This is especially useful if the compositor wants to support X11
panels to control windows. Without the signal a compositor does
have to hook into the user_event_handler callback but that would
not change the _NET_SUPPORTED root window property.
The old logic might not update the entire scene node when a node is
disabled. It would only consider the damage last time (the damage was
based on the visible region of the node).
It's important that we update the entire node region because xwayland
stacking will depend on this.
In labwc, we have had trouble with XWayland windows using the Globally
Active input model (see wlr_xwayland_icccm_input_model()). Under
traditional X11, these windows do not expect to be given focus directly
by the window manager; rather, the WM sends them a WM_TAKE_FOCUS message
prompting the client to take focus voluntarily.
Currently, these clients are difficult to support with wlroots, because
wlr_xwayland_surface_activate() assumes the client window will always
accept the keyboard focus after being sent WM_TAKE_FOCUS. Some Globally
Active client windows (e.g. panels/toolbars) don't want to be focused.
It's useless at best to focus them, and might even make them misbehave.
Others do need keyboard focus to be functional -- and there doesn't seem
to be any reliable way to know this in advance.
Adding wlr_xwayland_surface_offer_focus() allows the compositor to send
WM_TAKE_FOCUS to a client window supporting it and then see whether the
client accepts or ignores the offer. If it accepts, the surface will emit
the focus_in signal notifying the compositor that it has received focus.
This is entirely opt-in. A compositor that doesn't want to use the new
function can continue to call wlr_xwayland_surface_activate() directly
just as before.
Currently _NET_WM_STATE is updated in xwm_focus_window() but
_NET_ACTIVE_WINDOW is updated in xwm_surface_activate(). In some cases
(for example, client-initiated focus changes) the two properties can get
out of sync.
Factor out a new function which updates both properties in sync.
Adjust the logic in xwm_handle_focus_in() to call either
xwm_focus_window() or xwm_set_focused_window(), or neither, as
appropriate.
From the event description:
This event indicates that the output power management mode control is no
longer valid. This can happen for a number of reasons, including:
<...>
- The output disappeared
This swaps the argument order of wlr_surface_accepts_touch() and
wlr_surface_accepts_tablet_v2(), putting the wlr_surface argument first
as should be the case for functions namespaced with wlr_surface_*.
We were relying on the fact that we wouldn't paint anything on top
of the black background in the region of a black rect. However
when fractional scaling is used the repaint region might get
expanded to nearby pixels by scale_output_damage(). As a result
the neighbour scene nodes might leak into the skipped black rect's
region.
Avoid this by using this optimization for bottom-most black rects
only when fractional scaling is used.
References: https://github.com/swaywm/sway/issues/8233
