Re: tlug: X black and white

[Alberto Tomita <atomita@example.com>]

> Yes.  If you are talking about X images (as opposed to pixmaps), image
> handling is highly implementation-dependent.  You have to be extremely
> careful to do proper conversions.

well, there are pixmaps and there are pixmaps...

> One would think that the Xlib routines would handle this properly in
> communications with the server.  Is this considered a bug?  I would.

"it's not a bug, it's a feature" 

Quoting the FAQ:

   Q.D3- wrong colors or black and white images in 24bpp modes for Netscape,
         xanim, WABI and others

   This is a long-standing problem with all those client programs. It is
   NOT a problem in XFree86.

   Technical details: it is caused by a relatively new feature of XFree86
   (24bpp modes with 24bpp pixmaps) that is very poorly understood by
   many client authors: they assume 32bpp pixmaps instead of asking the
   XFree86 server for those details. Others (like Netscape) do ask for
   the pixmap size, but since they don't support 24bpp pixmaps, they fall
   back to using 1bpp (monochrome) pixmaps...

   The current public versions of XFree86 can only support a 1:1 mapping
   between the framebuffer depth and the pixmap depth. Some commercial
   Xservers support 32bpp pixmaps in 24bpp modes, and hence they present
   an interface to client programs that happens to match their
   assumptions. XFree86 4.0 will also support this feature.

   There are two possible solutions to this right now:
     * do not use 24bpp modes, but rather 16bpp or 32 bpp modes. 32bpp is
       best, but it requires more video memory than 24bpp.

     * don't use broken X clients. There are patches for Netscape and
       even compiled binaries on the net that fix this bug.

On the other hand, if "it is not a problem", why "...fix this bug"? :)
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