[gdal-dev] Call to users and devs - ESRI .prj files needed for testing

Etienne Tourigny etourigny.dev at gmail.com
Fri Dec 2 11:25:00 EST 2011

On Fri, Dec 2, 2011 at 2:00 PM, Martin Daly <Martin.Daly at cadcorp.com> wrote:
>> Martin, thanks for this reference!
>> It seems that the dattrans.htm file contains datum transformations used
>> by ESRI, with a number of methods.
>> Would it make any sense to use that information (using a new derived
>> .csv file) to add TOWGS84 parameters to ESRI WKT definitions, instead
>> of using the ones defined in gcs.csv?
> I couldn't really say; it would depend on what you are trying to achieve.
> However, it is my understanding that you are safe in assuming that *if* the WKT matches one of these standard ones, *and* the ESRI code matches an EPSG one, that the EPSG definition is being used (or at least intended). *If* I am right then you should be able to use the GDAL definition directly, instead of trying to morph one to the other.

I'm not sure I understand.  " one of these standard ones" refers to
the WKT definitions by ESRI?  In that case, we could compare the given
WKT (in .prj file), and lookup the associated ESRI code, matching it
to EPSG code.

Are you suggesting that we could use the GDAL definition (as derived
from importFromEPSG()), without doing the morphFromESRI in this case?

> Martin
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