From: martijn@scanner.frw.uva.nl
Brian Scamman writes:
>
> Is there a way to increase the number of greyscale levels available to the
> display window? Currently, I am able to only get six different levels. I would
> like to get 256 levels if it is possible.
>
r.colors map=mapname color=rules
will do the trick if your 'rules' file contains
0% 0 0 0
100% 256 256 256
if I'm not mistaken (I haven't tried it myself)
The issue is that in fixed mode, GRAY only gets a few slots in the
color table. If you switch to float mode: d.colormode float,
you can fill up the entire color table with gray levels.
There are problems with using float mode of course, so consider the risks.
--
Dave Gerdes
US Army Construction Engineering Research Lab
Spatial Analysis & Systems Team
dpgerdes@zorro.cecer.army.mil
(217) 352-6511 x591