[GRASS-dev] g.proj to create a new location

GRASS GRASS developer
1

On Mon, February 12, 2007 19:28, Michael Barton wrote:

I'm continuing to follow this discussion and I don't think it will be a

huge

problem to wrap this into TclTk. The simplest way for TclTk to parse

this is

to simply have each datum transformation be a separate line in text sent to
stdout.

1:dt1 parameters
2:dt2 parameters
3:dt3 parameters
...and so on

The way I'm thinking of doing this is to open a read channel from the

command as follows...

set input [open "|g.proj epsg=$epsgcode epsgloc=$epsgloc datumtrans=-1"]

set dtrans [read $input]

close $input
if {$dtrans==""} {
    # I assume that $dtrans=="" if there is only one default parameter

open "|g.proj epsg=$epsgcode epsgloc=$epsgloc datumtrans=0"

This means that if there is only one set of default parameters, these are
not set explicitely in PROJ_INFO. Another option would be to make this

open "|g.proj epsg=$epsgcode epsgloc=$epsgloc datumtrans=1"

to do so.

I don't know what is better. If we want to leave the choice to the user,
the GUI could offer it (maybe in form of a checkbox), or should this be
only for powerusers, and GUI users live with the default=no parameters
solution ?

Moritz