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Author SHA1 Message Date
Robert Mader
eede3d1836 wayland/actor-surface: Remove some needles redirections
We already interact with the `MetaShapedTexture` directly.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1978>
2021-08-28 13:58:48 +02:00
Jonas Ådahl
0330ce1f15 context: Make the context own MetaWaylandCompositor
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1861>
2021-07-15 11:34:37 +02:00
Robert Mader
a09c914230 wayland/actor-surface: Call ensure_size_valid() on shaped-texture
Use the new API to make sure the shaped texture has a valid size
during the next layout phase.

This is needed here because, quoting the previous commit:

When the texture size is invalidated using `invalidate_size()`, the new
size will only get calculated the next time `update_size()` is
called. This happens e.g. in `meta_shaped_texture_get_preferred_size()`
via `ensure_size_valid()`.

`update_size()` can chain up to `clutter_content_invalidate_size()`
as well as emitting a `size-changed` signal. If this happens during
layout, the result is a 'change the layout conditions during layout'
issue, causing heavy breakage in e.g. the Shell overview.

To fix this, expose `ensure_size_valid()` as API so callers can make
sure the texture has a valid size without creating redundant size
invalidations calls.

Note that if a buffer with a new size is attached we already trigger
`update_size()` explicitely, avoiding such situations.

Closes https://gitlab.gnome.org/GNOME/mutter/-/issues/1718

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1799>
2021-03-29 15:47:25 +00:00
Robert Mader
71f03a718d wayland/actor-surface: Always set opaque region on alpha-less textures
Wayland clients using buffers without alpha channel are not expected to
set an opaque region. However, we rely on the opaque region for the fast
painting path in `MetaShapedTexture`.

Thus, make sure to always set an opaque region internally in those cases.
For X11 clients, wo do so already.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1463
2020-10-02 15:09:12 +00:00
Jonas Dreßler
0b9a71ea3c wayland/surface: Don't update outputs recursively on mapped changes
There's no need to update the outputs recursively in case the actor gets
mapped or unmapped. That's because mapping happens recursively itself,
so if a window with multiple subsurfaces is shown, all subsurfaces will
receive a "notify::mapped" signal.

Since this was the only remaining user of
meta_wayland_surface_update_outputs_recursively(), we can now remove
that function.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1358
2020-08-29 12:40:11 +00:00
Jonas Dreßler
abdbc14ca8 wayland/actor-surface: Update outputs on stage-views changes
ClutterActors new "stage-views-changed" signal fits pretty well for the
updating of wl_outputs a MetaWaylandActorSurface is on: With that signal
we get notified if the surface moved to a different CRTC, of which every
output has at least one.

So start listening to that signal, which fixes a bug where the wl_output
of a surface changes, but its allocation remains the same (which means
no signals triggering an update of the outputs will be emitted) and no
enter/leave events for the new wl_outputs are sent to the client. This
can happen when a monitor is hotplugged but the new allocation is
exactly the same as the old one even though it's on a different monitor.

Since the "stage-views-on-changed" signal will also get emitted when a
parent actor of the surface is moved, this means we can now remove the
call to meta_wayland_surface_update_outputs_recursively() on window
position changes or the completion of window-effects.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1358
2020-08-29 12:40:11 +00:00
Jonas Ådahl
066bc5986d wayland: Drive frame callbacks from stage updates
Don't tie frame callbacks to actor painting, as it may end up in
situations where we miss sending frame callbacks when we should have. An
example of this is when a surface is partially off screen, and then
reports damage that is fully off screen. When this happen, we are likely
not to repaint anything, thus we won't send any frame callbacks even
though it's "suitable" for rendering again, as the surface is not on a
separate workspace or fully obscured.

Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/817
Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1152

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1218
2020-05-26 16:46:57 +02:00
Jonas Dreßler
c65f63b647 wayland/actor-surface: Don't notify geometry-changed on mapped changes
There's no reason to notify the surface that its geometry changed when
the visibility of the actor changes. This is only needed to update the
outputs of the surface, so do that directly instead.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1235
2020-05-26 14:54:57 +02:00
Jonas Dreßler
79d981aac9 wayland/actor-surface: Factor in mapped clones in mapped check
We started listening to notify::mapped with commit
5eb5f72434 in order to emit
wl_surface.leave events consistently when a surface gets hidden. This
caused a problem with the ClutterClones used in the overview, since
those temporarily map and unmap the windows for painting, spamming
wl_surface.leave and enter events to all surfaces.

We can easily fix that by also treating mapped clones as mapped, which
means the surface should also be on a wl_output when the overview is
shown.

Fixes https://gitlab.gnome.org/GNOME/mutter/-/issues/1141

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1235
2020-05-26 14:54:57 +02:00
Jonas Dreßler
e68bb27df2 wayland/actor-surface: Don't listen to notify::position signal
We started listening to "notify::position" on surface actors with commit
08e4cb54. This commit was done to fix a regression from commit cf1edff9,
which forgot to handle some cases like the actual WindowActor and not
the SurfaceActor (which is a child of the WindowActor) moving (that was
fixed by listening to MetaWindows "position-changed" signal). Also that
commit introduced meta_wayland_surface_update_outputs_recursively(),
which updates the outputs of all (sub-)surfaces in case any position
changed and made sure subsurfaces also get their outputs updated in case
the parent actor moved.

Connecting to the "notify::position" signal, which the above commit also
did is now superflous though because position changes will queue a
relayout and the actors allocation will change during the next
allocation cycle, notifying the "allocation" property which we also
listen to.

So save some resources and stop listening to that signal.

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1235
2020-05-26 14:52:15 +02:00
Jonas Ådahl
47002bf0cd wayland/surface: Put buffer reference on heap
Currently a buffer use count always reaches zero before it is replaced.
This is due to the fact that at the point a new buffer is attached, the
last potential user releases it (the stage) since the currently
displayed frame has a composited copy of the buffer.

This may however change, if a buffer is scanned out directly, meaning it
should not be released until the page flip callback is invoked.

Prepare for this by making the buffer reference a heap allocated struct,
enabling us to keep a pointer to it longer than the buffer is attached.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/798
2020-04-16 10:43:34 +02:00
Robert Mader
0ada90024f wayland/actor-surface: Check for MetaXwaylandSurface instead of window type
The previous check would not ignore subsurfaces. Use the chance to directly
check for the surface role instead - it's much cleaner.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/1082
2020-02-29 19:44:01 +00:00
Jonas Ådahl
54194e67e3 wayland/surface: Move relative coordinate calculating to roles
The role determines how a relative coordinate is calculated. More
specifically, using clutters API to transform coordinates is only
accurate right after a clutter layout pass but this function is used
e.g. to deliver pointer motion events which can happen at any time. This
isn't a problem for Wayland clients since they don't control their
position, but X clients do and we'd be sending outdated coordinates if a
client is moving a window in response to motion events.

This was already done already, but now move the Xwayland specific logic
to the Xwayland surface role, keeping the generic transformation logic
in the generic actor surface role.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/835
2020-02-19 22:34:28 +00:00
Jonas Ådahl
c0c74484bc wayland: Don't access MetaWaylandSurface::window directly
It'll be moved to the role owning it, accessed via a helper function
implemented by the role. Currently it still just fetches the field in
MetaWaylandSurface.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/835
2020-02-19 22:34:28 +00:00
Robert Mader
1981449776 wayland/actor-surface: Do not set opaque region for XWayland clients
XWayland clients get their opaque region set from their window, not the
surface. Doing both resulted in the surface constantly overwriting the
opaque region - effectively disabling culling of XWayland clients.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/1049
2020-02-12 01:52:38 +01:00
Robert Mader
ae1768bf4f wayland/actor-surface: Do not use geometry scale to constrain regions
The regions and the surface size are all in surface coordinates, thus
don't use the geometry scale, otherwise we might not clip scaled actors
enough.

See also https://gitlab.gnome.org/GNOME/mutter/merge_requests/148

https://gitlab.gnome.org/GNOME/mutter/merge_requests/1036
2020-02-07 18:05:49 +01:00
Jonas Ådahl
6d15231f10 wayland/actor-surface: Always consider unmapped actors not on output
This avoids using bogus geometric values from an unmapped actor to
determine whether an actor is on a logical monitor or not. This would
happen when committing to a subsurface of a yet to be mapped toplevel.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/961
2020-01-10 16:01:22 +00:00
Jonas Ådahl
f0df07cba3 wayland/surface: Move shaped-texture synchronization to actor surface
As with most other state that ends up being pushed to the actor and the
associated shaped texture, also push the texture and the corresponding
metadata from the actor surface. This fixes an issue when a toplevel
surface was reset, where before the subsurface content was not properly
re-initialized, as content state synchronization only happened on
commit, not when asked to synchronize.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/961
2020-01-10 16:01:22 +00:00
Jonas Ådahl
fe7bece31e wayland/surface-actor: Reset and sync subsurface state when resetting
A actor surface may be reset by an xdg_toplevel if a NULL buffer is
attached. This should reset the actor state of the toplevel to an empty
state, while unmapping the previous actor. Subsurfaces, however, should
stay intact, including their relationship to the toplevel. They should
also not be yanked away from the actor of the actor surface prior to it
resetting, so that a window-destroy animation can include the subsurface
actor.

This fixes a potential crash when a subsurface tries to commit to its
wl_surface after the destroy animation of the toplevel has finished, as
the actor would at that point have been destroyed and cleared from the
actor surface struct, causing a segmentation fault.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/961
2020-01-10 16:01:22 +00:00
Jonas Ådahl
fcfe90aa9f wayland: Replace manual GNode subsurface iteration with macro
Similar to wl_list_foreach(), add
META_WAYLAND_SURFACE_FOREACH_SUBSURFACE() that iterates over all the
subsurfaces of a surface, without the caller needing to care about
implementation details, such as leaf nodes vs non-leaf nodes.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/961
2020-01-10 16:01:21 +00:00
Jonas Ådahl
d02c124e1d wayland/surface-role: Rename commit() vfunc apply_state()
The vfunc is not called when a surface commits its state, but when the
state is applied. Make this clearer by changing the name to
"apply_state" (and "pre_apply_state").

https://gitlab.gnome.org/GNOME/mutter/merge_requests/907
2019-12-09 10:09:40 +01:00
Jonas Ådahl
bbec8abb68 wayland/surface: Rename MetaWaylandPendingState to MetaWaylandSurfaceState
The name didn't communicate it was about surface state, and it somewhat
confusingly had the name "pending" in it, which could be confused with
the fact that while it's used to collect pending state, it's also used
to cache previously committed pending state.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/907
2019-12-09 10:09:40 +01:00
Jonas Ådahl
0e5a5df5fe wayland/actor-surface: Always store away frame callbacks on commit
We're expected by MetaWaylandSurface to always pick the frame callbacks
out from the pending state when committing (applying) so that no frame
callbacks are unaccounted for. We failed to do this if our actor for
some reason (e.g. associated window was unmanaged) was destroyed. To
handle this situation better, store away the frame callbacks until we
some later point in time need to pass them on forward.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/893
2019-11-07 12:56:58 +00:00
Jonas Ådahl
d49d10b14f wayland/actor-surface: Queue redraw for frame callback
A frame callback without damage is still expected to be responded to.
Implement this by simply queuing damage if there are any frame callbacks
requested and there is no damage yet. If there already is damage,
we'll be queued already, but with more correct damage. Without we simply
need to make sure we flush the callbacks if any area of surface is not
occluded.

Fixes: https://gitlab.gnome.org/GNOME/mutter/issues/457

https://gitlab.gnome.org/GNOME/mutter/merge_requests/839
2019-10-10 10:01:05 +00:00
Jonas Ådahl
ca318c1520 wayland/actor-surface: Pass actor surface to actor destroy handler
Correct silly mistake where the MetaWaylandSurface was passed as the
user_data of the surface actor destroy signal handler, instead of the
expected MetaWaylandActorSurface.

Fixes: https://gitlab.gnome.org/GNOME/mutter/issues/844
2019-10-04 13:47:18 +02:00
Jonas Ådahl
cbb4f6c892 wayland/actor-surface: Handle surface actor destruction
A surface actor may be destroyed without the backing Wayland surface
being destroyed yet, e.g. by the window being unmanaged. Handle this by
listening on the "destroy" signal and making late requests (e.g.
wl_surface_commit()) resilient against the lack of a surface actor.

Fixes: https://gitlab.gnome.org/GNOME/mutter/issues/838

https://gitlab.gnome.org/GNOME/mutter/merge_requests/825
2019-10-03 22:13:25 +00:00
Jonas Ådahl
092b3edb51 wayland/actor-surface: Add actor clear helper
No functional changes.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/825
2019-10-03 22:13:25 +00:00
Robert Mader
bba8f6c53e wayland/actor-surface: Turn get_geometry_scale() into a vfunc
This allows us to implement more sophisticated logic for the different
cases. For DnD surfaces, use the geometry scale of the monitor where
the pointer is, instead of incorrectly assuming '1' as it was before.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/780
2019-09-27 15:48:36 +00:00
Robert Mader
77229f99b8 wayland: Implement subsurface.place_below() for parents
Flatten the subsurface actor tree, making all surface actors children
of the window actor.
Save the subsurface state in a GNode tree in MetaWaylandSurface, where
each surface holds two nodes, one branch, which can be the tree root
or be attached to a parent surfaces branch, and a leaf, which is
used to save the position relative to child branch nodes.

Each time a surface is added or reordered in the tree, unparent all
surface actors from the window actor, traverse all leaves of the
tree and readd the corresponding surface actors back to the window
actor.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/664
2019-08-27 11:31:00 +03:00
Georges Basile Stavracas Neto
fb9e8768a3 window-actor: Handle geometry scale
Geometry scale is applied to each surface individually, using
Clutter scales, and not only this breaks subsurfaces, it also
pollutes the toolkit and makes the actor tree slightly too
fragile. If GNOME Shell mistakenly tries to set the actor scale
of any of these surfaces, for example, various artifacts might
happen.

Move geometry scale handling to MetaWindowActor. It is applied
as a child transform operation, so that the Clutter-managed
scale properties are left untouched.

In the future where the entirety of the window is managed by a
ClutterContent itself, the geometry scale will be applied
directly into the transform matrix of MetaWindowActor. However,
doing that now would break the various ClutterClones used by
GNOME Shell, so the child transform is an acceptable compromise
during this transition.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/409
2019-08-23 13:23:07 +00:00
Georges Basile Stavracas Neto
c747be84d9 wayland: Don't scale input and opaque regions
Leave them at surface coordinates and let MetaSurfaceActor
and MetaShapedTexture handle the interactions between buffer
and geometry scale.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/409
2019-08-23 13:23:07 +00:00
Georges Basile Stavracas Neto
d3f30d9ece wayland/actor-surface: Set geometry scale in surface actor
Now that MetaShapedTexture is a ClutterContent implemetation that
is aware of its own buffer scale, it is possible to simplify the
event translation routines.

Set the geometry scale in MetaSurfaceActor, and stop adjusting the
surface scale when translating points. Also remove the now obsoleted
meta_wayland_actor_surface_calculate_scale() function.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/409
2019-08-23 13:23:07 +00:00
Georges Basile Stavracas Neto
75cffd0ec4 shaped-texture: Implement ClutterContent
MetaWindowActor is the compositor-side representative of a
MetaWindow. Specifically it represents the geometry of the
window under Clutter scene graph. MetaWindowActors are backed
by MetaSurfaceActors, that represent the windowing system's
surfaces themselves. Naturally, these surfaces have textures
with the pixel content of the clients associated with them.
These textures are represented by MetaShapedTexture.

MetaShapedTextures are currently implemented as ClutterActor
subclasses that override the paint function to paint the
textures it holds.

Conceptually, however, Clutter has an abstraction layer for
contents of actors: ClutterContent. Which MetaShapedTexture
fits nicely, in fact.

Make MetaShapedTexture a ClutterContent implementation. This
forces a few changes in the stack:

 * MetaShapedTexture now handles buffer scale.

 * We now paint into ClutterPaintNode instead of the direct
   framebuffer.

 * Various pieces of Wayland code now use MetaSurfaceActor
   instead of MetaShapedTexture.

 * MetaSurfaceActorWayland doesn't override size negotiation
   vfuncs anymore

https://gitlab.gnome.org/GNOME/mutter/merge_requests/409
2019-08-23 13:23:07 +00:00
Robert Mader
7e2a0ede16 wayland: Move check for present window out of the actor-surface class
All child classes of `MetaWaylandShellSurface` as well as
`MetaWaylandSurfaceRoleXWayland` should only sync their actor if
their toplevel surface has a window. Currently this check is done
in the actor-surface class, but not all surface classes have a
toplevel window, e.g. dnd-surfaces.
Move the check to the right places.

For subsurfaces this assumes that the subsurface is not the child of
a window-less surface (like, as stated above, e.g. a dnd-surface).
If we want to support subsurfaces of window-less surfaces in the future
we have to extend the check here.
But as this is not a regression, ignore this case for now.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/537
2019-05-09 09:06:52 +00:00
Robert Mader
ba7af4f7d3 wayland/surface: Add support for wp_viewporter
This adds the required bits to wayland surfaces and ties them up
to the compositor parts.

It is based on and very similar in nature to buffer transforms.

From the specification:
> The global interface exposing surface cropping and scaling
> capabilities is used to instantiate an interface extension for a
> wl_surface object. This extended interface will then allow cropping
> and scaling the surface contents, effectively disconnecting the
> direct relationship between the buffer and the surface size.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/323
2019-02-06 12:24:03 +00:00
Robert Mader
e4de9ed580 wayland/surface: Add support for buffer transforms
This adds the required bits to wayland surfaces and ties them up
to the compositor parts.

The central part here is to recalculate the surface size accordingly
and to translate surface damage into buffer damage.

The choosen approach additionally lays groundwork for wp_viewporter
support, which is closely related in its nature.

A further explanation of buffer transforms from the specification:
> The purpose of this request is to allow clients to render content
> according to the output transform, thus permitting the compositor
> to use certain optimizations even if the display is rotated.
> Using hardware overlays and scanning out a client buffer for
> fullscreen surfaces are examples of such optimizations.
2018-12-03 19:13:51 +01:00
Jonas Ådahl
d791710197 wayland/xdg-shell: Queue frame callbacks on new actor after resetting
When a xdg-toplevel is reset, the window and actor are recreated, and
all state is cleared. When this happened, we earlied out from the
xdg-toplevel commit handler, which would mean that if the client had
queued frame callbacks when resetting, they'd be left in the pending
commit state, later hitting an assert as they were not handled.

Fix this by queuing the frame callbacks no the new actor, so that they
are emitted whenever the actor is eventually painted.

https://gitlab.gnome.org/GNOME/mutter/issues/240
2018-08-27 11:43:53 +00:00
Carlos Garnacho
b30c907ef9 wayland: Use geometry_scale on opaque regions
This was done for input regions in commit 718a89eb2f (Thanks Jonas
for the archaeology!) but opaque regions follow the same scaling.
This brings less evident issues as opaque regions are just used for
culling optimizations.
2018-08-27 08:38:13 +00:00
Carlos Garnacho
784a774d9c wayland: Fix input/opaque regions calculation on hidpi
Commit 6a92c6f83 unintendedly broke input/opaque region calculations
on hidpi. Most visible side effect is that clicking is only allowed
in the upper-left quarter of windows.

The surface coordinates are returned in logical unscaled buffer
size. We're however interested in actor coordinates (thus real
pixels) here.

As it is a bit of a detour how the scale to be applied is calculated,
refactor a meta_wayland_actor_surface_get_geometry_scale() function
that we can use it here, and use it consistently for surface size and
the given regions.
2018-08-27 08:38:12 +00:00
Robert Mader
6a92c6f83f wayland/actor-surface: Intersect input/opaque region with surface region
As per specification

> The compositor ignores the parts of the input region that
> fall outside of the surface.

> The compositor ignores the parts of the opaque region that
> fall outside of the surface

This fixes culling problems under certain conditions.
2018-08-21 12:24:02 +02:00
Carlos Garnacho
3649795108 wayland: Detach MetaWaylandActorSurface from its actor on dispose
And ensure the actor is no longer reactive even though it might live longer
because of close effects, GCs, and whatnot. This ensures the actor is not
eligible for pointer picking within the destruction of its surface.

Closes: #188
2018-06-14 14:05:10 +02:00
Carlos Garnacho
69ca584168 wayland: Handle get_subsurface() with a role-less parent surface
The order of role creation is undetermined, so we can't account that
the parent surface will have a role (and an actor) at the time of
creating the wl_subsurface role for a child surface.

So we must do it both ways, add the subsurface as a child on
get_subsurface() if the parent already got a role, and lazily add
child subsurface actors to the current one if the parent surface got
it at a later point.

Related: #132
2018-06-08 17:31:25 +02:00
Carlos Garnacho
22485ba36f wayland: Refactor surface actor into MetaWaylandActorSurface
All surface roles that do need a backing actor inherit from this
class, it makes sense to move actor management there. This also
means the MetaWaylandActorSurface is in charge of emitting
::geometry-changed on the MetaWaylandSurface.
2018-04-23 21:31:19 +02:00
Jonas Ådahl
4345906663 wayland: Define abstract role types as actually abstract
They should not be instantiated by themself, only as actual roles.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/5
https://bugzilla.gnome.org/show_bug.cgi?id=791938
2018-02-23 19:07:49 +08:00
Jonas Ådahl
44624736c5 wayland: Push actor state instead of itself pulling
Make the Wayland objects push the state relevant to their role to the
MetaSurfaceActor instead of MetaSurfaceActorWayland pulling the state
from the associated surface.

This makes the relationship between the actor and the objects that
constructs it more clear; the actor is a drawable that the protocol
objects control, not the other way around.

This will make it easier to "detach" a surface actor from a surface,
which is necessary when unmapping a window while the underlying surface
is yet to be destroyed and potentially reused.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/5
https://bugzilla.gnome.org/show_bug.cgi?id=791938
2018-02-23 18:57:47 +08:00
Jonas Ådahl
704b73b041 wayland: Restructure surface role building blocks code
This commit moves out non-core wl_surface related code into separate
code units, while renaming types to fit a common scheme. The changes
done are:

 * ClutterActor based surface roles built upon
   MetaWalyandSurfaceRoleActorSurface. This object has been renamed to
   MetaWaylandActorSurface and related functionality has moved into
   meta-wayland-actor-surface.c.

 * The code related to roles backed by a MetaWindow (i.e. built upon
   MetaWaylandShellSurface) was moved into meta-wayland-shell-surface.c

 * The majority of subsurface related code was moved into into
   meta-wayland-subsurface.c and the object was renamed
   MetaWaylandSubsurface.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/5
https://bugzilla.gnome.org/show_bug.cgi?id=791938
2018-02-23 18:57:40 +08:00