[Gdal-dev] Reproject with Mapserver vs gdalwarp

[Jan Hartmann]

Frank, is there any reason why Gdal doesn't use the epsg-file? Wouldn't 
it make things easier if it did? In my experience, this double 
administration can cause problems that are very hard to detect.

Even better of course is Howard Butler's web-based approach:

http://lists.maptools.org/pipermail/gdal-dev/2007-July/013641.html

Jan

Frank Warmerdam wrote:
> José Vicente Higón wrote:
>> In both cases I was using the latest FWTools release (1.3.4)
>>
>> Why Did I get differents results in MApserver and gdalwarp?Any clue?
> 
> José,
> 
> GDAL does not generally use the PROJ.4 epsg init file.  Instead it has
> a set of .csv files with the EPSG definition information.
> 
> I think you will want to edit this line of FWTools/data/pcs.csv:
> 
> 23030,"ED50 / UTM zone 
> 30N",9001,4230,16030,9807,1,0,8805,0.9996,9201,8802,-3,9102,8801,0,9102,8807,0,9001,8806,500000,9001,,,,,, 
> 
> 
> To include include the TOWGS84 values.  Something like:
> 
> 23030,"ED50 / UTM zone 
> 30N",9001,4230,16030,9807,1,0,8805,0.9996,9201,8802,-3,9102,8801,0,9102,8807,0,9001,8806,500000,9001,-87,-98,-121,0,0,0,0 
> 
> 
> You might want to verify that GDAL is picking up the definition properly
> by entering "testepsg EPSG:23030" in the FWTools shell which will
> report the coordinate system in various forms.  Make sure that one (the
> first I think) includes the proper TOWGS84[] parameters and that they make
> it into the final PROJ.4 rendering.
> 
> Best regards,