/** @return the index of the last point in the monotone chain */
private int findChainEnd(Coordinate[] pts, int start) {
// determine quadrant for chain
int chainQuad = Quadrant.quadrant(pts[start], pts[start + 1]);
int last = start + 1;
while (last < pts.length) {
// if (last - start > 100) break;
// compute quadrant for next possible segment in chain
int quad = Quadrant.quadrant(pts[last - 1], pts[last]);
if (quad != chainQuad) break;
last++;
}
return last - 1;
}