// intersect the end of the cubic with the other. Try lines from the end to control and opposite // end to determine range of t on opposite cubic. static void intersectEnd(const SkDCubic& cubic1, bool start, const SkDCubic& cubic2, const SkDRect& bounds2, SkIntersections& i) { SkDLine line; int t1Index = start ? 0 : 3; line[0] = cubic1[t1Index]; // don't bother if the two cubics are connnected SkTDArray<double> tVals; // OPTIMIZE: replace with hard-sized array for (int index = 0; index < 4; ++index) { if (index == t1Index) { continue; } SkDVector dxy1 = cubic1[index] - line[0]; dxy1 /= SkDCubic::gPrecisionUnit; line[1] = line[0] + dxy1; SkDRect lineBounds; lineBounds.setBounds(line); if (!bounds2.intersects(&lineBounds)) { continue; } SkIntersections local; if (!local.intersect(cubic2, line)) { continue; } for (int idx2 = 0; idx2 < local.used(); ++idx2) { double foundT = local[0][idx2]; if (approximately_less_than_zero(foundT) || approximately_greater_than_one(foundT)) { continue; } if (local.pt(idx2).approximatelyEqual(line[0])) { if (i.swapped()) { // FIXME: insert should respect swap i.insert(foundT, start ? 0 : 1, line[0]); } else { i.insert(start ? 0 : 1, foundT, line[0]); } } else { *tVals.append() = local[0][idx2]; } } } if (tVals.count() == 0) { return; } QSort<double>(tVals.begin(), tVals.end() - 1); double tMin1 = start ? 0 : 1 - LINE_FRACTION; double tMax1 = start ? LINE_FRACTION : 1; int tIdx = 0; do { int tLast = tIdx; while (tLast + 1 < tVals.count() && roughly_equal(tVals[tLast + 1], tVals[tIdx])) { ++tLast; } double tMin2 = SkTMax<double>(tVals[tIdx] - LINE_FRACTION, 0.0); double tMax2 = SkTMin<double>(tVals[tLast] + LINE_FRACTION, 1.0); int lastUsed = i.used(); intersect(cubic1, tMin1, tMax1, cubic2, tMin2, tMax2, 1, i); if (lastUsed == i.used()) { tMin2 = SkTMax<double>(tVals[tIdx] - (1.0 / SkDCubic::gPrecisionUnit), 0.0); tMax2 = SkTMin<double>(tVals[tLast] + (1.0 / SkDCubic::gPrecisionUnit), 1.0); intersect(cubic1, tMin1, tMax1, cubic2, tMin2, tMax2, 1, i); } tIdx = tLast + 1; } while (tIdx < tVals.count()); return; }
void SkIntersections::cubicNearEnd(const SkDCubic& cubic1, bool start, const SkDCubic& cubic2, const SkDRect& bounds2) { SkDLine line; int t1Index = start ? 0 : 3; double testT = (double) !start; // don't bother if the two cubics are connnected static const int kPointsInCubic = 4; // FIXME: move to DCubic, replace '4' with this static const int kMaxLineCubicIntersections = 3; SkSTArray<(kMaxLineCubicIntersections - 1) * kMaxLineCubicIntersections, double, true> tVals; line[0] = cubic1[t1Index]; // this variant looks for intersections with the end point and lines parallel to other points for (int index = 0; index < kPointsInCubic; ++index) { if (index == t1Index) { continue; } SkDVector dxy1 = cubic1[index] - line[0]; dxy1 /= SkDCubic::gPrecisionUnit; line[1] = line[0] + dxy1; SkDRect lineBounds; lineBounds.setBounds(line); if (!bounds2.intersects(&lineBounds)) { continue; } SkIntersections local; if (!local.intersect(cubic2, line)) { continue; } for (int idx2 = 0; idx2 < local.used(); ++idx2) { double foundT = local[0][idx2]; if (approximately_less_than_zero(foundT) || approximately_greater_than_one(foundT)) { continue; } if (local.pt(idx2).approximatelyEqual(line[0])) { if (swapped()) { // FIXME: insert should respect swap insert(foundT, testT, line[0]); } else { insert(testT, foundT, line[0]); } } else { tVals.push_back(foundT); } } } if (tVals.count() == 0) { return; } SkTQSort<double>(tVals.begin(), tVals.end() - 1); double tMin1 = start ? 0 : 1 - LINE_FRACTION; double tMax1 = start ? LINE_FRACTION : 1; int tIdx = 0; do { int tLast = tIdx; while (tLast + 1 < tVals.count() && roughly_equal(tVals[tLast + 1], tVals[tIdx])) { ++tLast; } double tMin2 = SkTMax(tVals[tIdx] - LINE_FRACTION, 0.0); double tMax2 = SkTMin(tVals[tLast] + LINE_FRACTION, 1.0); int lastUsed = used(); if (start ? tMax1 < tMin2 : tMax2 < tMin1) { ::intersect(cubic1, tMin1, tMax1, cubic2, tMin2, tMax2, 1, *this); } if (lastUsed == used()) { tMin2 = SkTMax(tVals[tIdx] - (1.0 / SkDCubic::gPrecisionUnit), 0.0); tMax2 = SkTMin(tVals[tLast] + (1.0 / SkDCubic::gPrecisionUnit), 1.0); if (start ? tMax1 < tMin2 : tMax2 < tMin1) { ::intersect(cubic1, tMin1, tMax1, cubic2, tMin2, tMax2, 1, *this); } } tIdx = tLast + 1; } while (tIdx < tVals.count()); return; }