| /* |
| * 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 "SkGeometry.h" |
| #include "SkOpEdgeBuilder.h" |
| #include "SkReduceOrder.h" |
| |
| void SkOpEdgeBuilder::init() { |
| fCurrentContour = NULL; |
| fOperand = false; |
| fXorMask[0] = fXorMask[1] = (fPath->getFillType() & 1) ? kEvenOdd_PathOpsMask |
| : kWinding_PathOpsMask; |
| #ifdef SK_DEBUG |
| SkPathOpsDebug::gContourID = 0; |
| SkPathOpsDebug::gSegmentID = 0; |
| #endif |
| fUnparseable = false; |
| fSecondHalf = preFetch(); |
| } |
| |
| void SkOpEdgeBuilder::addOperand(const SkPath& path) { |
| SkASSERT(fPathVerbs.count() > 0 && fPathVerbs.end()[-1] == SkPath::kDone_Verb); |
| fPathVerbs.pop_back(); |
| fPath = &path; |
| fXorMask[1] = (fPath->getFillType() & 1) ? kEvenOdd_PathOpsMask |
| : kWinding_PathOpsMask; |
| preFetch(); |
| } |
| |
| bool SkOpEdgeBuilder::finish() { |
| if (fUnparseable || !walk()) { |
| return false; |
| } |
| complete(); |
| if (fCurrentContour && !fCurrentContour->segments().count()) { |
| fContours.pop_back(); |
| } |
| return true; |
| } |
| |
| void SkOpEdgeBuilder::closeContour(const SkPoint& curveEnd, const SkPoint& curveStart) { |
| if (!SkDPoint::ApproximatelyEqual(curveEnd, curveStart)) { |
| fPathVerbs.push_back(SkPath::kLine_Verb); |
| fPathPts.push_back_n(1, &curveStart); |
| } else { |
| fPathPts[fPathPts.count() - 1] = curveStart; |
| } |
| fPathVerbs.push_back(SkPath::kClose_Verb); |
| } |
| |
| int SkOpEdgeBuilder::preFetch() { |
| if (!fPath->isFinite()) { |
| fUnparseable = true; |
| return 0; |
| } |
| SkAutoConicToQuads quadder; |
| const SkScalar quadderTol = SK_Scalar1 / 16; |
| SkPath::RawIter iter(*fPath); |
| SkPoint curveStart; |
| SkPoint curve[4]; |
| SkPoint pts[4]; |
| SkPath::Verb verb; |
| bool lastCurve = false; |
| do { |
| verb = iter.next(pts); |
| switch (verb) { |
| case SkPath::kMove_Verb: |
| if (!fAllowOpenContours && lastCurve) { |
| closeContour(curve[0], curveStart); |
| } |
| fPathVerbs.push_back(verb); |
| fPathPts.push_back(pts[0]); |
| curveStart = curve[0] = pts[0]; |
| lastCurve = false; |
| continue; |
| case SkPath::kLine_Verb: |
| if (SkDPoint::ApproximatelyEqual(curve[0], pts[1])) { |
| uint8_t lastVerb = fPathVerbs.back(); |
| if (lastVerb != SkPath::kLine_Verb && lastVerb != SkPath::kMove_Verb) { |
| fPathPts.back() = pts[1]; |
| } |
| continue; // skip degenerate points |
| } |
| break; |
| case SkPath::kQuad_Verb: |
| curve[1] = pts[1]; |
| curve[2] = pts[2]; |
| verb = SkReduceOrder::Quad(curve, pts); |
| if (verb == SkPath::kMove_Verb) { |
| continue; // skip degenerate points |
| } |
| break; |
| case SkPath::kConic_Verb: { |
| const SkPoint* quadPts = quadder.computeQuads(pts, iter.conicWeight(), |
| quadderTol); |
| const int nQuads = quadder.countQuads(); |
| for (int i = 0; i < nQuads; ++i) { |
| fPathVerbs.push_back(SkPath::kQuad_Verb); |
| } |
| fPathPts.push_back_n(nQuads * 2, quadPts); |
| curve[0] = quadPts[nQuads * 2 - 1]; |
| lastCurve = true; |
| } |
| continue; |
| case SkPath::kCubic_Verb: |
| curve[1] = pts[1]; |
| curve[2] = pts[2]; |
| curve[3] = pts[3]; |
| verb = SkReduceOrder::Cubic(curve, pts); |
| if (verb == SkPath::kMove_Verb) { |
| continue; // skip degenerate points |
| } |
| break; |
| case SkPath::kClose_Verb: |
| closeContour(curve[0], curveStart); |
| lastCurve = false; |
| continue; |
| case SkPath::kDone_Verb: |
| continue; |
| } |
| fPathVerbs.push_back(verb); |
| int ptCount = SkPathOpsVerbToPoints(verb); |
| fPathPts.push_back_n(ptCount, &pts[1]); |
| curve[0] = pts[ptCount]; |
| lastCurve = true; |
| } while (verb != SkPath::kDone_Verb); |
| if (!fAllowOpenContours && lastCurve) { |
| closeContour(curve[0], curveStart); |
| } |
| fPathVerbs.push_back(SkPath::kDone_Verb); |
| return fPathVerbs.count() - 1; |
| } |
| |
| bool SkOpEdgeBuilder::close() { |
| complete(); |
| return true; |
| } |
| |
| bool SkOpEdgeBuilder::walk() { |
| uint8_t* verbPtr = fPathVerbs.begin(); |
| uint8_t* endOfFirstHalf = &verbPtr[fSecondHalf]; |
| const SkPoint* pointsPtr = fPathPts.begin() - 1; |
| SkPath::Verb verb; |
| while ((verb = (SkPath::Verb) *verbPtr) != SkPath::kDone_Verb) { |
| if (verbPtr == endOfFirstHalf) { |
| fOperand = true; |
| } |
| verbPtr++; |
| switch (verb) { |
| case SkPath::kMove_Verb: |
| if (fCurrentContour) { |
| if (fAllowOpenContours) { |
| complete(); |
| } else if (!close()) { |
| return false; |
| } |
| } |
| if (!fCurrentContour) { |
| fCurrentContour = fContours.push_back_n(1); |
| fCurrentContour->setOperand(fOperand); |
| fCurrentContour->setXor(fXorMask[fOperand] == kEvenOdd_PathOpsMask); |
| } |
| pointsPtr += 1; |
| continue; |
| case SkPath::kLine_Verb: |
| fCurrentContour->addLine(pointsPtr); |
| break; |
| case SkPath::kQuad_Verb: |
| fCurrentContour->addQuad(pointsPtr); |
| break; |
| case SkPath::kCubic_Verb: |
| fCurrentContour->addCubic(pointsPtr); |
| break; |
| case SkPath::kClose_Verb: |
| SkASSERT(fCurrentContour); |
| if (!close()) { |
| return false; |
| } |
| continue; |
| default: |
| SkDEBUGFAIL("bad verb"); |
| return false; |
| } |
| pointsPtr += SkPathOpsVerbToPoints(verb); |
| SkASSERT(fCurrentContour); |
| } |
| if (fCurrentContour && !fAllowOpenContours && !close()) { |
| return false; |
| } |
| return true; |
| } |