Jan?10??95?03?49?49?pm@bnr.ca>
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A problem was recently brought to my attention regarding the use of multiple
X display monitors in GRASS. When using two or more X display monitors,
the monitors started after the first one appear normal until an image is
displayed, at which time the monitor(s) fade to a dull grey and by default
erases to a dull grey. Images subsequently displayed also appear to have a h
ighly muted colortable. This even happens when the colormode is set to float.
Has anyone encoutered this problem and/or developed a solution? Any help
would be appreciated.
Mark Gibb
USACERL
Yes, I and many others have had this problem and reported it to the grassu
and grassp lists. I have never seen any reply that offered a solution (at
least not in the past 3 years). I'm sure many Grass users would appreciate
you working on a solution...
Martijn van Leusen
My two cents worth. The problem is essentially unsolvable, given that
individual display monitors do not share color in an X colormap sense.
The first monitor allocates x amount of sharable color cells from the X
colormap, and the second tries to allocate the same color cells, but is left
with something less because an individual color requested by Grass is not
always returned by X.
One solution is to create a colormap specific to Grass monitors. A high-end
display can usually share colormaps, so Grass could create a colormap with the
colors it needs, and share it between Grass monitors.
However, most low to medium-end monitors allow only one colormap to be used at
any one time, and I think Grass makes this assumption in its coloring scheme.
Creating a new colormap for Grass would work for Grass monitors, but this
would throw off the coloring scheme for the rest of your display. I haven't
been around Grass too long, but maybe this was done in a previous version?
Randy Hills, National Operational Hydrologic Remote Sensing Center (NOHRSC)
National Weather Service
Minneapolis, MN