[Gdal-dev] ogr2ogr Default Output SRS

[Frank Warmerdam]

Martin Spott wrote:
> Frank,
> 
>> However, the solution, I think would be for OGR to:
> [...]
>>   o Provide a mechanism (a layer creation option for instance) so
>>     that the user can force use of a particular SRID whether OGR
>>     thinks the coordinate systems match or not.
> 
> Sounds good - well, I thought that
> 
>   # ~> ogr2ogr [...] -t_srs 'EPSG:4326
> 
> does this already !?


Martin,

The -t_srs switch causes EPSG:4326 to be expanded into a full well
known text representation.  It is that well known text representation
that is searched for in spatial_ref_sys.  I would also stress that SRID
is not the same as EPSG in general.  Though it just happens that the SRID
of all predefined spatial reference systems in postgis happens to have
matching values with the EPSG ids.  But that doesn't mean they are always
a 1:1 mapping.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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