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 "glsl/GrGLSLProgramDataManager.h" 12 #include "glsl/GrGLSLTextureSampler.h" 13 14 class GrXferProcessor; 15 class GrGLSLCaps; 16 class GrGLSLUniformHandler; 17 class GrGLSLXPBuilder; 18 class GrGLSLXPFragmentBuilder; 19 20 class GrGLSLXferProcessor { 21 public: GrGLSLXferProcessor()22 GrGLSLXferProcessor() {} ~GrGLSLXferProcessor()23 virtual ~GrGLSLXferProcessor() {} 24 25 typedef GrGLSLTextureSampler::TextureSamplerArray TextureSamplerArray; 26 struct EmitArgs { EmitArgsEmitArgs27 EmitArgs(GrGLSLXPFragmentBuilder* fragBuilder, 28 GrGLSLUniformHandler* uniformHandler, 29 const GrGLSLCaps* caps, 30 const GrXferProcessor& xp, 31 const char* inputColor, 32 const char* inputCoverage, 33 const char* outputPrimary, 34 const char* outputSecondary, 35 const TextureSamplerArray& samplers, 36 const bool usePLSDstRead) 37 : fXPFragBuilder(fragBuilder) 38 , fUniformHandler(uniformHandler) 39 , fGLSLCaps(caps) 40 , fXP(xp) 41 , fInputColor(inputColor) 42 , fInputCoverage(inputCoverage) 43 , fOutputPrimary(outputPrimary) 44 , fOutputSecondary(outputSecondary) 45 , fSamplers(samplers) 46 , fUsePLSDstRead(usePLSDstRead) {} 47 48 GrGLSLXPFragmentBuilder* fXPFragBuilder; 49 GrGLSLUniformHandler* fUniformHandler; 50 const GrGLSLCaps* fGLSLCaps; 51 const GrXferProcessor& fXP; 52 const char* fInputColor; 53 const char* fInputCoverage; 54 const char* fOutputPrimary; 55 const char* fOutputSecondary; 56 const TextureSamplerArray& fSamplers; 57 bool fUsePLSDstRead; 58 }; 59 /** 60 * This is similar to emitCode() in the base class, except it takes a full shader builder. 61 * This allows the effect subclass to emit vertex code. 62 */ 63 void emitCode(const EmitArgs&); 64 65 /** A GrGLSLXferProcessor instance can be reused with any GrGLSLXferProcessor that produces 66 the same stage key; this function reads data from a GrGLSLXferProcessor and uploads any 67 uniform variables required by the shaders created in emitCode(). The GrXferProcessor 68 parameter is guaranteed to be of the same type that created this GrGLSLXferProcessor and 69 to have an identical processor key as the one that created this GrGLSLXferProcessor. This 70 function calls onSetData on the subclass of GrGLSLXferProcessor 71 */ 72 void setData(const GrGLSLProgramDataManager& pdm, const GrXferProcessor& xp); 73 74 protected: 75 static void DefaultCoverageModulation(GrGLSLXPFragmentBuilder* fragBuilder, 76 const char* srcCoverage, 77 const char* dstColor, 78 const char* outColor, 79 const char* outColorSecondary, 80 const GrXferProcessor& proc); 81 82 private: 83 /** 84 * Called by emitCode() when the XP will not be performing a dst read. This method is 85 * responsible for both blending and coverage. A subclass only needs to implement this method if 86 * it can construct a GrXferProcessor that will not read the dst color. 87 */ emitOutputsForBlendState(const EmitArgs &)88 virtual void emitOutputsForBlendState(const EmitArgs&) { 89 SkFAIL("emitOutputsForBlendState not implemented."); 90 } 91 92 /** 93 * Called by emitCode() when the XP will perform a dst read. This method only needs to supply 94 * the blending logic. The base class applies coverage. A subclass only needs to implement this 95 * method if it can construct a GrXferProcessor that reads the dst color. 96 */ emitBlendCodeForDstRead(GrGLSLXPFragmentBuilder *,GrGLSLUniformHandler *,const char * srcColor,const char * srcCoverage,const char * dstColor,const char * outColor,const char * outColorSecondary,const GrXferProcessor &)97 virtual void emitBlendCodeForDstRead(GrGLSLXPFragmentBuilder*, 98 GrGLSLUniformHandler*, 99 const char* srcColor, 100 const char* srcCoverage, 101 const char* dstColor, 102 const char* outColor, 103 const char* outColorSecondary, 104 const GrXferProcessor&) { 105 SkFAIL("emitBlendCodeForDstRead not implemented."); 106 } 107 108 virtual void onSetData(const GrGLSLProgramDataManager&, const GrXferProcessor&) = 0; 109 110 GrGLSLProgramDataManager::UniformHandle fDstTopLeftUni; 111 GrGLSLProgramDataManager::UniformHandle fDstScaleUni; 112 }; 113 #endif 114