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 GrGLCircleBlurFragmentProcessor::emitCode(EmitArgs& args) {
const char *dataName;
// The data is formatted as:
// x,y - the center of the circle
// z - the distance at which the intensity starts falling off (e.g., the start of the table)
// w - the size of the profile texture
fDataUniform = args.fBuilder->addUniform(GrGLSLProgramBuilder::kFragment_Visibility,
kVec4f_GrSLType,
kDefault_GrSLPrecision,
"data",
&dataName);
GrGLSLFragmentBuilder* fsBuilder = args.fBuilder->getFragmentShaderBuilder();
const char *fragmentPos = fsBuilder->fragmentPosition();
if (args.fInputColor) {
fsBuilder->codeAppendf("vec4 src=%s;", args.fInputColor);
} else {
fsBuilder->codeAppendf("vec4 src=vec4(1);");
}
fsBuilder->codeAppendf("vec2 vec = %s.xy - %s.xy;", fragmentPos, dataName);
fsBuilder->codeAppendf("float dist = (length(vec) - %s.z + 0.5) / %s.w;", dataName, dataName);
fsBuilder->codeAppendf("float intensity = ");
fsBuilder->appendTextureLookup(args.fSamplers[0], "vec2(dist, 0.5)");
fsBuilder->codeAppend(".a;");
fsBuilder->codeAppendf("%s = src * intensity;\n", args.fOutputColor );
}
void GLDitherEffect::emitCode(EmitArgs& args) {
GrGLSLFragmentBuilder* fragBuilder = args.fFragBuilder;
// Generate a random number based on the fragment position. For this
// random number generator, we use the "GLSL rand" function
// that seems to be floating around on the internet. It works under
// the assumption that sin(<big number>) oscillates with high frequency
// and sampling it will generate "randomness". Since we're using this
// for rendering and not cryptography it should be OK.
// For each channel c, add the random offset to the pixel to either bump
// it up or let it remain constant during quantization.
fragBuilder->codeAppendf("\t\tfloat r = "
"fract(sin(dot(%s.xy ,vec2(12.9898,78.233))) * 43758.5453);\n",
fragBuilder->fragmentPosition());
fragBuilder->codeAppendf("\t\t%s = (1.0/255.0) * vec4(r, r, r, r) + %s;\n",
args.fOutputColor, GrGLSLExpr4(args.fInputColor).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());
}
void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override {
const PLSQuadEdgeEffect& qe = args.fGP.cast<PLSQuadEdgeEffect>();
GrGLSLVertexBuilder* vsBuilder = args.fVertBuilder;
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
// emit attributes
varyingHandler->emitAttributes(qe);
GrGLSLVertToFrag uv(kVec2f_GrSLType);
varyingHandler->addVarying("uv", &uv, kHigh_GrSLPrecision);
vsBuilder->codeAppendf("%s = %s;", uv.vsOut(), qe.inUV()->fName);
GrGLSLVertToFrag ep1(kVec2f_GrSLType);
varyingHandler->addVarying("endpoint1", &ep1, kHigh_GrSLPrecision);
vsBuilder->codeAppendf("%s = vec2(%s.x, %s.y);", ep1.vsOut(),
qe.inEndpoint1()->fName, qe.inEndpoint1()->fName);
GrGLSLVertToFrag ep2(kVec2f_GrSLType);
varyingHandler->addVarying("endpoint2", &ep2, kHigh_GrSLPrecision);
vsBuilder->codeAppendf("%s = vec2(%s.x, %s.y);", ep2.vsOut(),
qe.inEndpoint2()->fName, qe.inEndpoint2()->fName);
GrGLSLVertToFrag delta(kVec2f_GrSLType);
varyingHandler->addVarying("delta", &delta, kHigh_GrSLPrecision);
vsBuilder->codeAppendf("%s = vec2(%s.x - %s.x, %s.y - %s.y) * 0.5;",
delta.vsOut(), ep1.vsOut(), ep2.vsOut(), ep2.vsOut(),
ep1.vsOut());
GrGLSLVertToFrag windings(kInt_GrSLType);
varyingHandler->addFlatVarying("windings", &windings, kLow_GrSLPrecision);
vsBuilder->codeAppendf("%s = %s;",
windings.vsOut(), qe.inWindings()->fName);
// Setup position
this->setupPosition(vsBuilder, gpArgs, qe.inPosition()->fName);
// emit transforms
this->emitTransforms(vsBuilder, varyingHandler, uniformHandler, gpArgs->fPositionVar,
qe.inPosition()->fName, qe.localMatrix(), args.fTransformsIn,
args.fTransformsOut);
GrGLSLFragmentBuilder* fsBuilder = args.fFragBuilder;
SkAssertResult(fsBuilder->enableFeature(
GrGLSLFragmentShaderBuilder::kPixelLocalStorage_GLSLFeature));
SkAssertResult(fsBuilder->enableFeature(
GrGLSLFragmentShaderBuilder::kStandardDerivatives_GLSLFeature));
static const int QUAD_ARGS = 2;
GrGLSLShaderVar inQuadArgs[QUAD_ARGS] = {
GrGLSLShaderVar("dot", kFloat_GrSLType, 0, kHigh_GrSLPrecision),
GrGLSLShaderVar("uv", kVec2f_GrSLType, 0, kHigh_GrSLPrecision)
};
SkString inQuadName;
const char* inQuadCode = "if (uv.x * uv.x <= uv.y) {"
"return dot >= 0.0;"
"} else {"
"return false;"
"}";
fsBuilder->emitFunction(kBool_GrSLType, "in_quad", QUAD_ARGS, inQuadArgs, inQuadCode,
&inQuadName);
fsBuilder->declAppendf(GR_GL_PLS_PATH_DATA_DECL);
// keep the derivative instructions outside the conditional
fsBuilder->codeAppendf("highp vec2 uvdX = dFdx(%s);", uv.fsIn());
fsBuilder->codeAppendf("highp vec2 uvdY = dFdy(%s);", uv.fsIn());
fsBuilder->codeAppend("highp vec2 uvIncX = uvdX * 0.45 + uvdY * -0.1;");
fsBuilder->codeAppend("highp vec2 uvIncY = uvdX * 0.1 + uvdY * 0.55;");
fsBuilder->codeAppendf("highp vec2 uv = %s.xy - uvdX * 0.35 - uvdY * 0.25;",
uv.fsIn());
fsBuilder->codeAppendf("highp vec2 firstSample = %s.xy - vec2(0.25);",
fsBuilder->fragmentPosition());
fsBuilder->codeAppendf("highp float d = dot(%s, (firstSample - %s).yx) * 2.0;",
delta.fsIn(), ep1.fsIn());
fsBuilder->codeAppendf("pls.windings[0] += %s(d, uv) ? %s : 0;", inQuadName.c_str(),
windings.fsIn());
fsBuilder->codeAppend("uv += uvIncX;");
fsBuilder->codeAppendf("d += %s.x;", delta.fsIn());
fsBuilder->codeAppendf("pls.windings[1] += %s(d, uv) ? %s : 0;", inQuadName.c_str(),
windings.fsIn());
fsBuilder->codeAppend("uv += uvIncY;");
fsBuilder->codeAppendf("d += %s.y;", delta.fsIn());
fsBuilder->codeAppendf("pls.windings[2] += %s(d, uv) ? %s : 0;", inQuadName.c_str(),
windings.fsIn());
fsBuilder->codeAppend("uv -= uvIncX;");
fsBuilder->codeAppendf("d -= %s.x;", delta.fsIn());
fsBuilder->codeAppendf("pls.windings[3] += %s(d, uv) ? %s : 0;", inQuadName.c_str(),
windings.fsIn());
}
void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override {
const PLSAATriangleEffect& te = args.fGP.cast<PLSAATriangleEffect>();
GrGLSLVertexBuilder* vsBuilder = args.fVertBuilder;
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
varyingHandler->emitAttributes(te);
this->setupPosition(vsBuilder, gpArgs, te.inPosition()->fName);
GrGLSLVertToFrag v1(kVec2f_GrSLType);
varyingHandler->addVarying("Vertex1", &v1, kHigh_GrSLPrecision);
vsBuilder->codeAppendf("%s = vec2(%s.x, %s.y);",
v1.vsOut(),
te.inVertex1()->fName,
te.inVertex1()->fName);
GrGLSLVertToFrag v2(kVec2f_GrSLType);
varyingHandler->addVarying("Vertex2", &v2, kHigh_GrSLPrecision);
vsBuilder->codeAppendf("%s = vec2(%s.x, %s.y);",
v2.vsOut(),
te.inVertex2()->fName,
te.inVertex2()->fName);
GrGLSLVertToFrag v3(kVec2f_GrSLType);
varyingHandler->addVarying("Vertex3", &v3, kHigh_GrSLPrecision);
vsBuilder->codeAppendf("%s = vec2(%s.x, %s.y);",
v3.vsOut(),
te.inVertex3()->fName,
te.inVertex3()->fName);
GrGLSLVertToFrag delta1(kVec2f_GrSLType);
varyingHandler->addVarying("delta1", &delta1, kHigh_GrSLPrecision);
vsBuilder->codeAppendf("%s = vec2(%s.x - %s.x, %s.y - %s.y) * 0.5;",
delta1.vsOut(), v1.vsOut(), v2.vsOut(), v2.vsOut(), v1.vsOut());
GrGLSLVertToFrag delta2(kVec2f_GrSLType);
varyingHandler->addVarying("delta2", &delta2, kHigh_GrSLPrecision);
vsBuilder->codeAppendf("%s = vec2(%s.x - %s.x, %s.y - %s.y) * 0.5;",
delta2.vsOut(), v2.vsOut(), v3.vsOut(), v3.vsOut(), v2.vsOut());
GrGLSLVertToFrag delta3(kVec2f_GrSLType);
varyingHandler->addVarying("delta3", &delta3, kHigh_GrSLPrecision);
vsBuilder->codeAppendf("%s = vec2(%s.x - %s.x, %s.y - %s.y) * 0.5;",
delta3.vsOut(), v3.vsOut(), v1.vsOut(), v1.vsOut(), v3.vsOut());
GrGLSLVertToFrag windings(kInt_GrSLType);
varyingHandler->addFlatVarying("windings", &windings, kLow_GrSLPrecision);
vsBuilder->codeAppendf("%s = %s;",
windings.vsOut(), te.inWindings()->fName);
// emit transforms
this->emitTransforms(vsBuilder, varyingHandler, uniformHandler, gpArgs->fPositionVar,
te.inPosition()->fName, te.localMatrix(), args.fTransformsIn,
args.fTransformsOut);
GrGLSLFragmentBuilder* fsBuilder = args.fFragBuilder;
SkAssertResult(fsBuilder->enableFeature(
GrGLSLFragmentShaderBuilder::kPixelLocalStorage_GLSLFeature));
SkAssertResult(fsBuilder->enableFeature(
GrGLSLFragmentShaderBuilder::kStandardDerivatives_GLSLFeature));
fsBuilder->declAppendf(GR_GL_PLS_PATH_DATA_DECL);
// Compute four subsamples, each shifted a quarter pixel along x and y from
// gl_FragCoord. The oriented box positioning of the subsamples is of course not
// optimal, but it greatly simplifies the math and this simplification is necessary for
// performance reasons.
fsBuilder->codeAppendf("highp vec2 firstSample = %s.xy - vec2(0.25);",
fsBuilder->fragmentPosition());
fsBuilder->codeAppendf("highp vec2 delta1 = %s;", delta1.fsIn());
fsBuilder->codeAppendf("highp vec2 delta2 = %s;", delta2.fsIn());
fsBuilder->codeAppendf("highp vec2 delta3 = %s;", delta3.fsIn());
// Check whether first sample is inside the triangle by computing three dot products. If
// all are < 0, we're inside. The first vector in each case is half of what it is
// "supposed" to be, because we re-use them later as adjustment factors for which half
// is the correct value, so we multiply the dots by two to compensate.
fsBuilder->codeAppendf("highp float d1 = dot(delta1, (firstSample - %s).yx) * 2.0;",
v1.fsIn());
fsBuilder->codeAppendf("highp float d2 = dot(delta2, (firstSample - %s).yx) * 2.0;",
v2.fsIn());
fsBuilder->codeAppendf("highp float d3 = dot(delta3, (firstSample - %s).yx) * 2.0;",
v3.fsIn());
fsBuilder->codeAppend("highp float dmax = max(d1, max(d2, d3));");
fsBuilder->codeAppendf("pls.windings[0] += (dmax <= 0.0) ? %s : 0;", windings.fsIn());
// for subsequent samples, we don't recalculate the entire dot product -- just adjust it
// to the value it would have if we did recompute it.
fsBuilder->codeAppend("d1 += delta1.x;");
fsBuilder->codeAppend("d2 += delta2.x;");
fsBuilder->codeAppend("d3 += delta3.x;");
fsBuilder->codeAppend("dmax = max(d1, max(d2, d3));");
fsBuilder->codeAppendf("pls.windings[1] += (dmax <= 0.0) ? %s : 0;", windings.fsIn());
fsBuilder->codeAppend("d1 += delta1.y;");
fsBuilder->codeAppend("d2 += delta2.y;");
fsBuilder->codeAppend("d3 += delta3.y;");
fsBuilder->codeAppend("dmax = max(d1, max(d2, d3));");
fsBuilder->codeAppendf("pls.windings[2] += (dmax <= 0.0) ? %s : 0;", windings.fsIn());
fsBuilder->codeAppend("d1 -= delta1.x;");
fsBuilder->codeAppend("d2 -= delta2.x;");
fsBuilder->codeAppend("d3 -= delta3.x;");
fsBuilder->codeAppend("dmax = max(d1, max(d2, d3));");
fsBuilder->codeAppendf("pls.windings[3] += (dmax <= 0.0) ? %s : 0;", windings.fsIn());
}
void GLEllipticalRRectEffect::emitCode(EmitArgs& args) {
const EllipticalRRectEffect& erre = args.fFp.cast<EllipticalRRectEffect>();
const char *rectName;
// The inner rect is the rrect bounds inset by the x/y radii
fInnerRectUniform = args.fBuilder->addUniform(GrGLSLProgramBuilder::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("\t\tvec2 dxy0 = %s.xy - %s.xy;\n", rectName, fragmentPos);
fragBuilder->codeAppendf("\t\tvec2 dxy1 = %s.xy - %s.zw;\n", fragmentPos, rectName);
// The uniforms with the inv squared radii are highp to prevent underflow.
switch (erre.getRRect().getType()) {
case SkRRect::kSimple_Type: {
const char *invRadiiXYSqdName;
fInvRadiiSqdUniform = args.fBuilder->addUniform(
GrGLSLProgramBuilder::kFragment_Visibility,
kVec2f_GrSLType, kHigh_GrSLPrecision,
"invRadiiXY",
&invRadiiXYSqdName);
fragBuilder->codeAppend("\t\tvec2 dxy = max(max(dxy0, dxy1), 0.0);\n");
// Z is the x/y offsets divided by squared radii.
fragBuilder->codeAppendf("\t\tvec2 Z = dxy * %s;\n", invRadiiXYSqdName);
break;
}
case SkRRect::kNinePatch_Type: {
const char *invRadiiLTRBSqdName;
fInvRadiiSqdUniform = args.fBuilder->addUniform(
GrGLSLProgramBuilder::kFragment_Visibility,
kVec4f_GrSLType, kHigh_GrSLPrecision,
"invRadiiLTRB",
&invRadiiLTRBSqdName);
fragBuilder->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.)
fragBuilder->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.
fragBuilder->codeAppend("\t\tfloat implicit = dot(Z, dxy) - 1.0;\n");
// grad_dot is the squared length of the gradient of the implicit.
fragBuilder->codeAppendf("\t\tfloat grad_dot = 4.0 * dot(Z, Z);\n");
// avoid calling inversesqrt on zero.
fragBuilder->codeAppend("\t\tgrad_dot = max(grad_dot, 1.0e-4);\n");
fragBuilder->codeAppendf("\t\tfloat approx_dist = implicit * inversesqrt(grad_dot);\n");
if (kFillAA_GrProcessorEdgeType == erre.getEdgeType()) {
fragBuilder->codeAppend("\t\tfloat alpha = clamp(0.5 - approx_dist, 0.0, 1.0);\n");
} else {
fragBuilder->codeAppend("\t\tfloat alpha = clamp(0.5 + approx_dist, 0.0, 1.0);\n");
}
fragBuilder->codeAppendf("\t\t%s = %s;\n", args.fOutputColor,
(GrGLSLExpr4(args.fInputColor) * GrGLSLExpr1("alpha")).c_str());
}
void GLCircularRRectEffect::emitCode(EmitArgs& args) {
const CircularRRectEffect& crre = args.fFp.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 = args.fBuilder->addUniform(GrGLSLProgramBuilder::kFragment_Visibility,
kVec4f_GrSLType, kDefault_GrSLPrecision,
"innerRect",
&rectName);
fRadiusPlusHalfUniform = args.fBuilder->addUniform(GrGLSLProgramBuilder::kFragment_Visibility,
kFloat_GrSLType, kDefault_GrSLPrecision,
"radiusPlusHalf",
&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("\t\tvec2 dxy0 = %s.xy - %s.xy;\n", rectName, fragmentPos);
fragBuilder->codeAppendf("\t\tvec2 dxy1 = %s.xy - %s.zw;\n", fragmentPos, rectName);
fragBuilder->codeAppend("\t\tvec2 dxy = max(max(dxy0, dxy1), 0.0);\n");
fragBuilder->codeAppendf("\t\tfloat alpha = clamp(%s - length(dxy), 0.0, 1.0);\n",
radiusPlusHalfName);
break;
case CircularRRectEffect::kTopLeft_CornerFlag:
fragBuilder->codeAppendf("\t\tvec2 dxy = max(%s.xy - %s.xy, 0.0);\n",
rectName, fragmentPos);
fragBuilder->codeAppendf("\t\tfloat rightAlpha = clamp(%s.z - %s.x, 0.0, 1.0);\n",
rectName, fragmentPos);
fragBuilder->codeAppendf("\t\tfloat bottomAlpha = clamp(%s.w - %s.y, 0.0, 1.0);\n",
rectName, fragmentPos);
fragBuilder->codeAppendf(
"\t\tfloat alpha = bottomAlpha * rightAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
radiusPlusHalfName);
break;
case CircularRRectEffect::kTopRight_CornerFlag:
fragBuilder->codeAppendf("\t\tvec2 dxy = max(vec2(%s.x - %s.z, %s.y - %s.y), 0.0);\n",
fragmentPos, rectName, rectName, fragmentPos);
fragBuilder->codeAppendf("\t\tfloat leftAlpha = clamp(%s.x - %s.x, 0.0, 1.0);\n",
fragmentPos, rectName);
fragBuilder->codeAppendf("\t\tfloat bottomAlpha = clamp(%s.w - %s.y, 0.0, 1.0);\n",
rectName, fragmentPos);
fragBuilder->codeAppendf(
"\t\tfloat alpha = bottomAlpha * leftAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
radiusPlusHalfName);
break;
case CircularRRectEffect::kBottomRight_CornerFlag:
fragBuilder->codeAppendf("\t\tvec2 dxy = max(%s.xy - %s.zw, 0.0);\n",
fragmentPos, rectName);
fragBuilder->codeAppendf("\t\tfloat leftAlpha = clamp(%s.x - %s.x, 0.0, 1.0);\n",
fragmentPos, rectName);
fragBuilder->codeAppendf("\t\tfloat topAlpha = clamp(%s.y - %s.y, 0.0, 1.0);\n",
fragmentPos, rectName);
fragBuilder->codeAppendf(
"\t\tfloat alpha = topAlpha * leftAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
radiusPlusHalfName);
break;
case CircularRRectEffect::kBottomLeft_CornerFlag:
fragBuilder->codeAppendf("\t\tvec2 dxy = max(vec2(%s.x - %s.x, %s.y - %s.w), 0.0);\n",
rectName, fragmentPos, fragmentPos, rectName);
fragBuilder->codeAppendf("\t\tfloat rightAlpha = clamp(%s.z - %s.x, 0.0, 1.0);\n",
rectName, fragmentPos);
fragBuilder->codeAppendf("\t\tfloat topAlpha = clamp(%s.y - %s.y, 0.0, 1.0);\n",
fragmentPos, rectName);
fragBuilder->codeAppendf(
"\t\tfloat alpha = topAlpha * rightAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
radiusPlusHalfName);
break;
case CircularRRectEffect::kLeft_CornerFlags:
fragBuilder->codeAppendf("\t\tvec2 dxy0 = %s.xy - %s.xy;\n", rectName, fragmentPos);
fragBuilder->codeAppendf("\t\tfloat dy1 = %s.y - %s.w;\n", fragmentPos, rectName);
fragBuilder->codeAppend("\t\tvec2 dxy = max(vec2(dxy0.x, max(dxy0.y, dy1)), 0.0);\n");
fragBuilder->codeAppendf("\t\tfloat rightAlpha = clamp(%s.z - %s.x, 0.0, 1.0);\n",
rectName, fragmentPos);
fragBuilder->codeAppendf(
"\t\tfloat alpha = rightAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
radiusPlusHalfName);
break;
case CircularRRectEffect::kTop_CornerFlags:
fragBuilder->codeAppendf("\t\tvec2 dxy0 = %s.xy - %s.xy;\n", rectName, fragmentPos);
fragBuilder->codeAppendf("\t\tfloat dx1 = %s.x - %s.z;\n", fragmentPos, rectName);
fragBuilder->codeAppend("\t\tvec2 dxy = max(vec2(max(dxy0.x, dx1), dxy0.y), 0.0);\n");
fragBuilder->codeAppendf("\t\tfloat bottomAlpha = clamp(%s.w - %s.y, 0.0, 1.0);\n",
rectName, fragmentPos);
fragBuilder->codeAppendf(
"\t\tfloat alpha = bottomAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
radiusPlusHalfName);
break;
case CircularRRectEffect::kRight_CornerFlags:
fragBuilder->codeAppendf("\t\tfloat dy0 = %s.y - %s.y;\n", rectName, fragmentPos);
fragBuilder->codeAppendf("\t\tvec2 dxy1 = %s.xy - %s.zw;\n", fragmentPos, rectName);
fragBuilder->codeAppend("\t\tvec2 dxy = max(vec2(dxy1.x, max(dy0, dxy1.y)), 0.0);\n");
fragBuilder->codeAppendf("\t\tfloat leftAlpha = clamp(%s.x - %s.x, 0.0, 1.0);\n",
fragmentPos, rectName);
fragBuilder->codeAppendf(
"\t\tfloat alpha = leftAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
radiusPlusHalfName);
break;
case CircularRRectEffect::kBottom_CornerFlags:
fragBuilder->codeAppendf("\t\tfloat dx0 = %s.x - %s.x;\n", rectName, fragmentPos);
fragBuilder->codeAppendf("\t\tvec2 dxy1 = %s.xy - %s.zw;\n", fragmentPos, rectName);
fragBuilder->codeAppend("\t\tvec2 dxy = max(vec2(max(dx0, dxy1.x), dxy1.y), 0.0);\n");
fragBuilder->codeAppendf("\t\tfloat topAlpha = clamp(%s.y - %s.y, 0.0, 1.0);\n",
fragmentPos, rectName);
fragBuilder->codeAppendf(
"\t\tfloat alpha = topAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
radiusPlusHalfName);
break;
}
if (kInverseFillAA_GrProcessorEdgeType == crre.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());
}