ATI rage 128 on the TiBook 400, alternative resolutions

[Antony Lesuisse <antony@lesuisse.com>]

I own a TiBook 1st generation, G4 400Mhz, rage 128 8Mo RAM, LCD
resolution of 1152x768, and i only have Debian installed. 

I'm using:
    - XFree86 version: 4.2.1.1.
    - Kernel 2.4.20-ben1. r128 module.
    - resolution of 1152x768x16
And everything works well. Xv works and OpenGL windows are accelerated.

I know that with the same hardware under MacOS 9, you have to possiblity
to change the resolution of the screen to 640x480, 800x600, 1024x768.
When you choose a resolution smaller than the physical LCD, the
framebuffer is automatically scaled fullscreen and anti-aliased.

I notice that when you use Xv extension to display YUV framebuffers, you
may scale it fullscreen using hardware (mplayer does it). But when SDL
applications enable the fullscreen mode they stay in the center of the
screen.

Is it possible to
    - start the X server in an alternative resolution on the LCD, having
      it scaled or not ?
    - having the SDL_FULLSCREEN flag working ?

My aim is to play 3D accelerated OpenGL apps in 800x600 or 640x480
resolution in fullscreen mode. (I don't care about the vga output.)

I currently use the folowing modeline for the LCD 1152x768x16:
Modeline "1152x768" 78.741 1152 1173 1269 1440  768 769 772 800 +HSync +VSync

I would like to thank the people who took care of the various tibook
drivers, especially Michel Daenzer and Benjamin Herrenschmidt, allowing
us to run smoothly Debian on this great hardware.

-- 
Antony Lesuisse
GPG EA2CCD66: 4B7F 6061 3DF5 F07A ACFF  F127 6487 54F7 EA2C CD66