Change the screen brightness using bash script - xrandr

In my Ubuntu 14.0 (Dell Inspiron), brightness controls were not working at all. So I started searching for other alternatives to sets the brightness.

finally I found this xrandr.
it is great tool to set the brightness and even to rotate the screen.

--brightness flag can be used to set the brightness (best values: 0 - 1)

--brightness flag cab be used to rotate the screen (possible options : normal, left, right) 

Usage:
          ./brightness_control.sh +      # Increase the brightness by 0.05
          ./brightness_control.sh  -       # Decrease the brightness by 0.05
          ./brightness_control.sh 1       # Set brightness to 1
 
 

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