1/* 2 * Copyright 2007 The Android Open Source Project 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8#ifndef SkColorShader_DEFINED 9#define SkColorShader_DEFINED 10 11#include "SkShader.h" 12 13/** \class SkColorShader 14 A Shader that represents a single color. In general, this effect can be 15 accomplished by just using the color field on the paint, but if an 16 actual shader object is needed, this provides that feature. 17*/ 18class SK_API SkColorShader : public SkShader { 19public: 20 /** Create a ColorShader that ignores the color in the paint, and uses the 21 specified color. Note: like all shaders, at draw time the paint's alpha 22 will be respected, and is applied to the specified color. 23 */ 24 explicit SkColorShader(SkColor c); 25 26 virtual bool isOpaque() const SK_OVERRIDE; 27 28 virtual size_t contextSize() const SK_OVERRIDE { 29 return sizeof(ColorShaderContext); 30 } 31 32 class ColorShaderContext : public SkShader::Context { 33 public: 34 ColorShaderContext(const SkColorShader& shader, const ContextRec&); 35 36 virtual uint32_t getFlags() const SK_OVERRIDE; 37 virtual uint8_t getSpan16Alpha() const SK_OVERRIDE; 38 virtual void shadeSpan(int x, int y, SkPMColor span[], int count) SK_OVERRIDE; 39 virtual void shadeSpan16(int x, int y, uint16_t span[], int count) SK_OVERRIDE; 40 virtual void shadeSpanAlpha(int x, int y, uint8_t alpha[], int count) SK_OVERRIDE; 41 42 private: 43 SkPMColor fPMColor; 44 uint32_t fFlags; 45 uint16_t fColor16; 46 47 typedef SkShader::Context INHERITED; 48 }; 49 50 // we return false for this, use asAGradient 51 virtual BitmapType asABitmap(SkBitmap* outTexture, 52 SkMatrix* outMatrix, 53 TileMode xy[2]) const SK_OVERRIDE; 54 55 virtual GradientType asAGradient(GradientInfo* info) const SK_OVERRIDE; 56 57 virtual bool asFragmentProcessor(GrContext*, const SkPaint&, const SkMatrix*, GrColor*, 58 GrFragmentProcessor**) const SK_OVERRIDE; 59 60 SK_TO_STRING_OVERRIDE() 61 SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkColorShader) 62 63protected: 64 SkColorShader(SkReadBuffer&); 65 virtual void flatten(SkWriteBuffer&) const SK_OVERRIDE; 66 virtual Context* onCreateContext(const ContextRec&, void* storage) const SK_OVERRIDE; 67 virtual bool onAsLuminanceColor(SkColor* lum) const SK_OVERRIDE { 68 *lum = fColor; 69 return true; 70 } 71 72private: 73 SkColor fColor; 74 75 typedef SkShader INHERITED; 76}; 77 78#endif 79