Here is screen off animations mod for Samsung's 4.3 firmware. It was originally made by sorg for S4 and I have ported it to S3. So huge thanks to him for original mod. You can thank him here.
It has 2 animation mods:
U can change this with terminal emulator using setprop command or u can write this line in build.prop file.
persist.sys.screen_off=fade -> for fade effect during screen off persist.sys.screen_off=crt -> for crt effect during screen off persist.sys.screen_off=none -> for no effect(stock)
This mod is for Deodexed Roms only, so don't flash it on Odex Roms
Make a nandroid backup before flashing this mod.
sorg for code