[gdal-dev] Datum Shifts with OSR.CoordinateTransform

Armin Burger armin.burger at gmx.net
Tue May 10 05:26:42 EDT 2011


In newer versions of the WKT definition there is sometimes a TOWGS84[...] tag included which contains the 7 shifting parameters, but I don't know if this is already a standard notation and if GDAL automatically takes this into account when found.

What should normally work is to use the Proj4 notation which includes the tag 

and then define the projection via the method


-------- Original-Nachricht --------
> Datum: Mon, 9 May 2011 20:07:23 -0700 (PDT)
> Von: srweal <srweal at gmail.com>
> An: gdal-dev at lists.osgeo.org
> Betreff: [gdal-dev] Datum Shifts with OSR.CoordinateTransform

> Hi all,
> I'm using the C# wrapper and GDAL/OGR binaries from Tamas' repository
> (http://vbkto.dyndns.org:1280/sdk/) and am trying to do coordinate
> transformation that includes a datum shift on a geometry.  
> I'm wanting to understand how I can control what shift parameters are used
> when calling the MyGeometry.Transform(MyTransform) method.  
> I have been creating the CoordinateTransform by using the basic
> constructor
> (i.e. new CoordinateTransform(SourceSR, TargetSR)) but this doesn't give
> me
> any control over the shift.  Do I need to define the shift parameters on
> the
> actual SourceSR and TargetSR?  If so, how is this best done.
> Currently I'm creating the SourceSR via the ImportFromWkt() method and
> obtaining the WKT from spatialreference.org.
> Thanks for any advice, examples or links you can provide with more
> information.
> Steve 
> --
> View this message in context:
> http://osgeo-org.1803224.n2.nabble.com/Datum-Shifts-with-OSR-CoordinateTransform-tp6346391p6346391.html
> Sent from the GDAL - Dev mailing list archive at Nabble.com.
> _______________________________________________
> gdal-dev mailing list
> gdal-dev at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/gdal-dev

Empfehlen Sie GMX DSL Ihren Freunden und Bekannten und wir
belohnen Sie mit bis zu 50,- Euro! https://freundschaftswerbung.gmx.de

More information about the gdal-dev mailing list