[mapguide-internals] PATCH 1468: "Unset the EPSG code when cloning
a Coordinate System entity"
Andre.Barth at autodesk.com
Mon Oct 18 03:42:49 EDT 2010
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.
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