1 /*
2 * Copyright 2016 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8 #include "SkArenaAlloc.h"
9 #include "SkBlitter.h"
10 #include "SkBlendModePriv.h"
11 #include "SkColor.h"
12 #include "SkColorFilter.h"
13 #include "SkColorSpaceXformer.h"
14 #include "SkOpts.h"
15 #include "SkPM4f.h"
16 #include "SkPM4fPriv.h"
17 #include "SkRasterPipeline.h"
18 #include "SkShader.h"
19 #include "SkShaderBase.h"
20 #include "SkUtils.h"
21 #include "../jumper/SkJumper.h"
22
23 class SkRasterPipelineBlitter final : public SkBlitter {
24 public:
25 // This is our common entrypoint for creating the blitter once we've sorted out shaders.
26 static SkBlitter* Create(const SkPixmap&, const SkPaint&, SkArenaAlloc*,
27 const SkRasterPipeline& shaderPipeline,
28 SkShaderBase::Context*,
29 bool is_opaque, bool is_constant);
30
SkRasterPipelineBlitter(SkPixmap dst,SkBlendMode blend,SkArenaAlloc * alloc,SkShaderBase::Context * burstCtx)31 SkRasterPipelineBlitter(SkPixmap dst,
32 SkBlendMode blend,
33 SkArenaAlloc* alloc,
34 SkShaderBase::Context* burstCtx)
35 : fDst(dst)
36 , fBlend(blend)
37 , fAlloc(alloc)
38 , fBurstCtx(burstCtx)
39 , fColorPipeline(alloc)
40 {}
41
42 void blitH (int x, int y, int w) override;
43 void blitAntiH (int x, int y, const SkAlpha[], const int16_t[]) override;
44 void blitAntiH2(int x, int y, U8CPU a0, U8CPU a1) override;
45 void blitAntiV2(int x, int y, U8CPU a0, U8CPU a1) override;
46 void blitMask (const SkMask&, const SkIRect& clip) override;
47 void blitRect (int x, int y, int width, int height) override;
48 void blitV (int x, int y, int height, SkAlpha alpha) override;
49
50 private:
51 void append_load_dst(SkRasterPipeline*) const;
52 void append_store (SkRasterPipeline*) const;
53
54 // If we have an burst context, use it to fill our shader buffer.
55 void burst_shade(int x, int y, int w);
56
57 SkPixmap fDst;
58 SkBlendMode fBlend;
59 SkArenaAlloc* fAlloc;
60 SkShaderBase::Context* fBurstCtx;
61 SkRasterPipeline fColorPipeline;
62
63 SkJumper_MemoryCtx fShaderOutput = {nullptr,0}, // Possibly updated each call to burst_shade().
64 fDstPtr = {nullptr,0}, // Always points to the top-left of fDst.
65 fMaskPtr = {nullptr,0}; // Updated each call to blitMask().
66
67 // We may be able to specialize blitH() or blitRect() into a memset.
68 bool fCanMemsetInBlitRect = false;
69 uint64_t fMemsetColor = 0; // Big enough for largest dst format, F16.
70
71 // Built lazily on first use.
72 std::function<void(size_t, size_t, size_t, size_t)> fBlitRect,
73 fBlitAntiH,
74 fBlitMaskA8,
75 fBlitMaskLCD16;
76
77 // These values are pointed to by the blit pipelines above,
78 // which allows us to adjust them from call to call.
79 float fCurrentCoverage = 0.0f;
80 float fDitherRate = 0.0f;
81
82 std::vector<SkPM4f> fShaderBuffer;
83
84 typedef SkBlitter INHERITED;
85 };
86
SkCreateRasterPipelineBlitter(const SkPixmap & dst,const SkPaint & paint,const SkMatrix & ctm,SkArenaAlloc * alloc)87 SkBlitter* SkCreateRasterPipelineBlitter(const SkPixmap& dst,
88 const SkPaint& paint,
89 const SkMatrix& ctm,
90 SkArenaAlloc* alloc) {
91 SkColorSpace* dstCS = dst.colorSpace();
92 SkPM4f paintColor = SkPM4f_from_SkColor(paint.getColor(), dstCS);
93 auto shader = as_SB(paint.getShader());
94
95 SkRasterPipeline_<256> shaderPipeline;
96 if (!shader) {
97 // Having no shader makes things nice and easy... just use the paint color.
98 shaderPipeline.append_constant_color(alloc, paintColor);
99 bool is_opaque = paintColor.a() == 1.0f,
100 is_constant = true;
101 return SkRasterPipelineBlitter::Create(dst, paint, alloc,
102 shaderPipeline, nullptr,
103 is_opaque, is_constant);
104 }
105
106 bool is_opaque = shader->isOpaque() && paintColor.a() == 1.0f;
107 bool is_constant = shader->isConstant();
108
109 // Check whether the shader prefers to run in burst mode.
110 if (auto* burstCtx = shader->makeBurstPipelineContext(
111 SkShaderBase::ContextRec(paint, ctm, nullptr, SkShaderBase::ContextRec::kPM4f_DstType,
112 dstCS), alloc)) {
113 return SkRasterPipelineBlitter::Create(dst, paint, alloc,
114 shaderPipeline, burstCtx,
115 is_opaque, is_constant);
116 }
117
118 if (shader->appendStages({&shaderPipeline, alloc, dstCS, paint, nullptr, ctm})) {
119 if (paintColor.a() != 1.0f) {
120 shaderPipeline.append(SkRasterPipeline::scale_1_float,
121 alloc->make<float>(paintColor.a()));
122 }
123 return SkRasterPipelineBlitter::Create(dst, paint, alloc, shaderPipeline, nullptr,
124 is_opaque, is_constant);
125 }
126
127 // The shader has opted out of drawing anything.
128 return alloc->make<SkNullBlitter>();
129 }
130
SkCreateRasterPipelineBlitter(const SkPixmap & dst,const SkPaint & paint,const SkRasterPipeline & shaderPipeline,bool is_opaque,SkArenaAlloc * alloc)131 SkBlitter* SkCreateRasterPipelineBlitter(const SkPixmap& dst,
132 const SkPaint& paint,
133 const SkRasterPipeline& shaderPipeline,
134 bool is_opaque,
135 SkArenaAlloc* alloc) {
136 bool is_constant = false; // If this were the case, it'd be better to just set a paint color.
137 return SkRasterPipelineBlitter::Create(dst, paint, alloc, shaderPipeline, nullptr,
138 is_opaque, is_constant);
139 }
140
Create(const SkPixmap & dst,const SkPaint & paint,SkArenaAlloc * alloc,const SkRasterPipeline & shaderPipeline,SkShaderBase::Context * burstCtx,bool is_opaque,bool is_constant)141 SkBlitter* SkRasterPipelineBlitter::Create(const SkPixmap& dst,
142 const SkPaint& paint,
143 SkArenaAlloc* alloc,
144 const SkRasterPipeline& shaderPipeline,
145 SkShaderBase::Context* burstCtx,
146 bool is_opaque,
147 bool is_constant) {
148 auto blitter = alloc->make<SkRasterPipelineBlitter>(dst,
149 paint.getBlendMode(),
150 alloc,
151 burstCtx);
152
153 // Our job in this factory is to fill out the blitter's color pipeline.
154 // This is the common front of the full blit pipelines, each constructed lazily on first use.
155 // The full blit pipelines handle reading and writing the dst, blending, coverage, dithering.
156 auto colorPipeline = &blitter->fColorPipeline;
157
158 // Let's get the shader in first.
159 if (burstCtx) {
160 colorPipeline->append(SkRasterPipeline::load_f32, &blitter->fShaderOutput);
161 } else {
162 colorPipeline->extend(shaderPipeline);
163 }
164
165 // If there's a color filter it comes next.
166 if (auto colorFilter = paint.getColorFilter()) {
167 colorFilter->appendStages(colorPipeline, dst.colorSpace(), alloc, is_opaque);
168 is_opaque = is_opaque && (colorFilter->getFlags() & SkColorFilter::kAlphaUnchanged_Flag);
169 }
170
171 // Not all formats make sense to dither (think, F16). We set their dither rate
172 // to zero. We need to decide if we're going to dither now to keep is_constant accurate.
173 if (paint.isDither()) {
174 switch (dst.info().colorType()) {
175 default: blitter->fDitherRate = 0.0f; break;
176 case kARGB_4444_SkColorType: blitter->fDitherRate = 1/15.0f; break;
177 case kRGB_565_SkColorType: blitter->fDitherRate = 1/63.0f; break;
178 case kGray_8_SkColorType:
179 case kRGB_888x_SkColorType:
180 case kRGBA_8888_SkColorType:
181 case kBGRA_8888_SkColorType: blitter->fDitherRate = 1/255.0f; break;
182 case kRGB_101010x_SkColorType:
183 case kRGBA_1010102_SkColorType: blitter->fDitherRate = 1/1023.0f; break;
184 }
185 // TODO: for constant colors, we could try to measure the effect of dithering, and if
186 // it has no value (i.e. all variations result in the same 32bit color, then we
187 // could disable it (for speed, by not adding the stage).
188 }
189 is_constant = is_constant && (blitter->fDitherRate == 0.0f);
190
191 // We're logically done here. The code between here and return blitter is all optimization.
192
193 // A pipeline that's still constant here can collapse back into a constant color.
194 if (is_constant) {
195 SkPM4f constantColor;
196 SkJumper_MemoryCtx constantColorPtr = { &constantColor, 0 };
197 colorPipeline->append(SkRasterPipeline::store_f32, &constantColorPtr);
198 colorPipeline->run(0,0,1,1);
199 colorPipeline->reset();
200 colorPipeline->append_constant_color(alloc, constantColor);
201
202 is_opaque = constantColor.a() == 1.0f;
203 }
204
205 // We can strength-reduce SrcOver into Src when opaque.
206 if (is_opaque && blitter->fBlend == SkBlendMode::kSrcOver) {
207 blitter->fBlend = SkBlendMode::kSrc;
208 }
209
210 // When we're drawing a constant color in Src mode, we can sometimes just memset.
211 // (The previous two optimizations help find more opportunities for this one.)
212 if (is_constant && blitter->fBlend == SkBlendMode::kSrc) {
213 // Run our color pipeline all the way through to produce what we'd memset when we can.
214 // Not all blits can memset, so we need to keep colorPipeline too.
215 SkRasterPipeline_<256> p;
216 p.extend(*colorPipeline);
217 blitter->fDstPtr = SkJumper_MemoryCtx{&blitter->fMemsetColor, 0};
218 blitter->append_store(&p);
219 p.run(0,0,1,1);
220
221 blitter->fCanMemsetInBlitRect = true;
222 }
223
224 blitter->fDstPtr = SkJumper_MemoryCtx{
225 blitter->fDst.writable_addr(),
226 blitter->fDst.rowBytesAsPixels(),
227 };
228
229 return blitter;
230 }
231
append_load_dst(SkRasterPipeline * p) const232 void SkRasterPipelineBlitter::append_load_dst(SkRasterPipeline* p) const {
233 const void* ctx = &fDstPtr;
234 switch (fDst.info().colorType()) {
235 default: break;
236
237 case kGray_8_SkColorType: p->append(SkRasterPipeline::load_g8_dst, ctx); break;
238 case kAlpha_8_SkColorType: p->append(SkRasterPipeline::load_a8_dst, ctx); break;
239 case kRGB_565_SkColorType: p->append(SkRasterPipeline::load_565_dst, ctx); break;
240 case kARGB_4444_SkColorType: p->append(SkRasterPipeline::load_4444_dst, ctx); break;
241 case kBGRA_8888_SkColorType: p->append(SkRasterPipeline::load_bgra_dst, ctx); break;
242 case kRGBA_8888_SkColorType: p->append(SkRasterPipeline::load_8888_dst, ctx); break;
243 case kRGBA_1010102_SkColorType: p->append(SkRasterPipeline::load_1010102_dst, ctx); break;
244 case kRGBA_F16_SkColorType: p->append(SkRasterPipeline::load_f16_dst, ctx); break;
245
246 case kRGB_888x_SkColorType: p->append(SkRasterPipeline::load_8888_dst, ctx);
247 p->append(SkRasterPipeline::force_opaque_dst ); break;
248 case kRGB_101010x_SkColorType: p->append(SkRasterPipeline::load_1010102_dst, ctx);
249 p->append(SkRasterPipeline::force_opaque_dst ); break;
250 }
251 if (fDst.info().gammaCloseToSRGB()) {
252 p->append(SkRasterPipeline::from_srgb_dst);
253 }
254 if (fDst.info().alphaType() == kUnpremul_SkAlphaType) {
255 p->append(SkRasterPipeline::premul_dst);
256 }
257 }
258
append_store(SkRasterPipeline * p) const259 void SkRasterPipelineBlitter::append_store(SkRasterPipeline* p) const {
260 if (fDst.info().alphaType() == kUnpremul_SkAlphaType) {
261 p->append(SkRasterPipeline::unpremul);
262 }
263 if (fDst.info().gammaCloseToSRGB()) {
264 p->append(SkRasterPipeline::to_srgb);
265 }
266 if (fDitherRate > 0.0f) {
267 // We dither after any sRGB transfer function to make sure our 1/255.0f is sensible
268 // over the whole range. If we did it before, 1/255.0f is too big a rate near zero.
269 p->append(SkRasterPipeline::dither, &fDitherRate);
270 }
271
272 const void* ctx = &fDstPtr;
273 switch (fDst.info().colorType()) {
274 default: break;
275
276 case kGray_8_SkColorType: p->append(SkRasterPipeline::luminance_to_alpha);
277 p->append(SkRasterPipeline::store_a8, ctx); break;
278 case kAlpha_8_SkColorType: p->append(SkRasterPipeline::store_a8, ctx); break;
279 case kRGB_565_SkColorType: p->append(SkRasterPipeline::store_565, ctx); break;
280 case kARGB_4444_SkColorType: p->append(SkRasterPipeline::store_4444, ctx); break;
281 case kBGRA_8888_SkColorType: p->append(SkRasterPipeline::store_bgra, ctx); break;
282 case kRGBA_8888_SkColorType: p->append(SkRasterPipeline::store_8888, ctx); break;
283 case kRGBA_1010102_SkColorType: p->append(SkRasterPipeline::store_1010102, ctx); break;
284 case kRGBA_F16_SkColorType: p->append(SkRasterPipeline::store_f16, ctx); break;
285
286 case kRGB_888x_SkColorType: p->append(SkRasterPipeline::force_opaque );
287 p->append(SkRasterPipeline::store_8888, ctx); break;
288 case kRGB_101010x_SkColorType: p->append(SkRasterPipeline::force_opaque );
289 p->append(SkRasterPipeline::store_1010102, ctx); break;
290 }
291 }
292
burst_shade(int x,int y,int w)293 void SkRasterPipelineBlitter::burst_shade(int x, int y, int w) {
294 SkASSERT(fBurstCtx);
295 if (w > SkToInt(fShaderBuffer.size())) {
296 fShaderBuffer.resize(w);
297 }
298 fBurstCtx->shadeSpan4f(x,y, fShaderBuffer.data(), w);
299 // We'll be reading from fShaderOutput.pixels + x, so back up by x.
300 fShaderOutput = SkJumper_MemoryCtx{ fShaderBuffer.data() - x, 0 };
301 }
302
blitH(int x,int y,int w)303 void SkRasterPipelineBlitter::blitH(int x, int y, int w) {
304 this->blitRect(x,y,w,1);
305 }
306
blitRect(int x,int y,int w,int h)307 void SkRasterPipelineBlitter::blitRect(int x, int y, int w, int h) {
308 if (fCanMemsetInBlitRect) {
309 for (int ylimit = y+h; y < ylimit; y++) {
310 switch (fDst.shiftPerPixel()) {
311 case 0: memset (fDst.writable_addr8 (x,y), fMemsetColor, w); break;
312 case 1: sk_memset16(fDst.writable_addr16(x,y), fMemsetColor, w); break;
313 case 2: sk_memset32(fDst.writable_addr32(x,y), fMemsetColor, w); break;
314 case 3: sk_memset64(fDst.writable_addr64(x,y), fMemsetColor, w); break;
315 default: break;
316 }
317 }
318 return;
319 }
320
321 if (!fBlitRect) {
322 SkRasterPipeline p(fAlloc);
323 p.extend(fColorPipeline);
324 if (fBlend == SkBlendMode::kSrcOver
325 && (fDst.info().colorType() == kRGBA_8888_SkColorType ||
326 fDst.info().colorType() == kBGRA_8888_SkColorType)
327 && !fDst.colorSpace()
328 && fDst.info().alphaType() != kUnpremul_SkAlphaType
329 && fDitherRate == 0.0f) {
330 auto stage = fDst.info().colorType() == kRGBA_8888_SkColorType
331 ? SkRasterPipeline::srcover_rgba_8888
332 : SkRasterPipeline::srcover_bgra_8888;
333 p.append(stage, &fDstPtr);
334 } else {
335 if (fBlend != SkBlendMode::kSrc) {
336 this->append_load_dst(&p);
337 SkBlendMode_AppendStages(fBlend, &p);
338 }
339 this->append_store(&p);
340 }
341 fBlitRect = p.compile();
342 }
343
344 if (fBurstCtx) {
345 // We can only burst shade one row at a time.
346 for (int ylimit = y+h; y < ylimit; y++) {
347 this->burst_shade(x,y,w);
348 fBlitRect(x,y, w,1);
349 }
350 } else {
351 // If not bursting we can blit the entire rect at once.
352 fBlitRect(x,y,w,h);
353 }
354 }
355
blitAntiH(int x,int y,const SkAlpha aa[],const int16_t runs[])356 void SkRasterPipelineBlitter::blitAntiH(int x, int y, const SkAlpha aa[], const int16_t runs[]) {
357 if (!fBlitAntiH) {
358 SkRasterPipeline p(fAlloc);
359 p.extend(fColorPipeline);
360 if (SkBlendMode_ShouldPreScaleCoverage(fBlend, /*rgb_coverage=*/false)) {
361 p.append(SkRasterPipeline::scale_1_float, &fCurrentCoverage);
362 this->append_load_dst(&p);
363 SkBlendMode_AppendStages(fBlend, &p);
364 } else {
365 this->append_load_dst(&p);
366 SkBlendMode_AppendStages(fBlend, &p);
367 p.append(SkRasterPipeline::lerp_1_float, &fCurrentCoverage);
368 }
369
370 this->append_store(&p);
371 fBlitAntiH = p.compile();
372 }
373
374 for (int16_t run = *runs; run > 0; run = *runs) {
375 switch (*aa) {
376 case 0x00: break;
377 case 0xff: this->blitH(x,y,run); break;
378 default:
379 fCurrentCoverage = *aa * (1/255.0f);
380 if (fBurstCtx) {
381 this->burst_shade(x,y,run);
382 }
383 fBlitAntiH(x,y,run,1);
384 }
385 x += run;
386 runs += run;
387 aa += run;
388 }
389 }
390
blitAntiH2(int x,int y,U8CPU a0,U8CPU a1)391 void SkRasterPipelineBlitter::blitAntiH2(int x, int y, U8CPU a0, U8CPU a1) {
392 SkIRect clip = {x,y, x+2,y+1};
393 uint8_t coverage[] = { (uint8_t)a0, (uint8_t)a1 };
394
395 SkMask mask;
396 mask.fImage = coverage;
397 mask.fBounds = clip;
398 mask.fRowBytes = 2;
399 mask.fFormat = SkMask::kA8_Format;
400
401 this->blitMask(mask, clip);
402 }
403
blitAntiV2(int x,int y,U8CPU a0,U8CPU a1)404 void SkRasterPipelineBlitter::blitAntiV2(int x, int y, U8CPU a0, U8CPU a1) {
405 SkIRect clip = {x,y, x+1,y+2};
406 uint8_t coverage[] = { (uint8_t)a0, (uint8_t)a1 };
407
408 SkMask mask;
409 mask.fImage = coverage;
410 mask.fBounds = clip;
411 mask.fRowBytes = 1;
412 mask.fFormat = SkMask::kA8_Format;
413
414 this->blitMask(mask, clip);
415 }
416
blitV(int x,int y,int height,SkAlpha alpha)417 void SkRasterPipelineBlitter::blitV(int x, int y, int height, SkAlpha alpha) {
418 SkIRect clip = {x,y, x+1,y+height};
419
420 SkMask mask;
421 mask.fImage = α
422 mask.fBounds = clip;
423 mask.fRowBytes = 0; // so we reuse the 1 "row" for all of height
424 mask.fFormat = SkMask::kA8_Format;
425
426 this->blitMask(mask, clip);
427 }
428
blitMask(const SkMask & mask,const SkIRect & clip)429 void SkRasterPipelineBlitter::blitMask(const SkMask& mask, const SkIRect& clip) {
430 if (mask.fFormat == SkMask::kBW_Format) {
431 // TODO: native BW masks?
432 return INHERITED::blitMask(mask, clip);
433 }
434
435 // We'll use the first (A8) plane of any mask and ignore the other two, just like Ganesh.
436 SkMask::Format effectiveMaskFormat = mask.fFormat == SkMask::k3D_Format ? SkMask::kA8_Format
437 : mask.fFormat;
438
439
440 // Lazily build whichever pipeline we need, specialized for each mask format.
441 if (effectiveMaskFormat == SkMask::kA8_Format && !fBlitMaskA8) {
442 SkRasterPipeline p(fAlloc);
443 p.extend(fColorPipeline);
444 if (SkBlendMode_ShouldPreScaleCoverage(fBlend, /*rgb_coverage=*/false)) {
445 p.append(SkRasterPipeline::scale_u8, &fMaskPtr);
446 this->append_load_dst(&p);
447 SkBlendMode_AppendStages(fBlend, &p);
448 } else {
449 this->append_load_dst(&p);
450 SkBlendMode_AppendStages(fBlend, &p);
451 p.append(SkRasterPipeline::lerp_u8, &fMaskPtr);
452 }
453 this->append_store(&p);
454 fBlitMaskA8 = p.compile();
455 }
456 if (effectiveMaskFormat == SkMask::kLCD16_Format && !fBlitMaskLCD16) {
457 SkRasterPipeline p(fAlloc);
458 p.extend(fColorPipeline);
459 if (SkBlendMode_ShouldPreScaleCoverage(fBlend, /*rgb_coverage=*/true)) {
460 // Somewhat unusually, scale_565 needs dst loaded first.
461 this->append_load_dst(&p);
462 p.append(SkRasterPipeline::scale_565, &fMaskPtr);
463 SkBlendMode_AppendStages(fBlend, &p);
464 } else {
465 this->append_load_dst(&p);
466 SkBlendMode_AppendStages(fBlend, &p);
467 p.append(SkRasterPipeline::lerp_565, &fMaskPtr);
468 }
469 this->append_store(&p);
470 fBlitMaskLCD16 = p.compile();
471 }
472
473 std::function<void(size_t,size_t,size_t,size_t)>* blitter = nullptr;
474 // Update fMaskPtr to point "into" this current mask, but lined up with fDstPtr at (0,0).
475 switch (effectiveMaskFormat) {
476 case SkMask::kA8_Format:
477 fMaskPtr.stride = mask.fRowBytes;
478 fMaskPtr.pixels = (uint8_t*)mask.fImage - mask.fBounds.left()
479 - mask.fBounds.top() * fMaskPtr.stride;
480 blitter = &fBlitMaskA8;
481 break;
482 case SkMask::kLCD16_Format:
483 fMaskPtr.stride = mask.fRowBytes / 2;
484 fMaskPtr.pixels = (uint16_t*)mask.fImage - mask.fBounds.left()
485 - mask.fBounds.top() * fMaskPtr.stride;
486 blitter = &fBlitMaskLCD16;
487 break;
488 default:
489 return;
490 }
491
492 SkASSERT(blitter);
493 if (fBurstCtx) {
494 // We can only burst shade one row at a time.
495 int x = clip.left();
496 for (int y = clip.top(); y < clip.bottom(); y++) {
497 this->burst_shade(x,y,clip.width());
498 (*blitter)(x,y, clip.width(),1);
499 }
500 } else {
501 // If not bursting we can blit the entire mask at once.
502 (*blitter)(clip.left(),clip.top(), clip.width(),clip.height());
503 }
504 }
505