Re: FVWM: Lack of free color cells, ideas

From: Eric Brandwine <eric_at_symphony.mitre.org>
Date: Fri, 22 Aug 1997 15:03:17 -0400 (EDT)

ImageMagick can take a series of images in any format, and reduce them all
to one color map. The only drawback is that it is a memory hog. I have
often run ImageMagick jobs that exceeded 200 megs. But it only has to be
done once, and the jobs are only huge if you have a lot of images. If you
decide on a standard map ahead of time, you can run the images one at a
time.

Also, as far as universal colormaps go, I think that it should be
dynamic. This is the way that Windoze (shudder) does it. When you load
an image with a large colomap, the rest of the display is fit to that map.
'Course, that requires changing the values of the pixels themselves
sometimes, so...

ericb

On Fri, 22 Aug 1997, Santeri Paavolainen wrote:

> On Fri, 22 Aug 1997, Brian Sayatovic wrote:
> > As far as sharing a single colormap, I feel your pain. I wrote a combination C
> > program and perl script to process my pixmaps to a standard colormap. I simply
> > generated a complete color spectrum to the reoslution of 128 colors, and
> > openened each pixmap, found the closest shade in the new spectrum to the one in
> > the pixmap and replaced it.
>
> As a related note, I have been thinking about hacking Xpm library a
> little, so it would handle better with small colormaps (that is 8 bit
> displays).
>
> The basic idea would be to have some value of "colormap fullness",
> which libXpm would determine before allocating a new color. It would
> then scan the current colormap and find the closest color match. Next,
> based on the "fullness" value it would either re-use the closest found
> color or choose to allocate a new cell from the colormap.
>
> The effect would be something like that as the colormap gets more and
> more crowded Xpm would accept "less close" colors than with an empty
> colormap, until at some threshold value it wouldn't allocate any new
> color cells and would re-use existing, no matter how "far" the "best"
> color match would be. (You could leave something like 64 colors not to
> be allocate by Xpm, so there would then be some cells free for random
> applications.)
>
> If you started with pre-allocated colormap portion (with xstdcmap -all)
> then Xpm would prefer to choose colors from the pre-allocated colormap
> portion before trying to allocate its own.. even better.
>
> I have not had the time to pursue the idea, so if anyone would like to
> do something similar, feel free to do so.
>
> --
> santtu_at_iki.fi I have become death, destroyer of the worlds.
>
> --
> Visit the official FVWM web page at <URL:http://www.hpc.uh.edu/fvwm/>.
> To unsubscribe from the list, send "unsubscribe fvwm" in the body of a
> message to majordomo_at_hpc.uh.edu.
> To report problems, send mail to fvwm-owner_at_hpc.uh.edu.
>

--
Visit the official FVWM web page at <URL:http://www.hpc.uh.edu/fvwm/>.
To unsubscribe from the list, send "unsubscribe fvwm" in the body of a
message to majordomo_at_hpc.uh.edu.
To report problems, send mail to fvwm-owner_at_hpc.uh.edu.
Received on Fri Aug 22 1997 - 14:04:39 BST

This archive was generated by hypermail 2.3.0 : Mon Aug 29 2016 - 19:38:00 BST