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Subject: [ggl] Considering GEOS
From: Barend Gehrels (Barend.Gehrels)
Date: 2009-04-15 03:48:12

Hi Mateusz,

> When I found GGL and started to work with it, I got an idea of porting
> some of GEOS [1] algorithms to GGL.
Actually I had seen that and had to think about it. Personally I don't
think it is really useful to us. Our approach is totally different from
theirs. In the past I've looked to some implementations (not GEOS but
e.g. geometryalgorithms). It is possible but in the end they turn out to
be completely rewritten. It is justed an "influence" like reading an

Besides that I'm afraid that if we "copy" GEOS code we'll also get (a
part of) its performance.

Finally there is the license issue.

It might seem attractive because they have much more (= all OGC)
operations implemented. However, if we continue the step of the new
segment intersection, together with the (completely revised) steps in
the polygon clip (Weiler Atherton graph traversal), we have
touch,overlaps,intersects,relate,disjoint,equals,intersection,union and
buffer all implemented so it then becomes really useful. More about this
will follow.


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