Sounds good to me. I have added two methods, simplify and
topology_preserve_simplify to the base geometry class in r1493. I
wasn't sure about the naming of the methods. The second method is a
little long, and I would normally use camel case, but I think this is
the Shapely standard. Please correct me if this is wrong though. I
copied a few of the tests from GEOS and they seem to work fine. Is
this what you were thinking for support in 1.2? I would agree that in
2.0 we could add something better since it might not be a OGC
standard. This should allow people to start using it though.

-Aron

On Mon, Nov 9, 2009 at 2:13 PM, Sean Gillies <[email protected]> wrote:
> On Nov 9, 2009, at 7:43 PM, Helge Jensen wrote:
>
>> I am doing simplification of polygons for storage and calculation
>> efficiency. and would like to do polygon-simplification.
>>
>> Currently I use the postgis function ST_SimplifyPreserveTopology to
>> do the
>> simplification, however the dataset is growing large and I would
>> like to
>> move the pre-processing away from the database which should be busy
>> answering real-time queries.
>>
>> I am already doing pre-processing (parsing from list(x,y,level),
>> rasterisation and polygonization) in python (and distributed too,
>> thanks to
>> the new multiprocessing module).
>>
>> So, I spotted the shapely bindings for GEOS, and the thread
>> http://www.mail-archive.com/[email protected]/msg00510.htmlwhich
>> indicated that a Douglas-Peucker variant was easily accessible for me
>> and my pre-processing code.
>>
>> However I have checked out the trunk and not been able to "from
>> shapely.geos.ops import simplify", or even find the shapely.geos.ops
>> module
>
> Hi,
>
> In that email, I'd suggested that in the trunk I *might* move the
> simplify method to a function in an ops module, or provide a
> complementary function. The work hasn't been done yet.
>
> Instead of using the trunk, I strongly recommend trying the 1.2
> branch. Aron Bierbaum has put a lot of work into it, tests are
> passing, and I think we're pretty close to where we can start to
> consider a preview release. A geometry simplify method or its
> functional counterpart isn't implemented there yet, but wouldn't be
> much work, and would be a lot closer to being deployable than the
> Shapely trunk.
>
> http://svn.gispython.org/svn/gispy/Shapely/branches/1.2
>
> Aron, what do you think about simplification for 1.2?
>
> --
> Sean Gillies
> Programmer
> Institute for the Study of the Ancient World
> New York University
>
> _______________________________________________
> Community mailing list
> [email protected]
> http://lists.gispython.org/mailman/listinfo/community
>
_______________________________________________
Community mailing list
[email protected]
http://lists.gispython.org/mailman/listinfo/community

Reply via email to