/*
* Copyright 2016 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkArenaAlloc.h"
#include "SkBlitter.h"
#include "SkBlendModePriv.h"
#include "SkColor.h"
#include "SkColorFilter.h"
#include "SkColorSpaceXformer.h"
#include "SkOpts.h"
#include "SkPM4f.h"
#include "SkPM4fPriv.h"
#include "SkRasterPipeline.h"
#include "SkShader.h"
#include "SkShaderBase.h"
#include "SkUtils.h"
#include "../jumper/SkJumper.h"
class SkRasterPipelineBlitter final : public SkBlitter {
public:
// This is our common entrypoint for creating the blitter once we've sorted out shaders.
static SkBlitter* Create(const SkPixmap&, const SkPaint&, SkArenaAlloc*,
const SkRasterPipeline& shaderPipeline,
SkShaderBase::Context*,
bool is_opaque, bool is_constant);
SkRasterPipelineBlitter(SkPixmap dst,
SkBlendMode blend,
SkArenaAlloc* alloc,
SkShaderBase::Context* burstCtx)
: fDst(dst)
, fBlend(blend)
, fAlloc(alloc)
, fBurstCtx(burstCtx)
, fColorPipeline(alloc)
{}
void blitH (int x, int y, int w) override;
void blitAntiH (int x, int y, const SkAlpha[], const int16_t[]) override;
void blitAntiH2(int x, int y, U8CPU a0, U8CPU a1) override;
void blitAntiV2(int x, int y, U8CPU a0, U8CPU a1) override;
void blitMask (const SkMask&, const SkIRect& clip) override;
void blitRect (int x, int y, int width, int height) override;
void blitV (int x, int y, int height, SkAlpha alpha) override;
private:
void append_load_dst(SkRasterPipeline*) const;
void append_store (SkRasterPipeline*) const;
// If we have an burst context, use it to fill our shader buffer.
void burst_shade(int x, int y, int w);
SkPixmap fDst;
SkBlendMode fBlend;
SkArenaAlloc* fAlloc;
SkShaderBase::Context* fBurstCtx;
SkRasterPipeline fColorPipeline;
SkJumper_MemoryCtx fShaderOutput = {nullptr,0}, // Possibly updated each call to burst_shade().
fDstPtr = {nullptr,0}, // Always points to the top-left of fDst.
fMaskPtr = {nullptr,0}; // Updated each call to blitMask().
// We may be able to specialize blitH() or blitRect() into a memset.
bool fCanMemsetInBlitRect = false;
uint64_t fMemsetColor = 0; // Big enough for largest dst format, F16.
// Built lazily on first use.
std::function<void(size_t, size_t, size_t, size_t)> fBlitRect,
fBlitAntiH,
fBlitMaskA8,
fBlitMaskLCD16;
// These values are pointed to by the blit pipelines above,
// which allows us to adjust them from call to call.
float fCurrentCoverage = 0.0f;
float fDitherRate = 0.0f;
std::vector<SkPM4f> fShaderBuffer;
typedef SkBlitter INHERITED;
};
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_constant_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, alloc, dstCS, paint, nullptr, ctm})) {
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* SkCreateRasterPipelineBlitter(const SkPixmap& dst,
const SkPaint& paint,
const SkRasterPipeline& shaderPipeline,
bool is_opaque,
SkArenaAlloc* alloc) {
bool is_constant = false; // If this were the case, it'd be better to just set a paint color.
return SkRasterPipelineBlitter::Create(dst, paint, alloc, shaderPipeline, nullptr,
is_opaque, is_constant);
}
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 kRGB_888x_SkColorType:
case kRGBA_8888_SkColorType:
case kBGRA_8888_SkColorType: blitter->fDitherRate = 1/255.0f; break;
case kRGB_101010x_SkColorType:
case kRGBA_1010102_SkColorType: blitter->fDitherRate = 1/1023.0f; 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 constantColor;
SkJumper_MemoryCtx constantColorPtr = { &constantColor, 0 };
colorPipeline->append(SkRasterPipeline::store_f32, &constantColorPtr);
colorPipeline->run(0,0,1,1);
colorPipeline->reset();
colorPipeline->append_constant_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 = SkJumper_MemoryCtx{&blitter->fMemsetColor, 0};
blitter->append_store(&p);
p.run(0,0,1,1);
blitter->fCanMemsetInBlitRect = true;
}
blitter->fDstPtr = SkJumper_MemoryCtx{
blitter->fDst.writable_addr(),
blitter->fDst.rowBytesAsPixels(),
};
return blitter;
}
void SkRasterPipelineBlitter::append_load_dst(SkRasterPipeline* p) const {
const void* ctx = &fDstPtr;
switch (fDst.info().colorType()) {
default: break;
case kGray_8_SkColorType: p->append(SkRasterPipeline::load_g8_dst, ctx); break;
case kAlpha_8_SkColorType: p->append(SkRasterPipeline::load_a8_dst, ctx); break;
case kRGB_565_SkColorType: p->append(SkRasterPipeline::load_565_dst, ctx); break;
case kARGB_4444_SkColorType: p->append(SkRasterPipeline::load_4444_dst, ctx); break;
case kBGRA_8888_SkColorType: p->append(SkRasterPipeline::load_bgra_dst, ctx); break;
case kRGBA_8888_SkColorType: p->append(SkRasterPipeline::load_8888_dst, ctx); break;
case kRGBA_1010102_SkColorType: p->append(SkRasterPipeline::load_1010102_dst, ctx); break;
case kRGBA_F16_SkColorType: p->append(SkRasterPipeline::load_f16_dst, ctx); break;
case kRGB_888x_SkColorType: p->append(SkRasterPipeline::load_8888_dst, ctx);
p->append(SkRasterPipeline::force_opaque_dst ); break;
case kRGB_101010x_SkColorType: p->append(SkRasterPipeline::load_1010102_dst, ctx);
p->append(SkRasterPipeline::force_opaque_dst ); break;
}
if (fDst.info().gammaCloseToSRGB()) {
p->append(SkRasterPipeline::from_srgb_dst);
}
if (fDst.info().alphaType() == kUnpremul_SkAlphaType) {
p->append(SkRasterPipeline::premul_dst);
}
}
void SkRasterPipelineBlitter::append_store(SkRasterPipeline* p) const {
if (fDst.info().alphaType() == kUnpremul_SkAlphaType) {
p->append(SkRasterPipeline::unpremul);
}
if (fDst.info().gammaCloseToSRGB()) {
p->append(SkRasterPipeline::to_srgb);
}
if (fDitherRate > 0.0f) {
// We dither after any sRGB transfer function to make sure our 1/255.0f is sensible
// over the whole range. If we did it before, 1/255.0f is too big a rate near zero.
p->append(SkRasterPipeline::dither, &fDitherRate);
}
const void* ctx = &fDstPtr;
switch (fDst.info().colorType()) {
default: break;
case kGray_8_SkColorType: p->append(SkRasterPipeline::luminance_to_alpha);
p->append(SkRasterPipeline::store_a8, ctx); break;
case kAlpha_8_SkColorType: p->append(SkRasterPipeline::store_a8, ctx); break;
case kRGB_565_SkColorType: p->append(SkRasterPipeline::store_565, ctx); break;
case kARGB_4444_SkColorType: p->append(SkRasterPipeline::store_4444, ctx); break;
case kBGRA_8888_SkColorType: p->append(SkRasterPipeline::store_bgra, ctx); break;
case kRGBA_8888_SkColorType: p->append(SkRasterPipeline::store_8888, ctx); break;
case kRGBA_1010102_SkColorType: p->append(SkRasterPipeline::store_1010102, ctx); break;
case kRGBA_F16_SkColorType: p->append(SkRasterPipeline::store_f16, ctx); break;
case kRGB_888x_SkColorType: p->append(SkRasterPipeline::force_opaque );
p->append(SkRasterPipeline::store_8888, ctx); break;
case kRGB_101010x_SkColorType: p->append(SkRasterPipeline::force_opaque );
p->append(SkRasterPipeline::store_1010102, ctx); break;
}
}
void SkRasterPipelineBlitter::burst_shade(int x, int y, int w) {
SkASSERT(fBurstCtx);
if (w > SkToInt(fShaderBuffer.size())) {
fShaderBuffer.resize(w);
}
fBurstCtx->shadeSpan4f(x,y, fShaderBuffer.data(), w);
// We'll be reading from fShaderOutput.pixels + x, so back up by x.
fShaderOutput = SkJumper_MemoryCtx{ fShaderBuffer.data() - x, 0 };
}
void SkRasterPipelineBlitter::blitH(int x, int y, int w) {
this->blitRect(x,y,w,1);
}
void SkRasterPipelineBlitter::blitRect(int x, int y, int w, int h) {
if (fCanMemsetInBlitRect) {
for (int ylimit = y+h; y < ylimit; y++) {
switch (fDst.shiftPerPixel()) {
case 0: memset (fDst.writable_addr8 (x,y), fMemsetColor, w); break;
case 1: sk_memset16(fDst.writable_addr16(x,y), fMemsetColor, w); break;
case 2: sk_memset32(fDst.writable_addr32(x,y), fMemsetColor, w); break;
case 3: sk_memset64(fDst.writable_addr64(x,y), fMemsetColor, w); break;
default: break;
}
}
return;
}
if (!fBlitRect) {
SkRasterPipeline p(fAlloc);
p.extend(fColorPipeline);
if (fBlend == SkBlendMode::kSrcOver
&& (fDst.info().colorType() == kRGBA_8888_SkColorType ||
fDst.info().colorType() == kBGRA_8888_SkColorType)
&& !fDst.colorSpace()
&& fDst.info().alphaType() != kUnpremul_SkAlphaType
&& fDitherRate == 0.0f) {
auto stage = fDst.info().colorType() == kRGBA_8888_SkColorType
? SkRasterPipeline::srcover_rgba_8888
: SkRasterPipeline::srcover_bgra_8888;
p.append(stage, &fDstPtr);
} else {
if (fBlend != SkBlendMode::kSrc) {
this->append_load_dst(&p);
SkBlendMode_AppendStages(fBlend, &p);
}
this->append_store(&p);
}
fBlitRect = p.compile();
}
if (fBurstCtx) {
// We can only burst shade one row at a time.
for (int ylimit = y+h; y < ylimit; y++) {
this->burst_shade(x,y,w);
fBlitRect(x,y, w,1);
}
} else {
// If not bursting we can blit the entire rect at once.
fBlitRect(x,y,w,h);
}
}
void SkRasterPipelineBlitter::blitAntiH(int x, int y, const SkAlpha aa[], const int16_t runs[]) {
if (!fBlitAntiH) {
SkRasterPipeline p(fAlloc);
p.extend(fColorPipeline);
if (SkBlendMode_ShouldPreScaleCoverage(fBlend, /*rgb_coverage=*/false)) {
p.append(SkRasterPipeline::scale_1_float, &fCurrentCoverage);
this->append_load_dst(&p);
SkBlendMode_AppendStages(fBlend, &p);
} else {
this->append_load_dst(&p);
SkBlendMode_AppendStages(fBlend, &p);
p.append(SkRasterPipeline::lerp_1_float, &fCurrentCoverage);
}
this->append_store(&p);
fBlitAntiH = p.compile();
}
for (int16_t run = *runs; run > 0; run = *runs) {
switch (*aa) {
case 0x00: break;
case 0xff: this->blitH(x,y,run); break;
default:
fCurrentCoverage = *aa * (1/255.0f);
if (fBurstCtx) {
this->burst_shade(x,y,run);
}
fBlitAntiH(x,y,run,1);
}
x += run;
runs += run;
aa += run;
}
}
void SkRasterPipelineBlitter::blitAntiH2(int x, int y, U8CPU a0, U8CPU a1) {
SkIRect clip = {x,y, x+2,y+1};
uint8_t coverage[] = { (uint8_t)a0, (uint8_t)a1 };
SkMask mask;
mask.fImage = coverage;
mask.fBounds = clip;
mask.fRowBytes = 2;
mask.fFormat = SkMask::kA8_Format;
this->blitMask(mask, clip);
}
void SkRasterPipelineBlitter::blitAntiV2(int x, int y, U8CPU a0, U8CPU a1) {
SkIRect clip = {x,y, x+1,y+2};
uint8_t coverage[] = { (uint8_t)a0, (uint8_t)a1 };
SkMask mask;
mask.fImage = coverage;
mask.fBounds = clip;
mask.fRowBytes = 1;
mask.fFormat = SkMask::kA8_Format;
this->blitMask(mask, clip);
}
void SkRasterPipelineBlitter::blitV(int x, int y, int height, SkAlpha alpha) {
SkIRect clip = {x,y, x+1,y+height};
SkMask mask;
mask.fImage = α
mask.fBounds = clip;
mask.fRowBytes = 0; // so we reuse the 1 "row" for all of height
mask.fFormat = SkMask::kA8_Format;
this->blitMask(mask, clip);
}
void SkRasterPipelineBlitter::blitMask(const SkMask& mask, const SkIRect& clip) {
if (mask.fFormat == SkMask::kBW_Format) {
// TODO: native BW masks?
return INHERITED::blitMask(mask, clip);
}
// We'll use the first (A8) plane of any mask and ignore the other two, just like Ganesh.
SkMask::Format effectiveMaskFormat = mask.fFormat == SkMask::k3D_Format ? SkMask::kA8_Format
: mask.fFormat;
// Lazily build whichever pipeline we need, specialized for each mask format.
if (effectiveMaskFormat == SkMask::kA8_Format && !fBlitMaskA8) {
SkRasterPipeline p(fAlloc);
p.extend(fColorPipeline);
if (SkBlendMode_ShouldPreScaleCoverage(fBlend, /*rgb_coverage=*/false)) {
p.append(SkRasterPipeline::scale_u8, &fMaskPtr);
this->append_load_dst(&p);
SkBlendMode_AppendStages(fBlend, &p);
} else {
this->append_load_dst(&p);
SkBlendMode_AppendStages(fBlend, &p);
p.append(SkRasterPipeline::lerp_u8, &fMaskPtr);
}
this->append_store(&p);
fBlitMaskA8 = p.compile();
}
if (effectiveMaskFormat == SkMask::kLCD16_Format && !fBlitMaskLCD16) {
SkRasterPipeline p(fAlloc);
p.extend(fColorPipeline);
if (SkBlendMode_ShouldPreScaleCoverage(fBlend, /*rgb_coverage=*/true)) {
// Somewhat unusually, scale_565 needs dst loaded first.
this->append_load_dst(&p);
p.append(SkRasterPipeline::scale_565, &fMaskPtr);
SkBlendMode_AppendStages(fBlend, &p);
} else {
this->append_load_dst(&p);
SkBlendMode_AppendStages(fBlend, &p);
p.append(SkRasterPipeline::lerp_565, &fMaskPtr);
}
this->append_store(&p);
fBlitMaskLCD16 = p.compile();
}
std::function<void(size_t,size_t,size_t,size_t)>* blitter = nullptr;
// Update fMaskPtr to point "into" this current mask, but lined up with fDstPtr at (0,0).
switch (effectiveMaskFormat) {
case SkMask::kA8_Format:
fMaskPtr.stride = mask.fRowBytes;
fMaskPtr.pixels = (uint8_t*)mask.fImage - mask.fBounds.left()
- mask.fBounds.top() * fMaskPtr.stride;
blitter = &fBlitMaskA8;
break;
case SkMask::kLCD16_Format:
fMaskPtr.stride = mask.fRowBytes / 2;
fMaskPtr.pixels = (uint16_t*)mask.fImage - mask.fBounds.left()
- mask.fBounds.top() * fMaskPtr.stride;
blitter = &fBlitMaskLCD16;
break;
default:
return;
}
SkASSERT(blitter);
if (fBurstCtx) {
// We can only burst shade one row at a time.
int x = clip.left();
for (int y = clip.top(); y < clip.bottom(); y++) {
this->burst_shade(x,y,clip.width());
(*blitter)(x,y, clip.width(),1);
}
} else {
// If not bursting we can blit the entire mask at once.
(*blitter)(clip.left(),clip.top(), clip.width(),clip.height());
}
}