public function getDistance($X1, $Y1, $X2, $Y2)
    {
        return sqrt(($X2 - $X1) * ($X2 - $X1) + ($Y2 - $Y1) * ($Y2 - $Y1));
    }
public function getDistance($X1, $Y1, $X2, $Y2)
    {
        return sqrt(($X2 - $X1) * ($X2 - $X1) + ($Y2 - $Y1) * ($Y2 - $Y1));
    }
public function getDistance ( $ X1 , $ Y1 , $ X2 , $ Y2 ) { return sqrt ( ( $ X2 - $ X1 ) * ( $ X2 - $ X1 ) + ( $ Y2 - $ Y1 ) * ( $ Y2 - $ Y1 ) ) ; }
Return the distance between two points
@param int $X1
@param int $Y1
@param int $X2
@param int $Y2
@return int|float
Return the distance between two points