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I would like to be able to emulate a dual monitor set up using a single physical display. Ideally, X11 would be able to treat each left/right half of the monitor as a separate display. Is this possible with X11?


I've cobbled together some crude images to attempt to better clarify what my intent is.

Imagine the following dual monitor set up:

enter image description here

Since I only have a single, large, widescreen monitor, I would like X11 to believe that the single physical display is actually two displays; each taking up a horizontal half of the physical display space, as follows:

enter image description here

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No, but with xnest and tiling WM you can do something like that. – Eddy_Em Feb 11 '13 at 19:40
That depends on what you want to emulate or what you want to do/test/proove with your emulated environment. X has quite some abstraction going on before actual screens become (X-) screens and even more before they become (the visible part of) your working area – Bananguin Feb 11 '13 at 19:52
Let me rephrase: WHY do you want to do that? Usually, X11 creates one unified display out of many physical screens. If you first fake your 1 screen to be actually 2, X will take them and make one out of them. So, what is the actual goal? – Bananguin Feb 11 '13 at 21:47
@user1129682: Most WMs are aware that there are multiple displays present. e.g. a tiling WM wouldn't stretch a single window across both of your monitors. – noffle Feb 12 '13 at 17:18
@noffle: yes, WMs have some special characteristics. They still work on the one X display that X creates, even though they can be aware of the physical screens – Bananguin Feb 12 '13 at 21:01

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