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From: envbvs@epb2.lbl.gov (Brian V. Smith)
Newsgroups: comp.windows.x
Subject: Re:  GXxor problems on Xqvss
Message-ID: <8021@dog.ee.lbl.gov>
Date: 10 Nov 90 00:56:57 GMT
References: <9011091619.AA28709@Larry.McRCIM.McGill.EDU>
Sender: usenet@dog.ee.lbl.gov
Reply-To: envbvs@epb2.lbl.gov (Brian V. Smith)
Organization: lbl
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X-Local-Date: Fri, 9 Nov 90 16:56:57 PST

In article <9011091619.AA28709@Larry.McRCIM.McGill.EDU>,
mouse@LARRY.MCRCIM.MCGILL.EDU writes:
|> > Some X programs (that use special GC's like xor) do not display
|> > correct on my Xqvss server.  When I change display to a Xsun server
|> > on a SPARC (also form the mit tape) but the client is still running
|> > on the same, original host, the programs display fine.
|> 
|> This could be the common XOR mistake.  Is the qvss a color server and
|> the SPARC a monochrome?  If so, the problem is probably programmers not
|> thinking about how GXxor works and carelessly drawing with the
|> foreground (or sometimes the background) color and function GXxor,
|> which will work correctly only when the background (resp. foreground)
|> color is 0.  On a monochrome display, this is true often enough that
|> the bug goes unnoticed, but it shows up big-time on color machines.
|> 

Sorry to rain on your solution, but the qvss is a monochrome server.
The qdss is color.  Both of these are for Vaxstations.
I personally have never seen any problems with XOR on our 4 qvss machines.

--
Brian V. Smith    (bvsmith@lbl.gov)
Lawrence Berkeley Laboratory
I don't speak for LBL; they don't pay me enough for that.