strategies can be used to improve the speed of this labeling, and to avoid needing to proceed further. Care will be needed where the polygons share an edge. See also Sutherland–Hodgman clipping algorithm Vatti clipping algorithm Greiner–Hormann clipping algorithm References Weiler, Kevin and Atherton, Peter. "Hidden Surface Removal using Polygon Area Sorting", Computer Graphics, 11(2):214-222, 1977. Polygon clipping algorithms