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@Tab3r
Created October 28, 2014 08:47
Fast Inverse Square Calculation
float FastInvSqrt(float x) {
float xhalf = 0.5f * x;
int i = *(int*)&x; // evil floating point bit level hacking
i = 0x5f3759df - (i >> 1); // what the fuck?
x = *(float*)&i;
x = x*(1.5f-(xhalf*x*x));
return x;
}
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