[gdal-dev] GML / NAS code redundancy

[Even Rouault]

Le samedi 05 avril 2014 22:53:20, Martin Landa a écrit :
> Hi,
> 
> 2014-04-05 22:38 GMT+02:00 Even Rouault <even.rouault at mines-paris.org>:
> 
> [...]
> 
> > Hum, this isn't yet possible, but I can try to see if I can add support
> > for that.
> 
> thanks!
> 
> > This is really wanted. The SRS is a property of a geometry column. There
> > are cases where 2 geometry columns could have a different SRS.
> 
> Sure, but in this cases there is only one SRS defined for whole input
> file. So layer-related SRS would be enough.

This is a limitation of the GML driver (SRS detection and handling is quite 
complicated in the GML driver). But with RFC 41, there are drivers that can 
handle different SRS for each geometry column (for example PostGIS).

> BTW, do I need to specify
> SRS separately for each GMLFeatureClass?

Usually yes to be on the safe side.

> I found
> useGlobalSRSName="true" noted in the manual, but not explained.

Yes... linked to the clunky SRS handling... well it means that the first 
srsName attribute found in the file can apply to all geometries of the whole 
file.

> 
> Martin

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