text: // Released under MIT License
  
  // Copyright (c) 2018 Jonathan Dent.
  
  // Permission is hereby granted, free of charge, to any person obtaining a copy
  // of this software and associated documentation files (the "Software"), to deal
  // in the Software without restriction, including without limitation the rights
  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  // copies of the Software, and to permit persons to whom the Software is
  // furnished to do so, subject to the following conditions:
  
  // The above copyright notice and this permission notice shall be included in
  // all copies or substantial portions of the Software.
  
  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  // SOFTWARE.
  
  #pragma once
  
  // Local libraries
  #include "utility/rng/i_rand_generator.h"
  
  // Standard libraries
  #include <cstdint>
  
  constexpr float inv_uint64 = 1.f / UINT64_MAX;
  
  // Taken from Xoroshiro128
  // Written in 2018 by David Blackman and Sebastiano Vigna (vigna@acm.org)
  
  static uint64_t rotl(const uint64_t x, int k)
  {
      return (x << k) | (x >> (64 - k));
  }
  
  class Xoro128 : public IRandGenerator
  {
    public:
      // Constructors
      Xoro128() = default;
  
      // Destructor
      ~Xoro128() override = default;
  
      float get_1_d() override;
  
      void seed_gen(uint64_t seed) override;
  
      float get_2d() override { return 0.f; }
  
    private:
      uint64_t s[2]{0x46961B5E381BCE6EULL, 0x55897310023CAE21ULL};
  };
  