Jordan Crouse jordan.crouse at
Wed Apr 18 11:47:50 EDT 2007

On 18/04/07 17:27 +0200, Bert Freudenberg wrote:
> On Apr 18, 2007, at 17:00 , Jordan Crouse wrote:
> >On 18/04/07 12:36 +0200, Bert Freudenberg wrote:
> >>Another option that has been discussed is rendering at lower
> >>resolution and using the Geode's video scaler, which supposedly can
> >>do arbitrary scaling of RGB565 (see p. 388 of the LX data book). I'm
> >>not sure if this is exposed in X11, though, or if this is even
> >>feasible to use for a frame buffer (it reads like it might be for
> >>external video sources only).
> >
> >Please, stop perpetrating this myth.  The LX can not scale  
> >arbitrary chunks
> >of pixels - it can only upscale and downscale the entire visible  
> >area.  This
> >is available to X through some clever RandR tweaking.
> Err - which myth are you referring to? If we could upscale the whole  
> screen (effectively lowering the framebuffer size) we'd be happy  
> campers I guess? Note this is not only interesting for 3D but for any  
> kind of full-screen animation.

The myth is that this is some sort of arbitrary thing that you can make
cleanly happen to different parts of the screen.  This is a mode change,
with all the usual flickering and noise that accompany any
mode change.  Do a ctrl-alt-f1 switch to a fb console on a B2 - thats what
you will experience when you change the mode with RandR.


Jordan Crouse
Senior Linux Engineer
Advanced Micro Devices, Inc.

More information about the Devel mailing list