Dual-head kiosk/embedded application

[Nicolas Jeker]

On Thu, 2020-08-06 at 13:45 +0300, Pekka Paalanen wrote:
> On Thu, 06 Aug 2020 09:35:15 +0000
> Simon Ser <contact at emersion.fr> wrote:
>
> > Hi,
> >
> > On Thursday, August 6, 2020 9:02 AM, Nicolas Jeker <n.jeker at gmx.net
> > > wrote:
> >
> > > I'm currently working on a solution to run two instances of a
> > > full
> > > screen application on separate screens with separate touch screen
> > > input. This is pretty easy if the application has Wayland support
> > > by
> > > using a pair of wl_seats, one for each output and touch screen.
> > > Multi-
> > > seat with X11 on a single graphics card is as far as I understand
> > > impossible.
> >
> > I don't quite understand why multiple seats are necessary here.
> > Isn't
> > it possible to map touch screen input A to output A and touch
> > screen
> > input B to output B?
>
> Maybe there is a confusion in terminology. To clarify:
>
> Multi-seat is not multiple wl_seats in the same compositor instance.
> Multi-seat means a compositor instance per each seat such that each
> seat has a different user (account).
>
> I don't think there is a canonical word to describe the multiple
> wl_seats in the same compositor instance case. Multi-focus perhaps?
>
> Nicolas, do you want actual multi-seat (user separation), or just
> multi-focus to have each touchscreen deliver input independently of
> each other?

For my use case multi-focus is exactly what I need, that's why I
suggested using multiple wl_seats on Wayland, which is what I'm doing
at the moment. On X11 this is not possible without using full blown
multi-seat if I'm not mistaken. From the perspective of the user it
should feel like using two separate devices.

> Both touchscreens cannot be in the same wl_seat in the same
> compositor
> instance if they are to operate independently e.g. by two different
> people.
>
> Well done homework, by the way. :-)

Thanks!