src/third_party/skia/src/gpu/gl/builders/GrGLFragmentOnlyProgramBuilder.cpp

   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 "GrGLFragmentOnlyProgramBuilder.h"
   9 #include "../GrGpuGL.h"
  10
  11 GrGLFragmentOnlyProgramBuilder::GrGLFragmentOnlyProgramBuilder(GrGpuGL* gpu,
  12                                                                const GrGLProgramDesc& desc)
  13     : INHERITED(gpu, desc) {
  14     SkASSERT(desc.getHeader().fUseFragShaderOnly);
  15     SkASSERT(gpu->glCaps().pathRenderingSupport());
  16     SkASSERT(GrGLProgramDesc::kAttribute_ColorInput != desc.getHeader().fColorInput);
  17     SkASSERT(GrGLProgramDesc::kAttribute_ColorInput != desc.getHeader().fCoverageInput);
  18 }
  19
  20 int GrGLFragmentOnlyProgramBuilder::addTexCoordSets(int count) {
  21     int firstFreeCoordSet = fTexCoordSetCnt;
  22     fTexCoordSetCnt += count;
  23     SkASSERT(gpu()->glCaps().maxFixedFunctionTextureCoords() >= fTexCoordSetCnt);
  24     return firstFreeCoordSet;
  25 }
  26
  27 void
  28 GrGLFragmentOnlyProgramBuilder::createAndEmitEffects(const GrGeometryStage* geometryProcessor,
  29                                                      const GrFragmentStage* colorStages[],
  30                                                      const GrFragmentStage* coverageStages[],
  31                                                      GrGLSLExpr4* inputColor,
  32                                                      GrGLSLExpr4* inputCoverage) {
  33     ///////////////////////////////////////////////////////////////////////////
  34     // emit the per-effect code for both color and coverage effects
  35
  36     EffectKeyProvider colorKeyProvider(&this->desc(), EffectKeyProvider::kColor_EffectType);
  37     fColorEffects.reset(this->onCreateAndEmitEffects(colorStages,
  38                                                      this->desc().numColorEffects(),
  39                                                      colorKeyProvider,
  40                                                      inputColor));
  41
  42     EffectKeyProvider coverageKeyProvider(&this->desc(), EffectKeyProvider::kCoverage_EffectType);
  43     fCoverageEffects.reset(this->onCreateAndEmitEffects(coverageStages,
  44                                                         this->desc().numCoverageEffects(),
  45                                                         coverageKeyProvider,
  46                                                         inputCoverage));
  47 }
  48
  49 GrGLProgramEffects* GrGLFragmentOnlyProgramBuilder::onCreateAndEmitEffects(
  50         const GrFragmentStage* effectStages[], int effectCnt,
  51         const GrGLProgramDesc::EffectKeyProvider& keyProvider, GrGLSLExpr4* inOutFSColor) {
  52     fProgramEffects.reset(SkNEW_ARGS(GrGLPathTexGenProgramEffects, (effectCnt)));
  53     this->INHERITED::createAndEmitEffects(effectStages,
  54                                           effectCnt,
  55                                           keyProvider,
  56                                           inOutFSColor);
  57     return fProgramEffects.detach();
  58 }
  59
  60 void GrGLFragmentOnlyProgramBuilder::emitEffect(const GrProcessorStage& stage,
  61                                                 const GrProcessorKey& key,
  62                                                 const char* outColor,
  63                                                 const char* inColor,
  64                                                 int stageIndex) {
  65     SkASSERT(fProgramEffects.get());
  66     const GrProcessor& effect = *stage.getProcessor();
  67
  68     SkSTArray<2, GrGLProcessor::TransformedCoords> coords(effect.numTransforms());
  69     SkSTArray<4, GrGLProcessor::TextureSampler> samplers(effect.numTextures());
  70
  71     this->setupPathTexGen(stage, &coords);
  72     this->emitSamplers(effect, &samplers);
  73
  74     SkASSERT(fEffectEmitter);
  75     GrGLProcessor* glEffect = fEffectEmitter->createGLInstance();
  76     fProgramEffects->addEffect(glEffect);
  77
  78     GrGLFragmentShaderBuilder* fsBuilder = this->getFragmentShaderBuilder();
  79     // Enclose custom code in a block to avoid namespace conflicts
  80     SkString openBrace;
  81     openBrace.printf("\t{ // Stage %d: %s\n", stageIndex, glEffect->name());
  82     fsBuilder->codeAppend(openBrace.c_str());
  83
  84     fEffectEmitter->emit(key, outColor, inColor, coords, samplers);
  85
  86     fsBuilder->codeAppend("\t}\n");
  87 }
  88
  89 void GrGLFragmentOnlyProgramBuilder::setupPathTexGen(
  90         const GrProcessorStage& effectStage, GrGLProcessor::TransformedCoordsArray* outCoords) {
  91     int numTransforms = effectStage.getProcessor()->numTransforms();
  92     int texCoordIndex = this->addTexCoordSets(numTransforms);
  93
  94     fProgramEffects->addTransforms(texCoordIndex);
  95
  96     SkString name;
  97     for (int t = 0; t < numTransforms; ++t) {
  98         GrSLType type =
  99                 effectStage.isPerspectiveCoordTransform(t, false) ?
 100                         kVec3f_GrSLType :
 101                         kVec2f_GrSLType;
 102
 103         name.printf("%s(gl_TexCoord[%i])", GrGLSLTypeString(type), texCoordIndex++);
 104         SkNEW_APPEND_TO_TARRAY(outCoords, GrGLProcessor::TransformedCoords, (name, type));
 105     }
 106 }