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Update q_math.c Q_rsqrt 10x #6

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Update q_math.c Q_rsqrt 10x #6

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9 changes: 3 additions & 6 deletions code/game/q_math.c
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Original file line number Diff line number Diff line change
Expand Up @@ -553,14 +553,11 @@ float Q_rsqrt( float number )
{
long i;
float x2, y;
const float threehalfs = 1.5F;

x2 = number * 0.5F;
y = number;
i = * ( long * ) &y; // evil floating point bit level hacking
i = 0x5f3759df - ( i >> 1 ); // what the fuck?
x2 = number * 0.5F;
i = 0x5f3759df - ( * ( long * ) &number >> 1 ); // evil floating point bit level hacking // what the fuck? 10x
y = * ( float * ) &i;
y = y * ( threehalfs - ( x2 * y * y ) ); // 1st iteration
y = y * ( 1.5F - ( x2 * y * y ) ); // 1st iteration
// y = y * ( threehalfs - ( x2 * y * y ) ); // 2nd iteration, this can be removed

#ifndef Q3_VM
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