void GLCircleEffect::emitCode(EmitArgs& args) {
const CircleEffect& ce = args.fFp.cast<CircleEffect>();
const char *circleName;
// The circle uniform is (center.x, center.y, radius + 0.5, 1 / (radius + 0.5)) for regular
// fills and (..., radius - 0.5, 1 / (radius - 0.5)) for inverse fills.
fCircleUniform = args.fBuilder->addUniform(GrGLProgramBuilder::kFragment_Visibility,
kVec4f_GrSLType, kDefault_GrSLPrecision,
"circle",
&circleName);
GrGLFragmentBuilder* fsBuilder = args.fBuilder->getFragmentShaderBuilder();
const char* fragmentPos = fsBuilder->fragmentPosition();
SkASSERT(kHairlineAA_GrProcessorEdgeType != ce.getEdgeType());
// TODO: Right now the distance to circle caclulation is performed in a space normalized to the
// radius and then denormalized. This is to prevent overflow on devices that have a "real"
// mediump. It'd be nice to only to this on mediump devices but we currently don't have the
// caps here.
if (GrProcessorEdgeTypeIsInverseFill(ce.getEdgeType())) {
fsBuilder->codeAppendf("\t\tfloat d = (length((%s.xy - %s.xy) * %s.w) - 1.0) * %s.z;\n",
circleName, fragmentPos, circleName, circleName);
} else {
fsBuilder->codeAppendf("\t\tfloat d = (1.0 - length((%s.xy - %s.xy) * %s.w)) * %s.z;\n",
circleName, fragmentPos, circleName, circleName);
}
if (GrProcessorEdgeTypeIsAA(ce.getEdgeType())) {
fsBuilder->codeAppend("\t\td = clamp(d, 0.0, 1.0);\n");
} else {
fsBuilder->codeAppend("\t\td = d > 0.5 ? 1.0 : 0.0;\n");
}
fsBuilder->codeAppendf("\t\t%s = %s;\n", args.fOutputColor,
(GrGLSLExpr4(args.fInputColor) * GrGLSLExpr1("d")).c_str());
}
void GrGLConvexPolyEffect::emitCode(EmitArgs& args) {
const GrConvexPolyEffect& cpe = args.fFp.cast<GrConvexPolyEffect>();
const char *edgeArrayName;
fEdgeUniform = args.fUniformHandler->addUniformArray(GrGLSLUniformHandler::kFragment_Visibility,
kVec3f_GrSLType,
kDefault_GrSLPrecision,
"edges",
cpe.getEdgeCount(),
&edgeArrayName);
GrGLSLFragmentBuilder* fragBuilder = args.fFragBuilder;
fragBuilder->codeAppend("\t\tfloat alpha = 1.0;\n");
fragBuilder->codeAppend("\t\tfloat edge;\n");
const char* fragmentPos = fragBuilder->fragmentPosition();
for (int i = 0; i < cpe.getEdgeCount(); ++i) {
fragBuilder->codeAppendf("\t\tedge = dot(%s[%d], vec3(%s.x, %s.y, 1));\n",
edgeArrayName, i, fragmentPos, fragmentPos);
if (GrProcessorEdgeTypeIsAA(cpe.getEdgeType())) {
fragBuilder->codeAppend("\t\tedge = clamp(edge, 0.0, 1.0);\n");
} else {
fragBuilder->codeAppend("\t\tedge = edge >= 0.5 ? 1.0 : 0.0;\n");
}
fragBuilder->codeAppend("\t\talpha *= edge;\n");
}
if (GrProcessorEdgeTypeIsInverseFill(cpe.getEdgeType())) {
fragBuilder->codeAppend("\talpha = 1.0 - alpha;\n");
}
fragBuilder->codeAppendf("\t%s = %s;\n", args.fOutputColor,
(GrGLSLExpr4(args.fInputColor) * GrGLSLExpr1("alpha")).c_str());
}
void GLEllipseEffect::emitCode(EmitArgs& args) {
const EllipseEffect& ee = args.fFp.cast<EllipseEffect>();
const char *ellipseName;
// The ellipse uniform is (center.x, center.y, 1 / rx^2, 1 / ry^2)
// The last two terms can underflow on mediump, so we use highp.
fEllipseUniform = args.fBuilder->addUniform(GrGLProgramBuilder::kFragment_Visibility,
kVec4f_GrSLType, kHigh_GrSLPrecision,
"ellipse",
&ellipseName);
GrGLFragmentBuilder* fsBuilder = args.fBuilder->getFragmentShaderBuilder();
const char* fragmentPos = fsBuilder->fragmentPosition();
// d is the offset to the ellipse center
fsBuilder->codeAppendf("\t\tvec2 d = %s.xy - %s.xy;\n", fragmentPos, ellipseName);
fsBuilder->codeAppendf("\t\tvec2 Z = d * %s.zw;\n", ellipseName);
// implicit is the evaluation of (x/rx)^2 + (y/ry)^2 - 1.
fsBuilder->codeAppend("\t\tfloat implicit = dot(Z, d) - 1.0;\n");
// grad_dot is the squared length of the gradient of the implicit.
fsBuilder->codeAppendf("\t\tfloat grad_dot = 4.0 * dot(Z, Z);\n");
// avoid calling inversesqrt on zero.
fsBuilder->codeAppend("\t\tgrad_dot = max(grad_dot, 1.0e-4);\n");
fsBuilder->codeAppendf("\t\tfloat approx_dist = implicit * inversesqrt(grad_dot);\n");
switch (ee.getEdgeType()) {
case kFillAA_GrProcessorEdgeType:
fsBuilder->codeAppend("\t\tfloat alpha = clamp(0.5 - approx_dist, 0.0, 1.0);\n");
break;
case kInverseFillAA_GrProcessorEdgeType:
fsBuilder->codeAppend("\t\tfloat alpha = clamp(0.5 + approx_dist, 0.0, 1.0);\n");
break;
case kFillBW_GrProcessorEdgeType:
fsBuilder->codeAppend("\t\tfloat alpha = approx_dist > 0.0 ? 0.0 : 1.0;\n");
break;
case kInverseFillBW_GrProcessorEdgeType:
fsBuilder->codeAppend("\t\tfloat alpha = approx_dist > 0.0 ? 1.0 : 0.0;\n");
break;
case kHairlineAA_GrProcessorEdgeType:
SkFAIL("Hairline not expected here.");
}
fsBuilder->codeAppendf("\t\t%s = %s;\n", args.fOutputColor,
(GrGLSLExpr4(args.fInputColor) * GrGLSLExpr1("alpha")).c_str());
}
void GLAARectEffect::emitCode(GrGLFPBuilder* builder,
const GrFragmentProcessor& fp,
const char* outputColor,
const char* inputColor,
const TransformedCoordsArray&,
const TextureSamplerArray& samplers) {
const AARectEffect& aare = fp.cast<AARectEffect>();
const char *rectName;
// The rect uniform's xyzw refer to (left + 0.5, top + 0.5, right - 0.5, bottom - 0.5),
// respectively.
fRectUniform = builder->addUniform(GrGLProgramBuilder::kFragment_Visibility,
kVec4f_GrSLType,
kDefault_GrSLPrecision,
"rect",
&rectName);
GrGLFPFragmentBuilder* fsBuilder = builder->getFragmentShaderBuilder();
const char* fragmentPos = fsBuilder->fragmentPosition();
if (GrProcessorEdgeTypeIsAA(aare.getEdgeType())) {
// The amount of coverage removed in x and y by the edges is computed as a pair of negative
// numbers, xSub and ySub.
fsBuilder->codeAppend("\t\tfloat xSub, ySub;\n");
fsBuilder->codeAppendf("\t\txSub = min(%s.x - %s.x, 0.0);\n", fragmentPos, rectName);
fsBuilder->codeAppendf("\t\txSub += min(%s.z - %s.x, 0.0);\n", rectName, fragmentPos);
fsBuilder->codeAppendf("\t\tySub = min(%s.y - %s.y, 0.0);\n", fragmentPos, rectName);
fsBuilder->codeAppendf("\t\tySub += min(%s.w - %s.y, 0.0);\n", rectName, fragmentPos);
// Now compute coverage in x and y and multiply them to get the fraction of the pixel
// covered.
fsBuilder->codeAppendf("\t\tfloat alpha = (1.0 + max(xSub, -1.0)) * (1.0 + max(ySub, -1.0));\n");
} else {
fsBuilder->codeAppendf("\t\tfloat alpha = 1.0;\n");
fsBuilder->codeAppendf("\t\talpha *= (%s.x - %s.x) > -0.5 ? 1.0 : 0.0;\n", fragmentPos, rectName);
fsBuilder->codeAppendf("\t\talpha *= (%s.z - %s.x) > -0.5 ? 1.0 : 0.0;\n", rectName, fragmentPos);
fsBuilder->codeAppendf("\t\talpha *= (%s.y - %s.y) > -0.5 ? 1.0 : 0.0;\n", fragmentPos, rectName);
fsBuilder->codeAppendf("\t\talpha *= (%s.w - %s.y) > -0.5 ? 1.0 : 0.0;\n", rectName, fragmentPos);
}
if (GrProcessorEdgeTypeIsInverseFill(aare.getEdgeType())) {
fsBuilder->codeAppend("\t\talpha = 1.0 - alpha;\n");
}
fsBuilder->codeAppendf("\t\t%s = %s;\n", outputColor,
(GrGLSLExpr4(inputColor) * GrGLSLExpr1("alpha")).c_str());
}
void GrGLConvexPolyEffect::emitCode(GrGLFPBuilder* builder,
const GrFragmentProcessor& fp,
const char* outputColor,
const char* inputColor,
const TransformedCoordsArray&,
const TextureSamplerArray& samplers) {
const GrConvexPolyEffect& cpe = fp.cast<GrConvexPolyEffect>();
const char *edgeArrayName;
fEdgeUniform = builder->addUniformArray(GrGLProgramBuilder::kFragment_Visibility,
kVec3f_GrSLType,
kDefault_GrSLPrecision,
"edges",
cpe.getEdgeCount(),
&edgeArrayName);
GrGLFPFragmentBuilder* fsBuilder = builder->getFragmentShaderBuilder();
fsBuilder->codeAppend("\t\tfloat alpha = 1.0;\n");
fsBuilder->codeAppend("\t\tfloat edge;\n");
const char* fragmentPos = fsBuilder->fragmentPosition();
for (int i = 0; i < cpe.getEdgeCount(); ++i) {
fsBuilder->codeAppendf("\t\tedge = dot(%s[%d], vec3(%s.x, %s.y, 1));\n",
edgeArrayName, i, fragmentPos, fragmentPos);
if (GrProcessorEdgeTypeIsAA(cpe.getEdgeType())) {
fsBuilder->codeAppend("\t\tedge = clamp(edge, 0.0, 1.0);\n");
} else {
fsBuilder->codeAppend("\t\tedge = edge >= 0.5 ? 1.0 : 0.0;\n");
}
fsBuilder->codeAppend("\t\talpha *= edge;\n");
}
// Woe is me. See skbug.com/2149.
if (kTegra2_GrGLRenderer == builder->ctxInfo().renderer()) {
fsBuilder->codeAppend("\t\tif (-1.0 == alpha) {\n\t\t\tdiscard;\n\t\t}\n");
}
if (GrProcessorEdgeTypeIsInverseFill(cpe.getEdgeType())) {
fsBuilder->codeAppend("\talpha = 1.0 - alpha;\n");
}
fsBuilder->codeAppendf("\t%s = %s;\n", outputColor,
(GrGLSLExpr4(inputColor) * GrGLSLExpr1("alpha")).c_str());
}
void GLAARectEffect::emitCode(EmitArgs& args) {
const AARectEffect& aare = args.fFp.cast<AARectEffect>();
const char *rectName;
// The rect uniform's xyzw refer to (left + 0.5, top + 0.5, right - 0.5, bottom - 0.5),
// respectively.
fRectUniform = args.fUniformHandler->addUniform(GrGLSLUniformHandler::kFragment_Visibility,
kVec4f_GrSLType,
kDefault_GrSLPrecision,
"rect",
&rectName);
GrGLSLFragmentBuilder* fragBuilder = args.fFragBuilder;
const char* fragmentPos = fragBuilder->fragmentPosition();
if (GrProcessorEdgeTypeIsAA(aare.getEdgeType())) {
// The amount of coverage removed in x and y by the edges is computed as a pair of negative
// numbers, xSub and ySub.
fragBuilder->codeAppend("\t\tfloat xSub, ySub;\n");
fragBuilder->codeAppendf("\t\txSub = min(%s.x - %s.x, 0.0);\n", fragmentPos, rectName);
fragBuilder->codeAppendf("\t\txSub += min(%s.z - %s.x, 0.0);\n", rectName, fragmentPos);
fragBuilder->codeAppendf("\t\tySub = min(%s.y - %s.y, 0.0);\n", fragmentPos, rectName);
fragBuilder->codeAppendf("\t\tySub += min(%s.w - %s.y, 0.0);\n", rectName, fragmentPos);
// Now compute coverage in x and y and multiply them to get the fraction of the pixel
// covered.
fragBuilder->codeAppendf("\t\tfloat alpha = (1.0 + max(xSub, -1.0)) * (1.0 + max(ySub, -1.0));\n");
} else {
fragBuilder->codeAppendf("\t\tfloat alpha = 1.0;\n");
fragBuilder->codeAppendf("\t\talpha *= (%s.x - %s.x) > -0.5 ? 1.0 : 0.0;\n", fragmentPos, rectName);
fragBuilder->codeAppendf("\t\talpha *= (%s.z - %s.x) > -0.5 ? 1.0 : 0.0;\n", rectName, fragmentPos);
fragBuilder->codeAppendf("\t\talpha *= (%s.y - %s.y) > -0.5 ? 1.0 : 0.0;\n", fragmentPos, rectName);
fragBuilder->codeAppendf("\t\talpha *= (%s.w - %s.y) > -0.5 ? 1.0 : 0.0;\n", rectName, fragmentPos);
}
if (GrProcessorEdgeTypeIsInverseFill(aare.getEdgeType())) {
fragBuilder->codeAppend("\t\talpha = 1.0 - alpha;\n");
}
fragBuilder->codeAppendf("\t\t%s = %s;\n", args.fOutputColor,
(GrGLSLExpr4(args.fInputColor) * GrGLSLExpr1("alpha")).c_str());
}
bool GrGLShaderBuilder::genProgram(const GrEffectStage* colorStages[],
const GrEffectStage* coverageStages[]) {
const GrGLProgramDesc::KeyHeader& header = this->desc().getHeader();
///////////////////////////////////////////////////////////////////////////
// emit code to read the dst copy texture, if necessary
if (kNoDstRead_DstReadKey != header.fDstReadKey && !fGpu->glCaps().fbFetchSupport()) {
bool topDown = SkToBool(kTopLeftOrigin_DstReadKeyBit & header.fDstReadKey);
const char* dstCopyTopLeftName;
const char* dstCopyCoordScaleName;
const char* dstCopySamplerName;
uint32_t configMask;
if (SkToBool(kUseAlphaConfig_DstReadKeyBit & header.fDstReadKey)) {
configMask = kA_GrColorComponentFlag;
} else {
configMask = kRGBA_GrColorComponentFlags;
}
fUniformHandles.fDstCopySamplerUni =
this->addUniform(kFragment_Visibility, kSampler2D_GrSLType, "DstCopySampler",
&dstCopySamplerName);
fUniformHandles.fDstCopyTopLeftUni =
this->addUniform(kFragment_Visibility, kVec2f_GrSLType, "DstCopyUpperLeft",
&dstCopyTopLeftName);
fUniformHandles.fDstCopyScaleUni =
this->addUniform(kFragment_Visibility, kVec2f_GrSLType, "DstCopyCoordScale",
&dstCopyCoordScaleName);
const char* fragPos = this->fragmentPosition();
this->fsCodeAppend("\t// Read color from copy of the destination.\n");
this->fsCodeAppendf("\tvec2 _dstTexCoord = (%s.xy - %s) * %s;\n",
fragPos, dstCopyTopLeftName, dstCopyCoordScaleName);
if (!topDown) {
this->fsCodeAppend("\t_dstTexCoord.y = 1.0 - _dstTexCoord.y;\n");
}
this->fsCodeAppendf("\tvec4 %s = ", kDstCopyColorName);
append_texture_lookup(&fFSCode,
fGpu,
dstCopySamplerName,
"_dstTexCoord",
configMask,
"rgba");
this->fsCodeAppend(";\n\n");
}
///////////////////////////////////////////////////////////////////////////
// get the initial color and coverage to feed into the first effect in each effect chain
GrGLSLExpr4 inputColor;
GrGLSLExpr4 inputCoverage;
if (GrGLProgramDesc::kUniform_ColorInput == header.fColorInput) {
const char* name;
fUniformHandles.fColorUni =
this->addUniform(GrGLShaderBuilder::kFragment_Visibility, kVec4f_GrSLType, "Color",
&name);
inputColor = GrGLSLExpr4(name);
}
if (GrGLProgramDesc::kUniform_ColorInput == header.fCoverageInput) {
const char* name;
fUniformHandles.fCoverageUni =
this->addUniform(GrGLShaderBuilder::kFragment_Visibility, kVec4f_GrSLType, "Coverage",
&name);
inputCoverage = GrGLSLExpr4(name);
} else if (GrGLProgramDesc::kSolidWhite_ColorInput == header.fCoverageInput) {
inputCoverage = GrGLSLExpr4(1);
}
if (k110_GrGLSLGeneration != fGpu->glslGeneration()) {
fFSOutputs.push_back().set(kVec4f_GrSLType,
GrGLShaderVar::kOut_TypeModifier,
declared_color_output_name());
fHasCustomColorOutput = true;
}
this->emitCodeBeforeEffects(&inputColor, &inputCoverage);
///////////////////////////////////////////////////////////////////////////
// emit the per-effect code for both color and coverage effects
GrGLProgramDesc::EffectKeyProvider colorKeyProvider(
&this->desc(), GrGLProgramDesc::EffectKeyProvider::kColor_EffectType);
fColorEffects.reset(this->createAndEmitEffects(colorStages,
this->desc().numColorEffects(),
colorKeyProvider,
&inputColor));
GrGLProgramDesc::EffectKeyProvider coverageKeyProvider(
&this->desc(), GrGLProgramDesc::EffectKeyProvider::kCoverage_EffectType);
fCoverageEffects.reset(this->createAndEmitEffects(coverageStages,
this->desc().numCoverageEffects(),
coverageKeyProvider,
&inputCoverage));
this->emitCodeAfterEffects();
///////////////////////////////////////////////////////////////////////////
// write the secondary color output if necessary
if (GrGLProgramDesc::CoverageOutputUsesSecondaryOutput(header.fCoverageOutput)) {
const char* secondaryOutputName = this->enableSecondaryOutput();
// default coeff to ones for kCoverage_DualSrcOutput
GrGLSLExpr4 coeff(1);
if (GrGLProgramDesc::kSecondaryCoverageISA_CoverageOutput == header.fCoverageOutput) {
// Get (1-A) into coeff
coeff = GrGLSLExpr4::VectorCast(GrGLSLExpr1(1) - inputColor.a());
} else if (GrGLProgramDesc::kSecondaryCoverageISC_CoverageOutput ==
header.fCoverageOutput){
// Get (1-RGBA) into coeff
coeff = GrGLSLExpr4(1) - inputColor;
}
// Get coeff * coverage into modulate and then write that to the dual source output.
this->fsCodeAppendf("\t%s = %s;\n", secondaryOutputName, (coeff * inputCoverage).c_str());
}
///////////////////////////////////////////////////////////////////////////
// combine color and coverage as frag color
// Get "color * coverage" into fragColor
GrGLSLExpr4 fragColor = inputColor * inputCoverage;
// Now tack on "+(1-coverage)dst onto the frag color if we were asked to do so.
if (GrGLProgramDesc::kCombineWithDst_CoverageOutput == header.fCoverageOutput) {
GrGLSLExpr4 dstCoeff = GrGLSLExpr4(1) - inputCoverage;
GrGLSLExpr4 dstContribution = dstCoeff * GrGLSLExpr4(this->dstColor());
fragColor = fragColor + dstContribution;
}
this->fsCodeAppendf("\t%s = %s;\n", this->getColorOutputName(), fragColor.c_str());
if (!this->finish()) {
return false;
}
return true;
}
void GLEllipticalRRectEffect::emitCode(GrGLFPBuilder* builder,
const GrFragmentProcessor& effect,
const char* outputColor,
const char* inputColor,
const TransformedCoordsArray&,
const TextureSamplerArray& samplers) {
const EllipticalRRectEffect& erre = effect.cast<EllipticalRRectEffect>();
const char *rectName;
// The inner rect is the rrect bounds inset by the x/y radii
fInnerRectUniform = builder->addUniform(GrGLProgramBuilder::kFragment_Visibility,
kVec4f_GrSLType, kDefault_GrSLPrecision,
"innerRect",
&rectName);
GrGLFragmentBuilder* fsBuilder = builder->getFragmentShaderBuilder();
const char* fragmentPos = fsBuilder->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.
fsBuilder->codeAppendf("\t\tvec2 dxy0 = %s.xy - %s.xy;\n", rectName, fragmentPos);
fsBuilder->codeAppendf("\t\tvec2 dxy1 = %s.xy - %s.zw;\n", fragmentPos, rectName);
switch (erre.getRRect().getType()) {
case SkRRect::kSimple_Type: {
const char *invRadiiXYSqdName;
fInvRadiiSqdUniform = builder->addUniform(GrGLProgramBuilder::kFragment_Visibility,
kVec2f_GrSLType, kDefault_GrSLPrecision,
"invRadiiXY",
&invRadiiXYSqdName);
fsBuilder->codeAppend("\t\tvec2 dxy = max(max(dxy0, dxy1), 0.0);\n");
// Z is the x/y offsets divided by squared radii.
fsBuilder->codeAppendf("\t\tvec2 Z = dxy * %s;\n", invRadiiXYSqdName);
break;
}
case SkRRect::kNinePatch_Type: {
const char *invRadiiLTRBSqdName;
fInvRadiiSqdUniform = builder->addUniform(GrGLProgramBuilder::kFragment_Visibility,
kVec4f_GrSLType, kDefault_GrSLPrecision,
"invRadiiLTRB",
&invRadiiLTRBSqdName);
fsBuilder->codeAppend("\t\tvec2 dxy = max(max(dxy0, dxy1), 0.0);\n");
// 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.)
fsBuilder->codeAppendf("\t\tvec2 Z = max(max(dxy0 * %s.xy, dxy1 * %s.zw), 0.0);\n",
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.
fsBuilder->codeAppend("\t\tfloat implicit = dot(Z, dxy) - 1.0;\n");
// grad_dot is the squared length of the gradient of the implicit.
fsBuilder->codeAppendf("\t\tfloat grad_dot = 4.0 * dot(Z, Z);\n");
// avoid calling inversesqrt on zero.
fsBuilder->codeAppend("\t\tgrad_dot = max(grad_dot, 1.0e-4);\n");
fsBuilder->codeAppendf("\t\tfloat approx_dist = implicit * inversesqrt(grad_dot);\n");
if (kFillAA_GrProcessorEdgeType == erre.getEdgeType()) {
fsBuilder->codeAppend("\t\tfloat alpha = clamp(0.5 - approx_dist, 0.0, 1.0);\n");
} else {
fsBuilder->codeAppend("\t\tfloat alpha = clamp(0.5 + approx_dist, 0.0, 1.0);\n");
}
fsBuilder->codeAppendf("\t\t%s = %s;\n", outputColor,
(GrGLSLExpr4(inputColor) * GrGLSLExpr1("alpha")).c_str());
}
void GLCircularRRectEffect::emitCode(GrGLFPBuilder* builder,
const GrFragmentProcessor& fp,
const char* outputColor,
const char* inputColor,
const TransformedCoordsArray&,
const TextureSamplerArray& samplers) {
const CircularRRectEffect& crre = fp.cast<CircularRRectEffect>();
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 = builder->addUniform(GrGLProgramBuilder::kFragment_Visibility,
kVec4f_GrSLType, kDefault_GrSLPrecision,
"innerRect",
&rectName);
fRadiusPlusHalfUniform = builder->addUniform(GrGLProgramBuilder::kFragment_Visibility,
kFloat_GrSLType, kDefault_GrSLPrecision,
"radiusPlusHalf",
&radiusPlusHalfName);
GrGLFragmentBuilder* fsBuilder = builder->getFragmentShaderBuilder();
const char* fragmentPos = fsBuilder->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:
fsBuilder->codeAppendf("\t\tvec2 dxy0 = %s.xy - %s.xy;\n", rectName, fragmentPos);
fsBuilder->codeAppendf("\t\tvec2 dxy1 = %s.xy - %s.zw;\n", fragmentPos, rectName);
fsBuilder->codeAppend("\t\tvec2 dxy = max(max(dxy0, dxy1), 0.0);\n");
fsBuilder->codeAppendf("\t\tfloat alpha = clamp(%s - length(dxy), 0.0, 1.0);\n",
radiusPlusHalfName);
break;
case CircularRRectEffect::kTopLeft_CornerFlag:
fsBuilder->codeAppendf("\t\tvec2 dxy = max(%s.xy - %s.xy, 0.0);\n",
rectName, fragmentPos);
fsBuilder->codeAppendf("\t\tfloat rightAlpha = clamp(%s.z - %s.x, 0.0, 1.0);\n",
rectName, fragmentPos);
fsBuilder->codeAppendf("\t\tfloat bottomAlpha = clamp(%s.w - %s.y, 0.0, 1.0);\n",
rectName, fragmentPos);
fsBuilder->codeAppendf("\t\tfloat alpha = bottomAlpha * rightAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
radiusPlusHalfName);
break;
case CircularRRectEffect::kTopRight_CornerFlag:
fsBuilder->codeAppendf("\t\tvec2 dxy = max(vec2(%s.x - %s.z, %s.y - %s.y), 0.0);\n",
fragmentPos, rectName, rectName, fragmentPos);
fsBuilder->codeAppendf("\t\tfloat leftAlpha = clamp(%s.x - %s.x, 0.0, 1.0);\n",
fragmentPos, rectName);
fsBuilder->codeAppendf("\t\tfloat bottomAlpha = clamp(%s.w - %s.y, 0.0, 1.0);\n",
rectName, fragmentPos);
fsBuilder->codeAppendf("\t\tfloat alpha = bottomAlpha * leftAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
radiusPlusHalfName);
break;
case CircularRRectEffect::kBottomRight_CornerFlag:
fsBuilder->codeAppendf("\t\tvec2 dxy = max(%s.xy - %s.zw, 0.0);\n",
fragmentPos, rectName);
fsBuilder->codeAppendf("\t\tfloat leftAlpha = clamp(%s.x - %s.x, 0.0, 1.0);\n",
fragmentPos, rectName);
fsBuilder->codeAppendf("\t\tfloat topAlpha = clamp(%s.y - %s.y, 0.0, 1.0);\n",
fragmentPos, rectName);
fsBuilder->codeAppendf("\t\tfloat alpha = topAlpha * leftAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
radiusPlusHalfName);
break;
case CircularRRectEffect::kBottomLeft_CornerFlag:
fsBuilder->codeAppendf("\t\tvec2 dxy = max(vec2(%s.x - %s.x, %s.y - %s.w), 0.0);\n",
rectName, fragmentPos, fragmentPos, rectName);
fsBuilder->codeAppendf("\t\tfloat rightAlpha = clamp(%s.z - %s.x, 0.0, 1.0);\n",
rectName, fragmentPos);
fsBuilder->codeAppendf("\t\tfloat topAlpha = clamp(%s.y - %s.y, 0.0, 1.0);\n",
fragmentPos, rectName);
fsBuilder->codeAppendf("\t\tfloat alpha = topAlpha * rightAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
radiusPlusHalfName);
break;
case CircularRRectEffect::kLeft_CornerFlags:
fsBuilder->codeAppendf("\t\tvec2 dxy0 = %s.xy - %s.xy;\n", rectName, fragmentPos);
fsBuilder->codeAppendf("\t\tfloat dy1 = %s.y - %s.w;\n", fragmentPos, rectName);
fsBuilder->codeAppend("\t\tvec2 dxy = max(vec2(dxy0.x, max(dxy0.y, dy1)), 0.0);\n");
fsBuilder->codeAppendf("\t\tfloat rightAlpha = clamp(%s.z - %s.x, 0.0, 1.0);\n",
rectName, fragmentPos);
fsBuilder->codeAppendf("\t\tfloat alpha = rightAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
radiusPlusHalfName);
break;
case CircularRRectEffect::kTop_CornerFlags:
fsBuilder->codeAppendf("\t\tvec2 dxy0 = %s.xy - %s.xy;\n", rectName, fragmentPos);
fsBuilder->codeAppendf("\t\tfloat dx1 = %s.x - %s.z;\n", fragmentPos, rectName);
fsBuilder->codeAppend("\t\tvec2 dxy = max(vec2(max(dxy0.x, dx1), dxy0.y), 0.0);\n");
fsBuilder->codeAppendf("\t\tfloat bottomAlpha = clamp(%s.w - %s.y, 0.0, 1.0);\n",
rectName, fragmentPos);
fsBuilder->codeAppendf("\t\tfloat alpha = bottomAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
radiusPlusHalfName);
break;
case CircularRRectEffect::kRight_CornerFlags:
fsBuilder->codeAppendf("\t\tfloat dy0 = %s.y - %s.y;\n", rectName, fragmentPos);
fsBuilder->codeAppendf("\t\tvec2 dxy1 = %s.xy - %s.zw;\n", fragmentPos, rectName);
fsBuilder->codeAppend("\t\tvec2 dxy = max(vec2(dxy1.x, max(dy0, dxy1.y)), 0.0);\n");
fsBuilder->codeAppendf("\t\tfloat leftAlpha = clamp(%s.x - %s.x, 0.0, 1.0);\n",
fragmentPos, rectName);
fsBuilder->codeAppendf("\t\tfloat alpha = leftAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
radiusPlusHalfName);
break;
case CircularRRectEffect::kBottom_CornerFlags:
fsBuilder->codeAppendf("\t\tfloat dx0 = %s.x - %s.x;\n", rectName, fragmentPos);
fsBuilder->codeAppendf("\t\tvec2 dxy1 = %s.xy - %s.zw;\n", fragmentPos, rectName);
fsBuilder->codeAppend("\t\tvec2 dxy = max(vec2(max(dx0, dxy1.x), dxy1.y), 0.0);\n");
fsBuilder->codeAppendf("\t\tfloat topAlpha = clamp(%s.y - %s.y, 0.0, 1.0);\n",
fragmentPos, rectName);
fsBuilder->codeAppendf("\t\tfloat alpha = topAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
radiusPlusHalfName);
break;
}
if (kInverseFillAA_GrProcessorEdgeType == crre.getEdgeType()) {
fsBuilder->codeAppend("\t\talpha = 1.0 - alpha;\n");
}
fsBuilder->codeAppendf("\t\t%s = %s;\n", outputColor,
(GrGLSLExpr4(inputColor) * GrGLSLExpr1("alpha")).c_str());
}
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(GrGLSLUniformHandler::kFragment_Visibility,
kVec4f_GrSLType, kDefault_GrSLPrecision,
"innerRect",
&rectName);
GrGLSLFragmentBuilder* 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(GrGLSLUniformHandler::kFragment_Visibility,
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(
GrGLSLUniformHandler::kFragment_Visibility,
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(
GrGLSLUniformHandler::kFragment_Visibility,
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 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(GrGLSLUniformHandler::kFragment_Visibility,
kVec4f_GrSLType, kDefault_GrSLPrecision,
"innerRect",
&rectName);
// x is (r + .5) and y is 1/(r + .5)
fRadiusPlusHalfUniform = uniformHandler->addUniform(GrGLSLUniformHandler::kFragment_Visibility,
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);
}
GrGLSLFragmentBuilder* 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());
}
bool GrGLProgram::genProgram(GrGLShaderBuilder* builder,
const GrEffectStage* colorStages[],
const GrEffectStage* coverageStages[]) {
SkASSERT(0 == fProgramID);
const GrGLProgramDesc::KeyHeader& header = fDesc.getHeader();
// incoming color to current stage being processed.
GrGLSLExpr4 inColor = builder->getInputColor();
fColorEffects.reset(
builder->createAndEmitEffects(colorStages,
fDesc.effectKeys(),
fDesc.numColorEffects(),
&inColor));
///////////////////////////////////////////////////////////////////////////
// compute the partial coverage
GrGLSLExpr4 inCoverage = builder->getInputCoverage();
fCoverageEffects.reset(
builder->createAndEmitEffects(coverageStages,
fDesc.getEffectKeys() + fDesc.numColorEffects(),
fDesc.numCoverageEffects(),
&inCoverage));
if (GrGLProgramDesc::CoverageOutputUsesSecondaryOutput(header.fCoverageOutput)) {
const char* secondaryOutputName = builder->enableSecondaryOutput();
// default coeff to ones for kCoverage_DualSrcOutput
GrGLSLExpr4 coeff(1);
if (GrGLProgramDesc::kSecondaryCoverageISA_CoverageOutput == header.fCoverageOutput) {
// Get (1-A) into coeff
coeff = GrGLSLExpr4::VectorCast(GrGLSLExpr1(1) - inColor.a());
} else if (GrGLProgramDesc::kSecondaryCoverageISC_CoverageOutput == header.fCoverageOutput) {
// Get (1-RGBA) into coeff
coeff = GrGLSLExpr4(1) - inColor;
}
// Get coeff * coverage into modulate and then write that to the dual source output.
builder->fsCodeAppendf("\t%s = %s;\n", secondaryOutputName, (coeff * inCoverage).c_str());
}
///////////////////////////////////////////////////////////////////////////
// combine color and coverage as frag color
// Get "color * coverage" into fragColor
GrGLSLExpr4 fragColor = inColor * inCoverage;
// Now tack on "+(1-coverage)dst onto the frag color if we were asked to do so.
if (GrGLProgramDesc::kCombineWithDst_CoverageOutput == header.fCoverageOutput) {
GrGLSLExpr4 dstCoeff = GrGLSLExpr4(1) - inCoverage;
GrGLSLExpr4 dstContribution = dstCoeff * GrGLSLExpr4(builder->dstColor());
fragColor = fragColor + dstContribution;
}
builder->fsCodeAppendf("\t%s = %s;\n", builder->getColorOutputName(), fragColor.c_str());
if (!builder->finish(&fProgramID)) {
return false;
}
fUniformHandles.fRTHeightUni = builder->getRTHeightUniform();
fUniformHandles.fDstCopyTopLeftUni = builder->getDstCopyTopLeftUniform();
fUniformHandles.fDstCopyScaleUni = builder->getDstCopyScaleUniform();
fUniformHandles.fColorUni = builder->getColorUniform();
fUniformHandles.fCoverageUni = builder->getCoverageUniform();
fUniformHandles.fDstCopySamplerUni = builder->getDstCopySamplerUniform();
// This must be called after we set fDstCopySamplerUni above.
this->initSamplerUniforms();
return true;
}