Building Ghosts:

• Add ghost elements layer-by-layer from init

• A chunk will include ghosts of all the elements it is connected to by “tuples”—sets of nodes

• For 2D, a tuple might be a 2-node edge

• For 3D, a tuple might be a 4-node face

• You specify a ghost layer with FEM_Add_ghost_layer(tupleSize,ghostNodes)

• ghostNodes indicates whether to add ghost nodes as well as ghost elements.