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

GRASS GIS GRASS GIS developer
,
1

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.

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.

Find in GRASS 5.7 CVS or in the weekly generated Linux
binary snapshot.

Cheers

Markus Neteler
Andrea Antonello

PS: Note for Italian users: The entries in the PROJ4 version
    of epsg codes is wrong. Both fuso est and fuso ovest have
    different values, no idea why this doesn't get fixed:
    http://bugzilla.remotesensing.org/show_bug.cgi?id=510
    (maybe you add yourself to CC to raise the interest)
    Related:
    http://bugzilla.remotesensing.org/show_bug.cgi?id=367

2

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. :slight_smile: )

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

3

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. :slight_smile: )

... we stay tuned :slight_smile:

> 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

4

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

d.zoom
:slight_smile: