stellar

0 #ifndef STELLAR_RANDOM_H

1 #define STELLAR_RANDOM_H

2

3 #include "utils.hpp"

4

5 class Random {

6 public:

7 constexpr Random(void) = default;

8 constexpr Random(U64 seed) : state(seed) {}

9

10 constexpr U64 operator()(void) { return get_U64(); }

11

12 constexpr void reset(void) { state = seed; }

13

14 constexpr U32 get_U32(void) {

15 U32 number = state;

16

17 number ^= number << 13;

18 number ^= number >> 17;

19 number ^= number << 5;

20

21 return state = number;

22 }

23

24 constexpr U64 get_U64(void) {

25 U64 n1, n2, n3, n4;

26

27 n1 = (U64)(get_U32()) & C64(0xFFFF);

28 n2 = (U64)(get_U32()) & C64(0xFFFF);

29 n3 = (U64)(get_U32()) & C64(0xFFFF);

30 n4 = (U64)(get_U32()) & C64(0xFFFF);

31

32 return n1 | (n2 << 16) | (n3 << 32) | (n4 << 48);

33 }

34

35 private:

36 static inline constexpr const U32 seed = C32(1804289383);

37 U32 state = seed;

38 };

39

40 #endif