UE4 Lighting, well worth a watch, this was on Unreal Spot Light Projects the other day. https://www.youtube.com/watch?v=grN5Yd55UIM https://www.youtube.com/watch?v=fpX22bc_NiU https://www.youtube.com/watch?v=WTd6OgXQ4RY https://www.youtube.com/watch?v=mzGnRbcynpc