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/ Quake2_InvSqrt.h
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August 9, 2025 10:01
A simple implementation of the Quake 2 inverse square root algorithm.
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| #ifndef QUAKE2_INVSQRT_HPP | |
| #define QUAKE2_INVSQRT_HPP | |
| // Fast inverse square root algorithm | |
| // Credit: Quake III Arena | |
| // (Obsolete now due to native CPU support) | |
| float invsqrt (float num) { | |
| long i = *(long*) &y; // Read the bits of the float as an integer |