| /* |
| * Copyright 2012 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| #include "SkOpCoincidence.h" |
| #include "SkOpContour.h" |
| #include "SkOpSegment.h" |
| #include "SkPathWriter.h" |
| |
| /* |
| After computing raw intersections, post process all segments to: |
| - find small collections of points that can be collapsed to a single point |
| - find missing intersections to resolve differences caused by different algorithms |
| |
| Consider segments containing tiny or small intervals. Consider coincident segments |
| because coincidence finds intersections through distance measurement that non-coincident |
| intersection tests cannot. |
| */ |
| |
| #define F (false) // discard the edge |
| #define T (true) // keep the edge |
| |
| static const bool gUnaryActiveEdge[2][2] = { |
| // from=0 from=1 |
| // to=0,1 to=0,1 |
| {F, T}, {T, F}, |
| }; |
| |
| static const bool gActiveEdge[kXOR_SkPathOp + 1][2][2][2][2] = { |
| // miFrom=0 miFrom=1 |
| // miTo=0 miTo=1 miTo=0 miTo=1 |
| // suFrom=0 1 suFrom=0 1 suFrom=0 1 suFrom=0 1 |
| // suTo=0,1 suTo=0,1 suTo=0,1 suTo=0,1 suTo=0,1 suTo=0,1 suTo=0,1 suTo=0,1 |
| {{{{F, F}, {F, F}}, {{T, F}, {T, F}}}, {{{T, T}, {F, F}}, {{F, T}, {T, F}}}}, // mi - su |
| {{{{F, F}, {F, F}}, {{F, T}, {F, T}}}, {{{F, F}, {T, T}}, {{F, T}, {T, F}}}}, // mi & su |
| {{{{F, T}, {T, F}}, {{T, T}, {F, F}}}, {{{T, F}, {T, F}}, {{F, F}, {F, F}}}}, // mi | su |
| {{{{F, T}, {T, F}}, {{T, F}, {F, T}}}, {{{T, F}, {F, T}}, {{F, T}, {T, F}}}}, // mi ^ su |
| }; |
| |
| #undef F |
| #undef T |
| |
| SkOpAngle* SkOpSegment::activeAngle(SkOpSpanBase* start, SkOpSpanBase** startPtr, |
| SkOpSpanBase** endPtr, bool* done) { |
| if (SkOpAngle* result = activeAngleInner(start, startPtr, endPtr, done)) { |
| return result; |
| } |
| if (SkOpAngle* result = activeAngleOther(start, startPtr, endPtr, done)) { |
| return result; |
| } |
| return nullptr; |
| } |
| |
| SkOpAngle* SkOpSegment::activeAngleInner(SkOpSpanBase* start, SkOpSpanBase** startPtr, |
| SkOpSpanBase** endPtr, bool* done) { |
| SkOpSpan* upSpan = start->upCastable(); |
| if (upSpan) { |
| if (upSpan->windValue() || upSpan->oppValue()) { |
| SkOpSpanBase* next = upSpan->next(); |
| if (!*endPtr) { |
| *startPtr = start; |
| *endPtr = next; |
| } |
| if (!upSpan->done()) { |
| if (upSpan->windSum() != SK_MinS32) { |
| return spanToAngle(start, next); |
| } |
| *done = false; |
| } |
| } else { |
| SkASSERT(upSpan->done()); |
| } |
| } |
| SkOpSpan* downSpan = start->prev(); |
| // edge leading into junction |
| if (downSpan) { |
| if (downSpan->windValue() || downSpan->oppValue()) { |
| if (!*endPtr) { |
| *startPtr = start; |
| *endPtr = downSpan; |
| } |
| if (!downSpan->done()) { |
| if (downSpan->windSum() != SK_MinS32) { |
| return spanToAngle(start, downSpan); |
| } |
| *done = false; |
| } |
| } else { |
| SkASSERT(downSpan->done()); |
| } |
| } |
| return nullptr; |
| } |
| |
| SkOpAngle* SkOpSegment::activeAngleOther(SkOpSpanBase* start, SkOpSpanBase** startPtr, |
| SkOpSpanBase** endPtr, bool* done) { |
| SkOpPtT* oPtT = start->ptT()->next(); |
| SkOpSegment* other = oPtT->segment(); |
| SkOpSpanBase* oSpan = oPtT->span(); |
| return other->activeAngleInner(oSpan, startPtr, endPtr, done); |
| } |
| |
| bool SkOpSegment::activeOp(SkOpSpanBase* start, SkOpSpanBase* end, int xorMiMask, int xorSuMask, |
| SkPathOp op) { |
| int sumMiWinding = this->updateWinding(end, start); |
| int sumSuWinding = this->updateOppWinding(end, start); |
| #if DEBUG_LIMIT_WIND_SUM |
| SkASSERT(abs(sumMiWinding) <= DEBUG_LIMIT_WIND_SUM); |
| SkASSERT(abs(sumSuWinding) <= DEBUG_LIMIT_WIND_SUM); |
| #endif |
| if (this->operand()) { |
| SkTSwap<int>(sumMiWinding, sumSuWinding); |
| } |
| return this->activeOp(xorMiMask, xorSuMask, start, end, op, &sumMiWinding, &sumSuWinding); |
| } |
| |
| bool SkOpSegment::activeOp(int xorMiMask, int xorSuMask, SkOpSpanBase* start, SkOpSpanBase* end, |
| SkPathOp op, int* sumMiWinding, int* sumSuWinding) { |
| int maxWinding, sumWinding, oppMaxWinding, oppSumWinding; |
| this->setUpWindings(start, end, sumMiWinding, sumSuWinding, |
| &maxWinding, &sumWinding, &oppMaxWinding, &oppSumWinding); |
| bool miFrom; |
| bool miTo; |
| bool suFrom; |
| bool suTo; |
| if (operand()) { |
| miFrom = (oppMaxWinding & xorMiMask) != 0; |
| miTo = (oppSumWinding & xorMiMask) != 0; |
| suFrom = (maxWinding & xorSuMask) != 0; |
| suTo = (sumWinding & xorSuMask) != 0; |
| } else { |
| miFrom = (maxWinding & xorMiMask) != 0; |
| miTo = (sumWinding & xorMiMask) != 0; |
| suFrom = (oppMaxWinding & xorSuMask) != 0; |
| suTo = (oppSumWinding & xorSuMask) != 0; |
| } |
| bool result = gActiveEdge[op][miFrom][miTo][suFrom][suTo]; |
| #if DEBUG_ACTIVE_OP |
| SkDebugf("%s id=%d t=%1.9g tEnd=%1.9g op=%s miFrom=%d miTo=%d suFrom=%d suTo=%d result=%d\n", |
| __FUNCTION__, debugID(), start->t(), end->t(), |
| SkPathOpsDebug::kPathOpStr[op], miFrom, miTo, suFrom, suTo, result); |
| #endif |
| return result; |
| } |
| |
| bool SkOpSegment::activeWinding(SkOpSpanBase* start, SkOpSpanBase* end) { |
| int sumWinding = updateWinding(end, start); |
| return activeWinding(start, end, &sumWinding); |
| } |
| |
| bool SkOpSegment::activeWinding(SkOpSpanBase* start, SkOpSpanBase* end, int* sumWinding) { |
| int maxWinding; |
| setUpWinding(start, end, &maxWinding, sumWinding); |
| bool from = maxWinding != 0; |
| bool to = *sumWinding != 0; |
| bool result = gUnaryActiveEdge[from][to]; |
| return result; |
| } |
| |
| void SkOpSegment::addAlignIntersection(SkOpPtT& endPtT, SkPoint& oldPt, |
| SkOpContourHead* contourList, SkChunkAlloc* allocator) { |
| const SkPoint& newPt = endPtT.fPt; |
| if (newPt == oldPt) { |
| return; |
| } |
| SkPoint line[2] = { newPt, oldPt }; |
| SkPathOpsBounds lineBounds; |
| lineBounds.setBounds(line, 2); |
| SkDLine aLine; |
| aLine.set(line); |
| SkOpContour* current = contourList; |
| do { |
| if (!SkPathOpsBounds::Intersects(current->bounds(), lineBounds)) { |
| continue; |
| } |
| SkOpSegment* segment = current->first(); |
| do { |
| if (!SkPathOpsBounds::Intersects(segment->bounds(), lineBounds)) { |
| continue; |
| } |
| if (newPt == segment->fPts[0]) { |
| continue; |
| } |
| if (newPt == segment->fPts[SkPathOpsVerbToPoints(segment->fVerb)]) { |
| continue; |
| } |
| if (oldPt == segment->fPts[0]) { |
| continue; |
| } |
| if (oldPt == segment->fPts[SkPathOpsVerbToPoints(segment->fVerb)]) { |
| continue; |
| } |
| if (endPtT.contains(segment)) { |
| continue; |
| } |
| SkIntersections i; |
| switch (segment->fVerb) { |
| case SkPath::kLine_Verb: { |
| SkDLine bLine; |
| bLine.set(segment->fPts); |
| i.intersect(bLine, aLine); |
| } break; |
| case SkPath::kQuad_Verb: { |
| SkDQuad bQuad; |
| bQuad.set(segment->fPts); |
| i.intersect(bQuad, aLine); |
| } break; |
| case SkPath::kConic_Verb: { |
| SkDConic bConic; |
| bConic.set(segment->fPts, segment->fWeight); |
| i.intersect(bConic, aLine); |
| } break; |
| case SkPath::kCubic_Verb: { |
| SkDCubic bCubic; |
| bCubic.set(segment->fPts); |
| i.intersect(bCubic, aLine); |
| } break; |
| default: |
| SkASSERT(0); |
| } |
| if (i.used()) { |
| SkASSERT(i.used() == 1); |
| SkASSERT(!zero_or_one(i[0][0])); |
| SkOpSpanBase* checkSpan = fHead.next(); |
| while (!checkSpan->final()) { |
| if (checkSpan->contains(segment)) { |
| goto nextSegment; |
| } |
| checkSpan = checkSpan->upCast()->next(); |
| } |
| SkOpPtT* ptT = segment->addT(i[0][0], SkOpSegment::kAllowAlias, allocator); |
| ptT->fPt = newPt; |
| endPtT.addOpp(ptT); |
| } |
| nextSegment: |
| ; |
| } while ((segment = segment->next())); |
| } while ((current = current->next())); |
| } |
| |
| bool SkOpSegment::addCurveTo(const SkOpSpanBase* start, const SkOpSpanBase* end, |
| SkPathWriter* path) const { |
| if (start->starter(end)->alreadyAdded()) { |
| return false; |
| } |
| SkOpCurve edge; |
| const SkPoint* ePtr; |
| SkScalar eWeight; |
| if ((start == &fHead && end == &fTail) || (start == &fTail && end == &fHead)) { |
| ePtr = fPts; |
| eWeight = fWeight; |
| } else { |
| // OPTIMIZE? if not active, skip remainder and return xyAtT(end) |
| subDivide(start, end, &edge); |
| ePtr = edge.fPts; |
| eWeight = edge.fWeight; |
| } |
| bool reverse = ePtr == fPts && start != &fHead; |
| if (reverse) { |
| path->deferredMoveLine(ePtr[SkPathOpsVerbToPoints(fVerb)]); |
| switch (fVerb) { |
| case SkPath::kLine_Verb: |
| path->deferredLine(ePtr[0]); |
| break; |
| case SkPath::kQuad_Verb: |
| path->quadTo(ePtr[1], ePtr[0]); |
| break; |
| case SkPath::kConic_Verb: |
| path->conicTo(ePtr[1], ePtr[0], eWeight); |
| break; |
| case SkPath::kCubic_Verb: |
| path->cubicTo(ePtr[2], ePtr[1], ePtr[0]); |
| break; |
| default: |
| SkASSERT(0); |
| } |
| } else { |
| path->deferredMoveLine(ePtr[0]); |
| switch (fVerb) { |
| case SkPath::kLine_Verb: |
| path->deferredLine(ePtr[1]); |
| break; |
| case SkPath::kQuad_Verb: |
| path->quadTo(ePtr[1], ePtr[2]); |
| break; |
| case SkPath::kConic_Verb: |
| path->conicTo(ePtr[1], ePtr[2], eWeight); |
| break; |
| case SkPath::kCubic_Verb: |
| path->cubicTo(ePtr[1], ePtr[2], ePtr[3]); |
| break; |
| default: |
| SkASSERT(0); |
| } |
| } |
| return true; |
| } |
| |
| SkOpPtT* SkOpSegment::addMissing(double t, SkOpSegment* opp, SkChunkAlloc* allocator) { |
| SkOpSpanBase* existing = nullptr; |
| SkOpSpanBase* test = &fHead; |
| double testT; |
| do { |
| if ((testT = test->ptT()->fT) >= t) { |
| if (testT == t) { |
| existing = test; |
| } |
| break; |
| } |
| } while ((test = test->upCast()->next())); |
| SkOpPtT* result; |
| if (existing && existing->contains(opp)) { |
| result = existing->ptT(); |
| } else { |
| result = this->addT(t, SkOpSegment::kNoAlias, allocator); |
| } |
| SkASSERT(result); |
| return result; |
| } |
| |
| SkOpPtT* SkOpSegment::addT(double t, AllowAlias allowAlias, SkChunkAlloc* allocator) { |
| debugValidate(); |
| SkPoint pt = this->ptAtT(t); |
| SkOpSpanBase* span = &fHead; |
| do { |
| SkOpPtT* result = span->ptT(); |
| SkOpPtT* loop; |
| bool duplicatePt; |
| if (t == result->fT) { |
| goto bumpSpan; |
| } |
| if (this->match(result, this, t, pt)) { |
| // see if any existing alias matches segment, pt, and t |
| loop = result->next(); |
| duplicatePt = false; |
| while (loop != result) { |
| bool ptMatch = loop->fPt == pt; |
| if (loop->segment() == this && loop->fT == t && ptMatch) { |
| goto bumpSpan; |
| } |
| duplicatePt |= ptMatch; |
| loop = loop->next(); |
| } |
| if (kNoAlias == allowAlias) { |
| bumpSpan: |
| span->bumpSpanAdds(); |
| return result; |
| } |
| SkOpPtT* alias = SkOpTAllocator<SkOpPtT>::Allocate(allocator); |
| alias->init(result->span(), t, pt, duplicatePt); |
| result->insert(alias); |
| result->span()->unaligned(); |
| this->debugValidate(); |
| #if DEBUG_ADD_T |
| SkDebugf("%s alias t=%1.9g segID=%d spanID=%d\n", __FUNCTION__, t, |
| alias->segment()->debugID(), alias->span()->debugID()); |
| #endif |
| span->bumpSpanAdds(); |
| return alias; |
| } |
| if (t < result->fT) { |
| SkOpSpan* prev = result->span()->prev(); |
| if (!prev) { |
| return nullptr; |
| } |
| SkOpSpan* span = insert(prev, allocator); |
| span->init(this, prev, t, pt); |
| this->debugValidate(); |
| #if DEBUG_ADD_T |
| SkDebugf("%s insert t=%1.9g segID=%d spanID=%d\n", __FUNCTION__, t, |
| span->segment()->debugID(), span->debugID()); |
| #endif |
| span->bumpSpanAdds(); |
| return span->ptT(); |
| } |
| SkASSERT(span != &fTail); |
| } while ((span = span->upCast()->next())); |
| SkASSERT(0); |
| return nullptr; |
| } |
| |
| // choose a solitary t and pt value; remove aliases; align the opposite ends |
| void SkOpSegment::align() { |
| debugValidate(); |
| SkOpSpanBase* span = &fHead; |
| if (!span->aligned()) { |
| span->alignEnd(0, fPts[0]); |
| } |
| while ((span = span->upCast()->next())) { |
| if (span == &fTail) { |
| break; |
| } |
| span->align(); |
| } |
| if (!span->aligned()) { |
| span->alignEnd(1, fPts[SkPathOpsVerbToPoints(fVerb)]); |
| } |
| if (this->collapsed()) { |
| SkOpSpan* span = &fHead; |
| do { |
| span->setWindValue(0); |
| span->setOppValue(0); |
| this->markDone(span); |
| } while ((span = span->next()->upCastable())); |
| } |
| debugValidate(); |
| } |
| |
| void SkOpSegment::calcAngles(SkChunkAlloc* allocator) { |
| bool activePrior = !fHead.isCanceled(); |
| if (activePrior && !fHead.simple()) { |
| addStartSpan(allocator); |
| } |
| SkOpSpan* prior = &fHead; |
| SkOpSpanBase* spanBase = fHead.next(); |
| while (spanBase != &fTail) { |
| if (activePrior) { |
| SkOpAngle* priorAngle = SkOpTAllocator<SkOpAngle>::Allocate(allocator); |
| priorAngle->set(spanBase, prior); |
| spanBase->setFromAngle(priorAngle); |
| } |
| SkOpSpan* span = spanBase->upCast(); |
| bool active = !span->isCanceled(); |
| SkOpSpanBase* next = span->next(); |
| if (active) { |
| SkOpAngle* angle = SkOpTAllocator<SkOpAngle>::Allocate(allocator); |
| angle->set(span, next); |
| span->setToAngle(angle); |
| } |
| activePrior = active; |
| prior = span; |
| spanBase = next; |
| } |
| if (activePrior && !fTail.simple()) { |
| addEndSpan(allocator); |
| } |
| } |
| |
| bool SkOpSegment::collapsed() const { |
| return fVerb == SkPath::kLine_Verb && fHead.pt() == fTail.pt(); |
| } |
| |
| void SkOpSegment::ComputeOneSum(const SkOpAngle* baseAngle, SkOpAngle* nextAngle, |
| SkOpAngle::IncludeType includeType) { |
| SkOpSegment* baseSegment = baseAngle->segment(); |
| int sumMiWinding = baseSegment->updateWindingReverse(baseAngle); |
| int sumSuWinding; |
| bool binary = includeType >= SkOpAngle::kBinarySingle; |
| if (binary) { |
| sumSuWinding = baseSegment->updateOppWindingReverse(baseAngle); |
| if (baseSegment->operand()) { |
| SkTSwap<int>(sumMiWinding, sumSuWinding); |
| } |
| } |
| SkOpSegment* nextSegment = nextAngle->segment(); |
| int maxWinding, sumWinding; |
| SkOpSpanBase* last; |
| if (binary) { |
| int oppMaxWinding, oppSumWinding; |
| nextSegment->setUpWindings(nextAngle->start(), nextAngle->end(), &sumMiWinding, |
| &sumSuWinding, &maxWinding, &sumWinding, &oppMaxWinding, &oppSumWinding); |
| last = nextSegment->markAngle(maxWinding, sumWinding, oppMaxWinding, oppSumWinding, |
| nextAngle); |
| } else { |
| nextSegment->setUpWindings(nextAngle->start(), nextAngle->end(), &sumMiWinding, |
| &maxWinding, &sumWinding); |
| last = nextSegment->markAngle(maxWinding, sumWinding, nextAngle); |
| } |
| nextAngle->setLastMarked(last); |
| } |
| |
| void SkOpSegment::ComputeOneSumReverse(SkOpAngle* baseAngle, SkOpAngle* nextAngle, |
| SkOpAngle::IncludeType includeType) { |
| SkOpSegment* baseSegment = baseAngle->segment(); |
| int sumMiWinding = baseSegment->updateWinding(baseAngle); |
| int sumSuWinding; |
| bool binary = includeType >= SkOpAngle::kBinarySingle; |
| if (binary) { |
| sumSuWinding = baseSegment->updateOppWinding(baseAngle); |
| if (baseSegment->operand()) { |
| SkTSwap<int>(sumMiWinding, sumSuWinding); |
| } |
| } |
| SkOpSegment* nextSegment = nextAngle->segment(); |
| int maxWinding, sumWinding; |
| SkOpSpanBase* last; |
| if (binary) { |
| int oppMaxWinding, oppSumWinding; |
| nextSegment->setUpWindings(nextAngle->end(), nextAngle->start(), &sumMiWinding, |
| &sumSuWinding, &maxWinding, &sumWinding, &oppMaxWinding, &oppSumWinding); |
| last = nextSegment->markAngle(maxWinding, sumWinding, oppMaxWinding, oppSumWinding, |
| nextAngle); |
| } else { |
| nextSegment->setUpWindings(nextAngle->end(), nextAngle->start(), &sumMiWinding, |
| &maxWinding, &sumWinding); |
| last = nextSegment->markAngle(maxWinding, sumWinding, nextAngle); |
| } |
| nextAngle->setLastMarked(last); |
| } |
| |
| // at this point, the span is already ordered, or unorderable |
| int SkOpSegment::computeSum(SkOpSpanBase* start, SkOpSpanBase* end, |
| SkOpAngle::IncludeType includeType) { |
| SkASSERT(includeType != SkOpAngle::kUnaryXor); |
| SkOpAngle* firstAngle = this->spanToAngle(end, start); |
| if (nullptr == firstAngle || nullptr == firstAngle->next()) { |
| return SK_NaN32; |
| } |
| // if all angles have a computed winding, |
| // or if no adjacent angles are orderable, |
| // or if adjacent orderable angles have no computed winding, |
| // there's nothing to do |
| // if two orderable angles are adjacent, and both are next to orderable angles, |
| // and one has winding computed, transfer to the other |
| SkOpAngle* baseAngle = nullptr; |
| bool tryReverse = false; |
| // look for counterclockwise transfers |
| SkOpAngle* angle = firstAngle->previous(); |
| SkOpAngle* next = angle->next(); |
| firstAngle = next; |
| do { |
| SkOpAngle* prior = angle; |
| angle = next; |
| next = angle->next(); |
| SkASSERT(prior->next() == angle); |
| SkASSERT(angle->next() == next); |
| if (prior->unorderable() || angle->unorderable() || next->unorderable()) { |
| baseAngle = nullptr; |
| continue; |
| } |
| int testWinding = angle->starter()->windSum(); |
| if (SK_MinS32 != testWinding) { |
| baseAngle = angle; |
| tryReverse = true; |
| continue; |
| } |
| if (baseAngle) { |
| ComputeOneSum(baseAngle, angle, includeType); |
| baseAngle = SK_MinS32 != angle->starter()->windSum() ? angle : nullptr; |
| } |
| } while (next != firstAngle); |
| if (baseAngle && SK_MinS32 == firstAngle->starter()->windSum()) { |
| firstAngle = baseAngle; |
| tryReverse = true; |
| } |
| if (tryReverse) { |
| baseAngle = nullptr; |
| SkOpAngle* prior = firstAngle; |
| do { |
| angle = prior; |
| prior = angle->previous(); |
| SkASSERT(prior->next() == angle); |
| next = angle->next(); |
| if (prior->unorderable() || angle->unorderable() || next->unorderable()) { |
| baseAngle = nullptr; |
| continue; |
| } |
| int testWinding = angle->starter()->windSum(); |
| if (SK_MinS32 != testWinding) { |
| baseAngle = angle; |
| continue; |
| } |
| if (baseAngle) { |
| ComputeOneSumReverse(baseAngle, angle, includeType); |
| baseAngle = SK_MinS32 != angle->starter()->windSum() ? angle : nullptr; |
| } |
| } while (prior != firstAngle); |
| } |
| return start->starter(end)->windSum(); |
| } |
| |
| void SkOpSegment::release(const SkOpSpan* span) { |
| if (span->done()) { |
| --fDoneCount; |
| } |
| --fCount; |
| SkASSERT(fCount >= fDoneCount); |
| } |
| |
| double SkOpSegment::distSq(double t, const SkOpAngle* oppAngle) const { |
| SkDPoint testPt = this->dPtAtT(t); |
| SkDLine testPerp = {{ testPt, testPt }}; |
| SkDVector slope = this->dSlopeAtT(t); |
| testPerp[1].fX += slope.fY; |
| testPerp[1].fY -= slope.fX; |
| SkIntersections i; |
| const SkOpSegment* oppSegment = oppAngle->segment(); |
| (*CurveIntersectRay[oppSegment->verb()])(oppSegment->pts(), oppSegment->weight(), testPerp, &i); |
| double closestDistSq = SK_ScalarInfinity; |
| for (int index = 0; index < i.used(); ++index) { |
| if (!between(oppAngle->start()->t(), i[0][index], oppAngle->end()->t())) { |
| continue; |
| } |
| double testDistSq = testPt.distanceSquared(i.pt(index)); |
| if (closestDistSq > testDistSq) { |
| closestDistSq = testDistSq; |
| } |
| } |
| return closestDistSq; |
| } |
| |
| void SkOpSegment::findCollapsed() { |
| if (fHead.contains(&fTail)) { |
| markAllDone(); |
| // move start and end to the same point |
| fHead.alignEnd(0, fHead.pt()); |
| fTail.setAligned(); |
| } |
| } |
| |
| /* |
| The M and S variable name parts stand for the operators. |
| Mi stands for Minuend (see wiki subtraction, analogous to difference) |
| Su stands for Subtrahend |
| The Opp variable name part designates that the value is for the Opposite operator. |
| Opposite values result from combining coincident spans. |
| */ |
| SkOpSegment* SkOpSegment::findNextOp(SkTDArray<SkOpSpanBase*>* chase, SkOpSpanBase** nextStart, |
| SkOpSpanBase** nextEnd, bool* unsortable, SkPathOp op, int xorMiMask, int xorSuMask) { |
| SkOpSpanBase* start = *nextStart; |
| SkOpSpanBase* end = *nextEnd; |
| SkASSERT(start != end); |
| int step = start->step(end); |
| SkOpSegment* other = this->isSimple(nextStart, &step); // advances nextStart |
| if (other) { |
| // mark the smaller of startIndex, endIndex done, and all adjacent |
| // spans with the same T value (but not 'other' spans) |
| #if DEBUG_WINDING |
| SkDebugf("%s simple\n", __FUNCTION__); |
| #endif |
| SkOpSpan* startSpan = start->starter(end); |
| if (startSpan->done()) { |
| return nullptr; |
| } |
| markDone(startSpan); |
| *nextEnd = step > 0 ? (*nextStart)->upCast()->next() : (*nextStart)->prev(); |
| return other; |
| } |
| SkOpSpanBase* endNear = step > 0 ? (*nextStart)->upCast()->next() : (*nextStart)->prev(); |
| SkASSERT(endNear == end); // is this ever not end? |
| SkASSERT(endNear); |
| SkASSERT(start != endNear); |
| SkASSERT((start->t() < endNear->t()) ^ (step < 0)); |
| // more than one viable candidate -- measure angles to find best |
| int calcWinding = computeSum(start, endNear, SkOpAngle::kBinaryOpp); |
| bool sortable = calcWinding != SK_NaN32; |
| if (!sortable) { |
| *unsortable = true; |
| markDone(start->starter(end)); |
| return nullptr; |
| } |
| SkOpAngle* angle = this->spanToAngle(end, start); |
| if (angle->unorderable()) { |
| *unsortable = true; |
| markDone(start->starter(end)); |
| return nullptr; |
| } |
| #if DEBUG_SORT |
| SkDebugf("%s\n", __FUNCTION__); |
| angle->debugLoop(); |
| #endif |
| int sumMiWinding = updateWinding(end, start); |
| if (sumMiWinding == SK_MinS32) { |
| *unsortable = true; |
| markDone(start->starter(end)); |
| return nullptr; |
| } |
| int sumSuWinding = updateOppWinding(end, start); |
| if (operand()) { |
| SkTSwap<int>(sumMiWinding, sumSuWinding); |
| } |
| SkOpAngle* nextAngle = angle->next(); |
| const SkOpAngle* foundAngle = nullptr; |
| bool foundDone = false; |
| // iterate through the angle, and compute everyone's winding |
| SkOpSegment* nextSegment; |
| int activeCount = 0; |
| do { |
| nextSegment = nextAngle->segment(); |
| bool activeAngle = nextSegment->activeOp(xorMiMask, xorSuMask, nextAngle->start(), |
| nextAngle->end(), op, &sumMiWinding, &sumSuWinding); |
| if (activeAngle) { |
| ++activeCount; |
| if (!foundAngle || (foundDone && activeCount & 1)) { |
| foundAngle = nextAngle; |
| foundDone = nextSegment->done(nextAngle); |
| } |
| } |
| if (nextSegment->done()) { |
| continue; |
| } |
| if (!activeAngle) { |
| (void) nextSegment->markAndChaseDone(nextAngle->start(), nextAngle->end()); |
| } |
| SkOpSpanBase* last = nextAngle->lastMarked(); |
| if (last) { |
| SkASSERT(!SkPathOpsDebug::ChaseContains(*chase, last)); |
| *chase->append() = last; |
| #if DEBUG_WINDING |
| SkDebugf("%s chase.append segment=%d span=%d", __FUNCTION__, |
| last->segment()->debugID(), last->debugID()); |
| if (!last->final()) { |
| SkDebugf(" windSum=%d", last->upCast()->windSum()); |
| } |
| SkDebugf("\n"); |
| #endif |
| } |
| } while ((nextAngle = nextAngle->next()) != angle); |
| start->segment()->markDone(start->starter(end)); |
| if (!foundAngle) { |
| return nullptr; |
| } |
| *nextStart = foundAngle->start(); |
| *nextEnd = foundAngle->end(); |
| nextSegment = foundAngle->segment(); |
| #if DEBUG_WINDING |
| SkDebugf("%s from:[%d] to:[%d] start=%d end=%d\n", |
| __FUNCTION__, debugID(), nextSegment->debugID(), *nextStart, *nextEnd); |
| #endif |
| return nextSegment; |
| } |
| |
| SkOpSegment* SkOpSegment::findNextWinding(SkTDArray<SkOpSpanBase*>* chase, |
| SkOpSpanBase** nextStart, SkOpSpanBase** nextEnd, bool* unsortable) { |
| SkOpSpanBase* start = *nextStart; |
| SkOpSpanBase* end = *nextEnd; |
| SkASSERT(start != end); |
| int step = start->step(end); |
| SkOpSegment* other = this->isSimple(nextStart, &step); // advances nextStart |
| if (other) { |
| // mark the smaller of startIndex, endIndex done, and all adjacent |
| // spans with the same T value (but not 'other' spans) |
| #if DEBUG_WINDING |
| SkDebugf("%s simple\n", __FUNCTION__); |
| #endif |
| SkOpSpan* startSpan = start->starter(end); |
| if (startSpan->done()) { |
| return nullptr; |
| } |
| markDone(startSpan); |
| *nextEnd = step > 0 ? (*nextStart)->upCast()->next() : (*nextStart)->prev(); |
| return other; |
| } |
| SkOpSpanBase* endNear = step > 0 ? (*nextStart)->upCast()->next() : (*nextStart)->prev(); |
| SkASSERT(endNear == end); // is this ever not end? |
| SkASSERT(endNear); |
| SkASSERT(start != endNear); |
| SkASSERT((start->t() < endNear->t()) ^ (step < 0)); |
| // more than one viable candidate -- measure angles to find best |
| int calcWinding = computeSum(start, endNear, SkOpAngle::kUnaryWinding); |
| bool sortable = calcWinding != SK_NaN32; |
| if (!sortable) { |
| *unsortable = true; |
| markDone(start->starter(end)); |
| return nullptr; |
| } |
| SkOpAngle* angle = this->spanToAngle(end, start); |
| if (angle->unorderable()) { |
| *unsortable = true; |
| markDone(start->starter(end)); |
| return nullptr; |
| } |
| #if DEBUG_SORT |
| SkDebugf("%s\n", __FUNCTION__); |
| angle->debugLoop(); |
| #endif |
| int sumWinding = updateWinding(end, start); |
| SkOpAngle* nextAngle = angle->next(); |
| const SkOpAngle* foundAngle = nullptr; |
| bool foundDone = false; |
| // iterate through the angle, and compute everyone's winding |
| SkOpSegment* nextSegment; |
| int activeCount = 0; |
| do { |
| nextSegment = nextAngle->segment(); |
| bool activeAngle = nextSegment->activeWinding(nextAngle->start(), nextAngle->end(), |
| &sumWinding); |
| if (activeAngle) { |
| ++activeCount; |
| if (!foundAngle || (foundDone && activeCount & 1)) { |
| foundAngle = nextAngle; |
| foundDone = nextSegment->done(nextAngle); |
| } |
| } |
| if (nextSegment->done()) { |
| continue; |
| } |
| if (!activeAngle) { |
| (void) nextSegment->markAndChaseDone(nextAngle->start(), nextAngle->end()); |
| } |
| SkOpSpanBase* last = nextAngle->lastMarked(); |
| if (last) { |
| SkASSERT(!SkPathOpsDebug::ChaseContains(*chase, last)); |
| *chase->append() = last; |
| #if DEBUG_WINDING |
| SkDebugf("%s chase.append segment=%d span=%d", __FUNCTION__, |
| last->segment()->debugID(), last->debugID()); |
| if (!last->final()) { |
| SkDebugf(" windSum=%d", last->upCast()->windSum()); |
| } |
| SkDebugf("\n"); |
| #endif |
| } |
| } while ((nextAngle = nextAngle->next()) != angle); |
| start->segment()->markDone(start->starter(end)); |
| if (!foundAngle) { |
| return nullptr; |
| } |
| *nextStart = foundAngle->start(); |
| *nextEnd = foundAngle->end(); |
| nextSegment = foundAngle->segment(); |
| #if DEBUG_WINDING |
| SkDebugf("%s from:[%d] to:[%d] start=%d end=%d\n", |
| __FUNCTION__, debugID(), nextSegment->debugID(), *nextStart, *nextEnd); |
| #endif |
| return nextSegment; |
| } |
| |
| SkOpSegment* SkOpSegment::findNextXor(SkOpSpanBase** nextStart, SkOpSpanBase** nextEnd, |
| bool* unsortable) { |
| SkOpSpanBase* start = *nextStart; |
| SkOpSpanBase* end = *nextEnd; |
| SkASSERT(start != end); |
| int step = start->step(end); |
| SkOpSegment* other = this->isSimple(nextStart, &step); // advances nextStart |
| if (other) { |
| // mark the smaller of startIndex, endIndex done, and all adjacent |
| // spans with the same T value (but not 'other' spans) |
| #if DEBUG_WINDING |
| SkDebugf("%s simple\n", __FUNCTION__); |
| #endif |
| SkOpSpan* startSpan = start->starter(end); |
| if (startSpan->done()) { |
| return nullptr; |
| } |
| markDone(startSpan); |
| *nextEnd = step > 0 ? (*nextStart)->upCast()->next() : (*nextStart)->prev(); |
| return other; |
| } |
| SkDEBUGCODE(SkOpSpanBase* endNear = step > 0 ? (*nextStart)->upCast()->next() \ |
| : (*nextStart)->prev()); |
| SkASSERT(endNear == end); // is this ever not end? |
| SkASSERT(endNear); |
| SkASSERT(start != endNear); |
| SkASSERT((start->t() < endNear->t()) ^ (step < 0)); |
| SkOpAngle* angle = this->spanToAngle(end, start); |
| if (!angle || angle->unorderable()) { |
| *unsortable = true; |
| markDone(start->starter(end)); |
| return nullptr; |
| } |
| #if DEBUG_SORT |
| SkDebugf("%s\n", __FUNCTION__); |
| angle->debugLoop(); |
| #endif |
| SkOpAngle* nextAngle = angle->next(); |
| const SkOpAngle* foundAngle = nullptr; |
| bool foundDone = false; |
| // iterate through the angle, and compute everyone's winding |
| SkOpSegment* nextSegment; |
| int activeCount = 0; |
| do { |
| nextSegment = nextAngle->segment(); |
| ++activeCount; |
| if (!foundAngle || (foundDone && activeCount & 1)) { |
| foundAngle = nextAngle; |
| if (!(foundDone = nextSegment->done(nextAngle))) { |
| break; |
| } |
| } |
| nextAngle = nextAngle->next(); |
| } while (nextAngle != angle); |
| start->segment()->markDone(start->starter(end)); |
| if (!foundAngle) { |
| return nullptr; |
| } |
| *nextStart = foundAngle->start(); |
| *nextEnd = foundAngle->end(); |
| nextSegment = foundAngle->segment(); |
| #if DEBUG_WINDING |
| SkDebugf("%s from:[%d] to:[%d] start=%d end=%d\n", |
| __FUNCTION__, debugID(), nextSegment->debugID(), *nextStart, *nextEnd); |
| #endif |
| return nextSegment; |
| } |
| |
| SkOpGlobalState* SkOpSegment::globalState() const { |
| return contour()->globalState(); |
| } |
| |
| void SkOpSegment::init(SkPoint pts[], SkScalar weight, SkOpContour* contour, SkPath::Verb verb) { |
| fContour = contour; |
| fNext = nullptr; |
| fOriginal[0] = pts[0]; |
| fOriginal[1] = pts[SkPathOpsVerbToPoints(verb)]; |
| fPts = pts; |
| fWeight = weight; |
| fVerb = verb; |
| fCount = 0; |
| fDoneCount = 0; |
| fVisited = false; |
| SkOpSpan* zeroSpan = &fHead; |
| zeroSpan->init(this, nullptr, 0, fPts[0]); |
| SkOpSpanBase* oneSpan = &fTail; |
| zeroSpan->setNext(oneSpan); |
| oneSpan->initBase(this, zeroSpan, 1, fPts[SkPathOpsVerbToPoints(fVerb)]); |
| SkDEBUGCODE(fID = globalState()->nextSegmentID()); |
| } |
| |
| bool SkOpSegment::isClose(double t, const SkOpSegment* opp) const { |
| SkDPoint cPt = this->dPtAtT(t); |
| SkDVector dxdy = (*CurveDSlopeAtT[this->verb()])(this->pts(), this->weight(), t); |
| SkDLine perp = {{ cPt, {cPt.fX + dxdy.fY, cPt.fY - dxdy.fX} }}; |
| SkIntersections i; |
| (*CurveIntersectRay[opp->verb()])(opp->pts(), opp->weight(), perp, &i); |
| int used = i.used(); |
| for (int index = 0; index < used; ++index) { |
| if (cPt.roughlyEqual(i.pt(index))) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| bool SkOpSegment::isXor() const { |
| return fContour->isXor(); |
| } |
| |
| void SkOpSegment::markAllDone() { |
| SkOpSpan* span = this->head(); |
| do { |
| this->markDone(span); |
| } while ((span = span->next()->upCastable())); |
| } |
| |
| SkOpSpanBase* SkOpSegment::markAndChaseDone(SkOpSpanBase* start, SkOpSpanBase* end) { |
| int step = start->step(end); |
| SkOpSpan* minSpan = start->starter(end); |
| markDone(minSpan); |
| SkOpSpanBase* last = nullptr; |
| SkOpSegment* other = this; |
| while ((other = other->nextChase(&start, &step, &minSpan, &last))) { |
| if (other->done()) { |
| SkASSERT(!last); |
| break; |
| } |
| other->markDone(minSpan); |
| } |
| return last; |
| } |
| |
| bool SkOpSegment::markAndChaseWinding(SkOpSpanBase* start, SkOpSpanBase* end, int winding, |
| SkOpSpanBase** lastPtr) { |
| SkOpSpan* spanStart = start->starter(end); |
| int step = start->step(end); |
| bool success = markWinding(spanStart, winding); |
| SkOpSpanBase* last = nullptr; |
| SkOpSegment* other = this; |
| while ((other = other->nextChase(&start, &step, &spanStart, &last))) { |
| if (spanStart->windSum() != SK_MinS32) { |
| SkASSERT(spanStart->windSum() == winding); |
| SkASSERT(!last); |
| break; |
| } |
| (void) other->markWinding(spanStart, winding); |
| } |
| if (lastPtr) { |
| *lastPtr = last; |
| } |
| return success; |
| } |
| |
| bool SkOpSegment::markAndChaseWinding(SkOpSpanBase* start, SkOpSpanBase* end, |
| int winding, int oppWinding, SkOpSpanBase** lastPtr) { |
| SkOpSpan* spanStart = start->starter(end); |
| int step = start->step(end); |
| bool success = markWinding(spanStart, winding, oppWinding); |
| SkOpSpanBase* last = nullptr; |
| SkOpSegment* other = this; |
| while ((other = other->nextChase(&start, &step, &spanStart, &last))) { |
| if (spanStart->windSum() != SK_MinS32) { |
| if (this->operand() == other->operand()) { |
| if (spanStart->windSum() != winding || spanStart->oppSum() != oppWinding) { |
| this->globalState()->setWindingFailed(); |
| return false; |
| } |
| } else { |
| SkASSERT(spanStart->windSum() == oppWinding); |
| SkASSERT(spanStart->oppSum() == winding); |
| } |
| SkASSERT(!last); |
| break; |
| } |
| if (this->operand() == other->operand()) { |
| (void) other->markWinding(spanStart, winding, oppWinding); |
| } else { |
| (void) other->markWinding(spanStart, oppWinding, winding); |
| } |
| } |
| if (lastPtr) { |
| *lastPtr = last; |
| } |
| return success; |
| } |
| |
| SkOpSpanBase* SkOpSegment::markAngle(int maxWinding, int sumWinding, const SkOpAngle* angle) { |
| SkASSERT(angle->segment() == this); |
| if (UseInnerWinding(maxWinding, sumWinding)) { |
| maxWinding = sumWinding; |
| } |
| SkOpSpanBase* last; |
| (void) markAndChaseWinding(angle->start(), angle->end(), maxWinding, &last); |
| #if DEBUG_WINDING |
| if (last) { |
| SkDebugf("%s last seg=%d span=%d", __FUNCTION__, |
| last->segment()->debugID(), last->debugID()); |
| if (!last->final()) { |
| SkDebugf(" windSum="); |
| SkPathOpsDebug::WindingPrintf(last->upCast()->windSum()); |
| } |
| SkDebugf("\n"); |
| } |
| #endif |
| return last; |
| } |
| |
| SkOpSpanBase* SkOpSegment::markAngle(int maxWinding, int sumWinding, int oppMaxWinding, |
| int oppSumWinding, const SkOpAngle* angle) { |
| SkASSERT(angle->segment() == this); |
| if (UseInnerWinding(maxWinding, sumWinding)) { |
| maxWinding = sumWinding; |
| } |
| if (oppMaxWinding != oppSumWinding && UseInnerWinding(oppMaxWinding, oppSumWinding)) { |
| oppMaxWinding = oppSumWinding; |
| } |
| SkOpSpanBase* last = nullptr; |
| // caller doesn't require that this marks anything |
| (void) markAndChaseWinding(angle->start(), angle->end(), maxWinding, oppMaxWinding, &last); |
| #if DEBUG_WINDING |
| if (last) { |
| SkDebugf("%s last segment=%d span=%d", __FUNCTION__, |
| last->segment()->debugID(), last->debugID()); |
| if (!last->final()) { |
| SkDebugf(" windSum="); |
| SkPathOpsDebug::WindingPrintf(last->upCast()->windSum()); |
| } |
| SkDebugf(" \n"); |
| } |
| #endif |
| return last; |
| } |
| |
| void SkOpSegment::markDone(SkOpSpan* span) { |
| SkASSERT(this == span->segment()); |
| if (span->done()) { |
| return; |
| } |
| #if DEBUG_MARK_DONE |
| debugShowNewWinding(__FUNCTION__, span, span->windSum(), span->oppSum()); |
| #endif |
| span->setDone(true); |
| ++fDoneCount; |
| debugValidate(); |
| } |
| |
| bool SkOpSegment::markWinding(SkOpSpan* span, int winding) { |
| SkASSERT(this == span->segment()); |
| SkASSERT(winding); |
| if (span->done()) { |
| return false; |
| } |
| #if DEBUG_MARK_DONE |
| debugShowNewWinding(__FUNCTION__, span, winding); |
| #endif |
| span->setWindSum(winding); |
| debugValidate(); |
| return true; |
| } |
| |
| bool SkOpSegment::markWinding(SkOpSpan* span, int winding, int oppWinding) { |
| SkASSERT(this == span->segment()); |
| SkASSERT(winding || oppWinding); |
| if (span->done()) { |
| return false; |
| } |
| #if DEBUG_MARK_DONE |
| debugShowNewWinding(__FUNCTION__, span, winding, oppWinding); |
| #endif |
| span->setWindSum(winding); |
| span->setOppSum(oppWinding); |
| debugValidate(); |
| return true; |
| } |
| |
| bool SkOpSegment::match(const SkOpPtT* base, const SkOpSegment* testParent, double testT, |
| const SkPoint& testPt) const { |
| const SkOpSegment* baseParent = base->segment(); |
| if (this == baseParent && this == testParent && precisely_equal(base->fT, testT)) { |
| return true; |
| } |
| if (!SkDPoint::ApproximatelyEqual(testPt, base->fPt)) { |
| return false; |
| } |
| return !this->ptsDisjoint(base->fT, base->fPt, testT, testPt); |
| } |
| |
| static SkOpSegment* set_last(SkOpSpanBase** last, SkOpSpanBase* endSpan) { |
| if (last) { |
| *last = endSpan; |
| } |
| return nullptr; |
| } |
| |
| SkOpSegment* SkOpSegment::nextChase(SkOpSpanBase** startPtr, int* stepPtr, SkOpSpan** minPtr, |
| SkOpSpanBase** last) const { |
| SkOpSpanBase* origStart = *startPtr; |
| int step = *stepPtr; |
| SkOpSpanBase* endSpan = step > 0 ? origStart->upCast()->next() : origStart->prev(); |
| SkASSERT(endSpan); |
| SkOpAngle* angle = step > 0 ? endSpan->fromAngle() : endSpan->upCast()->toAngle(); |
| SkOpSpanBase* foundSpan; |
| SkOpSpanBase* otherEnd; |
| SkOpSegment* other; |
| if (angle == nullptr) { |
| if (endSpan->t() != 0 && endSpan->t() != 1) { |
| return nullptr; |
| } |
| SkOpPtT* otherPtT = endSpan->ptT()->next(); |
| other = otherPtT->segment(); |
| foundSpan = otherPtT->span(); |
| otherEnd = step > 0 |
| ? foundSpan->upCastable() ? foundSpan->upCast()->next() : nullptr |
| : foundSpan->prev(); |
| } else { |
| int loopCount = angle->loopCount(); |
| if (loopCount > 2) { |
| return set_last(last, endSpan); |
| } |
| const SkOpAngle* next = angle->next(); |
| if (nullptr == next) { |
| return nullptr; |
| } |
| #if DEBUG_WINDING |
| if (angle->debugSign() != next->debugSign() && !angle->segment()->contour()->isXor() |
| && !next->segment()->contour()->isXor()) { |
| SkDebugf("%s mismatched signs\n", __FUNCTION__); |
| } |
| #endif |
| other = next->segment(); |
| foundSpan = endSpan = next->start(); |
| otherEnd = next->end(); |
| } |
| if (!otherEnd) { |
| return nullptr; |
| } |
| int foundStep = foundSpan->step(otherEnd); |
| if (*stepPtr != foundStep) { |
| return set_last(last, endSpan); |
| } |
| SkASSERT(*startPtr); |
| if (!otherEnd) { |
| return nullptr; |
| } |
| // SkASSERT(otherEnd >= 0); |
| SkOpSpan* origMin = step < 0 ? origStart->prev() : origStart->upCast(); |
| SkOpSpan* foundMin = foundSpan->starter(otherEnd); |
| if (foundMin->windValue() != origMin->windValue() |
| || foundMin->oppValue() != origMin->oppValue()) { |
| return set_last(last, endSpan); |
| } |
| *startPtr = foundSpan; |
| *stepPtr = foundStep; |
| if (minPtr) { |
| *minPtr = foundMin; |
| } |
| return other; |
| } |
| |
| static void clear_visited(SkOpSpanBase* span) { |
| // reset visited flag back to false |
| do { |
| SkOpPtT* ptT = span->ptT(), * stopPtT = ptT; |
| while ((ptT = ptT->next()) != stopPtT) { |
| SkOpSegment* opp = ptT->segment(); |
| opp->resetVisited(); |
| } |
| } while (!span->final() && (span = span->upCast()->next())); |
| } |
| |
| // look for pairs of undetected coincident curves |
| // assumes that segments going in have visited flag clear |
| // curve/curve intersection should now do a pretty good job of finding coincident runs so |
| // this may be only be necessary for line/curve pairs -- so skip unless this is a line and the |
| // the opp is not a line |
| bool SkOpSegment::missingCoincidence(SkOpCoincidence* coincidences, SkChunkAlloc* allocator) { |
| if (this->verb() != SkPath::kLine_Verb) { |
| return false; |
| } |
| if (this->done()) { |
| return false; |
| } |
| SkOpSpan* prior = nullptr; |
| SkOpSpanBase* spanBase = &fHead; |
| do { |
| SkOpPtT* ptT = spanBase->ptT(), * spanStopPtT = ptT; |
| SkASSERT(ptT->span() == spanBase); |
| while ((ptT = ptT->next()) != spanStopPtT) { |
| if (ptT->deleted()) { |
| continue; |
| } |
| SkOpSegment* opp = ptT->span()->segment(); |
| // if (opp->verb() == SkPath::kLine_Verb) { |
| // continue; |
| // } |
| if (opp->done()) { |
| continue; |
| } |
| // when opp is encounted the 1st time, continue; on 2nd encounter, look for coincidence |
| if (!opp->visited()) { |
| continue; |
| } |
| if (spanBase == &fHead) { |
| continue; |
| } |
| SkOpSpan* span = spanBase->upCastable(); |
| // FIXME?: this assumes that if the opposite segment is coincident then no more |
| // coincidence needs to be detected. This may not be true. |
| if (span && span->containsCoincidence(opp)) { |
| continue; |
| } |
| if (spanBase->segment() == opp) { |
| continue; |
| } |
| if (spanBase->containsCoinEnd(opp)) { |
| continue; |
| } |
| SkOpPtT* priorPtT = nullptr, * priorStopPtT; |
| // find prior span containing opp segment |
| SkOpSegment* priorOpp = nullptr; |
| SkOpSpan* priorTest = spanBase->prev(); |
| while (!priorOpp && priorTest) { |
| priorStopPtT = priorPtT = priorTest->ptT(); |
| while ((priorPtT = priorPtT->next()) != priorStopPtT) { |
| if (priorPtT->deleted()) { |
| continue; |
| } |
| SkOpSegment* segment = priorPtT->span()->segment(); |
| if (segment == opp) { |
| prior = priorTest; |
| priorOpp = opp; |
| break; |
| } |
| } |
| priorTest = priorTest->prev(); |
| } |
| if (!priorOpp) { |
| continue; |
| } |
| if (priorPtT == ptT) { |
| continue; |
| } |
| SkOpPtT* oppStart = prior->ptT(); |
| SkOpPtT* oppEnd = spanBase->ptT(); |
| bool swapped = priorPtT->fT > ptT->fT; |
| if (swapped) { |
| SkTSwap(priorPtT, ptT); |
| SkTSwap(oppStart, oppEnd); |
| } |
| bool flipped = oppStart->fT > oppEnd->fT; |
| bool coincident = false; |
| if (coincidences->contains(priorPtT, ptT, oppStart, oppEnd, flipped)) { |
| goto swapBack; |
| } |
| if (opp->verb() == SkPath::kLine_Verb) { |
| coincident = (SkDPoint::ApproximatelyEqual(priorPtT->fPt, oppStart->fPt) || |
| SkDPoint::ApproximatelyEqual(priorPtT->fPt, oppEnd->fPt)) && |
| (SkDPoint::ApproximatelyEqual(ptT->fPt, oppStart->fPt) || |
| SkDPoint::ApproximatelyEqual(ptT->fPt, oppEnd->fPt)); |
| } |
| if (!coincident) { |
| coincident = testForCoincidence(priorPtT, ptT, prior, spanBase, opp, 5000); |
| } |
| if (coincident) { |
| // mark coincidence |
| if (!coincidences->extend(priorPtT, ptT, oppStart, oppEnd) |
| && !coincidences->extend(oppStart, oppEnd, priorPtT, ptT)) { |
| coincidences->add(priorPtT, ptT, oppStart, oppEnd, allocator); |
| } |
| clear_visited(&fHead); |
| return true; |
| } |
| swapBack: |
| if (swapped) { |
| SkTSwap(priorPtT, ptT); |
| } |
| } |
| } while ((spanBase = spanBase->final() ? nullptr : spanBase->upCast()->next())); |
| clear_visited(&fHead); |
| return false; |
| } |
| |
| // if a span has more than one intersection, merge the other segments' span as needed |
| bool SkOpSegment::moveMultiples() { |
| debugValidate(); |
| SkOpSpanBase* test = &fHead; |
| do { |
| int addCount = test->spanAddsCount(); |
| if (addCount < 1) { |
| return false; |
| } |
| if (addCount == 1) { |
| continue; |
| } |
| SkOpPtT* startPtT = test->ptT(); |
| SkOpPtT* testPtT = startPtT; |
| do { // iterate through all spans associated with start |
| SkOpSpanBase* oppSpan = testPtT->span(); |
| if (oppSpan->spanAddsCount() == addCount) { |
| continue; |
| } |
| if (oppSpan->deleted()) { |
| continue; |
| } |
| SkOpSegment* oppSegment = oppSpan->segment(); |
| if (oppSegment == this) { |
| continue; |
| } |
| // find range of spans to consider merging |
| SkOpSpanBase* oppPrev = oppSpan; |
| SkOpSpanBase* oppFirst = oppSpan; |
| while ((oppPrev = oppPrev->prev())) { |
| if (!roughly_equal(oppPrev->t(), oppSpan->t())) { |
| break; |
| } |
| if (oppPrev->spanAddsCount() == addCount) { |
| continue; |
| } |
| if (oppPrev->deleted()) { |
| continue; |
| } |
| oppFirst = oppPrev; |
| } |
| SkOpSpanBase* oppNext = oppSpan; |
| SkOpSpanBase* oppLast = oppSpan; |
| while ((oppNext = oppNext->final() ? nullptr : oppNext->upCast()->next())) { |
| if (!roughly_equal(oppNext->t(), oppSpan->t())) { |
| break; |
| } |
| if (oppNext->spanAddsCount() == addCount) { |
| continue; |
| } |
| if (oppNext->deleted()) { |
| continue; |
| } |
| oppLast = oppNext; |
| } |
| if (oppFirst == oppLast) { |
| continue; |
| } |
| SkOpSpanBase* oppTest = oppFirst; |
| do { |
| if (oppTest == oppSpan) { |
| continue; |
| } |
| // check to see if the candidate meets specific criteria: |
| // it contains spans of segments in test's loop but not including 'this' |
| SkOpPtT* oppStartPtT = oppTest->ptT(); |
| SkOpPtT* oppPtT = oppStartPtT; |
| while ((oppPtT = oppPtT->next()) != oppStartPtT) { |
| SkOpSegment* oppPtTSegment = oppPtT->segment(); |
| if (oppPtTSegment == this) { |
| goto tryNextSpan; |
| } |
| SkOpPtT* matchPtT = startPtT; |
| do { |
| if (matchPtT->segment() == oppPtTSegment) { |
| goto foundMatch; |
| } |
| } while ((matchPtT = matchPtT->next()) != startPtT); |
| goto tryNextSpan; |
| foundMatch: // merge oppTest and oppSpan |
| oppSegment->debugValidate(); |
| if (oppTest == &oppSegment->fTail || oppTest == &oppSegment->fHead) { |
| SkASSERT(oppSpan != &oppSegment->fHead); // don't expect collapse |
| SkASSERT(oppSpan != &oppSegment->fTail); |
| oppTest->merge(oppSpan->upCast()); |
| } else { |
| oppSpan->merge(oppTest->upCast()); |
| } |
| oppSegment->debugValidate(); |
| goto checkNextSpan; |
| } |
| tryNextSpan: |
| ; |
| } while (oppTest != oppLast && (oppTest = oppTest->upCast()->next())); |
| } while ((testPtT = testPtT->next()) != startPtT); |
| checkNextSpan: |
| ; |
| } while ((test = test->final() ? nullptr : test->upCast()->next())); |
| debugValidate(); |
| return true; |
| } |
| |
| // Move nearby t values and pts so they all hang off the same span. Alignment happens later. |
| void SkOpSegment::moveNearby() { |
| debugValidate(); |
| SkOpSpanBase* spanS = &fHead; |
| do { |
| SkOpSpanBase* test = spanS->upCast()->next(); |
| SkOpSpanBase* next; |
| if (spanS->contains(test)) { |
| if (!test->final()) { |
| test->upCast()->release(spanS->ptT()); |
| continue; |
| } else if (spanS != &fHead) { |
| spanS->upCast()->release(test->ptT()); |
| spanS = test; |
| continue; |
| } |
| } |
| do { // iterate through all spans associated with start |
| SkOpPtT* startBase = spanS->ptT(); |
| next = test->final() ? nullptr : test->upCast()->next(); |
| do { |
| SkOpPtT* testBase = test->ptT(); |
| do { |
| if (startBase == testBase) { |
| goto checkNextSpan; |
| } |
| if (testBase->duplicate()) { |
| continue; |
| } |
| if (this->match(startBase, testBase->segment(), testBase->fT, testBase->fPt)) { |
| if (test == &this->fTail) { |
| if (spanS == &fHead) { |
| debugValidate(); |
| return; // if this span has collapsed, remove it from parent |
| } |
| this->fTail.merge(spanS->upCast()); |
| debugValidate(); |
| return; |
| } |
| spanS->merge(test->upCast()); |
| goto checkNextSpan; |
| } |
| } while ((testBase = testBase->next()) != test->ptT()); |
| } while ((startBase = startBase->next()) != spanS->ptT()); |
| checkNextSpan: |
| ; |
| } while ((test = next)); |
| spanS = spanS->upCast()->next(); |
| } while (!spanS->final()); |
| debugValidate(); |
| } |
| |
| bool SkOpSegment::operand() const { |
| return fContour->operand(); |
| } |
| |
| bool SkOpSegment::oppXor() const { |
| return fContour->oppXor(); |
| } |
| |
| bool SkOpSegment::ptsDisjoint(double t1, const SkPoint& pt1, double t2, const SkPoint& pt2) const { |
| if (fVerb == SkPath::kLine_Verb) { |
| return false; |
| } |
| // quads (and cubics) can loop back to nearly a line so that an opposite curve |
| // hits in two places with very different t values. |
| // OPTIMIZATION: curves could be preflighted so that, for example, something like |
| // 'controls contained by ends' could avoid this check for common curves |
| // 'ends are extremes in x or y' is cheaper to compute and real-world common |
| // on the other hand, the below check is relatively inexpensive |
| double midT = (t1 + t2) / 2; |
| SkPoint midPt = this->ptAtT(midT); |
| double seDistSq = SkTMax(pt1.distanceToSqd(pt2) * 2, FLT_EPSILON * 2); |
| return midPt.distanceToSqd(pt1) > seDistSq || midPt.distanceToSqd(pt2) > seDistSq; |
| } |
| |
| void SkOpSegment::setUpWindings(SkOpSpanBase* start, SkOpSpanBase* end, int* sumMiWinding, |
| int* maxWinding, int* sumWinding) { |
| int deltaSum = SpanSign(start, end); |
| *maxWinding = *sumMiWinding; |
| *sumWinding = *sumMiWinding -= deltaSum; |
| SkASSERT(!DEBUG_LIMIT_WIND_SUM || SkTAbs(*sumWinding) <= DEBUG_LIMIT_WIND_SUM); |
| } |
| |
| void SkOpSegment::setUpWindings(SkOpSpanBase* start, SkOpSpanBase* end, int* sumMiWinding, |
| int* sumSuWinding, int* maxWinding, int* sumWinding, int* oppMaxWinding, |
| int* oppSumWinding) { |
| int deltaSum = SpanSign(start, end); |
| int oppDeltaSum = OppSign(start, end); |
| if (operand()) { |
| *maxWinding = *sumSuWinding; |
| *sumWinding = *sumSuWinding -= deltaSum; |
| *oppMaxWinding = *sumMiWinding; |
| *oppSumWinding = *sumMiWinding -= oppDeltaSum; |
| } else { |
| *maxWinding = *sumMiWinding; |
| *sumWinding = *sumMiWinding -= deltaSum; |
| *oppMaxWinding = *sumSuWinding; |
| *oppSumWinding = *sumSuWinding -= oppDeltaSum; |
| } |
| SkASSERT(!DEBUG_LIMIT_WIND_SUM || SkTAbs(*sumWinding) <= DEBUG_LIMIT_WIND_SUM); |
| SkASSERT(!DEBUG_LIMIT_WIND_SUM || SkTAbs(*oppSumWinding) <= DEBUG_LIMIT_WIND_SUM); |
| } |
| |
| void SkOpSegment::sortAngles() { |
| SkOpSpanBase* span = &this->fHead; |
| do { |
| SkOpAngle* fromAngle = span->fromAngle(); |
| SkOpAngle* toAngle = span->final() ? nullptr : span->upCast()->toAngle(); |
| if (!fromAngle && !toAngle) { |
| continue; |
| } |
| #if DEBUG_ANGLE |
| bool wroteAfterHeader = false; |
| #endif |
| SkOpAngle* baseAngle = fromAngle; |
| if (fromAngle && toAngle) { |
| #if DEBUG_ANGLE |
| SkDebugf("%s [%d] tStart=%1.9g [%d]\n", __FUNCTION__, debugID(), span->t(), |
| span->debugID()); |
| wroteAfterHeader = true; |
| #endif |
| fromAngle->insert(toAngle); |
| } else if (!fromAngle) { |
| baseAngle = toAngle; |
| } |
| SkOpPtT* ptT = span->ptT(), * stopPtT = ptT; |
| do { |
| SkOpSpanBase* oSpan = ptT->span(); |
| if (oSpan == span) { |
| continue; |
| } |
| SkOpAngle* oAngle = oSpan->fromAngle(); |
| if (oAngle) { |
| #if DEBUG_ANGLE |
| if (!wroteAfterHeader) { |
| SkDebugf("%s [%d] tStart=%1.9g [%d]\n", __FUNCTION__, debugID(), |
| span->t(), span->debugID()); |
| wroteAfterHeader = true; |
| } |
| #endif |
| if (!oAngle->loopContains(baseAngle)) { |
| baseAngle->insert(oAngle); |
| } |
| } |
| if (!oSpan->final()) { |
| oAngle = oSpan->upCast()->toAngle(); |
| if (oAngle) { |
| #if DEBUG_ANGLE |
| if (!wroteAfterHeader) { |
| SkDebugf("%s [%d] tStart=%1.9g [%d]\n", __FUNCTION__, debugID(), |
| span->t(), span->debugID()); |
| wroteAfterHeader = true; |
| } |
| #endif |
| if (!oAngle->loopContains(baseAngle)) { |
| baseAngle->insert(oAngle); |
| } |
| } |
| } |
| } while ((ptT = ptT->next()) != stopPtT); |
| if (baseAngle->loopCount() == 1) { |
| span->setFromAngle(nullptr); |
| if (toAngle) { |
| span->upCast()->setToAngle(nullptr); |
| } |
| baseAngle = nullptr; |
| } |
| #if DEBUG_SORT |
| SkASSERT(!baseAngle || baseAngle->loopCount() > 1); |
| #endif |
| } while (!span->final() && (span = span->upCast()->next())); |
| } |
| |
| // return true if midpoints were computed |
| bool SkOpSegment::subDivide(const SkOpSpanBase* start, const SkOpSpanBase* end, |
| SkOpCurve* edge) const { |
| SkASSERT(start != end); |
| const SkOpPtT& startPtT = *start->ptT(); |
| const SkOpPtT& endPtT = *end->ptT(); |
| SkDEBUGCODE(edge->fVerb = fVerb); |
| edge->fPts[0] = startPtT.fPt; |
| int points = SkPathOpsVerbToPoints(fVerb); |
| edge->fPts[points] = endPtT.fPt; |
| edge->fWeight = 1; |
| if (fVerb == SkPath::kLine_Verb) { |
| return false; |
| } |
| double startT = startPtT.fT; |
| double endT = endPtT.fT; |
| if ((startT == 0 || endT == 0) && (startT == 1 || endT == 1)) { |
| // don't compute midpoints if we already have them |
| if (fVerb == SkPath::kQuad_Verb) { |
| edge->fPts[1] = fPts[1]; |
| return false; |
| } |
| if (fVerb == SkPath::kConic_Verb) { |
| edge->fPts[1] = fPts[1]; |
| edge->fWeight = fWeight; |
| return false; |
| } |
| SkASSERT(fVerb == SkPath::kCubic_Verb); |
| if (start < end) { |
| edge->fPts[1] = fPts[1]; |
| edge->fPts[2] = fPts[2]; |
| return false; |
| } |
| edge->fPts[1] = fPts[2]; |
| edge->fPts[2] = fPts[1]; |
| return false; |
| } |
| const SkDPoint sub[2] = {{ edge->fPts[0].fX, edge->fPts[0].fY}, |
| {edge->fPts[points].fX, edge->fPts[points].fY }}; |
| if (fVerb == SkPath::kQuad_Verb) { |
| edge->fPts[1] = SkDQuad::SubDivide(fPts, sub[0], sub[1], startT, endT).asSkPoint(); |
| } else if (fVerb == SkPath::kConic_Verb) { |
| edge->fPts[1] = SkDConic::SubDivide(fPts, fWeight, sub[0], sub[1], |
| startT, endT, &edge->fWeight).asSkPoint(); |
| } else { |
| SkASSERT(fVerb == SkPath::kCubic_Verb); |
| SkDPoint ctrl[2]; |
| SkDCubic::SubDivide(fPts, sub[0], sub[1], startT, endT, ctrl); |
| edge->fPts[1] = ctrl[0].asSkPoint(); |
| edge->fPts[2] = ctrl[1].asSkPoint(); |
| } |
| return true; |
| } |
| |
| bool SkOpSegment::subDivide(const SkOpSpanBase* start, const SkOpSpanBase* end, |
| SkDCurve* edge) const { |
| SkASSERT(start != end); |
| const SkOpPtT& startPtT = *start->ptT(); |
| const SkOpPtT& endPtT = *end->ptT(); |
| SkDEBUGCODE(edge->fVerb = fVerb); |
| edge->fCubic[0].set(startPtT.fPt); |
| int points = SkPathOpsVerbToPoints(fVerb); |
| edge->fCubic[points].set(endPtT.fPt); |
| if (fVerb == SkPath::kLine_Verb) { |
| return false; |
| } |
| double startT = startPtT.fT; |
| double endT = endPtT.fT; |
| if ((startT == 0 || endT == 0) && (startT == 1 || endT == 1)) { |
| // don't compute midpoints if we already have them |
| if (fVerb == SkPath::kQuad_Verb) { |
| edge->fLine[1].set(fPts[1]); |
| return false; |
| } |
| if (fVerb == SkPath::kConic_Verb) { |
| edge->fConic[1].set(fPts[1]); |
| edge->fConic.fWeight = fWeight; |
| return false; |
| } |
| SkASSERT(fVerb == SkPath::kCubic_Verb); |
| if (startT == 0) { |
| edge->fCubic[1].set(fPts[1]); |
| edge->fCubic[2].set(fPts[2]); |
| return false; |
| } |
| edge->fCubic[1].set(fPts[2]); |
| edge->fCubic[2].set(fPts[1]); |
| return false; |
| } |
| if (fVerb == SkPath::kQuad_Verb) { |
| edge->fQuad[1] = SkDQuad::SubDivide(fPts, edge->fQuad[0], edge->fQuad[2], startT, endT); |
| } else if (fVerb == SkPath::kConic_Verb) { |
| edge->fConic[1] = SkDConic::SubDivide(fPts, fWeight, edge->fQuad[0], edge->fQuad[2], |
| startT, endT, &edge->fConic.fWeight); |
| } else { |
| SkASSERT(fVerb == SkPath::kCubic_Verb); |
| SkDCubic::SubDivide(fPts, edge->fCubic[0], edge->fCubic[3], startT, endT, &edge->fCubic[1]); |
| } |
| return true; |
| } |
| |
| bool SkOpSegment::testForCoincidence(const SkOpPtT* priorPtT, const SkOpPtT* ptT, |
| const SkOpSpanBase* prior, const SkOpSpanBase* spanBase, const SkOpSegment* opp, |
| SkScalar flatnessLimit) const { |
| // average t, find mid pt |
| double midT = (prior->t() + spanBase->t()) / 2; |
| SkPoint midPt = this->ptAtT(midT); |
| bool coincident = true; |
| // if the mid pt is not near either end pt, project perpendicular through opp seg |
| if (!SkDPoint::ApproximatelyEqual(priorPtT->fPt, midPt) |
| && !SkDPoint::ApproximatelyEqual(ptT->fPt, midPt)) { |
| coincident = false; |
| SkIntersections i; |
| SkVector dxdy = (*CurveSlopeAtT[fVerb])(this->pts(), this->weight(), midT); |
| SkDLine ray = {{{midPt.fX, midPt.fY}, |
| {(double) midPt.fX + dxdy.fY, (double) midPt.fY - dxdy.fX}}}; |
| (*CurveIntersectRay[opp->verb()])(opp->pts(), opp->weight(), ray, &i); |
| // measure distance and see if it's small enough to denote coincidence |
| for (int index = 0; index < i.used(); ++index) { |
| SkDPoint oppPt = i.pt(index); |
| if (oppPt.approximatelyEqual(midPt)) { |
| SkVector oppDxdy = (*CurveSlopeAtT[opp->verb()])(opp->pts(), |
| opp->weight(), i[index][0]); |
| oppDxdy.normalize(); |
| dxdy.normalize(); |
| SkScalar flatness = SkScalarAbs(dxdy.cross(oppDxdy) / FLT_EPSILON); |
| coincident |= flatness < flatnessLimit; |
| } |
| } |
| } |
| return coincident; |
| } |
| |
| void SkOpSegment::undoneSpan(SkOpSpanBase** start, SkOpSpanBase** end) { |
| SkOpSpan* span = this->head(); |
| do { |
| if (!span->done()) { |
| break; |
| } |
| } while ((span = span->next()->upCastable())); |
| SkASSERT(span); |
| *start = span; |
| *end = span->next(); |
| } |
| |
| int SkOpSegment::updateOppWinding(const SkOpSpanBase* start, const SkOpSpanBase* end) const { |
| const SkOpSpan* lesser = start->starter(end); |
| int oppWinding = lesser->oppSum(); |
| int oppSpanWinding = SkOpSegment::OppSign(start, end); |
| if (oppSpanWinding && UseInnerWinding(oppWinding - oppSpanWinding, oppWinding) |
| && oppWinding != SK_MaxS32) { |
| oppWinding -= oppSpanWinding; |
| } |
| return oppWinding; |
| } |
| |
| int SkOpSegment::updateOppWinding(const SkOpAngle* angle) const { |
| const SkOpSpanBase* startSpan = angle->start(); |
| const SkOpSpanBase* endSpan = angle->end(); |
| return updateOppWinding(endSpan, startSpan); |
| } |
| |
| int SkOpSegment::updateOppWindingReverse(const SkOpAngle* angle) const { |
| const SkOpSpanBase* startSpan = angle->start(); |
| const SkOpSpanBase* endSpan = angle->end(); |
| return updateOppWinding(startSpan, endSpan); |
| } |
| |
| int SkOpSegment::updateWinding(SkOpSpanBase* start, SkOpSpanBase* end) { |
| SkOpSpan* lesser = start->starter(end); |
| int winding = lesser->windSum(); |
| if (winding == SK_MinS32) { |
| winding = lesser->computeWindSum(); |
| } |
| if (winding == SK_MinS32) { |
| return winding; |
| } |
| int spanWinding = SkOpSegment::SpanSign(start, end); |
| if (winding && UseInnerWinding(winding - spanWinding, winding) |
| && winding != SK_MaxS32) { |
| winding -= spanWinding; |
| } |
| return winding; |
| } |
| |
| int SkOpSegment::updateWinding(SkOpAngle* angle) { |
| SkOpSpanBase* startSpan = angle->start(); |
| SkOpSpanBase* endSpan = angle->end(); |
| return updateWinding(endSpan, startSpan); |
| } |
| |
| int SkOpSegment::updateWindingReverse(const SkOpAngle* angle) { |
| SkOpSpanBase* startSpan = angle->start(); |
| SkOpSpanBase* endSpan = angle->end(); |
| return updateWinding(startSpan, endSpan); |
| } |
| |
| // OPTIMIZATION: does the following also work, and is it any faster? |
| // return outerWinding * innerWinding > 0 |
| // || ((outerWinding + innerWinding < 0) ^ ((outerWinding - innerWinding) < 0))) |
| bool SkOpSegment::UseInnerWinding(int outerWinding, int innerWinding) { |
| SkASSERT(outerWinding != SK_MaxS32); |
| SkASSERT(innerWinding != SK_MaxS32); |
| int absOut = SkTAbs(outerWinding); |
| int absIn = SkTAbs(innerWinding); |
| bool result = absOut == absIn ? outerWinding < 0 : absOut < absIn; |
| return result; |
| } |
| |
| int SkOpSegment::windSum(const SkOpAngle* angle) const { |
| const SkOpSpan* minSpan = angle->start()->starter(angle->end()); |
| return minSpan->windSum(); |
| } |
