Re: XGL and Ubuntu/Kubuntu.

From: Reid Towsley <rtowsley_at_no.spam.please>
Date: Mon May 29 2006 - 13:08:52 CST

Am I correct to assume that Xgl is similar to the composite extension? I've used the composite extension in the past, but am unsure of really what Xgl is. To get XGL to work with XFCE, I did the following:

• apt-get install xserver-xgl compiz
• In the script, removed the "gnome-window-decorator &" line and changed "startkde" to "startxfce4"
• I use wdm, and placing the xgl.desktop file in /usr/share/xsessions did not make it available when I log on, so I ran the script manually
  

I have tried both now with XFCE, and here's my results:

In XFCE, you have four sliders to adjust the compositing functions:

• shadows on windows
• transparent windows while moving
• transparent windows while resizing
• transparent menus

composite extension:

• Video overlay when watching a movie is not working. The video would not be transparent when I move the window, instead it just flickers a bunch. Also, a window cannot be seen if it is on top of the video. The video is always on top.
• Games (I tested Doom3) would be detected as a menu, so they will be transparent unless the transparent menu option is turned off. It looked kinda cool at first, but the game cannot run at full speed while it's transparent.
• Conclusion: not usable
  

XGL:

• Video overlay worked great and I was quite impressed at this point
• When running Doom3, opengl was not available and it refused to run at all
• I have the feeling that there are a lot of features of compiz that are not available to me in XFCE
  
• Conclusion: if I can get a game to run, this may be useable

Reid

Dylan Griffiths wrote:

    If you've played with Kororaa Linux's live CD, you know how nifty the eyecandy effect of Xgl is (heck, even if you've used MacOS, you know). The Dapper 6.06 is mostly setup to allow the use of Xgl, with the following notes/steps:

* You need a 3D accelerator that's supported.  nVidia seems to work fine.  ATI and Intel also work well, but there are some caveats with some Intel cards, and some ATI cards.  Make sure your 3D works before installing the Xgl package.

* You need these packages -- libgl1-mesa libglitz1 libglitz-glx1 xserver-xgl (setting this one should install the others) -- and one of -- compiz-gnome compiz-kde.

This command should do everything:
sudo apt-get install xserver-xgl compiz-gnome compiz-kde

* It's best to try the Xgl in a relatively "safe" way -- this means instead of replacing your "main" X11 server, we edit the kdm or gdm to run a shell script which runs Xgl nested inside of your regular X server.  If you have any troubles, you can just choose another session!

Here is the script I wrote (save as /usr/bin/startxgl.sh):

#!/bin/bash

#### XGL
# This starts Xgl as a nested X11 window inside regular X, in fullscreen mode.
# We then run KDE under this.  This allows us to test XGL without risking our
# regular session.

# Start Xgl server.
Xgl -fullscreen :1 -ac -accel glx:pbuffer -accel xv:pbuffer &
sleep 2
export DISPLAY=:1

# Run the eye-candy bits.
# Full set of plugins:
#gconf,miniwin,decoration,transset,wobbly,fade,minimize,cube,rotate,zoom,scale,move,resize,plac
e,switcher,trailfocus,water
LD_LIBRARY_PATH=/usr/lib/opengl/xorg-x11/lib compiz --replace decoration wobbly fade cube rotate zoom scale move resize place switcher water &
# sleep 2
gnome-window-decorator &

# KDE session here.
startkde

#### /XGL

Replace startkde with gnome-session if you're a Gnome person.

The other thing to do is add the Xgl session file to the /usr/share/xsessions directory.  The easy way to do this is run:

sudo gedit /usr/share/xsessions/xgl.desktop

and paste in
[Desktop Entry]
Encoding=UTF-8
Name=XGL
Exec=/usr/bin/startxgl.sh
Icon=
Type=Application


If you're a Gnome person, you'll now have a session (when picked from [gk]dm) which acts entirely like the Kororaa Linux.  However, if you're a KDE person like me, you'll see how the KDE version of the window manager code is not ready for prime time yet.  There are rumblings on the KDE development lists about people extending Kwin to support the compiz plugins/code natively, and rumbling from the compiz developers about supporting KDE properly.

So, for our FANCY 3D desktop we have ALMOST everything!
* 3D drivers?  Yup!
* 3D video server?  Xgl!  Extra right now, promises to be in mainline X as of Xorg 7.1.0.
* 3D window manager?  Compiz under Gnome works well, not so much under KDE.  Another year and this should be taken care of.

It's still at the "neat to look at, not useful to use" stage right now, but it's far enough along that it's easy to sit down, read a bunch of code, and do some contributing -- and get to see real changes at the end of the day!

For some reason, the Ubuntu wiki removed a version of these instructions.  Google cache has them here:
http://64.233.167.104/search?q=cache:nqx3s8P7WXAJ:https://wiki.ubuntu.com/XglHowto+howto+ubuntu+xgl+wiki&hl=en&gl=ca&ct=clnk&cd=1


Received on Mon May 29 13:08:44 2006