core/SkMask.h Wed Dec 31 06:09:35 2014 +0100 @@ -0,0 +1,162 @@ + +/* + * Copyright 2006 The Android Open Source Project + * + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + */ + + +#ifndef SkMask_DEFINED +#define SkMask_DEFINED + +#include "SkRect.h" + +/** \class SkMask + SkMask is used to describe alpha bitmaps, either 1bit, 8bit, or + the 3-channel 3D format. These are passed to SkMaskFilter objects. +*/ +struct SkMask { + enum Format { + kBW_Format, //!< 1bit per pixel mask (e.g. monochrome) + kA8_Format, //!< 8bits per pixel mask (e.g. antialiasing) + k3D_Format, //!< 3 8bit per pixl planes: alpha, mul, add + kARGB32_Format, //!< SkPMColor + kLCD16_Format, //!< 565 alpha for r/g/b + kLCD32_Format //!< 888 alpha for r/g/b + }; + + enum { + kCountMaskFormats = kLCD32_Format + 1 + }; + + uint8_t* fImage; + SkIRect fBounds; + uint32_t fRowBytes; + Format fFormat; + + /** Returns true if the mask is empty: i.e. it has an empty bounds. + */ + bool isEmpty() const { return fBounds.isEmpty(); } + + /** Return the byte size of the mask, assuming only 1 plane. + Does not account for k3D_Format. For that, use computeTotalImageSize(). + If there is an overflow of 32bits, then returns 0. + */ + size_t computeImageSize() const; + + /** Return the byte size of the mask, taking into account + any extra planes (e.g. k3D_Format). + If there is an overflow of 32bits, then returns 0. + */ + size_t computeTotalImageSize() const; + + /** Returns the address of the byte that holds the specified bit. + Asserts that the mask is kBW_Format, and that x,y are in range. + x,y are in the same coordiate space as fBounds. + */ + uint8_t* getAddr1(int x, int y) const { + SkASSERT(kBW_Format == fFormat); + SkASSERT(fBounds.contains(x, y)); + SkASSERT(fImage != NULL); + return fImage + ((x - fBounds.fLeft) >> 3) + (y - fBounds.fTop) * fRowBytes; + } + + /** Returns the address of the specified byte. + Asserts that the mask is kA8_Format, and that x,y are in range. + x,y are in the same coordiate space as fBounds. + */ + uint8_t* getAddr8(int x, int y) const { + SkASSERT(kA8_Format == fFormat); + SkASSERT(fBounds.contains(x, y)); + SkASSERT(fImage != NULL); + return fImage + x - fBounds.fLeft + (y - fBounds.fTop) * fRowBytes; + } + + /** + * Return the address of the specified 16bit mask. In the debug build, + * this asserts that the mask's format is kLCD16_Format, and that (x,y) + * are contained in the mask's fBounds. + */ + uint16_t* getAddrLCD16(int x, int y) const { + SkASSERT(kLCD16_Format == fFormat); + SkASSERT(fBounds.contains(x, y)); + SkASSERT(fImage != NULL); + uint16_t* row = (uint16_t*)(fImage + (y - fBounds.fTop) * fRowBytes); + return row + (x - fBounds.fLeft); + } + + /** + * Return the address of the specified 32bit mask. In the debug build, + * this asserts that the mask's format is kLCD32_Format, and that (x,y) + * are contained in the mask's fBounds. + */ + uint32_t* getAddrLCD32(int x, int y) const { + SkASSERT(kLCD32_Format == fFormat); + SkASSERT(fBounds.contains(x, y)); + SkASSERT(fImage != NULL); + uint32_t* row = (uint32_t*)(fImage + (y - fBounds.fTop) * fRowBytes); + return row + (x - fBounds.fLeft); + } + + /** + * Return the address of the specified 32bit mask. In the debug build, + * this asserts that the mask's format is 32bits, and that (x,y) + * are contained in the mask's fBounds. + */ + uint32_t* getAddr32(int x, int y) const { + SkASSERT(kLCD32_Format == fFormat || kARGB32_Format == fFormat); + SkASSERT(fBounds.contains(x, y)); + SkASSERT(fImage != NULL); + uint32_t* row = (uint32_t*)(fImage + (y - fBounds.fTop) * fRowBytes); + return row + (x - fBounds.fLeft); + } + + /** + * Returns the address of the specified pixel, computing the pixel-size + * at runtime based on the mask format. This will be slightly slower than + * using one of the routines where the format is implied by the name + * e.g. getAddr8 or getAddrLCD32. + * + * x,y must be contained by the mask's bounds (this is asserted in the + * debug build, but not checked in the release build.) + * + * This should not be called with kBW_Format, as it will give unspecified + * results (and assert in the debug build). + */ + void* getAddr(int x, int y) const; + + static uint8_t* AllocImage(size_t bytes); + static void FreeImage(void* image); + + enum CreateMode { + kJustComputeBounds_CreateMode, //!< compute bounds and return + kJustRenderImage_CreateMode, //!< render into preallocate mask + kComputeBoundsAndRenderImage_CreateMode //!< compute bounds, alloc image and render into it + }; +}; + +/////////////////////////////////////////////////////////////////////////////// + +/** + * \class SkAutoMaskImage + * + * Stack class used to manage the fImage buffer in a SkMask. + * When this object loses scope, the buffer is freed with SkMask::FreeImage(). + */ +class SkAutoMaskFreeImage { +public: + SkAutoMaskFreeImage(uint8_t* maskImage) { + fImage = maskImage; + } + + ~SkAutoMaskFreeImage() { + SkMask::FreeImage(fImage); + } + +private: + uint8_t* fImage; +}; +#define SkAutoMaskFreeImage(...) SK_REQUIRE_LOCAL_VAR(SkAutoMaskFreeImage) + +#endif