Simulate two root windows on single monitor with use of RANDR extension

6

This question might seen similar to Emulating extra displays but it's different in the important detail.

Suppose I'd like to test a feature for certain window manager with multi monitor support using RANDR extension. Seems like it is impossible to achieve this using Xrandr/Xdmx. I've tried different combinations with +extension RANDR and +xinerama parameters both to Xrandr and Xdmx but without luck so far. Also, I didn't find any clue in man pages for both commands.

My simple case is:

Xephyr -screen 800x800+0+0 -ac :1 & sleep 1 Xephyr -screen 800x800+800+0 -ac :2 & sleep 1 Xdmx +extension RANDR -xinput local -display :1 -display :2 -ac :3 & sleep 1 DISPLAY=:3 window-manager

I've also tried to simply use only Xephyr:

Xephyr +extension RANDR -screen 800x800+0+0 -screen 800x800+800+0 -ac :3 & sleep 1 DISPLAY=:3 window-manager

but obviously it creates two separate X screens, so the root window is not shared between the screens.

Is there any other way for getting xrandr to report two available outputs with my case?

gryf

Posted 2017-02-16T16:22:27.933

Reputation: 61

You have tried +xinerama and +extension RANDR together? Obviously you need both. If that doesn't work, I'd look at the source and figure out why it doesn't work. – dirkt – 2017-02-17T07:59:47.860

I've tried all of the combination. It is always possibility, that common root window for separate screens simply doesn't work or is not possible with Xrandr/Xdmx for providing more than one RANDR output. – gryf – 2017-02-18T16:57:41.313

No answers