Re: point inside polygon

["Klaus Scipal" <kscipal(at)ipf.tuwien.ac.at>]

t'x for the fast reply

the algorithm works fine until the point is lying on the polygon. in such a
case the algorithm returns sometimes in and sometimes out. what i am looking
for is an algorithm which discerns  if a point is lying on the polygon and
give only one answer either in or out but not one time in and the next time
out.

klaus



David Fanning <davidf@dfanning.com> wrote in message
MPG.132d7933449f62cc989a79@news.frii.com">news:MPG.132d7933449f62cc989a79@news.frii.com...
> Klaus Scipal (kscipal@ipf.tuwien.ac.at) writes:
> > does anyone know of an algorithm which determines if a point lies in a
> > polygon or not
>
> Here is an article that describes one method. If this
> doesn't work for you, let me know. People have sent me
> other algorithms that I have around here someplace. :-(
>
>    http://www.dfanning.com/tips/point_in_polygon.html
>
> Cheers,
>
> David
>
> --
> David Fanning, Ph.D.
> Fanning Software Consulting
> Phone: 970-221-0438 E-Mail: davidf@dfanning.com
> Coyote's Guide to IDL Programming: http://www.dfanning.com/
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