On Fri, Apr 11, 2008 at 5:47 AM, 80n <[EMAIL PROTECTED]> wrote: > You can have any shaped bbox you like as long as it is a rectangle ;) > > Can anyone point me to a good algorithm for selecting points within an > arbitrary polygon? > > 80n
I don't have it in pseudocode, but one I've heard of casts a ray (horizontal is common) out from the point being tested and then checks the intersection of that ray against each segment of the polygon. If the total number of intersections is odd, then the point lies inside the polygon. If the number is even, then it's outside. This works for holes in a polygon, too. Karl
_______________________________________________ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/talk
