[GRASS5] 5.7: new GUI guided auto-creation of locations

[Paul Kelly]

Hello Markus

On Wed, 28 Apr 2004, Markus Neteler wrote:

> Hi again,
>
> Andrea Antonello and me have enhanced the GUI startup
> of GRASS 5.7. Now a new button is available to
> create a location by just entering the appropriate
> EPSG code. EPSG (European Petroleum Survey Group, www.epsg.org)
> is providing a database of thousands of projections,
> these codes are also used in PROJ4.
> The new GUI enhancement provides another button to
> list the EPSG codes file from PROJ4 for projection
> selection.

I would add that the list of EPSG codes actually used by g.proj when
creating the location *seems* to be $GISBASE/etc/ogr_csv/pcs.csv (nothing
in GRASS directly reads this file but it is looked up by the underlying
OGR functions called from g.proj).
This file is associated with the GDAL/OGR distribution but there
is now a copy supplied with GRASS, which can be updated if there are any
bugs found in it. In the source tree it is in the lib/proj directory.
I didn't try the new system yet but I saw a hard-coded path
/usr/local/share/proj/epsg in epsg_option.tcl which doesn't look too
portable.

I had an idea for an improved startup that would use the full capabilities
of g.proj, r.in.gdal and v.in.ogr to allow giving the name of a
georeferenced file on which the location would be created, EPSG code etc.
I don't think it should be necessary to set up dummy locations in order to
run g.proj when it is all working properly.

But that is for another day (or month. or year. :-) )

> After entering into the new location, the boundary coordinates
> have to be adjusted or 'r.in.gdal -e' has to be used to
> update the DEFAULT_WIND file.

Is there any reason why the GUI can't do this as well? ISTR there is no
interactive g.region in 5.7 anyway.

Paul