mgl_random_xorshift.h

[詳解]

// SPDX-License-Identifier: Zlib
/* ------------------------------------------------------------------------- */
/* ------------------------------------------------------------------------- */
 
#ifndef INCGUARD_MGL_RANDOM_H_1626922980
#define INCGUARD_MGL_RANDOM_H_1626922980
 
#include <cstdint>
 
namespace MGL::Random
{
class XorShift
{
public:
    /* ------------------------------------------------------------------------- */
    /* ------------------------------------------------------------------------- */
    explicit constexpr XorShift(uint32_t seed = 0) noexcept
        : _seed(seed)
    {}
 
    /* ------------------------------------------------------------------------- */
    /* ------------------------------------------------------------------------- */
    constexpr uint32_t Get() noexcept
    {
        _seed = _seed ^ (_seed << 13);
        _seed = _seed ^ (_seed >> 17);
        _seed = _seed ^ (_seed << 5);
 
        return _seed;
    }
 
    /* ------------------------------------------------------------------------- */
    /* ------------------------------------------------------------------------- */
    constexpr float GetFloat() noexcept
    {
        return static_cast<float>(static_cast<double>(Get()) / static_cast<double>(0xFFFFFFFF));
    }
 
    /* ------------------------------------------------------------------------- */
    /* ------------------------------------------------------------------------- */
    [[nodiscard]] constexpr uint32_t GetSeed() const noexcept
    {
        return _seed;
    }
 
    /* ------------------------------------------------------------------------- */
    /* ------------------------------------------------------------------------- */
    constexpr void SetSeed(uint32_t seed) noexcept
    {
        _seed = seed;
    }
 
private:
    uint32_t _seed;
};
}    // namespace MGL::Random
 
#endif    // INCGUARD_MGL_RANDOM_H_1626922980
 
// vim: et ts=4 sw=4 sts=4