PolyNodes are encapsulated within a PolyTree container, and together provide a data structure representing the parent-child relationships of polygon contours returned by Clipper's Execute method.
A PolyNode object represents a single polygon. Its IsHole property indicates whether it's an outer or a hole. PolyNodes may own any number of PolyNode children (Childs), where children of outer polygons are holes, and children of holes are (nested) outer polygons.
Overview, Clipper.Execute, PolyTree
Copyright ©2010-2014 Angus Johnson - Clipper 6.2.0 - Help file built on 16-October-2014