When we try to update the FB, we might face the case in which the effect target
framebuffer does not need any redraw, because it's already properly sized and
scaled, but the filter applied to the pipeline is not, because it has been
computed for a non-fractional scaling.
This is happens for example to clutter actors with a flattening effect (i.e.
override redirect mode set), that might have been generated properly for a
celied scaling level, but when we go fractional we need to ensure to use a
linear filter, as the 1:1 texel:pixel assumption is not true anymore.
https://bugzilla.gnome.org/show_bug.cgi?id=765011https://gitlab.gnome.org/GNOME/mutter/merge_requests/3
At this level we use ceiled resource-scale when painting fractional value
When using fractional scaling we still need to create an integer-sized
texture and then we should paint it using a size which is proportional
to the real actor size ratio, and only paint a subsample of it, but this
doesn't seem to work properly with some weird scaling values.
Then, it's just better to draw the texture ceiled and then we scale it
down to match the proper actor scaling at paint level.
https://bugzilla.gnome.org/show_bug.cgi?id=765011https://gitlab.gnome.org/GNOME/mutter/merge_requests/3
`ClutterOffscreenEffect` had been getting the wrong bounding box in the
case of clones and descendents of clones, causing visibly incorrect
clipping. This was due to `clutter_actor_get_paint_box` only ever being
given the source actor during a paint (which is correct) and not the clone.
Even if we weren't painting a clone but an offscreened descendent of a
clone (like in gnome-shell's desktop zoom), we would get the wrong result.
Fortunately we don't need to know the actual clone/actor being painted so
don't need to call the problematic `clutter_actor_get_paint_box` at all.
The solution is to only keep untransformed rendering in the FBO and leave
the correct transformation for later. The correct clone/actor's
transformation is already set for us as the current cogl modelview matrix
by `clutter_actor_paint`.
Bonus optimization: This all means we don't need to keep `last_matrix_drawn`
or force a full repaint every time some part of the transformation changes.
Because the FBO contents are no longer affected by transformations. As it
should be. In other words, offscreen-effected actors can now move around
on screen without themselves being repainted.
Special thanks to Mai Lavelle for identifying the cause of the problem.
Fixes:
https://bugzilla.gnome.org/show_bug.cgi?id=789050,
https://bugzilla.gnome.org/show_bug.cgi?id=659523#c9,
https://gitlab.gnome.org/GNOME/mutter/issues/196,
https://gitlab.gnome.org/GNOME/mutter/issues/282,
https://gitlab.gnome.org/GNOME/gnome-shell/issues/387,
https://launchpad.net/bugs/1767648,
https://launchpad.net/bugs/1779615
All those effects have the same basic pattern of setting a
color of a pipeline, then drawing a rect with cogl_rectangle().
Thus, replacing those was as easy as retrieving the draw
framebuffer and calling cogl_framebuffer_draw_rectangle() on it.
If texture allocation fails (e.g. on an old GPU with size limit 2048)
then `update_fbo` would return `FALSE` but leaves `priv->offscreen`
as non-NULL. So the next paint will try to use the offscreen with a
`NULL` texture and crashes. The solution is simply to ensure that
`priv->offscreen` is NULL if there is no `priv->texture`, so the default
(non-offscreen) paint path gets used instead.
Bug reported and fix provided by Gert van de Kraats.
https://launchpad.net/bugs/1795774
Mutter (and libmutter users) are the only users of this version of
cogl, and will more or less only use the cogl-1.0, cogl-2.0 and cogl
experimental API variants, and having the possibility of having
different API versions of the same API depending on what file includes
it is error prone and confusing. Lets just remove the possibility of
having different versions of the same API.
https://bugzilla.gnome.org/show_bug.cgi?id=768977
In cogl use cogl-config.h and in clutter use clutter-build-config.h. We
can't use clutter-config.h in clutter because its already used and
installed.
https://bugzilla.gnome.org/show_bug.cgi?id=768976
