How many colors in Xdriver displays?

Simon Cox simon at
Tue Aug 10 18:36:45 EDT 1993

We would like to understand why so few colors are displayed
for raster maps.  We are using Grass4.1 on Sparcstations using
Solaris 1.1 (ie BSD Unix) under Openwindows3.0 etc etc and

Even when the colr table has been customized in various ways
(ramps, explicit RGB values, etc) so that it has a large
number of required colors (& categories!) it seems that
the Xdriver only finds a small number of colors to use.

(eg only a dozen colors when I am asking for 1000's defined
as ramps in one case, and similar for a custom color table with
183 values).

8-bit color means 256 different displayed values, right?
We don't get anywhere near that!  (though choosing "random colors"
does appear to show more)  colormode float does not seem to have
any effect.

Thanks for your time.

Simon Cox & Phil Schwarze

				Dr Simon Cox
         __  L				
      ,~'  L_|\            	Department of Earth Sciences       
   ,-'         \         	Monash University    
   (            \		Clayton  Vic  3168  Australia
   \    ___     /	
    L,~'   "\_x/		Phone +61 3 565 5762
              u   		Fax   +61 3 565 5062
				simon at

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