[meaytvry] Tactile cube maze

A cube has a button on each face, and virtually represents a location in a cubical maze.  A button may be pushed if travel is possible in that direction.  Perhaps the button pushes out to indicate it is pushable, or retracts if it is not.

But we would prefer somehow to give the user one-ply lookahead, communicating what the available directions would be if a certain direction is taken.  This would be easy to do for a two-dimensional maze.