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      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 "GrGLGeometryProcessor.h"
      9 
     10 #include "builders/GrGLProgramBuilder.h"
     11 
     12 void GrGLGeometryProcessor::emitCode(EmitArgs& args) {
     13     GrGLVertexBuilder* vsBuilder = args.fPB->getVertexShaderBuilder();
     14     GrGPArgs gpArgs;
     15     this->onEmitCode(args, &gpArgs);
     16     vsBuilder->transformToNormalizedDeviceSpace(gpArgs.fPositionVar);
     17 }
     18 
     19 void GrGLGeometryProcessor::emitTransforms(GrGLGPBuilder* pb,
     20                                            const GrShaderVar& posVar,
     21                                            const char* localCoords,
     22                                            const SkMatrix& localMatrix,
     23                                            const TransformsIn& tin,
     24                                            TransformsOut* tout) {
     25     GrGLVertexBuilder* vb = pb->getVertexShaderBuilder();
     26     tout->push_back_n(tin.count());
     27     fInstalledTransforms.push_back_n(tin.count());
     28     for (int i = 0; i < tin.count(); i++) {
     29         const ProcCoords& coordTransforms = tin[i];
     30         fInstalledTransforms[i].push_back_n(coordTransforms.count());
     31         for (int t = 0; t < coordTransforms.count(); t++) {
     32             SkString strUniName("StageMatrix");
     33             strUniName.appendf("_%i_%i", i, t);
     34             GrSLType varyingType;
     35 
     36             GrCoordSet coordType = coordTransforms[t]->sourceCoords();
     37             uint32_t type = coordTransforms[t]->getMatrix().getType();
     38             if (kLocal_GrCoordSet == coordType) {
     39                 type |= localMatrix.getType();
     40             }
     41             varyingType = SkToBool(SkMatrix::kPerspective_Mask & type) ? kVec3f_GrSLType :
     42                                                                          kVec2f_GrSLType;
     43             GrSLPrecision precision = coordTransforms[t]->precision();
     44 
     45             const char* uniName;
     46             fInstalledTransforms[i][t].fHandle =
     47                     pb->addUniform(GrGLProgramBuilder::kVertex_Visibility,
     48                                    kMat33f_GrSLType, precision,
     49                                    strUniName.c_str(),
     50                                    &uniName).toShaderBuilderIndex();
     51 
     52             SkString strVaryingName("MatrixCoord");
     53             strVaryingName.appendf("_%i_%i", i, t);
     54 
     55             GrGLVertToFrag v(varyingType);
     56             pb->addVarying(strVaryingName.c_str(), &v, precision);
     57 
     58             SkASSERT(kVec2f_GrSLType == varyingType || kVec3f_GrSLType == varyingType);
     59             SkNEW_APPEND_TO_TARRAY(&(*tout)[i], GrGLProcessor::TransformedCoords,
     60                                    (SkString(v.fsIn()), varyingType));
     61 
     62             // varying = matrix * coords (logically)
     63             if (kDevice_GrCoordSet == coordType) {
     64                 if (kVec2f_GrSLType == varyingType) {
     65                     if (kVec2f_GrSLType == posVar.getType()) {
     66                         vb->codeAppendf("%s = (%s * vec3(%s, 1)).xy;",
     67                                         v.vsOut(), uniName, posVar.c_str());
     68                     } else {
     69                         // The brackets here are just to scope the temp variable
     70                         vb->codeAppendf("{ vec3 temp = %s * %s;", uniName, posVar.c_str());
     71                         vb->codeAppendf("%s = vec2(temp.x/temp.z, temp.y/temp.z); }", v.vsOut());
     72                     }
     73                 } else {
     74                     if (kVec2f_GrSLType == posVar.getType()) {
     75                         vb->codeAppendf("%s = %s * vec3(%s, 1);",
     76                                         v.vsOut(), uniName, posVar.c_str());
     77                     } else {
     78                         vb->codeAppendf("%s = %s * %s;", v.vsOut(), uniName, posVar.c_str());
     79                     }
     80                 }
     81             } else {
     82                 if (kVec2f_GrSLType == varyingType) {
     83                     vb->codeAppendf("%s = (%s * vec3(%s, 1)).xy;", v.vsOut(), uniName, localCoords);
     84                 } else {
     85                     vb->codeAppendf("%s = %s * vec3(%s, 1);", v.vsOut(), uniName, localCoords);
     86                 }
     87             }
     88         }
     89     }
     90 }
     91 
     92 void GrGLGeometryProcessor::setupPosition(GrGLGPBuilder* pb,
     93                                           GrGPArgs* gpArgs,
     94                                           const char* posName,
     95                                           const SkMatrix& mat) {
     96     GrGLVertexBuilder* vsBuilder = pb->getVertexShaderBuilder();
     97     if (mat.isIdentity()) {
     98         gpArgs->fPositionVar.set(kVec2f_GrSLType, "pos2");
     99 
    100         vsBuilder->codeAppendf("vec2 %s = %s;", gpArgs->fPositionVar.c_str(), posName);
    101     } else if (!mat.hasPerspective()) {
    102         this->addUniformViewMatrix(pb);
    103         gpArgs->fPositionVar.set(kVec2f_GrSLType, "pos2");
    104 
    105         vsBuilder->codeAppendf("vec2 %s = vec2(%s * vec3(%s, 1));",
    106                                gpArgs->fPositionVar.c_str(), this->uViewM(), posName);
    107     } else {
    108         this->addUniformViewMatrix(pb);
    109         gpArgs->fPositionVar.set(kVec3f_GrSLType, "pos3");
    110 
    111         vsBuilder->codeAppendf("vec3 %s = %s * vec3(%s, 1);",
    112                                gpArgs->fPositionVar.c_str(), this->uViewM(), posName);
    113     }
    114 }
    115