how to reduce screen or decrese screen brightness become smoothly on linux

hi guys, today i wanna tell you how to reduce screen or decrese screen brightness become smootly on linux. i post this article because since i change my linux using some windows manager and i don't know how to change the brightness. so, i think "mm, what i done. if i change brightness on terminal ? " so i tried to share on some search engine and i found the answer. so, i try and it done. and my screen become reduce smoothly now. its why i wanna share with you..
oke, go to the step now!

1. open your terminal.
2. type xrandr -q | grep " connected"
3. it will gives you the output as eDP1 connected 1366x768+0+0 (normal left inverted right x axis y axis) 309mm x 173mm4. There eDP1 Stands for your display . so now you have to do as type: 
xrandr --output LVDS1 --brightness 0.5

note: there 0.5 stands for brightness and it ranges from 0.0 to 1.0 . 0.0 -> Full black .so you have to choose the required value of brightness .

 oke its done. i hope its can work for you, if success, feedback, and etc please leave command bellow..