I'll be honest. I'm a dude who's got nothing that much to lose. No reputation, not that popular (wait!, isn't that the same ;-)) as being pretty much a "no-body" gives me the freedom to say things like, "well even it's been few months, I haven't tested the Unity 2D interface!, until today".What!... :/ parley ;-).
The main reason for this is actually because of the Qt toolkit. I have nothing against (well, at least not that much) nor the believe systems of the Qt "philosophy" which is clearly not that compatible with GNU after considering a bit of history, even though it's released under it, now owned by Nokia.
Because of the past "actions" I guess I'm a bit scared by it. Anyhow, let me come back to the topic. By default the original 3D Unity interface is actually a plug-in that runs on top of the Compiz (an OpenGL composition manager) thus it requires some GPU power + system resources in general which is the reason why my old Laptop cannot keep up with it any more.
|Still comes with few effects such as app-launcher transparency, drop shadows, etc thanks to Metacity's advanced compositing effects...|
But you can still enable few of the options manually if you like by using a small app called 2d desktop settings, otherwise you'll miss that transparent applauncher, etc.
This is pretty simple actually. Now they have a dedicated PPA for that which is enabled for the 11.04 version. You can install Unity 2D (Qt) in Ubuntu 11.04 Natty Narwhal by using the below command.
sudo apt-get install unity-2dThe installation in Ubuntu 10.10 requires the adding of the PPA since it's not enabled by default. So the 10.10 users, please use the below command instead.
sudo add-apt-repository ppa:unity-2d-team/unity-2d-dailyBy default the 2D desktop comes the Compiz compositing manager completely disabled. But it still comes with few "advanced" Metacity WM compositing effects enabled such as drop shadows, transparency effects, etc nonetheless.
sudo apt-get update
sudo apt-get install unity-2d
sudo apt-get dist-upgrade
|Notice the "non-transparent" application-launcher after disabling Metacity compositing effects completely...|
Well as promised, when comparing with the default Unity 3D, it's a hell lot faster! (after disabling the Metacity compositing effects especially). Although the Unity 3D also comes with very little customizations... which is also the case with the 2D version but I guess we should give Ubuntu developers few more months and wait for the upcoming Ubuntu 11.10 release which "would" give the users a better controllability that it's now.
You can also change few of the (2 or 3 actually) Unity-2D's app-launcher related settings by using the below command in you Terminal.
Then from the window that you get, from your left go to:"Desktop" -> "unity-2d" - "launcher".
Now when you click on the "launcher", you'll see to your right few options such as changing the hide-modes, super key enable/disable, preserve screen for the launcher all the time, etc.
Anyhow as a final note, if you're struggling to run the 3D default Unity desktop module with your "old" PC but still would like to get a "taste" of "that desktop" without buying a new PC or a Laptop :).... then apart from the fact that it's written using the Qt toolkit... I'm pretty impressed with its performance and stability, so far.