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1 /*
2  * Copyright 2013 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 "include/private/SkPathRef.h"
9 
10 #include "include/core/SkMatrix.h"
11 #include "include/core/SkPath.h"
12 #include "include/core/SkRRect.h"
13 #include "include/private/base/SkFloatingPoint.h"
14 #include "include/private/base/SkOnce.h"
15 #include "src/base/SkVx.h"
16 #include "src/core/SkPathPriv.h"
17 
18 #include <cstring>
19 #include <utility>
20 
21 #ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
22     static constexpr int kPathRefGenIDBitCnt = 30; // leave room for the fill type (skbug.com/1762)
23 #else
24     static constexpr int kPathRefGenIDBitCnt = 32;
25 #endif
26 
27 //////////////////////////////////////////////////////////////////////////////
Editor(sk_sp<SkPathRef> * pathRef,int incReserveVerbs,int incReservePoints,int incReserveConics)28 SkPathRef::Editor::Editor(sk_sp<SkPathRef>* pathRef,
29                           int incReserveVerbs,
30                           int incReservePoints,
31                           int incReserveConics)
32 {
33     SkASSERT(incReserveVerbs >= 0);
34     SkASSERT(incReservePoints >= 0);
35 
36     if ((*pathRef)->unique()) {
37         (*pathRef)->incReserve(incReserveVerbs, incReservePoints, incReserveConics);
38     } else {
39         SkPathRef* copy;
40         // No need to copy if the existing ref is the empty ref (because it doesn't contain
41         // anything).
42         if (!(*pathRef)->isInitialEmptyPathRef()) {
43             copy = new SkPathRef;
44             copy->copy(**pathRef, incReserveVerbs, incReservePoints, incReserveConics);
45         } else {
46             // Size previously empty paths to exactly fit the supplied hints. The assumpion is
47             // the caller knows the exact size they want (as happens in chrome when deserializing
48             // paths).
49             copy = new SkPathRef(incReserveVerbs, incReservePoints, incReserveConics);
50         }
51         pathRef->reset(copy);
52     }
53     fPathRef = pathRef->get();
54     fPathRef->callGenIDChangeListeners();
55     fPathRef->fGenerationID = 0;
56     fPathRef->fBoundsIsDirty = true;
57     SkDEBUGCODE(fPathRef->fEditorsAttached++;)
58 }
59 
60 //////////////////////////////////////////////////////////////////////////////
61 
approximateBytesUsed() const62 size_t SkPathRef::approximateBytesUsed() const {
63     return sizeof(SkPathRef)
64          + fPoints      .capacity() * sizeof(fPoints      [0])
65          + fVerbs       .capacity() * sizeof(fVerbs       [0])
66          + fConicWeights.capacity() * sizeof(fConicWeights[0]);
67 }
68 
~SkPathRef()69 SkPathRef::~SkPathRef() {
70     // Deliberately don't validate() this path ref, otherwise there's no way
71     // to read one that's not valid and then free its memory without asserting.
72     SkDEBUGCODE(fGenerationID = 0xEEEEEEEE;)
73     SkDEBUGCODE(fEditorsAttached.store(0x7777777);)
74 }
75 
sk_create_empty_pathref()76 SkPathRef* sk_create_empty_pathref() {
77     SkPathRef* empty = new SkPathRef;
78     empty->computeBounds();
79     return empty;
80 }
81 
82 static SkPathRef* gEmpty = sk_create_empty_pathref();
83 
CreateEmpty()84 SkPathRef* SkPathRef::CreateEmpty() {
85     return SkRef(gEmpty);
86 }
87 
transform_dir_and_start(const SkMatrix & matrix,bool isRRect,bool * isCCW,unsigned * start)88 static void transform_dir_and_start(const SkMatrix& matrix, bool isRRect, bool* isCCW,
89                                     unsigned* start) {
90     int inStart = *start;
91     int rm = 0;
92     if (isRRect) {
93         // Degenerate rrect indices to oval indices and remember the remainder.
94         // Ovals have one index per side whereas rrects have two.
95         rm = inStart & 0b1;
96         inStart /= 2;
97     }
98     // Is the antidiagonal non-zero (otherwise the diagonal is zero)
99     int antiDiag;
100     // Is the non-zero value in the top row (either kMScaleX or kMSkewX) negative
101     int topNeg;
102     // Are the two non-zero diagonal or antidiagonal values the same sign.
103     int sameSign;
104     if (matrix.get(SkMatrix::kMScaleX) != 0) {
105         antiDiag = 0b00;
106         if (matrix.get(SkMatrix::kMScaleX) > 0) {
107             topNeg = 0b00;
108             sameSign = matrix.get(SkMatrix::kMScaleY) > 0 ? 0b01 : 0b00;
109         } else {
110             topNeg = 0b10;
111             sameSign = matrix.get(SkMatrix::kMScaleY) > 0 ? 0b00 : 0b01;
112         }
113     } else {
114         antiDiag = 0b01;
115         if (matrix.get(SkMatrix::kMSkewX) > 0) {
116             topNeg = 0b00;
117             sameSign = matrix.get(SkMatrix::kMSkewY) > 0 ? 0b01 : 0b00;
118         } else {
119             topNeg = 0b10;
120             sameSign = matrix.get(SkMatrix::kMSkewY) > 0 ? 0b00 : 0b01;
121         }
122     }
123     if (sameSign != antiDiag) {
124         // This is a rotation (and maybe scale). The direction is unchanged.
125         // Trust me on the start computation (or draw yourself some pictures)
126         *start = (inStart + 4 - (topNeg | antiDiag)) % 4;
127         SkASSERT(*start < 4);
128         if (isRRect) {
129             *start = 2 * *start + rm;
130         }
131     } else {
132         // This is a mirror (and maybe scale). The direction is reversed.
133         *isCCW = !*isCCW;
134         // Trust me on the start computation (or draw yourself some pictures)
135         *start = (6 + (topNeg | antiDiag) - inStart) % 4;
136         SkASSERT(*start < 4);
137         if (isRRect) {
138             *start = 2 * *start + (rm ? 0 : 1);
139         }
140     }
141 }
142 
CreateTransformedCopy(sk_sp<SkPathRef> * dst,const SkPathRef & src,const SkMatrix & matrix)143 void SkPathRef::CreateTransformedCopy(sk_sp<SkPathRef>* dst,
144                                       const SkPathRef& src,
145                                       const SkMatrix& matrix) {
146     SkDEBUGCODE(src.validate();)
147     if (matrix.isIdentity()) {
148         if (dst->get() != &src) {
149             src.ref();
150             dst->reset(const_cast<SkPathRef*>(&src));
151             SkDEBUGCODE((*dst)->validate();)
152         }
153         return;
154     }
155 
156     sk_sp<const SkPathRef> srcKeepAlive;
157     if (!(*dst)->unique()) {
158         // If dst and src are the same then we are about to drop our only ref on the common path
159         // ref. Some other thread may have owned src when we checked unique() above but it may not
160         // continue to do so. Add another ref so we continue to be an owner until we're done.
161         if (dst->get() == &src) {
162             srcKeepAlive.reset(SkRef(&src));
163         }
164         dst->reset(new SkPathRef);
165     }
166 
167     if (dst->get() != &src) {
168         (*dst)->fVerbs = src.fVerbs;
169         (*dst)->fConicWeights = src.fConicWeights;
170         (*dst)->callGenIDChangeListeners();
171         (*dst)->fGenerationID = 0;  // mark as dirty
172         // don't copy, just allocate the points
173         (*dst)->fPoints.resize(src.fPoints.size());
174     }
175     matrix.mapPoints((*dst)->fPoints.begin(), src.fPoints.begin(), src.fPoints.size());
176 
177     // Need to check this here in case (&src == dst)
178     bool canXformBounds = !src.fBoundsIsDirty && matrix.rectStaysRect() && src.countPoints() > 1;
179 
180     /*
181      *  Here we optimize the bounds computation, by noting if the bounds are
182      *  already known, and if so, we just transform those as well and mark
183      *  them as "known", rather than force the transformed path to have to
184      *  recompute them.
185      *
186      *  Special gotchas if the path is effectively empty (<= 1 point) or
187      *  if it is non-finite. In those cases bounds need to stay empty,
188      *  regardless of the matrix.
189      */
190     if (canXformBounds) {
191         (*dst)->fBoundsIsDirty = false;
192         if (src.fIsFinite) {
193             matrix.mapRect(&(*dst)->fBounds, src.fBounds);
194             if (!((*dst)->fIsFinite = (*dst)->fBounds.isFinite())) {
195                 (*dst)->fBounds.setEmpty();
196             }
197         } else {
198             (*dst)->fIsFinite = false;
199             (*dst)->fBounds.setEmpty();
200         }
201     } else {
202         (*dst)->fBoundsIsDirty = true;
203     }
204 
205     (*dst)->fSegmentMask = src.fSegmentMask;
206 
207     // It's an oval only if it stays a rect. Technically if scale is uniform, then it would stay an
208     // arc. For now, don't bother handling that (we'd also need to fixup the angles for negative
209     // scale, etc.)
210     bool rectStaysRect = matrix.rectStaysRect();
211     const PathType newType =
212             (rectStaysRect && src.fType != PathType::kArc) ? src.fType : PathType::kGeneral;
213     (*dst)->fType = newType;
214     if (newType == PathType::kOval || newType == PathType::kRRect) {
215         unsigned start = src.fRRectOrOvalStartIdx;
216         bool isCCW = SkToBool(src.fRRectOrOvalIsCCW);
217         transform_dir_and_start(matrix, newType == PathType::kRRect, &isCCW, &start);
218         (*dst)->fRRectOrOvalIsCCW = isCCW;
219         (*dst)->fRRectOrOvalStartIdx = start;
220     }
221 
222     if (dst->get() == &src) {
223         (*dst)->callGenIDChangeListeners();
224         (*dst)->fGenerationID = 0;
225     }
226 
227     SkDEBUGCODE((*dst)->validate();)
228 }
229 
Rewind(sk_sp<SkPathRef> * pathRef)230 void SkPathRef::Rewind(sk_sp<SkPathRef>* pathRef) {
231     if ((*pathRef)->unique()) {
232         SkDEBUGCODE((*pathRef)->validate();)
233         (*pathRef)->callGenIDChangeListeners();
234         (*pathRef)->fBoundsIsDirty = true;  // this also invalidates fIsFinite
235         (*pathRef)->fGenerationID = 0;
236         (*pathRef)->fPoints.clear();
237         (*pathRef)->fVerbs.clear();
238         (*pathRef)->fConicWeights.clear();
239         (*pathRef)->fSegmentMask = 0;
240         (*pathRef)->fType = PathType::kGeneral;
241         SkDEBUGCODE((*pathRef)->validate();)
242     } else {
243         int oldVCnt = (*pathRef)->countVerbs();
244         int oldPCnt = (*pathRef)->countPoints();
245         pathRef->reset(new SkPathRef);
246         (*pathRef)->resetToSize(0, 0, 0, oldVCnt, oldPCnt);
247     }
248 }
249 
operator ==(const SkPathRef & ref) const250 bool SkPathRef::operator== (const SkPathRef& ref) const {
251     SkDEBUGCODE(this->validate();)
252     SkDEBUGCODE(ref.validate();)
253 
254     // We explicitly check fSegmentMask as a quick-reject. We could skip it,
255     // since it is only a cache of info in the fVerbs, but its a fast way to
256     // notice a difference
257     if (fSegmentMask != ref.fSegmentMask) {
258         return false;
259     }
260 
261     bool genIDMatch = fGenerationID && fGenerationID == ref.fGenerationID;
262 #ifdef SK_RELEASE
263     if (genIDMatch) {
264         return true;
265     }
266 #endif
267     if (fPoints != ref.fPoints || fConicWeights != ref.fConicWeights || fVerbs != ref.fVerbs) {
268         SkASSERT(!genIDMatch);
269         return false;
270     }
271     if (ref.fVerbs.empty()) {
272         SkASSERT(ref.fPoints.empty());
273     }
274     return true;
275 }
276 
copy(const SkPathRef & ref,int additionalReserveVerbs,int additionalReservePoints,int additionalReserveConics)277 void SkPathRef::copy(const SkPathRef& ref,
278                      int additionalReserveVerbs,
279                      int additionalReservePoints,
280                      int additionalReserveConics) {
281     SkDEBUGCODE(this->validate();)
282     this->resetToSize(ref.fVerbs.size(), ref.fPoints.size(), ref.fConicWeights.size(),
283                       additionalReserveVerbs, additionalReservePoints, additionalReserveConics);
284     fVerbs = ref.fVerbs;
285     fPoints = ref.fPoints;
286     fConicWeights = ref.fConicWeights;
287     fBoundsIsDirty = ref.fBoundsIsDirty;
288     if (!fBoundsIsDirty) {
289         fBounds = ref.fBounds;
290         fIsFinite = ref.fIsFinite;
291     }
292     fSegmentMask = ref.fSegmentMask;
293     fType = ref.fType;
294     fRRectOrOvalIsCCW = ref.fRRectOrOvalIsCCW;
295     fRRectOrOvalStartIdx = ref.fRRectOrOvalStartIdx;
296     fArcOval = ref.fArcOval;
297     fArcStartAngle = ref.fArcStartAngle;
298     fArcSweepAngle = ref.fArcSweepAngle;
299     fArcType = ref.fArcType;
300     SkDEBUGCODE(this->validate();)
301 }
302 
interpolate(const SkPathRef & ending,SkScalar weight,SkPathRef * out) const303 void SkPathRef::interpolate(const SkPathRef& ending, SkScalar weight, SkPathRef* out) const {
304     const SkScalar* inValues = &ending.getPoints()->fX;
305     SkScalar* outValues = &out->getWritablePoints()->fX;
306     int count = out->countPoints() * 2;
307     for (int index = 0; index < count; ++index) {
308         outValues[index] = outValues[index] * weight + inValues[index] * (1 - weight);
309     }
310     out->fBoundsIsDirty = true;
311     out->fType = PathType::kGeneral;
312 }
313 
growForVerbsInPath(const SkPathRef & path)314 std::tuple<SkPoint*, SkScalar*> SkPathRef::growForVerbsInPath(const SkPathRef& path) {
315     SkDEBUGCODE(this->validate();)
316 
317     fSegmentMask |= path.fSegmentMask;
318     fBoundsIsDirty = true;  // this also invalidates fIsFinite
319     fType = PathType::kGeneral;
320 
321     if (int numVerbs = path.countVerbs()) {
322         memcpy(fVerbs.push_back_n(numVerbs), path.fVerbs.begin(), numVerbs * sizeof(fVerbs[0]));
323     }
324 
325     SkPoint* pts = nullptr;
326     if (int numPts = path.countPoints()) {
327         pts = fPoints.push_back_n(numPts);
328     }
329 
330     SkScalar* weights = nullptr;
331     if (int numConics = path.countWeights()) {
332         weights = fConicWeights.push_back_n(numConics);
333     }
334 
335     SkDEBUGCODE(this->validate();)
336     return {pts, weights};
337 }
338 
growForRepeatedVerb(int verb,int numVbs,SkScalar ** weights)339 SkPoint* SkPathRef::growForRepeatedVerb(int /*SkPath::Verb*/ verb,
340                                         int numVbs,
341                                         SkScalar** weights) {
342     SkDEBUGCODE(this->validate();)
343     int pCnt;
344     switch (verb) {
345         case SkPath::kMove_Verb:
346             pCnt = numVbs;
347             break;
348         case SkPath::kLine_Verb:
349             fSegmentMask |= SkPath::kLine_SegmentMask;
350             pCnt = numVbs;
351             break;
352         case SkPath::kQuad_Verb:
353             fSegmentMask |= SkPath::kQuad_SegmentMask;
354             pCnt = 2 * numVbs;
355             break;
356         case SkPath::kConic_Verb:
357             fSegmentMask |= SkPath::kConic_SegmentMask;
358             pCnt = 2 * numVbs;
359             break;
360         case SkPath::kCubic_Verb:
361             fSegmentMask |= SkPath::kCubic_SegmentMask;
362             pCnt = 3 * numVbs;
363             break;
364         case SkPath::kClose_Verb:
365             SkDEBUGFAIL("growForRepeatedVerb called for kClose_Verb");
366             pCnt = 0;
367             break;
368         case SkPath::kDone_Verb:
369             SkDEBUGFAIL("growForRepeatedVerb called for kDone");
370             pCnt = 0;
371             break;
372         default:
373             SkDEBUGFAIL("default should not be reached");
374             pCnt = 0;
375             break;
376     }
377 
378     fBoundsIsDirty = true;  // this also invalidates fIsFinite
379     fType = PathType::kGeneral;
380 
381     memset(fVerbs.push_back_n(numVbs), verb, numVbs);
382     if (SkPath::kConic_Verb == verb) {
383         SkASSERT(weights);
384         *weights = fConicWeights.push_back_n(numVbs);
385     }
386     SkPoint* pts = fPoints.push_back_n(pCnt);
387 
388     SkDEBUGCODE(this->validate();)
389     return pts;
390 }
391 
growForVerb(int verb,SkScalar weight)392 SkPoint* SkPathRef::growForVerb(int /* SkPath::Verb*/ verb, SkScalar weight) {
393     SkDEBUGCODE(this->validate();)
394     int pCnt;
395     unsigned mask = 0;
396     switch (verb) {
397         case SkPath::kMove_Verb:
398             pCnt = 1;
399             break;
400         case SkPath::kLine_Verb:
401             mask = SkPath::kLine_SegmentMask;
402             pCnt = 1;
403             break;
404         case SkPath::kQuad_Verb:
405             mask = SkPath::kQuad_SegmentMask;
406             pCnt = 2;
407             break;
408         case SkPath::kConic_Verb:
409             mask = SkPath::kConic_SegmentMask;
410             pCnt = 2;
411             break;
412         case SkPath::kCubic_Verb:
413             mask = SkPath::kCubic_SegmentMask;
414             pCnt = 3;
415             break;
416         case SkPath::kClose_Verb:
417             pCnt = 0;
418             break;
419         case SkPath::kDone_Verb:
420             SkDEBUGFAIL("growForVerb called for kDone");
421             pCnt = 0;
422             break;
423         default:
424             SkDEBUGFAIL("default is not reached");
425             pCnt = 0;
426             break;
427     }
428 
429     fSegmentMask |= mask;
430     fBoundsIsDirty = true;  // this also invalidates fIsFinite
431     fType = PathType::kGeneral;
432 
433     fVerbs.push_back(verb);
434     if (SkPath::kConic_Verb == verb) {
435         fConicWeights.push_back(weight);
436     }
437     SkPoint* pts = fPoints.push_back_n(pCnt);
438 
439     SkDEBUGCODE(this->validate();)
440     return pts;
441 }
442 
genID(uint8_t fillType) const443 uint32_t SkPathRef::genID(uint8_t fillType) const {
444     SkASSERT(fEditorsAttached.load() == 0);
445     static const uint32_t kMask = (static_cast<int64_t>(1) << kPathRefGenIDBitCnt) - 1;
446 
447     if (fGenerationID == 0) {
448         if (fPoints.empty() && fVerbs.empty()) {
449             fGenerationID = kEmptyGenID;
450         } else {
451             static std::atomic<uint32_t> nextID{kEmptyGenID + 1};
452             do {
453                 fGenerationID = nextID.fetch_add(1, std::memory_order_relaxed) & kMask;
454             } while (fGenerationID == 0 || fGenerationID == kEmptyGenID);
455         }
456     }
457     #if defined(SK_BUILD_FOR_ANDROID_FRAMEWORK)
458         SkASSERT((unsigned)fillType < (1 << (32 - kPathRefGenIDBitCnt)));
459         fGenerationID |= static_cast<uint32_t>(fillType) << kPathRefGenIDBitCnt;
460     #endif
461     return fGenerationID;
462 }
463 
addGenIDChangeListener(sk_sp<SkIDChangeListener> listener)464 void SkPathRef::addGenIDChangeListener(sk_sp<SkIDChangeListener> listener) {
465     if (this == gEmpty) {
466         return;
467     }
468     fGenIDChangeListeners.add(std::move(listener));
469 }
470 
genIDChangeListenerCount()471 int SkPathRef::genIDChangeListenerCount() { return fGenIDChangeListeners.count(); }
472 
473 // we need to be called *before* the genID gets changed or zerod
callGenIDChangeListeners()474 void SkPathRef::callGenIDChangeListeners() {
475     fGenIDChangeListeners.changed();
476 }
477 
getRRect() const478 SkRRect SkPathRef::getRRect() const {
479     const SkRect& bounds = this->getBounds();
480     SkVector radii[4] = {{0, 0}, {0, 0}, {0, 0}, {0, 0}};
481     Iter iter(*this);
482     SkPoint pts[4];
483     uint8_t verb = iter.next(pts);
484     SkASSERT(SkPath::kMove_Verb == verb);
485     while ((verb = iter.next(pts)) != SkPath::kDone_Verb) {
486         if (SkPath::kConic_Verb == verb) {
487             SkVector v1_0 = pts[1] - pts[0];
488             SkVector v2_1 = pts[2] - pts[1];
489             SkVector dxdy;
490             if (v1_0.fX) {
491                 SkASSERT(!v2_1.fX && !v1_0.fY);
492                 dxdy.set(SkScalarAbs(v1_0.fX), SkScalarAbs(v2_1.fY));
493             } else if (!v1_0.fY) {
494                 SkASSERT(!v2_1.fX || !v2_1.fY);
495                 dxdy.set(SkScalarAbs(v2_1.fX), SkScalarAbs(v2_1.fY));
496             } else {
497                 SkASSERT(!v2_1.fY);
498                 dxdy.set(SkScalarAbs(v2_1.fX), SkScalarAbs(v1_0.fY));
499             }
500             SkRRect::Corner corner =
501                     pts[1].fX == bounds.fLeft ?
502                         pts[1].fY == bounds.fTop ?
503                             SkRRect::kUpperLeft_Corner : SkRRect::kLowerLeft_Corner :
504                     pts[1].fY == bounds.fTop ?
505                             SkRRect::kUpperRight_Corner : SkRRect::kLowerRight_Corner;
506             SkASSERT(!radii[corner].fX && !radii[corner].fY);
507             radii[corner] = dxdy;
508         } else {
509             SkASSERT((verb == SkPath::kLine_Verb
510                     && (!(pts[1].fX - pts[0].fX) || !(pts[1].fY - pts[0].fY)))
511                     || verb == SkPath::kClose_Verb);
512         }
513     }
514     SkRRect rrect;
515     rrect.setRectRadii(bounds, radii);
516     return rrect;
517 }
518 
isRRect(SkRRect * rrect,bool * isCCW,unsigned * start) const519 bool SkPathRef::isRRect(SkRRect* rrect, bool* isCCW, unsigned* start) const {
520     if (fType == PathType::kRRect) {
521         if (rrect) {
522             *rrect = this->getRRect();
523         }
524         if (isCCW) {
525             *isCCW = SkToBool(fRRectOrOvalIsCCW);
526         }
527         if (start) {
528             *start = fRRectOrOvalStartIdx;
529         }
530     }
531     return fType == PathType::kRRect;
532 }
533 
534 ///////////////////////////////////////////////////////////////////////////////
535 
Iter()536 SkPathRef::Iter::Iter() {
537 #ifdef SK_DEBUG
538     fPts = nullptr;
539     fConicWeights = nullptr;
540 #endif
541     // need to init enough to make next() harmlessly return kDone_Verb
542     fVerbs = nullptr;
543     fVerbStop = nullptr;
544 }
545 
Iter(const SkPathRef & path)546 SkPathRef::Iter::Iter(const SkPathRef& path) {
547     this->setPathRef(path);
548 }
549 
setPathRef(const SkPathRef & path)550 void SkPathRef::Iter::setPathRef(const SkPathRef& path) {
551     fPts = path.points();
552     fVerbs = path.verbsBegin();
553     fVerbStop = path.verbsEnd();
554     fConicWeights = path.conicWeights();
555     if (fConicWeights) {
556         fConicWeights -= 1;  // begin one behind
557     }
558 
559     // Don't allow iteration through non-finite points.
560     if (!path.isFinite()) {
561         fVerbStop = fVerbs;
562     }
563 }
564 
next(SkPoint pts[4])565 uint8_t SkPathRef::Iter::next(SkPoint pts[4]) {
566     SkASSERT(pts);
567 
568     SkDEBUGCODE(unsigned peekResult = this->peek();)
569 
570     if (fVerbs == fVerbStop) {
571         SkASSERT(peekResult == SkPath::kDone_Verb);
572         return (uint8_t) SkPath::kDone_Verb;
573     }
574 
575     // fVerbs points one beyond next verb so decrement first.
576     unsigned verb = *fVerbs++;
577     const SkPoint* srcPts = fPts;
578 
579     switch (verb) {
580         case SkPath::kMove_Verb:
581             pts[0] = srcPts[0];
582             srcPts += 1;
583             break;
584         case SkPath::kLine_Verb:
585             pts[0] = srcPts[-1];
586             pts[1] = srcPts[0];
587             srcPts += 1;
588             break;
589         case SkPath::kConic_Verb:
590             fConicWeights += 1;
591             [[fallthrough]];
592         case SkPath::kQuad_Verb:
593             pts[0] = srcPts[-1];
594             pts[1] = srcPts[0];
595             pts[2] = srcPts[1];
596             srcPts += 2;
597             break;
598         case SkPath::kCubic_Verb:
599             pts[0] = srcPts[-1];
600             pts[1] = srcPts[0];
601             pts[2] = srcPts[1];
602             pts[3] = srcPts[2];
603             srcPts += 3;
604             break;
605         case SkPath::kClose_Verb:
606             break;
607         case SkPath::kDone_Verb:
608             SkASSERT(fVerbs == fVerbStop);
609             break;
610     }
611     fPts = srcPts;
612     SkASSERT(peekResult == verb);
613     return (uint8_t) verb;
614 }
615 
peek() const616 uint8_t SkPathRef::Iter::peek() const {
617     return fVerbs < fVerbStop ? *fVerbs : (uint8_t) SkPath::kDone_Verb;
618 }
619 
620 
isValid() const621 bool SkPathRef::isValid() const {
622     switch (fType) {
623         case PathType::kGeneral:
624             break;
625         case PathType::kOval:
626             if (fRRectOrOvalStartIdx >= 4) {
627                 return false;
628             }
629             break;
630         case PathType::kRRect:
631             if (fRRectOrOvalStartIdx >= 8) {
632                 return false;
633             }
634             break;
635         case PathType::kArc:
636             if (!(fArcOval.isFinite() && SkIsFinite(fArcStartAngle, fArcSweepAngle))) {
637                 return false;
638             }
639             break;
640     }
641 
642     if (!fBoundsIsDirty && !fBounds.isEmpty()) {
643         bool isFinite = true;
644         auto leftTop = skvx::float2(fBounds.fLeft, fBounds.fTop);
645         auto rightBot = skvx::float2(fBounds.fRight, fBounds.fBottom);
646         for (int i = 0; i < fPoints.size(); ++i) {
647             auto point = skvx::float2(fPoints[i].fX, fPoints[i].fY);
648 #ifdef SK_DEBUG
649             if (fPoints[i].isFinite() && (any(point < leftTop)|| any(point > rightBot))) {
650                 SkDebugf("bad SkPathRef bounds: %g %g %g %g\n",
651                          fBounds.fLeft, fBounds.fTop, fBounds.fRight, fBounds.fBottom);
652                 for (int j = 0; j < fPoints.size(); ++j) {
653                     if (i == j) {
654                         SkDebugf("*** bounds do not contain: ");
655                     }
656                     SkDebugf("%g %g\n", fPoints[j].fX, fPoints[j].fY);
657                 }
658                 return false;
659             }
660 #endif
661 
662             if (fPoints[i].isFinite() && any(point < leftTop) && !any(point > rightBot))
663                 return false;
664             if (!fPoints[i].isFinite()) {
665                 isFinite = false;
666             }
667         }
668         if (SkToBool(fIsFinite) != isFinite) {
669             return false;
670         }
671     }
672     return true;
673 }
674 
reset()675 void SkPathRef::reset() {
676     commonReset();
677     fPoints.clear();
678     fVerbs.clear();
679     fConicWeights.clear();
680     SkDEBUGCODE(validate();)
681 }
682 
dataMatchesVerbs() const683 bool SkPathRef::dataMatchesVerbs() const {
684     const auto info = SkPathPriv::AnalyzeVerbs(fVerbs.begin(), fVerbs.size());
685     return info.valid                          &&
686            info.segmentMask == fSegmentMask    &&
687            info.points      == fPoints.size()  &&
688            info.weights     == fConicWeights.size();
689 }
690