* with the given y-coordinate.
     */
    private int getLeftColumns(int y) {
        int leftColumns = leftSpace / tileWidth + 1;

        if ((y % 2) == 0) {
            if ((leftSpace % tileWidth) > 32) {
                leftColumns++;
            }
        } else {
            if ((leftSpace % tileWidth) == 0) {
                leftColumns--;
            }
        }

        return leftColumns;
    }