ray_surface

The normal and the corrected end of the closest triangle hits the ray kernel found. Bind the same rays, pts, vpt and vstart the ray dispatch read, and its hit and hit_prim outputs. Outputs, a value per ray: hit_normal (the unit normal of the triangle hit, turned to face the ray's origin side, zero for a miss) and hit_end (the hit point pushed out along the normal by the skin param; for a miss the ray's end, origin + direction * tmax). The shape index of a hit is hit_prim, the primitive. Exact.