warp.volume\_voxel\_count
=========================

.. function:: warp._src.lang.volume_voxel_count(id: uint64) -> int32

   .. hlist::
      :columns: 8

      * Kernel
      * Python

   Return the number of indexable voxels in the volume given by ``id``.
   
   :func:`~warp.volume_voxel_count` and :func:`~warp.volume_lookup_index` support volumes with at
   most ``2**31 - 1`` indexable voxels. This function is not differentiable.
   
   :param id: The ``id`` of a :class:`warp.Volume`.
   
   :returns: The number of indexable voxels. This is the required size of a per-voxel ``voxel_data``
             array (as used by :func:`~warp.volume_sample_index`) and the exclusive upper bound of
             indices returned by :func:`~warp.volume_lookup_index`.
   
   .. rubric:: Example
   
   .. testcode::
   
       @wp.kernel
       def count(vid: wp.uint64, out: wp.array[wp.int32]):
           out[0] = wp.volume_voxel_count(vid)
   
       voxels = wp.array([[0, 0, 0], [1, 0, 0]], dtype=wp.vec3i)
       volume = wp.Volume.allocate_by_voxels(voxels, voxel_size=1.0)
       out = wp.zeros(1, dtype=wp.int32)
       wp.launch(count, dim=1, inputs=[volume.id], outputs=[out])
       print(int(out.numpy()[0]))
   
   .. testoutput::
   
       2