Compiz
| Summary |
|---|
| Compiz Configuration |
| Xcompmgr |
| Cairo Compmgr |
Compiz is a compositing window manager. It cannot be used simultaneously with other window managers such as Openbox, Fluxbox, or Enlightenment. Users who want to keep their current window managers and add some effects to it may wish to try Xcompmgr instead.
Requirements
Users of major DEs can make good use of compiz-manager, performing brief requirements checking and switching to fallback WM in case of errors.
Installation
Install packages, available in AUR.
Initial configuration
While the appearance of the windows and their contents is a function of GTK+ and Qt, the frames around the windows are controlled by the Window Decoration plugin. To use it make sure you have a window decorator installed. Depending on what packages you have downloaded you can choose among several window decorators. The most common ones are Emerald, kde-window-decorator, and gtk-window-decorator. The emerald decorator has the advantage that it fits better to Compiz's screen handling and offers transparency effects. To set your default window decorator type the following command string in the "Window Decoration" plugin's settings under the field "Command".
Ensure that the "Window decorator" plugin is enabled in CCSM's "effects" tab, the "command" field is filled in to start a decorator.
To set emerald as your default window decorator type:
$ emerald --replace
To set the kde-window-decorator as an alternative to Emerald type:
$ kde4-window-decorator --replace
To set the compiz-decorator-gtk as an alternative to Emerald type:
$ gtk-window-decorator --replace
Additional software
Decorators
- Emerald — Compiz's own window decorator with few dependencies.
- compiz-decorator-gtk, compiz-decorator-kde — Alternatives to Emerald, using your desktop environment's configuration backends and looks.
Other
- ccsm (CompizConfig settings manager) - GUI application that lets you configure all of Compiz's plugins
- fusion-icon - offers a tray icon and a nice way to start Compiz, start CCSM and change the Window Manager/Decorator
Starting Compiz Fusion
Manually (with "fusion-icon")
Launch the Compiz Fusion tray icon:
$ fusion-icon
See General Troubleshooting#Session permissions if you get some permission related errors.
Right click on the icon in the panel and go to 'select window manager'. Choose "Compiz" if it isn't selected already, and you should be set.
If this fails you can start Compiz Fusion by using the following additional command to replace your default window decorator with Compiz's window decorator (Emerald):
$ emerald --replace
Again, note: If you want to use Compiz window decorations make sure you have the "Window Decoration" plugin marked in the Compiz settings through CCSM.
Manually (without "fusion-icon")
Launch Compiz with the following command (which replaces your current window manager):
$ compiz --replace ccp &
A quick overview over common Compiz command-line options:
-
--indirect-rendering: use indirect-rendering (AIGLX) -
--loose-binding: can help performance issues (NVIDIA?) -
--replace: replace current window-manager -
--keep-window-hints: keep the gnome window manager gconf-settings for available viewports -
--sm-disable: disable session-management -
ccp: the "ccp" command loads the last configured settings from CCSM (CompizConfig Settings Manager) otherwise Compiz will load with no settings and you won't be able to do anything with your windows like dragging, maximizing/minimizing, or moving.
KDE4
Use System Settings (easiest)
Go to: System Settings > Default Applications > Window Manager > Use a different window manager
If you need to run Compiz with custom options select "Compiz custom", then create the following script:
/usr/local/bin/compiz-kde-launcher
#!/bin/bash LIBGL_ALWAYS_INDIRECT=1 compiz --replace ccp & wait
Then make it executable:
$ chmod +x /usr/bin/compiz-kde-launcher
When running fusion-icon from a terminal you can see the command line with which Compiz was started.
Autostart with "fusion-icon"
Add a symbolic link, that points to fusion-icon, in your KDE Autostart directory:
$ ln -s /usr/bin/fusion-icon ~/.kde4/Autostart/fusion-icon
Next time KDE is started, it will load fusion-icon automatically.
Autostart link without "fusion-icon"
- Append a desktop entry in the KDE Autostart directory. If it doesn't exist already (it should), create it:
~/.kde4/Autostart/compiz.desktop
[Desktop Entry] Type=Application Encoding=UTF-8 Name=Compiz Exec=/usr/bin/compiz ccp --replace NoDisplay=true # name of loadable control center module X-GNOME-WMSettingsModule=compiz # autostart phase X-GNOME-Autostart-Phase=WindowManager X-GNOME-Provides=windowmanager # name we put on the WM spec check window X-GNOME-WMName=Compiz # back compat only X-GnomeWMSettingsLibrary=compiz
- If you want to use the optional Fusion Icon application, launch
fusion-icon. If you log out normally with Fusion Icon running, KDE should restore your session and launch it the next time you log in, if you have the following enabled (also available in System Settings > Startup and Shutdown > Session Management > Restore previous session):
~/.kde4/share/config/ksmserverrc
[General] [...] loginMode=restorePreviousLogout [...]
Export KDEWM without "fusion-icon" (preferred)
As root you must create a short script by doing the following in your terminal. This will allow you to load Compiz with the switches because doing it directly via $ export KDEWM="compiz --replace ccp --sm-disable" doesn't seem to work:
$ echo "compiz --replace ccp --sm-disable &" > /usr/bin/compiz-fusion
Ensure that /usr/bin/compiz-fusion has executable (+x) permissions.
$ chmod +x /usr/bin/compiz-fusion
Choose one of the following:
1) For your user only:
~/.kde4/env/compiz.sh
KDEWM="compiz-fusion"
2) System-wide:
/etc/kde/env/compiz.sh
KDEWM="compiz-fusion"
GNOME
If you have installed GNOME3 with gnome-shell, either enable forced Fallback mode (System Info > Graphics) or simply uninstall gnome-shell.
Alternate Session for GNOME (preferred method for experienced Compiz/Dock users)
The gnome-session-compiz can be used to add an additional menu entry in the GNOME session login dialog. This method does not require foced fallback mode and/or modifications to sensitive system files/settings. Also, you can switch between GNOME Shell and Compiz/Cairo Dock between sessions. If you can't get it working, you can always go back to your original GNOME session.
For this method to work, Compiz and Cairo Dock (Taskbar/Panel) may have to be configured initially for fresh accounts, from another working session (CCSM in GNOME Shell should work fine).
This method completely replaces the GNOME's window manager and panel (they are not launched at all, rather than being replaced or killed later). So, before actually switching to this alternate session, you may want to configure corresponding/alternate features of the original panel application in Cairo Dock:
- Add Application Menu icon to Cairo Dock and remember its key-bindings.
- Remap Application Menu key-bindings to
ALT+F1andALT+F2, for convenience. - Add Clock, WiFi, NetSpeed icons to the dock as applicable.
- Add Log-out icon:
- Set the command for logout to
gnome-session-quit --logout - Set the command for shutdown to
gnome-session-quit --power-off
- Set the command for logout to
- Add the Notification Area Old (systray) icon to Cairo Dock.
Autostart (without "fusion-icon") (preferred method)
This Method makes use of the Desktop Entry Specification to specify a Compiz Desktop Entry and of the GConf default windowmanager setting. Thanks to the Desktop Entry you should be able to select Compiz as a windowmanager out of GDM.
1) If the following file doesn't already exist (it should), create it
/usr/share/applications/compiz.desktop
[Desktop Entry] Type=Application Encoding=UTF-8 Name=Compiz Exec=/usr/bin/compiz ccp #Make sure ccp is included so that Compiz loads your previous settings. NoDisplay=true # name of loadable control center module X-GNOME-WMSettingsModule=compiz # autostart phase ##-> the following line cause gnome-session warning and slow startup, so try not to enable this # X-GNOME-Autostart-Phase=WindowManager X-GNOME-Provides=windowmanager # name we put on the WM spec check window X-GNOME-WMName=Compiz # back compat only X-GnomeWMSettingsLibrary=compiz
If the above doesn't work (in most cases it does), for example if you notice some issues with windows refreshing or low performance, try:
Exec=/usr/bin/compiz ccp --indirect-rendering
or:
Exec=/usr/bin/compiz --replace --sm-disable --ignore-desktop-hints ccp --indirect-rendering:
Instead of:
Exec=/usr/bin/compiz ccp
Some Users noticed a "lag" of 4-10 seconds when loging in from a login manager. The solution is to change the command to:
Exec=bash -c 'compiz ccp decoration --sm-client-id $DESKTOP_AUTOSTART_ID'
as noted in the forum. You can also add the extra parameters as described above if needed.
2) Set some GConf parameters using the gconftool-2 command in a terminal window or do it visually with Configuration Editor (gconf-editor). The following outlines using the command line method, but you can also see which keys to change using gconf-editor:
gconftool-2 --set -t string /desktop/gnome/session/required_components/windowmanager compiz
Autostart (without "fusion-icon") (with GNOME fallback mode session)
Do the following
/usr/share/gnome-session/sessions/gnome-fallback.session
RequiredComponents=compiz;gnome-settings-daemon; RequiredProviders=windowmanager;notifications; DefaultProvider-windowmanager=compiz DefaultProvider-notifications=notification-daemon
Autostart (with "fusion-icon")
To start Compiz Fusion automatically when starting a session go to System > Preferences > Startup Applications. In the Startup Programs tab, click the Add button.
You will now see the Add Startup Program dialogue. Fill it in as follows.
Name:
Compiz Fusion
Command:
fusion-icon
Comment: (Put anything you like or leave blank.)
When you're done hit the Add button. You should now see your startup program in the list in the Startup Programs tab. It must be checked to be enabled. You can uncheck it to disable Compiz on startup and switch back to Metacity.
You may also need to use the gconftool-2 command in a terminal window to set the following parameter, otherwise Fusion Icon might not load the windows decorator.
$ gconftool-2 --type bool --set /apps/metacity/general/compositing_manager false
Mate desktop
Autostart (without "fusion-icon") (preferred method)
As with Gnome, create a compiz.desktop file (see Compiz#Autostart_.28without_.22fusion-icon.22.29_.28Preferred_Method.29), then set Compiz as the default window manager :
- on Mate 1.6 and higher, edit the following gsettings value
$ gsettings set org.mate.session.required-components windowmanager compiz
Xfce
Xfce autostart (without "fusion-icon")
This method will start Compiz directly through the Xfce session manager without loading Xfwm.
Please note the change to .xml config files in Xfce newer than 4.2.
To install the session manager, install xfce4-session.
Now we have to configure the default/failsafe session of Xfce
Edit the ~/.config/xfce4/xfconf/xfce-perchannel-xml/xfce4-session.xml or (to make the change for all Xfce users) /etc/xdg/xfce4/xfconf/xfce-perchannel-xml/xfce4-session.xml:
Replace the xfwm startup command,
<property name="Client0_Command" type="array"> <value type="string" value="xfwm4"/> </property>
with the following:
<property name="Client0_Command" type="array"> <value type="string" value="compiz"/> <value type="string" value="ccp"/> </property>
To prevent the default session from being overwritten you may also add this:
<property name="general" type="empty"> ... ... <property name="SaveOnExit" type="bool" value="false"/> </property>
To remove the existing sessions:
$ rm -r ~/.cache/sessions
Xfce autostart (with "fusion-icon")
Method 1
This will load Xfwm first then replace it with Compiz.
Open Xfce Settings Manager > Sessions & Startup > Application Autostart:
(Name:) Compiz Fusion
(Command:) fusion-icon
Method 2
Edit the file ~/.config/xfce4-session/xfce4-session.rc (settings in this file is used in preference).
Or to make the change for all Xfce users:
/etc/xdg/xfce4-session/xfce4-session.rc
[...] [Failsafe Session] Client0_Command=fusion-icon
This will cause xfce to load Compiz instead of Xfwm when the user has no existing sessions.
To prevent the default session from being overwritten you may also add:
/etc/xdg/xfce4-session/xfce4-session.rc
[General] AutoSave=false SaveOnExit=false
To remove the existing sessions
$ rm -r ~/.cache/sessions/
Method 3
Check if this file exists:
~/.config/xfce4/xfconf/xfce-perchannel-xml/xfce4-session.xml
If not, do:
cp /etc/xdg/xfce4/xfconf/xfce-perchannel-xml/xfce4-session.xml ~/.config/xfce4/xfconf/xfce-perchannel-xml/xfce4-session.xml
Then edit ~/.config/xfce4/xfconf/xfce-perchannel-xml/xfce4-session.xml.
or (to make the changes for all xfce4 users) /etc/xdg/xfce4/xfconf/xfce-perchannel-xml/xfce4-session.xml:
Edit Client0_Command to look like:
<property name="Client0_Command" type="array">
<value type="string" value="fusion-icon"/>
<value type="string" value="--force-compiz"/>
</property>
If --force-compiz doesn't work use compiz --replace --sm-disable --ignore-desktop-hints ccp instead.
Add the SaveOnExit property, if missing and set it to false:
<property name="general" type="empty"> <property name="FailsafeSessionName" type="string" value="Failsafe"/> <property name="SessionName" type="string" value="Default"/> <property name="SaveOnExit" type="bool" value="false"/> </property>
finally remove old xfce4 sessions:
$ rm -r ~/.cache/sessions/
Now xfce4 will load Compiz instead of Xfwm.
As a standalone window manager
The package compiz-core by itself is sufficient to start using Compiz Fusion. However ccsm and emerald (or another window decorator) are additional highly recommended packages. fusion-icon, compiz-fusion-plugins-main and compiz-fusion-plugins-extra are also available.
To autostart Compiz Fusion configure .xinitrc to launch Compiz as:
~/.xinitrc
exec compiz ccp
You can also add other command-line options to your .xinitrc.
Or if using fusion-icon:
~/.xinitrc
exec fusion-icon
However chances are you will need additional apps (e.g a panel) for optimal usability:
~/.xinitrc
tint2 & cairo-dock & exec fusion-icon
To add a root menu similar to that in Openbox, Fluxbox, Blackbox etc. you must install the package compiz-deskmenu. Upon a restart of Compiz Fusion, you should be able to middle click on your desktop to launch the menu.
If it does not automatically work, enter the CompizConfig Settings Manager, and in Commands tab, within the General Settings menu, ensure that there is a command to launch Compiz-Deskmenu, and the appropriate key binding is set to Ctrl+Space.
If it still does not work, enter the Viewport Switcher menu, and change "Plugin for initiate action" to 'commands', and "Action name for initiate" to run_command0_key.
An alternative is to use mygtkmenu, also in AUR.
Allow users to shutdown/reboot
Refer to this wiki page. If using "The Modern way" of policykit you can add the command to CCSM > General > Commands and assign a short-cut key to it or alternatively you can use a launcher application.
Miscellaneous
Configuration
You must do this so your windows function like you expect them to!.
Using gtk-window-decorator
In order to use gtk-window-decorator, install the package compiz-decorator-gtk and select "GTK Window Decorator" instead of "Emerald" as your window decorator in Fusion Icon or whatever other program you are using to configure compiz.
gconf: additional Compiz configurations
To achieve more satisfying results from Compiz, you can tweak its config with gconf-editor:
$ gconf-editor
Note that now compiz-core isn't built with gconf support; It is now built with gconf support through compiz-decorator-gtk. So, you need to install it if you want to use gconf-editor to edit your Compiz configuration.
The Compiz gconf configuration is located in in the key apps > compiz > general > allscreens > options.
"Active plugins" is where you specify the plugins you would like to use. Simply edit the key and add a value(refer to the key apps > compiz > plugins to see possible values). Plugins I’ve found useful are screenshot, png, fade, and minimize. Please do not remove those enabled by default.
ATI R600/R700 notes
While using Fusion Icon you shouldn't experience any problems because it takes care of everything for you, but if you are using one of the autostart methods that do not involve Fusion Icon you will run into trouble. For example when using the Xfce autostart method without fusion icon you must edit ~/.config/xfce4/xfconf/xfce-perchannel-xml/xfce4-session.xml per the instructions above. However, if you follow the directions above explicity you will find that Compiz does not load. You must instead make your xfce4-session.xml file look like this
<property name="Client0_Command" type="array"> <value type="string" value="LIBGL_ALWAYS_INDIRECT=1"/> <value type="string" value="compiz"/> <value type="string" value="--sm-disable"/> <value type="string" value="--ignore-desktop-hints"/> <value type="string" value="ccp"/> <value type="string" value="--indirect-rendering"/> </property>
This example targeted Xfce specifically, but it can be adapted to any desktop environment. It's just a matter of figuring out how to add it to the proper config file. The key thing is the required command which if typed on a command line would look like this
LIBGL_ALWAYS_INDIRECT=1 compiz --sm-disable --ignore-desktop-hints ccp --indirect-rendering
This is how Xfce's session manager interprets the above XML code. Notice that you do not need --replace because you are not first loading Xfwm and then Compiz.
Tips and tricks
Fallback
If you are using KDE, GNOME or Xfce and something is not right, for example you don’t see borders for your window, you can switch back to default DE window manager with this command:
wm_name --replace
with kwin, metacity or xfwm4 instead of wm_name.
Keyboard shortcuts
Default plugin keyboard shortcuts (plugins have to be activated!)
- Switch windows =
Alt+Tab. - Switch to next desktops =
Ctrl+Alt+←. - Switch to previous desktop =
Ctrl+Alt+→. - Move window =
Alt+Left click. - Resize window =
Alt+Right click.
A more detailed list can be found under CommonKeyboardShortcuts in the Compiz wiki or you can always just look at your plugin's configuration.
Troubleshooting
Missing GLX_EXT_texture_from_pixmaps
On ATI cards (first solution)
https://bbs.archlinux.org/viewtopic.php?id=50073 If you run into the following error when trying to run Compiz Fusion on an ATI card:
Missing GLX_EXT_texture_from_pixmap
This is because Compiz Fusion's binary was compiled against Mesa's OpenGL library rather than ATI's OpenGL library (which is what you are using).
copy the library into a directory to keep it because ATI's drivers will over write it.
$ install -Dm644 /usr/lib/libGL.so.1.2 /usr/lib/mesa/libGL.so.1.2
Once you have it copied, you can reinstall your fglrx drivers. Now you can start Compiz Fusion using the following example syntax:
LD_PRELOAD=/usr/lib/mesa/libGL.so.1.2 compiz --replace &
On ATI cards (second solution)
An other problem could arise with GLX_EXT_texture_from_pixmap, it is possible that the card could only render it indirectly, then you have to pass the option to your libgl like that:
LIBGL_ALWAYS_INDIRECT=1 compiz --replace ccp &
(Workaround tested on the following card : ATI Technologies Inc Radeon R250 [Mobility FireGL 9000] (rev 02))
On Intel chips
First off, check that you're using the intel driver as opposed to i810. Then, run the following command to run Compiz (must use this every time.).
LIBGL_ALWAYS_INDIRECT=true compiz --replace --sm-disable ccp &
If you then do not have borders, run:
emerald --replace
As at 17-Oct-07 the Compiz-Fusion Wiki states: "If you are using an Intel GMA card with AIGLX, you will need to start Compiz Fusion with LIBGL_ALWAYS_INDIRECT=1 appended."
Compiz starts, but no effects are visible
If you have installed compiz-decorator-gtk:
Check if GConf schema was correctly installed:
$ gconftool-2 -R /apps/compiz/plugins | grep plugins
make sure that all plugins are listed (not only fade!). If not, try to install Compiz schema manually (do this as normal user, not as root!!!):
$ gconftool-2 --install-schema-file=/usr/share/gconf/schemas/compiz-decorator-gtk.schemas
Compiz starts, but gtk-window-decorator does not
It is a configuration problem for gconf and gconfd. You may try removing ~/.gconf/. This will erase your Compiz settings, so be sure to reconfigure.
Finally as user:
$ gconftool-2 --install-schema-file=/usr/share/gconf/schemas/compiz-decorator-gtk.schemas
Compiz appears to start, but there are no window borders
When running Fusion Icon from terminal, you get output like this:
$ fusion-icon
* Detected Session: gnome * Searching for installed applications... * NVIDIA on Xorg detected, exporting: __GL_YIELD=NOTHING * Using the GTK Interface * Metacity is already running * Setting window manager to Compiz ... executing: compiz --replace --sm-disable --ignore-desktop-hints ccp compiz (core) - Warn: No GLXFBConfig for depth 32 compiz (core) - Warn: No GLXFBConfig for depth 32 compiz (core) - Warn: No GLXFBConfig for depth 32 compiz (core) - Warn: No GLXFBConfig for depth 32 compiz (core) - Warn: No GLXFBConfig for depth 32 compiz (core) - Warn: No GLXFBConfig for depth 32
You may also try adding Option "AddARGBGLXVisuals" "True" and Option "DisableGLXRootClipping" "True" to your "Screen" section, if you are using the NVIDIA binary driver. If you used any other Options elsewhere in /etc/X11/xorg.conf.d/ to get Compiz working and still have no luck, try commenting them out and using only the aformentioned ARGBGLXVisuals and GLXRootClipping Options.
With gconf-editor you can easly enable "Window decoration", "Move" and "Resize" plugins.
$ gconf-editor
Navigate to apps > compiz > general > allscreens > options.
Add/Edit "active_plugins" Key (Name: active_plugins, Type: List, List type: String).
Add "decoration", "move", and "resize" to the list.
Another way to fix this:
- Launch
ccsm. - Find Window Decoration and make sure it is enabled.
- Now click on it, to edit the options.
- If the entry behind command is empty, use
gtk-window-decoratororkde-window-decoratororemerald. - Close CCSM and the borders should now appear.
Compiz starts and borders appear, but windows won't move
Be sure you have the "Move Window" plugin installed and enabled in the CompizConfig Settings Manager.
Blank screen on resume from suspend-to-ram using the NVIDIA binary drivers
If you receive a blank screen with a responsive cursor upon resume, try disabling sync to vblank:
$ gconftool -s /apps/compiz/general/screen0/options/sync_to_vblank-t boolean false
Fusion Icon doesn't start
If you get an output like this from the command line:
$ fusion-icon
* Detected Session: gnome
* Searching for installed applications...
Traceback (most recent call last):
File "/usr/bin/fusion-icon", line 57, in <module>
from FusionIcon.interface import choose_interface
File "/usr/lib/python2.5/site-packages/FusionIcon/interface.py", line 23, in <module>
import start
File "/usr/lib/python2.5/site-packages/FusionIcon/start.py", line 36, in <module>
config.check()
File "/usr/lib/python2.5/site-packages/FusionIcon/util.py", line 362, in check
os.makedirs(self.config_folder)
File "/usr/lib/python2.5/os.py", line 172, in makedirs
mkdir(name, mode)
OSError: [Errno 13] Permission denied: '/home/andy/.config/compiz'
the problem is with the permission on ~/.config/compiz/. To fix it, use:
# chown -R <username> /home/<username>/.config/compiz/
Choppy animations, even though everything configured correctly
If everything is configured correctly but you still have poor performance on some effects, try disabling CCSM > General Options > Display Settings > Detect Refresh Rate and instead choose a value manually. Tested on both NVIDIA and Intel chips. Can work wonders.
Alternatively, if your chip is NVIDIA and you are experiencing an inadequate refresh rate with "Detect Refresh Rate" enabled in Compiz, it's likely due to an option called DynamicTwinView being enabled by default which plays a factor in accurately reporting the maximum refresh rate that your card and display support. You can disable DynamicTwinView by adding the following line to the "Device" or "Screen" section of your /etc/X11/xorg.conf.d/*.conf, and then restarting your computer:
Option "DynamicTwinView" "False"
Doing so will allow XrandR to accurately report the refresh rate to anything that detects it, including Compiz. You should be able to leave "Detect Refresh Rate" enabled and get excellent performance. Once again, this only applies to NVIDIA chips.
Fix GNOME screenshot
To re-enable gnome-screenshot (the default behavior caused by hitting PrtScn) simply go to Settings Manager>Commands and map 'gnome-screenshot' to the 'PrtScn' key. This is advantageous because you can also use the Compiz Fusion 'Screenshot' plugin at the same time since the action that enables it is Super+Button1 thereby giving you two methods to do a screen capture (one of which gives a full screen capture in a single keystroke).
Get GNOME workspace switcher work with Compiz Fusion
In older versions of Compiz, the Gnome Workspace Switcher applet would actually work with Compiz Fusion (i.e. rotate cube/move plane etc.), but recent versions seem not to. This is due to a new feature introduced in Compiz, which allows real seperate workspaces. For example, if you have a desktop plane with four planes, and have four desktops enabled in Gnome, it sums up to a total of 16 different workspaces. Currently, there is no animation associated with "real" workspace changing. To get the Workspace Switcher work, set the following options in GConf:
/apps/compiz/general/screen0/options/number_of_desktops = 1 /apps/compiz/general/screen0/options/hsize = 4 (this is an example) /apps/compiz/general/screen0/options/vsize = 1 (this is an example)
Screen flicks with NVIDIA card
To fix it, create the following:
/etc/modprobe.d/nvidia.conf
options nvidia NVreg_RegistryDwords="PerfLevelSrc=0x2222"
Setting the window manager back to Metacity after uninstall
Removing Compiz with pacman does not set your window manager back to metacity. This can result in no window borders being drawn, an inability to minimize, and an inability to change the focus. To change it back, run gconf-editor. Use this to set the value of the key /desktop/gnome/session/required_components/window_manager from "compiz" to "metacity". Log out and back in for changes to take effect.
See also
- Troubleshooting page on compiz.org
- Compiz website, including wiki and forum