/// <summary>
///
/// </summary>
/// <param name="start0"></param>
/// <param name="end0"></param>
/// <param name="mc"></param>
/// <param name="start1"></param>
/// <param name="end1"></param>
/// <param name="mco"></param>
private void ComputeOverlaps(int start0, int end0, MonotoneChain mc, int start1, int end1, MonotoneChainOverlapAction mco)
{
Coordinate p00 = _pts[start0];
Coordinate p01 = _pts[end0];
Coordinate p10 = mc._pts[start1];
Coordinate p11 = mc._pts[end1];
// terminating condition for the recursion
if (end0 - start0 == 1 && end1 - start1 == 1)
{
mco.Overlap(this, start0, mc, start1);
return;
}
// nothing to do if the envelopes of these chains don't overlap
mco.TempEnv1.Init(p00, p01);
mco.TempEnv2.Init(p10, p11);
if (! mco.TempEnv1.Intersects(mco.TempEnv2))
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)
ComputeOverlaps(start0, mid0, mc, start1, mid1, mco);
if (mid1 < end1)
ComputeOverlaps(start0, mid0, mc, mid1, end1, mco);
}
if (mid0 < end0)
{
if (start1 < mid1)
ComputeOverlaps(mid0, end0, mc, start1, mid1, mco);
if (mid1 < end1)
ComputeOverlaps(mid0, end0, mc, mid1, end1, mco);
}
}
/// <summary>
///
/// </summary>
/// <param name="mc"></param>
/// <param name="mco"></param>
public virtual void ComputeOverlaps(MonotoneChain mc, MonotoneChainOverlapAction mco)
{
ComputeOverlaps(_start, _end, mc, mc._start, mc._end, mco);
}