public LinkedList < TileModel > getTiles () {
        if ( tilesList == null ) {
            tilesList = new LinkedList < TileModel > ();
            for ( int i = 0; i < tiles.length; i++ ) {
                if ( tiles [ i ] != null ) {
                    for ( int j = 0; j < tiles [ i ].length; j++ ) {
                        if ( tiles [ i ] [ j ] != null )
                            tilesList.add ( tiles [ i ] [ j ] );
                    }
                }
            }
        }

        return tilesList;
    }