[postgis-users] bow-tie polygons and the like

[Frank Warmerdam]

Martin Davis wrote:
> 
> Chris Hermansen wrote:
>> I guess what is interesting is the self-intersecting and loop
>> self-intersecting polygons were built by ogr2ogr when converting from
>> ArcInfo coverages to PostGIS.
>>
>>   
> Now that *is* interesting.  Seems like maybe a bug in the ogr2ogr code?  
> Is it worth asking FW about this?

Martin,

In at least some polygon-assembly-from-arcs situations OGR just arbitrarily
connects arcs to arcs with matching end points with no regard to ambiguous
situations like bowties.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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