How to duplicate desktop in Linux with xrandr

deepindisplayxrandr

Currently, I'm using Deepin OS 15.4.

By default Deepin sets the desktop to extended mode when a projector is connected, but what I want is to duplicate my screen.

I can't find it in the Control Center configuration, but I stumbled upon in this question.

The above extends the monitor with xrandr,

How do I duplicate my desktop to the projector with xrandr?

Best Answer

First find out the name of each display e.g. using xrandr --current. Then the following command should work to duplicate them.

 $ xrandr --output <projector> --same-as <desktop>

Related Solutions

How to modify the default setting adopted by xrandr when connecting an external monitor

I don't know exactly how to write a default setting for xrandr when you connect an external monitor, but you can easily write a custom script and then associate it to a shortcut key, such as meta + P.

Example

> nano  /usr/bin/custom-xrandr
#!/bin/bash
xrandr --output VGA1 --off --output HDMI1 --auto

> chmod u+x /usr/bin/custom-xrandr

Then associate some shortcut to /usr/bin/custom-xrandr and every time you connect an external monitor just press that keys.

This should achieve exactly what you want.

Reset xrandr (or: switch off the –scale-from setting at disconnect)

I use this same workflow and stumbled on a solution today. It looks like --scale and --scale-from are convenience aliases for --transform so I think the best way to "reset" these kinds of modifications is by using the flag below:

--transform none