Occludes light cast by a Light2D, casting shadows. Occludes light cast by a Light2D, casting shadows. The LightOccluder2D must be provided with an [OccluderPolygon2D] in order for the shadow to be computed. The LightOccluder2D's light mask. The LightOccluder2D will cast shadows only from Light2D(s) that have the same light mask(s). The [OccluderPolygon2D] used to compute the shadow.