blob: 38c8f91c277684fe87dffc462dae9d400b554997 [file] [log] [blame]
* 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 {
static GrXferProcessor* Create() {
return SkNEW(DisableColorXP);
~DisableColorXP() override {};
const char* name() const override { return "Disable Color"; }
GrGLXferProcessor* createGLInstance() const override;
bool hasSecondaryOutput() const override { return false; }
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 {
GLDisableColorXP(const GrProcessor&) {}
~GLDisableColorXP() override {}
static void GenKey(const GrProcessor&, const GrGLSLCaps&, GrProcessorKeyBuilder*) {}
void onEmitCode(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() {
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() {
GrDisableColorXPFactory::onCreateXferProcessor(const GrCaps& caps,
const GrProcOptInfo& colorPOI,
const GrProcOptInfo& covPOI,
const GrDeviceCoordTexture* dstCopy) const {
return DisableColorXP::Create();
GrXPFactory* GrDisableColorXPFactory::TestCreate(SkRandom* random,
const GrCaps&,
GrTexture*[]) {
return GrDisableColorXPFactory::Create();