union, difference and xor) on polygons in 2D space. There are no
restrictions on either the number nor the type of polygon that can be
clipped. They can have holes, be self-intersecting and even have coincident
edges. The library also performs polygon offsetting
WWW: http://www.angusj.com/delphi/clipper.php
PR: ports/175845
Submitted by: Martin Dieringer <martin.dieringer@gmx.de>