Subject: None
To: Izumi Tsutsui <>
From: Andrew Doran <>
List: tech-x11
Date: 03/23/2005 01:42:14
Sorry for the delay in replying. I'm on holiday at the moment.

> Hmm, but maybe generic raspos handler requires only "bit per pixel,"
> doesn't it? "The actually significant number of bits" is provided
> by info of each color in other members, I think.

I was thinking of the TC mfb, which is mono but uses byte addressing.
Only the lowest bit is significant (so depth of 1 and bpp of 8). Are
there other devices like that?

> > - a flag to indicate whether the frame buffer is simple and can be
> > handled by mfb/cfb or is something a bit different, like a VGA or
> > PixelStamp?
> I think such device specific features could be determined by

It may not be possible to drive certain types of display with the
usual code (as is the case with the PixelStamp, no direct FB access).
Rather than teaching the X server about each of the black sheep, why
not have a flag passed down by the kernel?

> > - a flag to indicate whether or not colormap changes are accepted?
> >   Not entirely necessary, but nice to have.
> Can't we check it by a return value of WSDISPLAYIO_GETCMAP or

I agree with your suggestion here.