sk_sp<GrFragmentProcessor> SkPerlinNoiseShader::asFragmentProcessor(const AsFPArgs& args) const {
SkASSERT(args.fContext);
SkMatrix localMatrix = this->getLocalMatrix();
if (args.fLocalMatrix) {
localMatrix.preConcat(*args.fLocalMatrix);
}
SkMatrix matrix = *args.fViewMatrix;
matrix.preConcat(localMatrix);
if (0 == fNumOctaves) {
if (kFractalNoise_Type == fType) {
// Extract the incoming alpha and emit rgba = (a/4, a/4, a/4, a/2)
// TODO: Either treat the output of this shader as sRGB or allow client to specify a
// color space of the noise. Either way, this case (and the GLSL) need to convert to
// the destination.
sk_sp<GrFragmentProcessor> inner(
GrConstColorProcessor::Make(GrColor4f::FromGrColor(0x80404040),
GrConstColorProcessor::kModulateRGBA_InputMode));
return GrFragmentProcessor::MulOutputByInputAlpha(std::move(inner));
}
// Emit zero.
return GrConstColorProcessor::Make(GrColor4f::TransparentBlack(),
GrConstColorProcessor::kIgnore_InputMode);
}
// Either we don't stitch tiles, either we have a valid tile size
SkASSERT(!fStitchTiles || !fTileSize.isEmpty());
SkPerlinNoiseShader::PaintingData* paintingData =
new PaintingData(fTileSize, fSeed, fBaseFrequencyX, fBaseFrequencyY, matrix);
SkAutoTUnref<GrTexture> permutationsTexture(
GrRefCachedBitmapTexture(args.fContext, paintingData->getPermutationsBitmap(),
GrTextureParams::ClampNoFilter(), args.fGammaTreatment));
SkAutoTUnref<GrTexture> noiseTexture(
GrRefCachedBitmapTexture(args.fContext, paintingData->getNoiseBitmap(),
GrTextureParams::ClampNoFilter(), args.fGammaTreatment));
SkMatrix m = *args.fViewMatrix;
m.setTranslateX(-localMatrix.getTranslateX() + SK_Scalar1);
m.setTranslateY(-localMatrix.getTranslateY() + SK_Scalar1);
if ((permutationsTexture) && (noiseTexture)) {
sk_sp<GrFragmentProcessor> inner(
GrPerlinNoiseEffect::Make(fType,
fNumOctaves,
fStitchTiles,
paintingData,
permutationsTexture, noiseTexture,
m));
return GrFragmentProcessor::MulOutputByInputAlpha(std::move(inner));
}
delete paintingData;
return nullptr;
}
const GrFragmentProcessor* SkPerlinNoiseShader::asFragmentProcessor(
GrContext* context,
const SkMatrix& viewM,
const SkMatrix* externalLocalMatrix,
SkFilterQuality) const {
SkASSERT(context);
SkMatrix localMatrix = this->getLocalMatrix();
if (externalLocalMatrix) {
localMatrix.preConcat(*externalLocalMatrix);
}
SkMatrix matrix = viewM;
matrix.preConcat(localMatrix);
if (0 == fNumOctaves) {
if (kFractalNoise_Type == fType) {
// Extract the incoming alpha and emit rgba = (a/4, a/4, a/4, a/2)
SkAutoTUnref<const GrFragmentProcessor> inner(
GrConstColorProcessor::Create(0x80404040,
GrConstColorProcessor::kModulateRGBA_InputMode));
return GrFragmentProcessor::MulOutputByInputAlpha(inner);
}
// Emit zero.
return GrConstColorProcessor::Create(0x0, GrConstColorProcessor::kIgnore_InputMode);
}
// Either we don't stitch tiles, either we have a valid tile size
SkASSERT(!fStitchTiles || !fTileSize.isEmpty());
SkPerlinNoiseShader::PaintingData* paintingData =
new PaintingData(fTileSize, fSeed, fBaseFrequencyX, fBaseFrequencyY, matrix);
SkAutoTUnref<GrTexture> permutationsTexture(
GrRefCachedBitmapTexture(context, paintingData->getPermutationsBitmap(),
GrTextureParams::ClampNoFilter()));
SkAutoTUnref<GrTexture> noiseTexture(
GrRefCachedBitmapTexture(context, paintingData->getNoiseBitmap(),
GrTextureParams::ClampNoFilter()));
SkMatrix m = viewM;
m.setTranslateX(-localMatrix.getTranslateX() + SK_Scalar1);
m.setTranslateY(-localMatrix.getTranslateY() + SK_Scalar1);
if ((permutationsTexture) && (noiseTexture)) {
SkAutoTUnref<GrFragmentProcessor> inner(
GrPerlinNoiseEffect::Create(fType,
fNumOctaves,
fStitchTiles,
paintingData,
permutationsTexture, noiseTexture,
m));
return GrFragmentProcessor::MulOutputByInputAlpha(inner);
}
delete paintingData;
return nullptr;
}