Fast InvSqrt in Max

BlitzMax Forums/BlitzMax Programming/Fast InvSqrt in Max

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Azathoth
 #1
Heres one I made that alters the contents of the pointer directly so theres no need for 'ox' and replaces 'i'.
It was the fastest on my computer just barely though.
Function InvSqrtAza:Float(x:Float)

	Local xhalf:Float = 0.5*x
	Local ip:Int Ptr=Int Ptr(Varptr(x))
	ip[0]=$5f3759df-(ip[0] Shr 1)
	Return x *(1.5 - (xhalf*x*x))

End Function