Function raycast_any 

pub fn raycast_any(
    mesh: &Mesh,
    bvh: &Bvh,
    ray: &Ray,
    opts: &RayOptions,
) -> Result<Option<RayHit>>

Some hit with opts.min_t <= t <= opts.max_t, or None. It stops at the first hit found, so it suits occlusion tests; which hit it returns is unspecified.

Errors

As for raycast.