How to create Fog of War using blueprints

Hello, I am newer to unreal engine 4 and I’m making a top down survival game, the problem is roofs in houses won’t work because of the top down cam and I don’t want players to see in all rooms or outside while the in the house. I was wondering if anyone knew a way to make a “perspective” or Fog of War feature like in This War of Mine or Project Zombiod where you have to be in the room or looking into the room to see stuff, and rooms your not looking into are black. I would like to know if it’s possbile using blueprints.

Example 1 (TWOM):
https://goo.gl/images/DMbRYb
Example 2 (PZ):
https://goo.gl/images/FEkoTJ