How can I mirror/flip display output?

After testing on 2 PCs, I found the following:

On some integrated cards like Intel you can use xrandr in console. For example:

Go to console (Ctrl+Alt+T)

• xrandr -x will flip de video horizontally like a mirror.
• xrandr -y will flip de video vertically.
• xrandr -y -x will flip both.
• xrandr -o normal will return to normal the video.
• xrandr -o inverted will...invert O.o

But if you have an Nvidia this may not work. For an Nvidia to work you need to:

1. Edit you xorg.conf: sudo nano /etc/X11/xorg.conf

2. Find the section that has Driver "nvidia" in it

3. Copy and paste the following at the end of that section: Option "RandRRotation" "on"

This will activate the rotation for Nvidia which comes off by default. Why off by default i do not know.

After that reboot and you can change the orientation BUT NOT the reflection. What i mean with this is that Nvidia does not yet support reflection options like -x or -y options in xrandr. I will keep searching for some more since the question is interesting.