for the record I would like to attach a transcript from today's UBports chat [ENGLISH]
Don Fredl, [26.02.25 11:34]
the only thing I can tell is that Mir and QtMir are not negotiating geometry changes based on orientation yet
Don Fredl, [26.02.25 11:35]
but I am unsure as to how that is supposed to happen (maybe @alan_griffiths knows something)
Don Fredl, [26.02.25 11:35]
since we want to avoid resolution changes
Don Fredl, [26.02.25 11:38]
I will give my Laptop running Mir 2.x a shot later and see if something has changed
Don Fredl, [26.02.25 11:38]
this thing can rotate
Alan, [26.02.25 11:44]
No more than you've stated. When Mir handles both input and compositing everything is consistent: Other Mir based compositors like Frame, Miriway and Miracle-WM work fine.
But QtMir takes over both input and compositing and routes everything through the Qt compositor. There things are inconsistent. I have not looked, but it sounds as though Mir isn't informed about the rotation and therefore constraints input to the the output it thinks is there.
Don Fredl, [26.02.25 11:44]
could you point me to the place where it applies those constraints?
Don Fredl, [26.02.25 11:45]
in Mir that is
Alan, [26.02.25 11:59]
Not somethin I know well, but SeatInputDeviceTracker::confine* looks likely
Don Fredl, [26.02.25 12:00]
Thanks, will take a look when I can
TheKit, [26.02.25 16:19]
that sounds about right to me. I've checked that previously and another issue is that due to the mentioned above XWayland isn't getting screen size updated when the display is rotated
TheKit, [26.02.25 16:20]
and X11 calculates scaled relative input coordinates based on the screen size, so the touches in rotated mode end up out of range
TheKit, [26.02.25 16:26]
what we need to figure out is the way to handle screen rotation so Lomiri can still do the animation when it's changed, but let the Mir server be aware of the updated geometry
Alan, [26.02.25 18:50]
It shouldn't be hard (unless input is handled during rotation - and that is madness). Mir has an internal notification system for display changes and that just needs to be fed the new layout.
TheKit, [26.02.25 19:16]
One thing that makes me wonder. Which component handles the actual content rotation? Is it done in software in QML renderer?
