warp.bvh\_get\_group\_root
==========================

.. function:: warp._src.lang.bvh_get_group_root(id: uint64, group: int32) -> int

   .. hlist::
      :columns: 8

      * Kernel

   Get the root of a group in a BVH.
   
   :param id: The BVH identifier
   :param group: The group identifier
   
   :returns:
   
             The root node index for the specified group. If the group does not exist, returns ``-1``
                 (sentinel for the BVH global root). Pass ``-1`` to BVH queries to traverse from the global root.