Polygon::getPerimeter PHP Method

    public function getPerimeter()
    {
        $return = null;
        if (count($this->points) >= 2) {
            $perimeterPoints = $this->points;
            $perimeterPoints[] = $perimeterPoints[0];
            $perimeter = 0;
            for ($i = 0; $i < count($this->points); $i++) {
                $perimeter += Point::distance($perimeterPoints[$i], $perimeterPoints[$i + 1]);
            }
            $return = $perimeter;
        }
        return $return;
    }