The main motivation behind this change is to prepare input abstractions
for virtual input devices so the wl_seat can properly advertise caps or
the cursor getting properly mapped/unmapped when a fake pointer is
added/removed on a system without a hardware mouse connected.
With this, there are three abstractions - InputDevice, InputBackend, and
InputRedirection.
An InputDevice represents an input device such as a mouse, a keyboard, a
tablet, etc. The InputBackend class notifies the InputRedirection about
(dis-)connected devices. The InputRedirection manages the input devices.
Such design allows to unify the event flow for real and virtual input
devices.
There can be several input backends active. For example, the libinput
backend and an input backend that provides virtual input devices, e.g.
libeis or org_kde_kwin_fake_input.
At the moment, the session code is far from being extensible. If we
decide to add support for libseatd, it will be a challenging task with
the current design of session management code. The goal of this
refactoring is to fix that.
Another motivation behind this change is to prepare session related code
for upstreaming to kwayland-server where it belongs.
Prevent KWin from synchronously autostarting kactivitymanagerd. Indeed,
kactivitymanagerd being a QApplication it will depend on KWin
startup... this is unsatisfactory dependency wise, and it turns out
that it leads to a deadlock in the Wayland case
Once in a while, we receive complaints from other fellow KDE developers
about the file organization of kwin. This change addresses some of those
complaints by moving all of source code in a separate directory, src/,
thus making the project structure more traditional. Things such as tests
are kept in their own toplevel directories.
This change may wreak havoc on merge requests that add new files to kwin,
but if a patch modifies an already existing file, git should be smart
enough to figure out that the file has been relocated.
We may potentially split the src/ directory further to make navigating
the source code easier, but hopefully this is good enough already.
