diff -r 000000000000 -r 6474c204b198 gfx/skia/trunk/src/effects/gradients/SkGradientShaderPriv.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/gfx/skia/trunk/src/effects/gradients/SkGradientShaderPriv.h Wed Dec 31 06:09:35 2014 +0100 @@ -0,0 +1,390 @@ +/* + * Copyright 2012 Google Inc. + * + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + */ + +#ifndef SkGradientShaderPriv_DEFINED +#define SkGradientShaderPriv_DEFINED + +#include "SkGradientShader.h" +#include "SkClampRange.h" +#include "SkColorPriv.h" +#include "SkReadBuffer.h" +#include "SkWriteBuffer.h" +#include "SkMallocPixelRef.h" +#include "SkUnitMapper.h" +#include "SkUtils.h" +#include "SkTemplates.h" +#include "SkBitmapCache.h" +#include "SkShader.h" + +static inline void sk_memset32_dither(uint32_t dst[], uint32_t v0, uint32_t v1, + int count) { + if (count > 0) { + if (v0 == v1) { + sk_memset32(dst, v0, count); + } else { + int pairs = count >> 1; + for (int i = 0; i < pairs; i++) { + *dst++ = v0; + *dst++ = v1; + } + if (count & 1) { + *dst = v0; + } + } + } +} + +// Clamp + +static inline SkFixed clamp_tileproc(SkFixed x) { + return SkClampMax(x, 0xFFFF); +} + +// Repeat + +static inline SkFixed repeat_tileproc(SkFixed x) { + return x & 0xFFFF; +} + +// Mirror + +// Visual Studio 2010 (MSC_VER=1600) optimizes bit-shift code incorrectly. +// See http://code.google.com/p/skia/issues/detail?id=472 +#if defined(_MSC_VER) && (_MSC_VER >= 1600) +#pragma optimize("", off) +#endif + +static inline SkFixed mirror_tileproc(SkFixed x) { + int s = x << 15 >> 31; + return (x ^ s) & 0xFFFF; +} + +#if defined(_MSC_VER) && (_MSC_VER >= 1600) +#pragma optimize("", on) +#endif + +/////////////////////////////////////////////////////////////////////////////// + +typedef SkFixed (*TileProc)(SkFixed); + +/////////////////////////////////////////////////////////////////////////////// + +static const TileProc gTileProcs[] = { + clamp_tileproc, + repeat_tileproc, + mirror_tileproc +}; + +/////////////////////////////////////////////////////////////////////////////// + +class SkGradientShaderBase : public SkShader { +public: + struct Descriptor { + Descriptor() { + sk_bzero(this, sizeof(*this)); + fTileMode = SkShader::kClamp_TileMode; + } + + const SkColor* fColors; + const SkScalar* fPos; + int fCount; + SkShader::TileMode fTileMode; + SkUnitMapper* fMapper; + uint32_t fFlags; + }; + +public: + SkGradientShaderBase(const Descriptor& desc); + virtual ~SkGradientShaderBase(); + + virtual bool setContext(const SkBitmap&, const SkPaint&, const SkMatrix&) SK_OVERRIDE; + virtual uint32_t getFlags() SK_OVERRIDE { return fFlags; } + virtual bool isOpaque() const SK_OVERRIDE; + + void getGradientTableBitmap(SkBitmap*) const; + + enum { + /// Seems like enough for visual accuracy. TODO: if pos[] deserves + /// it, use a larger cache. + kCache16Bits = 8, + kCache16Count = (1 << kCache16Bits), + kCache16Shift = 16 - kCache16Bits, + kSqrt16Shift = 8 - kCache16Bits, + + /// Seems like enough for visual accuracy. TODO: if pos[] deserves + /// it, use a larger cache. + kCache32Bits = 8, + kCache32Count = (1 << kCache32Bits), + kCache32Shift = 16 - kCache32Bits, + kSqrt32Shift = 8 - kCache32Bits, + + /// This value is used to *read* the dither cache; it may be 0 + /// if dithering is disabled. + kDitherStride32 = kCache32Count, + kDitherStride16 = kCache16Count, + }; + + +protected: + SkGradientShaderBase(SkReadBuffer& ); + virtual void flatten(SkWriteBuffer&) const SK_OVERRIDE; + SK_TO_STRING_OVERRIDE() + + SkUnitMapper* fMapper; + SkMatrix fPtsToUnit; // set by subclass + SkMatrix fDstToIndex; + SkMatrix::MapXYProc fDstToIndexProc; + TileMode fTileMode; + TileProc fTileProc; + int fColorCount; + uint8_t fDstToIndexClass; + uint8_t fFlags; + uint8_t fGradFlags; + + struct Rec { + SkFixed fPos; // 0...1 + uint32_t fScale; // (1 << 24) / range + }; + Rec* fRecs; + + const uint16_t* getCache16() const; + const SkPMColor* getCache32() const; + + void commonAsAGradient(GradientInfo*) const; + +private: + enum { + kColorStorageCount = 4, // more than this many colors, and we'll use sk_malloc for the space + + kStorageSize = kColorStorageCount * (sizeof(SkColor) + sizeof(Rec)) + }; + SkColor fStorage[(kStorageSize + 3) >> 2]; + SkColor* fOrigColors; // original colors, before modulation by paint in setContext + bool fColorsAreOpaque; + + mutable uint16_t* fCache16; // working ptr. If this is NULL, we need to recompute the cache values + mutable SkPMColor* fCache32; // working ptr. If this is NULL, we need to recompute the cache values + + mutable uint16_t* fCache16Storage; // storage for fCache16, allocated on demand + mutable SkMallocPixelRef* fCache32PixelRef; + mutable unsigned fCacheAlpha; // the alpha value we used when we computed the cache. larger than 8bits so we can store uninitialized value + + static void Build16bitCache(uint16_t[], SkColor c0, SkColor c1, int count); + static void Build32bitCache(SkPMColor[], SkColor c0, SkColor c1, int count, + U8CPU alpha, uint32_t gradFlags); + void setCacheAlpha(U8CPU alpha) const; + void initCommon(); + + typedef SkShader INHERITED; +}; + +static inline int init_dither_toggle(int x, int y) { + x &= 1; + y = (y & 1) << 1; + return (x | y) * SkGradientShaderBase::kDitherStride32; +} + +static inline int next_dither_toggle(int toggle) { + return toggle ^ SkGradientShaderBase::kDitherStride32; +} + +static inline int init_dither_toggle16(int x, int y) { + return ((x ^ y) & 1) * SkGradientShaderBase::kDitherStride16; +} + +static inline int next_dither_toggle16(int toggle) { + return toggle ^ SkGradientShaderBase::kDitherStride16; +} + +/////////////////////////////////////////////////////////////////////////////// + +#if SK_SUPPORT_GPU + +#include "GrCoordTransform.h" +#include "gl/GrGLEffect.h" + +class GrEffectStage; +class GrBackendEffectFactory; + +/* + * The interpretation of the texture matrix depends on the sample mode. The + * texture matrix is applied both when the texture coordinates are explicit + * and when vertex positions are used as texture coordinates. In the latter + * case the texture matrix is applied to the pre-view-matrix position + * values. + * + * Normal SampleMode + * The post-matrix texture coordinates are in normalize space with (0,0) at + * the top-left and (1,1) at the bottom right. + * RadialGradient + * The matrix specifies the radial gradient parameters. + * (0,0) in the post-matrix space is center of the radial gradient. + * Radial2Gradient + * Matrix transforms to space where first circle is centered at the + * origin. The second circle will be centered (x, 0) where x may be + * 0 and is provided by setRadial2Params. The post-matrix space is + * normalized such that 1 is the second radius - first radius. + * SweepGradient + * The angle from the origin of texture coordinates in post-matrix space + * determines the gradient value. + */ + + class GrTextureStripAtlas; + +// Base class for Gr gradient effects +class GrGradientEffect : public GrEffect { +public: + + GrGradientEffect(GrContext* ctx, + const SkGradientShaderBase& shader, + const SkMatrix& matrix, + SkShader::TileMode tileMode); + + virtual ~GrGradientEffect(); + + bool useAtlas() const { return SkToBool(-1 != fRow); } + SkScalar getYCoord() const { return fYCoord; }; + + virtual void getConstantColorComponents(GrColor* color, uint32_t* validFlags) const SK_OVERRIDE; + + enum ColorType { + kTwo_ColorType, + kThree_ColorType, + kTexture_ColorType + }; + + ColorType getColorType() const { return fColorType; } + + enum PremulType { + kBeforeInterp_PremulType, + kAfterInterp_PremulType, + }; + + PremulType getPremulType() const { return fPremulType; } + + const SkColor* getColors(int pos) const { + SkASSERT(fColorType != kTexture_ColorType); + SkASSERT((pos-1) <= fColorType); + return &fColors[pos]; + } + +protected: + + /** Populates a pair of arrays with colors and stop info to construct a random gradient. + The function decides whether stop values should be used or not. The return value indicates + the number of colors, which will be capped by kMaxRandomGradientColors. colors should be + sized to be at least kMaxRandomGradientColors. stops is a pointer to an array of at least + size kMaxRandomGradientColors. It may be updated to NULL, indicating that NULL should be + passed to the gradient factory rather than the array. + */ + static const int kMaxRandomGradientColors = 4; + static int RandomGradientParams(SkRandom* r, + SkColor colors[kMaxRandomGradientColors], + SkScalar** stops, + SkShader::TileMode* tm); + + virtual bool onIsEqual(const GrEffect& effect) const SK_OVERRIDE; + + const GrCoordTransform& getCoordTransform() const { return fCoordTransform; } + +private: + static const GrCoordSet kCoordSet = kLocal_GrCoordSet; + + enum { + kMaxAnalyticColors = 3 // if more colors use texture + }; + + GrCoordTransform fCoordTransform; + GrTextureAccess fTextureAccess; + SkScalar fYCoord; + GrTextureStripAtlas* fAtlas; + int fRow; + bool fIsOpaque; + ColorType fColorType; + SkColor fColors[kMaxAnalyticColors]; + PremulType fPremulType; // This only changes behavior for two and three color special cases. + // It is already baked into to the table for texture gradients. + typedef GrEffect INHERITED; + +}; + +/////////////////////////////////////////////////////////////////////////////// + +// Base class for GL gradient effects +class GrGLGradientEffect : public GrGLEffect { +public: + GrGLGradientEffect(const GrBackendEffectFactory& factory); + virtual ~GrGLGradientEffect(); + + virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE; + +protected: + enum { + kPremulTypeKeyBitCnt = 1, + kPremulTypeMask = 1, + kPremulBeforeInterpKey = kPremulTypeMask, + + kTwoColorKey = 2 << kPremulTypeKeyBitCnt, + kThreeColorKey = 3 << kPremulTypeKeyBitCnt, + kColorKeyMask = kTwoColorKey | kThreeColorKey, + kColorKeyBitCnt = 2, + + // Subclasses must shift any key bits they produce up by this amount + // and combine with the result of GenBaseGradientKey. + kBaseKeyBitCnt = (kPremulTypeKeyBitCnt + kColorKeyBitCnt) + }; + + static GrGradientEffect::ColorType ColorTypeFromKey(EffectKey key){ + if (kTwoColorKey == (key & kColorKeyMask)) { + return GrGradientEffect::kTwo_ColorType; + } else if (kThreeColorKey == (key & kColorKeyMask)) { + return GrGradientEffect::kThree_ColorType; + } else {return GrGradientEffect::kTexture_ColorType;} + } + + static GrGradientEffect::PremulType PremulTypeFromKey(EffectKey key){ + if (kPremulBeforeInterpKey == (key & kPremulTypeMask)) { + return GrGradientEffect::kBeforeInterp_PremulType; + } else { + return GrGradientEffect::kAfterInterp_PremulType; + } + } + + /** + * Subclasses must call this. It will return a value restricted to the lower kBaseKeyBitCnt + * bits. + */ + static EffectKey GenBaseGradientKey(const GrDrawEffect&); + + // Emits the uniform used as the y-coord to texture samples in derived classes. Subclasses + // should call this method from their emitCode(). + void emitUniforms(GrGLShaderBuilder* builder, EffectKey key); + + + // emit code that gets a fragment's color from an expression for t; Has branches for 3 separate + // control flows inside -- 2 color gradients, 3 color symmetric gradients (both using + // native GLSL mix), and 4+ color gradients that use the traditional texture lookup. + void emitColor(GrGLShaderBuilder* builder, + const char* gradientTValue, + EffectKey key, + const char* outputColor, + const char* inputColor, + const TextureSamplerArray& samplers); + +private: + SkScalar fCachedYCoord; + GrGLUniformManager::UniformHandle fFSYUni; + GrGLUniformManager::UniformHandle fColorStartUni; + GrGLUniformManager::UniformHandle fColorMidUni; + GrGLUniformManager::UniformHandle fColorEndUni; + + typedef GrGLEffect INHERITED; +}; + +#endif + +#endif