[PATCH xserver] xwayland: don't use logical size for RRMode

[Simon Ser]

On July 10, 2018 8:44 AM, Olivier Fourdan <fourdan at gmail.com> wrote:
> Yeap, that's what I meant, xdg-output would advertise the logical size
> (i.e. appropriately scaled), so we want to pass RR the values provided
> by xdg-output here, not those from wl_output.
>
> Basically, we do not need to keep or reuse the mode_width/height as
> with your initial patch, we just need to compensate the rotation as
> you said (as for the rationale behind this bug, mutter doesn't use
> rotations, so I didn't notice it).

Right. Just sent another patch which does that. I just thought it was weird to
use the logical size for the mode, but it makes sense since X11 doesn't
support scaling.

> [unrelated, as an aside, it looks like in your example, the compositor
> might not be sending the geometry, so we end up with 0 in the physical
> size]

Yes, that's intentional. When the physical size isn't available (e.g. when using
projectors or virtual outputs) we just send zero. Do you think this is harmful?
I like sending zero because it clearly says "this piece of information is not
relevant in the current situation" instead of faking data. Maybe Xwayland should
fake it and use a default 96 DPI in this case?

I'm not aware of any X11 client that breaks because of this (yet).

> Cheers,
> Olivier