SkPDFAlphaFunctionShader::SkPDFAlphaFunctionShader(SkPDFShader::State* state)
: fState(state) {
SkRect bbox;
bbox.set(fState.get()->fBBox);
fColorShader.reset(
SkPDFShader::GetPDFShaderByState(state->CreateOpaqueState()));
// Create resource dict with alpha graphics state as G0 and
// pattern shader as P0, then write content stream.
SkAutoTUnref<SkPDFGraphicState> alphaGs(CreateSMaskGraphicState());
fResourceDict.reset(
get_gradient_resource_dict(fColorShader.get(), alphaGs.get()));
SkAutoTUnref<SkStream> colorStream(
create_pattern_fill_content(0, bbox));
setData(colorStream.get());
populate_tiling_pattern_dict(this, bbox, fResourceDict.get(),
SkMatrix::I());
}
SkPDFAlphaFunctionShader* SkPDFAlphaFunctionShader::Create(
SkPDFCanon* canon,
SkScalar dpi,
SkAutoTDelete<SkPDFShader::State>* autoState) {
const SkPDFShader::State& state = **autoState;
SkRect bbox;
bbox.set(state.fBBox);
SkAutoTDelete<SkPDFShader::State> opaqueState(state.CreateOpaqueState());
SkAutoTUnref<SkPDFObject> colorShader(
get_pdf_shader_by_state(canon, dpi, &opaqueState));
if (!colorShader) {
return NULL;
}
// Create resource dict with alpha graphics state as G0 and
// pattern shader as P0, then write content stream.
SkAutoTUnref<SkPDFObject> alphaGs(
create_smask_graphic_state(canon, dpi, state));
SkPDFAlphaFunctionShader* alphaFunctionShader =
SkNEW_ARGS(SkPDFAlphaFunctionShader, (autoState->detach()));
SkAutoTUnref<SkPDFDict> resourceDict(
get_gradient_resource_dict(colorShader.get(), alphaGs.get()));
SkAutoTDelete<SkStream> colorStream(
create_pattern_fill_content(0, bbox));
alphaFunctionShader->setData(colorStream.get());
populate_tiling_pattern_dict(alphaFunctionShader, bbox, resourceDict.get(),
SkMatrix::I());
canon->addAlphaShader(alphaFunctionShader);
return alphaFunctionShader;
}