Hi,
The complexity of creating a new CRS is (or should be) determined by the
governance model of the CRS registration authority and nothing else (In
may view). The creation of URN's should then be automated by the
registry of that authority. It is easy to imagine an authority that
allows anyone to register ANY CRS they like - with the submitter
supplying the definition (e.g. in GML). This would afford the
registration authority some scope in automatically verifying the
definition (not sure this can be done totally), and in ensuring that two
CRS do not have the same definition etc. For example, many rectilinear
frames (what is called Engineering Coordinate Reference Systems by
Geodesist - sometimes also called Local) could be defined just by
providing the names/units/directions of the frame axes and the same for
the origin - and possibly other information (e.g. transformation matrix)
to connect this to other frames.
Ron
-----Original Message-----
From: galeon-bounces@xxxxxxxxxxxxxxxx
[mailto:galeon-bounces@xxxxxxxxxxxxxxxx] On Behalf Of Ethan Davis
Sent: October 9, 2008 1:07 PM
To: Unidata GALEON
Subject: Re: [galeon] How to map a parameterized projection to an EPSG
code
Hi Ron,
Ron Lake wrote:
Ethan:
The structure of a URN is so that you can create one - NOT so that they
are parsed for content. I think the fuzziness at the OGC in this regard
is simple mistaken.
I agree. And I think the complexity involved in the creation of one
reinforces the misunderstanding.
GML is used now in the http://www.epsg-registry.org. This registry and
the assignment of EPSG codes is controlled by the registration
authority, in this case the OGP. Another such registry could easily be
deployed assuming that someone is willing to be the registration
authority and this could have perhaps a difference governance model than
used by the OGP. The 19111 new parts will make their way into GML of
course.
Thanks Ron. I wasn't that aware of the EPSG registry (I've only perused
the MS Access stuff) or that it used GML.
Thanks,
Ethan
