A colleague of mine mentioned that mantra using the forward raytracing technique to render by shooting a lot of “imaginary” rays.

I'd ask if we can control the ways the “imaginary” rays are shot.

e.g. can we somehow use mantra to calculate how much sky a point on surface can see vs the entire sky if it's more efficient?
(we've already done this using SOPs or VEX)

Pls advise if I understand it wrongly.

Thanks!

- Ji