How to determine if the intersection point falls on the emitter

[ioissss]

After getting the scene intersection points via scene.ray_intersect() , how to determine whether these points are located on the emitter or not?

[njroussel]

Hi @ioissss

There's a method in the SurfaceInteraction3f struct for this: https://mitsuba.readthedocs.io/en/latest/src/api_reference.html#mitsuba.SurfaceInteraction3f.emitter2
You can then do mask = dr.eq(emitter, None) to get a boolean mask.

It takes in the scene as a parameter so that it can return the envrionment map if the ray didn't hit any surface.