PHPWarrior\Position::relative_direction PHP Method

    public function relative_direction($direction)
    {
        $direction = self::normalize_direction($direction);
        $offset = array_search($direction, self::$DIRECTIONS) - $this->direction_index;
        while ($offset > 3) {
            $offset -= 4;
        }
        while ($offset < 0) {
            $offset += 4;
        }
        return self::$RELATIVE_DIRECTIONS[$offset];
    }