how to make enemy sight With out Light?

hi I’m a newbie on UE4 and I want to make my enemy sight, my game is on android devices so i can’t use light (or maybe I can but don’t know how!) but what I want is like attached image,any help would be appreciated.

i dont know about drawing the cone but a few option do come to mind. first theres the built in ai perception or pawn sensing which is built for this kind of thing but i dont know how it performs for mobile since i dont work with mobile. another option would be to use a cone mesh that only overlaps characters, then on overlap you do a line trace to see if the character is hidden behind something. this ones not too hard to implement but you would have to adjust the script to get it to function just as you like.

Thanks,also i found a great example here and it’s working fine in mobile.