| /* |
| * Copyright 2014 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "effects/GrDisableColorXP.h" |
| #include "GrProcessor.h" |
| #include "gl/GrGLXferProcessor.h" |
| #include "gl/builders/GrGLFragmentShaderBuilder.h" |
| #include "gl/builders/GrGLProgramBuilder.h" |
| |
| /** |
| * This xfer processor disables color writing. Thus color and coverage and ignored and no blending |
| * occurs. This XP is usful for things like stenciling. |
| */ |
| class DisableColorXP : public GrXferProcessor { |
| public: |
| static GrXferProcessor* Create() { |
| return SkNEW(DisableColorXP); |
| } |
| |
| ~DisableColorXP() override {}; |
| |
| const char* name() const override { return "Disable Color"; } |
| |
| GrGLXferProcessor* createGLInstance() const override; |
| |
| private: |
| DisableColorXP(); |
| |
| GrXferProcessor::OptFlags onGetOptimizations(const GrProcOptInfo& colorPOI, |
| const GrProcOptInfo& coveragePOI, |
| bool doesStencilWrite, |
| GrColor* color, |
| const GrCaps& caps) override { |
| return GrXferProcessor::kIgnoreColor_OptFlag | GrXferProcessor::kIgnoreCoverage_OptFlag; |
| } |
| |
| void onGetGLProcessorKey(const GrGLSLCaps& caps, GrProcessorKeyBuilder* b) const override; |
| |
| void onGetBlendInfo(GrXferProcessor::BlendInfo* blendInfo) const override; |
| |
| bool onIsEqual(const GrXferProcessor& xpBase) const override { |
| return true; |
| } |
| |
| typedef GrXferProcessor INHERITED; |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| class GLDisableColorXP : public GrGLXferProcessor { |
| public: |
| GLDisableColorXP(const GrProcessor&) {} |
| |
| ~GLDisableColorXP() override {} |
| |
| static void GenKey(const GrProcessor&, const GrGLSLCaps&, GrProcessorKeyBuilder*) {} |
| |
| private: |
| void emitOutputsForBlendState(const EmitArgs& args) override { |
| // This emit code should be empty. However, on the nexus 6 there is a driver bug where if |
| // you do not give gl_FragColor a value, the gl context is lost and we end up drawing |
| // nothing. So this fix just sets the gl_FragColor arbitrarily to 0. |
| GrGLXPFragmentBuilder* fsBuilder = args.fPB->getFragmentShaderBuilder(); |
| fsBuilder->codeAppendf("%s = vec4(0);", args.fOutputPrimary); |
| } |
| |
| void onSetData(const GrGLProgramDataManager&, const GrXferProcessor&) override {} |
| |
| typedef GrGLXferProcessor INHERITED; |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| DisableColorXP::DisableColorXP() { |
| this->initClassID<DisableColorXP>(); |
| } |
| |
| void DisableColorXP::onGetGLProcessorKey(const GrGLSLCaps& caps, GrProcessorKeyBuilder* b) const { |
| GLDisableColorXP::GenKey(*this, caps, b); |
| } |
| |
| GrGLXferProcessor* DisableColorXP::createGLInstance() const { |
| return SkNEW_ARGS(GLDisableColorXP, (*this)); |
| } |
| |
| void DisableColorXP::onGetBlendInfo(GrXferProcessor::BlendInfo* blendInfo) const { |
| blendInfo->fWriteColor = false; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| GrDisableColorXPFactory::GrDisableColorXPFactory() { |
| this->initClassID<GrDisableColorXPFactory>(); |
| } |
| |
| GrXferProcessor* |
| GrDisableColorXPFactory::onCreateXferProcessor(const GrCaps& caps, |
| const GrProcOptInfo& colorPOI, |
| const GrProcOptInfo& covPOI, |
| bool hasMixedSamples, |
| const DstTexture* dst) const { |
| return DisableColorXP::Create(); |
| } |
| |
| GR_DEFINE_XP_FACTORY_TEST(GrDisableColorXPFactory); |
| |
| GrXPFactory* GrDisableColorXPFactory::TestCreate(GrProcessorTestData*) { |
| return GrDisableColorXPFactory::Create(); |
| } |
| |