Revert all the work that happened on the master branch.
Sadly, this is the only way to merge the current development branch back
into master.
It is now abundantly clear that I merged the 1.99 branch far too soon,
and that Clutter 2.0 won't happen any time soon, if at all.
Since having the development happen on a separate branch throws a lot of
people into confusion, let's undo the clutter-1.99 → master merge, and
move back the development of Clutter to the master branch.
In order to do so, we need to do some surgery to the Git repository.
First, we do a massive revert in a single commit of all that happened
since the switch to 1.99 and the API version bump done with the
89a2862b05 commit. The history is too long
to be reverted commit by commit without being extremely messy.
ClutterActor has a background-color property, now; we should use it for
the Stage, re-implement the color property in terms of background-color.
and deprecate the Stage property.
The depth cueing through GL fog has been broken for a long while, now.
The fog-related API in Clutter is ridiculously limited, and harks back
to simpler times; the ClutterFog structure is not enough to express all
the GL fog machinery, and required application code to connect to the
Stage's paint implementation and drop into Cogl directly.
Additionally, the fixed pipeline fog machinery in GL simply does not
work with premultiplied alpha, unless you use a shader - and in that
case it would only work for textures. Let's deprecate it, and just
don't do anything if somebody has the brilliant idea of setting the
:use-fog property to TRUE.
The clutter-stage.h header still has a bunch of macros that have, for
reasons unknown[*], survived the 1.0 API cut and have long since been
deprecated. Let's hide them under the deprecated/ carpet and let us
never speak of them ever again.
[*] pretty sure alcohol or other psychotropic substances were involved
but I take the 5th on that.