These are now referenced on the frames client side (in order to
track deletable state from the client window) and the mutter side
(pretty much everything else, like figuring out if a window wants
WM decorations).
It makes sense to make this a separate header, so that we don't
need to doubly define these flags/structs.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2735>
We use this for tracking the deletable state of the client window,
but forgot to check that the MWM_HINT_FUNCTIONS hint is set in
hints.flags before checking hints.functions.
This resulted in windows that do not specify this flag (and thus
should go with the defaults) in being mistakenly removed the close
button, as the functions flags would be typically 0 in that case.
Fixes issues with Chromium and Electron applications missing the
close button, since Chromium does this on X11.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2735>
Recalculating window features is a busy thing on the Mutter side, the
different properties being (re)set will overwrite the current state
and cause some side work. Between that is the rewriting of the
_MUTTER_NEEDS_FRAME property on the window being recalculated, which
throws the frames client off, by thinking the window does actually
require a new frame.
It is not sufficient to trust that PropertyNewValue means the property
or the value are new, also double check that the window did not have
in fact a frame, and avoid the busy work if it did.
Besides the busywork that can be easily avoided, this also fixes the
window close button state being stuck if the window changed its
deletable state, since the frame being respawn managed to miss the
property change.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2735>
There's two meanings of "frame" there! Since SSD frames are now
rendered by an external client, and there are no actual mechanism
that ensures the frame did already get painted when the client did
respond to its NET_WM_FRAME_SYNC_REQUEST request, there may be
artifacts when resizing windows.
In order to get always the best visual result, we should actually
synchronize rendering with both the client window and the window
frame window.
This commit adds these mechanisms, so a sync alarm update is
expected on both windows until further resizes are allowed, this
ensures window and frame stay in sync, even after moving rendering
elsewhere.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2175>
This small X11 client takes care of creating frames for client
windows, Mutter will use this client to delegate window frame
rendering and event handling.
The MetaWindowTracker object will keep track of windows created
from other clients, and will await for _MUTTER_NEEDS_FRAME property
updates on those (coming from Mutter), indicating the need for a
frame window.
This process is resilient to restarts of the frames client, existing
windows will be queried during start, and the existence of relevant
properties checked. Mutter will be able to just hide/show
SSD-decorated windows while the frames client restarts.
The frames are created through GTK4 widgets, the MetaWindowContent
widget acts as a replacement prop for the actual client window,
and the MetaFrameHeader wraps GtkHeaderBar so that windows can be
overshrunk, but otherwise a MetaFrame is a 100% true GTK4 GtkWindow.
After a frame window is created for a client window, the
_MUTTER_FRAME_FOR property will be set on the frame window,
indicating to mutter the correspondence between both Windows.
Additionally, the pixel sizes of the visible left/right/top/bottom
borders of the frame will be set through the _MUTTER_FRAME_EXTENTS
property, set on the frame window.
In order to make the frame window behave as the frame for the
client window, a number of properties will be tracked from the
client window to update the relevant frame behavior (window title,
resizability, availability of actions...), and also some forwarding
of events happening in the frame will be forwarded to the client
window (mainly, WM_DELETE_WINDOW when the close button is clicked).
Other than that, the frames are pretty much CSD GTK4 windows, so
window drags and resizes, and window context menus are forwarded for
the WM to handle.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2175>
