/*
* 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 "GrRRectEffect.h"
#include "GrConvexPolyEffect.h"
#include "GrFragmentProcessor.h"
#include "GrInvariantOutput.h"
#include "GrOvalEffect.h"
#include "SkRRect.h"
#include "SkTLazy.h"
#include "glsl/GrGLSLFragmentProcessor.h"
#include "glsl/GrGLSLFragmentShaderBuilder.h"
#include "glsl/GrGLSLProgramDataManager.h"
#include "glsl/GrGLSLUniformHandler.h"
// The effects defined here only handle rrect radii >= kRadiusMin.
static const SkScalar kRadiusMin = SK_ScalarHalf;
//////////////////////////////////////////////////////////////////////////////
class CircularRRectEffect : public GrFragmentProcessor {
public:
enum CornerFlags {
kTopLeft_CornerFlag = (1 << SkRRect::kUpperLeft_Corner),
kTopRight_CornerFlag = (1 << SkRRect::kUpperRight_Corner),
kBottomRight_CornerFlag = (1 << SkRRect::kLowerRight_Corner),
kBottomLeft_CornerFlag = (1 << SkRRect::kLowerLeft_Corner),
kLeft_CornerFlags = kTopLeft_CornerFlag | kBottomLeft_CornerFlag,
kTop_CornerFlags = kTopLeft_CornerFlag | kTopRight_CornerFlag,
kRight_CornerFlags = kTopRight_CornerFlag | kBottomRight_CornerFlag,
kBottom_CornerFlags = kBottomLeft_CornerFlag | kBottomRight_CornerFlag,
kAll_CornerFlags = kTopLeft_CornerFlag | kTopRight_CornerFlag |
kBottomLeft_CornerFlag | kBottomRight_CornerFlag,
kNone_CornerFlags = 0
};
// The flags are used to indicate which corners are circluar (unflagged corners are assumed to
// be square).
static GrFragmentProcessor* Create(GrPrimitiveEdgeType, uint32_t circularCornerFlags,
const SkRRect&);
virtual ~CircularRRectEffect() {};
const char* name() const override { return "CircularRRect"; }
const SkRRect& getRRect() const { return fRRect; }
uint32_t getCircularCornerFlags() const { return fCircularCornerFlags; }
GrPrimitiveEdgeType getEdgeType() const { return fEdgeType; }
private:
CircularRRectEffect(GrPrimitiveEdgeType, uint32_t circularCornerFlags, const SkRRect&);
GrGLSLFragmentProcessor* onCreateGLSLInstance() const override;
void onGetGLSLProcessorKey(const GrGLSLCaps&, GrProcessorKeyBuilder*) const override;
bool onIsEqual(const GrFragmentProcessor& other) const override;
void onComputeInvariantOutput(GrInvariantOutput* inout) const override;
SkRRect fRRect;
GrPrimitiveEdgeType fEdgeType;
uint32_t fCircularCornerFlags;
GR_DECLARE_FRAGMENT_PROCESSOR_TEST;
typedef GrFragmentProcessor INHERITED;
};
GrFragmentProcessor* CircularRRectEffect::Create(GrPrimitiveEdgeType edgeType,
uint32_t circularCornerFlags,
const SkRRect& rrect) {
if (kFillAA_GrProcessorEdgeType != edgeType && kInverseFillAA_GrProcessorEdgeType != edgeType) {
return nullptr;
}
return new CircularRRectEffect(edgeType, circularCornerFlags, rrect);
}
void CircularRRectEffect::onComputeInvariantOutput(GrInvariantOutput* inout) const {
inout->mulByUnknownSingleComponent();
}
CircularRRectEffect::CircularRRectEffect(GrPrimitiveEdgeType edgeType, uint32_t circularCornerFlags,
const SkRRect& rrect)
: fRRect(rrect)
, fEdgeType(edgeType)
, fCircularCornerFlags(circularCornerFlags) {
this->initClassID<CircularRRectEffect>();
this->setWillReadFragmentPosition();
}
bool CircularRRectEffect::onIsEqual(const GrFragmentProcessor& other) const {
const CircularRRectEffect& crre = other.cast<CircularRRectEffect>();
// The corner flags are derived from fRRect, so no need to check them.
return fEdgeType == crre.fEdgeType && fRRect == crre.fRRect;
}
//////////////////////////////////////////////////////////////////////////////
GR_DEFINE_FRAGMENT_PROCESSOR_TEST(CircularRRectEffect);
const GrFragmentProcessor* CircularRRectEffect::TestCreate(GrProcessorTestData* d) {
SkScalar w = d->fRandom->nextRangeScalar(20.f, 1000.f);
SkScalar h = d->fRandom->nextRangeScalar(20.f, 1000.f);
SkScalar r = d->fRandom->nextRangeF(kRadiusMin, 9.f);
SkRRect rrect;
rrect.setRectXY(SkRect::MakeWH(w, h), r, r);
GrFragmentProcessor* fp;
do {
GrPrimitiveEdgeType et =
(GrPrimitiveEdgeType)d->fRandom->nextULessThan(kGrProcessorEdgeTypeCnt);
fp = GrRRectEffect::Create(et, rrect);
} while (nullptr == fp);
return fp;
}
//////////////////////////////////////////////////////////////////////////////
class GLCircularRRectEffect : public GrGLSLFragmentProcessor {
public:
GLCircularRRectEffect() {
fPrevRRect.setEmpty();
}
virtual void emitCode(EmitArgs&) override;
static inline void GenKey(const GrProcessor&, const GrGLSLCaps&, GrProcessorKeyBuilder*);
protected:
void onSetData(const GrGLSLProgramDataManager&, const GrProcessor&) override;
private:
GrGLSLProgramDataManager::UniformHandle fInnerRectUniform;
GrGLSLProgramDataManager::UniformHandle fRadiusPlusHalfUniform;
SkRRect fPrevRRect;
typedef GrGLSLFragmentProcessor INHERITED;
};
void GLCircularRRectEffect::emitCode(EmitArgs& args) {
const CircularRRectEffect& crre = args.fFp.cast<CircularRRectEffect>();
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
const char *rectName;
const char *radiusPlusHalfName;
// The inner rect is the rrect bounds inset by the radius. Its left, top, right, and bottom
// edges correspond to components x, y, z, and w, respectively. When a side of the rrect has
// only rectangular corners, that side's value corresponds to the rect edge's value outset by
// half a pixel.
fInnerRectUniform = uniformHandler->addUniform(kFragment_GrShaderFlag,
kVec4f_GrSLType, kDefault_GrSLPrecision,
"innerRect",
&rectName);
// x is (r + .5) and y is 1/(r + .5)
fRadiusPlusHalfUniform = uniformHandler->addUniform(kFragment_GrShaderFlag,
kVec2f_GrSLType, kDefault_GrSLPrecision,
"radiusPlusHalf",
&radiusPlusHalfName);
// If we're on a device with a "real" mediump then the length calculation could overflow.
SkString clampedCircleDistance;
if (args.fGLSLCaps->floatPrecisionVaries()) {
clampedCircleDistance.printf("clamp(%s.x * (1.0 - length(dxy * %s.y)), 0.0, 1.0);",
radiusPlusHalfName, radiusPlusHalfName);
} else {
clampedCircleDistance.printf("clamp(%s.x - length(dxy), 0.0, 1.0);", radiusPlusHalfName);
}
GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
const char* fragmentPos = fragBuilder->fragmentPosition();
// At each quarter-circle corner we compute a vector that is the offset of the fragment position
// from the circle center. The vector is pinned in x and y to be in the quarter-plane relevant
// to that corner. This means that points near the interior near the rrect top edge will have
// a vector that points straight up for both the TL left and TR corners. Computing an
// alpha from this vector at either the TR or TL corner will give the correct result. Similarly,
// fragments near the other three edges will get the correct AA. Fragments in the interior of
// the rrect will have a (0,0) vector at all four corners. So long as the radius > 0.5 they will
// correctly produce an alpha value of 1 at all four corners. We take the min of all the alphas.
// The code below is a simplified version of the above that performs maxs on the vector
// components before computing distances and alpha values so that only one distance computation
// need be computed to determine the min alpha.
//
// For the cases where one half of the rrect is rectangular we drop one of the x or y
// computations, compute a separate rect edge alpha for the rect side, and mul the two computed
// alphas together.
switch (crre.getCircularCornerFlags()) {
case CircularRRectEffect::kAll_CornerFlags:
fragBuilder->codeAppendf("vec2 dxy0 = %s.xy - %s.xy;", rectName, fragmentPos);
fragBuilder->codeAppendf("vec2 dxy1 = %s.xy - %s.zw;", fragmentPos, rectName);
fragBuilder->codeAppend("vec2 dxy = max(max(dxy0, dxy1), 0.0);");
fragBuilder->codeAppendf("float alpha = %s;", clampedCircleDistance.c_str());
break;
case CircularRRectEffect::kTopLeft_CornerFlag:
fragBuilder->codeAppendf("vec2 dxy = max(%s.xy - %s.xy, 0.0);",
rectName, fragmentPos);
fragBuilder->codeAppendf("float rightAlpha = clamp(%s.z - %s.x, 0.0, 1.0);",
rectName, fragmentPos);
fragBuilder->codeAppendf("float bottomAlpha = clamp(%s.w - %s.y, 0.0, 1.0);",
rectName, fragmentPos);
fragBuilder->codeAppendf("float alpha = bottomAlpha * rightAlpha * %s;",
clampedCircleDistance.c_str());
break;
case CircularRRectEffect::kTopRight_CornerFlag:
fragBuilder->codeAppendf("vec2 dxy = max(vec2(%s.x - %s.z, %s.y - %s.y), 0.0);",
fragmentPos, rectName, rectName, fragmentPos);
fragBuilder->codeAppendf("float leftAlpha = clamp(%s.x - %s.x, 0.0, 1.0);",
fragmentPos, rectName);
fragBuilder->codeAppendf("float bottomAlpha = clamp(%s.w - %s.y, 0.0, 1.0);",
rectName, fragmentPos);
fragBuilder->codeAppendf("float alpha = bottomAlpha * leftAlpha * %s;",
clampedCircleDistance.c_str());
break;
case CircularRRectEffect::kBottomRight_CornerFlag:
fragBuilder->codeAppendf("vec2 dxy = max(%s.xy - %s.zw, 0.0);",
fragmentPos, rectName);
fragBuilder->codeAppendf("float leftAlpha = clamp(%s.x - %s.x, 0.0, 1.0);",
fragmentPos, rectName);
fragBuilder->codeAppendf("float topAlpha = clamp(%s.y - %s.y, 0.0, 1.0);",
fragmentPos, rectName);
fragBuilder->codeAppendf("float alpha = topAlpha * leftAlpha * %s;",
clampedCircleDistance.c_str());
break;
case CircularRRectEffect::kBottomLeft_CornerFlag:
fragBuilder->codeAppendf("vec2 dxy = max(vec2(%s.x - %s.x, %s.y - %s.w), 0.0);",
rectName, fragmentPos, fragmentPos, rectName);
fragBuilder->codeAppendf("float rightAlpha = clamp(%s.z - %s.x, 0.0, 1.0);",
rectName, fragmentPos);
fragBuilder->codeAppendf("float topAlpha = clamp(%s.y - %s.y, 0.0, 1.0);",
fragmentPos, rectName);
fragBuilder->codeAppendf("float alpha = topAlpha * rightAlpha * %s;",
clampedCircleDistance.c_str());
break;
case CircularRRectEffect::kLeft_CornerFlags:
fragBuilder->codeAppendf("vec2 dxy0 = %s.xy - %s.xy;", rectName, fragmentPos);
fragBuilder->codeAppendf("float dy1 = %s.y - %s.w;", fragmentPos, rectName);
fragBuilder->codeAppend("vec2 dxy = max(vec2(dxy0.x, max(dxy0.y, dy1)), 0.0);");
fragBuilder->codeAppendf("float rightAlpha = clamp(%s.z - %s.x, 0.0, 1.0);",
rectName, fragmentPos);
fragBuilder->codeAppendf("float alpha = rightAlpha * %s;",
clampedCircleDistance.c_str());
break;
case CircularRRectEffect::kTop_CornerFlags:
fragBuilder->codeAppendf("vec2 dxy0 = %s.xy - %s.xy;", rectName, fragmentPos);
fragBuilder->codeAppendf("float dx1 = %s.x - %s.z;", fragmentPos, rectName);
fragBuilder->codeAppend("vec2 dxy = max(vec2(max(dxy0.x, dx1), dxy0.y), 0.0);");
fragBuilder->codeAppendf("float bottomAlpha = clamp(%s.w - %s.y, 0.0, 1.0);",
rectName, fragmentPos);
fragBuilder->codeAppendf("float alpha = bottomAlpha * %s;",
clampedCircleDistance.c_str());
break;
case CircularRRectEffect::kRight_CornerFlags:
fragBuilder->codeAppendf("float dy0 = %s.y - %s.y;", rectName, fragmentPos);
fragBuilder->codeAppendf("vec2 dxy1 = %s.xy - %s.zw;", fragmentPos, rectName);
fragBuilder->codeAppend("vec2 dxy = max(vec2(dxy1.x, max(dy0, dxy1.y)), 0.0);");
fragBuilder->codeAppendf("float leftAlpha = clamp(%s.x - %s.x, 0.0, 1.0);",
fragmentPos, rectName);
fragBuilder->codeAppendf("float alpha = leftAlpha * %s;",
clampedCircleDistance.c_str());
break;
case CircularRRectEffect::kBottom_CornerFlags:
fragBuilder->codeAppendf("float dx0 = %s.x - %s.x;", rectName, fragmentPos);
fragBuilder->codeAppendf("vec2 dxy1 = %s.xy - %s.zw;", fragmentPos, rectName);
fragBuilder->codeAppend("vec2 dxy = max(vec2(max(dx0, dxy1.x), dxy1.y), 0.0);");
fragBuilder->codeAppendf("float topAlpha = clamp(%s.y - %s.y, 0.0, 1.0);",
fragmentPos, rectName);
fragBuilder->codeAppendf("float alpha = topAlpha * %s;",
clampedCircleDistance.c_str());
break;
}
if (kInverseFillAA_GrProcessorEdgeType == crre.getEdgeType()) {
fragBuilder->codeAppend("alpha = 1.0 - alpha;");
}
fragBuilder->codeAppendf("%s = %s;", args.fOutputColor,
(GrGLSLExpr4(args.fInputColor) * GrGLSLExpr1("alpha")).c_str());
}
void GLCircularRRectEffect::GenKey(const GrProcessor& processor, const GrGLSLCaps&,
GrProcessorKeyBuilder* b) {
const CircularRRectEffect& crre = processor.cast<CircularRRectEffect>();
GR_STATIC_ASSERT(kGrProcessorEdgeTypeCnt <= 8);
b->add32((crre.getCircularCornerFlags() << 3) | crre.getEdgeType());
}
void GLCircularRRectEffect::onSetData(const GrGLSLProgramDataManager& pdman,
const GrProcessor& processor) {
const CircularRRectEffect& crre = processor.cast<CircularRRectEffect>();
const SkRRect& rrect = crre.getRRect();
if (rrect != fPrevRRect) {
SkRect rect = rrect.getBounds();
SkScalar radius = 0;
switch (crre.getCircularCornerFlags()) {
case CircularRRectEffect::kAll_CornerFlags:
SkASSERT(rrect.isSimpleCircular());
radius = rrect.getSimpleRadii().fX;
SkASSERT(radius >= kRadiusMin);
rect.inset(radius, radius);
break;
case CircularRRectEffect::kTopLeft_CornerFlag:
radius = rrect.radii(SkRRect::kUpperLeft_Corner).fX;
rect.fLeft += radius;
rect.fTop += radius;
rect.fRight += 0.5f;
rect.fBottom += 0.5f;
break;
case CircularRRectEffect::kTopRight_CornerFlag:
radius = rrect.radii(SkRRect::kUpperRight_Corner).fX;
rect.fLeft -= 0.5f;
rect.fTop += radius;
rect.fRight -= radius;
rect.fBottom += 0.5f;
break;
case CircularRRectEffect::kBottomRight_CornerFlag:
radius = rrect.radii(SkRRect::kLowerRight_Corner).fX;
rect.fLeft -= 0.5f;
rect.fTop -= 0.5f;
rect.fRight -= radius;
rect.fBottom -= radius;
break;
case CircularRRectEffect::kBottomLeft_CornerFlag:
radius = rrect.radii(SkRRect::kLowerLeft_Corner).fX;
rect.fLeft += radius;
rect.fTop -= 0.5f;
rect.fRight += 0.5f;
rect.fBottom -= radius;
break;
case CircularRRectEffect::kLeft_CornerFlags:
radius = rrect.radii(SkRRect::kUpperLeft_Corner).fX;
rect.fLeft += radius;
rect.fTop += radius;
rect.fRight += 0.5f;
rect.fBottom -= radius;
break;
case CircularRRectEffect::kTop_CornerFlags:
radius = rrect.radii(SkRRect::kUpperLeft_Corner).fX;
rect.fLeft += radius;
rect.fTop += radius;
rect.fRight -= radius;
rect.fBottom += 0.5f;
break;
case CircularRRectEffect::kRight_CornerFlags:
radius = rrect.radii(SkRRect::kUpperRight_Corner).fX;
rect.fLeft -= 0.5f;
rect.fTop += radius;
rect.fRight -= radius;
rect.fBottom -= radius;
break;
case CircularRRectEffect::kBottom_CornerFlags:
radius = rrect.radii(SkRRect::kLowerLeft_Corner).fX;
rect.fLeft += radius;
rect.fTop -= 0.5f;
rect.fRight -= radius;
rect.fBottom -= radius;
break;
default:
SkFAIL("Should have been one of the above cases.");
}
pdman.set4f(fInnerRectUniform, rect.fLeft, rect.fTop, rect.fRight, rect.fBottom);
radius += 0.5f;
pdman.set2f(fRadiusPlusHalfUniform, radius, 1.f / radius);
fPrevRRect = rrect;
}
}
////////////////////////////////////////////////////////////////////////////////////////////////////
void CircularRRectEffect::onGetGLSLProcessorKey(const GrGLSLCaps& caps,
GrProcessorKeyBuilder* b) const {
GLCircularRRectEffect::GenKey(*this, caps, b);
}
GrGLSLFragmentProcessor* CircularRRectEffect::onCreateGLSLInstance() const {
return new GLCircularRRectEffect;
}
//////////////////////////////////////////////////////////////////////////////
class EllipticalRRectEffect : public GrFragmentProcessor {
public:
static GrFragmentProcessor* Create(GrPrimitiveEdgeType, const SkRRect&);
virtual ~EllipticalRRectEffect() {};
const char* name() const override { return "EllipticalRRect"; }
const SkRRect& getRRect() const { return fRRect; }
GrPrimitiveEdgeType getEdgeType() const { return fEdgeType; }
private:
EllipticalRRectEffect(GrPrimitiveEdgeType, const SkRRect&);
GrGLSLFragmentProcessor* onCreateGLSLInstance() const override;
void onGetGLSLProcessorKey(const GrGLSLCaps&, GrProcessorKeyBuilder*) const override;
bool onIsEqual(const GrFragmentProcessor& other) const override;
void onComputeInvariantOutput(GrInvariantOutput* inout) const override;
SkRRect fRRect;
GrPrimitiveEdgeType fEdgeType;
GR_DECLARE_FRAGMENT_PROCESSOR_TEST;
typedef GrFragmentProcessor INHERITED;
};
GrFragmentProcessor*
EllipticalRRectEffect::Create(GrPrimitiveEdgeType edgeType, const SkRRect& rrect) {
if (kFillAA_GrProcessorEdgeType != edgeType && kInverseFillAA_GrProcessorEdgeType != edgeType) {
return nullptr;
}
return new EllipticalRRectEffect(edgeType, rrect);
}
void EllipticalRRectEffect::onComputeInvariantOutput(GrInvariantOutput* inout) const {
inout->mulByUnknownSingleComponent();
}
EllipticalRRectEffect::EllipticalRRectEffect(GrPrimitiveEdgeType edgeType, const SkRRect& rrect)
: fRRect(rrect)
, fEdgeType(edgeType) {
this->initClassID<EllipticalRRectEffect>();
this->setWillReadFragmentPosition();
}
bool EllipticalRRectEffect::onIsEqual(const GrFragmentProcessor& other) const {
const EllipticalRRectEffect& erre = other.cast<EllipticalRRectEffect>();
return fEdgeType == erre.fEdgeType && fRRect == erre.fRRect;
}
//////////////////////////////////////////////////////////////////////////////
GR_DEFINE_FRAGMENT_PROCESSOR_TEST(EllipticalRRectEffect);
const GrFragmentProcessor* EllipticalRRectEffect::TestCreate(GrProcessorTestData* d) {
SkScalar w = d->fRandom->nextRangeScalar(20.f, 1000.f);
SkScalar h = d->fRandom->nextRangeScalar(20.f, 1000.f);
SkVector r[4];
r[SkRRect::kUpperLeft_Corner].fX = d->fRandom->nextRangeF(kRadiusMin, 9.f);
// ensure at least one corner really is elliptical
do {
r[SkRRect::kUpperLeft_Corner].fY = d->fRandom->nextRangeF(kRadiusMin, 9.f);
} while (r[SkRRect::kUpperLeft_Corner].fY == r[SkRRect::kUpperLeft_Corner].fX);
SkRRect rrect;
if (d->fRandom->nextBool()) {
// half the time create a four-radii rrect.
r[SkRRect::kLowerRight_Corner].fX = d->fRandom->nextRangeF(kRadiusMin, 9.f);
r[SkRRect::kLowerRight_Corner].fY = d->fRandom->nextRangeF(kRadiusMin, 9.f);
r[SkRRect::kUpperRight_Corner].fX = r[SkRRect::kLowerRight_Corner].fX;
r[SkRRect::kUpperRight_Corner].fY = r[SkRRect::kUpperLeft_Corner].fY;
r[SkRRect::kLowerLeft_Corner].fX = r[SkRRect::kUpperLeft_Corner].fX;
r[SkRRect::kLowerLeft_Corner].fY = r[SkRRect::kLowerRight_Corner].fY;
rrect.setRectRadii(SkRect::MakeWH(w, h), r);
} else {
rrect.setRectXY(SkRect::MakeWH(w, h), r[SkRRect::kUpperLeft_Corner].fX,
r[SkRRect::kUpperLeft_Corner].fY);
}
GrFragmentProcessor* fp;
do {
GrPrimitiveEdgeType et =
(GrPrimitiveEdgeType)d->fRandom->nextULessThan(kGrProcessorEdgeTypeCnt);
fp = GrRRectEffect::Create(et, rrect);
} while (nullptr == fp);
return fp;
}
//////////////////////////////////////////////////////////////////////////////
class GLEllipticalRRectEffect : public GrGLSLFragmentProcessor {
public:
GLEllipticalRRectEffect() {
fPrevRRect.setEmpty();
}
void emitCode(EmitArgs&) override;
static inline void GenKey(const GrProcessor&, const GrGLSLCaps&, GrProcessorKeyBuilder*);
protected:
void onSetData(const GrGLSLProgramDataManager&, const GrProcessor&) override;
private:
GrGLSLProgramDataManager::UniformHandle fInnerRectUniform;
GrGLSLProgramDataManager::UniformHandle fInvRadiiSqdUniform;
GrGLSLProgramDataManager::UniformHandle fScaleUniform;
SkRRect fPrevRRect;
typedef GrGLSLFragmentProcessor INHERITED;
};
void GLEllipticalRRectEffect::emitCode(EmitArgs& args) {
const EllipticalRRectEffect& erre = args.fFp.cast<EllipticalRRectEffect>();
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
const char *rectName;
// The inner rect is the rrect bounds inset by the x/y radii
fInnerRectUniform = uniformHandler->addUniform(kFragment_GrShaderFlag,
kVec4f_GrSLType, kDefault_GrSLPrecision,
"innerRect",
&rectName);
GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
const char* fragmentPos = fragBuilder->fragmentPosition();
// At each quarter-ellipse corner we compute a vector that is the offset of the fragment pos
// to the ellipse center. The vector is pinned in x and y to be in the quarter-plane relevant
// to that corner. This means that points near the interior near the rrect top edge will have
// a vector that points straight up for both the TL left and TR corners. Computing an
// alpha from this vector at either the TR or TL corner will give the correct result. Similarly,
// fragments near the other three edges will get the correct AA. Fragments in the interior of
// the rrect will have a (0,0) vector at all four corners. So long as the radii > 0.5 they will
// correctly produce an alpha value of 1 at all four corners. We take the min of all the alphas.
//
// The code below is a simplified version of the above that performs maxs on the vector
// components before computing distances and alpha values so that only one distance computation
// need be computed to determine the min alpha.
fragBuilder->codeAppendf("vec2 dxy0 = %s.xy - %s.xy;", rectName, fragmentPos);
fragBuilder->codeAppendf("vec2 dxy1 = %s.xy - %s.zw;", fragmentPos, rectName);
// If we're on a device with a "real" mediump then we'll do the distance computation in a space
// that is normalized by the largest radius. The scale uniform will be scale, 1/scale. The
// radii uniform values are already in this normalized space.
const char* scaleName = nullptr;
if (args.fGLSLCaps->floatPrecisionVaries()) {
fScaleUniform = uniformHandler->addUniform(kFragment_GrShaderFlag,
kVec2f_GrSLType, kDefault_GrSLPrecision,
"scale", &scaleName);
}
// The uniforms with the inv squared radii are highp to prevent underflow.
switch (erre.getRRect().getType()) {
case SkRRect::kSimple_Type: {
const char *invRadiiXYSqdName;
fInvRadiiSqdUniform = uniformHandler->addUniform(kFragment_GrShaderFlag,
kVec2f_GrSLType,
kDefault_GrSLPrecision,
"invRadiiXY",
&invRadiiXYSqdName);
fragBuilder->codeAppend("vec2 dxy = max(max(dxy0, dxy1), 0.0);");
if (scaleName) {
fragBuilder->codeAppendf("dxy *= %s.y;", scaleName);
}
// Z is the x/y offsets divided by squared radii.
fragBuilder->codeAppendf("vec2 Z = dxy * %s.xy;", invRadiiXYSqdName);
break;
}
case SkRRect::kNinePatch_Type: {
const char *invRadiiLTRBSqdName;
fInvRadiiSqdUniform = uniformHandler->addUniform(kFragment_GrShaderFlag,
kVec4f_GrSLType,
kDefault_GrSLPrecision,
"invRadiiLTRB",
&invRadiiLTRBSqdName);
if (scaleName) {
fragBuilder->codeAppendf("dxy0 *= %s.y;", scaleName);
fragBuilder->codeAppendf("dxy1 *= %s.y;", scaleName);
}
fragBuilder->codeAppend("vec2 dxy = max(max(dxy0, dxy1), 0.0);");
// Z is the x/y offsets divided by squared radii. We only care about the (at most) one
// corner where both the x and y offsets are positive, hence the maxes. (The inverse
// squared radii will always be positive.)
fragBuilder->codeAppendf("vec2 Z = max(max(dxy0 * %s.xy, dxy1 * %s.zw), 0.0);",
invRadiiLTRBSqdName, invRadiiLTRBSqdName);
break;
}
default:
SkFAIL("RRect should always be simple or nine-patch.");
}
// implicit is the evaluation of (x/a)^2 + (y/b)^2 - 1.
fragBuilder->codeAppend("float implicit = dot(Z, dxy) - 1.0;");
// grad_dot is the squared length of the gradient of the implicit.
fragBuilder->codeAppend("float grad_dot = 4.0 * dot(Z, Z);");
// avoid calling inversesqrt on zero.
fragBuilder->codeAppend("grad_dot = max(grad_dot, 1.0e-4);");
fragBuilder->codeAppend("float approx_dist = implicit * inversesqrt(grad_dot);");
if (scaleName) {
fragBuilder->codeAppendf("approx_dist *= %s.x;", scaleName);
}
if (kFillAA_GrProcessorEdgeType == erre.getEdgeType()) {
fragBuilder->codeAppend("float alpha = clamp(0.5 - approx_dist, 0.0, 1.0);");
} else {
fragBuilder->codeAppend("float alpha = clamp(0.5 + approx_dist, 0.0, 1.0);");
}
fragBuilder->codeAppendf("%s = %s;", args.fOutputColor,
(GrGLSLExpr4(args.fInputColor) * GrGLSLExpr1("alpha")).c_str());
}
void GLEllipticalRRectEffect::GenKey(const GrProcessor& effect, const GrGLSLCaps&,
GrProcessorKeyBuilder* b) {
const EllipticalRRectEffect& erre = effect.cast<EllipticalRRectEffect>();
GR_STATIC_ASSERT(kLast_GrProcessorEdgeType < (1 << 3));
b->add32(erre.getRRect().getType() | erre.getEdgeType() << 3);
}
void GLEllipticalRRectEffect::onSetData(const GrGLSLProgramDataManager& pdman,
const GrProcessor& effect) {
const EllipticalRRectEffect& erre = effect.cast<EllipticalRRectEffect>();
const SkRRect& rrect = erre.getRRect();
// If we're using a scale factor to work around precision issues, choose the largest radius
// as the scale factor. The inv radii need to be pre-adjusted by the scale factor.
if (rrect != fPrevRRect) {
SkRect rect = rrect.getBounds();
const SkVector& r0 = rrect.radii(SkRRect::kUpperLeft_Corner);
SkASSERT(r0.fX >= kRadiusMin);
SkASSERT(r0.fY >= kRadiusMin);
switch (erre.getRRect().getType()) {
case SkRRect::kSimple_Type:
rect.inset(r0.fX, r0.fY);
if (fScaleUniform.isValid()) {
if (r0.fX > r0.fY) {
pdman.set2f(fInvRadiiSqdUniform, 1.f, (r0.fX * r0.fX) / (r0.fY * r0.fY));
pdman.set2f(fScaleUniform, r0.fX, 1.f / r0.fX);
} else {
pdman.set2f(fInvRadiiSqdUniform, (r0.fY * r0.fY) / (r0.fX * r0.fX), 1.f);
pdman.set2f(fScaleUniform, r0.fY, 1.f / r0.fY);
}
} else {
pdman.set2f(fInvRadiiSqdUniform, 1.f / (r0.fX * r0.fX),
1.f / (r0.fY * r0.fY));
}
break;
case SkRRect::kNinePatch_Type: {
const SkVector& r1 = rrect.radii(SkRRect::kLowerRight_Corner);
SkASSERT(r1.fX >= kRadiusMin);
SkASSERT(r1.fY >= kRadiusMin);
rect.fLeft += r0.fX;
rect.fTop += r0.fY;
rect.fRight -= r1.fX;
rect.fBottom -= r1.fY;
if (fScaleUniform.isValid()) {
float scale = SkTMax(SkTMax(r0.fX, r0.fY), SkTMax(r1.fX, r1.fY));
float scaleSqd = scale * scale;
pdman.set4f(fInvRadiiSqdUniform, scaleSqd / (r0.fX * r0.fX),
scaleSqd / (r0.fY * r0.fY),
scaleSqd / (r1.fX * r1.fX),
scaleSqd / (r1.fY * r1.fY));
pdman.set2f(fScaleUniform, scale, 1.f / scale);
} else {
pdman.set4f(fInvRadiiSqdUniform, 1.f / (r0.fX * r0.fX),
1.f / (r0.fY * r0.fY),
1.f / (r1.fX * r1.fX),
1.f / (r1.fY * r1.fY));
}
break;
}
default:
SkFAIL("RRect should always be simple or nine-patch.");
}
pdman.set4f(fInnerRectUniform, rect.fLeft, rect.fTop, rect.fRight, rect.fBottom);
fPrevRRect = rrect;
}
}
////////////////////////////////////////////////////////////////////////////////////////////////////
void EllipticalRRectEffect::onGetGLSLProcessorKey(const GrGLSLCaps& caps,
GrProcessorKeyBuilder* b) const {
GLEllipticalRRectEffect::GenKey(*this, caps, b);
}
GrGLSLFragmentProcessor* EllipticalRRectEffect::onCreateGLSLInstance() const {
return new GLEllipticalRRectEffect;
}
//////////////////////////////////////////////////////////////////////////////
GrFragmentProcessor* GrRRectEffect::Create(GrPrimitiveEdgeType edgeType, const SkRRect& rrect) {
if (rrect.isRect()) {
return GrConvexPolyEffect::Create(edgeType, rrect.getBounds());
}
if (rrect.isOval()) {
return GrOvalEffect::Create(edgeType, rrect.getBounds());
}
if (rrect.isSimple()) {
if (rrect.getSimpleRadii().fX < kRadiusMin || rrect.getSimpleRadii().fY < kRadiusMin) {
// In this case the corners are extremely close to rectangular and we collapse the
// clip to a rectangular clip.
return GrConvexPolyEffect::Create(edgeType, rrect.getBounds());
}
if (rrect.getSimpleRadii().fX == rrect.getSimpleRadii().fY) {
return CircularRRectEffect::Create(edgeType, CircularRRectEffect::kAll_CornerFlags,
rrect);
} else {
return EllipticalRRectEffect::Create(edgeType, rrect);
}
}
if (rrect.isComplex() || rrect.isNinePatch()) {
// Check for the "tab" cases - two adjacent circular corners and two square corners.
SkScalar circularRadius = 0;
uint32_t cornerFlags = 0;
SkVector radii[4];
bool squashedRadii = false;
for (int c = 0; c < 4; ++c) {
radii[c] = rrect.radii((SkRRect::Corner)c);
SkASSERT((0 == radii[c].fX) == (0 == radii[c].fY));
if (0 == radii[c].fX) {
// The corner is square, so no need to squash or flag as circular.
continue;
}
if (radii[c].fX < kRadiusMin || radii[c].fY < kRadiusMin) {
radii[c].set(0, 0);
squashedRadii = true;
continue;
}
if (radii[c].fX != radii[c].fY) {
cornerFlags = ~0U;
break;
}
if (!cornerFlags) {
circularRadius = radii[c].fX;
cornerFlags = 1 << c;
} else {
if (radii[c].fX != circularRadius) {
cornerFlags = ~0U;
break;
}
cornerFlags |= 1 << c;
}
}
switch (cornerFlags) {
case CircularRRectEffect::kAll_CornerFlags:
// This rrect should have been caught in the simple case above. Though, it would
// be correctly handled in the fallthrough code.
SkASSERT(false);
case CircularRRectEffect::kTopLeft_CornerFlag:
case CircularRRectEffect::kTopRight_CornerFlag:
case CircularRRectEffect::kBottomRight_CornerFlag:
case CircularRRectEffect::kBottomLeft_CornerFlag:
case CircularRRectEffect::kLeft_CornerFlags:
case CircularRRectEffect::kTop_CornerFlags:
case CircularRRectEffect::kRight_CornerFlags:
case CircularRRectEffect::kBottom_CornerFlags: {
SkTCopyOnFirstWrite<SkRRect> rr(rrect);
if (squashedRadii) {
rr.writable()->setRectRadii(rrect.getBounds(), radii);
}
return CircularRRectEffect::Create(edgeType, cornerFlags, *rr);
}
case CircularRRectEffect::kNone_CornerFlags:
return GrConvexPolyEffect::Create(edgeType, rrect.getBounds());
default: {
if (squashedRadii) {
// If we got here then we squashed some but not all the radii to zero. (If all
// had been squashed cornerFlags would be 0.) The elliptical effect doesn't
// support some rounded and some square corners.
return nullptr;
}
if (rrect.isNinePatch()) {
return EllipticalRRectEffect::Create(edgeType, rrect);
}
return nullptr;
}
}
}
return nullptr;
}