// check left of rook
        for (int x = 1; x < Position.x; x++)
        {
            Position dir = new Position(Position.x - x, Position.y);

            if (Board.Pieces[dir] is not null)
                break;

            validMoves.Add(dir);
        }

        // check right of rook
        for (int x = 1; x < Board.Width - Position.x; x++)
        {
            Position dir = new Position(Position.x + x, Position.y);

            if (Board.Pieces[dir] is not null)
                break;

            validMoves.Add(dir);
        }

        // check top of rook
        for (int y = 1; y < Position.y; y++)
        {
            Position dir = new Position(Position.x, Position.y - y);

            if (Board.Pieces[dir] is not null)
                break;

            validMoves.Add(dir);
        }

        // check top of rook
        for (int y = 1; y < Board.Height - Position.y; y++)
        {
            Position dir = new Position(Position.x, Position.y + y);

            if (Board.Pieces[dir] is not null)
                break;

            validMoves.Add(dir);
        }

        // check left of rook
        for (int x = 1; x < Position.x; x++)
        {
            Position dir = new Position(Position.x - x, Position.y);

            if (Board.Pieces[dir] is not null)
                break;

            validMoves.Add(dir);
        }

        // check right of rook
        for (int x = 1; x < Board.Width - Position.x; x++)
        {
            Position dir = new Position(Position.x + x, Position.y);

            if (Board.Pieces[dir] is not null)
                break;

            validMoves.Add(dir);
        }

        // check top of rook
        for (int y = 1; y < Position.y; y++)
        {
            Position dir = new Position(Position.x, Position.y - y);

            if (Board.Pieces[dir] is not null)
                break;

            validMoves.Add(dir);
        }

        // check top of rook
        for (int y = 1; y < Board.Height - Position.y; y++)
        {
            Position dir = new Position(Position.x, Position.y + y);

            if (Board.Pieces[dir] is not null)
                break;

            validMoves.Add(dir);
        }

        // check left of rook
        for (int x = 0; x < Position.x; x++)
        {
            Position dir = new Position(Position.x - x, Position.y);

            if (Board.Pieces[dir] != null)
                break;

            validMoves.Add(dir);
        }

        // check right of rook
        for (int x = 0; x < Board.Width - Position.x; x++)
        {
            Position dir = new Position(Position.x + x, Position.y);

            if (Board.Pieces[dir] != null)
                break;

            validMoves.Add(dir);
        }

        // check left of rook
        for (int x = 0; x < Position.x; x++)
        {
            Position dir = new Position(Position.x - x, Position.y);

            if (Board.Pieces[dir] != null)
                break;

            validMoves.Add(dir);
        }

        // check right of rook
        for (int x = 0; x < Board.Width - Position.x; x++)
        {
            Position dir = new Position(Position.x + x, Position.y);

            if (Board.Pieces[dir] != null)
                break;

            validMoves.Add(dir);
        }