Igor Brejc wrote: > http://en.wikipedia.org/wiki/Point_in_polygon > > Igor > That algorithm should be okay for the common use case. Just keep in mind that polygons for some countries are quite complicated and may be comprised of multiple separate polygons (eg. islands). I think the point in polygon algorithm will work if the polygons don't overlap, but if they do it can give false results. I suspect the http://www.maproom.psu.edu/dcw/ polygons will play nicely but I don't know for sure.
The current osmosis polygon engine supports overlapping polygons. It also allows polygon "subtraction" where a polygon can be removed from an existing polygon. This is all handled by the Java2D APIs so I don't know much about the actual implementation. _______________________________________________ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/talk
