I am currently trying to implement a specific directional light type.
This light type has been used in the game INSIDE and is called orthogonal spotlight (aka local directional light). I assume that this is a directional light which behaves like a spot light and have a squared or rectangular attenuation but I have some difficulties to integrate it in my deferred pipeline and get the general concept of this light type.
Implementing a simple directional light is simple
dot(worldNormal, lightDir) but what kind of data should I use to constraint its application into a square or a rectangle ?
I hope that you'll be able to give me some clues. Thanks a lot !