Determine the X Display edge in a multi X screen configuration

[Adam Jackson]

On Thu, 2017-10-26 at 19:15 +0300, Evgeny Zubok wrote:
> Adam Jackson <ajax at nwnk.net> writes:
> 
> > Such a function does not exist. As far as the protocol is concerned,
> > screens do not have any relative geometry.
> 
> Can the pointer barriers which were introduced in X Fixes extention
> serve a purpose?

I believe those only generate an event if they actually block the
pointer's motion, and that that's calculated in the coordinate space of
a single screen; warping between screens would not trigger a barrier
because it's as if the pointer left the screen entirely, not that it
moved within some global coordinate space. 

I haven't tried it, so maybe, but if it works I suspect it's a lucky
accident of implementation more than something anyone intentionally
made work. Certainly when I initially wrote barriers I didn't do
anything special with regard to screen crossings.

- ajax