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

[Markus Neteler]

On Wed, Apr 28, 2004 at 07:26:45PM +0100, Paul Kelly wrote:
> 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.

Good idea - I didn't remember that file. In fact the GDAL/OGR
version seems to be free of the mentioned errors with prime meridian.

> 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.

Right - such a "pure" GRASS solution is much better.

> 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.

That would simplify my script...
> But that is for another day (or month. or year. :-) )

... we stay tuned :-)

> > 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.

Time and money - of course it is technically possible
to also ask the location boundaries and a default raster resolution.
It mostly depends on Andrea or another person with tcl/tk skills.

Markus