CUTMESHBYPLANE Cut a mesh by a plane.

   [ABOVE, IN, BELOW] = cutMeshByPlane(MESH, PLANE)
   where MESH, ABOVE, IN, BELOW are structs with the fields vertices and
   faces, and PLANE is given as a row containing initial point and 2
   direction vectors. ABOVE, IN, BELOW contain the corresponding parts of
   the input mesh.

   [ABOVE_V, ABOVE_F, IN_V, IN_F, BELOW_V,BELOW_F] = ...
       cutMeshByPlane(V, F, PLANE) where V is a [NVx3] array containing
   coordinates and F is a [NFx3] array containing indices of vertices of
   the triangular faces.

   BELOW = cutMeshByPlane(V, F, PLANE, 'part', 'below') BELOW is a struct
   with the fields vertices and faces. Other options are:
       'part'  -   'above': Faces above the plane
               -   'in'   : Faces in the plane
               -   'below': Faces below the plane

   [BELOW_V, BELOW_F] = cutMeshByPlane(MESH, PLANE, 'part', 'below') is
   possible, too.

Package: matgeom