SkBlitter* SkCreateRasterPipelineBlitter(const SkPixmap& dst,
const SkPaint& paint,
const SkMatrix& ctm,
SkArenaAlloc* alloc) {
SkColorSpace* dstCS = dst.colorSpace();
SkPM4f paintColor = SkPM4f_from_SkColor(paint.getColor(), dstCS);
auto shader = as_SB(paint.getShader());
SkRasterPipeline_<256> shaderPipeline;
if (!shader) {
// Having no shader makes things nice and easy... just use the paint color.
shaderPipeline.append_uniform_color(alloc, paintColor);
bool is_opaque = paintColor.a() == 1.0f,
is_constant = true;
return SkRasterPipelineBlitter::Create(dst, paint, alloc,
shaderPipeline, nullptr,
is_opaque, is_constant);
}
bool is_opaque = shader->isOpaque() && paintColor.a() == 1.0f;
bool is_constant = shader->isConstant();
// Check whether the shader prefers to run in burst mode.
if (auto* burstCtx = shader->makeBurstPipelineContext(
SkShaderBase::ContextRec(paint, ctm, nullptr, SkShaderBase::ContextRec::kPM4f_DstType,
dstCS), alloc)) {
return SkRasterPipelineBlitter::Create(dst, paint, alloc,
shaderPipeline, burstCtx,
is_opaque, is_constant);
}
if (shader->appendStages(&shaderPipeline, dstCS, alloc, ctm, paint)) {
if (paintColor.a() != 1.0f) {
shaderPipeline.append(SkRasterPipeline::scale_1_float,
alloc->make<float>(paintColor.a()));
}
return SkRasterPipelineBlitter::Create(dst, paint, alloc, shaderPipeline, nullptr,
is_opaque, is_constant);
}
// The shader has opted out of drawing anything.
return alloc->make<SkNullBlitter>();
}
SkBlitter* SkRasterPipelineBlitter::Create(const SkPixmap& dst,
const SkPaint& paint,
SkArenaAlloc* alloc,
const SkRasterPipeline& shaderPipeline,
SkShaderBase::Context* burstCtx,
bool is_opaque,
bool is_constant) {
auto blitter = alloc->make<SkRasterPipelineBlitter>(dst,
paint.getBlendMode(),
alloc,
burstCtx);
// Our job in this factory is to fill out the blitter's color pipeline.
// This is the common front of the full blit pipelines, each constructed lazily on first use.
// The full blit pipelines handle reading and writing the dst, blending, coverage, dithering.
auto colorPipeline = &blitter->fColorPipeline;
// Let's get the shader in first.
if (burstCtx) {
colorPipeline->append(SkRasterPipeline::load_f32, &blitter->fShaderOutput);
} else {
colorPipeline->extend(shaderPipeline);
}
// If there's a color filter it comes next.
if (auto colorFilter = paint.getColorFilter()) {
colorFilter->appendStages(colorPipeline, dst.colorSpace(), alloc, is_opaque);
is_opaque = is_opaque && (colorFilter->getFlags() & SkColorFilter::kAlphaUnchanged_Flag);
}
// Not all formats make sense to dither (think, F16). We set their dither rate to zero.
// We need to decide if we're going to dither now to keep is_constant accurate.
if (paint.isDither()) {
switch (dst.info().colorType()) {
default: blitter->fDitherRate = 0.0f; break;
case kARGB_4444_SkColorType: blitter->fDitherRate = 1/15.0f; break;
case kRGB_565_SkColorType: blitter->fDitherRate = 1/63.0f; break;
case kGray_8_SkColorType:
case kRGBA_8888_SkColorType:
case kBGRA_8888_SkColorType: blitter->fDitherRate = 1/255.0f; break;
}
// TODO: for constant colors, we could try to measure the effect of dithering, and if
// it has no value (i.e. all variations result in the same 32bit color, then we
// could disable it (for speed, by not adding the stage).
}
is_constant = is_constant && (blitter->fDitherRate == 0.0f);
// We're logically done here. The code between here and return blitter is all optimization.
// A pipeline that's still constant here can collapse back into a constant color.
if (is_constant) {
SkPM4f storage;
SkPM4f* constantColor = &storage;
colorPipeline->append(SkRasterPipeline::store_f32, &constantColor);
colorPipeline->run(0,0,1);
colorPipeline->reset();
colorPipeline->append_uniform_color(alloc, *constantColor);
is_opaque = constantColor->a() == 1.0f;
}
// We can strength-reduce SrcOver into Src when opaque.
if (is_opaque && blitter->fBlend == SkBlendMode::kSrcOver) {
blitter->fBlend = SkBlendMode::kSrc;
}
// When we're drawing a constant color in Src mode, we can sometimes just memset.
// (The previous two optimizations help find more opportunities for this one.)
if (is_constant && blitter->fBlend == SkBlendMode::kSrc) {
// Run our color pipeline all the way through to produce what we'd memset when we can.
// Not all blits can memset, so we need to keep colorPipeline too.
SkRasterPipeline_<256> p;
p.extend(*colorPipeline);
blitter->fDstPtr = &blitter->fMemsetColor;
blitter->append_store(&p);
p.run(0,0,1);
blitter->fCanMemsetInBlitH = true;
}
return blitter;
}
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;
}