Dot product is the thing you are looking for. It equals to 1 (looking directly at the object) to 0 (the object is at 90 degrees to your view). UE4 has an example of this in the math level.
Dot product is the thing you are looking for. It equals to 1 (looking directly at the object) to 0 (the object is at 90 degrees to your view). UE4 has an example of this in the math level.