UIFe: Spread - center the workspace switcher to account for the launcher and pane

For Oneiric, the workspace spread should appear as shown in the attached screenshot. Note that this bug does not apply to 12.04

Patch reviewed and approved by design for Oneiric UIFE.

Thanks Sam, great work ;-)

Added updated screenshot to reflect recent changes to scaling algorithm

I might just comment on the various sections of the code that's changed in order to bring this to place and add a few rationales as to why we're doing this:

WHY WE'RE DOING THIS:
=====================

Partial implementations of what we want from the workspace switcher are already implemented in Unity-2D, such as the layout algorithm that it uses. In Unity-3D we're using the upstream Expo plugin for compiz which hasn't been given all that much attention lately, and it being used as a drop in replacement for what we actually want. Thankfully, the expo plugin is fairly easy to change and we can adapt what was given to us by upstream into something closer to the actual design downstream.

WHAT HAS CHANGED
======================
This branch changes the following things:
 * Inactive viewports have a dot-pattern displayed above them and are faded out and desaturated (30~ line change)
 * The selected viewport has a glow around it (imported logic from this from the group plugin, which has been well tested) (Add 300~ lines)
 * Click drag uses the XC_fleur cursor to have a "hand" dragging the window rather than an arrow. (4 line change)
 * Added X offset and Y offset options for the layout (20~ lines)
 * Changed option defaults

CONTINGENCY PLAN
======================
All of these things are implemented as options, if distro doesn't want them, you can turn the option down to its minimum value and there will be no change evident

DOCUMENTATION
======================
There is no change in behaviour, the only change that will be needed to make to documentation is that the selected viewport now has a glow around it instead of being not darkened and desaturated and screenshots will need to be updated

I agree that this doesn't have an impact on the current documentation, so from the Docs Team, I'm ok with this change which looks like it noticeably improves the workspace switcher. Thanks for the screenshots and text descriptions!

@smspillaz; any word on when this change will land?

as soon as the release team acks it

If this change can be landed before beta 2 freeze, consider it acked. :)

If it can't be included before the freeze, I'd like to get pitti to comment on it, before we include it to make sure the other desktop considerations are understood.

Status changed to 'Confirmed' because the bug affects multiple users.

This bug was fixed in the package compiz - 1:0.9.5.94+bzr2803-0ubuntu4

---------------
compiz (1:0.9.5.94+bzr2803-0ubuntu4) oneiric; urgency=low

  * debian/profile_upgrades/com.canonical.unity.unity.02.upgrade:
    - upgrade the settings for the expo changes (LP: #837545)
  * debian/patches/01_ctrl_alt_*tea*.patch:
    - make Ctrl + Alt + T the default in compiz too as if you unity --reset
      to reset all the keys in gconf, it will revert the associated key
      for metacity in gnome-control-center
 -- Didier Roche <email address hidden> Thu, 15 Sep 2011 19:59:40 +0200

This bug was fixed in the package compiz-plugins-main - 1:0.9.5.94+bzr20110915-0ubuntu1

---------------
compiz-plugins-main (1:0.9.5.94+bzr20110915-0ubuntu1) oneiric; urgency=low

  * New upstream snapshot:
    - UIFe: Spread - center the workspace switcher to account for the
      launcher and pan (LP: #837545)
  * debian/patches/01-grid-fix-rev87.patch:
    - removed in upstream snapshot
 -- Didier Roche <email address hidden> Thu, 15 Sep 2011 19:59:56 +0200

It will be in the next upload

Fix missing upstream. Was only merged into an oneiric branch.