warp.mesh\_query\_next
======================

.. function:: warp._src.lang.mesh_query_next(query: MeshQueryAABB, index: int32) -> bool

   .. hlist::
      :columns: 8

      * Kernel

   Advance a mesh query to the next matching triangle and report whether one was found.
   
   Writes the face index of the current result to ``index`` and returns ``True``; returns
   ``False`` once no more results remain (``index`` is then left unchanged). The reported index
   is a 0-based face index into the mesh's triangles, suitable for :func:`mesh_eval_position`,
   :func:`mesh_eval_face_normal`, and the other face-indexed functions.
   
   What counts as a *match* depends on the query type:
   
   - :func:`mesh_query_aabb`: triangles whose bounding box overlaps the query box.
   - :func:`mesh_query_sphere`: triangles whose closest point to the sphere center is within the radius.
   
   :param query: The query to advance, from :func:`mesh_query_aabb` or :func:`mesh_query_sphere`
   :param index: Output; receives the face index of the current result
   
   :returns: ``True`` if another matching triangle was found (its face index written to ``index``),
             ``False`` if the query is exhausted.
   
   .. rubric:: Example
   
   .. testcode::
   
       @wp.kernel
       def count_faces(mesh_id: wp.uint64, lo: wp.vec3, hi: wp.vec3, out_count: wp.array[wp.int32]):
           query = wp.mesh_query_aabb(mesh_id, lo, hi)
           face = int(0)
           while wp.mesh_query_next(query, face):
               wp.atomic_add(out_count, 0, 1)
   
       points = wp.array([[0,0,0],[1,0,0],[1,1,0],[0,1,0],[0,0,1],[1,0,1],[1,1,1],[0,1,1]], dtype=wp.vec3)
       indices = wp.array([0,3,2, 0,2,1,  4,5,6, 4,6,7,  0,1,5, 0,5,4,
                           2,3,7, 2,7,6,  0,4,7, 0,7,3,  1,2,6, 1,6,5], dtype=wp.int32)
       mesh = wp.Mesh(points=points, indices=indices)
   
       out_count = wp.zeros(1, dtype=wp.int32)
       wp.launch(count_faces, dim=1, inputs=[mesh.id, wp.vec3(-1.0, -1.0, -1.0), wp.vec3(2.0, 2.0, 2.0)], outputs=[out_count])
       print("overlapping faces:", out_count.numpy()[0])
   
   .. testoutput::
   
       overlapping faces: 12
   

.. function:: warp._src.lang.mesh_query_next(query: _MeshQuerySphere, index: int32) -> bool
   :noindex:

   .. hlist::
      :columns: 8

      * Kernel

   Advance a sphere mesh query to the next matching triangle.
   
   Overload for queries created by :func:`mesh_query_sphere`.

.. function:: warp._src.lang.mesh_query_next(query: MeshQuery, index: int32) -> bool
   :noindex:

   .. hlist::
      :columns: 8

      * Kernel

   Advance a mesh query whose kind is selected at runtime to the next matching triangle.