[GRASS5] A naive opinion on how grass *should* work

[Glynn Clements]

Russell Nelson wrote:

> > >  > For example the issue of adapting the region
> > >  > to displayed map (as Carl has mentioned before) would drive you crazy
> > >  > if you are doing some modeling using a larger number of maps with
> > >  > different extent and resolutions and you need to preview those maps,
> > > 
> > > Wait a second.  You mean that the region is only used for viewing??
> > 
> > No. As well as viewing, the region is also used when generating new
> > raster maps (which is probably *the* most important function of
> > GRASS).

Even more significantly, it's also used when reading existing raster
maps. With a few exceptions, input maps are resampled according to the
current region settings.

> Double aha!  Okay, so I suggest these changes:
> 
> 1) don't ask for a default region.  If a program needs one, it should
>    say "Please set the region that this program should write to using g.region".

But *most* programs need a region. The region concept is so pervasive
that it just isn't worth complicating the majority of programs to
allow for the possibility of there not being a current region. 
Especially when all that it would achieve would be to allow newbies to
defer learning about the region for a minute or two.

It might be worth making it easier to automatically create a suitable
location when importing a raster. But the main problem there is that
the data being imported is frequently uncorrelated, so the projection
and the coordinates *must* be specified by the user.

-- 
Glynn Clements <glynn.clements at virgin.net>