void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override {
const GrBitmapTextGeoProc& cte = args.fGP.cast<GrBitmapTextGeoProc>();
GrGLSLGPBuilder* pb = args.fPB;
GrGLSLVertexBuilder* vsBuilder = pb->getVertexShaderBuilder();
// emit attributes
vsBuilder->emitAttributes(cte);
// compute numbers to be hardcoded to convert texture coordinates from int to float
SkASSERT(cte.numTextures() == 1);
GrTexture* atlas = cte.textureAccess(0).getTexture();
SkASSERT(atlas && SkIsPow2(atlas->width()) && SkIsPow2(atlas->height()));
SkScalar recipWidth = 1.0f / atlas->width();
SkScalar recipHeight = 1.0f / atlas->height();
GrGLSLVertToFrag v(kVec2f_GrSLType);
pb->addVarying("TextureCoords", &v);
vsBuilder->codeAppendf("%s = vec2(%.*f, %.*f) * %s;", v.vsOut(),
GR_SIGNIFICANT_POW2_DECIMAL_DIG, recipWidth,
GR_SIGNIFICANT_POW2_DECIMAL_DIG, recipHeight,
cte.inTextureCoords()->fName);
// Setup pass through color
if (!cte.colorIgnored()) {
if (cte.hasVertexColor()) {
pb->addPassThroughAttribute(cte.inColor(), args.fOutputColor);
} else {
this->setupUniformColor(pb, args.fOutputColor, &fColorUniform);
}
}
// Setup position
this->setupPosition(pb, gpArgs, cte.inPosition()->fName);
// emit transforms
this->emitTransforms(args.fPB, gpArgs->fPositionVar, cte.inPosition()->fName,
cte.localMatrix(), args.fTransformsIn, args.fTransformsOut);
GrGLSLFragmentBuilder* fsBuilder = pb->getFragmentShaderBuilder();
if (cte.maskFormat() == kARGB_GrMaskFormat) {
fsBuilder->codeAppendf("%s = ", args.fOutputColor);
fsBuilder->appendTextureLookupAndModulate(args.fOutputColor,
args.fSamplers[0],
v.fsIn(),
kVec2f_GrSLType);
fsBuilder->codeAppend(";");
fsBuilder->codeAppendf("%s = vec4(1);", args.fOutputCoverage);
} else {
fsBuilder->codeAppendf("%s = ", args.fOutputCoverage);
fsBuilder->appendTextureLookup(args.fSamplers[0], v.fsIn(), kVec2f_GrSLType);
fsBuilder->codeAppend(";");
if (cte.maskFormat() == kA565_GrMaskFormat) {
// set alpha to be max of rgb coverage
fsBuilder->codeAppendf("%s.a = max(max(%s.r, %s.g), %s.b);",
args.fOutputCoverage, args.fOutputCoverage,
args.fOutputCoverage, args.fOutputCoverage);
}
}
}
void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override {
const MSAAQuadProcessor& qp = args.fGP.cast<MSAAQuadProcessor>();
GrGLSLVertexBuilder* vsBuilder = args.fVertBuilder;
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
// emit attributes
varyingHandler->emitAttributes(qp);
varyingHandler->addPassThroughAttribute(qp.inColor(), args.fOutputColor);
GrGLSLVertToFrag uv(kVec2f_GrSLType);
varyingHandler->addVarying("uv", &uv, kHigh_GrSLPrecision);
vsBuilder->codeAppendf("%s = %s;", uv.vsOut(), qp.inUV()->fName);
// Setup position
this->setupPosition(vsBuilder, uniformHandler, gpArgs, qp.inPosition()->fName,
qp.viewMatrix(), &fViewMatrixUniform);
// emit transforms
this->emitTransforms(vsBuilder, varyingHandler, uniformHandler, gpArgs->fPositionVar,
qp.inPosition()->fName, SkMatrix::I(), args.fTransformsIn,
args.fTransformsOut);
GrGLSLPPFragmentBuilder* fsBuilder = args.fFragBuilder;
fsBuilder->codeAppendf("if (%s.x * %s.x >= %s.y) discard;", uv.fsIn(), uv.fsIn(),
uv.fsIn());
fsBuilder->codeAppendf("%s = vec4(1.0);", args.fOutputCoverage);
}
void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override {
const QuadEdgeEffect& qe = args.fGP.cast<QuadEdgeEffect>();
GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
// emit attributes
varyingHandler->emitAttributes(qe);
GrGLSLVertToFrag v(kVec4f_GrSLType);
varyingHandler->addVarying("QuadEdge", &v);
vertBuilder->codeAppendf("%s = %s;", v.vsOut(), qe.inQuadEdge()->fName);
GrGLSLPPFragmentBuilder* fragBuilder = args.fFragBuilder;
// Setup pass through color
if (!qe.colorIgnored()) {
this->setupUniformColor(fragBuilder, uniformHandler, args.fOutputColor,
&fColorUniform);
}
// Setup position
this->setupPosition(vertBuilder, gpArgs, qe.inPosition()->fName);
// emit transforms
this->emitTransforms(vertBuilder,
varyingHandler,
uniformHandler,
gpArgs->fPositionVar,
qe.inPosition()->fName,
qe.localMatrix(),
args.fTransformsIn,
args.fTransformsOut);
SkAssertResult(fragBuilder->enableFeature(
GrGLSLFragmentShaderBuilder::kStandardDerivatives_GLSLFeature));
fragBuilder->codeAppendf("float edgeAlpha;");
// keep the derivative instructions outside the conditional
fragBuilder->codeAppendf("vec2 duvdx = dFdx(%s.xy);", v.fsIn());
fragBuilder->codeAppendf("vec2 duvdy = dFdy(%s.xy);", v.fsIn());
fragBuilder->codeAppendf("if (%s.z > 0.0 && %s.w > 0.0) {", v.fsIn(), v.fsIn());
// today we know z and w are in device space. We could use derivatives
fragBuilder->codeAppendf("edgeAlpha = min(min(%s.z, %s.w) + 0.5, 1.0);", v.fsIn(),
v.fsIn());
fragBuilder->codeAppendf ("} else {");
fragBuilder->codeAppendf("vec2 gF = vec2(2.0*%s.x*duvdx.x - duvdx.y,"
" 2.0*%s.x*duvdy.x - duvdy.y);",
v.fsIn(), v.fsIn());
fragBuilder->codeAppendf("edgeAlpha = (%s.x*%s.x - %s.y);", v.fsIn(), v.fsIn(),
v.fsIn());
fragBuilder->codeAppendf("edgeAlpha = "
"clamp(0.5 - edgeAlpha / length(gF), 0.0, 1.0);}");
fragBuilder->codeAppendf("%s = vec4(edgeAlpha);", args.fOutputCoverage);
}
void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) final {
const GrPipelineDynamicStateTestProcessor& mp =
args.fGP.cast<GrPipelineDynamicStateTestProcessor>();
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
varyingHandler->emitAttributes(mp);
varyingHandler->addPassThroughAttribute(&mp.fColor, args.fOutputColor);
GrGLSLVertexBuilder* v = args.fVertBuilder;
v->codeAppendf("vec2 vertex = %s;", mp.fVertex.fName);
gpArgs->fPositionVar.set(kVec2f_GrSLType, "vertex");
GrGLSLPPFragmentBuilder* f = args.fFragBuilder;
f->codeAppendf("%s = vec4(1);", args.fOutputCoverage);
}
void GrGLQuadEffect::onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) {
GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
const GrQuadEffect& gp = args.fGP.cast<GrQuadEffect>();
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
// emit attributes
varyingHandler->emitAttributes(gp);
GrGLSLVertToFrag v(kVec4f_GrSLType);
varyingHandler->addVarying("HairQuadEdge", &v);
vertBuilder->codeAppendf("%s = %s;", v.vsOut(), gp.inHairQuadEdge()->fName);
GrGLSLPPFragmentBuilder* fragBuilder = args.fFragBuilder;
// Setup pass through color
this->setupUniformColor(fragBuilder, uniformHandler, args.fOutputColor, &fColorUniform);
// Setup position
this->setupPosition(vertBuilder,
uniformHandler,
gpArgs,
gp.inPosition()->fName,
gp.viewMatrix(),
&fViewMatrixUniform);
// emit transforms with position
this->emitTransforms(vertBuilder,
varyingHandler,
uniformHandler,
gpArgs->fPositionVar,
gp.inPosition()->fName,
gp.localMatrix(),
args.fFPCoordTransformHandler);
fragBuilder->codeAppendf("float edgeAlpha;");
switch (fEdgeType) {
case kHairlineAA_GrProcessorEdgeType: {
fragBuilder->codeAppendf("vec2 duvdx = dFdx(%s.xy);", v.fsIn());
fragBuilder->codeAppendf("vec2 duvdy = dFdy(%s.xy);", v.fsIn());
fragBuilder->codeAppendf("vec2 gF = vec2(2.0 * %s.x * duvdx.x - duvdx.y,"
" 2.0 * %s.x * duvdy.x - duvdy.y);",
v.fsIn(), v.fsIn());
fragBuilder->codeAppendf("edgeAlpha = (%s.x * %s.x - %s.y);",
v.fsIn(), v.fsIn(), v.fsIn());
fragBuilder->codeAppend("edgeAlpha = sqrt(edgeAlpha * edgeAlpha / dot(gF, gF));");
fragBuilder->codeAppend("edgeAlpha = max(1.0 - edgeAlpha, 0.0);");
// Add line below for smooth cubic ramp
// fragBuilder->codeAppend("edgeAlpha = edgeAlpha*edgeAlpha*(3.0-2.0*edgeAlpha);");
break;
}
case kFillAA_GrProcessorEdgeType: {
fragBuilder->codeAppendf("vec2 duvdx = dFdx(%s.xy);", v.fsIn());
fragBuilder->codeAppendf("vec2 duvdy = dFdy(%s.xy);", v.fsIn());
fragBuilder->codeAppendf("vec2 gF = vec2(2.0 * %s.x * duvdx.x - duvdx.y,"
" 2.0 * %s.x * duvdy.x - duvdy.y);",
v.fsIn(), v.fsIn());
fragBuilder->codeAppendf("edgeAlpha = (%s.x * %s.x - %s.y);",
v.fsIn(), v.fsIn(), v.fsIn());
fragBuilder->codeAppend("edgeAlpha = edgeAlpha / sqrt(dot(gF, gF));");
fragBuilder->codeAppend("edgeAlpha = clamp(0.5 - edgeAlpha, 0.0, 1.0);");
// Add line below for smooth cubic ramp
// fragBuilder->codeAppend("edgeAlpha = edgeAlpha*edgeAlpha*(3.0-2.0*edgeAlpha);");
break;
}
case kFillBW_GrProcessorEdgeType: {
fragBuilder->codeAppendf("edgeAlpha = (%s.x * %s.x - %s.y);",
v.fsIn(), v.fsIn(), v.fsIn());
fragBuilder->codeAppend("edgeAlpha = float(edgeAlpha < 0.0);");
break;
}
default:
SkFAIL("Shouldn't get here");
}
if (0xff != gp.coverageScale()) {
const char* coverageScale;
fCoverageScaleUniform = uniformHandler->addUniform(kFragment_GrShaderFlag,
kFloat_GrSLType,
kDefault_GrSLPrecision,
"Coverage",
&coverageScale);
fragBuilder->codeAppendf("%s = vec4(%s * edgeAlpha);", args.fOutputCoverage, coverageScale);
} else {
fragBuilder->codeAppendf("%s = vec4(edgeAlpha);", args.fOutputCoverage);
}
}
void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override {
const DefaultGeoProc& gp = args.fGP.cast<DefaultGeoProc>();
GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
// emit attributes
varyingHandler->emitAttributes(gp);
// Setup pass through color
if (gp.hasVertexColor()) {
GrGLSLVarying varying(kHalf4_GrSLType);
varyingHandler->addVarying("color", &varying);
// There are several optional steps to process the color. Start with the attribute:
vertBuilder->codeAppendf("half4 color = %s;", gp.inColor()->fName);
// Linearize
if (gp.linearizeColor()) {
SkString srgbFuncName;
static const GrShaderVar gSrgbArgs[] = {
GrShaderVar("x", kHalf_GrSLType),
};
vertBuilder->emitFunction(kHalf_GrSLType,
"srgb_to_linear",
SK_ARRAY_COUNT(gSrgbArgs),
gSrgbArgs,
"return (x <= 0.04045) ? (x / 12.92) "
": pow((x + 0.055) / 1.055, 2.4);",
&srgbFuncName);
vertBuilder->codeAppendf("color = half4(%s(%s.r), %s(%s.g), %s(%s.b), %s.a);",
srgbFuncName.c_str(), gp.inColor()->fName,
srgbFuncName.c_str(), gp.inColor()->fName,
srgbFuncName.c_str(), gp.inColor()->fName,
gp.inColor()->fName);
}
// For SkColor, do a red/blue swap and premul
if (gp.fFlags & kColorAttributeIsSkColor_GPFlag) {
vertBuilder->codeAppend("color = half4(color.a * color.bgr, color.a);");
}
// Do color-correction to destination gamut
if (gp.linearizeColor()) {
fColorSpaceHelper.emitCode(uniformHandler, gp.fColorSpaceXform.get(),
kVertex_GrShaderFlag);
if (fColorSpaceHelper.isValid()) {
SkString xformedColor;
vertBuilder->appendColorGamutXform(&xformedColor, "color",
&fColorSpaceHelper);
vertBuilder->codeAppendf("color = %s;", xformedColor.c_str());
}
}
vertBuilder->codeAppendf("%s = color;\n", varying.vsOut());
fragBuilder->codeAppendf("%s = %s;", args.fOutputColor, varying.fsIn());
} else {
this->setupUniformColor(fragBuilder, uniformHandler, args.fOutputColor,
&fColorUniform);
}
// Setup position
this->writeOutputPosition(vertBuilder,
uniformHandler,
gpArgs,
gp.inPosition()->fName,
gp.viewMatrix(),
&fViewMatrixUniform);
if (gp.hasExplicitLocalCoords()) {
// emit transforms with explicit local coords
this->emitTransforms(vertBuilder,
varyingHandler,
uniformHandler,
gp.inLocalCoords()->asShaderVar(),
gp.localMatrix(),
args.fFPCoordTransformHandler);
} else {
// emit transforms with position
this->emitTransforms(vertBuilder,
varyingHandler,
uniformHandler,
gp.inPosition()->asShaderVar(),
gp.localMatrix(),
args.fFPCoordTransformHandler);
}
// Setup coverage as pass through
if (gp.hasVertexCoverage()) {
fragBuilder->codeAppendf("half alpha = 1.0;");
varyingHandler->addPassThroughAttribute(gp.inCoverage(), "alpha");
fragBuilder->codeAppendf("%s = half4(alpha);", args.fOutputCoverage);
} else if (gp.coverage() == 0xff) {
fragBuilder->codeAppendf("%s = half4(1);", args.fOutputCoverage);
} else {
const char* fragCoverage;
fCoverageUniform = uniformHandler->addUniform(kFragment_GrShaderFlag,
kHalf_GrSLType,
"Coverage",
&fragCoverage);
fragBuilder->codeAppendf("%s = half4(%s);", args.fOutputCoverage, fragCoverage);
}
}
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 onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override {
const auto& proc = args.fGP.cast<Processor>();
bool useHWDerivatives = (proc.fFlags & Flags::kUseHWDerivatives);
SkASSERT(proc.vertexStride() == sizeof(CoverageVertex));
GrGLSLVaryingHandler* varyings = args.fVaryingHandler;
varyings->emitAttributes(proc);
varyings->addPassThroughAttribute(*proc.fColorAttrib, args.fOutputColor,
GrGLSLVaryingHandler::Interpolation::kCanBeFlat);
// Emit the vertex shader.
GrGLSLVertexBuilder* v = args.fVertBuilder;
// Unpack vertex attribs.
v->codeAppend("float2 corner = corner_and_radius_outsets.xy;");
v->codeAppend("float2 radius_outset = corner_and_radius_outsets.zw;");
v->codeAppend("float2 aa_bloat_direction = aa_bloat_and_coverage.xy;");
v->codeAppend("float coverage = aa_bloat_and_coverage.z;");
v->codeAppend("float is_linear_coverage = aa_bloat_and_coverage.w;");
// Find the amount to bloat each edge for AA (in source space).
v->codeAppend("float2 pixellength = inversesqrt("
"float2(dot(skew.xz, skew.xz), dot(skew.yw, skew.yw)));");
v->codeAppend("float4 normalized_axis_dirs = skew * pixellength.xyxy;");
v->codeAppend("float2 axiswidths = (abs(normalized_axis_dirs.xy) + "
"abs(normalized_axis_dirs.zw));");
v->codeAppend("float2 aa_bloatradius = axiswidths * pixellength * .5;");
// Identify our radii.
v->codeAppend("float4 radii_and_neighbors = radii_selector"
"* float4x4(radii_x, radii_y, radii_x.yxwz, radii_y.wzyx);");
v->codeAppend("float2 radii = radii_and_neighbors.xy;");
v->codeAppend("float2 neighbor_radii = radii_and_neighbors.zw;");
v->codeAppend("if (any(greaterThan(aa_bloatradius, float2(1)))) {");
// The rrect is more narrow than an AA coverage ramp. We can't draw as-is
// or else opposite AA borders will overlap. Instead, fudge the size up to
// the width of a coverage ramp, and then reduce total coverage to make
// the rect appear more thin.
v->codeAppend( "corner = max(abs(corner), aa_bloatradius) * sign(corner);");
v->codeAppend( "coverage /= max(aa_bloatradius.x, 1) * max(aa_bloatradius.y, 1);");
// Set radii to zero to ensure we take the "linear coverage" codepath.
// (The "coverage" variable only has effect in the linear codepath.)
v->codeAppend( "radii = float2(0);");
v->codeAppend("}");
v->codeAppend("if (any(lessThan(radii, aa_bloatradius * 1.25))) {");
// The radii are very small. Demote this arc to a sharp 90 degree corner.
v->codeAppend( "radii = aa_bloatradius;");
// Snap octagon vertices to the corner of the bounding box.
v->codeAppend( "radius_outset = floor(abs(radius_outset)) * radius_outset;");
v->codeAppend( "is_linear_coverage = 1;");
v->codeAppend("} else {");
// Don't let radii get smaller than a pixel.
v->codeAppend( "radii = clamp(radii, pixellength, 2 - pixellength);");
v->codeAppend( "neighbor_radii = clamp(neighbor_radii, pixellength, 2 - pixellength);");
// Don't let neighboring radii get closer together than 1/16 pixel.
v->codeAppend( "float2 spacing = 2 - radii - neighbor_radii;");
v->codeAppend( "float2 extra_pad = max(pixellength * .0625 - spacing, float2(0));");
v->codeAppend( "radii -= extra_pad * .5;");
v->codeAppend("}");
// Find our vertex position, adjusted for radii and bloated for AA. Our rect is drawn in
// normalized [-1,-1,+1,+1] space.
v->codeAppend("float2 aa_outset = aa_bloat_direction.xy * aa_bloatradius;");
v->codeAppend("float2 vertexpos = corner + radius_outset * radii + aa_outset;");
// Emit transforms.
GrShaderVar localCoord("", kFloat2_GrSLType);
if (proc.fFlags & Flags::kHasLocalCoords) {
v->codeAppend("float2 localcoord = (local_rect.xy * (1 - vertexpos) + "
"local_rect.zw * (1 + vertexpos)) * .5;");
localCoord.set(kFloat2_GrSLType, "localcoord");
}
this->emitTransforms(v, varyings, args.fUniformHandler, localCoord,
args.fFPCoordTransformHandler);
// Transform to device space.
SkASSERT(!(proc.fFlags & Flags::kHasPerspective));
v->codeAppend("float2x2 skewmatrix = float2x2(skew.xy, skew.zw);");
v->codeAppend("float2 devcoord = vertexpos * skewmatrix + translate;");
gpArgs->fPositionVar.set(kFloat2_GrSLType, "devcoord");
// Setup interpolants for coverage.
GrGLSLVarying arcCoord(useHWDerivatives ? kFloat2_GrSLType : kFloat4_GrSLType);
varyings->addVarying("arccoord", &arcCoord);
v->codeAppend("if (0 != is_linear_coverage) {");
// We are a non-corner piece: Set x=0 to indicate built-in coverage, and
// interpolate linear coverage across y.
v->codeAppendf( "%s.xy = float2(0, coverage);", arcCoord.vsOut());
v->codeAppend("} else {");
// Find the normalized arc coordinates for our corner ellipse.
// (i.e., the coordinate system where x^2 + y^2 == 1).
v->codeAppend( "float2 arccoord = 1 - abs(radius_outset) + aa_outset/radii * corner;");
// We are a corner piece: Interpolate the arc coordinates for coverage.
// Emit x+1 to ensure no pixel in the arc has a x value of 0 (since x=0
// instructs the fragment shader to use linear coverage).
v->codeAppendf( "%s.xy = float2(arccoord.x+1, arccoord.y);", arcCoord.vsOut());
if (!useHWDerivatives) {
// The gradient is order-1: Interpolate it across arccoord.zw.
v->codeAppendf("float2x2 derivatives = inverse(skewmatrix);");
v->codeAppendf("%s.zw = derivatives * (arccoord/radii * 2);", arcCoord.vsOut());
}
v->codeAppend("}");
// Emit the fragment shader.
GrGLSLFPFragmentBuilder* f = args.fFragBuilder;
f->codeAppendf("float x_plus_1=%s.x, y=%s.y;", arcCoord.fsIn(), arcCoord.fsIn());
f->codeAppendf("half coverage;");
f->codeAppendf("if (0 == x_plus_1) {");
f->codeAppendf( "coverage = half(y);"); // We are a non-arc pixel (linear coverage).
f->codeAppendf("} else {");
f->codeAppendf( "float fn = x_plus_1 * (x_plus_1 - 2);"); // fn = (x+1)*(x-1) = x^2-1
f->codeAppendf( "fn = fma(y,y, fn);"); // fn = x^2 + y^2 - 1
if (useHWDerivatives) {
f->codeAppendf("float fnwidth = fwidth(fn);");
} else {
// The gradient is interpolated across arccoord.zw.
f->codeAppendf("float gx=%s.z, gy=%s.w;", arcCoord.fsIn(), arcCoord.fsIn());
f->codeAppendf("float fnwidth = abs(gx) + abs(gy);");
}
f->codeAppendf( "half d = half(fn/fnwidth);");
f->codeAppendf( "coverage = clamp(.5 - d, 0, 1);");
f->codeAppendf("}");
f->codeAppendf("%s = half4(coverage);", args.fOutputCoverage);
}
void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override{
const GrDistanceFieldA8TextGeoProc& dfTexEffect =
args.fGP.cast<GrDistanceFieldA8TextGeoProc>();
GrGLSLPPFragmentBuilder* fragBuilder = args.fFragBuilder;
SkAssertResult(fragBuilder->enableFeature(
GrGLSLFragmentShaderBuilder::kStandardDerivatives_GLSLFeature));
GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
// emit attributes
varyingHandler->emitAttributes(dfTexEffect);
#ifdef SK_GAMMA_APPLY_TO_A8
// adjust based on gamma
const char* distanceAdjustUniName = nullptr;
// width, height, 1/(3*width)
fDistanceAdjustUni = uniformHandler->addUniform(kFragment_GrShaderFlag,
kFloat_GrSLType, kDefault_GrSLPrecision,
"DistanceAdjust", &distanceAdjustUniName);
#endif
// Setup pass through color
if (!dfTexEffect.colorIgnored()) {
varyingHandler->addPassThroughAttribute(dfTexEffect.inColor(), args.fOutputColor);
}
// Setup position
this->setupPosition(vertBuilder,
uniformHandler,
gpArgs,
dfTexEffect.inPosition()->fName,
dfTexEffect.viewMatrix(),
&fViewMatrixUniform);
// emit transforms
this->emitTransforms(vertBuilder,
varyingHandler,
uniformHandler,
gpArgs->fPositionVar,
dfTexEffect.inPosition()->fName,
args.fTransformsIn,
args.fTransformsOut);
// add varyings
GrGLSLVertToFrag recipScale(kFloat_GrSLType);
GrGLSLVertToFrag uv(kVec2f_GrSLType);
bool isUniformScale = (dfTexEffect.getFlags() & kUniformScale_DistanceFieldEffectMask) ==
kUniformScale_DistanceFieldEffectMask;
bool isSimilarity = SkToBool(dfTexEffect.getFlags() & kSimilarity_DistanceFieldEffectFlag);
varyingHandler->addVarying("TextureCoords", &uv, kHigh_GrSLPrecision);
vertBuilder->codeAppendf("%s = %s;", uv.vsOut(), dfTexEffect.inTextureCoords()->fName);
// compute numbers to be hardcoded to convert texture coordinates from float to int
SkASSERT(dfTexEffect.numTextures() == 1);
GrTexture* atlas = dfTexEffect.textureAccess(0).getTexture();
SkASSERT(atlas && SkIsPow2(atlas->width()) && SkIsPow2(atlas->height()));
GrGLSLVertToFrag st(kVec2f_GrSLType);
varyingHandler->addVarying("IntTextureCoords", &st, kHigh_GrSLPrecision);
vertBuilder->codeAppendf("%s = vec2(%d, %d) * %s;", st.vsOut(),
atlas->width(), atlas->height(),
dfTexEffect.inTextureCoords()->fName);
// Use highp to work around aliasing issues
fragBuilder->codeAppend(GrGLSLShaderVar::PrecisionString(args.fGLSLCaps,
kHigh_GrSLPrecision));
fragBuilder->codeAppendf("vec2 uv = %s;\n", uv.fsIn());
fragBuilder->codeAppend("\tfloat texColor = ");
fragBuilder->appendTextureLookup(args.fSamplers[0],
"uv",
kVec2f_GrSLType);
fragBuilder->codeAppend(".r;\n");
fragBuilder->codeAppend("\tfloat distance = "
SK_DistanceFieldMultiplier "*(texColor - " SK_DistanceFieldThreshold ");");
#ifdef SK_GAMMA_APPLY_TO_A8
// adjust width based on gamma
fragBuilder->codeAppendf("distance -= %s;", distanceAdjustUniName);
#endif
fragBuilder->codeAppend("float afwidth;");
if (isUniformScale) {
// For uniform scale, we adjust for the effect of the transformation on the distance
// by using the length of the gradient of the t coordinate in the y direction.
// We use st coordinates to ensure we're mapping 1:1 from texel space to pixel space.
// We use the y gradient because there is a bug in the Mali 400 in the x direction.
// this gives us a smooth step across approximately one fragment
fragBuilder->codeAppendf("afwidth = abs(" SK_DistanceFieldAAFactor "*dFdy(%s.y));",
st.fsIn());
} else if (isSimilarity) {
// For similarity transform, we adjust the effect of the transformation on the distance
// by using the length of the gradient of the texture coordinates. We use st coordinates
// to ensure we're mapping 1:1 from texel space to pixel space.
// We use the y gradient because there is a bug in the Mali 400 in the x direction.
// this gives us a smooth step across approximately one fragment
fragBuilder->codeAppendf("float st_grad_len = length(dFdy(%s));", st.fsIn());
fragBuilder->codeAppend("afwidth = abs(" SK_DistanceFieldAAFactor "*st_grad_len);");
} else {
// For general transforms, to determine the amount of correction we multiply a unit
// vector pointing along the SDF gradient direction by the Jacobian of the st coords
// (which is the inverse transform for this fragment) and take the length of the result.
fragBuilder->codeAppend("vec2 dist_grad = vec2(dFdx(distance), dFdy(distance));");
// the length of the gradient may be 0, so we need to check for this
// this also compensates for the Adreno, which likes to drop tiles on division by 0
fragBuilder->codeAppend("float dg_len2 = dot(dist_grad, dist_grad);");
fragBuilder->codeAppend("if (dg_len2 < 0.0001) {");
fragBuilder->codeAppend("dist_grad = vec2(0.7071, 0.7071);");
fragBuilder->codeAppend("} else {");
fragBuilder->codeAppend("dist_grad = dist_grad*inversesqrt(dg_len2);");
fragBuilder->codeAppend("}");
fragBuilder->codeAppendf("vec2 Jdx = dFdx(%s);", st.fsIn());
fragBuilder->codeAppendf("vec2 Jdy = dFdy(%s);", st.fsIn());
fragBuilder->codeAppend("vec2 grad = vec2(dist_grad.x*Jdx.x + dist_grad.y*Jdy.x,");
fragBuilder->codeAppend(" dist_grad.x*Jdx.y + dist_grad.y*Jdy.y);");
// this gives us a smooth step across approximately one fragment
fragBuilder->codeAppend("afwidth = " SK_DistanceFieldAAFactor "*length(grad);");
}
fragBuilder->codeAppend("float val = smoothstep(-afwidth, afwidth, distance);");
fragBuilder->codeAppendf("%s = vec4(val);", args.fOutputCoverage);
}
void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override{
const GrDistanceFieldPathGeoProc& dfTexEffect = args.fGP.cast<GrDistanceFieldPathGeoProc>();
GrGLSLFragmentBuilder* fragBuilder = args.fFragBuilder;
SkAssertResult(fragBuilder->enableFeature(
GrGLSLFragmentShaderBuilder::kStandardDerivatives_GLSLFeature));
GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
// emit attributes
varyingHandler->emitAttributes(dfTexEffect);
GrGLSLVertToFrag v(kVec2f_GrSLType);
varyingHandler->addVarying("TextureCoords", &v, kHigh_GrSLPrecision);
// setup pass through color
if (!dfTexEffect.colorIgnored()) {
varyingHandler->addPassThroughAttribute(dfTexEffect.inColor(), args.fOutputColor);
}
vertBuilder->codeAppendf("%s = %s;", v.vsOut(), dfTexEffect.inTextureCoords()->fName);
// Setup position
this->setupPosition(vertBuilder,
uniformHandler,
gpArgs,
dfTexEffect.inPosition()->fName,
dfTexEffect.viewMatrix(),
&fViewMatrixUniform);
// emit transforms
this->emitTransforms(vertBuilder,
varyingHandler,
uniformHandler,
gpArgs->fPositionVar,
dfTexEffect.inPosition()->fName,
args.fTransformsIn,
args.fTransformsOut);
const char* textureSizeUniName = nullptr;
fTextureSizeUni = uniformHandler->addUniform(GrGLSLUniformHandler::kFragment_Visibility,
kVec2f_GrSLType, kDefault_GrSLPrecision,
"TextureSize", &textureSizeUniName);
// Use highp to work around aliasing issues
fragBuilder->codeAppend(GrGLSLShaderVar::PrecisionString(args.fGLSLCaps,
kHigh_GrSLPrecision));
fragBuilder->codeAppendf("vec2 uv = %s;", v.fsIn());
fragBuilder->codeAppend("float texColor = ");
fragBuilder->appendTextureLookup(args.fSamplers[0],
"uv",
kVec2f_GrSLType);
fragBuilder->codeAppend(".r;");
fragBuilder->codeAppend("float distance = "
SK_DistanceFieldMultiplier "*(texColor - " SK_DistanceFieldThreshold ");");
fragBuilder->codeAppend(GrGLSLShaderVar::PrecisionString(args.fGLSLCaps,
kHigh_GrSLPrecision));
fragBuilder->codeAppendf("vec2 st = uv*%s;", textureSizeUniName);
fragBuilder->codeAppend("float afwidth;");
if (dfTexEffect.getFlags() & kSimilarity_DistanceFieldEffectFlag) {
// For uniform scale, we adjust for the effect of the transformation on the distance
// by using the length of the gradient of the texture coordinates. We use st coordinates
// to ensure we're mapping 1:1 from texel space to pixel space.
// this gives us a smooth step across approximately one fragment
fragBuilder->codeAppend("afwidth = abs(" SK_DistanceFieldAAFactor "*dFdy(st.y));");
} else {
// For general transforms, to determine the amount of correction we multiply a unit
// vector pointing along the SDF gradient direction by the Jacobian of the st coords
// (which is the inverse transform for this fragment) and take the length of the result.
fragBuilder->codeAppend("vec2 dist_grad = vec2(dFdx(distance), dFdy(distance));");
// the length of the gradient may be 0, so we need to check for this
// this also compensates for the Adreno, which likes to drop tiles on division by 0
fragBuilder->codeAppend("float dg_len2 = dot(dist_grad, dist_grad);");
fragBuilder->codeAppend("if (dg_len2 < 0.0001) {");
fragBuilder->codeAppend("dist_grad = vec2(0.7071, 0.7071);");
fragBuilder->codeAppend("} else {");
fragBuilder->codeAppend("dist_grad = dist_grad*inversesqrt(dg_len2);");
fragBuilder->codeAppend("}");
fragBuilder->codeAppend("vec2 Jdx = dFdx(st);");
fragBuilder->codeAppend("vec2 Jdy = dFdy(st);");
fragBuilder->codeAppend("vec2 grad = vec2(dist_grad.x*Jdx.x + dist_grad.y*Jdy.x,");
fragBuilder->codeAppend(" dist_grad.x*Jdx.y + dist_grad.y*Jdy.y);");
// this gives us a smooth step across approximately one fragment
fragBuilder->codeAppend("afwidth = " SK_DistanceFieldAAFactor "*length(grad);");
}
fragBuilder->codeAppend("float val = smoothstep(-afwidth, afwidth, distance);");
fragBuilder->codeAppendf("%s = vec4(val);", args.fOutputCoverage);
}
void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override{
const GrDistanceFieldPathGeoProc& dfTexEffect = args.fGP.cast<GrDistanceFieldPathGeoProc>();
GrGLSLPPFragmentBuilder* fragBuilder = args.fFragBuilder;
SkAssertResult(fragBuilder->enableFeature(
GrGLSLFragmentShaderBuilder::kStandardDerivatives_GLSLFeature));
GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
// emit attributes
varyingHandler->emitAttributes(dfTexEffect);
GrGLSLVertToFrag v(kVec2f_GrSLType);
varyingHandler->addVarying("TextureCoords", &v, kHigh_GrSLPrecision);
// setup pass through color
if (!dfTexEffect.colorIgnored()) {
varyingHandler->addPassThroughAttribute(dfTexEffect.inColor(), args.fOutputColor);
}
vertBuilder->codeAppendf("%s = %s;", v.vsOut(), dfTexEffect.inTextureCoords()->fName);
// Setup position
this->setupPosition(vertBuilder,
uniformHandler,
gpArgs,
dfTexEffect.inPosition()->fName,
dfTexEffect.viewMatrix(),
&fViewMatrixUniform);
// emit transforms
this->emitTransforms(vertBuilder,
varyingHandler,
uniformHandler,
gpArgs->fPositionVar,
dfTexEffect.inPosition()->fName,
args.fFPCoordTransformHandler);
const char* textureSizeUniName = nullptr;
fTextureSizeUni = uniformHandler->addUniform(kFragment_GrShaderFlag,
kVec2f_GrSLType, kDefault_GrSLPrecision,
"TextureSize", &textureSizeUniName);
// Use highp to work around aliasing issues
fragBuilder->appendPrecisionModifier(kHigh_GrSLPrecision);
fragBuilder->codeAppendf("vec2 uv = %s;", v.fsIn());
fragBuilder->codeAppend("float texColor = ");
fragBuilder->appendTextureLookup(args.fTexSamplers[0],
"uv",
kVec2f_GrSLType);
fragBuilder->codeAppend(".r;");
fragBuilder->codeAppend("float distance = "
SK_DistanceFieldMultiplier "*(texColor - " SK_DistanceFieldThreshold ");");
fragBuilder->appendPrecisionModifier(kHigh_GrSLPrecision);
fragBuilder->codeAppendf("vec2 st = uv*%s;", textureSizeUniName);
fragBuilder->codeAppend("float afwidth;");
bool isUniformScale = (dfTexEffect.getFlags() & kUniformScale_DistanceFieldEffectMask) ==
kUniformScale_DistanceFieldEffectMask;
bool isSimilarity = SkToBool(dfTexEffect.getFlags() & kSimilarity_DistanceFieldEffectFlag);
bool isGammaCorrect =
SkToBool(dfTexEffect.getFlags() & kGammaCorrect_DistanceFieldEffectFlag);
if (isUniformScale) {
// For uniform scale, we adjust for the effect of the transformation on the distance
// by using the length of the gradient of the t coordinate in the y direction.
// We use st coordinates to ensure we're mapping 1:1 from texel space to pixel space.
// this gives us a smooth step across approximately one fragment
#ifdef SK_VULKAN
fragBuilder->codeAppend("afwidth = abs(" SK_DistanceFieldAAFactor "*dFdx(st.x));");
#else
// We use the y gradient because there is a bug in the Mali 400 in the x direction.
fragBuilder->codeAppend("afwidth = abs(" SK_DistanceFieldAAFactor "*dFdy(st.y));");
#endif
} else if (isSimilarity) {
// For similarity transform, we adjust the effect of the transformation on the distance
// by using the length of the gradient of the texture coordinates. We use st coordinates
// to ensure we're mapping 1:1 from texel space to pixel space.
// this gives us a smooth step across approximately one fragment
#ifdef SK_VULKAN
fragBuilder->codeAppend("float st_grad_len = length(dFdx(st));");
#else
// We use the y gradient because there is a bug in the Mali 400 in the x direction.
fragBuilder->codeAppend("float st_grad_len = length(dFdy(st));");
#endif
fragBuilder->codeAppend("afwidth = abs(" SK_DistanceFieldAAFactor "*st_grad_len);");
} else {
// For general transforms, to determine the amount of correction we multiply a unit
// vector pointing along the SDF gradient direction by the Jacobian of the st coords
// (which is the inverse transform for this fragment) and take the length of the result.
fragBuilder->codeAppend("vec2 dist_grad = vec2(dFdx(distance), dFdy(distance));");
// the length of the gradient may be 0, so we need to check for this
// this also compensates for the Adreno, which likes to drop tiles on division by 0
fragBuilder->codeAppend("float dg_len2 = dot(dist_grad, dist_grad);");
fragBuilder->codeAppend("if (dg_len2 < 0.0001) {");
fragBuilder->codeAppend("dist_grad = vec2(0.7071, 0.7071);");
fragBuilder->codeAppend("} else {");
fragBuilder->codeAppend("dist_grad = dist_grad*inversesqrt(dg_len2);");
fragBuilder->codeAppend("}");
fragBuilder->codeAppend("vec2 Jdx = dFdx(st);");
fragBuilder->codeAppend("vec2 Jdy = dFdy(st);");
fragBuilder->codeAppend("vec2 grad = vec2(dist_grad.x*Jdx.x + dist_grad.y*Jdy.x,");
fragBuilder->codeAppend(" dist_grad.x*Jdx.y + dist_grad.y*Jdy.y);");
// this gives us a smooth step across approximately one fragment
fragBuilder->codeAppend("afwidth = " SK_DistanceFieldAAFactor "*length(grad);");
}
// The smoothstep falloff compensates for the non-linear sRGB response curve. If we are
// doing gamma-correct rendering (to an sRGB or F16 buffer), then we actually want distance
// mapped linearly to coverage, so use a linear step:
if (isGammaCorrect) {
fragBuilder->codeAppend(
"float val = clamp(distance + afwidth / (2.0 * afwidth), 0.0, 1.0);");
} else {
fragBuilder->codeAppend("float val = smoothstep(-afwidth, afwidth, distance);");
}
fragBuilder->codeAppendf("%s = vec4(val);", args.fOutputCoverage);
}
void GrGLCubicEffect::onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) {
GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
const GrCubicEffect& gp = args.fGP.cast<GrCubicEffect>();
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
// emit attributes
varyingHandler->emitAttributes(gp);
GrGLSLPPFragmentBuilder* fragBuilder = args.fFragBuilder;
// Setup pass through color
if (!gp.colorIgnored()) {
this->setupUniformColor(fragBuilder, uniformHandler, args.fOutputColor, &fColorUniform);
}
// Setup position
this->setupPosition(vertBuilder,
uniformHandler,
gpArgs,
gp.inPosition()->fName,
gp.viewMatrix(),
&fViewMatrixUniform);
// Setup KLM
const char* devkLMMatrixName;
fDevKLMUniform = uniformHandler->addUniform(kVertex_GrShaderFlag, kMat33f_GrSLType,
kHigh_GrSLPrecision, "KLM", &devkLMMatrixName);
GrGLSLVertToFrag v(kVec3f_GrSLType);
varyingHandler->addVarying("CubicCoeffs", &v, kHigh_GrSLPrecision);
vertBuilder->codeAppendf("%s = %s * vec3(%s, 1);",
v.vsOut(), devkLMMatrixName, gpArgs->fPositionVar.c_str());
GrGLSLVertToFrag gradCoeffs(kVec4f_GrSLType);
if (kFillAA_GrProcessorEdgeType == fEdgeType || kHairlineAA_GrProcessorEdgeType == fEdgeType) {
varyingHandler->addVarying("GradCoeffs", &gradCoeffs, kHigh_GrSLPrecision);
vertBuilder->codeAppendf("highp float k = %s[0], l = %s[1], m = %s[2];",
v.vsOut(), v.vsOut(), v.vsOut());
vertBuilder->codeAppendf("highp vec2 gk = vec2(%s[0][0], %s[1][0]), "
"gl = vec2(%s[0][1], %s[1][1]), "
"gm = vec2(%s[0][2], %s[1][2]);",
devkLMMatrixName, devkLMMatrixName, devkLMMatrixName,
devkLMMatrixName, devkLMMatrixName, devkLMMatrixName);
vertBuilder->codeAppendf("%s = vec4(3 * k * gk, -m * gl - l * gm);",
gradCoeffs.vsOut());
}
// emit transforms with position
this->emitTransforms(vertBuilder,
varyingHandler,
uniformHandler,
gpArgs->fPositionVar,
gp.inPosition()->fName,
args.fFPCoordTransformHandler);
GrShaderVar edgeAlpha("edgeAlpha", kFloat_GrSLType, 0, kHigh_GrSLPrecision);
GrShaderVar gF("gF", kVec2f_GrSLType, 0, kHigh_GrSLPrecision);
GrShaderVar func("func", kFloat_GrSLType, 0, kHigh_GrSLPrecision);
fragBuilder->declAppend(edgeAlpha);
fragBuilder->declAppend(gF);
fragBuilder->declAppend(func);
switch (fEdgeType) {
case kHairlineAA_GrProcessorEdgeType: {
fragBuilder->codeAppendf("%s = %s.x * %s.xy + %s.zw;",
gF.c_str(), v.fsIn(), gradCoeffs.fsIn(), gradCoeffs.fsIn());
fragBuilder->codeAppendf("%s = %s.x * %s.x * %s.x - %s.y * %s.z;",
func.c_str(), v.fsIn(), v.fsIn(),
v.fsIn(), v.fsIn(), v.fsIn());
fragBuilder->codeAppendf("%s = abs(%s);", func.c_str(), func.c_str());
fragBuilder->codeAppendf("%s = %s * inversesqrt(dot(%s, %s));",
edgeAlpha.c_str(), func.c_str(), gF.c_str(), gF.c_str());
fragBuilder->codeAppendf("%s = max(1.0 - %s, 0.0);",
edgeAlpha.c_str(), edgeAlpha.c_str());
// Add line below for smooth cubic ramp
// fragBuilder->codeAppendf("%s = %s * %s * (3.0 - 2.0 * %s);",
// edgeAlpha.c_str(), edgeAlpha.c_str(), edgeAlpha.c_str(),
// edgeAlpha.c_str());
break;
}
case kFillAA_GrProcessorEdgeType: {
fragBuilder->codeAppendf("%s = %s.x * %s.xy + %s.zw;",
gF.c_str(), v.fsIn(), gradCoeffs.fsIn(), gradCoeffs.fsIn());
fragBuilder->codeAppendf("%s = %s.x * %s.x * %s.x - %s.y * %s.z;",
func.c_str(),
v.fsIn(), v.fsIn(), v.fsIn(), v.fsIn(), v.fsIn());
fragBuilder->codeAppendf("%s = %s * inversesqrt(dot(%s, %s));",
edgeAlpha.c_str(), func.c_str(), gF.c_str(), gF.c_str());
fragBuilder->codeAppendf("%s = clamp(0.5 - %s, 0.0, 1.0);",
edgeAlpha.c_str(), edgeAlpha.c_str());
// Add line below for smooth cubic ramp
// fragBuilder->codeAppendf("%s = %s * %s * (3.0 - 2.0 * %s);",
// edgeAlpha.c_str(), edgeAlpha.c_str(), edgeAlpha.c_str(),
// edgeAlpha.c_str());
break;
}
case kFillBW_GrProcessorEdgeType: {
fragBuilder->codeAppendf("%s = %s.x * %s.x * %s.x - %s.y * %s.z;",
edgeAlpha.c_str(), v.fsIn(), v.fsIn(),
v.fsIn(), v.fsIn(), v.fsIn());
fragBuilder->codeAppendf("%s = float(%s < 0.0);", edgeAlpha.c_str(), edgeAlpha.c_str());
break;
}
default:
SkFAIL("Shouldn't get here");
}
fragBuilder->codeAppendf("%s = vec4(%s);", args.fOutputCoverage, edgeAlpha.c_str());
}
void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override{
const GrDistanceFieldLCDTextGeoProc& dfTexEffect =
args.fGP.cast<GrDistanceFieldLCDTextGeoProc>();
GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
// emit attributes
varyingHandler->emitAttributes(dfTexEffect);
const char* atlasSizeInvName;
fAtlasSizeInvUniform = uniformHandler->addUniform(kVertex_GrShaderFlag,
kFloat2_GrSLType,
kHigh_GrSLPrecision,
"AtlasSizeInv",
&atlasSizeInvName);
GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
// setup pass through color
varyingHandler->addPassThroughAttribute(dfTexEffect.inColor(), args.fOutputColor);
// Setup position
gpArgs->fPositionVar = dfTexEffect.inPosition()->asShaderVar();
// emit transforms
this->emitTransforms(vertBuilder,
varyingHandler,
uniformHandler,
dfTexEffect.inPosition()->asShaderVar(),
dfTexEffect.localMatrix(),
args.fFPCoordTransformHandler);
// set up varyings
GrGLSLVarying uv(kFloat2_GrSLType);
GrSLType texIdxType = args.fShaderCaps->integerSupport() ? kInt_GrSLType : kFloat_GrSLType;
GrGLSLVarying texIdx(texIdxType);
GrGLSLVarying st(kFloat2_GrSLType);
append_index_uv_varyings(args, dfTexEffect.inTextureCoords()->fName, atlasSizeInvName,
&uv, &texIdx, &st);
GrGLSLVarying delta(kFloat_GrSLType);
varyingHandler->addVarying("Delta", &delta);
if (dfTexEffect.getFlags() & kBGR_DistanceFieldEffectFlag) {
vertBuilder->codeAppendf("%s = -%s.x/3.0;", delta.vsOut(), atlasSizeInvName);
} else {
vertBuilder->codeAppendf("%s = %s.x/3.0;", delta.vsOut(), atlasSizeInvName);
}
// add frag shader code
bool isUniformScale = (dfTexEffect.getFlags() & kUniformScale_DistanceFieldEffectMask) ==
kUniformScale_DistanceFieldEffectMask;
bool isSimilarity = SkToBool(dfTexEffect.getFlags() & kSimilarity_DistanceFieldEffectFlag);
bool isGammaCorrect =
SkToBool(dfTexEffect.getFlags() & kGammaCorrect_DistanceFieldEffectFlag);
// create LCD offset adjusted by inverse of transform
// Use highp to work around aliasing issues
fragBuilder->codeAppendf("float2 uv = %s;\n", uv.fsIn());
if (isUniformScale) {
#ifdef SK_VULKAN
fragBuilder->codeAppendf("half st_grad_len = abs(dFdx(%s.x));", st.fsIn());
#else
// We use the y gradient because there is a bug in the Mali 400 in the x direction.
fragBuilder->codeAppendf("half st_grad_len = abs(dFdy(%s.y));", st.fsIn());
#endif
fragBuilder->codeAppendf("half2 offset = half2(st_grad_len*%s, 0.0);", delta.fsIn());
} else if (isSimilarity) {
// For a similarity matrix with rotation, the gradient will not be aligned
// with the texel coordinate axes, so we need to calculate it.
#ifdef SK_VULKAN
fragBuilder->codeAppendf("half2 st_grad = dFdx(%s);", st.fsIn());
fragBuilder->codeAppendf("half2 offset = %s*st_grad;", delta.fsIn());
#else
// We use dFdy because of a Mali 400 bug, and rotate -90 degrees to
// get the gradient in the x direction.
fragBuilder->codeAppendf("half2 st_grad = dFdy(%s);", st.fsIn());
fragBuilder->codeAppendf("half2 offset = %s*half2(st_grad.y, -st_grad.x);",
delta.fsIn());
#endif
fragBuilder->codeAppend("half st_grad_len = length(st_grad);");
} else {
fragBuilder->codeAppendf("half2 st = %s;\n", st.fsIn());
fragBuilder->codeAppend("half2 Jdx = dFdx(st);");
fragBuilder->codeAppend("half2 Jdy = dFdy(st);");
fragBuilder->codeAppendf("half2 offset = %s*Jdx;", delta.fsIn());
}
// sample the texture by index
fragBuilder->codeAppend("half4 texColor;");
append_multitexture_lookup(args, dfTexEffect.numTextureSamplers(),
texIdx, "uv", "texColor");
// green is distance to uv center
fragBuilder->codeAppend("half3 distance;");
fragBuilder->codeAppend("distance.y = texColor.r;");
// red is distance to left offset
fragBuilder->codeAppend("half2 uv_adjusted = uv - offset;");
append_multitexture_lookup(args, dfTexEffect.numTextureSamplers(),
texIdx, "uv_adjusted", "texColor");
fragBuilder->codeAppend("distance.x = texColor.r;");
// blue is distance to right offset
fragBuilder->codeAppend("uv_adjusted = uv + offset;");
append_multitexture_lookup(args, dfTexEffect.numTextureSamplers(),
texIdx, "uv_adjusted", "texColor");
fragBuilder->codeAppend("distance.z = texColor.r;");
fragBuilder->codeAppend("distance = "
"half3(" SK_DistanceFieldMultiplier ")*(distance - half3(" SK_DistanceFieldThreshold"));");
// adjust width based on gamma
const char* distanceAdjustUniName = nullptr;
fDistanceAdjustUni = uniformHandler->addUniform(kFragment_GrShaderFlag, kHalf3_GrSLType,
"DistanceAdjust", &distanceAdjustUniName);
fragBuilder->codeAppendf("distance -= %s;", distanceAdjustUniName);
// To be strictly correct, we should compute the anti-aliasing factor separately
// for each color component. However, this is only important when using perspective
// transformations, and even then using a single factor seems like a reasonable
// trade-off between quality and speed.
fragBuilder->codeAppend("half afwidth;");
if (isSimilarity) {
// For similarity transform (uniform scale-only is a subset of this), we adjust for the
// effect of the transformation on the distance by using the length of the gradient of
// the texture coordinates. We use st coordinates to ensure we're mapping 1:1 from texel
// space to pixel space.
// this gives us a smooth step across approximately one fragment
fragBuilder->codeAppend("afwidth = " SK_DistanceFieldAAFactor "*st_grad_len;");
} else {
// For general transforms, to determine the amount of correction we multiply a unit
// vector pointing along the SDF gradient direction by the Jacobian of the st coords
// (which is the inverse transform for this fragment) and take the length of the result.
fragBuilder->codeAppend("half2 dist_grad = half2(dFdx(distance.r), dFdy(distance.r));");
// the length of the gradient may be 0, so we need to check for this
// this also compensates for the Adreno, which likes to drop tiles on division by 0
fragBuilder->codeAppend("half dg_len2 = dot(dist_grad, dist_grad);");
fragBuilder->codeAppend("if (dg_len2 < 0.0001) {");
fragBuilder->codeAppend("dist_grad = half2(0.7071, 0.7071);");
fragBuilder->codeAppend("} else {");
fragBuilder->codeAppend("dist_grad = dist_grad*inversesqrt(dg_len2);");
fragBuilder->codeAppend("}");
fragBuilder->codeAppend("half2 grad = half2(dist_grad.x*Jdx.x + dist_grad.y*Jdy.x,");
fragBuilder->codeAppend(" dist_grad.x*Jdx.y + dist_grad.y*Jdy.y);");
// this gives us a smooth step across approximately one fragment
fragBuilder->codeAppend("afwidth = " SK_DistanceFieldAAFactor "*length(grad);");
}
// The smoothstep falloff compensates for the non-linear sRGB response curve. If we are
// doing gamma-correct rendering (to an sRGB or F16 buffer), then we actually want distance
// mapped linearly to coverage, so use a linear step:
if (isGammaCorrect) {
fragBuilder->codeAppendf("%s = "
"half4(clamp((distance + half3(afwidth)) / half3(2.0 * afwidth), 0.0, 1.0), 1.0);",
args.fOutputCoverage);
} else {
fragBuilder->codeAppendf(
"%s = half4(smoothstep(half3(-afwidth), half3(afwidth), distance), 1.0);",
args.fOutputCoverage);
}
}
void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override {
const auto& proc = args.fGP.cast<Processor>();
bool useHWDerivatives = (proc.fFlags & Flags::kUseHWDerivatives);
bool hasPerspective = (proc.fFlags & Flags::kHasPerspective);
bool hasLocalCoords = (proc.fFlags & Flags::kHasLocalCoords);
SkASSERT(useHWDerivatives == hasPerspective);
SkASSERT(proc.vertexStride() == sizeof(MSAAVertex));
// Emit the vertex shader.
GrGLSLVertexBuilder* v = args.fVertBuilder;
GrGLSLVaryingHandler* varyings = args.fVaryingHandler;
varyings->emitAttributes(proc);
varyings->addPassThroughAttribute(*proc.fColorAttrib, args.fOutputColor,
GrGLSLVaryingHandler::Interpolation::kCanBeFlat);
// Unpack vertex attribs.
v->codeAppendf("float2 corner = corner_and_radius_outsets.xy;");
v->codeAppendf("float2 radius_outset = corner_and_radius_outsets.zw;");
// Identify our radii.
v->codeAppend("float2 radii;");
v->codeAppend("radii.x = dot(radii_selector, radii_x);");
v->codeAppend("radii.y = dot(radii_selector, radii_y);");
v->codeAppendf("bool is_arc_section = (radii.x > 0);");
v->codeAppendf("radii = abs(radii);");
// Find our vertex position, adjusted for radii. Our rect is drawn in normalized
// [-1,-1,+1,+1] space.
v->codeAppend("float2 vertexpos = corner + radius_outset * radii;");
// Emit transforms.
GrShaderVar localCoord("", kFloat2_GrSLType);
if (hasLocalCoords) {
v->codeAppend("float2 localcoord = (local_rect.xy * (1 - vertexpos) + "
"local_rect.zw * (1 + vertexpos)) * .5;");
localCoord.set(kFloat2_GrSLType, "localcoord");
}
this->emitTransforms(v, varyings, args.fUniformHandler, localCoord,
args.fFPCoordTransformHandler);
// Transform to device space.
if (!hasPerspective) {
v->codeAppend("float2x2 skewmatrix = float2x2(skew.xy, skew.zw);");
v->codeAppend("float2 devcoord = vertexpos * skewmatrix + translate;");
gpArgs->fPositionVar.set(kFloat2_GrSLType, "devcoord");
} else {
v->codeAppend("float3x3 persp_matrix = float3x3(persp_x, persp_y, persp_z);");
v->codeAppend("float3 devcoord = float3(vertexpos, 1) * persp_matrix;");
gpArgs->fPositionVar.set(kFloat3_GrSLType, "devcoord");
}
// Determine normalized arc coordinates for the implicit function.
GrGLSLVarying arcCoord((useHWDerivatives) ? kFloat2_GrSLType : kFloat4_GrSLType);
varyings->addVarying("arccoord", &arcCoord);
v->codeAppendf("if (is_arc_section) {");
v->codeAppendf( "%s.xy = 1 - abs(radius_outset);", arcCoord.vsOut());
if (!useHWDerivatives) {
// The gradient is order-1: Interpolate it across arccoord.zw.
// This doesn't work with perspective.
SkASSERT(!hasPerspective);
v->codeAppendf("float2x2 derivatives = inverse(skewmatrix);");
v->codeAppendf("%s.zw = derivatives * (%s.xy/radii * corner * 2);",
arcCoord.vsOut(), arcCoord.vsOut());
}
v->codeAppendf("} else {");
if (useHWDerivatives) {
v->codeAppendf("%s = float2(0);", arcCoord.vsOut());
} else {
v->codeAppendf("%s = float4(0);", arcCoord.vsOut());
}
v->codeAppendf("}");
// Emit the fragment shader.
GrGLSLFPFragmentBuilder* f = args.fFragBuilder;
f->codeAppendf("%s = half4(1);", args.fOutputCoverage);
// If x,y == 0, then we are drawing a triangle that does not track an arc.
f->codeAppendf("if (float2(0) != %s.xy) {", arcCoord.fsIn());
f->codeAppendf( "float fn = dot(%s.xy, %s.xy) - 1;", arcCoord.fsIn(), arcCoord.fsIn());
if (GrAAType::kMSAA == proc.fAAType) {
using ScopeFlags = GrGLSLFPFragmentBuilder::ScopeFlags;
if (!useHWDerivatives) {
f->codeAppendf("float2 grad = %s.zw;", arcCoord.fsIn());
f->applyFnToMultisampleMask("fn", "grad", ScopeFlags::kInsidePerPrimitiveBranch);
} else {
f->applyFnToMultisampleMask("fn", nullptr, ScopeFlags::kInsidePerPrimitiveBranch);
}
} else {
f->codeAppendf("if (fn > 0) {");
f->codeAppendf( "%s = half4(0);", args.fOutputCoverage);
f->codeAppendf("}");
}
f->codeAppendf("}");
}
void GrGLCubicEffect::onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) {
GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
const GrCubicEffect& gp = args.fGP.cast<GrCubicEffect>();
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
// emit attributes
varyingHandler->emitAttributes(gp);
GrGLSLVertToFrag v(kVec4f_GrSLType);
varyingHandler->addVarying("CubicCoeffs", &v, kHigh_GrSLPrecision);
vertBuilder->codeAppendf("%s = %s;", v.vsOut(), gp.inCubicCoeffs()->fName);
GrGLSLPPFragmentBuilder* fragBuilder = args.fFragBuilder;
// Setup pass through color
if (!gp.colorIgnored()) {
this->setupUniformColor(fragBuilder, uniformHandler, args.fOutputColor, &fColorUniform);
}
// Setup position
this->setupPosition(vertBuilder,
uniformHandler,
gpArgs,
gp.inPosition()->fName,
gp.viewMatrix(),
&fViewMatrixUniform);
// emit transforms with position
this->emitTransforms(vertBuilder,
varyingHandler,
uniformHandler,
gpArgs->fPositionVar,
gp.inPosition()->fName,
args.fFPCoordTransformHandler);
GrShaderVar edgeAlpha("edgeAlpha", kFloat_GrSLType, 0, kHigh_GrSLPrecision);
GrShaderVar dklmdx("dklmdx", kVec3f_GrSLType, 0, kHigh_GrSLPrecision);
GrShaderVar dklmdy("dklmdy", kVec3f_GrSLType, 0, kHigh_GrSLPrecision);
GrShaderVar dfdx("dfdx", kFloat_GrSLType, 0, kHigh_GrSLPrecision);
GrShaderVar dfdy("dfdy", kFloat_GrSLType, 0, kHigh_GrSLPrecision);
GrShaderVar gF("gF", kVec2f_GrSLType, 0, kHigh_GrSLPrecision);
GrShaderVar gFM("gFM", kFloat_GrSLType, 0, kHigh_GrSLPrecision);
GrShaderVar func("func", kFloat_GrSLType, 0, kHigh_GrSLPrecision);
fragBuilder->declAppend(edgeAlpha);
fragBuilder->declAppend(dklmdx);
fragBuilder->declAppend(dklmdy);
fragBuilder->declAppend(dfdx);
fragBuilder->declAppend(dfdy);
fragBuilder->declAppend(gF);
fragBuilder->declAppend(gFM);
fragBuilder->declAppend(func);
switch (fEdgeType) {
case kHairlineAA_GrProcessorEdgeType: {
fragBuilder->codeAppendf("%s = dFdx(%s.xyz);", dklmdx.c_str(), v.fsIn());
fragBuilder->codeAppendf("%s = dFdy(%s.xyz);", dklmdy.c_str(), v.fsIn());
fragBuilder->codeAppendf("%s = 3.0 * %s.x * %s.x * %s.x - %s.y * %s.z - %s.z * %s.y;",
dfdx.c_str(), v.fsIn(), v.fsIn(), dklmdx.c_str(), v.fsIn(),
dklmdx.c_str(), v.fsIn(), dklmdx.c_str());
fragBuilder->codeAppendf("%s = 3.0 * %s.x * %s.x * %s.x - %s.y * %s.z - %s.z * %s.y;",
dfdy.c_str(), v.fsIn(), v.fsIn(), dklmdy.c_str(), v.fsIn(),
dklmdy.c_str(), v.fsIn(), dklmdy.c_str());
fragBuilder->codeAppendf("%s = vec2(%s, %s);", gF.c_str(), dfdx.c_str(), dfdy.c_str());
fragBuilder->codeAppendf("%s = sqrt(dot(%s, %s));",
gFM.c_str(), gF.c_str(), gF.c_str());
fragBuilder->codeAppendf("%s = %s.x * %s.x * %s.x - %s.y * %s.z;",
func.c_str(), v.fsIn(), v.fsIn(),
v.fsIn(), v.fsIn(), v.fsIn());
fragBuilder->codeAppendf("%s = abs(%s);", func.c_str(), func.c_str());
fragBuilder->codeAppendf("%s = %s / %s;",
edgeAlpha.c_str(), func.c_str(), gFM.c_str());
fragBuilder->codeAppendf("%s = max(1.0 - %s, 0.0);",
edgeAlpha.c_str(), edgeAlpha.c_str());
// Add line below for smooth cubic ramp
// fragBuilder->codeAppendf("%s = %s * %s * (3.0 - 2.0 * %s);",
// edgeAlpha.c_str(), edgeAlpha.c_str(), edgeAlpha.c_str(),
// edgeAlpha.c_str());
break;
}
case kFillAA_GrProcessorEdgeType: {
fragBuilder->codeAppendf("%s = dFdx(%s.xyz);", dklmdx.c_str(), v.fsIn());
fragBuilder->codeAppendf("%s = dFdy(%s.xyz);", dklmdy.c_str(), v.fsIn());
fragBuilder->codeAppendf("%s ="
"3.0 * %s.x * %s.x * %s.x - %s.y * %s.z - %s.z * %s.y;",
dfdx.c_str(), v.fsIn(), v.fsIn(), dklmdx.c_str(), v.fsIn(),
dklmdx.c_str(), v.fsIn(), dklmdx.c_str());
fragBuilder->codeAppendf("%s = 3.0 * %s.x * %s.x * %s.x - %s.y * %s.z - %s.z * %s.y;",
dfdy.c_str(), v.fsIn(), v.fsIn(), dklmdy.c_str(), v.fsIn(),
dklmdy.c_str(), v.fsIn(), dklmdy.c_str());
fragBuilder->codeAppendf("%s = vec2(%s, %s);", gF.c_str(), dfdx.c_str(), dfdy.c_str());
fragBuilder->codeAppendf("%s = sqrt(dot(%s, %s));",
gFM.c_str(), gF.c_str(), gF.c_str());
fragBuilder->codeAppendf("%s = %s.x * %s.x * %s.x - %s.y * %s.z;",
func.c_str(),
v.fsIn(), v.fsIn(), v.fsIn(), v.fsIn(), v.fsIn());
fragBuilder->codeAppendf("%s = %s / %s;",
edgeAlpha.c_str(), func.c_str(), gFM.c_str());
fragBuilder->codeAppendf("%s = clamp(0.5 - %s, 0.0, 1.0);",
edgeAlpha.c_str(), edgeAlpha.c_str());
// Add line below for smooth cubic ramp
// fragBuilder->codeAppendf("%s = %s * %s * (3.0 - 2.0 * %s);",
// edgeAlpha.c_str(), edgeAlpha.c_str(), edgeAlpha.c_str(),
// edgeAlpha.c_str());
break;
}
case kFillBW_GrProcessorEdgeType: {
fragBuilder->codeAppendf("%s = %s.x * %s.x * %s.x - %s.y * %s.z;",
edgeAlpha.c_str(), v.fsIn(), v.fsIn(),
v.fsIn(), v.fsIn(), v.fsIn());
fragBuilder->codeAppendf("%s = float(%s < 0.0);", edgeAlpha.c_str(), edgeAlpha.c_str());
break;
}
default:
SkFAIL("Shouldn't get here");
}
fragBuilder->codeAppendf("%s = vec4(%s);", args.fOutputCoverage, edgeAlpha.c_str());
}
void GrGLConicEffect::onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) {
GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
const GrConicEffect& gp = args.fGP.cast<GrConicEffect>();
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
// emit attributes
varyingHandler->emitAttributes(gp);
GrGLSLVertToFrag v(kVec4f_GrSLType);
varyingHandler->addVarying("ConicCoeffs", &v, kHigh_GrSLPrecision);
vertBuilder->codeAppendf("%s = %s;", v.vsOut(), gp.inConicCoeffs()->fName);
GrGLSLPPFragmentBuilder* fragBuilder = args.fFragBuilder;
// Setup pass through color
this->setupUniformColor(fragBuilder, uniformHandler, args.fOutputColor, &fColorUniform);
// Setup position
this->setupPosition(vertBuilder,
uniformHandler,
gpArgs,
gp.inPosition()->fName,
gp.viewMatrix(),
&fViewMatrixUniform);
// emit transforms with position
this->emitTransforms(vertBuilder,
varyingHandler,
uniformHandler,
gpArgs->fPositionVar,
gp.inPosition()->fName,
gp.localMatrix(),
args.fFPCoordTransformHandler);
// TODO: this precision check should actually be a check on the number of bits
// high and medium provide and the selection of the lowest level that suffices.
// Additionally we should assert that the upstream code only lets us get here if
// either high or medium provides the required number of bits.
GrSLPrecision precision = kHigh_GrSLPrecision;
const GrShaderCaps::PrecisionInfo& highP = args.fShaderCaps->getFloatShaderPrecisionInfo(
kFragment_GrShaderType,
kHigh_GrSLPrecision);
if (!highP.supported()) {
precision = kMedium_GrSLPrecision;
}
GrShaderVar edgeAlpha("edgeAlpha", kFloat_GrSLType, 0, precision);
GrShaderVar dklmdx("dklmdx", kVec3f_GrSLType, 0, precision);
GrShaderVar dklmdy("dklmdy", kVec3f_GrSLType, 0, precision);
GrShaderVar dfdx("dfdx", kFloat_GrSLType, 0, precision);
GrShaderVar dfdy("dfdy", kFloat_GrSLType, 0, precision);
GrShaderVar gF("gF", kVec2f_GrSLType, 0, precision);
GrShaderVar gFM("gFM", kFloat_GrSLType, 0, precision);
GrShaderVar func("func", kFloat_GrSLType, 0, precision);
fragBuilder->declAppend(edgeAlpha);
fragBuilder->declAppend(dklmdx);
fragBuilder->declAppend(dklmdy);
fragBuilder->declAppend(dfdx);
fragBuilder->declAppend(dfdy);
fragBuilder->declAppend(gF);
fragBuilder->declAppend(gFM);
fragBuilder->declAppend(func);
switch (fEdgeType) {
case kHairlineAA_GrProcessorEdgeType: {
fragBuilder->codeAppendf("%s = dFdx(%s.xyz);", dklmdx.c_str(), v.fsIn());
fragBuilder->codeAppendf("%s = dFdy(%s.xyz);", dklmdy.c_str(), v.fsIn());
fragBuilder->codeAppendf("%s = 2.0 * %s.x * %s.x - %s.y * %s.z - %s.z * %s.y;",
dfdx.c_str(),
v.fsIn(), dklmdx.c_str(),
v.fsIn(), dklmdx.c_str(),
v.fsIn(), dklmdx.c_str());
fragBuilder->codeAppendf("%s = 2.0 * %s.x * %s.x - %s.y * %s.z - %s.z * %s.y;",
dfdy.c_str(),
v.fsIn(), dklmdy.c_str(),
v.fsIn(), dklmdy.c_str(),
v.fsIn(), dklmdy.c_str());
fragBuilder->codeAppendf("%s = vec2(%s, %s);", gF.c_str(), dfdx.c_str(), dfdy.c_str());
fragBuilder->codeAppendf("%s = sqrt(dot(%s, %s));",
gFM.c_str(), gF.c_str(), gF.c_str());
fragBuilder->codeAppendf("%s = %s.x*%s.x - %s.y*%s.z;",
func.c_str(), v.fsIn(), v.fsIn(), v.fsIn(), v.fsIn());
fragBuilder->codeAppendf("%s = abs(%s);", func.c_str(), func.c_str());
fragBuilder->codeAppendf("%s = %s / %s;",
edgeAlpha.c_str(), func.c_str(), gFM.c_str());
fragBuilder->codeAppendf("%s = max(1.0 - %s, 0.0);",
edgeAlpha.c_str(), edgeAlpha.c_str());
// Add line below for smooth cubic ramp
// fragBuilder->codeAppend("edgeAlpha = edgeAlpha*edgeAlpha*(3.0-2.0*edgeAlpha);");
break;
}
case kFillAA_GrProcessorEdgeType: {
fragBuilder->codeAppendf("%s = dFdx(%s.xyz);", dklmdx.c_str(), v.fsIn());
fragBuilder->codeAppendf("%s = dFdy(%s.xyz);", dklmdy.c_str(), v.fsIn());
fragBuilder->codeAppendf("%s ="
"2.0 * %s.x * %s.x - %s.y * %s.z - %s.z * %s.y;",
dfdx.c_str(),
v.fsIn(), dklmdx.c_str(),
v.fsIn(), dklmdx.c_str(),
v.fsIn(), dklmdx.c_str());
fragBuilder->codeAppendf("%s ="
"2.0 * %s.x * %s.x - %s.y * %s.z - %s.z * %s.y;",
dfdy.c_str(),
v.fsIn(), dklmdy.c_str(),
v.fsIn(), dklmdy.c_str(),
v.fsIn(), dklmdy.c_str());
fragBuilder->codeAppendf("%s = vec2(%s, %s);", gF.c_str(), dfdx.c_str(), dfdy.c_str());
fragBuilder->codeAppendf("%s = sqrt(dot(%s, %s));",
gFM.c_str(), gF.c_str(), gF.c_str());
fragBuilder->codeAppendf("%s = %s.x * %s.x - %s.y * %s.z;",
func.c_str(), v.fsIn(), v.fsIn(), v.fsIn(), v.fsIn());
fragBuilder->codeAppendf("%s = %s / %s;",
edgeAlpha.c_str(), func.c_str(), gFM.c_str());
fragBuilder->codeAppendf("%s = clamp(0.5 - %s, 0.0, 1.0);",
edgeAlpha.c_str(), edgeAlpha.c_str());
// Add line below for smooth cubic ramp
// fragBuilder->codeAppend("edgeAlpha = edgeAlpha*edgeAlpha*(3.0-2.0*edgeAlpha);");
break;
}
case kFillBW_GrProcessorEdgeType: {
fragBuilder->codeAppendf("%s = %s.x * %s.x - %s.y * %s.z;",
edgeAlpha.c_str(), v.fsIn(), v.fsIn(), v.fsIn(), v.fsIn());
fragBuilder->codeAppendf("%s = float(%s < 0.0);",
edgeAlpha.c_str(), edgeAlpha.c_str());
break;
}
default:
SkFAIL("Shouldn't get here");
}
// TODO should we really be doing this?
if (gp.coverageScale() != 0xff) {
const char* coverageScale;
fCoverageScaleUniform = uniformHandler->addUniform(kFragment_GrShaderFlag,
kFloat_GrSLType,
kHigh_GrSLPrecision,
"Coverage",
&coverageScale);
fragBuilder->codeAppendf("%s = vec4(%s * %s);",
args.fOutputCoverage, coverageScale, edgeAlpha.c_str());
} else {
fragBuilder->codeAppendf("%s = vec4(%s);", args.fOutputCoverage, edgeAlpha.c_str());
}
}
void GLSLPathProcessor::onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) {
using InstanceAttribs = GrCCPRPathProcessor::InstanceAttribs;
const GrCCPRPathProcessor& proc = args.fGP.cast<GrCCPRPathProcessor>();
GrGLSLUniformHandler* uniHandler = args.fUniformHandler;
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
const char* atlasAdjust;
fAtlasAdjustUniform = uniHandler->addUniform(
kVertex_GrShaderFlag,
kVec2f_GrSLType, kHigh_GrSLPrecision, "atlas_adjust", &atlasAdjust);
varyingHandler->emitAttributes(proc);
GrGLSLVertToFrag texcoord(kVec2f_GrSLType);
GrGLSLVertToFrag color(kVec4f_GrSLType);
varyingHandler->addVarying("texcoord", &texcoord, kHigh_GrSLPrecision);
varyingHandler->addFlatPassThroughAttribute(&proc.getInstanceAttrib(InstanceAttribs::kColor),
args.fOutputColor, kLow_GrSLPrecision);
// Vertex shader.
GrGLSLVertexBuilder* v = args.fVertBuilder;
// Find the intersections of (bloated) devBounds and devBounds45 in order to come up with an
// octagon that circumscribes the (bloated) path. A vertex is the intersection of two lines:
// one edge from the path's bounding box and one edge from its 45-degree bounding box.
v->codeAppendf("highp mat2 N = mat2(%s);", proc.getEdgeNormsAttrib().fName);
// N[0] is the normal for the edge we are intersecting from the regular bounding box, pointing
// out of the octagon.
v->codeAppendf("highp vec2 refpt = (min(N[0].x, N[0].y) < 0) ? %s.xy : %s.zw;",
proc.getInstanceAttrib(InstanceAttribs::kDevBounds).fName,
proc.getInstanceAttrib(InstanceAttribs::kDevBounds).fName);
v->codeAppendf("refpt += N[0] * %f;", kAABloatRadius); // bloat for AA.
// N[1] is the normal for the edge we are intersecting from the 45-degree bounding box, pointing
// out of the octagon.
v->codeAppendf("highp vec2 refpt45 = (N[1].x < 0) ? %s.xy : %s.zw;",
proc.getInstanceAttrib(InstanceAttribs::kDevBounds45).fName,
proc.getInstanceAttrib(InstanceAttribs::kDevBounds45).fName);
v->codeAppendf("refpt45 *= mat2(.5,.5,-.5,.5);"); // transform back to device space.
v->codeAppendf("refpt45 += N[1] * %f;", kAABloatRadius); // bloat for AA.
v->codeAppend ("highp vec2 K = vec2(dot(N[0], refpt), dot(N[1], refpt45));");
v->codeAppendf("highp vec2 octocoord = K * inverse(N);");
gpArgs->fPositionVar.set(kVec2f_GrSLType, "octocoord");
// Convert to atlas coordinates in order to do our texture lookup.
v->codeAppendf("highp vec2 atlascoord = octocoord + vec2(%s);",
proc.getInstanceAttrib(InstanceAttribs::kAtlasOffset).fName);
if (kTopLeft_GrSurfaceOrigin == proc.atlas()->origin()) {
v->codeAppendf("%s = atlascoord * %s;", texcoord.vsOut(), atlasAdjust);
} else {
SkASSERT(kBottomLeft_GrSurfaceOrigin == proc.atlas()->origin());
v->codeAppendf("%s = vec2(atlascoord.x * %s.x, 1 - atlascoord.y * %s.y);",
texcoord.vsOut(), atlasAdjust, atlasAdjust);
}
// Convert to (local) path cordinates.
v->codeAppendf("highp vec2 pathcoord = inverse(mat2(%s)) * (octocoord - %s);",
proc.getInstanceAttrib(InstanceAttribs::kViewMatrix).fName,
proc.getInstanceAttrib(InstanceAttribs::kViewTranslate).fName);
this->emitTransforms(v, varyingHandler, uniHandler, gpArgs->fPositionVar, "pathcoord",
args.fFPCoordTransformHandler);
// Fragment shader.
GrGLSLPPFragmentBuilder* f = args.fFragBuilder;
f->codeAppend ("mediump float coverage_count = ");
f->appendTextureLookup(args.fTexSamplers[0], texcoord.fsIn(), kVec2f_GrSLType);
f->codeAppend (".a;");
if (SkPath::kWinding_FillType == proc.fillType()) {
f->codeAppendf("%s = vec4(min(abs(coverage_count), 1));", args.fOutputCoverage);
} else {
SkASSERT(SkPath::kEvenOdd_FillType == proc.fillType());
f->codeAppend ("mediump float t = mod(abs(coverage_count), 2);");
f->codeAppendf("%s = vec4(1 - abs(t - 1));", args.fOutputCoverage);
}
}
void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override{
const GrDistanceFieldLCDTextGeoProc& dfTexEffect =
args.fGP.cast<GrDistanceFieldLCDTextGeoProc>();
GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
// emit attributes
varyingHandler->emitAttributes(dfTexEffect);
GrGLSLPPFragmentBuilder* fragBuilder = args.fFragBuilder;
// setup pass through color
if (!dfTexEffect.colorIgnored()) {
varyingHandler->addPassThroughAttribute(dfTexEffect.inColor(), args.fOutputColor);
}
// Setup position
this->setupPosition(vertBuilder,
uniformHandler,
gpArgs,
dfTexEffect.inPosition()->fName,
dfTexEffect.viewMatrix(),
&fViewMatrixUniform);
// emit transforms
this->emitTransforms(vertBuilder,
varyingHandler,
uniformHandler,
gpArgs->fPositionVar,
dfTexEffect.inPosition()->fName,
args.fTransformsIn,
args.fTransformsOut);
// set up varyings
bool isUniformScale = (dfTexEffect.getFlags() & kUniformScale_DistanceFieldEffectMask) ==
kUniformScale_DistanceFieldEffectMask;
bool isSimilarity = SkToBool(dfTexEffect.getFlags() & kSimilarity_DistanceFieldEffectFlag);
GrGLSLVertToFrag recipScale(kFloat_GrSLType);
GrGLSLVertToFrag uv(kVec2f_GrSLType);
varyingHandler->addVarying("TextureCoords", &uv, kHigh_GrSLPrecision);
vertBuilder->codeAppendf("%s = %s;", uv.vsOut(), dfTexEffect.inTextureCoords()->fName);
// compute numbers to be hardcoded to convert texture coordinates from float to int
SkASSERT(dfTexEffect.numTextures() == 1);
GrTexture* atlas = dfTexEffect.textureAccess(0).getTexture();
SkASSERT(atlas && SkIsPow2(atlas->width()) && SkIsPow2(atlas->height()));
GrGLSLVertToFrag st(kVec2f_GrSLType);
varyingHandler->addVarying("IntTextureCoords", &st, kHigh_GrSLPrecision);
vertBuilder->codeAppendf("%s = vec2(%d, %d) * %s;", st.vsOut(),
atlas->width(), atlas->height(),
dfTexEffect.inTextureCoords()->fName);
// add frag shader code
SkAssertResult(fragBuilder->enableFeature(
GrGLSLFragmentShaderBuilder::kStandardDerivatives_GLSLFeature));
// create LCD offset adjusted by inverse of transform
// Use highp to work around aliasing issues
fragBuilder->codeAppend(GrGLSLShaderVar::PrecisionString(args.fGLSLCaps,
kHigh_GrSLPrecision));
fragBuilder->codeAppendf("vec2 uv = %s;\n", uv.fsIn());
fragBuilder->codeAppend(GrGLSLShaderVar::PrecisionString(args.fGLSLCaps,
kHigh_GrSLPrecision));
SkScalar lcdDelta = 1.0f / (3.0f * atlas->width());
if (dfTexEffect.getFlags() & kBGR_DistanceFieldEffectFlag) {
fragBuilder->codeAppendf("float delta = -%.*f;\n", SK_FLT_DECIMAL_DIG, lcdDelta);
} else {
fragBuilder->codeAppendf("float delta = %.*f;\n", SK_FLT_DECIMAL_DIG, lcdDelta);
}
if (isUniformScale) {
fragBuilder->codeAppendf("float st_grad_len = abs(dFdy(%s.y));", st.fsIn());
fragBuilder->codeAppend("vec2 offset = vec2(st_grad_len*delta, 0.0);");
} else if (isSimilarity) {
// For a similarity matrix with rotation, the gradient will not be aligned
// with the texel coordinate axes, so we need to calculate it.
// We use dFdy because of a Mali 400 bug, and rotate -90 degrees to
// get the gradient in the x direction.
fragBuilder->codeAppendf("vec2 st_grad = dFdy(%s);", st.fsIn());
fragBuilder->codeAppend("float st_grad_len = length(st_grad);");
fragBuilder->codeAppend("vec2 offset = delta*vec2(st_grad.y, -st_grad.x);");
} else {
fragBuilder->codeAppendf("vec2 st = %s;\n", st.fsIn());
fragBuilder->codeAppend("vec2 Jdx = dFdx(st);");
fragBuilder->codeAppend("vec2 Jdy = dFdy(st);");
fragBuilder->codeAppend("vec2 offset = delta*Jdx;");
}
// green is distance to uv center
fragBuilder->codeAppend("\tvec4 texColor = ");
fragBuilder->appendTextureLookup(args.fSamplers[0], "uv", kVec2f_GrSLType);
fragBuilder->codeAppend(";\n");
fragBuilder->codeAppend("\tvec3 distance;\n");
fragBuilder->codeAppend("\tdistance.y = texColor.r;\n");
// red is distance to left offset
fragBuilder->codeAppend("\tvec2 uv_adjusted = uv - offset;\n");
fragBuilder->codeAppend("\ttexColor = ");
fragBuilder->appendTextureLookup(args.fSamplers[0], "uv_adjusted", kVec2f_GrSLType);
fragBuilder->codeAppend(";\n");
fragBuilder->codeAppend("\tdistance.x = texColor.r;\n");
// blue is distance to right offset
fragBuilder->codeAppend("\tuv_adjusted = uv + offset;\n");
fragBuilder->codeAppend("\ttexColor = ");
fragBuilder->appendTextureLookup(args.fSamplers[0], "uv_adjusted", kVec2f_GrSLType);
fragBuilder->codeAppend(";\n");
fragBuilder->codeAppend("\tdistance.z = texColor.r;\n");
fragBuilder->codeAppend("\tdistance = "
"vec3(" SK_DistanceFieldMultiplier ")*(distance - vec3(" SK_DistanceFieldThreshold"));");
// adjust width based on gamma
const char* distanceAdjustUniName = nullptr;
fDistanceAdjustUni = uniformHandler->addUniform(kFragment_GrShaderFlag,
kVec3f_GrSLType, kDefault_GrSLPrecision,
"DistanceAdjust", &distanceAdjustUniName);
fragBuilder->codeAppendf("distance -= %s;", distanceAdjustUniName);
// To be strictly correct, we should compute the anti-aliasing factor separately
// for each color component. However, this is only important when using perspective
// transformations, and even then using a single factor seems like a reasonable
// trade-off between quality and speed.
fragBuilder->codeAppend("float afwidth;");
if (isSimilarity) {
// For similarity transform (uniform scale-only is a subset of this), we adjust for the
// effect of the transformation on the distance by using the length of the gradient of
// the texture coordinates. We use st coordinates to ensure we're mapping 1:1 from texel
// space to pixel space.
// this gives us a smooth step across approximately one fragment
fragBuilder->codeAppend("afwidth = " SK_DistanceFieldAAFactor "*st_grad_len;");
} else {
// For general transforms, to determine the amount of correction we multiply a unit
// vector pointing along the SDF gradient direction by the Jacobian of the st coords
// (which is the inverse transform for this fragment) and take the length of the result.
fragBuilder->codeAppend("vec2 dist_grad = vec2(dFdx(distance.r), dFdy(distance.r));");
// the length of the gradient may be 0, so we need to check for this
// this also compensates for the Adreno, which likes to drop tiles on division by 0
fragBuilder->codeAppend("float dg_len2 = dot(dist_grad, dist_grad);");
fragBuilder->codeAppend("if (dg_len2 < 0.0001) {");
fragBuilder->codeAppend("dist_grad = vec2(0.7071, 0.7071);");
fragBuilder->codeAppend("} else {");
fragBuilder->codeAppend("dist_grad = dist_grad*inversesqrt(dg_len2);");
fragBuilder->codeAppend("}");
fragBuilder->codeAppend("vec2 grad = vec2(dist_grad.x*Jdx.x + dist_grad.y*Jdy.x,");
fragBuilder->codeAppend(" dist_grad.x*Jdx.y + dist_grad.y*Jdy.y);");
// this gives us a smooth step across approximately one fragment
fragBuilder->codeAppend("afwidth = " SK_DistanceFieldAAFactor "*length(grad);");
}
fragBuilder->codeAppend(
"vec4 val = vec4(smoothstep(vec3(-afwidth), vec3(afwidth), distance), 1.0);");
// set alpha to be max of rgb coverage
fragBuilder->codeAppend("val.a = max(max(val.r, val.g), val.b);");
fragBuilder->codeAppendf("%s = val;", args.fOutputCoverage);
}
void onEmitCode(EmitArgs& args, GrGPArgs* gpArgs) override {
const GrBitmapTextGeoProc& cte = args.fGP.cast<GrBitmapTextGeoProc>();
GrGLSLVertexBuilder* vertBuilder = args.fVertBuilder;
GrGLSLVaryingHandler* varyingHandler = args.fVaryingHandler;
GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
// emit attributes
varyingHandler->emitAttributes(cte);
// compute numbers to be hardcoded to convert texture coordinates from int to float
SkASSERT(cte.numTextures() == 1);
SkDEBUGCODE(GrTexture* atlas = cte.textureAccess(0).getTexture());
SkASSERT(atlas && SkIsPow2(atlas->width()) && SkIsPow2(atlas->height()));
GrGLSLVertToFrag v(kVec2f_GrSLType);
varyingHandler->addVarying("TextureCoords", &v, kHigh_GrSLPrecision);
vertBuilder->codeAppendf("%s = %s;", v.vsOut(),
cte.inTextureCoords()->fName);
GrGLSLPPFragmentBuilder* fragBuilder = args.fFragBuilder;
// Setup pass through color
if (!cte.colorIgnored()) {
if (cte.hasVertexColor()) {
varyingHandler->addPassThroughAttribute(cte.inColor(), args.fOutputColor);
} else {
this->setupUniformColor(fragBuilder, uniformHandler, args.fOutputColor,
&fColorUniform);
}
}
// Setup position
this->setupPosition(vertBuilder, gpArgs, cte.inPosition()->fName);
// emit transforms
this->emitTransforms(vertBuilder,
varyingHandler,
uniformHandler,
gpArgs->fPositionVar,
cte.inPosition()->fName,
cte.localMatrix(),
args.fTransformsIn,
args.fTransformsOut);
if (cte.maskFormat() == kARGB_GrMaskFormat) {
fragBuilder->codeAppendf("%s = ", args.fOutputColor);
fragBuilder->appendTextureLookupAndModulate(args.fOutputColor,
args.fTexSamplers[0],
v.fsIn(),
kVec2f_GrSLType);
fragBuilder->codeAppend(";");
fragBuilder->codeAppendf("%s = vec4(1);", args.fOutputCoverage);
} else {
fragBuilder->codeAppendf("%s = ", args.fOutputCoverage);
fragBuilder->appendTextureLookup(args.fTexSamplers[0], v.fsIn(), kVec2f_GrSLType);
fragBuilder->codeAppend(";");
if (cte.maskFormat() == kA565_GrMaskFormat) {
// set alpha to be max of rgb coverage
fragBuilder->codeAppendf("%s.a = max(max(%s.r, %s.g), %s.b);",
args.fOutputCoverage, args.fOutputCoverage,
args.fOutputCoverage, args.fOutputCoverage);
}
}
}
