Discussion for Virtual Desktops and Activities future

[Marco Martin]

On Sun, Jul 15, 2018 at 3:57 PM Martin Flöser <mgraesslin at kde.org> wrote:
> Activities are weird and we (Thomas and I) never knew what they are and
> how we should integrate them in KWin. The existing code is just a bad
> copy of virtual desktops (bad because it copied the code 1:1 without
> understanding what it does including the things which just don't make
> sense). It's one of the few areas in KWin which are truly unmaintained.

totally agree on that point, it's a bad copy which needs to go.

> So from KWin perspective I would prefer:
>   * virtual desktops gain support for windows on multiple desktops
it does ;)
>   * activity support gets removed from KWin
>   * any mapping from activity to virtual desktop happens outside of KWin
> (e.g. in kamd)

yeah, i would like too to have the direct support of activities in
kwin gone (even in x11, but won't be possible for a long time i fear)
the way i originally tought about it was:
* kwin manages/saved/reads virtual desktops as now
* kamd uses as a "source" of valid activities the list of kwin desktops
* kamd reacts to desktop change with activity change
* removing a desktop would mean removing an activity
* adding a desktop is adding an activity
* if is kamd to ask to create an activity, it asks to kwin beforehand,
and creates it only if/when kwin anwered with a new desktop id
* if kamd wants to switch activity, asks kwin beforehand

annoying thing, the desktops kwayland protocol would have to have a
pretty much 1:1 identical implementation in dbus (which may be needed
anyways for the desktops kcm...)