[postgis-devel] GEOS2POSTGIS

[strk at refractions.net]

On Tue, Dec 14, 2004 at 09:33:17AM -0500, Carl Anderson wrote:
> strk at refractions.net wrote:
> 
> >On Mon, Dec 13, 2004 at 02:18:11PM -0500, Carl Anderson wrote:
> > 
> >
> >>I am having problems with MULTIPOLYGON types passing through GEOS2POSTGIS
> >>
> >>the routine is making a geometry collection of polygons not a multipolygon
> >>except that it labels the mess as a multipolygon
> >>
> >>
> >>for example
> >>
> >>SRID=102667;010600000005000000SRID=0;0103000000010000000500000000
> >>0000606EA1404100000020825A3441207F245077A1404153CCD639995A3441
> >>2CF237915CA14041859B332C505A344139A6505F76A140416E660BA8965A3
> >>441000000606EA1404100000020825A3441SRID=0;010300000001............
> >>
> >>not
> >>
> >>SRID=102667;0106000000050000000103000000010000000500000000
> >>0000606EA1404100000020825A3441207F245077A1404153CCD639995A3441
> >>2CF237915CA14041859B332C505A344139A6505F76A140416E660BA8965A3
> >>441000000606EA1404100000020825A3441010300000001............
> >>   
> >>
> >
> >IIRC a MULTIPOLYGON is exactly a collection of polygons
> >labeled as a multipolygon. The problem here is with SRID defined
> >inside inner geoms. 
> > 
> >
> sorry i meant a collection of lwgeom polygons as opposed to a collection 
> of OGC polygons. OGC WKB/WKT lack the tag SRID

lwgeom adds a SRID, but only at the start of each geometry,
inside SRID tags are bogus.

> 
> >I've taken a look at the 'collect' function and it failed
> >to check for compatible dimensions and srid. I've added that.
> >But how did you produce that geometry ? Solely inside GEOS ?
> >In that case we need to check it somewhere else.
> >
> > 
> >
> Postgresql:
> select difference(a.the_geom,b.the_geom) from a, b .....
> 
> current CVS is working  ok.

Weird.. as I only touched the collect() aggregate for that matter.
Are a.the_geom and b.the_geom the result of a collect() call ?
Or were you using a pretty old CVS snapshot ?

--strk;