| /* |
| * 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 "SkAddIntersections.h" |
| #include "SkOpEdgeBuilder.h" |
| #include "SkPathOpsCommon.h" |
| #include "SkPathWriter.h" |
| |
| static bool bridgeWinding(SkTDArray<SkOpContour*>& contourList, SkPathWriter* simple) { |
| bool firstContour = true; |
| bool unsortable = false; |
| bool topUnsortable = false; |
| SkPoint topLeft = {SK_ScalarMin, SK_ScalarMin}; |
| do { |
| int index, endIndex; |
| bool topDone; |
| SkOpSegment* current = FindSortableTop(contourList, &firstContour, &index, &endIndex, |
| &topLeft, &topUnsortable, &topDone, false); |
| if (!current) { |
| if (topUnsortable || !topDone) { |
| topUnsortable = false; |
| SkASSERT(topLeft.fX != SK_ScalarMin && topLeft.fY != SK_ScalarMin); |
| topLeft.fX = topLeft.fY = SK_ScalarMin; |
| continue; |
| } |
| break; |
| } |
| SkTDArray<SkOpSpan*> chaseArray; |
| do { |
| if (current->activeWinding(index, endIndex)) { |
| do { |
| if (!unsortable && current->done()) { |
| #if DEBUG_ACTIVE_SPANS |
| DebugShowActiveSpans(contourList); |
| #endif |
| if (simple->isEmpty()) { |
| simple->init(); |
| break; |
| } |
| } |
| SkASSERT(unsortable || !current->done()); |
| int nextStart = index; |
| int nextEnd = endIndex; |
| SkOpSegment* next = current->findNextWinding(&chaseArray, &nextStart, &nextEnd, |
| &unsortable); |
| if (!next) { |
| if (!unsortable && simple->hasMove() |
| && current->verb() != SkPath::kLine_Verb |
| && !simple->isClosed()) { |
| current->addCurveTo(index, endIndex, simple, true); |
| SkASSERT(simple->isClosed()); |
| } |
| break; |
| } |
| #if DEBUG_FLOW |
| SkDebugf("%s current id=%d from=(%1.9g,%1.9g) to=(%1.9g,%1.9g)\n", __FUNCTION__, |
| current->debugID(), current->xyAtT(index).fX, current->xyAtT(index).fY, |
| current->xyAtT(endIndex).fX, current->xyAtT(endIndex).fY); |
| #endif |
| current->addCurveTo(index, endIndex, simple, true); |
| current = next; |
| index = nextStart; |
| endIndex = nextEnd; |
| } while (!simple->isClosed() && (!unsortable |
| || !current->done(SkMin32(index, endIndex)))); |
| if (current->activeWinding(index, endIndex) && !simple->isClosed()) { |
| SkASSERT(unsortable || simple->isEmpty()); |
| int min = SkMin32(index, endIndex); |
| if (!current->done(min)) { |
| current->addCurveTo(index, endIndex, simple, true); |
| current->markDoneUnary(min); |
| } |
| } |
| simple->close(); |
| } else { |
| SkOpSpan* last = current->markAndChaseDoneUnary(index, endIndex); |
| if (last && !last->fLoop) { |
| *chaseArray.append() = last; |
| } |
| } |
| current = FindChase(chaseArray, index, endIndex); |
| #if DEBUG_ACTIVE_SPANS |
| DebugShowActiveSpans(contourList); |
| #endif |
| if (!current) { |
| break; |
| } |
| } while (true); |
| } while (true); |
| return simple->someAssemblyRequired(); |
| } |
| |
| // returns true if all edges were processed |
| static bool bridgeXor(SkTDArray<SkOpContour*>& contourList, SkPathWriter* simple) { |
| SkOpSegment* current; |
| int start, end; |
| bool unsortable = false; |
| bool closable = true; |
| while ((current = FindUndone(contourList, &start, &end))) { |
| do { |
| #if DEBUG_ACTIVE_SPANS |
| if (!unsortable && current->done()) { |
| DebugShowActiveSpans(contourList); |
| } |
| #endif |
| SkASSERT(unsortable || !current->done()); |
| int nextStart = start; |
| int nextEnd = end; |
| SkOpSegment* next = current->findNextXor(&nextStart, &nextEnd, &unsortable); |
| if (!next) { |
| if (!unsortable && simple->hasMove() |
| && current->verb() != SkPath::kLine_Verb |
| && !simple->isClosed()) { |
| current->addCurveTo(start, end, simple, true); |
| SkASSERT(simple->isClosed()); |
| } |
| break; |
| } |
| #if DEBUG_FLOW |
| SkDebugf("%s current id=%d from=(%1.9g,%1.9g) to=(%1.9g,%1.9g)\n", __FUNCTION__, |
| current->debugID(), current->xyAtT(start).fX, current->xyAtT(start).fY, |
| current->xyAtT(end).fX, current->xyAtT(end).fY); |
| #endif |
| current->addCurveTo(start, end, simple, true); |
| current = next; |
| start = nextStart; |
| end = nextEnd; |
| } while (!simple->isClosed() && (!unsortable || !current->done(SkMin32(start, end)))); |
| if (!simple->isClosed()) { |
| SkASSERT(unsortable); |
| int min = SkMin32(start, end); |
| if (!current->done(min)) { |
| current->addCurveTo(start, end, simple, true); |
| current->markDone(min, 1); |
| } |
| closable = false; |
| } |
| simple->close(); |
| #if DEBUG_ACTIVE_SPANS |
| DebugShowActiveSpans(contourList); |
| #endif |
| } |
| return closable; |
| } |
| |
| // FIXME : add this as a member of SkPath |
| bool Simplify(const SkPath& path, SkPath* result) { |
| #if DEBUG_SORT || DEBUG_SWAP_TOP |
| gDebugSortCount = gDebugSortCountDefault; |
| #endif |
| // returns 1 for evenodd, -1 for winding, regardless of inverse-ness |
| SkPath::FillType fillType = path.isInverseFillType() ? SkPath::kInverseEvenOdd_FillType |
| : SkPath::kEvenOdd_FillType; |
| |
| // turn path into list of segments |
| SkTArray<SkOpContour> contours; |
| SkOpEdgeBuilder builder(path, contours); |
| if (!builder.finish()) { |
| return false; |
| } |
| SkTDArray<SkOpContour*> contourList; |
| MakeContourList(contours, contourList, false, false); |
| SkOpContour** currentPtr = contourList.begin(); |
| result->setFillType(fillType); |
| result->reset(); |
| if (!currentPtr) { |
| return true; |
| } |
| SkOpContour** listEnd = contourList.end(); |
| // find all intersections between segments |
| do { |
| SkOpContour** nextPtr = currentPtr; |
| SkOpContour* current = *currentPtr++; |
| if (current->containsCubics()) { |
| AddSelfIntersectTs(current); |
| } |
| SkOpContour* next; |
| do { |
| next = *nextPtr++; |
| } while (AddIntersectTs(current, next) && nextPtr != listEnd); |
| } while (currentPtr != listEnd); |
| // eat through coincident edges |
| CoincidenceCheck(&contourList, 0); |
| FixOtherTIndex(&contourList); |
| SortSegments(&contourList); |
| #if DEBUG_ACTIVE_SPANS || DEBUG_ACTIVE_SPANS_FIRST_ONLY |
| DebugShowActiveSpans(contourList); |
| #endif |
| // construct closed contours |
| SkPathWriter simple(*result); |
| if (builder.xorMask() == kWinding_PathOpsMask ? bridgeWinding(contourList, &simple) |
| : !bridgeXor(contourList, &simple)) |
| { // if some edges could not be resolved, assemble remaining fragments |
| SkPath temp; |
| temp.setFillType(fillType); |
| SkPathWriter assembled(temp); |
| Assemble(simple, &assembled); |
| *result = *assembled.nativePath(); |
| result->setFillType(fillType); |
| } |
| return true; |
| } |