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Doom Inverse Square Root Function Atom Feed

Updated over 2 years ago (06 Dec 2007 at 12:31 AM) history recent activity
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In Brief Doom's semi famous inverse square root function, more info about it at: http://www.beyond3d.com/content/articles/8/
Language C
# 's 
1float InvSqrt (float x){
2	float xhalf = 0.5f*x;
3	int i = *(int*)&x;
4	i = 0x5f3759df - (i>>1);
5	x = *(float*)&i;
6	x = x*(1.5f - xhalf*x*x);
7	return x;
8}

Doom's semi famous inverse square root function, more info about it at: http://www.beyond3d.com/content/articles/8/