Calculate Pixel Distance

Func _CalculatePixelDistance($x1, $y1, $z1=0, $x2=0, $y2=0, $z2=0)
    Local $x, $y, $z, $d
    If ($x2 = $x1) And ($y2 = $y1) And ($z1 = $z2) Then
        Return 0
    Else
        $x = $x2 - $x1
        $y = $y2 - $y1
        $z = $z2 - $z1
        $d = Sqrt($x^2 + $y^2 + $z^2)
        Return $d
    EndIf
EndFunc