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To invert the entire screen you can use the program
xcalib
:xcalib -invert -alter
From the xcalib man page
xcalib loads 'vcgt'-tag of ICC profiles to the X-server using the XVidMode Extension in order to calibrate your display.
That means it does not depend on compiz being used.
You can install it using
sudo apt-get install xcalib
. To make it more convenient assign a keyboard shortcut opening the Keyboard
settings.![Keyboard Settings for adding manual shortcut](http://i.stack.imgur.com/quYka.png)
There, navigate to shortcuts. Add a custom shortcut by pressing the plus button, add the name and the command. It will be disabled by default, so assign a shortcut by clicking on
Disabled
and perform the wanted shortcut, e.g. meta + iBefore:
![before](http://i.stack.imgur.com/ENYb9.png)
After
xcalib -invert -alter
was launched (mapped to <meta-i>
:![after](http://i.stack.imgur.com/FxppP.png)
Pressing it again restores to the normal not inverted screen.