Compiz will be fully integrated in Ubuntu MATE 15.04, but not enabled by default.
To that end I have been working on adding MATE support to Compiz over the last few evenings. I will submitting my changes to the Ubuntu Compiz maintainers, but I'd like to get some testing feedback first. I've back ported my changes to 14.04 and 14.10 and built everything you need into a PPA.
If you are feeling brave, let the destruction begin 
Install Compiz
This first step is only required for Utopic
sudo apt-add-repository ppa:ubuntu-mate-dev/utopic-mate
From here on the instructions are the same for both Ubuntu MATE 14.04 and 14.10.
sudo apt-get update
sudo apt-get dist-upgrade
sudo apt-get install --no-install-recommends compiz compiz-core compiz-mate compiz-plugins compiz-plugins-default compizconfig-settings-manager
You should now have newer version of MATE Tweak and my modified build of Compiz installed. Full disclosure, I have tested on Ubuntu MATE 14.04 and 15.04, but not 14.10. The package for 14.10 are the same as 15.04 so it should work.
Reboot (yes an actual reboot) Now!
This reboot is required so that Compiz can become MATE aware. If you do not reboot "bad stuff" will happen. This reboot step is not going to be required for Ubuntu MATE 15.04 since it will come pre-installed with all the required settings.
Guake or Tilda
PRO TIP! Install guake or tilda and make sure it is running before you try switching window managers with MATE Tweak. If Compiz switching dies horribly you can pull-down guake or tilda using their respective key-binding and then run marco --replace which will get your window manager back.
Switching between Marco and Compiz
After the reboot, log in and open System -> Preferences -> MATE Tweak, choose Windows and then use the Window manager drop down to switch between Marco and Compiz. As soon as you select a window manager it will be replaced and MATE Tweak will close.
You can check which window manager you are using by running the following in a terminal.
wmctrl -m
Glorious success 
or did it die in a fireball of death 
? Let me know in the comments.
Recovering Marco
If it all goes horribly wrong then you can recover Marco using the following commands from guake or tilda or good old Alt+F2.
gsettings set org.mate.session.required-components windowmanager marco
/usr/bin/marco --replace &
Reset Compiz configuration
If Compiz is misbehaving or the settings are somehow inconsistent then you can reset everything back to a clean configuration using the following commands.
marco --replace &
dconf reset -f /org/compiz/
rm -rf ~/.config/compiz-1
rm -rf ~/.cache/compizconfig-1
Now log out and log in again.
Having done the above the next time to run compiz --replace or switch to Compiz using MATE Tweak a fresh Compiz configuration will be generated.
Known issues
- Live switching has been (still is?) a bit hit and miss that can result in the Compiz profile not being accurately created in gsettings.
- Using the AMD/ATI proprietary drivers is report to work and not work in equal measure.
Understanding Compiz integration for Ubuntu MATE
My changes are simple and few.
- I have created a Compiz profile specific for MATE, you can find it in
/etc/compizconfig/mate.ini. - I've modified
/etc/compizconfig/configto include a reference to themate.iniprofile mentioned above. It looks like this:
[general_mate]
backend = gsettings
integration = false
plugin_list_autosort = true
profile = mate
- I have modified
/etc/X11/Xsession.d/65compiz_profile-on-sessionto detect MATE and thenexport COMPIZ_CONFIG_PROFILE="mate". This instructs Compiz to use themateprofile. - I've added a migration script that ensures the
unityshellandunitymtgrabhandlesplugins are not present in the MATE Compiz profile.
I have ported the gnomecomat Compiz plugin to matecompat but because there is still some instability with Compiz under Ubuntu MATE I want to sort those issues out before introducing new code and releasing it.
You can find my Compiz repository here:
compiz (core) - Warn: Unknown option āāindirect-renderingā
