xfwm: struts + multi monitor - does that work ?

[killermoehre at gmx.net]

> Am 02.11.2022 um 18:04 schrieb Enrico Weigelt, metux IT consult <lkml at metux.net>:
> 
> Hello folks,
> 
> 
> just looking at the geometry constraints code (that's also checking for
> struts) and wonder whether that works at all - the implementation
> doesn't care about monitors at all.
> 
> The netwm spec is a bit misleading at this point - since it predates the
> Xinerama, it can't know about Xscreens spanning multiple monitors.
> It says struts are in root window coordinates.
> 
> KWin seems to interpret the spec differently, assuming struts are
> relative to monitors.
> 
> What can we do about that ?
> 
> 
> —mtx
Hi Enrico,

actually, the standard does know about Xinerama [1].

----8<———— 
The start and end values associated with each strut allow areas to be reserved which do not span the entire width or height of the screen. Struts MUST be specified in root window coordinates, that is, they are not relative to the edges of any view port or Xinerama monitor.
————>8————

If KWin is doing this per monitor, than it is actually misreading the spec.

BR
Silvio

[1] https://specifications.freedesktop.org/wm-spec/wm-spec-latest.html#idm46409506252832