Path: utzoo!attcan!uunet!lll-winken!ames!mailrus!tut.cis.ohio-state.edu!bloom-beacon!EXPO.LCS.MIT.EDU!jim
From: jim@EXPO.LCS.MIT.EDU (Jim Fulton)
Newsgroups: comp.windows.x
Subject: Re: Beware the non-portable GX functions...
Message-ID: <8903161458.AA28597@expo.lcs.mit.edu>
Date: 16 Mar 89 14:58:10 GMT
References: <8903152321.AA00859@bird.xpiinc.uu.net>
Sender: daemon@bloom-beacon.MIT.EDU
Organization: X Consortium, MIT Laboratory for Computer Science
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I'll be even more emphatic:

People need to remember the difference between bit masks (containing boolean
values of 1 and 0) and pixmaps (containing pixel values such as WhitePixel,
BlackPixel, 42, 87, or any other number).  "Bitmap" files (such as those 
created by the bitmap program are actually bit mask files.  If you want to 
generate a depth-1 pixmap from them, you need to do something like 
XCreatePixmapFromBitmapData or XmuCreatePixmapFromBitmap.  If you blindly
assume that you can use them directly, your program will break on many, many
displays.

Anyone who assumes that BlackPixel or WhitePixel have particular values
(this includes doing boolean operations without making sure that the 
resulting values will all be well known) are dead wrong.

Hmm, maybe the sample server ought to randomly choose which values to use
for BlackPixel and WhitePixel....   :-)