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());
}
