computeIntersectsForChain6 method

void computeIntersectsForChain6(int start0, int end0, MonotoneChainEdge mce, int start1, int end1, SegmentIntersector ei,)

Implementation

void computeIntersectsForChain6(int start0, int end0, MonotoneChainEdge mce,
    int start1, int end1, SegmentIntersector ei) {
//Debug.println("computeIntersectsForChain:" + p00 + p01 + p10 + p11);

  // 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;

  // Assert: mid != start or end (since we checked above for end - start <= 1)
  // check terminating conditions before recursing
  if (start0 < mid0) {
    if (start1 < mid1)
      computeIntersectsForChain6(start0, mid0, mce, start1, mid1, ei);
    if (mid1 < end1)
      computeIntersectsForChain6(start0, mid0, mce, mid1, end1, ei);
  }
  if (mid0 < end0) {
    if (start1 < mid1)
      computeIntersectsForChain6(mid0, end0, mce, start1, mid1, ei);
    if (mid1 < end1)
      computeIntersectsForChain6(mid0, end0, mce, mid1, end1, ei);
  }
}