[Qgis-user] Multipolygons with errors ?

[Goyo]

2013/3/30 Hugues François <hugues.francois at irstea.fr>:
> Hello,
>
> I'm back after few time because of work and because I had to look deeper at OGC spec. to give a right answer.
>
> After I read it the implementation standard (http://www.opengeospatial.org/standards/sfa) I definitively think the union of two polygons sharing a limited number of points result in a valid multipolygon since a multipolygon is defined as their elements' *interior* may not intersect and may touch at only a finite number of points. Furthermore, fig 12 and 17, draw an example similar to my case study to illustrate respectively an invalid polygon and (17c) a valid multipolygon.
>
> When QGis validity checker throw an error of this kind of multipolygon, I think it is wrong. Should I report a bug ?

Hello Huges,

yes, the geometry is indeed valid. I also checked that spatialite
reports no errors on (a simplified verision of) it while QGIS does,
which seems like a bug to me.

Goyo