Instead of requiring a singleton MetaBackgroundActor for the screen,
allow creating multiple copies that internally share a single
CoglTexture behind the scenes. This will be useful for allowing
multiple views of the screen background with different rendering
options.
https://bugzilla.gnome.org/show_bug.cgi?id=656433
When there was no root background pixmap, we were using a 1x1 repeating
texture as a simple way of drawing a solid color without adding a
second code path. However, when that 1x1 texture was combined into
a larger "atlas texture", hardware repeat couldn't be used, so a
small inefficiency from this approach became an enormous inefficiency
as clutter drew every pixel of the background as a separate rectangle.
https://bugzilla.gnome.org/show_bug.cgi?id=652507
If mutter is going to be a "real" library, then it should install its
includes so that users can do
#include <meta/display.h>
rather than
#include <display.h>
So rename the includedir accordingly, move src/include to src/meta,
and fix up all internal references.
There were a handful of header files in src/include that were not
installed; this appears to have been part of a plan to keep core/,
ui/, and compositor/ from looking at each others' private includes,
but that wasn't really working anyway. So move all non-installed
headers back into core/ or ui/.
https://bugzilla.gnome.org/show_bug.cgi?id=643959
Since we aren't depending on Clutter 1.5 or using the new
CoglPipeline name elsewhere, we need to stick to the old
COGL_MATERIAL_WRAP_MODE_* names, which are provided with
compatibility defines in Clutter 1.4.
Pointed out by Rico Tzschichholz
If we have repeats on for a full-sized image, then if the background
is displayed scaled (for example, in a desktop preview mode) then we
can get artifacts along the edge of the background where the repeat
of the opposite edge is blended in by bilinear scaling. So turn off
repeats when the screen and background image sizes match.
https://bugzilla.gnome.org/show_bug.cgi?id=634833
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
