skia2/include/gpu/GrInvariantOutput.h

335 lines
11 KiB
C++

/*
* Copyright 2014 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef GrInvariantOutput_DEFINED
#define GrInvariantOutput_DEFINED
#include "GrColor.h"
struct GrInitInvariantOutput {
GrInitInvariantOutput()
: fValidFlags(0)
, fColor(0)
, fIsSingleComponent(false)
, fIsLCDCoverage(false) {}
void setKnownFourComponents(GrColor color) {
fColor = color;
fValidFlags = kRGBA_GrColorComponentFlags;
fIsSingleComponent = false;
}
void setUnknownFourComponents() {
fValidFlags = 0;
fIsSingleComponent = false;
}
void setUnknownOpaqueFourComponents() {
fColor = 0xff << GrColor_SHIFT_A;
fValidFlags = kA_GrColorComponentFlag;
fIsSingleComponent = false;
}
void setKnownSingleComponent(uint8_t alpha) {
fColor = GrColorPackRGBA(alpha, alpha, alpha, alpha);
fValidFlags = kRGBA_GrColorComponentFlags;
fIsSingleComponent = true;
}
void setUnknownSingleComponent() {
fValidFlags = 0;
fIsSingleComponent = true;
}
void setUsingLCDCoverage() { fIsLCDCoverage = true; }
uint32_t fValidFlags;
GrColor fColor;
bool fIsSingleComponent;
bool fIsLCDCoverage; // Temorary data member until texture pixel configs are updated
};
class GrInvariantOutput {
public:
GrInvariantOutput(GrColor color, GrColorComponentFlags flags, bool isSingleComponent)
: fColor(color)
, fValidFlags(flags)
, fIsSingleComponent(isSingleComponent)
, fNonMulStageFound(false)
, fWillUseInputColor(true)
, fIsLCDCoverage(false) {}
GrInvariantOutput(const GrInitInvariantOutput& io)
: fColor(io.fColor)
, fValidFlags(io.fValidFlags)
, fIsSingleComponent(io.fIsSingleComponent)
, fNonMulStageFound(false)
, fWillUseInputColor(false)
, fIsLCDCoverage(io.fIsLCDCoverage) {}
virtual ~GrInvariantOutput() {}
enum ReadInput {
kWill_ReadInput,
kWillNot_ReadInput,
};
void mulByUnknownOpaqueFourComponents() {
SkDEBUGCODE(this->validate());
if (this->isOpaque()) {
fValidFlags = kA_GrColorComponentFlag;
fIsSingleComponent = false;
} else {
// Since the current state is not opaque we no longer care if the color being
// multiplied is opaque.
this->mulByUnknownFourComponents();
}
SkDEBUGCODE(this->validate());
}
void mulByUnknownFourComponents() {
SkDEBUGCODE(this->validate());
if (this->hasZeroAlpha()) {
this->internalSetToTransparentBlack();
} else {
this->internalSetToUnknown();
}
SkDEBUGCODE(this->validate());
}
void mulByUnknownSingleComponent() {
SkDEBUGCODE(this->validate());
if (this->hasZeroAlpha()) {
this->internalSetToTransparentBlack();
} else {
// We don't need to change fIsSingleComponent in this case
fValidFlags = 0;
}
SkDEBUGCODE(this->validate());
}
void mulByKnownSingleComponent(uint8_t alpha) {
SkDEBUGCODE(this->validate());
if (this->hasZeroAlpha() || 0 == alpha) {
this->internalSetToTransparentBlack();
} else {
if (alpha != 255) {
// Multiply color by alpha
fColor = GrColorPackRGBA(SkMulDiv255Round(GrColorUnpackR(fColor), alpha),
SkMulDiv255Round(GrColorUnpackG(fColor), alpha),
SkMulDiv255Round(GrColorUnpackB(fColor), alpha),
SkMulDiv255Round(GrColorUnpackA(fColor), alpha));
// We don't need to change fIsSingleComponent in this case
}
}
SkDEBUGCODE(this->validate());
}
void mulByKnownFourComponents(GrColor color) {
SkDEBUGCODE(this->validate());
uint32_t a;
if (GetAlphaAndCheckSingleChannel(color, &a)) {
this->mulByKnownSingleComponent(a);
} else {
if (color != 0xffffffff) {
fColor = GrColorPackRGBA(
SkMulDiv255Round(GrColorUnpackR(fColor), GrColorUnpackR(color)),
SkMulDiv255Round(GrColorUnpackG(fColor), GrColorUnpackG(color)),
SkMulDiv255Round(GrColorUnpackB(fColor), GrColorUnpackB(color)),
SkMulDiv255Round(GrColorUnpackA(fColor), a));
if (kRGBA_GrColorComponentFlags == fValidFlags) {
fIsSingleComponent = GetAlphaAndCheckSingleChannel(fColor, &a);
}
}
}
SkDEBUGCODE(this->validate());
}
// Ignores the incoming color's RGB and muls its alpha by color.
void mulAlphaByKnownFourComponents(GrColor color) {
SkDEBUGCODE(this->validate());
uint32_t a;
if (GetAlphaAndCheckSingleChannel(color, &a)) {
this->mulAlphaByKnownSingleComponent(a);
} else if (fValidFlags & kA_GrColorComponentFlag) {
GrColor preAlpha = GrColorUnpackA(fColor);
if (0 == preAlpha) {
this->internalSetToTransparentBlack();
} else {
// We know that color has different component values
fIsSingleComponent = false;
fColor = GrColorPackRGBA(
SkMulDiv255Round(preAlpha, GrColorUnpackR(color)),
SkMulDiv255Round(preAlpha, GrColorUnpackG(color)),
SkMulDiv255Round(preAlpha, GrColorUnpackB(color)),
SkMulDiv255Round(preAlpha, a));
fValidFlags = kRGBA_GrColorComponentFlags;
}
} else {
fIsSingleComponent = false;
fValidFlags = 0;
}
SkDEBUGCODE(this->validate());
}
// Ignores the incoming color's RGB and muls its alpha by the alpha param and sets all channels
// equal to that value.
void mulAlphaByKnownSingleComponent(uint8_t alpha) {
SkDEBUGCODE(this->validate());
if (0 == alpha || this->hasZeroAlpha()) {
this->internalSetToTransparentBlack();
} else {
if (fValidFlags & kA_GrColorComponentFlag) {
GrColor a = GrColorUnpackA(fColor);
a = SkMulDiv255Round(alpha, a);
fColor = GrColorPackRGBA(a, a, a, a);
fValidFlags = kRGBA_GrColorComponentFlags;
} else {
fValidFlags = 0;
}
fIsSingleComponent = true;
}
SkDEBUGCODE(this->validate());
}
void invalidateComponents(uint8_t invalidateFlags, ReadInput readsInput) {
SkDEBUGCODE(this->validate());
fValidFlags &= ~invalidateFlags;
fIsSingleComponent = false;
fNonMulStageFound = true;
if (kWillNot_ReadInput == readsInput) {
fWillUseInputColor = false;
}
SkDEBUGCODE(this->validate());
}
void setToOther(uint8_t validFlags, GrColor color, ReadInput readsInput) {
SkDEBUGCODE(this->validate());
fValidFlags = validFlags;
fColor = color;
fIsSingleComponent = false;
fNonMulStageFound = true;
if (kWillNot_ReadInput == readsInput) {
fWillUseInputColor = false;
}
if (kRGBA_GrColorComponentFlags == fValidFlags) {
uint32_t a;
if (GetAlphaAndCheckSingleChannel(color, &a)) {
fIsSingleComponent = true;
}
} else if (kA_GrColorComponentFlag & fValidFlags) {
// Assuming fColor is premul means if a is 0 the color must be all 0s.
if (!GrColorUnpackA(fColor)) {
this->internalSetToTransparentBlack();
}
}
SkDEBUGCODE(this->validate());
}
void setToUnknown(ReadInput readsInput) {
SkDEBUGCODE(this->validate());
this->internalSetToUnknown();
fNonMulStageFound= true;
if (kWillNot_ReadInput == readsInput) {
fWillUseInputColor = false;
}
SkDEBUGCODE(this->validate());
}
// Temporary setter to handle LCD text correctly until we improve texture pixel config queries
// and thus can rely solely on number of coverage components for RGA vs single channel coverage.
void setUsingLCDCoverage() {
fIsLCDCoverage = true;
}
GrColor color() const { return fColor; }
uint8_t validFlags() const { return fValidFlags; }
/**
* If isSingleComponent is true, then the flag values for r, g, b, and a must all be the
* same. If the flags are all set then all color components must be equal.
*/
SkDEBUGCODE(void validate() const;)
private:
friend class GrProcOptInfo;
/** Extracts the alpha channel and returns true if r,g,b == a. */
static bool GetAlphaAndCheckSingleChannel(GrColor color, uint32_t* alpha) {
*alpha = GrColorUnpackA(color);
return *alpha == GrColorUnpackR(color) && *alpha == GrColorUnpackG(color) &&
*alpha == GrColorUnpackB(color);
}
void reset(GrColor color, GrColorComponentFlags flags, bool isSingleComponent) {
fColor = color;
fValidFlags = flags;
fIsSingleComponent = isSingleComponent;
fNonMulStageFound = false;
fWillUseInputColor = true;
}
void reset(const GrInitInvariantOutput& io) {
fColor = io.fColor;
fValidFlags = io.fValidFlags;
fIsSingleComponent = io.fIsSingleComponent;
fNonMulStageFound = false;
fWillUseInputColor = true;
fIsLCDCoverage = io.fIsLCDCoverage;
}
void internalSetToTransparentBlack() {
fValidFlags = kRGBA_GrColorComponentFlags;
fColor = 0;
fIsSingleComponent = true;
}
void internalSetToUnknown() {
fValidFlags = 0;
fIsSingleComponent = false;
}
bool hasZeroAlpha() const {
return ((fValidFlags & kA_GrColorComponentFlag) && 0 == GrColorUnpackA(fColor));
}
bool isOpaque() const {
return ((fValidFlags & kA_GrColorComponentFlag) && 0xFF == GrColorUnpackA(fColor));
}
bool isSolidWhite() const {
return (fValidFlags == kRGBA_GrColorComponentFlags && 0xFFFFFFFF == fColor);
}
bool isSingleComponent() const { return fIsSingleComponent; }
bool willUseInputColor() const { return fWillUseInputColor; }
void resetWillUseInputColor() { fWillUseInputColor = true; }
bool allStagesMulInput() const { return !fNonMulStageFound; }
void resetNonMulStageFound() { fNonMulStageFound = false; }
bool isLCDCoverage() const { return fIsLCDCoverage; }
SkDEBUGCODE(bool colorComponentsAllEqual() const;)
/**
* If alpha is valid, check that any valid R,G,B values are <= A
*/
SkDEBUGCODE(bool validPreMulColor() const;)
GrColor fColor;
uint32_t fValidFlags;
bool fIsSingleComponent;
bool fNonMulStageFound;
bool fWillUseInputColor;
bool fIsLCDCoverage; // Temorary data member until texture pixel configs are updated
};
#endif