[window management] add an 'opaque' flag for the shell so that other surfaces are not composited

[Florian Boucault]

Each QtQuick window that does not need to be transparent (e.g. dash) used by the shell needs to be set the 'opaque' flag supported by qtubuntu:
  view = new QQuickView();
  view->setProperty("opaque", opaque);

This will result in increased rendering performance.

[Florian Boucault (fboucault)]

Won't work until the shell is split up into multiple windows (one for indicators, one for launcher, one for dash).

[Pat McGowan (pat-mcgowan)]

is this still valid?

[Florian Boucault (fboucault)]

Still valid.

[Michał Sawicz (saviq)]

It's not clear whether we're going to split the shell into separate components in the end.

[Florian Boucault (fboucault)]

If you don't do it you will be using more memory than necessary. For example when in an app, you only need a surface as big as the launcher to show the launcher. Right now the surface is the size of the screen.

[Florian Boucault (fboucault)]

Also, it's not about splitting the shell into separate components but in separate QQuickWindows.

[Florian Boucault (fboucault)]

And it's not just memory we are wasting but also a ton of GPU cycles given the massive overdraw it incurs.
I imagine fixing this bug would increase performance very very significantly.

[Michał Sawicz (saviq)]

This will be out of scope once QtCompositor gets in.

[Launchpad Janitor (janitor)]

[Expired for Unity 8 because there has been no activity for 60 days.]