1 /*
2 * Copyright 2006 The Android Open Source Project
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 "src/core/SkBlitter.h"
9
10 #include "include/core/SkColor.h"
11 #include "include/core/SkColorFilter.h"
12 #include "include/core/SkString.h"
13 #include "include/private/SkColorData.h"
14 #include "include/private/SkTo.h"
15 #include "src/core/SkAntiRun.h"
16 #include "src/core/SkArenaAlloc.h"
17 #include "src/core/SkMask.h"
18 #include "src/core/SkMaskFilterBase.h"
19 #include "src/core/SkMatrixProvider.h"
20 #include "src/core/SkOpts.h"
21 #include "src/core/SkPaintPriv.h"
22 #include "src/core/SkReadBuffer.h"
23 #include "src/core/SkRegionPriv.h"
24 #include "src/core/SkTLazy.h"
25 #include "src/core/SkVMBlitter.h"
26 #include "src/core/SkWriteBuffer.h"
27 #include "src/core/SkXfermodeInterpretation.h"
28 #include "src/shaders/SkShaderBase.h"
29
30 // Hacks for testing.
31 bool gUseSkVMBlitter{false};
32 bool gSkForceRasterPipelineBlitter{false};
33
~SkBlitter()34 SkBlitter::~SkBlitter() {}
35
isNullBlitter() const36 bool SkBlitter::isNullBlitter() const { return false; }
37
justAnOpaqueColor(uint32_t * value)38 const SkPixmap* SkBlitter::justAnOpaqueColor(uint32_t* value) {
39 return nullptr;
40 }
41
42 /*
43 void SkBlitter::blitH(int x, int y, int width) {
44 SkDEBUGFAIL("unimplemented");
45 }
46
47
48 void SkBlitter::blitAntiH(int x, int y, const SkAlpha antialias[],
49 const int16_t runs[]) {
50 SkDEBUGFAIL("unimplemented");
51 }
52 */
53
ScalarToAlpha(SkScalar a)54 inline static SkAlpha ScalarToAlpha(SkScalar a) {
55 SkAlpha alpha = (SkAlpha)(a * 255);
56 return alpha > 247 ? 0xFF : alpha < 8 ? 0 : alpha;
57 }
58
blitFatAntiRect(const SkRect & rect)59 void SkBlitter::blitFatAntiRect(const SkRect& rect) {
60 SkIRect bounds = rect.roundOut();
61 SkASSERT(bounds.width() >= 3);
62
63 // skbug.com/7813
64 // To ensure consistency of the threaded backend (a rect that's considered fat in the init-once
65 // phase must also be considered fat in the draw phase), we have to deal with rects with small
66 // heights because the horizontal tiling in the threaded backend may change the height.
67 //
68 // This also implies that we cannot do vertical tiling unless we can blit any rect (not just the
69 // fat one.)
70 if (bounds.height() == 0) {
71 return;
72 }
73
74 int runSize = bounds.width() + 1; // +1 so we can set runs[bounds.width()] = 0
75 void* storage = this->allocBlitMemory(runSize * (sizeof(int16_t) + sizeof(SkAlpha)));
76 int16_t* runs = reinterpret_cast<int16_t*>(storage);
77 SkAlpha* alphas = reinterpret_cast<SkAlpha*>(runs + runSize);
78
79 runs[0] = 1;
80 runs[1] = bounds.width() - 2;
81 runs[bounds.width() - 1] = 1;
82 runs[bounds.width()] = 0;
83
84 SkScalar partialL = bounds.fLeft + 1 - rect.fLeft;
85 SkScalar partialR = rect.fRight - (bounds.fRight - 1);
86 SkScalar partialT = bounds.fTop + 1 - rect.fTop;
87 SkScalar partialB = rect.fBottom - (bounds.fBottom - 1);
88
89 if (bounds.height() == 1) {
90 partialT = rect.fBottom - rect.fTop;
91 }
92
93 alphas[0] = ScalarToAlpha(partialL * partialT);
94 alphas[1] = ScalarToAlpha(partialT);
95 alphas[bounds.width() - 1] = ScalarToAlpha(partialR * partialT);
96 this->blitAntiH(bounds.fLeft, bounds.fTop, alphas, runs);
97
98 if (bounds.height() > 2) {
99 this->blitAntiRect(bounds.fLeft, bounds.fTop + 1, bounds.width() - 2, bounds.height() - 2,
100 ScalarToAlpha(partialL), ScalarToAlpha(partialR));
101 }
102
103 if (bounds.height() > 1) {
104 alphas[0] = ScalarToAlpha(partialL * partialB);
105 alphas[1] = ScalarToAlpha(partialB);
106 alphas[bounds.width() - 1] = ScalarToAlpha(partialR * partialB);
107 this->blitAntiH(bounds.fLeft, bounds.fBottom - 1, alphas, runs);
108 }
109 }
110
blitV(int x,int y,int height,SkAlpha alpha)111 void SkBlitter::blitV(int x, int y, int height, SkAlpha alpha) {
112 if (alpha == 255) {
113 this->blitRect(x, y, 1, height);
114 } else {
115 int16_t runs[2];
116 runs[0] = 1;
117 runs[1] = 0;
118
119 while (--height >= 0) {
120 this->blitAntiH(x, y++, &alpha, runs);
121 }
122 }
123 }
124
blitRect(int x,int y,int width,int height)125 void SkBlitter::blitRect(int x, int y, int width, int height) {
126 SkASSERT(width > 0);
127 while (--height >= 0) {
128 this->blitH(x, y++, width);
129 }
130 }
131
132 /// Default implementation doesn't check for easy optimizations
133 /// such as alpha == 255; also uses blitV(), which some subclasses
134 /// may not support.
blitAntiRect(int x,int y,int width,int height,SkAlpha leftAlpha,SkAlpha rightAlpha)135 void SkBlitter::blitAntiRect(int x, int y, int width, int height,
136 SkAlpha leftAlpha, SkAlpha rightAlpha) {
137 if (leftAlpha > 0) { // we may send in x = -1 with leftAlpha = 0
138 this->blitV(x, y, height, leftAlpha);
139 }
140 x++;
141 if (width > 0) {
142 this->blitRect(x, y, width, height);
143 x += width;
144 }
145 if (rightAlpha > 0) {
146 this->blitV(x, y, height, rightAlpha);
147 }
148 }
149
150 //////////////////////////////////////////////////////////////////////////////
151
bits_to_runs(SkBlitter * blitter,int x,int y,const uint8_t bits[],uint8_t left_mask,ptrdiff_t rowBytes,uint8_t right_mask)152 static inline void bits_to_runs(SkBlitter* blitter, int x, int y,
153 const uint8_t bits[],
154 uint8_t left_mask, ptrdiff_t rowBytes,
155 uint8_t right_mask) {
156 int inFill = 0;
157 int pos = 0;
158
159 while (--rowBytes >= 0) {
160 uint8_t b = *bits++ & left_mask;
161 if (rowBytes == 0) {
162 b &= right_mask;
163 }
164
165 for (uint8_t test = 0x80U; test != 0; test >>= 1) {
166 if (b & test) {
167 if (!inFill) {
168 pos = x;
169 inFill = true;
170 }
171 } else {
172 if (inFill) {
173 blitter->blitH(pos, y, x - pos);
174 inFill = false;
175 }
176 }
177 x += 1;
178 }
179 left_mask = 0xFFU;
180 }
181
182 // final cleanup
183 if (inFill) {
184 blitter->blitH(pos, y, x - pos);
185 }
186 }
187
188 // maskBitCount is the number of 1's to place in the mask. It must be in the range between 1 and 8.
generate_right_mask(int maskBitCount)189 static uint8_t generate_right_mask(int maskBitCount) {
190 return static_cast<uint8_t>((0xFF00U >> maskBitCount) & 0xFF);
191 }
192
blitMask(const SkMask & mask,const SkIRect & clip)193 void SkBlitter::blitMask(const SkMask& mask, const SkIRect& clip) {
194 SkASSERT(mask.fBounds.contains(clip));
195
196 if (mask.fFormat == SkMask::kLCD16_Format) {
197 return; // needs to be handled by subclass
198 }
199
200 if (mask.fFormat == SkMask::kBW_Format) {
201 int cx = clip.fLeft;
202 int cy = clip.fTop;
203 int maskLeft = mask.fBounds.fLeft;
204 int maskRowBytes = mask.fRowBytes;
205 int height = clip.height();
206
207 const uint8_t* bits = mask.getAddr1(cx, cy);
208
209 SkDEBUGCODE(const uint8_t* endOfImage =
210 mask.fImage + (mask.fBounds.height() - 1) * maskRowBytes
211 + ((mask.fBounds.width() + 7) >> 3));
212
213 if (cx == maskLeft && clip.fRight == mask.fBounds.fRight) {
214 while (--height >= 0) {
215 int affectedRightBit = mask.fBounds.width() - 1;
216 ptrdiff_t rowBytes = (affectedRightBit >> 3) + 1;
217 SkASSERT(bits + rowBytes <= endOfImage);
218 U8CPU rightMask = generate_right_mask((affectedRightBit & 7) + 1);
219 bits_to_runs(this, cx, cy, bits, 0xFF, rowBytes, rightMask);
220 bits += maskRowBytes;
221 cy += 1;
222 }
223 } else {
224 // Bits is calculated as the offset into the mask at the point {cx, cy} therefore, all
225 // addressing into the bit mask is relative to that point. Since this is an address
226 // calculated from a arbitrary bit in that byte, calculate the left most bit.
227 int bitsLeft = cx - ((cx - maskLeft) & 7);
228
229 // Everything is relative to the bitsLeft.
230 int leftEdge = cx - bitsLeft;
231 SkASSERT(leftEdge >= 0);
232 int rightEdge = clip.fRight - bitsLeft;
233 SkASSERT(rightEdge > leftEdge);
234
235 // Calculate left byte and mask
236 const uint8_t* leftByte = bits;
237 U8CPU leftMask = 0xFFU >> (leftEdge & 7);
238
239 // Calculate right byte and mask
240 int affectedRightBit = rightEdge - 1;
241 const uint8_t* rightByte = bits + (affectedRightBit >> 3);
242 U8CPU rightMask = generate_right_mask((affectedRightBit & 7) + 1);
243
244 // leftByte and rightByte are byte locations therefore, to get a count of bytes the
245 // code must add one.
246 ptrdiff_t rowBytes = rightByte - leftByte + 1;
247
248 while (--height >= 0) {
249 SkASSERT(bits + rowBytes <= endOfImage);
250 bits_to_runs(this, bitsLeft, cy, bits, leftMask, rowBytes, rightMask);
251 bits += maskRowBytes;
252 cy += 1;
253 }
254 }
255 } else {
256 int width = clip.width();
257 SkAutoSTMalloc<64, int16_t> runStorage(width + 1);
258 int16_t* runs = runStorage.get();
259 const uint8_t* aa = mask.getAddr8(clip.fLeft, clip.fTop);
260
261 sk_memset16((uint16_t*)runs, 1, width);
262 runs[width] = 0;
263
264 int height = clip.height();
265 int y = clip.fTop;
266 while (--height >= 0) {
267 this->blitAntiH(clip.fLeft, y, aa, runs);
268 aa += mask.fRowBytes;
269 y += 1;
270 }
271 }
272 }
273
274 /////////////////////// these are not virtual, just helpers
275
blitMaskRegion(const SkMask & mask,const SkRegion & clip)276 void SkBlitter::blitMaskRegion(const SkMask& mask, const SkRegion& clip) {
277 if (clip.quickReject(mask.fBounds)) {
278 return;
279 }
280
281 SkRegion::Cliperator clipper(clip, mask.fBounds);
282
283 while (!clipper.done()) {
284 const SkIRect& cr = clipper.rect();
285 this->blitMask(mask, cr);
286 clipper.next();
287 }
288 }
289
blitRectRegion(const SkIRect & rect,const SkRegion & clip)290 void SkBlitter::blitRectRegion(const SkIRect& rect, const SkRegion& clip) {
291 SkRegion::Cliperator clipper(clip, rect);
292
293 while (!clipper.done()) {
294 const SkIRect& cr = clipper.rect();
295 this->blitRect(cr.fLeft, cr.fTop, cr.width(), cr.height());
296 clipper.next();
297 }
298 }
299
blitRegion(const SkRegion & clip)300 void SkBlitter::blitRegion(const SkRegion& clip) {
301 SkRegionPriv::VisitSpans(clip, [this](const SkIRect& r) {
302 this->blitRect(r.left(), r.top(), r.width(), r.height());
303 });
304 }
305
306 ///////////////////////////////////////////////////////////////////////////////
307
blitH(int x,int y,int width)308 void SkNullBlitter::blitH(int x, int y, int width) {}
309
blitAntiH(int x,int y,const SkAlpha antialias[],const int16_t runs[])310 void SkNullBlitter::blitAntiH(int x, int y, const SkAlpha antialias[],
311 const int16_t runs[]) {}
312
blitV(int x,int y,int height,SkAlpha alpha)313 void SkNullBlitter::blitV(int x, int y, int height, SkAlpha alpha) {}
314
blitRect(int x,int y,int width,int height)315 void SkNullBlitter::blitRect(int x, int y, int width, int height) {}
316
blitMask(const SkMask & mask,const SkIRect & clip)317 void SkNullBlitter::blitMask(const SkMask& mask, const SkIRect& clip) {}
318
justAnOpaqueColor(uint32_t * value)319 const SkPixmap* SkNullBlitter::justAnOpaqueColor(uint32_t* value) {
320 return nullptr;
321 }
322
isNullBlitter() const323 bool SkNullBlitter::isNullBlitter() const { return true; }
324
325 ///////////////////////////////////////////////////////////////////////////////
326
compute_anti_width(const int16_t runs[])327 static int compute_anti_width(const int16_t runs[]) {
328 int width = 0;
329
330 for (;;) {
331 int count = runs[0];
332
333 SkASSERT(count >= 0);
334 if (count == 0) {
335 break;
336 }
337 width += count;
338 runs += count;
339 }
340 return width;
341 }
342
y_in_rect(int y,const SkIRect & rect)343 static inline bool y_in_rect(int y, const SkIRect& rect) {
344 return (unsigned)(y - rect.fTop) < (unsigned)rect.height();
345 }
346
x_in_rect(int x,const SkIRect & rect)347 static inline bool x_in_rect(int x, const SkIRect& rect) {
348 return (unsigned)(x - rect.fLeft) < (unsigned)rect.width();
349 }
350
blitH(int left,int y,int width)351 void SkRectClipBlitter::blitH(int left, int y, int width) {
352 SkASSERT(width > 0);
353
354 if (!y_in_rect(y, fClipRect)) {
355 return;
356 }
357
358 int right = left + width;
359
360 if (left < fClipRect.fLeft) {
361 left = fClipRect.fLeft;
362 }
363 if (right > fClipRect.fRight) {
364 right = fClipRect.fRight;
365 }
366
367 width = right - left;
368 if (width > 0) {
369 fBlitter->blitH(left, y, width);
370 }
371 }
372
blitAntiH(int left,int y,const SkAlpha aa[],const int16_t runs[])373 void SkRectClipBlitter::blitAntiH(int left, int y, const SkAlpha aa[],
374 const int16_t runs[]) {
375 if (!y_in_rect(y, fClipRect) || left >= fClipRect.fRight) {
376 return;
377 }
378
379 int x0 = left;
380 int x1 = left + compute_anti_width(runs);
381
382 if (x1 <= fClipRect.fLeft) {
383 return;
384 }
385
386 SkASSERT(x0 < x1);
387 if (x0 < fClipRect.fLeft) {
388 int dx = fClipRect.fLeft - x0;
389 SkAlphaRuns::BreakAt((int16_t*)runs, (uint8_t*)aa, dx);
390 runs += dx;
391 aa += dx;
392 x0 = fClipRect.fLeft;
393 }
394
395 SkASSERT(x0 < x1 && runs[x1 - x0] == 0);
396 if (x1 > fClipRect.fRight) {
397 x1 = fClipRect.fRight;
398 SkAlphaRuns::BreakAt((int16_t*)runs, (uint8_t*)aa, x1 - x0);
399 ((int16_t*)runs)[x1 - x0] = 0;
400 }
401
402 SkASSERT(x0 < x1 && runs[x1 - x0] == 0);
403 SkASSERT(compute_anti_width(runs) == x1 - x0);
404
405 fBlitter->blitAntiH(x0, y, aa, runs);
406 }
407
blitV(int x,int y,int height,SkAlpha alpha)408 void SkRectClipBlitter::blitV(int x, int y, int height, SkAlpha alpha) {
409 SkASSERT(height > 0);
410
411 if (!x_in_rect(x, fClipRect)) {
412 return;
413 }
414
415 int y0 = y;
416 int y1 = y + height;
417
418 if (y0 < fClipRect.fTop) {
419 y0 = fClipRect.fTop;
420 }
421 if (y1 > fClipRect.fBottom) {
422 y1 = fClipRect.fBottom;
423 }
424
425 if (y0 < y1) {
426 fBlitter->blitV(x, y0, y1 - y0, alpha);
427 }
428 }
429
blitRect(int left,int y,int width,int height)430 void SkRectClipBlitter::blitRect(int left, int y, int width, int height) {
431 SkIRect r;
432
433 r.setLTRB(left, y, left + width, y + height);
434 if (r.intersect(fClipRect)) {
435 fBlitter->blitRect(r.fLeft, r.fTop, r.width(), r.height());
436 }
437 }
438
blitAntiRect(int left,int y,int width,int height,SkAlpha leftAlpha,SkAlpha rightAlpha)439 void SkRectClipBlitter::blitAntiRect(int left, int y, int width, int height,
440 SkAlpha leftAlpha, SkAlpha rightAlpha) {
441 SkIRect r;
442
443 // The *true* width of the rectangle blitted is width+2:
444 r.setLTRB(left, y, left + width + 2, y + height);
445 if (r.intersect(fClipRect)) {
446 if (r.fLeft != left) {
447 SkASSERT(r.fLeft > left);
448 leftAlpha = 255;
449 }
450 if (r.fRight != left + width + 2) {
451 SkASSERT(r.fRight < left + width + 2);
452 rightAlpha = 255;
453 }
454 if (255 == leftAlpha && 255 == rightAlpha) {
455 fBlitter->blitRect(r.fLeft, r.fTop, r.width(), r.height());
456 } else if (1 == r.width()) {
457 if (r.fLeft == left) {
458 fBlitter->blitV(r.fLeft, r.fTop, r.height(), leftAlpha);
459 } else {
460 SkASSERT(r.fLeft == left + width + 1);
461 fBlitter->blitV(r.fLeft, r.fTop, r.height(), rightAlpha);
462 }
463 } else {
464 fBlitter->blitAntiRect(r.fLeft, r.fTop, r.width() - 2, r.height(),
465 leftAlpha, rightAlpha);
466 }
467 }
468 }
469
blitMask(const SkMask & mask,const SkIRect & clip)470 void SkRectClipBlitter::blitMask(const SkMask& mask, const SkIRect& clip) {
471 SkASSERT(mask.fBounds.contains(clip));
472
473 SkIRect r = clip;
474
475 if (r.intersect(fClipRect)) {
476 fBlitter->blitMask(mask, r);
477 }
478 }
479
justAnOpaqueColor(uint32_t * value)480 const SkPixmap* SkRectClipBlitter::justAnOpaqueColor(uint32_t* value) {
481 return fBlitter->justAnOpaqueColor(value);
482 }
483
484 ///////////////////////////////////////////////////////////////////////////////
485
blitH(int x,int y,int width)486 void SkRgnClipBlitter::blitH(int x, int y, int width) {
487 SkRegion::Spanerator span(*fRgn, y, x, x + width);
488 int left, right;
489
490 while (span.next(&left, &right)) {
491 SkASSERT(left < right);
492 fBlitter->blitH(left, y, right - left);
493 }
494 }
495
blitAntiH(int x,int y,const SkAlpha aa[],const int16_t runs[])496 void SkRgnClipBlitter::blitAntiH(int x, int y, const SkAlpha aa[],
497 const int16_t runs[]) {
498 int width = compute_anti_width(runs);
499 SkRegion::Spanerator span(*fRgn, y, x, x + width);
500 int left, right;
501 SkDEBUGCODE(const SkIRect& bounds = fRgn->getBounds();)
502
503 int prevRite = x;
504 while (span.next(&left, &right)) {
505 SkASSERT(x <= left);
506 SkASSERT(left < right);
507 SkASSERT(left >= bounds.fLeft && right <= bounds.fRight);
508
509 SkAlphaRuns::Break((int16_t*)runs, (uint8_t*)aa, left - x, right - left);
510
511 // now zero before left
512 if (left > prevRite) {
513 int index = prevRite - x;
514 ((uint8_t*)aa)[index] = 0; // skip runs after right
515 ((int16_t*)runs)[index] = SkToS16(left - prevRite);
516 }
517
518 prevRite = right;
519 }
520
521 if (prevRite > x) {
522 ((int16_t*)runs)[prevRite - x] = 0;
523
524 if (x < 0) {
525 int skip = runs[0];
526 SkASSERT(skip >= -x);
527 aa += skip;
528 runs += skip;
529 x += skip;
530 }
531 fBlitter->blitAntiH(x, y, aa, runs);
532 }
533 }
534
blitV(int x,int y,int height,SkAlpha alpha)535 void SkRgnClipBlitter::blitV(int x, int y, int height, SkAlpha alpha) {
536 SkIRect bounds;
537 bounds.setXYWH(x, y, 1, height);
538
539 SkRegion::Cliperator iter(*fRgn, bounds);
540
541 while (!iter.done()) {
542 const SkIRect& r = iter.rect();
543 SkASSERT(bounds.contains(r));
544
545 fBlitter->blitV(x, r.fTop, r.height(), alpha);
546 iter.next();
547 }
548 }
549
blitRect(int x,int y,int width,int height)550 void SkRgnClipBlitter::blitRect(int x, int y, int width, int height) {
551 SkIRect bounds;
552 bounds.setXYWH(x, y, width, height);
553
554 SkRegion::Cliperator iter(*fRgn, bounds);
555
556 while (!iter.done()) {
557 const SkIRect& r = iter.rect();
558 SkASSERT(bounds.contains(r));
559
560 fBlitter->blitRect(r.fLeft, r.fTop, r.width(), r.height());
561 iter.next();
562 }
563 }
564
blitAntiRect(int x,int y,int width,int height,SkAlpha leftAlpha,SkAlpha rightAlpha)565 void SkRgnClipBlitter::blitAntiRect(int x, int y, int width, int height,
566 SkAlpha leftAlpha, SkAlpha rightAlpha) {
567 // The *true* width of the rectangle to blit is width + 2
568 SkIRect bounds;
569 bounds.setXYWH(x, y, width + 2, height);
570
571 SkRegion::Cliperator iter(*fRgn, bounds);
572
573 while (!iter.done()) {
574 const SkIRect& r = iter.rect();
575 SkASSERT(bounds.contains(r));
576 SkASSERT(r.fLeft >= x);
577 SkASSERT(r.fRight <= x + width + 2);
578
579 SkAlpha effectiveLeftAlpha = (r.fLeft == x) ? leftAlpha : 255;
580 SkAlpha effectiveRightAlpha = (r.fRight == x + width + 2) ?
581 rightAlpha : 255;
582
583 if (255 == effectiveLeftAlpha && 255 == effectiveRightAlpha) {
584 fBlitter->blitRect(r.fLeft, r.fTop, r.width(), r.height());
585 } else if (1 == r.width()) {
586 if (r.fLeft == x) {
587 fBlitter->blitV(r.fLeft, r.fTop, r.height(),
588 effectiveLeftAlpha);
589 } else {
590 SkASSERT(r.fLeft == x + width + 1);
591 fBlitter->blitV(r.fLeft, r.fTop, r.height(),
592 effectiveRightAlpha);
593 }
594 } else {
595 fBlitter->blitAntiRect(r.fLeft, r.fTop, r.width() - 2, r.height(),
596 effectiveLeftAlpha, effectiveRightAlpha);
597 }
598 iter.next();
599 }
600 }
601
602
blitMask(const SkMask & mask,const SkIRect & clip)603 void SkRgnClipBlitter::blitMask(const SkMask& mask, const SkIRect& clip) {
604 SkASSERT(mask.fBounds.contains(clip));
605
606 SkRegion::Cliperator iter(*fRgn, clip);
607 const SkIRect& r = iter.rect();
608 SkBlitter* blitter = fBlitter;
609
610 while (!iter.done()) {
611 blitter->blitMask(mask, r);
612 iter.next();
613 }
614 }
615
justAnOpaqueColor(uint32_t * value)616 const SkPixmap* SkRgnClipBlitter::justAnOpaqueColor(uint32_t* value) {
617 return fBlitter->justAnOpaqueColor(value);
618 }
619
620 ///////////////////////////////////////////////////////////////////////////////
621
apply(SkBlitter * blitter,const SkRegion * clip,const SkIRect * ir)622 SkBlitter* SkBlitterClipper::apply(SkBlitter* blitter, const SkRegion* clip,
623 const SkIRect* ir) {
624 if (clip) {
625 const SkIRect& clipR = clip->getBounds();
626
627 if (clip->isEmpty() || (ir && !SkIRect::Intersects(clipR, *ir))) {
628 blitter = &fNullBlitter;
629 } else if (clip->isRect()) {
630 if (ir == nullptr || !clipR.contains(*ir)) {
631 fRectBlitter.init(blitter, clipR);
632 blitter = &fRectBlitter;
633 }
634 } else {
635 fRgnBlitter.init(blitter, clip);
636 blitter = &fRgnBlitter;
637 }
638 }
639 return blitter;
640 }
641
642 ///////////////////////////////////////////////////////////////////////////////
643
644 #include "src/core/SkCoreBlitters.h"
645
UseLegacyBlitter(const SkPixmap & device,const SkPaint & paint,const SkMatrix & matrix)646 bool SkBlitter::UseLegacyBlitter(const SkPixmap& device,
647 const SkPaint& paint,
648 const SkMatrix& matrix) {
649 if (gSkForceRasterPipelineBlitter) {
650 return false;
651 }
652 #if defined(SK_FORCE_RASTER_PIPELINE_BLITTER)
653 return false;
654 #else
655
656 #if !defined(SK_SUPPORT_LEGACY_DITHER)
657 if (paint.isDither()) {
658 return false;
659 }
660 #endif
661
662 const SkMaskFilterBase* mf = as_MFB(paint.getMaskFilter());
663 const auto mode = paint.asBlendMode();
664
665 // The legacy blitters cannot handle any of these complex features (anymore).
666 if (device.alphaType() == kUnpremul_SkAlphaType ||
667 !mode ||
668 mode.value() > SkBlendMode::kLastCoeffMode ||
669 (mf && mf->getFormat() == SkMask::k3D_Format)) {
670 return false;
671 }
672
673 // All the real legacy fast paths are for shaders and SrcOver.
674 // Choosing SkRasterPipelineBlitter will also let us to hit its single-color memset path.
675 if (!paint.getShader() && mode != SkBlendMode::kSrcOver) {
676 return false;
677 }
678
679 auto cs = device.colorSpace();
680 // We check (indirectly via makeContext()) later on if the shader can handle the colorspace
681 // in legacy mode, so here we just focus on if a single color needs raster-pipeline.
682 if (cs && !paint.getShader()) {
683 if (!paint.getColor4f().fitsInBytes() || !cs->isSRGB()) {
684 return false;
685 }
686 }
687
688 // Only kN32 and 565 are handled by legacy blitters now, 565 mostly just for Android.
689 return device.colorType() == kN32_SkColorType
690 || device.colorType() == kRGB_565_SkColorType;
691 #endif
692 }
693
Choose(const SkPixmap & device,const SkMatrixProvider & matrixProvider,const SkPaint & origPaint,SkArenaAlloc * alloc,bool drawCoverage,sk_sp<SkShader> clipShader)694 SkBlitter* SkBlitter::Choose(const SkPixmap& device,
695 const SkMatrixProvider& matrixProvider,
696 const SkPaint& origPaint,
697 SkArenaAlloc* alloc,
698 bool drawCoverage,
699 sk_sp<SkShader> clipShader) {
700 SkASSERT(alloc);
701
702 if (kUnknown_SkColorType == device.colorType()) {
703 return alloc->make<SkNullBlitter>();
704 }
705
706 // We may tweak the original paint as we go.
707 SkTCopyOnFirstWrite<SkPaint> paint(origPaint);
708
709 if (auto mode = paint->asBlendMode()) {
710 // We have the most fast-paths for SrcOver, so see if we can act like SrcOver.
711 if (mode.value() != SkBlendMode::kSrcOver) {
712 switch (SkInterpretXfermode(*paint, SkColorTypeIsAlwaysOpaque(device.colorType()))) {
713 case kSrcOver_SkXfermodeInterpretation:
714 paint.writable()->setBlendMode(SkBlendMode::kSrcOver);
715 break;
716 case kSkipDrawing_SkXfermodeInterpretation:
717 return alloc->make<SkNullBlitter>();
718 default:
719 break;
720 }
721 }
722
723 // A Clear blend mode will ignore the entire color pipeline, as if Src mode with 0x00000000.
724 if (mode.value() == SkBlendMode::kClear) {
725 SkPaint* p = paint.writable();
726 p->setShader(nullptr);
727 p->setColorFilter(nullptr);
728 p->setBlendMode(SkBlendMode::kSrc);
729 p->setColor(0x00000000);
730 }
731 }
732
733 if (paint->getColorFilter()) {
734 SkPaintPriv::RemoveColorFilter(paint.writable(), device.colorSpace());
735 }
736 SkASSERT(!paint->getColorFilter());
737
738 if (drawCoverage) {
739 if (device.colorType() == kAlpha_8_SkColorType) {
740 SkASSERT(!paint->getShader());
741 SkASSERT(paint->isSrcOver());
742 return alloc->make<SkA8_Coverage_Blitter>(device, *paint);
743 }
744 return alloc->make<SkNullBlitter>();
745 }
746
747 if (paint->isDither() && !SkPaintPriv::ShouldDither(*paint, device.colorType())) {
748 paint.writable()->setDither(false);
749 }
750
751 if (gUseSkVMBlitter) {
752 if (auto blitter = SkVMBlitter::Make(device, *paint, matrixProvider,
753 alloc, clipShader)) {
754 return blitter;
755 }
756 }
757
758 // Same basic idea used a few times: try SkRP, then try SkVM, then give up with a null-blitter.
759 // (Setting gUseSkVMBlitter is the only way we prefer SkVM over SkRP at the moment.)
760 auto create_SkRP_or_SkVMBlitter = [&]() -> SkBlitter* {
761 if (auto blitter = SkCreateRasterPipelineBlitter(device, *paint, matrixProvider,
762 alloc, clipShader)) {
763 return blitter;
764 }
765 if (auto blitter = SkVMBlitter::Make(device, *paint, matrixProvider,
766 alloc, clipShader)) {
767 return blitter;
768 }
769 return alloc->make<SkNullBlitter>();
770 };
771
772 SkMatrix ctm = matrixProvider.localToDevice();
773 // We'll end here for many interesting cases: color spaces, color filters, most color types.
774 if (clipShader || !UseLegacyBlitter(device, *paint, ctm)) {
775 return create_SkRP_or_SkVMBlitter();
776 }
777
778 // Everything but legacy kN32_SkColorType and kRGB_565_SkColorType should already be handled.
779 SkASSERT(device.colorType() == kN32_SkColorType ||
780 device.colorType() == kRGB_565_SkColorType);
781
782 // And we should either have a shader, be blending with SrcOver, or both.
783 SkASSERT(paint->getShader() || paint->asBlendMode() == SkBlendMode::kSrcOver);
784
785 // Legacy blitters keep their shader state on a shader context.
786 SkShaderBase::Context* shaderContext = nullptr;
787 if (paint->getShader()) {
788 shaderContext = as_SB(paint->getShader())->makeContext(
789 {*paint, ctm, nullptr, device.colorType(), device.colorSpace()},
790 alloc);
791
792 // Creating the context isn't always possible... try fallbacks before giving up.
793 if (!shaderContext) {
794 return create_SkRP_or_SkVMBlitter();
795 }
796 }
797
798 switch (device.colorType()) {
799 case kN32_SkColorType:
800 if (shaderContext) {
801 return alloc->make<SkARGB32_Shader_Blitter>(device, *paint, shaderContext);
802 } else if (paint->getColor() == SK_ColorBLACK) {
803 return alloc->make<SkARGB32_Black_Blitter>(device, *paint);
804 } else if (paint->getAlpha() == 0xFF) {
805 return alloc->make<SkARGB32_Opaque_Blitter>(device, *paint);
806 } else {
807 return alloc->make<SkARGB32_Blitter>(device, *paint);
808 }
809
810 case kRGB_565_SkColorType:
811 if (shaderContext && SkRGB565_Shader_Blitter::Supports(device, *paint)) {
812 return alloc->make<SkRGB565_Shader_Blitter>(device, *paint, shaderContext);
813 } else {
814 return create_SkRP_or_SkVMBlitter();
815 }
816
817 default:
818 SkASSERT(false);
819 return alloc->make<SkNullBlitter>();
820 }
821 }
822
823 ///////////////////////////////////////////////////////////////////////////////
824
SkShaderBlitter(const SkPixmap & device,const SkPaint & paint,SkShaderBase::Context * shaderContext)825 SkShaderBlitter::SkShaderBlitter(const SkPixmap& device, const SkPaint& paint,
826 SkShaderBase::Context* shaderContext)
827 : INHERITED(device)
828 , fShader(paint.getShader())
829 , fShaderContext(shaderContext) {
830 SkASSERT(fShader);
831 SkASSERT(fShaderContext);
832
833 fShader->ref();
834 fShaderFlags = fShaderContext->getFlags();
835 fConstInY = SkToBool(fShaderFlags & SkShaderBase::kConstInY32_Flag);
836 }
837
~SkShaderBlitter()838 SkShaderBlitter::~SkShaderBlitter() {
839 fShader->unref();
840 }
841
842 ///////////////////////////////////////////////////////////////////////////////////////////////////
843
844 #ifdef SK_DEBUG
845
blitH(int x,int y,int width)846 void SkRectClipCheckBlitter::blitH(int x, int y, int width) {
847 SkASSERT(fClipRect.contains(SkIRect::MakeXYWH(x, y, width, 1)));
848 fBlitter->blitH(x, y, width);
849 }
850
blitAntiH(int x,int y,const SkAlpha aa[],const int16_t runs[])851 void SkRectClipCheckBlitter::blitAntiH(int x, int y, const SkAlpha aa[], const int16_t runs[]) {
852 const int16_t* iter = runs;
853 for (; *iter; iter += *iter)
854 ;
855 int width = iter - runs;
856 SkASSERT(fClipRect.contains(SkIRect::MakeXYWH(x, y, width, 1)));
857 fBlitter->blitAntiH(x, y, aa, runs);
858 }
859
blitV(int x,int y,int height,SkAlpha alpha)860 void SkRectClipCheckBlitter::blitV(int x, int y, int height, SkAlpha alpha) {
861 SkASSERT(fClipRect.contains(SkIRect::MakeXYWH(x, y, 1, height)));
862 fBlitter->blitV(x, y, height, alpha);
863 }
864
blitRect(int x,int y,int width,int height)865 void SkRectClipCheckBlitter::blitRect(int x, int y, int width, int height) {
866 SkASSERT(fClipRect.contains(SkIRect::MakeXYWH(x, y, width, height)));
867 fBlitter->blitRect(x, y, width, height);
868 }
869
blitAntiRect(int x,int y,int width,int height,SkAlpha leftAlpha,SkAlpha rightAlpha)870 void SkRectClipCheckBlitter::blitAntiRect(int x, int y, int width, int height,
871 SkAlpha leftAlpha, SkAlpha rightAlpha) {
872 bool skipLeft = !leftAlpha;
873 bool skipRight = !rightAlpha;
874 SkIRect r = SkIRect::MakeXYWH(x + skipLeft, y, width + 2 - skipRight - skipLeft, height);
875 SkASSERT(r.isEmpty() || fClipRect.contains(r));
876 fBlitter->blitAntiRect(x, y, width, height, leftAlpha, rightAlpha);
877 }
878
blitMask(const SkMask & mask,const SkIRect & clip)879 void SkRectClipCheckBlitter::blitMask(const SkMask& mask, const SkIRect& clip) {
880 SkASSERT(mask.fBounds.contains(clip));
881 SkASSERT(fClipRect.contains(clip));
882 fBlitter->blitMask(mask, clip);
883 }
884
justAnOpaqueColor(uint32_t * value)885 const SkPixmap* SkRectClipCheckBlitter::justAnOpaqueColor(uint32_t* value) {
886 return fBlitter->justAnOpaqueColor(value);
887 }
888
blitAntiH2(int x,int y,U8CPU a0,U8CPU a1)889 void SkRectClipCheckBlitter::blitAntiH2(int x, int y, U8CPU a0, U8CPU a1) {
890 SkASSERT(fClipRect.contains(SkIRect::MakeXYWH(x, y, 2, 1)));
891 fBlitter->blitAntiH2(x, y, a0, a1);
892 }
893
blitAntiV2(int x,int y,U8CPU a0,U8CPU a1)894 void SkRectClipCheckBlitter::blitAntiV2(int x, int y, U8CPU a0, U8CPU a1) {
895 SkASSERT(fClipRect.contains(SkIRect::MakeXYWH(x, y, 1, 2)));
896 fBlitter->blitAntiV2(x, y, a0, a1);
897 }
898
899 #endif
900