blob: 9c247c901c9e7f898c269f5f73a41076f6affd4f [file] [log] [blame]
* Copyright 2011 Google Inc.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
#ifndef GrPaint_DEFINED
#define GrPaint_DEFINED
#include "include/core/SkBlendMode.h"
#include "include/core/SkRefCnt.h"
#include "include/core/SkRegion.h"
#include "src/core/SkTLazy.h"
#include "src/gpu/GrColor.h"
#include "src/gpu/GrFragmentProcessor.h"
class GrTextureProxy;
class GrXPFactory;
* The paint describes how color and coverage are computed at each pixel by GrContext draw
* functions and the how color is blended with the destination pixel.
* The paint allows installation of custom color and coverage stages. New types of stages are
* created by subclassing GrProcessor.
* The primitive color computation starts with the color specified by setColor(). This color is the
* input to the first color stage. Each color stage feeds its output to the next color stage.
* Fractional pixel coverage follows a similar flow. The GrGeometryProcessor (specified elsewhere)
* provides the initial coverage which is passed to the first coverage fragment processor, which
* feeds its output to next coverage fragment processor.
* setXPFactory is used to control blending between the output color and dest. It also implements
* the application of fractional coverage from the coverage pipeline.
class GrPaint {
GrPaint() = default;
~GrPaint() = default;
static GrPaint Clone(const GrPaint& src) { return GrPaint(src); }
* The initial color of the drawn primitive. Defaults to solid white.
void setColor4f(const SkPMColor4f& color) { fColor = color; }
const SkPMColor4f& getColor4f() const { return fColor; }
void setXPFactory(const GrXPFactory* xpFactory) {
fXPFactory = xpFactory;
fTrivial &= !SkToBool(xpFactory);
void setPorterDuffXPFactory(SkBlendMode mode);
void setCoverageSetOpXPFactory(SkRegion::Op, bool invertCoverage = false);
* Sets a processor for color computation.
void setColorFragmentProcessor(std::unique_ptr<GrFragmentProcessor> fp) {
SkASSERT(fColorFragmentProcessor == nullptr);
fColorFragmentProcessor = std::move(fp);
fTrivial = false;
* Appends an additional coverage processor to the coverage computation.
void setCoverageFragmentProcessor(std::unique_ptr<GrFragmentProcessor> fp) {
SkASSERT(fCoverageFragmentProcessor == nullptr);
fCoverageFragmentProcessor = std::move(fp);
fTrivial = false;
bool hasColorFragmentProcessor() const { return fColorFragmentProcessor ? true : false; }
int hasCoverageFragmentProcessor() const { return fCoverageFragmentProcessor ? true : false; }
int numTotalFragmentProcessors() const {
return (this->hasColorFragmentProcessor() ? 1 : 0) +
(this->hasCoverageFragmentProcessor() ? 1 : 0);
const GrXPFactory* getXPFactory() const { return fXPFactory; }
GrFragmentProcessor* getColorFragmentProcessor() const {
return fColorFragmentProcessor.get();
GrFragmentProcessor* getCoverageFragmentProcessor() const {
return fCoverageFragmentProcessor.get();
bool usesLocalCoords() const {
// The sample coords for the top level FPs are implicitly the GP's local coords.
return (fColorFragmentProcessor && fColorFragmentProcessor->usesSampleCoords()) ||
(fCoverageFragmentProcessor && fCoverageFragmentProcessor->usesSampleCoords());
* Returns true if the paint's output color will be constant after blending. If the result is
* true, constantColor will be updated to contain the constant color. Note that we can conflate
* coverage and color, so the actual values written to pixels with partial coverage may still
* not seem constant, even if this function returns true.
bool isConstantBlendedColor(SkPMColor4f* constantColor) const;
* A trivial paint is one that uses src-over and has no fragment processors.
* It may have variable sRGB settings.
bool isTrivial() const { return fTrivial; }
friend void assert_alive(GrPaint& p) {
// Since paint copying is expensive if there are fragment processors, we require going through
// the Clone() method.
GrPaint(const GrPaint&);
GrPaint& operator=(const GrPaint&) = delete;
friend class GrProcessorSet;
const GrXPFactory* fXPFactory = nullptr;
std::unique_ptr<GrFragmentProcessor> fColorFragmentProcessor;
std::unique_ptr<GrFragmentProcessor> fCoverageFragmentProcessor;
bool fTrivial = true;
SkPMColor4f fColor = SK_PMColor4fWHITE;
SkDEBUGCODE(bool fAlive = true;) // Set false after moved from.