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 "SkBuffer.h"
9 #include "SkOnce.h"
10 #include "SkPath.h"
11 #include "SkPathRef.h"
12 #include <limits>
13 
14 //////////////////////////////////////////////////////////////////////////////
Editor(sk_sp<SkPathRef> * pathRef,int incReserveVerbs,int incReservePoints)15 SkPathRef::Editor::Editor(sk_sp<SkPathRef>* pathRef,
16                           int incReserveVerbs,
17                           int incReservePoints)
18 {
19     if ((*pathRef)->unique()) {
20         (*pathRef)->incReserve(incReserveVerbs, incReservePoints);
21     } else {
22         SkPathRef* copy = new SkPathRef;
23         copy->copy(**pathRef, incReserveVerbs, incReservePoints);
24         pathRef->reset(copy);
25     }
26     fPathRef = pathRef->get();
27     fPathRef->callGenIDChangeListeners();
28     fPathRef->fGenerationID = 0;
29     SkDEBUGCODE(sk_atomic_inc(&fPathRef->fEditorsAttached);)
30 }
31 
32 //////////////////////////////////////////////////////////////////////////////
33 
~SkPathRef()34 SkPathRef::~SkPathRef() {
35     this->callGenIDChangeListeners();
36     SkDEBUGCODE(this->validate();)
37     sk_free(fPoints);
38 
39     SkDEBUGCODE(fPoints = nullptr;)
40     SkDEBUGCODE(fVerbs = nullptr;)
41     SkDEBUGCODE(fVerbCnt = 0x9999999;)
42     SkDEBUGCODE(fPointCnt = 0xAAAAAAA;)
43     SkDEBUGCODE(fPointCnt = 0xBBBBBBB;)
44     SkDEBUGCODE(fGenerationID = 0xEEEEEEEE;)
45     SkDEBUGCODE(fEditorsAttached = 0x7777777;)
46 }
47 
48 static SkPathRef* gEmpty = nullptr;
49 
CreateEmpty()50 SkPathRef* SkPathRef::CreateEmpty() {
51     static SkOnce once;
52     once([]{
53         gEmpty = new SkPathRef;
54         gEmpty->computeBounds();   // Avoids races later to be the first to do this.
55     });
56     return SkRef(gEmpty);
57 }
58 
transform_dir_and_start(const SkMatrix & matrix,bool isRRect,bool * isCCW,unsigned * start)59 static void transform_dir_and_start(const SkMatrix& matrix, bool isRRect, bool* isCCW,
60                                     unsigned* start) {
61     int inStart = *start;
62     int rm = 0;
63     if (isRRect) {
64         // Degenerate rrect indices to oval indices and remember the remainder.
65         // Ovals have one index per side whereas rrects have two.
66         rm = inStart & 0b1;
67         inStart /= 2;
68     }
69     // Is the antidiagonal non-zero (otherwise the diagonal is zero)
70     int antiDiag;
71     // Is the non-zero value in the top row (either kMScaleX or kMSkewX) negative
72     int topNeg;
73     // Are the two non-zero diagonal or antidiagonal values the same sign.
74     int sameSign;
75     if (matrix.get(SkMatrix::kMScaleX) != 0) {
76         antiDiag = 0b00;
77         if (matrix.get(SkMatrix::kMScaleX) > 0) {
78             topNeg = 0b00;
79             sameSign = matrix.get(SkMatrix::kMScaleY) > 0 ? 0b01 : 0b00;
80         } else {
81             topNeg = 0b10;
82             sameSign = matrix.get(SkMatrix::kMScaleY) > 0 ? 0b00 : 0b01;
83         }
84     } else {
85         antiDiag = 0b01;
86         if (matrix.get(SkMatrix::kMSkewX) > 0) {
87             topNeg = 0b00;
88             sameSign = matrix.get(SkMatrix::kMSkewY) > 0 ? 0b01 : 0b00;
89         } else {
90             topNeg = 0b10;
91             sameSign = matrix.get(SkMatrix::kMSkewY) > 0 ? 0b00 : 0b01;
92         }
93     }
94     if (sameSign != antiDiag) {
95         // This is a rotation (and maybe scale). The direction is unchanged.
96         // Trust me on the start computation (or draw yourself some pictures)
97         *start = (inStart + 4 - (topNeg | antiDiag)) % 4;
98         SkASSERT(*start < 4);
99         if (isRRect) {
100             *start = 2 * *start + rm;
101         }
102     } else {
103         // This is a mirror (and maybe scale). The direction is reversed.
104         *isCCW = !*isCCW;
105         // Trust me on the start computation (or draw yourself some pictures)
106         *start = (6 + (topNeg | antiDiag) - inStart) % 4;
107         SkASSERT(*start < 4);
108         if (isRRect) {
109             *start = 2 * *start + (rm ? 0 : 1);
110         }
111     }
112 }
113 
CreateTransformedCopy(sk_sp<SkPathRef> * dst,const SkPathRef & src,const SkMatrix & matrix)114 void SkPathRef::CreateTransformedCopy(sk_sp<SkPathRef>* dst,
115                                       const SkPathRef& src,
116                                       const SkMatrix& matrix) {
117     SkDEBUGCODE(src.validate();)
118     if (matrix.isIdentity()) {
119         if (dst->get() != &src) {
120             src.ref();
121             dst->reset(const_cast<SkPathRef*>(&src));
122             SkDEBUGCODE((*dst)->validate();)
123         }
124         return;
125     }
126 
127     if (!(*dst)->unique()) {
128         dst->reset(new SkPathRef);
129     }
130 
131     if (dst->get() != &src) {
132         (*dst)->resetToSize(src.fVerbCnt, src.fPointCnt, src.fConicWeights.count());
133         sk_careful_memcpy((*dst)->verbsMemWritable(), src.verbsMemBegin(),
134                            src.fVerbCnt * sizeof(uint8_t));
135         (*dst)->fConicWeights = src.fConicWeights;
136     }
137 
138     SkASSERT((*dst)->countPoints() == src.countPoints());
139     SkASSERT((*dst)->countVerbs() == src.countVerbs());
140     SkASSERT((*dst)->fConicWeights.count() == src.fConicWeights.count());
141 
142     // Need to check this here in case (&src == dst)
143     bool canXformBounds = !src.fBoundsIsDirty && matrix.rectStaysRect() && src.countPoints() > 1;
144 
145     matrix.mapPoints((*dst)->fPoints, src.points(), src.fPointCnt);
146 
147     /*
148      *  Here we optimize the bounds computation, by noting if the bounds are
149      *  already known, and if so, we just transform those as well and mark
150      *  them as "known", rather than force the transformed path to have to
151      *  recompute them.
152      *
153      *  Special gotchas if the path is effectively empty (<= 1 point) or
154      *  if it is non-finite. In those cases bounds need to stay empty,
155      *  regardless of the matrix.
156      */
157     if (canXformBounds) {
158         (*dst)->fBoundsIsDirty = false;
159         if (src.fIsFinite) {
160             matrix.mapRect(&(*dst)->fBounds, src.fBounds);
161             if (!((*dst)->fIsFinite = (*dst)->fBounds.isFinite())) {
162                 (*dst)->fBounds.setEmpty();
163             }
164         } else {
165             (*dst)->fIsFinite = false;
166             (*dst)->fBounds.setEmpty();
167         }
168     } else {
169         (*dst)->fBoundsIsDirty = true;
170     }
171 
172     (*dst)->fSegmentMask = src.fSegmentMask;
173 
174     // It's an oval only if it stays a rect.
175     bool rectStaysRect = matrix.rectStaysRect();
176     (*dst)->fIsOval = src.fIsOval && rectStaysRect;
177     (*dst)->fIsRRect = src.fIsRRect && rectStaysRect;
178     if ((*dst)->fIsOval || (*dst)->fIsRRect) {
179         unsigned start = src.fRRectOrOvalStartIdx;
180         bool isCCW = SkToBool(src.fRRectOrOvalIsCCW);
181         transform_dir_and_start(matrix, (*dst)->fIsRRect, &isCCW, &start);
182         (*dst)->fRRectOrOvalIsCCW = isCCW;
183         (*dst)->fRRectOrOvalStartIdx = start;
184     }
185 
186     SkDEBUGCODE((*dst)->validate();)
187 }
188 
189 // Given the verb array, deduce the required number of pts and conics,
190 // or if an invalid verb is encountered, return false.
deduce_pts_conics(const uint8_t verbs[],int vCount,int * ptCountPtr,int * conicCountPtr)191 static bool deduce_pts_conics(const uint8_t verbs[], int vCount, int* ptCountPtr,
192                               int* conicCountPtr) {
193     int ptCount = 0;
194     int conicCount = 0;
195     for (int i = 0; i < vCount; ++i) {
196         switch (verbs[i]) {
197             case SkPath::kMove_Verb:
198             case SkPath::kLine_Verb:
199                 ptCount += 1;
200                 break;
201             case SkPath::kConic_Verb:
202                 conicCount += 1;
203                 // fall-through
204             case SkPath::kQuad_Verb:
205                 ptCount += 2;
206                 break;
207             case SkPath::kCubic_Verb:
208                 ptCount += 3;
209                 break;
210             case SkPath::kClose_Verb:
211                 break;
212             default:
213                 return false;
214         }
215     }
216     *ptCountPtr = ptCount;
217     *conicCountPtr = conicCount;
218     return true;
219 }
220 
CreateFromBuffer(SkRBuffer * buffer)221 SkPathRef* SkPathRef::CreateFromBuffer(SkRBuffer* buffer) {
222     std::unique_ptr<SkPathRef> ref(new SkPathRef);
223 
224     int32_t packed;
225     if (!buffer->readS32(&packed)) {
226         return nullptr;
227     }
228 
229     ref->fIsFinite = (packed >> kIsFinite_SerializationShift) & 1;
230     uint8_t segmentMask = (packed >> kSegmentMask_SerializationShift) & 0xF;
231     bool isOval  = (packed >> kIsOval_SerializationShift) & 1;
232     bool isRRect  = (packed >> kIsRRect_SerializationShift) & 1;
233     if (isOval && isRRect) {
234         // Fuzzing generates data with both oval and rrect flags set; abort early in this case/
235         return nullptr;
236     }
237     bool rrectOrOvalIsCCW = (packed >> kRRectOrOvalIsCCW_SerializationShift) & 1;
238     unsigned rrectOrOvalStartIdx = (packed >> kRRectOrOvalStartIdx_SerializationShift) & 0x7;
239 
240     int32_t verbCount, pointCount, conicCount;
241     ptrdiff_t maxPtrDiff = std::numeric_limits<ptrdiff_t>::max();
242     if (!buffer->readU32(&(ref->fGenerationID)) ||
243         !buffer->readS32(&verbCount) ||
244         verbCount < 0 ||
245         static_cast<uint32_t>(verbCount) > maxPtrDiff/sizeof(uint8_t) ||
246         !buffer->readS32(&pointCount) ||
247         pointCount < 0 ||
248         static_cast<uint32_t>(pointCount) > maxPtrDiff/sizeof(SkPoint) ||
249         sizeof(uint8_t) * verbCount + sizeof(SkPoint) * pointCount >
250             static_cast<size_t>(maxPtrDiff) ||
251         !buffer->readS32(&conicCount) ||
252         conicCount < 0) {
253         return nullptr;
254     }
255 
256     ref->resetToSize(verbCount, pointCount, conicCount);
257     SkASSERT(verbCount == ref->countVerbs());
258     SkASSERT(pointCount == ref->countPoints());
259     SkASSERT(conicCount == ref->fConicWeights.count());
260 
261     if (!buffer->read(ref->verbsMemWritable(), verbCount * sizeof(uint8_t)) ||
262         !buffer->read(ref->fPoints, pointCount * sizeof(SkPoint)) ||
263         !buffer->read(ref->fConicWeights.begin(), conicCount * sizeof(SkScalar)) ||
264         !buffer->read(&ref->fBounds, sizeof(SkRect))) {
265         return nullptr;
266     }
267 
268     // Check that the verbs are valid, and imply the correct number of pts and conics
269     {
270         int pCount, cCount;
271         if (!deduce_pts_conics(ref->verbsMemBegin(), ref->countVerbs(), &pCount, &cCount) ||
272             pCount != ref->countPoints() || cCount != ref->fConicWeights.count()) {
273             return nullptr;
274         }
275         // Check that the bounds match the serialized bounds.
276         SkRect bounds;
277         if (ComputePtBounds(&bounds, *ref) != SkToBool(ref->fIsFinite) || bounds != ref->fBounds) {
278             return nullptr;
279         }
280     }
281 
282     ref->fBoundsIsDirty = false;
283 
284     // resetToSize clears fSegmentMask and fIsOval
285     ref->fSegmentMask = segmentMask;
286     ref->fIsOval = isOval;
287     ref->fIsRRect = isRRect;
288     ref->fRRectOrOvalIsCCW = rrectOrOvalIsCCW;
289     ref->fRRectOrOvalStartIdx = rrectOrOvalStartIdx;
290     return ref.release();
291 }
292 
Rewind(sk_sp<SkPathRef> * pathRef)293 void SkPathRef::Rewind(sk_sp<SkPathRef>* pathRef) {
294     if ((*pathRef)->unique()) {
295         SkDEBUGCODE((*pathRef)->validate();)
296         (*pathRef)->callGenIDChangeListeners();
297         (*pathRef)->fBoundsIsDirty = true;  // this also invalidates fIsFinite
298         (*pathRef)->fVerbCnt = 0;
299         (*pathRef)->fPointCnt = 0;
300         (*pathRef)->fFreeSpace = (*pathRef)->currSize();
301         (*pathRef)->fGenerationID = 0;
302         (*pathRef)->fConicWeights.rewind();
303         (*pathRef)->fSegmentMask = 0;
304         (*pathRef)->fIsOval = false;
305         (*pathRef)->fIsRRect = false;
306         SkDEBUGCODE((*pathRef)->validate();)
307     } else {
308         int oldVCnt = (*pathRef)->countVerbs();
309         int oldPCnt = (*pathRef)->countPoints();
310         pathRef->reset(new SkPathRef);
311         (*pathRef)->resetToSize(0, 0, 0, oldVCnt, oldPCnt);
312     }
313 }
314 
operator ==(const SkPathRef & ref) const315 bool SkPathRef::operator== (const SkPathRef& ref) const {
316     SkDEBUGCODE(this->validate();)
317     SkDEBUGCODE(ref.validate();)
318 
319     // We explicitly check fSegmentMask as a quick-reject. We could skip it,
320     // since it is only a cache of info in the fVerbs, but its a fast way to
321     // notice a difference
322     if (fSegmentMask != ref.fSegmentMask) {
323         return false;
324     }
325 
326     bool genIDMatch = fGenerationID && fGenerationID == ref.fGenerationID;
327 #ifdef SK_RELEASE
328     if (genIDMatch) {
329         return true;
330     }
331 #endif
332     if (fPointCnt != ref.fPointCnt ||
333         fVerbCnt != ref.fVerbCnt) {
334         SkASSERT(!genIDMatch);
335         return false;
336     }
337     if (0 == ref.fVerbCnt) {
338         SkASSERT(0 == ref.fPointCnt);
339         return true;
340     }
341     SkASSERT(this->verbsMemBegin() && ref.verbsMemBegin());
342     if (0 != memcmp(this->verbsMemBegin(),
343                     ref.verbsMemBegin(),
344                     ref.fVerbCnt * sizeof(uint8_t))) {
345         SkASSERT(!genIDMatch);
346         return false;
347     }
348     SkASSERT(this->points() && ref.points());
349     if (0 != memcmp(this->points(),
350                     ref.points(),
351                     ref.fPointCnt * sizeof(SkPoint))) {
352         SkASSERT(!genIDMatch);
353         return false;
354     }
355     if (fConicWeights != ref.fConicWeights) {
356         SkASSERT(!genIDMatch);
357         return false;
358     }
359     return true;
360 }
361 
writeToBuffer(SkWBuffer * buffer) const362 void SkPathRef::writeToBuffer(SkWBuffer* buffer) const {
363     SkDEBUGCODE(this->validate();)
364     SkDEBUGCODE(size_t beforePos = buffer->pos();)
365 
366     // Call getBounds() to ensure (as a side-effect) that fBounds
367     // and fIsFinite are computed.
368     const SkRect& bounds = this->getBounds();
369 
370     int32_t packed = ((fRRectOrOvalStartIdx & 7) << kRRectOrOvalStartIdx_SerializationShift) |
371                      ((fRRectOrOvalIsCCW & 1) << kRRectOrOvalIsCCW_SerializationShift) |
372                      ((fIsFinite & 1) << kIsFinite_SerializationShift) |
373                      ((fIsOval & 1) << kIsOval_SerializationShift) |
374                      ((fIsRRect & 1) << kIsRRect_SerializationShift) |
375                      (fSegmentMask << kSegmentMask_SerializationShift);
376     buffer->write32(packed);
377 
378     // TODO: write gen ID here. Problem: We don't know if we're cross process or not from
379     // SkWBuffer. Until this is fixed we write 0.
380     buffer->write32(0);
381     buffer->write32(fVerbCnt);
382     buffer->write32(fPointCnt);
383     buffer->write32(fConicWeights.count());
384     buffer->write(verbsMemBegin(), fVerbCnt * sizeof(uint8_t));
385     buffer->write(fPoints, fPointCnt * sizeof(SkPoint));
386     buffer->write(fConicWeights.begin(), fConicWeights.bytes());
387     buffer->write(&bounds, sizeof(bounds));
388 
389     SkASSERT(buffer->pos() - beforePos == (size_t) this->writeSize());
390 }
391 
writeSize() const392 uint32_t SkPathRef::writeSize() const {
393     return uint32_t(5 * sizeof(uint32_t) +
394                     fVerbCnt * sizeof(uint8_t) +
395                     fPointCnt * sizeof(SkPoint) +
396                     fConicWeights.bytes() +
397                     sizeof(SkRect));
398 }
399 
copy(const SkPathRef & ref,int additionalReserveVerbs,int additionalReservePoints)400 void SkPathRef::copy(const SkPathRef& ref,
401                      int additionalReserveVerbs,
402                      int additionalReservePoints) {
403     SkDEBUGCODE(this->validate();)
404     this->resetToSize(ref.fVerbCnt, ref.fPointCnt, ref.fConicWeights.count(),
405                         additionalReserveVerbs, additionalReservePoints);
406     sk_careful_memcpy(this->verbsMemWritable(), ref.verbsMemBegin(), ref.fVerbCnt*sizeof(uint8_t));
407     sk_careful_memcpy(this->fPoints, ref.fPoints, ref.fPointCnt * sizeof(SkPoint));
408     fConicWeights = ref.fConicWeights;
409     fBoundsIsDirty = ref.fBoundsIsDirty;
410     if (!fBoundsIsDirty) {
411         fBounds = ref.fBounds;
412         fIsFinite = ref.fIsFinite;
413     }
414     fSegmentMask = ref.fSegmentMask;
415     fIsOval = ref.fIsOval;
416     fIsRRect = ref.fIsRRect;
417     fRRectOrOvalIsCCW = ref.fRRectOrOvalIsCCW;
418     fRRectOrOvalStartIdx = ref.fRRectOrOvalStartIdx;
419     SkDEBUGCODE(this->validate();)
420 }
421 
422 
interpolate(const SkPathRef & ending,SkScalar weight,SkPathRef * out) const423 void SkPathRef::interpolate(const SkPathRef& ending, SkScalar weight, SkPathRef* out) const {
424     const SkScalar* inValues = &ending.getPoints()->fX;
425     SkScalar* outValues = &out->getPoints()->fX;
426     int count = out->countPoints() * 2;
427     for (int index = 0; index < count; ++index) {
428         outValues[index] = outValues[index] * weight + inValues[index] * (1 - weight);
429     }
430     out->fBoundsIsDirty = true;
431     out->fIsOval = false;
432     out->fIsRRect = false;
433 }
434 
growForRepeatedVerb(int verb,int numVbs,SkScalar ** weights)435 SkPoint* SkPathRef::growForRepeatedVerb(int /*SkPath::Verb*/ verb,
436                                         int numVbs,
437                                         SkScalar** weights) {
438     // This value is just made-up for now. When count is 4, calling memset was much
439     // slower than just writing the loop. This seems odd, and hopefully in the
440     // future this will appear to have been a fluke...
441     static const unsigned int kMIN_COUNT_FOR_MEMSET_TO_BE_FAST = 16;
442 
443     SkDEBUGCODE(this->validate();)
444     int pCnt;
445     bool dirtyAfterEdit = true;
446     switch (verb) {
447         case SkPath::kMove_Verb:
448             pCnt = numVbs;
449             dirtyAfterEdit = false;
450             break;
451         case SkPath::kLine_Verb:
452             fSegmentMask |= SkPath::kLine_SegmentMask;
453             pCnt = numVbs;
454             break;
455         case SkPath::kQuad_Verb:
456             fSegmentMask |= SkPath::kQuad_SegmentMask;
457             pCnt = 2 * numVbs;
458             break;
459         case SkPath::kConic_Verb:
460             fSegmentMask |= SkPath::kConic_SegmentMask;
461             pCnt = 2 * numVbs;
462             break;
463         case SkPath::kCubic_Verb:
464             fSegmentMask |= SkPath::kCubic_SegmentMask;
465             pCnt = 3 * numVbs;
466             break;
467         case SkPath::kClose_Verb:
468             SkDEBUGFAIL("growForRepeatedVerb called for kClose_Verb");
469             pCnt = 0;
470             dirtyAfterEdit = false;
471             break;
472         case SkPath::kDone_Verb:
473             SkDEBUGFAIL("growForRepeatedVerb called for kDone");
474             // fall through
475         default:
476             SkDEBUGFAIL("default should not be reached");
477             pCnt = 0;
478             dirtyAfterEdit = false;
479     }
480 
481     size_t space = numVbs * sizeof(uint8_t) + pCnt * sizeof (SkPoint);
482     this->makeSpace(space);
483 
484     SkPoint* ret = fPoints + fPointCnt;
485     uint8_t* vb = fVerbs - fVerbCnt;
486 
487     // cast to unsigned, so if kMIN_COUNT_FOR_MEMSET_TO_BE_FAST is defined to
488     // be 0, the compiler will remove the test/branch entirely.
489     if ((unsigned)numVbs >= kMIN_COUNT_FOR_MEMSET_TO_BE_FAST) {
490         memset(vb - numVbs, verb, numVbs);
491     } else {
492         for (int i = 0; i < numVbs; ++i) {
493             vb[~i] = verb;
494         }
495     }
496 
497     fVerbCnt += numVbs;
498     fPointCnt += pCnt;
499     fFreeSpace -= space;
500     fBoundsIsDirty = true;  // this also invalidates fIsFinite
501     if (dirtyAfterEdit) {
502         fIsOval = false;
503         fIsRRect = false;
504     }
505 
506     if (SkPath::kConic_Verb == verb) {
507         SkASSERT(weights);
508         *weights = fConicWeights.append(numVbs);
509     }
510 
511     SkDEBUGCODE(this->validate();)
512     return ret;
513 }
514 
growForVerb(int verb,SkScalar weight)515 SkPoint* SkPathRef::growForVerb(int /* SkPath::Verb*/ verb, SkScalar weight) {
516     SkDEBUGCODE(this->validate();)
517     int pCnt;
518     bool dirtyAfterEdit = true;
519     switch (verb) {
520         case SkPath::kMove_Verb:
521             pCnt = 1;
522             dirtyAfterEdit = false;
523             break;
524         case SkPath::kLine_Verb:
525             fSegmentMask |= SkPath::kLine_SegmentMask;
526             pCnt = 1;
527             break;
528         case SkPath::kQuad_Verb:
529             fSegmentMask |= SkPath::kQuad_SegmentMask;
530             pCnt = 2;
531             break;
532         case SkPath::kConic_Verb:
533             fSegmentMask |= SkPath::kConic_SegmentMask;
534             pCnt = 2;
535             break;
536         case SkPath::kCubic_Verb:
537             fSegmentMask |= SkPath::kCubic_SegmentMask;
538             pCnt = 3;
539             break;
540         case SkPath::kClose_Verb:
541             pCnt = 0;
542             dirtyAfterEdit = false;
543             break;
544         case SkPath::kDone_Verb:
545             SkDEBUGFAIL("growForVerb called for kDone");
546             // fall through
547         default:
548             SkDEBUGFAIL("default is not reached");
549             dirtyAfterEdit = false;
550             pCnt = 0;
551     }
552     size_t space = sizeof(uint8_t) + pCnt * sizeof (SkPoint);
553     this->makeSpace(space);
554     this->fVerbs[~fVerbCnt] = verb;
555     SkPoint* ret = fPoints + fPointCnt;
556     fVerbCnt += 1;
557     fPointCnt += pCnt;
558     fFreeSpace -= space;
559     fBoundsIsDirty = true;  // this also invalidates fIsFinite
560     if (dirtyAfterEdit) {
561         fIsOval = false;
562         fIsRRect = false;
563     }
564 
565     if (SkPath::kConic_Verb == verb) {
566         *fConicWeights.append() = weight;
567     }
568 
569     SkDEBUGCODE(this->validate();)
570     return ret;
571 }
572 
genID() const573 uint32_t SkPathRef::genID() const {
574     SkASSERT(!fEditorsAttached);
575     static const uint32_t kMask = (static_cast<int64_t>(1) << SkPath::kPathRefGenIDBitCnt) - 1;
576     if (!fGenerationID) {
577         if (0 == fPointCnt && 0 == fVerbCnt) {
578             fGenerationID = kEmptyGenID;
579         } else {
580             static int32_t  gPathRefGenerationID;
581             // do a loop in case our global wraps around, as we never want to return a 0 or the
582             // empty ID
583             do {
584                 fGenerationID = (sk_atomic_inc(&gPathRefGenerationID) + 1) & kMask;
585             } while (fGenerationID <= kEmptyGenID);
586         }
587     }
588     return fGenerationID;
589 }
590 
addGenIDChangeListener(GenIDChangeListener * listener)591 void SkPathRef::addGenIDChangeListener(GenIDChangeListener* listener) {
592     if (nullptr == listener || this == gEmpty) {
593         delete listener;
594         return;
595     }
596     *fGenIDChangeListeners.append() = listener;
597 }
598 
599 // we need to be called *before* the genID gets changed or zerod
callGenIDChangeListeners()600 void SkPathRef::callGenIDChangeListeners() {
601     for (int i = 0; i < fGenIDChangeListeners.count(); i++) {
602         fGenIDChangeListeners[i]->onChange();
603     }
604 
605     // Listeners get at most one shot, so whether these triggered or not, blow them away.
606     fGenIDChangeListeners.deleteAll();
607 }
608 
getRRect() const609 SkRRect SkPathRef::getRRect() const {
610     const SkRect& bounds = this->getBounds();
611     SkVector radii[4] = {{0, 0}, {0, 0}, {0, 0}, {0, 0}};
612     Iter iter(*this);
613     SkPoint pts[4];
614     uint8_t verb = iter.next(pts);
615     SkASSERT(SkPath::kMove_Verb == verb);
616     while ((verb = iter.next(pts)) != SkPath::kDone_Verb) {
617         if (SkPath::kConic_Verb == verb) {
618             SkVector v1_0 = pts[1] - pts[0];
619             SkVector v2_1 = pts[2] - pts[1];
620             SkVector dxdy;
621             if (v1_0.fX) {
622                 SkASSERT(!v2_1.fX && !v1_0.fY);
623                 dxdy.set(SkScalarAbs(v1_0.fX), SkScalarAbs(v2_1.fY));
624             } else if (!v1_0.fY) {
625                 SkASSERT(!v2_1.fX || !v2_1.fY);
626                 dxdy.set(SkScalarAbs(v2_1.fX), SkScalarAbs(v2_1.fY));
627             } else {
628                 SkASSERT(!v2_1.fY);
629                 dxdy.set(SkScalarAbs(v2_1.fX), SkScalarAbs(v1_0.fY));
630             }
631             SkRRect::Corner corner =
632                     pts[1].fX == bounds.fLeft ?
633                         pts[1].fY == bounds.fTop ?
634                             SkRRect::kUpperLeft_Corner : SkRRect::kLowerLeft_Corner :
635                     pts[1].fY == bounds.fTop ?
636                             SkRRect::kUpperRight_Corner : SkRRect::kLowerRight_Corner;
637             SkASSERT(!radii[corner].fX && !radii[corner].fY);
638             radii[corner] = dxdy;
639         } else {
640             SkASSERT((verb == SkPath::kLine_Verb
641                     && (!(pts[1].fX - pts[0].fX) || !(pts[1].fY - pts[0].fY)))
642                     || verb == SkPath::kClose_Verb);
643         }
644     }
645     SkRRect rrect;
646     rrect.setRectRadii(bounds, radii);
647     return rrect;
648 }
649 
650 ///////////////////////////////////////////////////////////////////////////////
651 
Iter()652 SkPathRef::Iter::Iter() {
653 #ifdef SK_DEBUG
654     fPts = nullptr;
655     fConicWeights = nullptr;
656 #endif
657     // need to init enough to make next() harmlessly return kDone_Verb
658     fVerbs = nullptr;
659     fVerbStop = nullptr;
660 }
661 
Iter(const SkPathRef & path)662 SkPathRef::Iter::Iter(const SkPathRef& path) {
663     this->setPathRef(path);
664 }
665 
setPathRef(const SkPathRef & path)666 void SkPathRef::Iter::setPathRef(const SkPathRef& path) {
667     fPts = path.points();
668     fVerbs = path.verbs();
669     fVerbStop = path.verbsMemBegin();
670     fConicWeights = path.conicWeights();
671     if (fConicWeights) {
672       fConicWeights -= 1;  // begin one behind
673     }
674 }
675 
next(SkPoint pts[4])676 uint8_t SkPathRef::Iter::next(SkPoint pts[4]) {
677     SkASSERT(pts);
678     if (fVerbs == fVerbStop) {
679         return (uint8_t) SkPath::kDone_Verb;
680     }
681 
682     // fVerbs points one beyond next verb so decrement first.
683     unsigned verb = *(--fVerbs);
684     const SkPoint* srcPts = fPts;
685 
686     switch (verb) {
687         case SkPath::kMove_Verb:
688             pts[0] = srcPts[0];
689             srcPts += 1;
690             break;
691         case SkPath::kLine_Verb:
692             pts[0] = srcPts[-1];
693             pts[1] = srcPts[0];
694             srcPts += 1;
695             break;
696         case SkPath::kConic_Verb:
697             fConicWeights += 1;
698             // fall-through
699         case SkPath::kQuad_Verb:
700             pts[0] = srcPts[-1];
701             pts[1] = srcPts[0];
702             pts[2] = srcPts[1];
703             srcPts += 2;
704             break;
705         case SkPath::kCubic_Verb:
706             pts[0] = srcPts[-1];
707             pts[1] = srcPts[0];
708             pts[2] = srcPts[1];
709             pts[3] = srcPts[2];
710             srcPts += 3;
711             break;
712         case SkPath::kClose_Verb:
713             break;
714         case SkPath::kDone_Verb:
715             SkASSERT(fVerbs == fVerbStop);
716             break;
717     }
718     fPts = srcPts;
719     return (uint8_t) verb;
720 }
721 
peek() const722 uint8_t SkPathRef::Iter::peek() const {
723     const uint8_t* next = fVerbs - 1;
724     return next <= fVerbStop ? (uint8_t) SkPath::kDone_Verb : *next;
725 }
726 
727 #ifdef SK_DEBUG
728 
729 #include "SkNx.h"
730 
validate() const731 void SkPathRef::validate() const {
732     SkASSERT(static_cast<ptrdiff_t>(fFreeSpace) >= 0);
733     SkASSERT(reinterpret_cast<intptr_t>(fVerbs) - reinterpret_cast<intptr_t>(fPoints) >= 0);
734     SkASSERT((nullptr == fPoints) == (nullptr == fVerbs));
735     SkASSERT(!(nullptr == fPoints && 0 != fFreeSpace));
736     SkASSERT(!(nullptr == fPoints && 0 != fFreeSpace));
737     SkASSERT(!(nullptr == fPoints && fPointCnt));
738     SkASSERT(!(nullptr == fVerbs && fVerbCnt));
739     SkASSERT(this->currSize() ==
740                 fFreeSpace + sizeof(SkPoint) * fPointCnt + sizeof(uint8_t) * fVerbCnt);
741 
742     if (fIsOval || fIsRRect) {
743         // Currently we don't allow both of these to be set, even though ovals are round rects.
744         SkASSERT(fIsOval != fIsRRect);
745         if (fIsOval) {
746             SkASSERT(fRRectOrOvalStartIdx < 4);
747         } else {
748             SkASSERT(fRRectOrOvalStartIdx < 8);
749         }
750     }
751 
752     if (!fBoundsIsDirty && !fBounds.isEmpty()) {
753         bool isFinite = true;
754         Sk2s leftTop = Sk2s(fBounds.fLeft, fBounds.fTop);
755         Sk2s rightBot = Sk2s(fBounds.fRight, fBounds.fBottom);
756         for (int i = 0; i < fPointCnt; ++i) {
757             Sk2s point = Sk2s(fPoints[i].fX, fPoints[i].fY);
758 #ifdef SK_DEBUG
759             if (fPoints[i].isFinite() &&
760                 ((point < leftTop).anyTrue() || (point > rightBot).anyTrue())) {
761                 SkDebugf("bounds: %f %f %f %f\n",
762                          fBounds.fLeft, fBounds.fTop, fBounds.fRight, fBounds.fBottom);
763                 for (int j = 0; j < fPointCnt; ++j) {
764                     if (i == j) {
765                         SkDebugf("*");
766                     }
767                     SkDebugf("%f %f\n", fPoints[j].fX, fPoints[j].fY);
768                 }
769             }
770 #endif
771 
772             SkASSERT(!fPoints[i].isFinite() ||
773                     (!(point < leftTop).anyTrue() && !(point > rightBot).anyTrue()));
774             if (!fPoints[i].isFinite()) {
775                 isFinite = false;
776             }
777         }
778         SkASSERT(SkToBool(fIsFinite) == isFinite);
779     }
780 
781 #ifdef SK_DEBUG_PATH
782     uint32_t mask = 0;
783     for (int i = 0; i < fVerbCnt; ++i) {
784         switch (fVerbs[~i]) {
785             case SkPath::kMove_Verb:
786                 break;
787             case SkPath::kLine_Verb:
788                 mask |= SkPath::kLine_SegmentMask;
789                 break;
790             case SkPath::kQuad_Verb:
791                 mask |= SkPath::kQuad_SegmentMask;
792                 break;
793             case SkPath::kConic_Verb:
794                 mask |= SkPath::kConic_SegmentMask;
795                 break;
796             case SkPath::kCubic_Verb:
797                 mask |= SkPath::kCubic_SegmentMask;
798                 break;
799             case SkPath::kClose_Verb:
800                 break;
801             case SkPath::kDone_Verb:
802                 SkDEBUGFAIL("Done verb shouldn't be recorded.");
803                 break;
804             default:
805                 SkDEBUGFAIL("Unknown Verb");
806                 break;
807         }
808     }
809     SkASSERT(mask == fSegmentMask);
810 #endif // SK_DEBUG_PATH
811 }
812 #endif
813