In order to correctly fix the issue to make sure we only set the
focused surface to NULL during a grab, but not the current surface,
we need to merge update_current_surface back into repick_for_event
so we have more control over the behavior here.
... not when we do an update.
We only repick when we handle events, not when we update. Perhaps
this is a mistake.
Since update runs before handle_event, this means that when we
drop a grab, update will notice the NULL surface, since we haven't
repicked after the event, and then we'll repick the correct surface.
The end result is that you see a root cursor after a grab ends,
rather than the correct window cursor.
This doesn't fix it, since the current surface becomes NULL when
we start the grab. But it does make the code here more correct when
we fix that bug.
I was talking with other people and they became confused at the
term "double-buffered", since we were also talking about
double-buffering in general, e.g. swapping between two buffers.
Instead, we'll adapt the "pending state" nomenclature that we
already use for the field / variable names.
If we have a focused surface, we need to eat up key events, not
just if we have a non-empty focus resource list. The latter would
happen if we have a focused client but it never called get_keyboard.
The latest Xorg / Xwayland has support for -displayfd being used
in conjunction with an explicit display number. Use that to know
when the X server is ready, rather than UNIX signals, because
they're UNIX signals.
If we're sending out a configure event, we can't immediately move the
window; we need to instead wait to apply the new position when the
client sends a new buffer.
dx/dy should be against the regular window's rect, and need to
be ignored when we're resizing. Instead, we use gravity to anchor
the window's new rectangle when resizing.
Sophisticated clients, like those using ClutterGtk, will have more
than one focused resource per client, as both Clutter and GDK will
ask for a wl_pointer / wl_keyboard. Support this naturally using
the same "hack" as Weston: multiple resource lists, where we move
elements from one to the other.
In order to support multiple pointers for the same client, we're
going to need to kill it.
This will cause crashes for now, but will be fixed by the next
commit.