24-bit monitor and grass

[BAKERWL]

It looks to me that the GRASS XDRIVER source code (in
src/display/devices/XDRIVER/XDRIVER) sets the Visual to whatever the
default is for the hardware.  On a machine with an 8-bit display
that should be the X PseudoColor Visual.  On a 24-bit display that
I would guess would be the X DirectColor Visual.  PseudoColor gives
a possible 256 colors, while DirectColor gives about 16 million.

The default Visual is requested by the XDRIVER in Graph_Set.c routine
GetRealNumberOfColors().

I'm no X-programmer, but it seems to me that since the XDRIVER does
not automatically set the X Visual to Pseudocolor, the XDRIVER should
take advantage of 24-bit color if the machine has it...

	Bill Baker
	bakerwl at corral.uwyo.edu