1 /* 2 * Copyright 2016 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 SkNormalSourcePriv_DEFINED 9 #define SkNormalSourcePriv_DEFINED 10 11 #if SK_SUPPORT_GPU 12 #include "glsl/GrGLSLFragmentProcessor.h" 13 #include "glsl/GrGLSLFragmentShaderBuilder.h" 14 15 /* GLSLFragmentProcessors for NormalSourceImpls must sub-class this class and override onEmitCode, 16 * and setNormalData calls, as well as all other calls FPs normally override, except for the 2 17 * defined in this superclass. 18 * This class exists to intercept emitCode calls and emit <0, 0, 1> if the FP requires a distance 19 * vector but the GP doesn't provide it. onSetData calls need to be intercepted too because 20 * uniform handlers will be invalid in subclasses where onEmitCode isn't called. 21 * We don't need to adjust the key here since the use of a given GP (through its class ID already in 22 * the key), will determine what code gets emitted here. 23 */ 24 class GLSLNormalFP : public GrGLSLFragmentProcessor { 25 public: GLSLNormalFP()26 GLSLNormalFP() 27 : fDidIntercept(false) {} 28 emitCode(EmitArgs & args)29 void emitCode(EmitArgs& args) final override { 30 if (args.fFp.usesDistanceVectorField() && !args.fGpImplementsDistanceVector) { 31 GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder; 32 fragBuilder->codeAppendf("// GLSLNormalFP intercepted emitCode call, GP does not " 33 "implement required distance vector feature\n"); 34 fragBuilder->codeAppendf("%s = vec4(0, 0, 1, 0);", args.fOutputColor); 35 36 fDidIntercept = true; 37 } else { 38 this->onEmitCode(args); 39 } 40 } 41 onSetData(const GrGLSLProgramDataManager & pdman,const GrProcessor & proc)42 void onSetData(const GrGLSLProgramDataManager& pdman, const GrProcessor& proc) final override { 43 if (!fDidIntercept) { 44 this->setNormalData(pdman, proc); 45 } 46 } 47 48 protected: 49 virtual void onEmitCode(EmitArgs& args) = 0; 50 virtual void setNormalData(const GrGLSLProgramDataManager& pdman, const GrProcessor& proc) = 0; 51 52 private: 53 bool fDidIntercept; 54 }; 55 #endif 56 57 #endif 58