[gdal-dev] Spatialite geometry format

[Simon Lyngby Kokkendorff]

Hi Even,

I think you're right. The transformation seems to alter the geometry type
somehow - need to debug a little more to see exactly what's going on.

 Thanks,
Simon



On Mon, May 6, 2013 at 3:50 PM, Even Rouault
<even.rouault at mines-paris.org>wrote:

> Selon Simon Lyngby Kokkendorff <silyko at gmail.com>:
>
> > Hi List,
> >
> >    I am programming an application which can transform ogr-datasources
> > (using our own transformation library). In that process I use ogr
> (version
> > 1.10)  via the c-api to read and write datasources - usually it works
> like
> > a charm. However, when I try to write an output spatialite datasource, I
> > run into this error:
> >
> > sqlite3_step() failed:
> >
> > points2.GEOMETRY violates Geometry constraint [geom-type or SRID not
> > allowed] (19)
> >
> >
> > I am not sure whether it's an issue with the SRID or the geom-type /
> > format. I also see on the ogr-drivers page, that spatialite use a speciel
> > (wkb like?) format for the geometry column.
>
> Yes, but this is an implementation detail from the point of view of users
> of
> OGR, that is hidden by the OGR API.
>
> >
> >
> > What I usually do is to clone an input feature, clone the geometry:
> >
> >
> > hGeometry = OGR_G_Clone(OGR_F_GetGeometryRef(hFeature_out));
> >
> >
> > perform some transformations and set the geometry (again):
> >
> >
> > OGR_F_SetGeometryDirectly(hFeature_out,hGeometry);
> >
> >
> > While this works for (most) input and output datasources, it produces the
> > error above for spatialite output. Perhaps because the internal geometry
> > reperesentation is wrong, or there is some other more strict check of
> > output srs - e.g. should I use  OGR_G_AssignSpatialReference to assign
> the
> > output spatial reference to the geometry?
> >
> >
> > Is there something obvious that I am missing here?
>
> The driver takes responsibility of assigning the SRID automatically from
> the
> layer SRS. So the error is likely due to an attempt of inserting a geometry
> whose type doesn't match the layer geometry type. Spatialite is really
> strict on
> that: POLYGON != MULTIPOLYGON, and (perhaps I'm not sure) 2D != 2.5D
>
> >
> >
> > Best Regards,
> >
> > Simon Kokkendorff,  Danish Geodata Agency
> >
>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/gdal-dev/attachments/20130506/42bf70a6/attachment-0001.html>