1 /*
2  * Copyright 2014 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 #include "GrGLSLGeometryProcessor.h"
9 
10 #include "GrCoordTransform.h"
11 #include "glsl/GrGLSLFragmentShaderBuilder.h"
12 #include "glsl/GrGLSLUniformHandler.h"
13 #include "glsl/GrGLSLVarying.h"
14 #include "glsl/GrGLSLVertexShaderBuilder.h"
15 
emitCode(EmitArgs & args)16 void GrGLSLGeometryProcessor::emitCode(EmitArgs& args) {
17     GrGLSLVertexBuilder* vBuilder = args.fVertBuilder;
18     GrGPArgs gpArgs;
19     this->onEmitCode(args, &gpArgs);
20     vBuilder->transformToNormalizedDeviceSpace(gpArgs.fPositionVar, args.fRTAdjustName);
21     if (kVec2f_GrSLType == gpArgs.fPositionVar.getType()) {
22         args.fVaryingHandler->setNoPerspective();
23     }
24 }
25 
emitTransforms(GrGLSLVertexBuilder * vb,GrGLSLVaryingHandler * varyingHandler,GrGLSLUniformHandler * uniformHandler,const GrShaderVar & posVar,const char * localCoords,const SkMatrix & localMatrix,FPCoordTransformHandler * handler)26 void GrGLSLGeometryProcessor::emitTransforms(GrGLSLVertexBuilder* vb,
27                                              GrGLSLVaryingHandler* varyingHandler,
28                                              GrGLSLUniformHandler* uniformHandler,
29                                              const GrShaderVar& posVar,
30                                              const char* localCoords,
31                                              const SkMatrix& localMatrix,
32                                              FPCoordTransformHandler* handler) {
33     int i = 0;
34     while (const GrCoordTransform* coordTransform = handler->nextCoordTransform()) {
35         SkString strUniName;
36         strUniName.printf("CoordTransformMatrix_%d", i);
37         GrSLType varyingType;
38 
39         uint32_t type = coordTransform->getMatrix().getType();
40         type |= localMatrix.getType();
41 
42         varyingType = SkToBool(SkMatrix::kPerspective_Mask & type) ? kVec3f_GrSLType :
43                                                                      kVec2f_GrSLType;
44         GrSLPrecision precision = coordTransform->precision();
45 
46         const char* uniName;
47 
48 
49         fInstalledTransforms.push_back().fHandle = uniformHandler->addUniform(kVertex_GrShaderFlag,
50                                                                               kMat33f_GrSLType,
51                                                                               precision,
52                                                                               strUniName.c_str(),
53                                                                               &uniName).toIndex();
54         SkString strVaryingName;
55         strVaryingName.printf("TransformedCoords_%d", i);
56 
57         GrGLSLVertToFrag v(varyingType);
58         varyingHandler->addVarying(strVaryingName.c_str(), &v, precision);
59 
60         SkASSERT(kVec2f_GrSLType == varyingType || kVec3f_GrSLType == varyingType);
61         handler->specifyCoordsForCurrCoordTransform(SkString(v.fsIn()), varyingType);
62 
63         if (kVec2f_GrSLType == varyingType) {
64             vb->codeAppendf("%s = (%s * vec3(%s, 1)).xy;", v.vsOut(), uniName, localCoords);
65         } else {
66             vb->codeAppendf("%s = %s * vec3(%s, 1);", v.vsOut(), uniName, localCoords);
67         }
68         ++i;
69     }
70 }
71 
setTransformDataHelper(const SkMatrix & localMatrix,const GrGLSLProgramDataManager & pdman,FPCoordTransformIter * transformIter)72 void GrGLSLGeometryProcessor::setTransformDataHelper(const SkMatrix& localMatrix,
73                                                      const GrGLSLProgramDataManager& pdman,
74                                                      FPCoordTransformIter* transformIter) {
75     int i = 0;
76     while (const GrCoordTransform* coordTransform = transformIter->next()) {
77         const SkMatrix& m = GetTransformMatrix(localMatrix, *coordTransform);
78         if (!fInstalledTransforms[i].fCurrentValue.cheapEqualTo(m)) {
79             pdman.setSkMatrix(fInstalledTransforms[i].fHandle.toIndex(), m);
80             fInstalledTransforms[i].fCurrentValue = m;
81         }
82         ++i;
83     }
84     SkASSERT(i == fInstalledTransforms.count());
85 }
86 
setupPosition(GrGLSLVertexBuilder * vertBuilder,GrGPArgs * gpArgs,const char * posName)87 void GrGLSLGeometryProcessor::setupPosition(GrGLSLVertexBuilder* vertBuilder,
88                                             GrGPArgs* gpArgs,
89                                             const char* posName) {
90     gpArgs->fPositionVar.set(kVec2f_GrSLType, "pos2");
91     vertBuilder->codeAppendf("vec2 %s = %s;", gpArgs->fPositionVar.c_str(), posName);
92 }
93 
setupPosition(GrGLSLVertexBuilder * vertBuilder,GrGLSLUniformHandler * uniformHandler,GrGPArgs * gpArgs,const char * posName,const SkMatrix & mat,UniformHandle * viewMatrixUniform)94 void GrGLSLGeometryProcessor::setupPosition(GrGLSLVertexBuilder* vertBuilder,
95                                             GrGLSLUniformHandler* uniformHandler,
96                                             GrGPArgs* gpArgs,
97                                             const char* posName,
98                                             const SkMatrix& mat,
99                                             UniformHandle* viewMatrixUniform) {
100     if (mat.isIdentity()) {
101         gpArgs->fPositionVar.set(kVec2f_GrSLType, "pos2");
102         vertBuilder->codeAppendf("vec2 %s = %s;", gpArgs->fPositionVar.c_str(), posName);
103     } else {
104         const char* viewMatrixName;
105         *viewMatrixUniform = uniformHandler->addUniform(kVertex_GrShaderFlag,
106                                                         kMat33f_GrSLType, kHigh_GrSLPrecision,
107                                                         "uViewM",
108                                                         &viewMatrixName);
109         if (!mat.hasPerspective()) {
110             gpArgs->fPositionVar.set(kVec2f_GrSLType, "pos2");
111             vertBuilder->codeAppendf("vec2 %s = (%s * vec3(%s, 1)).xy;",
112                                      gpArgs->fPositionVar.c_str(), viewMatrixName, posName);
113         } else {
114             gpArgs->fPositionVar.set(kVec3f_GrSLType, "pos3");
115             vertBuilder->codeAppendf("vec3 %s = %s * vec3(%s, 1);",
116                                      gpArgs->fPositionVar.c_str(), viewMatrixName, posName);
117         }
118     }
119 }
120