[GRASS5] [bug #1232] (grass) r.out.ppm3 improperly registers

[Glynn Clements]

Request Tracker wrote:

> Subject: r.out.ppm3 improperly registers 
> 
> Platform: GNU/Linux/i386
> grass obtained from: Mirror of Trento site
> grass binary for platform: Compiled from Sources
> GRASS Version: 5.0pre5
> 
> Using the r.out.ppm3 option impropery registers. I attempted to
> reimport the ppm image, without changing region parameters, and get:
> 
> WARNING: G_set_window(): Illegal latitude for North
> ERROR: region for current mapset is invalid
>        line 3: <north: 1866N>
>        run "g.region"
> 
> Of course, a latitude 1866N is not proper. The original rgb rasters
> display properly, and running r.info, find that they have lat/lon's
> that are reasonable.

Note that the problem is with r.in.ppm, not r.out.ppm3. The PPM file
is unregistered. r.in.ppm (in fact, most r.in.* commands) set the
region to [0,0,width,height] prior to importing; clearly, this doesn't
work for lat-lon regions (unless the image is smaller than 180x90
pixels).

I started looking into this after Eric (IIRC) fixed r.in.tiff. I
didn't entirely understand the consequences of Eric's chosen fix (set
the projection to X-Y while importing), so I started looking deeper.
Then I got sidetracked, and forgot all about it :( .

It may be possible (although messy) to work around the problem
by switching projections manually.

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