c_random.hpp

#pragma once
#include <types.h>
 
/// @brief Random number generation helper class.
/// @ingroup clib
/// @unofficial
class cM_rand_c {
public:
 
    /// @brief Initializes the class with the given seed.
    cM_rand_c(u32 seed) : mSeed(seed) {}
 
    u32 ranqd1(u32 max); ///< Generates an integer between 0 and the given max.
    float ranqd2(); ///< Generates a floating point number between 0 and 1.
    float ranqd3(); ///< Generates a floating point number between -0.5 and 0.5.
 
    u32 mSeed; ///< The current seed.
 
private:
    /// @brief Implementation of the @p ranqd1 algorithm.
    /// @bug The implementation is flawed.
    /// @xlink{https://roadrunnerwmc.github.io/blog/2020/05/08/nsmb-rng.html, This post explains why}.
    inline u32 ranqdStep();
 
    static u32 mConst1; ///< Constant @p a from the @p ranqd1 algorithm.
    static u32 mConst2; ///< Constant @p c from the @p ranqd1 algorithm.
};