[geos-devel] polygon with overlapping edges

[Sandro Santilli]

On Fri, Apr 13, 2012 at 11:52:20AM +0200, Jasmin FORMONT wrote:
> Hi everyone
> 
> I am currently testing some GEOS features.
> I am having trouble with polygons with overlapping edges. You can see attached an example of what I use (dxf file).
> When loaded as a GEOS polygon, it is considered not valid. Is there any way to avoid this problem ? Maybe a GEOS function making this polygon
> valid by slightly moving some points ?
> 
> I have no influence on the input polygons, they are produced like that by our production chain and changing this is not an option.
> 
> thanks for any tip

Try a buffer with distance 0.
Or try PostGIS 2.0 (has an ST_MakeValid function).

--strk;

  ,------o-. 
  |   __/  |    Delivering high quality PostGIS 2.0 !
  |  / 2.0 |    http://strk.keybit.net - http://vizzuality.com
  `-o------'