[gdal-dev] WKT for epsg:3857 generated by epsg_tr.py

[Pepijn Van Eeckhoudt]

When running 'epsg_tr.py -wkt 3857', gdal produces the WKT listed below. 
I believe the projection that is stated in the WKT is incorrect though. 
The combination of WGS 84 as base geogcs with Mercator_1SP as projection 
means that the regular ellipsoidal Mercator projection will be used 
which is not correct for web mercator.

In the EPSG database 3857 is defined as using the projection 'Popular 
Visualisation Pseudo Mercator' projection which is distinct from the 
regular mercator projection. It's equivalent to 'apply spherical 
mercator to ellipsoidal coordinates'. To indicate this distinction in 
the WKT I think the projection should be something different than 
'Mercator_1SP'. Mercator_1SP_Spherical, Mercator_1SP_Google or 
Popular_Visualisation_Pseudo_Mercator for instance.

Is my understanding of this correct?

Pepijn Van Eeckhoudt

PROJCS["WGS 84 / Pseudo-Mercator",
     GEOGCS["WGS 84",
         DATUM["WGS_1984", SPHEROID["WGS 
84",6378137,298.257223563,AUTHORITY["EPSG","7030"]], 
AUTHORITY["EPSG","6326"]],
         PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],
         UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],
         AUTHORITY["EPSG","4326"]],
     PROJECTION["Mercator_1SP"],
     PARAMETER["central_meridian",0],
     PARAMETER["scale_factor",1],
     PARAMETER["false_easting",0],
     PARAMETER["false_northing",0],
     UNIT["metre",1,
         AUTHORITY["EPSG","9001"]],
     AXIS["X",EAST],
     AXIS["Y",NORTH],
     AUTHORITY["EPSG","3857"]]