[203] in Zephyr Mailing List
Re: zwgc display problem on color suns
daemon@ATHENA.MIT.EDU (Chuck Silvers)
Tue Jan 23 13:16:26 1996
From: Chuck Silvers <chs@catapent.com>
To: "Derrick J. Brashear" <shadow@dementia.org>
Cc: zephyr@MIT.EDU
In-Reply-To: Your message of "Tue, 23 Jan 1996 12:21:37 EST."
<ML-1.3.2.822417697.1943.shadow@johnstown.andrew.cmu.edu>
Date: Tue, 23 Jan 1996 10:11:31 -0800
In message <ML-1.3.2.822417697.1943.shadow@johnstown.andrew.cmu.edu>, "Derrick
J. Brashear" writes:
> Hi,
>
> We've noticed a problem on our Suns with cg6 display adapters where
> when selecting text in zwgc, some of the selected text will not be properly
> displayed. However, if you drag slowly across a line, left to right, then dra
> g
> slowly down over all the lines, everything is fine.
>
> The previous Zephyr maintainer here came up with a hack which fixes the
> problem,
> but causes a bit of flicker when you're selecting text in a zephyr.
>
> Has anyone else investigated/solved this problem?
>
> Thanks
> -D
Yea, it's a bug in the cg6 support in the MIT X server,
particularly in sunGXPolyTEGlyphBlt() and sunGXTEGlyphBlt().
You can work around it by running the X server with "-noGX",
or building an X server that uses miPolyGlyphBlt and miImageGlyphBlt
instead of the sunGX* routines. Clearly this doesn't fix the actual
problem, but the routines in question looked ok to me. I have a
simple program which triggers the bug too, but I won't include that here
since this is already far off topic.
-Chuck
