bool SkComposeShader::onAppendStages(const StageRec& rec) const {
struct Storage {
float fRGBA[4 * SkJumper_kMaxStride];
float fAlpha;
};
auto storage = rec.fAlloc->make<Storage>();
if (!as_SB(fSrc)->appendStages(rec)) {
return false;
}
// This outputs r,g,b,a, which we'll need later when we apply the mode, but we save it off now
// since fShaderB will overwrite them.
rec.fPipeline->append(SkRasterPipeline::store_rgba, storage->fRGBA);
if (!as_SB(fDst)->appendStages(rec)) {
return false;
}
// We now have our logical 'dst' in r,g,b,a, but we need it in dr,dg,db,da for the mode/lerp
// so we have to shuttle them. If we had a stage the would load_into_dst, then we could
// reverse the two shader invocations, and avoid this move...
rec.fPipeline->append(SkRasterPipeline::move_src_dst);
rec.fPipeline->append(SkRasterPipeline::load_rgba, storage->fRGBA);
if (!this->isJustLerp()) {
SkBlendMode_AppendStages(fMode, rec.fPipeline);
}
if (!this->isJustMode()) {
rec.fPipeline->append(SkRasterPipeline::lerp_1_float, &fLerpT);
}
return true;
}
SkBlitter* SkRasterPipelineBlitter::Create(const SkPixmap& dst,
const SkPaint& paint,
const SkMatrix& ctm,
SkArenaAlloc* alloc) {
auto blitter = alloc->make<SkRasterPipelineBlitter>(
dst,
paint.getBlendMode(),
SkPM4f_from_SkColor(paint.getColor(), dst.colorSpace()));
SkBlendMode* blend = &blitter->fBlend;
SkPM4f* paintColor = &blitter->fPaintColor;
SkRasterPipeline* pipeline = &blitter->fShader;
SkShader* shader = paint.getShader();
SkColorFilter* colorFilter = paint.getColorFilter();
// TODO: all temporary
if (!supported(dst.info()) || !SkBlendMode_AppendStages(*blend)) {
return nullptr;
}
bool is_opaque = paintColor->a() == 1.0f,
is_constant = true;
if (shader) {
pipeline->append(SkRasterPipeline::seed_shader, &blitter->fCurrentY);
if (!shader->appendStages(pipeline, dst.colorSpace(), alloc, ctm, paint)) {
return nullptr;
}
if (!is_opaque) {
pipeline->append(SkRasterPipeline::scale_1_float,
&paintColor->fVec[SkPM4f::A]);
}
is_opaque = is_opaque && shader->isOpaque();
is_constant = shader->isConstant();
} else {
pipeline->append(SkRasterPipeline::constant_color, paintColor);
}
if (colorFilter) {
if (!colorFilter->appendStages(pipeline, dst.colorSpace(), alloc, is_opaque)) {
return nullptr;
}
is_opaque = is_opaque && (colorFilter->getFlags() & SkColorFilter::kAlphaUnchanged_Flag);
}
if (is_constant) {
pipeline->append(SkRasterPipeline::store_f32, &paintColor);
pipeline->run(0,1);
*pipeline = SkRasterPipeline();
pipeline->append(SkRasterPipeline::constant_color, paintColor);
is_opaque = paintColor->a() == 1.0f;
}
if (is_opaque && *blend == SkBlendMode::kSrcOver) {
*blend = SkBlendMode::kSrc;
}
if (is_constant && *blend == SkBlendMode::kSrc) {
SkRasterPipeline p;
p.extend(*pipeline);
blitter->fDstPtr = &blitter->fMemsetColor;
blitter->append_store(&p);
p.run(0,1);
blitter->fCanMemsetInBlitH = true;
}
return blitter;
}
void SkRasterPipelineBlitter::append_blend(SkRasterPipeline* p) const {
SkAssertResult(SkBlendMode_AppendStages(fBlend, p));
}
