As with the compositor type enum, also have the X11 display policy enum,
as it's also effectively part of the context configuration. But as with
the compositor type, move it to a header file for enums only, and since
this is a private one, create a private variant meta-enums.h.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1861>
The DRM buffers aren't really tied to mode setting, so they shouldn't
need to have an associated mode setting device. Now that we have a
device file level object that can fill this role, port over
MetaDrmBuffer and friends away from MetaKmsDevice to MetaDeviceFile.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1828>
When the MetaWindow resize machinery for toplevels ended up in the
Wayland window implementation, we tried to avoid configuring
not-yet-mapped windows that just had its zero sized dimension pass
through the constraint machinery, resulting in a 1x1 sized window.
If we'd properly set up the min size metadata earlier, that 1x1 would
likely be the minimum size set of a window, which makes things harder to
predict when peeking at side effects.
However, what the side effect peeking intends to do, as documented in
the comment, was to figure out when the client hadn't committed any
buffer yet, i.e. during the initial map, and in those cases avoid
sending that nasty 1x1 size, resulting in silly window sizes. A more
robust way to detect this is instead checking when we shouldn't really
try resize things our own way, and in those cases early out as was done
before.
This means that, for a yet to me mapped window, we only ever want to
send an initial non-zero configuration when 1) it's initially maximized,
2) initially fullscreen, or 3) initially tiled in any way, as those are
the situations where the compositor is the one deciding the size.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1912>
The cancel phase for swipe gestures was not being handled, hence,
Wayland "end" events where not sent to clients when the gesture was
cancelled.
A swipe gesture is cancelled when extra finger(s) are put down on the
touchpad in the middle of the gesture or when some, but not all, of the
fingers are put up.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1857>
Getting crossing events is necessary between client surfaces while
there is a popup grab in effect (e.g. allow press-drag-release in
menus), we should only stick with the focus surface while the pointer
is outside any client surface.
This partially undoes commit 79050004b0 (or, at least, mutter no
longer fixes the bug it claimed to fix). This will be addressed in
gtk4.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1885>
We first initialized the Wayland infrastructure, then the display, but
on shutdown, we first teared down the Wayland infrastructure, then the
display.
Make things a bit more symmetric and tear down the display before
Wayland. This however means we need to tear down some things Wayland a
bit earlier than the rest. For now this is a separate function, but
eventually, it can be replaced with a signal shared by the backend's
'prepare-shutdown' signal.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1863>
This way we can initialize without having any way to retrieve it via
some global variable. This isn't needed now, but will be once Wayland
infrastructure initializiation is done in a single step.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1863>
This is especially important as we might end up here when initializing
the Wayland infrastructure. Later that will be done in one step, meaning
the "get_default()" function will not work properly.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1863>
It might not be there when shutting down, so get it from a more managed
place. Note that this isn't strictly needed right now, but eventually,
the MetaWaylandCompositor pointer will be cleared using a g_clear*()
helper, which clears the pointer before freeing the instance, which
wouldn't work here.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1863>
This will allow us less awkward startup, where previously we had to
pre-initialize Wayland very early so Cogl could bind the Wayland display
when it initialized. Move things around so we bind the Wayland EGL
display when initializing the rest of Wayland infrastructure.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1863>
The callback on_displayfd_ready() would unconditionally set the return
value to TRUE, regardless of the condition.
Use the GIO condition to determine if there was data written and adjust
the return value accordingly.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1851>
We initialize, but might not start, e.g. when a test case just needs a
backend and doesn't start mutter. When cleaning up, we'll still try to
clean up Xwayland integration, and this commit handles cleaning up
without having made the mess.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1856>
We make objects inert when disabling the seat, but we requests may still
have effect. This is especially bad if disabling is followed by
destroying, but also means e.g. set_cursor() not doing an early out
after the pointer capability was disabled.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1822>
MetaDisplay does a lot of things, and is a central part to anything
window management. To let Wayland units have an easier time tearing
down, make it so that the Wayland infrastructure is terminated before
MetaDisplay.
This also makes sure that X11 support is turned off, so that we don't
stumble upon Xwayland terminating due to the Wayland socket connection
being broken. Will mitigate that in a better way in a later commit.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1822>
We might not be the only entity holding on to the X11 GdkDisplay,
meaning the X11 connection will stay alive indefinitely, e.g. if the gjs
context has some reference to it.
Avoid running into issues due to X11 connection errors by setting the
libX11 handlers to no-ops, so when we are terminating; that means the
GDK X11 connection can stay "alive" until its too late, and we'll just
silently ignore any connection errors that may happen due to the
lingering GDK display reference.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1822>
Compositor behaviour when calling `wl_data_device_manager_get_data_device`
for the same seat multiple times is not very clearly defined in
the spec and both Mutter and Weston currently don't handle
the DnD case properly.
While Weston handles DnD only for the last created data device,
Mutter, because of some internal reshuffling, ends up toggling
between two devices.
Properly handling this case requires some bigger changes. So
in order to behave predictable and in line with Weston,
only take the last created data device into account while
still keeping the previous created ones around.
The main affect client here is Firefox, which gets very
confused by the toggling behaviour and becomes more stable
with this patch.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1841>
If a subsurface first gets reordered and afterwards detached from
the parent before the parent surface got commited, we currently
would end up reattaching the subsurface to its previous parent.
While clients should avoid this behaviour, it's legit according
to the spec.
We already prevent similar cases where the subsurface is destroyed -
extend that check to detaching, which includes the destroy case.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1831>
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>
If a client is naive enough to assume that it can set the selection while
it has got no surfaces, mutter will simply ignore the request and leave
the selection unchanged.
This is good and the expected behavior, however the poor client that did
this will enter in an inconsistent state where it "claimed" the selection,
but nobody told it that the wl_data_source is not current.
So, when the client is focused the next time, it will receive wl_data_offers
as usual, but it will still think all the time that it is owning the
selection. In the case of GTK, that takes client-side shortcuts, so any
attempted paste will still bring back the client-side aborted selection.
To fix this, cancel the selection right away if it happened while unfocused,
the client will be able to undo its own failed selection, and not assume
that future offers are its own.
Fixes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1469
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1772>
It seems to be the preferred format of the Mesa V3D driver on
Raspberry Pi 4. If the compositor doesn't advertise it then Mesa will
fallback from `zwp_linux_dmabuf_v1` to `wl_drm`, incorrectly. Meaning
it will keep using a buffer with modifiers on an interface that does
not have modifiers.
Add support for `DRM_FORMAT_ABGR2101010`. It works, and prevents Mesa
from taking its broken fallback path.
Fixes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1520
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1798>
For Xwayland, mutter creates the sockets in the standard /tmp/.X11-unix
directory.
Yet, if that directory already exists, it may have been created by
another user with full control over the created socket.
To avoid that issue, if the directory /tmp/.X11-unix already exists,
check that the permissions are as we expect, i.e. the directory belongs
to either root or the user herself, is writable and has the sticky bit.
Thanks to fabian@ritter-vogt.de for reporting that issue.
https://gitlab.gnome.org/GNOME/mutter/-/issues/1708
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1787>
Unlike other subsurface state, placement operations need to get
applied in order. As per spec:
```
Requests are handled in order and applied immediately to a pending
state. The final pending state is copied to the active state the
next time the state of the parent surface is applied.
```
Having placement operations being part of the subsurface state
makes it difficult to support arbitrary orderings. Make them
part of the parents surface pending state instead.
Closes https://gitlab.gnome.org/GNOME/mutter/-/issues/1691
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1768>
When deciding if `configure` event should be sent,
`meta_window_wayland_move_resize_internal` compares requested window size
with `window->rect` size. However, `window->rect` is only updated when `commit`
is received. So the following sequence produces incorrect result:
1. a window initially has size `size1`
2. `move_resize_internal` is called with `size2`. `configure` is sent
3. `move_resize_internal` is called with `size1` to restore original size,
but `commit` for `size2` haven't arrived yet. So `window->rect` still has size
`size1`, and thus new `configure` is not sent
4. `commit` for `size2` arrives, window changes size to `size2`
Expected window size in the end: `size1`
Actual: `size2`
To fix the issue, take size from pending `configure` events into account.
Fixes https://gitlab.gnome.org/GNOME/mutter/-/issues/1627
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1755>
This commit assumes that cursor surfaces work in a "mailbox" fashion. If
they are painted multiple times before a successful flip, all commits
but the last get discarded, and the last commit gets presented after the
flip succeeds. This is more or less how it works in the atomic backend,
and also more or less how it works in other backends, with the exception
that the cursor painting might fail without any way of knowing. This
assumption is still better than unconditionally discarding all cursor
surface feedbacks as if the cursor painting always fails.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1484>
Regarding the sequence = 0 fallback: in some cases (moving a cursor
plane on atomic amdgpu) we get sequence = 0 in the page flip callback.
This seems like an amdgpu bug, so work around it by assuming a sequence
delta of 1 (it is equal to 1 because of the sequence != 0 check above).
Sequence can also legitimately be 0 if we're lucky during the 32-bit
overflow, in which case assuming a delta of 1 will give more or less
reasonable values on this and next presentation, after which it'll be
back to normal.
Sequence is also 0 on mode set fallback and when running nested, in
which case assuming a delta of 1 every frame is the best we can do.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1484>
The presentation-time protocol allows surfaces to get accurate
timestamps of when their contents were shown on screen.
This commit implements a stub version of the protocol which correctly
discards all presentation feedback objects (as if the surface contents
are never shown on screen). Subsequent commits will implement sending
the presented events to surfaces shown on screen.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1484>
If `meta_xwayland_start_xserver()` returned via an error path, some of
the socket FDs were leaked.
Fix that, and add `steal_fd()` calls to make it clearer that FDs passed
to `g_subprocess_launcher_take_fd()` are transferred to it. There were
no bugs with how `GSubprocessLauncher` was being used.
Spotted while working on
https://gitlab.gnome.org/GNOME/glib/-/issues/2332.
Signed-off-by: Philip Withnall <pwithnall@endlessos.org>
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1738>
X11 clients can use different models of input handling, of which some
may not result focus being set synchronously.
For such clients, meta_focus_window() will not change the focus itself
but rely on the client itself to set the input focus on the desired
window.
Add a new MetaWindow API to check when dealing with such a window.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1716>
In the case that DnD is performed and succeeds, we want to release
the grab early, and let the transfer IPC happen in the back. For
that to happen without a hitch, drag source and offer must be left
related to each other after undoing the grab, even though the default
ungrabbing code does that automatically (indirectly, by unsetting the
drag focus).
In these cases, we used to manually unset the current source, so
this decoupling was skipped. Notably, one missed case is X11 DnD,
so we might end up with the situation there that DnD did succeed,
transfer is ongoing, but the source and offer are already decoupled,
this confused the machinery and missed the finishing XdndFinished
to be emitted to the X11 drag source.
The prior commits prepared for this source/offer decoupling being
a manual operation, this commit avoids doing this automatically
when ungrabbing.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1720>
This object is just being detached, with no code unref'ing it. Do
this whenever the XDnD selection goes unowned, usually a good
indication that the drag source no longer is one.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1720>
When (un)maximizing, (un)fullscreening, the move/resize action is
flagged with 'ACTION_MOVE' and 'ACTION_RESIZE' , while e.g.
'appears-focus' does not.
When a client misbehaved and didn't immediately reply to a configure
request with a commit with the corresponding ack_configure, the
following commit would trigger a oddly timed move, making the window
appear to move back to a previous position.
Avoid this issue by only carrying over the target window position if the
configuration actually contained a new position.
We cannot only rely on the flags however, as e.g. a new position should
be respected during interactive resize, even though only 'ACTION_RESIZE'
is passed in such scenarios.
Do the same for the size, except if the window state dictates that the
size is fixed to a certain size, e.g. being fullscreen or maximized.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1445>
Previously the wl_resource and MetaWaylandGtkSurface corresponding to
any client gtk_surface have been kept around until the exit of the
client due to the client side destroy method not signaling the
destruction to the server. Ideally the protocol would have specified a
destroy request marked as destructor to handle this automatically,
however this is no longer possible due to the destroy method being
implicitly generated in the absence of an explicit request in the
protocol. Adding a destroy request marked as destructor now would
generate a new destroy method that unconditionally would send the
request to the server, which would break clients running on servers not
supporting that request.
So instead of modifying the destroy request add a new "release"
destructor, that indicates to the server that it can release the
resource. This can be optionally be used by clients depending on the
server protocol version.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1307>
The MetaWaylandSurface corresponding to a MetaWaylandGtkSurface can be
destroyed before the MetaWaylandGtkSurface is destroyed. In its destroy
function MetaWaylandSurface however was unsetting the destructor of the
correspnding resource along with the gtk_surface1 interface
implementation. This was done to prevent further gtk_surface1 requests
on a NULLed MetaWaylandSurface, if it has been destroyed before the
MetaWaylandGtkSurface.
It would be enough to just unset the resource implementation, while
keeping the destructor to fix this leak. However the following commit
will rely on the implementation being available after the
MetaWaylandSurface has been destroyed. So instead introduce NULL checks
for all functions that can be called on the gtk_surface1 interface and
do not unset the implementation.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1307>
One for the public channel, and one for the private maintainance
channel. Use the public one for test clients, otherwise tests become
flaky, and the private one for MetaX11Display.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1681>
This commit consolidates DRM buffer management to the MetaDrmBuffer
types, where the base type handles the common functionality (such as
managing the framebuffer id using drmModeAdd*/RMFb()), and the sub types
their corresponding type specific behavior.
This means that drmModeAdd*/RmFB() handling is moved from meta-gpu-kms.c
to meta-drm-buffer.c; dumb buffer allocation/management from
meta-renderer-native.c.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1488>
Current Xwayland has marked the command line option "-listen" as
deprecated in favor of "-listenfd".
Use the pkg-config variable "have_listenfd" (if available) from Xwayland
to determine if we should use that option, to avoid a deprecation
warning when spawning Xwayland.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1682>
Mutter listens to two display connections, one for regular X11 clients
and another one for the so called "managed services".
Once an available display number is found for the regular X11 clients,
mutter would then redo the work to find another available display number
for the managed services.
Yet, it does so starting from the same initial display, which is a waste
of time since it just tried all displays to find the first available
one, so all these, including the regular display it just took, are now
in use.
So instead of starting over from the beginning when looking for a
display available for the managed services, continue from the next
display immediately after the one we found precedently.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1680>
Some X11 servers may not always create a lock file, yet mutter uses the
lock file to find a possible display number and then tries to bind to
the socket corresponding to that display number.
If it fails to bind, it will simply bail out. As a result, if an X11
server is already listening on that display but hadn't created a lock
file, mutter won't be able to start Xwayland.
To avoid that possible issue, make mutter retry with another display
for a given number of tries when binding fails even though the display
was supposed to be available based on the lock file presence.
Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1604
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1669>
The function choose_xdisplay() calls open_display_sockets() which calls
ensure_x11_unix_dir().
We don't need to do that from within the loop though, as the directory
/tmp/.X11-unix is the same regardless of the display number.
Move the call to ensure_x11_unix_dir() from open_display_sockets() to
choose_xdisplay() prior to enter the display loop.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1669>
In case of failure to open the display sockets, we would not propagatre
the error which can cause a crash when trying to show the error message.
Properly propagate the error to avoid the crash.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1669>
In the shutdown paths we check with the X11 display whether there's
remaining clients. However this happens in paths that happen after
the MetaX11Display vanished in the case of Xwayland crash.
Since in that situation the clients are forcibly vanishing too,
skip the client check.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1677>
Closing automatically Xwayland once all relevant X11 clients are gone is
inherently racy, if a new client comes along right at the time we're
killing Xwayland.
Fixing the possible race conditions between mutter, Xwayland and the X11
clients may take some time.
Meanwhile, make that an experimental feature "autoclose-xwayland".
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1673>
Currently, mutter checks for the presence of X11 windows to decide
whether or not Xwayland can be terminated, when Xwayland is started on
demand.
Unfortunately, not all X11 clients will map a window all the time, an
X11 client may keep the X11 connection opened after closing all its
windows. In that case, we may terminate Xwayland while there are some
X11 client connected still, and terminating Xwayland will also kill
those X11 clients.
To avoid that issue, check the X11 clients actually connected using the
XRes extension. The XRes extension provides the PID of the (local) X11
clients connected to the Xserver, so we need to match that against the
actual executable names, and compare with a list of known executables
that we can safely ignore, such as ibus-x11 or gsd-xsettings.
We also check against our own executable name, considering that the X11
window manager is also an X11 client connected to the Xserver.
Also, XRes returning the PID of local clients only is not a problem
considering that Xwayland does not listen to remote connections.
However, if the user spawns a client remotely on another system using
ssh tunneling (ssh -X), only clients which actually map a window will
be accounted for.
Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1537
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1671>
Changes in games between fullscreen and windowed modes may trigger
chaotic situations where the buffer and the frame size temporarily
disagree, producing rectangles with negative width/height. This is
usually followed by other updates that bring the pointer constraint
up to date.
This makes cairo panic and return an "error" empty region, which breaks
deeper down when using the region rectangles to apply the pointer
constraint.
If we hit this situation, ignore the frame rectangle, and just go with
the buffer rectangle.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1655>
Unfortunately there's situations where we can't fully rely on only
crossing events here. One such situation is pointer visibility changes
due to touch interaction, or e.g. after closing the lid.
In these situations the pointer position stays the same, picks the
same actor, yet we want to see the right surface as the pointer focus
again in the wayland side.
This used to happen on the first motion event after the pointer
visibility change before commit ad3f2b0b86, use motion events again
for picking so we don't break these usecases.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1657>
These events may be emitted for touchpoints (in which case they contain
an event sequence). Ignore those as they are not relevant for pointer
picking, and shouldn't influence its focus.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1657>
Just because of implementation details, this is only relevant to Wayland,
and is done via ::effects-completed handlers there. Ideally, Clutter should
notice by itself about effects starting, finishing, and affecting picking.
Doing this in generic code seems slightly cleaner in the interim.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1654>
In the wayland code we are in synchronization with the events that
the ClutterStage is managing at the moment. Asking the ClutterSeat for
the pointer position gets ahead of the current events, and may result
in imprecise coordinates sent in wl_pointer.enter.
To be in consistence with the motion events that might be already
queued, we should ask the stage for the last known coordinates.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1654>
As planned and prepared with the last commits, let ClutterStage take
care of tracking input devices and their respective actors. This means
we now can remove the old infrastructure for this from
ClutterInputDevice.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1633>
To find XWayland output that should be the primary one, iterate through all
XWayland outputs, and compare their geometry to the geometry of the primary
logical monitor.
To avoid possible race conditions (Mutter's monitor configuration already
updated, but Xrandr not yet), set the output both after Randr notifications and
after 'monitors-changed' signal.
https://gitlab.gnome.org/GNOME/mutter/-/issues/1407
Signed-off-by: Aleksandr Mezin <mezin.alexander@gmail.com>
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1558>
When we're running under a polyinstantiated SELinux environment, we'll
likely start with an isolated and empty /tmp, meannig no /tmp/.X11-unix
directory to add things to. To make it possible to still function in
this kind of setup, make sure said directory exists.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1626>
Instead of using native backend platform data specifically, store
this info in ClutterMotionEvent. This includes time in usec since
it's just used for motion events, in the future it could make sense
to make these general to all events again, but it could make sense
to make ClutterEvent structs private before.
In order to express that a motion event has relative motion info,
the CLUTTER_EVENT_FLAG_RELATIVE_MOTION event flag has been added
for it.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1623>
We had code in both backends that sort of independently associated
sequences to slots. Make both transform slots to sequences the same
way, so they may share the implementation convert those back to slots.
This helper now lives in Clutter API.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1623>
We have this as platform-dependent data in the native backend, and
a bunch of fallback code done in place in the evcode users. Stop
making this platform-dependent data, and move it to the relevant
ClutterEvents.
The fallback code for the X11 backend case is about the same, but
now it is done directly by the X11 backend.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1623>
The XIOErrorExitHandler expects (Display *, void *) whereas mutter uses
(Display *, MetaX11Display *).
That causes a warning at build time:
warning: passing argument 2 of ‘XSetIOErrorExitHandler’ from
incompatible pointer type [-Wincompatible-pointer-types]
813 | XSetIOErrorExitHandler (xdisplay, x_io_error_exit, display);
Actually, the MetaX11Display is not even used, so we can just use the
expected API and ignore the value.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1621>
While browsing sysprof profiling reports, I saw surface-commit taking
significant times sometimes; trace attach too, to see whether such
things are due to e.g. texture uploads.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1616>
These use now more of a "pull" model, where they receive update
notifications and the relevant input position is queried, instead
of the coordinates being passed along.
This allows to treat cursor renderers all the same independently
of the device they track. This notifying of position changes should
ideally be more backend-y than core-y, a better location will be
figured out in future commits.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1403>
Instead of letting the wayland bits maintain an always-software
cursor renderer, let the cursor renderer be managed by the backend,
and only hook to it (as we do for pointer cursor) in the wayland
bits.
ATM, make the cursor renderer still always-software, although
ideally we should allow moving the HW cursor management between
renderers.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1403>
Since we schedule frames for each stage view seperately now, surfaces receive
frame callbacks for each stage view they are visible on.
Only emit frame callbacks for the primary stage view.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1468>
For X11 grabs, the pattern matching mechanism would simply ignore
applications which have neither WM_CLASS nor WM_NAME set.
When dealing with an override redirect window however, it is not
uncommon that these window have neither value set as these window are
supposed to be ignored by the window manager.
When the WM_CLASS or the WM_NAME is not set by the client, assume the
value is empty so the pattern matching can allow for these.
https://gitlab.gnome.org/GNOME/mutter/-/issues/1249
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1254>
Commit 8bdd2aa7 would offset the window position by the difference
between the configured window size and the committed size from the
client to prevent the window from drifting while resizing.
This, however, did not take into account the actual geometry scale, so
when using any scale greater than 1, the window would rapidly drift away
due to that offset.
In order to solve this, we need to make sure we store away the pending
window configuration in the stage coordinate space, in order to not
loose precision. When we then calculate the offset given the result from
the client, it'll use the right scalars, while before, one scalar was in
surface coordinates, while the other in stage coordinates.
https://gitlab.gnome.org/GNOME/mutter/-/issues/1490
The semantics for libinput events are not as expected here. Besides
it's pointless, as those should arrive per-slot in a burst, and we
cancel on the first event.
We can simply use the Clutter event for this.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1486
We want to coalesce multiple touch events into the same wl_touch.frame
event. Instead of poking internals to peek the touch events (and their
slots) coming at us before we handle them, simplify things by queueing
the event at a slightly lower priority than events, so we are ensured
to handle all pending input events before sending the event.
If there's no pending events, we can just send the frame event. As it
doesn't make sense to hold any longer.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1486
Implements the "prior window window geometry dimensions" as described in
the documentation of 'xdg_toplevel' request 'unset_maximized':
"If available and applicable, the compositor will include the window
geometry dimensions the window had prior to being maximized in the
configure event."
and 'unset_fullscreen':
"The compositor may include the previous window geometry dimensions in
the configure event, if applicable."
Fixes https://gitlab.gnome.org/GNOME/mutter/issues/792.
If this call is available, we can turn libX11 IO errors (fatal by definition)
into something we can recover from. Try to dispose all X11 resources and close
the display instead, so the compositor can survive the event.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1447
If the MetaX11Display abruptly closed when X11 windows were present,
we would still try to deal with them while freezing/thawing for the
"fade out" animation.
At the bottom of that, the X server may be gone, just try to cope
with it.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1447
The spec states:
```
A sub-surface becomes mapped, when a non-NULL wl_buffer is applied
and the parent surface is mapped. The order of which one happens
first is irrelevant. A sub-surface is hidden if the parent becomes hidden,
or if a NULL wl_buffer is applied. These rules apply recursively
through the tree of surfaces.
```
In the past we relied on Clutter actor behaviour to realize the recursive
part - which then broke in
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/664
when we changed the actor hierachy in regards to subsurfaces.
Explicitly encode the desired behaviour in `MetaWaylandSubsurface`, fixing
the issue and making it future proof.
Closes https://gitlab.gnome.org/GNOME/mutter/-/issues/1384
Mutter sends a proximity-in event before the required tablet tool
resource is properly allocated on the client. This is violating the
Wayland protocol. Because libwayland ignores events for objects it
doesn't know yet, this is not noticeable in most applications. However,
if https://gitlab.freedesktop.org/wayland/wayland/-/issues/176 gets
fixed, these applications would likely crash immediately. Therefore this
PR removes the responsible code which, again, shouldn't have any effect
on client applications as they ignore this event anyway.
Relevant part of the spec:
This event can be received when the tool has moved from one surface to
another, or when the tool has come back into proximity above the
surface.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1427
When we resize a window we send it configure requests with size
suggestion. Some clients, e.g. gnome-terminal will limit its size to a
discrete set given the font size resulting in the size often not being
respected completely, but used as a hint to find a size as large as
possible but not larger than the configured size.
When doing an interactive resize dragging the right or top side of a
window, this caused issues with the configured window size not matching
the one used by the client, as the configured position wouldn't be
correct for the actual size. Fix this by offsetting the position given
the size mismatch offset, making the position again in sync with the
size.
Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1447https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1477
A Meta.WaylandClient() object has a GSubprocessLauncher object
passed externally. Currently this object is kept while the
WaylandClient object exists, but is is only needed until the call
to spawn is made.
This patch frees that GSubprocessLauncher just after that call,
thus freeing those resources.
Fix https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1462
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
The Meta.WaylandClient constructor receives a GSubprocessLauncher
as a parameter, and stores it internally. Unfortunately, its
refcount value isn't increased, which results in the object being
released twice.
This patch fixes this bug.
Fix https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1454
We only did this if we weren't currently doing an interactive resize,
but since the finish_move_resize() is not the actual interactive resize
but the acknowledgment of the configure event that was emitted as a
result, we shouldn't limit ourself to the same flags used during resize.
This fixes temporarly "stuck" position of attached modal dialogs while
they are being resized.
Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1163https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1446
Just because X11/XI uses a particular terminology doesn't mean we
have to use the same terms in our own API. The replacement terms
are in line with gtk@1c856a208, which seems a better precedent
for consistency.
Follow-up to commit 17417a82a5.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1425
This is no longer directly related to DBus messages, but our own event
queue. Change the wording and use CLUTTER_PRIORITY_EVENTS to make it
bolder, even though it's the same than G_PRIORITY_DEFAULT.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1286
We set an idle to coalesce multiple IM events together, as the protocol
requires us to send them in one frame, and unfortunately there is no
idea about whether more IM events are upcoming.
One good hint though are key events generated from the IM, we want to
apply all IM changes before the key event is processed, so make it sure
that the .done event is flushed before the key event is handled.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1286
The clutter_input_focus_filter_key_event() function has been made
a more generic filter_event(). Besides its old role about letting
key events go through the IM, it will also process the IM events
that are possibly injected as a result.
Users have been updated to these changes.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1286
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
Since we now listen to the "stage-views-on-changed" signal (which
"catches" all the changes we want) on MetaWaylandActorSurfaces for
updating the wl_outputs the surface is on, we no longer need to call
meta_wayland_surface_update_outputs_recursively() on all geometry
changes, so remove that signal handler.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1358
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
The X server, including Xwayland, can be compiled with different X11
extensions enabled at build time.
When an X11 extension is built in the X server, it's usually also
enabled at run time. Users can chose to disable those extensions at run
time using the X server command line option "-extension".
However, in the case of Xwayland, it is spawned automatically by the
Wayland compositor, and the command line options are not configurable
by users.
Add a new setting to disable a selected set of X extension in Xwayland
at startup, without needing to rebuild Xwayland.
Of course, if Xwayland is not built with a given extension support in
the first place (which is the default for the security extension for
example), that option has no effect.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1405
If we returned early in one of the checks but already assigned the
surface role, we'd later run into a double-free and crash. Just do
the checks at the beginning.
Also add a missing return statement that was left out in commit
88ff196fe3 and tighten the parent surface check.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1415
The spec allows `parent_resource` to be `NULL`, requiring the parent
surface to get specified by some other protocol. Send a protocol error
with some meaningful explanation instead of crashing.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1408
Clients can set minimum and maximum to identical values to indicate a
fixed-size window. A compositor can ignore these requests and thus a client
has to ensure these limits.
To support clients that do not ensure these size limits by themselves and
to skip unnecessary function calls, we will prevent resizing requests by
the client if a fixed-size has been requested.
https://gitlab.gnome.org/GNOME/mutter/-/issues/1331
Just as wl_shm, hook up the Wayland DMA-BUF protocol to the 64 bit half
point pixel formats too. This makes it possible for Wayland EGL clients
to use 64 bit pixel EGL configurations.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/804
Now that cogl understands them, hook wl_shm up so they can be used.
This also bumps the wayland-server version dependency to 1.17.90, which
corresponds to the master branch of wayland. The new formats will be
available in 1.18.0.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/804
Allowing code from inside mutter to create a child process and
delegate on it some of its tasks is something very useful. This can
be done easily with the g_subprocess and g_subprocess_launcher classes
already available in GLib and GObject.
Unfortunately, although the child process can be a graphical program,
currently it is not possible for the inner code to identify the
windows created by the child in a secure manner (this is: being able
to ensure that a malicious program won't be able to trick the inner
code into thinking it is a child process launched by it).
Under X11 this is not a problem because any program has full control
over their windows, but under Wayland it is a different story: a
program can't neither force their window to be kept at the top (like a
docker program does) or at the bottom (like a program for desktop icons
does), nor hide it from the list of windows. This means that it is not
possible for a "classic", non-priviledged program, to fulfill these
tasks, and it can be done only from code inside mutter (like a
gnome-shell extension).
This is a non desirable situation, because an extension runs in the
same main loop than the whole desktop itself, which means that a
complex extension can need to do too much work inside the main loop,
and freeze the whole desktop for too much time. Also, it is important
to note that javascript doesn't have access to fork(), or threads,
which means that, at most, all the parallel computing that can do is
those available in the _async calls in GLib/GObject.
Also, having to create an extension for any priviledged graphical
element is an stopper for a lot of programmers who already know
GTK+ but doesn't know Clutter.
This patch wants to offer a solution to this problem, by offering a
new class that allows to launch a trusted child process from inside
mutter, and make it to use an specific UNIX socket to communicate
with the compositor. It also allows to check whether an specific
MetaWindow was created by one of this trusted child processes or not.
This allows to create extensions that launch a child process, and
when that process creates a window, the extension can confirm in a
secure way that the window really belongs to that process
launched by it, so it can give to that window "superpowers" like
being kept at the bottom of the desktop, not being listed in the
list of windows or shown in the Activities panel... Also, in future
versions, it could easily implement protocol extensions that only
could be used by these trusted child processes.
Several examples of the usefulness of this are that, with it, it
is possible to write programs that implements:
- desktop icons
- a dock
- a top or bottom bar
...
all in a secure manner, avoiding insecure programs to do the same.
In fact, even if the same code is launched manually, it won't have
those privileges, only the specific process launched from inside
mutter.
Since this is only needed under Wayland, it won't work under X11.
Fixes https://gitlab.gnome.org/GNOME/mutter/issues/741
Replace the default master clock with multiple frame clocks, each
driving its own stage view. As each stage view represents one CRTC, this
means we draw each CRTC with its own designated frame clock,
disconnected from all the others.
For example this means we when using the native backend will never need
to wait for one monitor to vsync before painting another, so e.g. having
a 144 Hz monitor next to a 60 Hz monitor, things including both Wayland
and X11 applications and shell UI will be able to render at the
corresponding monitor refresh rate.
This also changes a warning about missed frames when sending
_NETWM_FRAME_TIMINGS messages to a debug log entry, as it's expected
that we'll start missing frames e.g. when a X11 window (via Xwayland) is
exclusively within a stage view that was not painted, while another one
was, still increasing the global frame clock.
Addititonally, this also requires the X11 window actor to schedule
timeouts for _NET_WM_FRAME_DRAWN/_NET_WM_FRAME_TIMINGS event emitting,
if the actor wasn't on any stage views, as now we'll only get the frame
callbacks on actors when they actually were painted, while in the past,
we'd invoke that vfunc when anything was painted.
Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/903
Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/3https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1285
Instead of going via MetaCompositor to know about when we updated
(confusingly named post-paint), use the new stage signal directly.
Note that this doesn't change the time frame callbacks are dispatched;
it's still not tied to actual painting even though it seemed so before
given the function names.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1285
Event delivery with grabbing popups stay essentially the same within
the grabbing client, we still must honor the implicit grab as long as
there is one.
This is however not the case, the popup_grab_focus() function ignores
the button state. The popup_grab_button() function will already indirectly
re-sync the focus surface after the last button is released, so checking
for button state in popup_grab_focus() is sufficient to make the implicit
grab honored with popup grabs involved.
Fixes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1275https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1270
Make the clutter_input_device_get_actor() API public and remove
clutter_input_device_get_pointer_actor() in favour of the new function.
This allows also getting the "pointer" actor for a given touch sequence,
not only for real pointer input devices like mice.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1275
Move Wayland support (i.e. the MetaWaylandCompositor object) made to be
part of the backend. This is due to the fact that it is needed by the
backend initialization, e.g. the Wayland EGLDisplay server support.
The backend is changed to be more involved in Wayland and clutter
initialization, so that the parts needed for clutter initialization
happens before clutter itself initialization happens, and the rest
happens after. This simplifies the setup a bit, as clutter and Wayland
init now happens as part of the backend initialization.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1218
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
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/1141https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1235
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
A DMA buffer might not be able to scanout, and in that case the import
with GBM_BO_USE_SCANOUT will fail. Handle that by failing to scanout,
effectively falling back to compositing.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1261
The shell uses the PID of windows to map them to apps or to find out
which window/app triggered a dialog. It currently fails to do that in
some situations on Wayland, because meta_window_get_pid() only returns a
valid PID for x11 clients.
So use the client PID instead of the X11-exclusive _NET_WM_PID property
to find out the PID of the process that started the window. We can do
that by simply renaming the already existing
meta_window_get_client_pid() API to meta_window_get_pid() and moving
the old API providing the _NET_WM_PID to meta_window_get_netwm_pid().
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1180
Since we're now connecting to one more signal of MetaWaylandOutput, keep
signal connections in one place and move connecting the
"output-destroyed" signal to surface_entered_output() and disconnecting
it to surface_left_output().
This also allows us to use the "outputs_to_destroy_notify_id" as a
simple set and rename it to "outputs".
While at it, also use g_hash_table_destroy() instead of
g_hash_table_unref() since destroy is more clear than unref and does the
same thing in this case.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1230
When hotplugging a new monitor, we recreate all the MetaWaylandOutputs
and need to emit leave events to the surfaces for the old wl_outputs and
enter events for the newly created ones.
There's a race condition though: We might update the monitors a surface
is on (and thus emit enter/leave events for the wl_outputs) before the
Wayland client is registered with the new wl_output (ie. the
bind_output() callback of MetaWaylandOutput was called), which means we
don't send an enter event to the client in surface_entered_output().
Since MetaWaylandSurface now has the MetaWaylandOutput in its outputs
hashtable, it thinks the client has been notified and won't send any
more enter events.
To fix that, make MetaWaylandOutput emit a new signal "output-bound"
when a client bound to the output and make all surfaces which are on
that output listen to the signal. In the signal handler compare the
newly added client to the client the surface belongs to, and if it's the
same one, send an enter event to that client.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1230
The "output-destroyed" signal is used for notifying MetaWaylandSurfaces
that an output they are shown just got invalid (for example because a
monitor hotplug happened).
While we delay the destroying of outputs by 10 seconds since commit
1923db97 because of a race-condition, it doesn't make sense to wait 10
seconds until we let surfaces know that an output was destroyed.
So move the emission of the "output-destroyed" signal to
make_output_inert(), which is called before we start the 10 seconds
delay.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1230
Instead of having everything clumped at MetaWaylandDataManager,
split the primary selection to its own struct. This manager is
handled separately from wl_data_device_manager and other selection
managers, so they would be able to interoperate between them, even.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1193
This is still an openly defined struct, as we will need accessed
by "subclasses". Same principle applies than with the
MetaWaylandDataSource refactor, this is not meant to introduce
functional changes, so just go with it.
On the bright side, the interactions are now clearer, so it could
be made saner in the future.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1193
The split wasn't 100% clean, and some extra private API had to be
added for it (but well, looking at the API, it's already evident
there's a cleanup/streamlining task due). This is meant to be a
refactor with no functional changes, so just go with it.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1193
We already have a signal callback that translates selection ownership changes to
data_device/primary .selection events. Given both will be run when a data source
is being replaced, and this event emission being deleted is kinda short sighted
in that in only knows about Wayland, rely entirely on MetaSelection::owner-changed
emission.
Fixes spurious .selection(null) events being sent when a compositor-local source
takes over the selection without the focus changing (eg. screenshot to clipboard).
Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1160https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1204
We are meant to send a .cancelled event after the drop is performed
in certain situations, but only for version>3 clients. Since this is
all version 3 business, only set the drop_performed flag for v3
clients. This drops the need to perform version checks at the time
of cancelling (which is present for other usecases in v1).
Fixes emission of wl_data_source.cancelled for v1 clients.
Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1177https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1203
This will check whether the current backing buffer is compatible with
the primary plane of the passed CoglOnscreen. Since this will extend the
time before a buffer is released, the MetaWaylandBufferRef is swapped
and orphaned if a new buffer is committed before the previous one was
released. It'll eventually be released, usually by the next page flip
callback.
Currently implemented for EGLImage and DMA-BUF buffer types.
https://gitlab.gnome.org/GNOME/mutter/merge_requests/798
