[Geoserver-devel] [jira] Created: (GEOS-1037) Projection handling not correct for Stereographic projection

Projection handling not correct for Stereographic projection
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                 Key: GEOS-1037
                 URL: http://jira.codehaus.org/browse/GEOS-1037
             Project: GeoServer
          Issue Type: Bug
          Components: Global
    Affects Versions: 1.5.0-RC4
         Environment: Linux, Opteron processor, JDK 1.5.0
            Reporter: Alexander Paul Robin Cooper
            Assignee: Andrea Aime
             Fix For: 1.5.x

The projection defined by the following WKT worked correctly in geoserver 1.3.4, when it was placed in epsg.proprties in gt2-epsg.jar. Placing the same WKT in epsg.properties in /data/user_projections does not work - it appears that the scale factor is ignored when projecting to this projection from geographic coordinates (4326); data specified in geographic coordinates plots too far North when displayed over data held in this coordinate system. Projection from this projection to another appears to be correct, but it is difficult to verify.

I am afraid I can't leave a test case running, as I have had to revert to 1.3.4; the error is not tolerable in a production system and I don't have a test server.

Please note that this is an EPSG projection in the version of the EPSG database that is claimed to be implemented in the Geotools software. Its absence is somewhat worrying! It is not the only missing projection ; there are a group at around 3270 also missing - again, polar stereographic projections.

Incidentally, the proj string for the projection is:

+proj=stere +lon_0=0 +lat_0=-90 +lat_ts=-71 +ellps=WGS84 +datum=WGS84.

Having to use a scale factor is a very clumsy way to specify the projection, although it is equivalent.

3031=PROJCS["Antarctic Polar Stereographic",
   GEOGCS["WGS 84",
       DATUM["WGS_1984",
         SPHEROID["WGS 84",6378137,298.257223563,AUTHORITY["EPSG","7030"]],
         TOWGS84[0,0,0,0,0,0,0],
         AUTHORITY["EPSG","6326"]],
      PRIMEM["Greenwich",0, AUTHORITY["EPSG","8901"]],
      UNIT["degree",0.0174532925199433,
      AUTHORITY["EPSG","9108"]],
      AXIS["Lat",NORTH],
AXIS["Long",EAST],
AUTHORITY["EPSG","4326"]],
PROJECTION["Polar_Stereographic"],
PARAMETER["latitude_of_origin",-90],
PARAMETER["central_meridian",0],
PARAMETER["scale_factor",0.97276901289],
PARAMETER["false_easting",0],
PARAMETER["false_northing",0],
UNIT["metre",1,AUTHORITY["EPSG","9001"]],
AUTHORITY["EPSG","3031"]]

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