bug#22549: 25.0.50; Tooltips placed outside of screen limits

[martin rudalics]

> I think I know what is happening.
>
> I have two monitors, side by side, simulating a continuous display.

I expected something like that.

> The
> monitor on the left side, where Emacs is displayed, has a vertical
> resolution of 1050 pixels while the monitor on the right side has a
> vertical resolution of 1200 points. Emacs is using the vertical
> resolution of the virtual display (the largest of the two monitors, i.e.
> 1200 points) instead of the resolution of the monitor that hosts the
> Emacs frame.

Did you check via ‘x-display-pixel-width’ and ‘x-display-pixel-height’
and the selected frame on either of your monitors?

And what does ‘x-display-monitor-attributes-list’ return?

> Something similar happens for the horizontal overflow: the dimensions of
> the virtual desktop are used instead of the dimensions of the monitor.
>
> I've seen similar issues on the past for other applications, and they
> were fixed, eventually. The key here is that, while the two monitors
> belong to a single desktop, it can't be considered a continuous surface.
> For instance: the window manager never gives to a window a default
> position that makes it overlap over the two monitors, unless the window
> is so big that doesn't fit on one monitor. Ditto for maximizing: windows
> maximize on one monitor, not on the whole virtual desktop (Emacs does
> this right, so it already knows how to query the resolution of the
> current monitor.)

It's the window manager that maximizes the frame and tells Emacs the
required coordinates so no querying should occur here.

martin