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 "GrReducedClip.h"
9
10 #include "GrAppliedClip.h"
11 #include "GrClip.h"
12 #include "GrColor.h"
13 #include "GrContextPriv.h"
14 #include "GrRenderTargetContext.h"
15 #include "GrRenderTargetContextPriv.h"
16 #include "GrDrawingManager.h"
17 #include "GrFixedClip.h"
18 #include "GrPathRenderer.h"
19 #include "GrStencilSettings.h"
20 #include "GrStencilClip.h"
21 #include "GrStyle.h"
22 #include "GrUserStencilSettings.h"
23 #include "SkClipOpPriv.h"
24 #include "ccpr/GrCoverageCountingPathRenderer.h"
25 #include "effects/GrAARectEffect.h"
26 #include "effects/GrConvexPolyEffect.h"
27 #include "effects/GrRRectEffect.h"
28
29 /**
30 * There are plenty of optimizations that could be added here. Maybe flips could be folded into
31 * earlier operations. Or would inserting flips and reversing earlier ops ever be a win? Perhaps
32 * for the case where the bounds are kInsideOut_BoundsType. We could restrict earlier operations
33 * based on later intersect operations, and perhaps remove intersect-rects. We could optionally
34 * take a rect in case the caller knows a bound on what is to be drawn through this clip.
35 */
GrReducedClip(const SkClipStack & stack,const SkRect & queryBounds,const GrShaderCaps * caps,int maxWindowRectangles,int maxAnalyticFPs,GrCoverageCountingPathRenderer * ccpr)36 GrReducedClip::GrReducedClip(const SkClipStack& stack, const SkRect& queryBounds,
37 const GrShaderCaps* caps, int maxWindowRectangles, int maxAnalyticFPs,
38 GrCoverageCountingPathRenderer* ccpr)
39 : fCaps(caps)
40 , fMaxWindowRectangles(maxWindowRectangles)
41 , fMaxAnalyticFPs(maxAnalyticFPs)
42 , fCCPR(fMaxAnalyticFPs ? ccpr : nullptr) {
43 SkASSERT(!queryBounds.isEmpty());
44 SkASSERT(fMaxWindowRectangles <= GrWindowRectangles::kMaxWindows);
45 fHasScissor = false;
46 fAAClipRectGenID = SK_InvalidGenID;
47
48 if (stack.isWideOpen()) {
49 fInitialState = InitialState::kAllIn;
50 return;
51 }
52
53 SkClipStack::BoundsType stackBoundsType;
54 SkRect stackBounds;
55 bool iior;
56 stack.getBounds(&stackBounds, &stackBoundsType, &iior);
57
58 if (GrClip::IsOutsideClip(stackBounds, queryBounds)) {
59 bool insideOut = SkClipStack::kInsideOut_BoundsType == stackBoundsType;
60 fInitialState = insideOut ? InitialState::kAllIn : InitialState::kAllOut;
61 return;
62 }
63
64 if (iior) {
65 // "Is intersection of rects" means the clip is a single rect indicated by the stack bounds.
66 // This should only be true if aa/non-aa status matches among all elements.
67 SkASSERT(SkClipStack::kNormal_BoundsType == stackBoundsType);
68 SkClipStack::Iter iter(stack, SkClipStack::Iter::kTop_IterStart);
69 if (!iter.prev()->isAA() || GrClip::IsPixelAligned(stackBounds)) {
70 // The clip is a non-aa rect. Here we just implement the entire thing using fScissor.
71 stackBounds.round(&fScissor);
72 fHasScissor = true;
73 fInitialState = fScissor.isEmpty() ? InitialState::kAllOut : InitialState::kAllIn;
74 return;
75 }
76 if (GrClip::IsInsideClip(stackBounds, queryBounds)) {
77 fInitialState = InitialState::kAllIn;
78 return;
79 }
80
81 SkRect tightBounds;
82 SkAssertResult(tightBounds.intersect(stackBounds, queryBounds));
83 fScissor = GrClip::GetPixelIBounds(tightBounds);
84 if (fScissor.isEmpty()) {
85 fInitialState = InitialState::kAllOut;
86 return;
87 }
88 fHasScissor = true;
89
90 fAAClipRect = stackBounds;
91 fAAClipRectGenID = stack.getTopmostGenID();
92 SkASSERT(SK_InvalidGenID != fAAClipRectGenID);
93
94 fInitialState = InitialState::kAllIn;
95 } else {
96 SkRect tighterQuery = queryBounds;
97 if (SkClipStack::kNormal_BoundsType == stackBoundsType) {
98 // Tighten the query by introducing a new clip at the stack's pixel boundaries. (This
99 // new clip will be enforced by the scissor.)
100 SkAssertResult(tighterQuery.intersect(GrClip::GetPixelBounds(stackBounds)));
101 }
102
103 fScissor = GrClip::GetPixelIBounds(tighterQuery);
104 if (fScissor.isEmpty()) {
105 fInitialState = InitialState::kAllOut;
106 return;
107 }
108 fHasScissor = true;
109
110 // Now that we have determined the bounds to use and filtered out the trivial cases, call
111 // the helper that actually walks the stack.
112 this->walkStack(stack, tighterQuery);
113 }
114
115 if (SK_InvalidGenID != fAAClipRectGenID && // Is there an AA clip rect?
116 ClipResult::kNotClipped == this->addAnalyticFP(fAAClipRect, Invert::kNo, GrAA::kYes)) {
117 if (fMaskElements.isEmpty()) {
118 // Use a replace since it is faster than intersect.
119 fMaskElements.addToHead(fAAClipRect, SkMatrix::I(), kReplace_SkClipOp, true /*doAA*/);
120 fInitialState = InitialState::kAllOut;
121 } else {
122 fMaskElements.addToTail(fAAClipRect, SkMatrix::I(), kIntersect_SkClipOp, true /*doAA*/);
123 }
124 fMaskRequiresAA = true;
125 fMaskGenID = fAAClipRectGenID;
126 }
127 }
128
walkStack(const SkClipStack & stack,const SkRect & queryBounds)129 void GrReducedClip::walkStack(const SkClipStack& stack, const SkRect& queryBounds) {
130 // walk backwards until we get to:
131 // a) the beginning
132 // b) an operation that is known to make the bounds all inside/outside
133 // c) a replace operation
134
135 enum class InitialTriState {
136 kUnknown = -1,
137 kAllIn = (int)GrReducedClip::InitialState::kAllIn,
138 kAllOut = (int)GrReducedClip::InitialState::kAllOut
139 } initialTriState = InitialTriState::kUnknown;
140
141 // During our backwards walk, track whether we've seen ops that either grow or shrink the clip.
142 // TODO: track these per saved clip so that we can consider them on the forward pass.
143 bool embiggens = false;
144 bool emsmallens = false;
145
146 // We use a slightly relaxed set of query bounds for element containment tests. This is to
147 // account for floating point rounding error that may have occurred during coord transforms.
148 SkRect relaxedQueryBounds = queryBounds.makeInset(GrClip::kBoundsTolerance,
149 GrClip::kBoundsTolerance);
150 if (relaxedQueryBounds.isEmpty()) {
151 relaxedQueryBounds = queryBounds;
152 }
153
154 SkClipStack::Iter iter(stack, SkClipStack::Iter::kTop_IterStart);
155 int numAAElements = 0;
156 while (InitialTriState::kUnknown == initialTriState) {
157 const Element* element = iter.prev();
158 if (nullptr == element) {
159 initialTriState = InitialTriState::kAllIn;
160 break;
161 }
162 if (SkClipStack::kEmptyGenID == element->getGenID()) {
163 initialTriState = InitialTriState::kAllOut;
164 break;
165 }
166 if (SkClipStack::kWideOpenGenID == element->getGenID()) {
167 initialTriState = InitialTriState::kAllIn;
168 break;
169 }
170
171 bool skippable = false;
172 bool isFlip = false; // does this op just flip the in/out state of every point in the bounds
173
174 switch (element->getOp()) {
175 case kDifference_SkClipOp:
176 // check if the shape subtracted either contains the entire bounds (and makes
177 // the clip empty) or is outside the bounds and therefore can be skipped.
178 if (element->isInverseFilled()) {
179 if (element->contains(relaxedQueryBounds)) {
180 skippable = true;
181 } else if (GrClip::IsOutsideClip(element->getBounds(), queryBounds)) {
182 initialTriState = InitialTriState::kAllOut;
183 skippable = true;
184 } else if (!embiggens) {
185 ClipResult result = this->clipInsideElement(element);
186 if (ClipResult::kMadeEmpty == result) {
187 return;
188 }
189 skippable = (ClipResult::kClipped == result);
190 }
191 } else {
192 if (element->contains(relaxedQueryBounds)) {
193 initialTriState = InitialTriState::kAllOut;
194 skippable = true;
195 } else if (GrClip::IsOutsideClip(element->getBounds(), queryBounds)) {
196 skippable = true;
197 } else if (!embiggens) {
198 ClipResult result = this->clipOutsideElement(element);
199 if (ClipResult::kMadeEmpty == result) {
200 return;
201 }
202 skippable = (ClipResult::kClipped == result);
203 }
204 }
205 if (!skippable) {
206 emsmallens = true;
207 }
208 break;
209 case kIntersect_SkClipOp:
210 // check if the shape intersected contains the entire bounds and therefore can
211 // be skipped or it is outside the entire bounds and therefore makes the clip
212 // empty.
213 if (element->isInverseFilled()) {
214 if (element->contains(relaxedQueryBounds)) {
215 initialTriState = InitialTriState::kAllOut;
216 skippable = true;
217 } else if (GrClip::IsOutsideClip(element->getBounds(), queryBounds)) {
218 skippable = true;
219 } else if (!embiggens) {
220 ClipResult result = this->clipOutsideElement(element);
221 if (ClipResult::kMadeEmpty == result) {
222 return;
223 }
224 skippable = (ClipResult::kClipped == result);
225 }
226 } else {
227 if (element->contains(relaxedQueryBounds)) {
228 skippable = true;
229 } else if (GrClip::IsOutsideClip(element->getBounds(), queryBounds)) {
230 initialTriState = InitialTriState::kAllOut;
231 skippable = true;
232 } else if (!embiggens) {
233 ClipResult result = this->clipInsideElement(element);
234 if (ClipResult::kMadeEmpty == result) {
235 return;
236 }
237 skippable = (ClipResult::kClipped == result);
238 }
239 }
240 if (!skippable) {
241 emsmallens = true;
242 }
243 break;
244 case kUnion_SkClipOp:
245 // If the union-ed shape contains the entire bounds then after this element
246 // the bounds is entirely inside the clip. If the union-ed shape is outside the
247 // bounds then this op can be skipped.
248 if (element->isInverseFilled()) {
249 if (element->contains(relaxedQueryBounds)) {
250 skippable = true;
251 } else if (GrClip::IsOutsideClip(element->getBounds(), queryBounds)) {
252 initialTriState = InitialTriState::kAllIn;
253 skippable = true;
254 }
255 } else {
256 if (element->contains(relaxedQueryBounds)) {
257 initialTriState = InitialTriState::kAllIn;
258 skippable = true;
259 } else if (GrClip::IsOutsideClip(element->getBounds(), queryBounds)) {
260 skippable = true;
261 }
262 }
263 if (!skippable) {
264 embiggens = true;
265 }
266 break;
267 case kXOR_SkClipOp:
268 // If the bounds is entirely inside the shape being xor-ed then the effect is
269 // to flip the inside/outside state of every point in the bounds. We may be
270 // able to take advantage of this in the forward pass. If the xor-ed shape
271 // doesn't intersect the bounds then it can be skipped.
272 if (element->isInverseFilled()) {
273 if (element->contains(relaxedQueryBounds)) {
274 skippable = true;
275 } else if (GrClip::IsOutsideClip(element->getBounds(), queryBounds)) {
276 isFlip = true;
277 }
278 } else {
279 if (element->contains(relaxedQueryBounds)) {
280 isFlip = true;
281 } else if (GrClip::IsOutsideClip(element->getBounds(), queryBounds)) {
282 skippable = true;
283 }
284 }
285 if (!skippable) {
286 emsmallens = embiggens = true;
287 }
288 break;
289 case kReverseDifference_SkClipOp:
290 // When the bounds is entirely within the rev-diff shape then this behaves like xor
291 // and reverses every point inside the bounds. If the shape is completely outside
292 // the bounds then we know after this element is applied that the bounds will be
293 // all outside the current clip.B
294 if (element->isInverseFilled()) {
295 if (element->contains(relaxedQueryBounds)) {
296 initialTriState = InitialTriState::kAllOut;
297 skippable = true;
298 } else if (GrClip::IsOutsideClip(element->getBounds(), queryBounds)) {
299 isFlip = true;
300 }
301 } else {
302 if (element->contains(relaxedQueryBounds)) {
303 isFlip = true;
304 } else if (GrClip::IsOutsideClip(element->getBounds(), queryBounds)) {
305 initialTriState = InitialTriState::kAllOut;
306 skippable = true;
307 }
308 }
309 if (!skippable) {
310 emsmallens = embiggens = true;
311 }
312 break;
313
314 case kReplace_SkClipOp:
315 // Replace will always terminate our walk. We will either begin the forward walk
316 // at the replace op or detect here than the shape is either completely inside
317 // or completely outside the bounds. In this latter case it can be skipped by
318 // setting the correct value for initialTriState.
319 if (element->isInverseFilled()) {
320 if (element->contains(relaxedQueryBounds)) {
321 initialTriState = InitialTriState::kAllOut;
322 skippable = true;
323 } else if (GrClip::IsOutsideClip(element->getBounds(), queryBounds)) {
324 initialTriState = InitialTriState::kAllIn;
325 skippable = true;
326 } else if (!embiggens) {
327 ClipResult result = this->clipOutsideElement(element);
328 if (ClipResult::kMadeEmpty == result) {
329 return;
330 }
331 if (ClipResult::kClipped == result) {
332 initialTriState = InitialTriState::kAllIn;
333 skippable = true;
334 }
335 }
336 } else {
337 if (element->contains(relaxedQueryBounds)) {
338 initialTriState = InitialTriState::kAllIn;
339 skippable = true;
340 } else if (GrClip::IsOutsideClip(element->getBounds(), queryBounds)) {
341 initialTriState = InitialTriState::kAllOut;
342 skippable = true;
343 } else if (!embiggens) {
344 ClipResult result = this->clipInsideElement(element);
345 if (ClipResult::kMadeEmpty == result) {
346 return;
347 }
348 if (ClipResult::kClipped == result) {
349 initialTriState = InitialTriState::kAllIn;
350 skippable = true;
351 }
352 }
353 }
354 if (!skippable) {
355 initialTriState = InitialTriState::kAllOut;
356 embiggens = emsmallens = true;
357 }
358 break;
359 default:
360 SkDEBUGFAIL("Unexpected op.");
361 break;
362 }
363 if (!skippable) {
364 if (fMaskElements.isEmpty()) {
365 // This will be the last element. Record the stricter genID.
366 fMaskGenID = element->getGenID();
367 }
368
369 // if it is a flip, change it to a bounds-filling rect
370 if (isFlip) {
371 SkASSERT(kXOR_SkClipOp == element->getOp() ||
372 kReverseDifference_SkClipOp == element->getOp());
373 fMaskElements.addToHead(SkRect::Make(fScissor), SkMatrix::I(),
374 kReverseDifference_SkClipOp, false);
375 } else {
376 Element* newElement = fMaskElements.addToHead(*element);
377 if (newElement->isAA()) {
378 ++numAAElements;
379 }
380 // Intersecting an inverse shape is the same as differencing the non-inverse shape.
381 // Replacing with an inverse shape is the same as setting initialState=kAllIn and
382 // differencing the non-inverse shape.
383 bool isReplace = kReplace_SkClipOp == newElement->getOp();
384 if (newElement->isInverseFilled() &&
385 (kIntersect_SkClipOp == newElement->getOp() || isReplace)) {
386 newElement->invertShapeFillType();
387 newElement->setOp(kDifference_SkClipOp);
388 if (isReplace) {
389 SkASSERT(InitialTriState::kAllOut == initialTriState);
390 initialTriState = InitialTriState::kAllIn;
391 }
392 }
393 }
394 }
395 }
396
397 if ((InitialTriState::kAllOut == initialTriState && !embiggens) ||
398 (InitialTriState::kAllIn == initialTriState && !emsmallens)) {
399 fMaskElements.reset();
400 numAAElements = 0;
401 } else {
402 Element* element = fMaskElements.headIter().get();
403 while (element) {
404 bool skippable = false;
405 switch (element->getOp()) {
406 case kDifference_SkClipOp:
407 // subtracting from the empty set yields the empty set.
408 skippable = InitialTriState::kAllOut == initialTriState;
409 break;
410 case kIntersect_SkClipOp:
411 // intersecting with the empty set yields the empty set
412 if (InitialTriState::kAllOut == initialTriState) {
413 skippable = true;
414 } else {
415 // We can clear to zero and then simply draw the clip element.
416 initialTriState = InitialTriState::kAllOut;
417 element->setOp(kReplace_SkClipOp);
418 }
419 break;
420 case kUnion_SkClipOp:
421 if (InitialTriState::kAllIn == initialTriState) {
422 // unioning the infinite plane with anything is a no-op.
423 skippable = true;
424 } else {
425 // unioning the empty set with a shape is the shape.
426 element->setOp(kReplace_SkClipOp);
427 }
428 break;
429 case kXOR_SkClipOp:
430 if (InitialTriState::kAllOut == initialTriState) {
431 // xor could be changed to diff in the kAllIn case, not sure it's a win.
432 element->setOp(kReplace_SkClipOp);
433 }
434 break;
435 case kReverseDifference_SkClipOp:
436 if (InitialTriState::kAllIn == initialTriState) {
437 // subtracting the whole plane will yield the empty set.
438 skippable = true;
439 initialTriState = InitialTriState::kAllOut;
440 } else {
441 // this picks up flips inserted in the backwards pass.
442 skippable = element->isInverseFilled() ?
443 GrClip::IsOutsideClip(element->getBounds(), queryBounds) :
444 element->contains(relaxedQueryBounds);
445 if (skippable) {
446 initialTriState = InitialTriState::kAllIn;
447 } else {
448 element->setOp(kReplace_SkClipOp);
449 }
450 }
451 break;
452 case kReplace_SkClipOp:
453 skippable = false; // we would have skipped it in the backwards walk if we
454 // could've.
455 break;
456 default:
457 SkDEBUGFAIL("Unexpected op.");
458 break;
459 }
460 if (!skippable) {
461 break;
462 } else {
463 if (element->isAA()) {
464 --numAAElements;
465 }
466 fMaskElements.popHead();
467 element = fMaskElements.headIter().get();
468 }
469 }
470 }
471 fMaskRequiresAA = numAAElements > 0;
472
473 SkASSERT(InitialTriState::kUnknown != initialTriState);
474 fInitialState = static_cast<GrReducedClip::InitialState>(initialTriState);
475 }
476
clipInsideElement(const Element * element)477 GrReducedClip::ClipResult GrReducedClip::clipInsideElement(const Element* element) {
478 SkIRect elementIBounds;
479 if (!element->isAA()) {
480 element->getBounds().round(&elementIBounds);
481 } else {
482 elementIBounds = GrClip::GetPixelIBounds(element->getBounds());
483 }
484 SkASSERT(fHasScissor);
485 if (!fScissor.intersect(elementIBounds)) {
486 this->makeEmpty();
487 return ClipResult::kMadeEmpty;
488 }
489
490 switch (element->getDeviceSpaceType()) {
491 case Element::DeviceSpaceType::kEmpty:
492 return ClipResult::kMadeEmpty;
493
494 case Element::DeviceSpaceType::kRect:
495 SkASSERT(element->getBounds() == element->getDeviceSpaceRect());
496 SkASSERT(!element->isInverseFilled());
497 if (element->isAA()) {
498 if (SK_InvalidGenID == fAAClipRectGenID) { // No AA clip rect yet?
499 fAAClipRect = element->getDeviceSpaceRect();
500 // fAAClipRectGenID is the value we should use for fMaskGenID if we end up
501 // moving the AA clip rect into the mask. The mask GenID is simply the topmost
502 // element's GenID. And since we walk the stack backwards, this means it's just
503 // the first element we don't skip during our walk.
504 fAAClipRectGenID = fMaskElements.isEmpty() ? element->getGenID() : fMaskGenID;
505 SkASSERT(SK_InvalidGenID != fAAClipRectGenID);
506 } else if (!fAAClipRect.intersect(element->getDeviceSpaceRect())) {
507 this->makeEmpty();
508 return ClipResult::kMadeEmpty;
509 }
510 }
511 return ClipResult::kClipped;
512
513 case Element::DeviceSpaceType::kRRect:
514 SkASSERT(!element->isInverseFilled());
515 return this->addAnalyticFP(element->getDeviceSpaceRRect(), Invert::kNo,
516 GrAA(element->isAA()));
517
518 case Element::DeviceSpaceType::kPath:
519 return this->addAnalyticFP(element->getDeviceSpacePath(),
520 Invert(element->isInverseFilled()), GrAA(element->isAA()));
521 }
522
523 SK_ABORT("Unexpected DeviceSpaceType");
524 return ClipResult::kNotClipped;
525 }
526
clipOutsideElement(const Element * element)527 GrReducedClip::ClipResult GrReducedClip::clipOutsideElement(const Element* element) {
528 switch (element->getDeviceSpaceType()) {
529 case Element::DeviceSpaceType::kEmpty:
530 return ClipResult::kMadeEmpty;
531
532 case Element::DeviceSpaceType::kRect:
533 SkASSERT(!element->isInverseFilled());
534 if (fWindowRects.count() < fMaxWindowRectangles) {
535 // Clip out the inside of every rect. We won't be able to entirely skip the AA ones,
536 // but it saves processing time.
537 this->addWindowRectangle(element->getDeviceSpaceRect(), element->isAA());
538 if (!element->isAA()) {
539 return ClipResult::kClipped;
540 }
541 }
542 return this->addAnalyticFP(element->getDeviceSpaceRect(), Invert::kYes,
543 GrAA(element->isAA()));
544
545 case Element::DeviceSpaceType::kRRect: {
546 SkASSERT(!element->isInverseFilled());
547 const SkRRect& clipRRect = element->getDeviceSpaceRRect();
548 ClipResult clipResult = this->addAnalyticFP(clipRRect, Invert::kYes,
549 GrAA(element->isAA()));
550 if (fWindowRects.count() >= fMaxWindowRectangles) {
551 return clipResult;
552 }
553
554 // Clip out the interiors of round rects with two window rectangles in the shape of a
555 // "plus". This doesn't let us skip the clip element, but still saves processing time.
556 SkVector insetTL = clipRRect.radii(SkRRect::kUpperLeft_Corner);
557 SkVector insetBR = clipRRect.radii(SkRRect::kLowerRight_Corner);
558 if (SkRRect::kComplex_Type == clipRRect.getType()) {
559 const SkVector& insetTR = clipRRect.radii(SkRRect::kUpperRight_Corner);
560 const SkVector& insetBL = clipRRect.radii(SkRRect::kLowerLeft_Corner);
561 insetTL.fX = SkTMax(insetTL.x(), insetBL.x());
562 insetTL.fY = SkTMax(insetTL.y(), insetTR.y());
563 insetBR.fX = SkTMax(insetBR.x(), insetTR.x());
564 insetBR.fY = SkTMax(insetBR.y(), insetBL.y());
565 }
566 const SkRect& bounds = clipRRect.getBounds();
567 if (insetTL.x() + insetBR.x() >= bounds.width() ||
568 insetTL.y() + insetBR.y() >= bounds.height()) {
569 return clipResult; // The interior "plus" is empty.
570 }
571
572 SkRect horzRect = SkRect::MakeLTRB(bounds.left(), bounds.top() + insetTL.y(),
573 bounds.right(), bounds.bottom() - insetBR.y());
574 this->addWindowRectangle(horzRect, element->isAA());
575
576 if (fWindowRects.count() < fMaxWindowRectangles) {
577 SkRect vertRect = SkRect::MakeLTRB(bounds.left() + insetTL.x(), bounds.top(),
578 bounds.right() - insetBR.x(), bounds.bottom());
579 this->addWindowRectangle(vertRect, element->isAA());
580 }
581
582 return clipResult;
583 }
584
585 case Element::DeviceSpaceType::kPath:
586 return this->addAnalyticFP(element->getDeviceSpacePath(),
587 Invert(!element->isInverseFilled()), GrAA(element->isAA()));
588 }
589
590 SK_ABORT("Unexpected DeviceSpaceType");
591 return ClipResult::kNotClipped;
592 }
593
addWindowRectangle(const SkRect & elementInteriorRect,bool elementIsAA)594 inline void GrReducedClip::addWindowRectangle(const SkRect& elementInteriorRect, bool elementIsAA) {
595 SkIRect window;
596 if (!elementIsAA) {
597 elementInteriorRect.round(&window);
598 } else {
599 elementInteriorRect.roundIn(&window);
600 }
601 if (!window.isEmpty()) { // Skip very thin windows that round to zero or negative dimensions.
602 fWindowRects.addWindow(window);
603 }
604 }
605
GetClipEdgeType(Invert invert,GrAA aa)606 GrClipEdgeType GrReducedClip::GetClipEdgeType(Invert invert, GrAA aa) {
607 if (Invert::kNo == invert) {
608 return (GrAA::kYes == aa) ? GrClipEdgeType::kFillAA : GrClipEdgeType::kFillBW;
609 } else {
610 return (GrAA::kYes == aa) ? GrClipEdgeType::kInverseFillAA : GrClipEdgeType::kInverseFillBW;
611 }
612 }
613
addAnalyticFP(const SkRect & deviceSpaceRect,Invert invert,GrAA aa)614 GrReducedClip::ClipResult GrReducedClip::addAnalyticFP(const SkRect& deviceSpaceRect,
615 Invert invert, GrAA aa) {
616 if (this->numAnalyticFPs() >= fMaxAnalyticFPs) {
617 return ClipResult::kNotClipped;
618 }
619
620 fAnalyticFPs.push_back(GrAARectEffect::Make(GetClipEdgeType(invert, aa), deviceSpaceRect));
621 SkASSERT(fAnalyticFPs.back());
622
623 return ClipResult::kClipped;
624 }
625
addAnalyticFP(const SkRRect & deviceSpaceRRect,Invert invert,GrAA aa)626 GrReducedClip::ClipResult GrReducedClip::addAnalyticFP(const SkRRect& deviceSpaceRRect,
627 Invert invert, GrAA aa) {
628 if (this->numAnalyticFPs() >= fMaxAnalyticFPs) {
629 return ClipResult::kNotClipped;
630 }
631
632 if (auto fp = GrRRectEffect::Make(GetClipEdgeType(invert, aa), deviceSpaceRRect, *fCaps)) {
633 fAnalyticFPs.push_back(std::move(fp));
634 return ClipResult::kClipped;
635 }
636
637 SkPath deviceSpacePath;
638 deviceSpacePath.setIsVolatile(true);
639 deviceSpacePath.addRRect(deviceSpaceRRect);
640 return this->addAnalyticFP(deviceSpacePath, invert, aa);
641 }
642
addAnalyticFP(const SkPath & deviceSpacePath,Invert invert,GrAA aa)643 GrReducedClip::ClipResult GrReducedClip::addAnalyticFP(const SkPath& deviceSpacePath,
644 Invert invert, GrAA aa) {
645 if (this->numAnalyticFPs() >= fMaxAnalyticFPs) {
646 return ClipResult::kNotClipped;
647 }
648
649 if (auto fp = GrConvexPolyEffect::Make(GetClipEdgeType(invert, aa), deviceSpacePath)) {
650 fAnalyticFPs.push_back(std::move(fp));
651 return ClipResult::kClipped;
652 }
653
654 if (fCCPR && GrAA::kYes == aa && fCCPR->canMakeClipProcessor(deviceSpacePath)) {
655 // Set aside CCPR paths for later. We will create their clip FPs once we know the ID of the
656 // opList they will operate in.
657 SkPath& ccprClipPath = fCCPRClipPaths.push_back(deviceSpacePath);
658 if (Invert::kYes == invert) {
659 ccprClipPath.toggleInverseFillType();
660 }
661 return ClipResult::kClipped;
662 }
663
664 return ClipResult::kNotClipped;
665 }
666
makeEmpty()667 void GrReducedClip::makeEmpty() {
668 fHasScissor = false;
669 fAAClipRectGenID = SK_InvalidGenID;
670 fWindowRects.reset();
671 fMaskElements.reset();
672 fInitialState = InitialState::kAllOut;
673 }
674
675 ////////////////////////////////////////////////////////////////////////////////
676 // Create a 8-bit clip mask in alpha
677
stencil_element(GrRenderTargetContext * rtc,const GrFixedClip & clip,const GrUserStencilSettings * ss,const SkMatrix & viewMatrix,const SkClipStack::Element * element)678 static bool stencil_element(GrRenderTargetContext* rtc,
679 const GrFixedClip& clip,
680 const GrUserStencilSettings* ss,
681 const SkMatrix& viewMatrix,
682 const SkClipStack::Element* element) {
683 GrAA aa = GrAA(element->isAA());
684 switch (element->getDeviceSpaceType()) {
685 case SkClipStack::Element::DeviceSpaceType::kEmpty:
686 SkDEBUGFAIL("Should never get here with an empty element.");
687 break;
688 case SkClipStack::Element::DeviceSpaceType::kRect:
689 return rtc->priv().drawAndStencilRect(clip, ss, (SkRegion::Op)element->getOp(),
690 element->isInverseFilled(), aa, viewMatrix,
691 element->getDeviceSpaceRect());
692 break;
693 default: {
694 SkPath path;
695 element->asDeviceSpacePath(&path);
696 if (path.isInverseFillType()) {
697 path.toggleInverseFillType();
698 }
699
700 return rtc->priv().drawAndStencilPath(clip, ss, (SkRegion::Op)element->getOp(),
701 element->isInverseFilled(), aa, viewMatrix, path);
702 break;
703 }
704 }
705
706 return false;
707 }
708
draw_element(GrRenderTargetContext * rtc,const GrClip & clip,GrPaint && paint,GrAA aa,const SkMatrix & viewMatrix,const SkClipStack::Element * element)709 static void draw_element(GrRenderTargetContext* rtc,
710 const GrClip& clip, // TODO: can this just always be WideOpen?
711 GrPaint&& paint,
712 GrAA aa,
713 const SkMatrix& viewMatrix,
714 const SkClipStack::Element* element) {
715 // TODO: Draw rrects directly here.
716 switch (element->getDeviceSpaceType()) {
717 case SkClipStack::Element::DeviceSpaceType::kEmpty:
718 SkDEBUGFAIL("Should never get here with an empty element.");
719 break;
720 case SkClipStack::Element::DeviceSpaceType::kRect:
721 rtc->drawRect(clip, std::move(paint), aa, viewMatrix, element->getDeviceSpaceRect());
722 break;
723 default: {
724 SkPath path;
725 element->asDeviceSpacePath(&path);
726 if (path.isInverseFillType()) {
727 path.toggleInverseFillType();
728 }
729
730 rtc->drawPath(clip, std::move(paint), aa, viewMatrix, path, GrStyle::SimpleFill());
731 break;
732 }
733 }
734 }
735
drawAlphaClipMask(GrRenderTargetContext * rtc) const736 bool GrReducedClip::drawAlphaClipMask(GrRenderTargetContext* rtc) const {
737 // The texture may be larger than necessary, this rect represents the part of the texture
738 // we populate with a rasterization of the clip.
739 GrFixedClip clip(SkIRect::MakeWH(fScissor.width(), fScissor.height()));
740
741 if (!fWindowRects.empty()) {
742 clip.setWindowRectangles(fWindowRects.makeOffset(-fScissor.left(), -fScissor.top()),
743 GrWindowRectsState::Mode::kExclusive);
744 }
745
746 // The scratch texture that we are drawing into can be substantially larger than the mask. Only
747 // clear the part that we care about.
748 GrColor initialCoverage = InitialState::kAllIn == this->initialState() ? -1 : 0;
749 rtc->priv().clear(clip, initialCoverage, GrRenderTargetContext::CanClearFullscreen::kYes);
750
751 // Set the matrix so that rendered clip elements are transformed to mask space from clip space.
752 SkMatrix translate;
753 translate.setTranslate(SkIntToScalar(-fScissor.left()), SkIntToScalar(-fScissor.top()));
754
755 // walk through each clip element and perform its set op
756 for (ElementList::Iter iter(fMaskElements); iter.get(); iter.next()) {
757 const Element* element = iter.get();
758 SkRegion::Op op = (SkRegion::Op)element->getOp();
759 GrAA aa = GrAA(element->isAA());
760 bool invert = element->isInverseFilled();
761 if (invert || SkRegion::kIntersect_Op == op || SkRegion::kReverseDifference_Op == op) {
762 // draw directly into the result with the stencil set to make the pixels affected
763 // by the clip shape be non-zero.
764 static constexpr GrUserStencilSettings kStencilInElement(
765 GrUserStencilSettings::StaticInit<
766 0xffff,
767 GrUserStencilTest::kAlways,
768 0xffff,
769 GrUserStencilOp::kReplace,
770 GrUserStencilOp::kReplace,
771 0xffff>()
772 );
773 if (!stencil_element(rtc, clip, &kStencilInElement, translate, element)) {
774 return false;
775 }
776
777 // Draw to the exterior pixels (those with a zero stencil value).
778 static constexpr GrUserStencilSettings kDrawOutsideElement(
779 GrUserStencilSettings::StaticInit<
780 0x0000,
781 GrUserStencilTest::kEqual,
782 0xffff,
783 GrUserStencilOp::kZero,
784 GrUserStencilOp::kZero,
785 0xffff>()
786 );
787 if (!rtc->priv().drawAndStencilRect(clip, &kDrawOutsideElement, op, !invert, GrAA::kNo,
788 translate, SkRect::Make(fScissor))) {
789 return false;
790 }
791 } else {
792 // all the remaining ops can just be directly draw into the accumulation buffer
793 GrPaint paint;
794 paint.setCoverageSetOpXPFactory(op, false);
795
796 draw_element(rtc, clip, std::move(paint), aa, translate, element);
797 }
798 }
799
800 return true;
801 }
802
803 ////////////////////////////////////////////////////////////////////////////////
804 // Create a 1-bit clip mask in the stencil buffer.
805
drawStencilClipMask(GrContext * context,GrRenderTargetContext * renderTargetContext) const806 bool GrReducedClip::drawStencilClipMask(GrContext* context,
807 GrRenderTargetContext* renderTargetContext) const {
808 // We set the current clip to the bounds so that our recursive draws are scissored to them.
809 GrStencilClip stencilClip(fScissor, this->maskGenID());
810
811 if (!fWindowRects.empty()) {
812 stencilClip.fixedClip().setWindowRectangles(fWindowRects,
813 GrWindowRectsState::Mode::kExclusive);
814 }
815
816 bool initialState = InitialState::kAllIn == this->initialState();
817 renderTargetContext->priv().clearStencilClip(stencilClip.fixedClip(), initialState);
818
819 // walk through each clip element and perform its set op with the existing clip.
820 for (ElementList::Iter iter(fMaskElements); iter.get(); iter.next()) {
821 const Element* element = iter.get();
822 GrAAType aaType = GrAAType::kNone;
823 if (element->isAA() && GrFSAAType::kNone != renderTargetContext->fsaaType()) {
824 aaType = GrAAType::kMSAA;
825 }
826
827 bool fillInverted = false;
828
829 // This will be used to determine whether the clip shape can be rendered into the
830 // stencil with arbitrary stencil settings.
831 GrPathRenderer::StencilSupport stencilSupport;
832
833 SkRegion::Op op = (SkRegion::Op)element->getOp();
834
835 GrPathRenderer* pr = nullptr;
836 SkPath clipPath;
837 if (Element::DeviceSpaceType::kRect == element->getDeviceSpaceType()) {
838 stencilSupport = GrPathRenderer::kNoRestriction_StencilSupport;
839 fillInverted = false;
840 } else {
841 element->asDeviceSpacePath(&clipPath);
842 fillInverted = clipPath.isInverseFillType();
843 if (fillInverted) {
844 clipPath.toggleInverseFillType();
845 }
846
847 GrShape shape(clipPath, GrStyle::SimpleFill());
848 GrPathRenderer::CanDrawPathArgs canDrawArgs;
849 canDrawArgs.fCaps = context->caps();
850 canDrawArgs.fClipConservativeBounds = &stencilClip.fixedClip().scissorRect();
851 canDrawArgs.fViewMatrix = &SkMatrix::I();
852 canDrawArgs.fShape = &shape;
853 canDrawArgs.fAAType = aaType;
854 canDrawArgs.fHasUserStencilSettings = false;
855
856 GrDrawingManager* dm = context->contextPriv().drawingManager();
857 pr = dm->getPathRenderer(canDrawArgs, false, GrPathRendererChain::DrawType::kStencil,
858 &stencilSupport);
859 if (!pr) {
860 return false;
861 }
862 }
863
864 bool canRenderDirectToStencil =
865 GrPathRenderer::kNoRestriction_StencilSupport == stencilSupport;
866 bool drawDirectToClip; // Given the renderer, the element,
867 // fill rule, and set operation should
868 // we render the element directly to
869 // stencil bit used for clipping.
870 GrUserStencilSettings const* const* stencilPasses =
871 GrStencilSettings::GetClipPasses(op, canRenderDirectToStencil, fillInverted,
872 &drawDirectToClip);
873
874 // draw the element to the client stencil bits if necessary
875 if (!drawDirectToClip) {
876 static constexpr GrUserStencilSettings kDrawToStencil(
877 GrUserStencilSettings::StaticInit<
878 0x0000,
879 GrUserStencilTest::kAlways,
880 0xffff,
881 GrUserStencilOp::kIncMaybeClamp,
882 GrUserStencilOp::kIncMaybeClamp,
883 0xffff>()
884 );
885 if (Element::DeviceSpaceType::kRect == element->getDeviceSpaceType()) {
886 renderTargetContext->priv().stencilRect(stencilClip.fixedClip(), &kDrawToStencil,
887 aaType, SkMatrix::I(),
888 element->getDeviceSpaceRect());
889 } else {
890 if (!clipPath.isEmpty()) {
891 GrShape shape(clipPath, GrStyle::SimpleFill());
892 if (canRenderDirectToStencil) {
893 GrPaint paint;
894 paint.setXPFactory(GrDisableColorXPFactory::Get());
895
896 GrPathRenderer::DrawPathArgs args{context,
897 std::move(paint),
898 &kDrawToStencil,
899 renderTargetContext,
900 &stencilClip.fixedClip(),
901 &stencilClip.fixedClip().scissorRect(),
902 &SkMatrix::I(),
903 &shape,
904 aaType,
905 false};
906 pr->drawPath(args);
907 } else {
908 GrPathRenderer::StencilPathArgs args;
909 args.fContext = context;
910 args.fRenderTargetContext = renderTargetContext;
911 args.fClip = &stencilClip.fixedClip();
912 args.fClipConservativeBounds = &stencilClip.fixedClip().scissorRect();
913 args.fViewMatrix = &SkMatrix::I();
914 args.fAAType = aaType;
915 args.fShape = &shape;
916 pr->stencilPath(args);
917 }
918 }
919 }
920 }
921
922 // now we modify the clip bit by rendering either the clip
923 // element directly or a bounding rect of the entire clip.
924 for (GrUserStencilSettings const* const* pass = stencilPasses; *pass; ++pass) {
925 if (drawDirectToClip) {
926 if (Element::DeviceSpaceType::kRect == element->getDeviceSpaceType()) {
927 renderTargetContext->priv().stencilRect(stencilClip, *pass, aaType,
928 SkMatrix::I(),
929 element->getDeviceSpaceRect());
930 } else {
931 GrShape shape(clipPath, GrStyle::SimpleFill());
932 GrPaint paint;
933 paint.setXPFactory(GrDisableColorXPFactory::Get());
934 GrPathRenderer::DrawPathArgs args{context,
935 std::move(paint),
936 *pass,
937 renderTargetContext,
938 &stencilClip,
939 &stencilClip.fixedClip().scissorRect(),
940 &SkMatrix::I(),
941 &shape,
942 aaType,
943 false};
944 pr->drawPath(args);
945 }
946 } else {
947 // The view matrix is setup to do clip space -> stencil space translation, so
948 // draw rect in clip space.
949 renderTargetContext->priv().stencilRect(stencilClip, *pass, aaType, SkMatrix::I(),
950 SkRect::Make(fScissor));
951 }
952 }
953 }
954 return true;
955 }
956
finishAndDetachAnalyticFPs(GrProxyProvider * proxyProvider,uint32_t opListID,int rtWidth,int rtHeight)957 std::unique_ptr<GrFragmentProcessor> GrReducedClip::finishAndDetachAnalyticFPs(
958 GrProxyProvider* proxyProvider, uint32_t opListID,
959 int rtWidth, int rtHeight) {
960 // Make sure finishAndDetachAnalyticFPs hasn't been called already.
961 SkDEBUGCODE(for (const auto& fp : fAnalyticFPs) { SkASSERT(fp); })
962
963 if (!fCCPRClipPaths.empty()) {
964 fAnalyticFPs.reserve(fAnalyticFPs.count() + fCCPRClipPaths.count());
965 for (const SkPath& ccprClipPath : fCCPRClipPaths) {
966 SkASSERT(fHasScissor);
967 auto fp = fCCPR->makeClipProcessor(proxyProvider, opListID, ccprClipPath, fScissor,
968 rtWidth, rtHeight);
969 fAnalyticFPs.push_back(std::move(fp));
970 }
971 fCCPRClipPaths.reset();
972 }
973
974 return GrFragmentProcessor::RunInSeries(fAnalyticFPs.begin(), fAnalyticFPs.count());
975 }
976