In this video we will take an in depth look at the fast inverse square root and see where the mysterious number 0x5f3759df comes from. This algorithm became famous after id Software open sourced the engine for Quake III. On the way we will also learn about floating point numbers and newton's method.
D. Ingalls, T. Kaehler, J. Maloney, S. Wallace, and A. Kay. OOPSLA '97: Proceedings of the 12th ACM SIGPLAN conference on Object-oriented programming, systems, languages, and applications, page 318-326. New York, NY, ACM Press, (1997)