/// <summary> /// /// </summary> /// <param name="chainIndex0"></param> /// <param name="mce"></param> /// <param name="chainIndex1"></param> /// <param name="si"></param> public void ComputeIntersectsForChain(int chainIndex0, MonotoneChainEdge mce, int chainIndex1, SegmentIntersector si) { ComputeIntersectsForChain(startIndex[chainIndex0], startIndex[chainIndex0 + 1], mce, mce.startIndex[chainIndex1], mce.startIndex[chainIndex1 + 1], si); }
/// <summary> /// /// </summary> /// <param name="edges0"></param> /// <param name="edges1"></param> /// <param name="si"></param> public override void ComputeIntersections(IList <Edge> edges0, IList <Edge> edges1, SegmentIntersector si) { foreach (var edge0 in edges0) { foreach (var edge1 in edges1) { ComputeIntersects(edge0, edge1, si); } } }
/// <summary> /// /// </summary> /// <param name="start0"></param> /// <param name="end0"></param> /// <param name="mce"></param> /// <param name="start1"></param> /// <param name="end1"></param> /// <param name="ei"></param> private void ComputeIntersectsForChain(int start0, int end0, MonotoneChainEdge mce, int start1, int end1, SegmentIntersector ei) { // terminating condition for the recursion if (end0 - start0 == 1 && end1 - start1 == 1) { ei.AddIntersections(e, start0, mce.e, start1); return; } // nothing to do if the envelopes of these chains don't overlap if (!Overlaps(start0, end0, mce, start1, end1)) { return; } // the chains overlap, so split each in half and iterate (binary search) int mid0 = (start0 + end0) / 2; int mid1 = (start1 + end1) / 2; // check terminating conditions before recursing if (start0 < mid0) { if (start1 < mid1) { ComputeIntersectsForChain(start0, mid0, mce, start1, mid1, ei); } if (mid1 < end1) { ComputeIntersectsForChain(start0, mid0, mce, mid1, end1, ei); } } if (mid0 < end0) { if (start1 < mid1) { ComputeIntersectsForChain(mid0, end0, mce, start1, mid1, ei); } if (mid1 < end1) { ComputeIntersectsForChain(mid0, end0, mce, mid1, end1, ei); } } }