[GRASS-user] Probably a stupid question: r.mapcalc display colours

[Glynn Clements]

Moritz Lennert wrote:

> > I'm using r.mapcalc to clip white areas out of some rasters.
> >
> > The clipping works fine, but the new map displays in different colours
> > to the old map, even though the pixels have the same values as the old
> > map. Why is this?
> 
> r.mapcalc probably just assigns the default color table.

Except for one specific case[1], r.mapcalc doesn't assign any colour
table. The library (libgis in 6.x, libraster in 7.0) provides a
default colour table (rainbow) for any map which lacks one.

[1] The specific case is for an expression of the form
"newmap = oldmap", in which case it will copy the colour table and
categories.

-- 
Glynn Clements <glynn at gclements.plus.com>