Background handling in GNOME is very roundabout at the moment.
gnome-settings-daemon uses gnome-desktop to read the background from
disk into a screen-sized pixmap. It then sets the XID of that pixmap
on the _XROOTPMAP_ID root window property.
mutter puts that pixmap into a texture/actor which gnome-shell then
uses.
Having the gnome-settings-daemon detour from disk to screen means we
can't easily let the compositor handle transition effects when
switching backgrounds. Also, having the background actor be
per-screen instead of per-monitor means we may have oversized
textures in certain multihead setups.
This commit changes mutter to read backgrounds from disk itself, and
it changes backgrounds to be per-monitor.
This way background handling/compositing is left to the compositor.
https://bugzilla.gnome.org/show_bug.cgi?id=682427
actor_is_untransformed is a function meta-window-group uses to determine
if an actor is relatively pixel aligned and not contorted. It then
returns the coordinates of the actor.
In a subsequent commit will need the function in a different file, so
this commit separates it out.
https://bugzilla.gnome.org/show_bug.cgi?id=682427
meta_window_group_paint tries to carefully figure out which parts of the
scene it can avoid painting. One area it avoids painting is the region of
the screen occupied by an unredirected window (if there's one present).
When subtracting from the visible region, it gets the coordinate spaces
confused, and ends up subtracting the area at the wrong offset. Fix this
by translating the rectangle subtracted from the visible region.
https://bugzilla.gnome.org/show_bug.cgi?id=677116
Instead of getting the x/y of the MetaBackgroundActor with respect to the
parent, use the same logic that we do for windows, fixing the case
where there is a more complex transformation involved.
https://bugzilla.gnome.org/show_bug.cgi?id=681221
Currently when the window group is moved, the visible region set
on the background actor no longer matches the actually visible
region, resulting in flickering around window actors.
Fix by translating the visible region with the window group.
https://bugzilla.gnome.org/show_bug.cgi?id=681221
Some apps that do a lot of rendering on the screen like games, mostly run in
fullscreen where there is no need for them to be redirected doing so does add
an overhead; while performance is critical for those apps.
This can be disabled / enabled at runtime using
meta_enable_unredirect_for_screen / meta_disable_unredirect_for_screen
https://bugzilla.gnome.org/show_bug.cgi?id=597014
Clutter now has some API to get the bounds of the current redraw clip
so Mutter no longer needs to make direct GL calls to get the scissor
rect. This should make it more robust against Cogl or Clutter changing
how it does the clipping.
https://bugzilla.gnome.org/show_bug.cgi?id=654551
Add code to track and draw the root window background. The advantage of doing
it here as compared to in a plugin is that we can use the visiblity smarts
of MetaWindowGroup to optimize out drawing the background when obscured.
If handling other than tracking the _XROOTPMAP_ID property is desired in the
future, more functionality like setting the background from a file or doing
cross-fades can be added.
The new background actor is exposed to plugins via meta_plugin_get_background_actor()
similar to other exposed actors to allow cloning the background for use in
other displays. The actual class is not installed for public consumption at
the moment since it has no useful methods.
https://bugzilla.gnome.org/show_bug.cgi?id=634833
When in a partial stage paint, we can combine that with the visibility
information in MetaWindowGroup to further eliminate unneeded drawing.
Since there is no current Clutter API to access the current clip,
drop to using GL directly.
https://bugzilla.gnome.org/show_bug.cgi?id=634779
Move all objects and functions namespaced with Mutter into the Meta namespace
to get a single consistent namespace. Changes that aren't simply changing mutter
to meta:
MutterWindow => MetaWindowActor
mutter_get_windows => meta_get_window_actors
mutter_plugin_get_windows => meta_plugin_get_window_actors
https://bugzilla.gnome.org/show_bug.cgi?id=628520
