Why not use unit_directions in _custom_xy_to_ray_bundle

[fisheatmice]

in the code of utils/ray_utils.py

        ray_bundle = _custom_xy_to_ray_bundle(
            cameras, 
            xy_grid, 
            rays_zs=rays_zs, 
            n_pts_per_ray=n_pts_per_ray,
            unit_directions=self._unit_directions, #false
        )

why not use unit_directions = True,
if do that , it seems reference_depth and query_depths are same value

what is the purpose of it