[GRASS5] Re: GPJ_osr_to_grass()

[Paul Kelly]

Hello Markus

On Fri, 5 Dec 2003, Markus Neteler wrote:

> Hello Paul,
>
> if you don't mind... I would like to ask you if you
> see a chance to revisit GPJ_osr_to_grass() again?
>
> It were great to have v.in.ogr capable of generating
> locations. The updated v.in.ogr/main.c I have written
> (maybe it works) but it is lacking above function.

I have made an attempt at this and put it into the 5.7 CVS now. The new
updated g.proj will also generate locations (although it doesn't set the
region like r.in.gdal does).

It can also set up locations using EPSG codes (passed in the form of a
PROJ.4 projection description---see the description.html for g.proj for
an example). To do this it needs some GDAL CSV files so
I have placed a local copy of these in the GRASS tree. I'm not sure which
ones exactly are needed so I have put nine in. Possibly we could update
these with improved versions later.

A nice side effect of this is that if the datum is specified by the EPSG
code but there are no datum transformation parameters given, if GRASS
recognises the datum name then g.proj will interactively prompt for
parameters using those already in the GRASS datumtransform.table.

At some stage it may also be possible to use g.proj to make an improved
startup for a new location (and new user), avoiding the use of g.setproj
if a geo-referenced file is available. But that is for somebody else to do
if they want.

You will probably remember that it was the bugfix in r.in.gdal by Andrey
last week that made this possible.

Paul