[gdal-dev] org2ogr, KML, and srs definition

[Brent Fraser]

I have some shapefiles I thought I would look at in Google Earth, so I 
used ogr2ogr (v1.8.1) to convert them to KML:

ogr2ogr -f "KML" Lines_OGR.kml Lines.shp

but they appeared about 100 meters Northeast of my expectation, leading 
me to believe there was a Datum problem.

ogrinfo reported (since there is a .prj file created by ArcMap):

Layer SRS WKT:
PROJCS["UTM_Zone_35_Northern_Hemisphere",
     GEOGCS["GCS_Geographic Coordinate System",
         DATUM["EUROPEAN_DATUM_1950",
             
SPHEROID["International_1909_Hayford_Intl_1924",6378388,297.0000000284015]],
         PRIMEM["Greenwich",0],
         UNIT["Degree",0.017453292519943295]],
     PROJECTION["Transverse_Mercator"],
     PARAMETER["latitude_of_origin",0],
     PARAMETER["central_meridian",27],
     PARAMETER["scale_factor",0.9996],
     PARAMETER["false_easting",500000],
     PARAMETER["false_northing",0],
     UNIT["Meter",1]]

note the ED50, which is correct for my shapefiles.  After a few attempts 
experimenting, it was only when I used -s_srs AND -t_srs on the command 
line the features were shown where I expected them:

ogr2ogr -s_srs "EPSG:23035" -t_srs "EPSG:4326"...

The part that bothered me was there was no message from ogr2ogr warning 
me about source/target SRS issues.  It seems counter-intuitive since 
ogrinfo was able to intreprete the .prj file of the source data, and the 
only (?) allowable SRS of KML is EPSG:4326.

It this a known issue (other than a related 
http://trac.osgeo.org/gdal/ticket/2271)?

-- 
Best Regards,
Brent Fraser