[Proj] Re: [kergis_bugs] Re: What proj library version is best?
gerald.evenden at verizon.net
Mon Jul 5 20:00:11 EDT 2004
This discussion reminds me of the email interaction Frank Warmerdam and
had about what should be included in a projection library. My position
and still is, that *only* the projection (conversion between geographic
cartesian space) is the domain of the library. All non-projection
datum shifts and x-y-z transformations are separate and unrelated
and belong in their own library systems.
The reason for this is twofold: 1) projections have uses that do not
datums and their is no reason to burden these uses with elements that
not involved and 2) developers often only have expertise in only one of
areas and should not have to burden themselves with library maintenance
involving unfamiliar elements.
I may be partly to blame for the tendency to combine projection and
manipulation software by including the 'nad2nad' program with the
PROJ.4 distributions. But this was included as an example of how to use
the projection library and used by our local shop for datum operations.
I believe Frank and I did reach a consensus but he has not had time to
redo Remotesensing software to conform to the more recent libproj4
that I support. The last I checked, libproj4 has several more
(~135 total) than the Remotesensing version including some newly
I believe a great deal of the apparent current chaos could have been
avoided by maintaining pristine PROJ.4 libraries and not indulging in
parochial additions that diminish the ease of the importing of later
Jerry and the low riders: Daisy Mae and Joshua
More information about the Proj