public PlayablePuzzleSquareContentsCell(PlayablePuzzle parent, IVar <Square> contents, Vector2D position)
     : base(contents.Value)
 {
     this.parent   = parent;
     this.contents = contents;
     this.position = position;
 }
 public PlayablePuzzleSquare(PlayablePuzzle parent, IVar <Square> contents, Vector2D position)
 {
     this.Contents = new PlayablePuzzleSquareContentsCell(parent, contents, position);
     this.Position = position;
 }