[mapguide-internals] PATCH 1468: "Unset the EPSG code when cloning a Coordinate System entity"

[Andre Barth]

Hi all,

can you please have a look at patch 1468 http://trac.osgeo.org/mapguide/ticket/1468 and the patch attached to it.

It's a rather minor enhancement in how the EPSG code is handled when a coordinate system entity (i.e. ellipsoid, datum, coordinate system, geodetic transformation, geodetic path) is cloned/duplicated. Currently, CsMap's NameMapper component does not consider the EPSG code anyway that might have been stored with a definition in one of the dictionaries but rather uses the static information that's built into it (See MgCoordinateSystemFactory::CreateFromCode).

Cloning an CS entity and then writing it back to the dictionaries makes it editable (unlike to the definitions that are built by CsMap's dictionary compiler) - i.e. the parameters can modified and written back. Unsetting the EPSG code after a CreateClone() reduces the likelihood of 'chaos' in the dictionaries where the same EPSG code exists for varying definitions.

Thanks,
André