[GRASS5] g.pnmcomp and Gamma correction (gis.m slider?)

[Markus Neteler]

Hi,

while generating RGB composites, I came across the
problem that sometimes maps appear as too dark
(also when shading maps).

Glynn, would it be possible to add Gamma correction
to g.pnmcomp and, if so,

Michael, to have that as slider below transpacency
in gis.m?

Best

 Markus