choosing colors for rasters

[Simon Cox]

A frequent issue when developing GRASS map databases is getting 
the colours right on raster-maps.  Although there are GRASS programs 
to manipulate these some ways, I frequently find it (ugly but) 
effective just to have a go at the MAPSET/colr/MAP file with a 
text editor!  

However, this usually requires some guesswork to set the RGB triplets 
to appear how you want them.  This would be made easier if there was 
a utility somewhere that displayed a colour-wheel/cone etc and 
allowed the user to point at a spot and be given the RGB values for 
that colour.  

Does anyone know of such a tool?  Xsomething would be best, of course. 

(I know that you can do it the other way around - specify RGB values 
and see what it shows - using the colour editor in XV, for example, 
but such an iterative approach is painful for more than 2 or 3 colours!) 
-- 
__________________________________________________
Dr Simon Cox - Australian Geodynamics Cooperative Research Centre
CSIRO Exploration & Mining,  PO Box 437,  Nedlands, WA 6009 Australia
T:  +61 9 389 8421    F:  +61 9 389 1906   simon at ned.dem.csiro.au
http://www.ned.dem.csiro.au/AGCRC/people/CoxSimon/