1 /* 2 * Copyright 2015 Google Inc. 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 GrGLSLXferProcessor_DEFINED 9 #define GrGLSLXferProcessor_DEFINED 10 11 #include "include/core/SkPoint.h" 12 #include "src/gpu/glsl/GrGLSLProgramDataManager.h" 13 #include "src/gpu/glsl/GrGLSLUniformHandler.h" 14 15 class GrXferProcessor; 16 class GrGLSLXPBuilder; 17 class GrGLSLXPFragmentBuilder; 18 class GrShaderCaps; 19 class GrTexture; 20 21 class GrGLSLXferProcessor { 22 public: GrGLSLXferProcessor()23 GrGLSLXferProcessor() {} ~GrGLSLXferProcessor()24 virtual ~GrGLSLXferProcessor() {} 25 26 using SamplerHandle = GrGLSLUniformHandler::SamplerHandle; 27 28 struct EmitArgs { EmitArgsEmitArgs29 EmitArgs(GrGLSLXPFragmentBuilder* fragBuilder, 30 GrGLSLUniformHandler* uniformHandler, 31 const GrShaderCaps* caps, 32 const GrXferProcessor& xp, 33 const char* inputColor, 34 const char* inputCoverage, 35 const char* outputPrimary, 36 const char* outputSecondary, 37 const SamplerHandle dstTextureSamplerHandle, 38 GrSurfaceOrigin dstTextureOrigin, 39 uint16_t outputSwizzleKey) 40 : fXPFragBuilder(fragBuilder) 41 , fUniformHandler(uniformHandler) 42 , fShaderCaps(caps) 43 , fXP(xp) 44 , fInputColor(inputColor ? inputColor : "half4(1.0)") 45 , fInputCoverage(inputCoverage) 46 , fOutputPrimary(outputPrimary) 47 , fOutputSecondary(outputSecondary) 48 , fDstTextureSamplerHandle(dstTextureSamplerHandle) 49 , fDstTextureOrigin(dstTextureOrigin) { 50 fOutputSwizzle.setFromKey(outputSwizzleKey); 51 } 52 GrGLSLXPFragmentBuilder* fXPFragBuilder; 53 GrGLSLUniformHandler* fUniformHandler; 54 const GrShaderCaps* fShaderCaps; 55 const GrXferProcessor& fXP; 56 const char* fInputColor; 57 const char* fInputCoverage; 58 const char* fOutputPrimary; 59 const char* fOutputSecondary; 60 const SamplerHandle fDstTextureSamplerHandle; 61 GrSurfaceOrigin fDstTextureOrigin; 62 GrSwizzle fOutputSwizzle; 63 }; 64 /** 65 * This is similar to emitCode() in the base class, except it takes a full shader builder. 66 * This allows the effect subclass to emit vertex code. 67 */ 68 void emitCode(const EmitArgs&); 69 70 /** A GrGLSLXferProcessor instance can be reused with any GrGLSLXferProcessor that produces 71 the same stage key; this function reads data from a GrGLSLXferProcessor and uploads any 72 uniform variables required by the shaders created in emitCode(). The GrXferProcessor 73 parameter is guaranteed to be of the same type that created this GrGLSLXferProcessor and 74 to have an identical processor key as the one that created this GrGLSLXferProcessor. This 75 function calls onSetData on the subclass of GrGLSLXferProcessor 76 */ 77 void setData(const GrGLSLProgramDataManager& pdm, const GrXferProcessor& xp, 78 const GrTexture* dstTexture, const SkIPoint& dstTextureOffset); 79 80 protected: 81 static void DefaultCoverageModulation(GrGLSLXPFragmentBuilder* fragBuilder, 82 const char* srcCoverage, 83 const char* dstColor, 84 const char* outColor, 85 const char* outColorSecondary, 86 const GrXferProcessor& proc); 87 88 private: 89 /** 90 * Called by emitCode() when the XP will not be performing a dst read. This method is 91 * responsible for both blending and coverage. A subclass only needs to implement this method if 92 * it can construct a GrXferProcessor that will not read the dst color. 93 */ emitOutputsForBlendState(const EmitArgs &)94 virtual void emitOutputsForBlendState(const EmitArgs&) { 95 SK_ABORT("emitOutputsForBlendState not implemented."); 96 } 97 98 /** 99 * Called by emitCode() when the XP will perform a dst read. This method only needs to supply 100 * the blending logic. The base class applies coverage. A subclass only needs to implement this 101 * method if it can construct a GrXferProcessor that reads the dst color. 102 */ emitBlendCodeForDstRead(GrGLSLXPFragmentBuilder *,GrGLSLUniformHandler *,const char * srcColor,const char * srcCoverage,const char * dstColor,const char * outColor,const char * outColorSecondary,const GrXferProcessor &)103 virtual void emitBlendCodeForDstRead(GrGLSLXPFragmentBuilder*, 104 GrGLSLUniformHandler*, 105 const char* srcColor, 106 const char* srcCoverage, 107 const char* dstColor, 108 const char* outColor, 109 const char* outColorSecondary, 110 const GrXferProcessor&) { 111 SK_ABORT("emitBlendCodeForDstRead not implemented."); 112 } 113 114 virtual void emitOutputSwizzle(GrGLSLXPFragmentBuilder*, 115 const GrSwizzle&, 116 const char* outColor, 117 const char* outColorSecondary) const; 118 119 virtual void onSetData(const GrGLSLProgramDataManager&, const GrXferProcessor&) = 0; 120 121 GrGLSLProgramDataManager::UniformHandle fDstTopLeftUni; 122 GrGLSLProgramDataManager::UniformHandle fDstScaleUni; 123 }; 124 #endif 125