You're partly right, Regina. Simplifypreserve does work on a collection
basis. However, it is designed to prevent overlaps from occuring, but
not "non-overlaps". So even if you collect the polygons into a
GeometryCollection, gaps can still occur - this doesn't violate the
notion of "topology" that is preserved by simplifypreserve.
One way to prevent gaps from happening between coincident linestrings is
to reduce them to a single linestring. So to simplify a coverage of
polygons, it should be possible to dissolve them into a single-line
coverage as a MultiLineString, simplify that, and then polygonize the
result.
I haven't tested this, but that's the theory...
Paragon Corporation wrote:
The reason I say no is that that if you collect the geometries first and
then simplify, I think even simplifypreserve will loop thru each geometry
anyway and simplify. Though I'm not absolutely positive of that. So the
whole exercise of collect simplify dump is a bit fruitless if that was your
intention. Not a bad thought and maybe you are right so maybe someone can
correct me on that.
--
Martin Davis
Senior Technical Architect
Refractions Research, Inc.
(250) 383-3022
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