| /// XorShiftRng |
| pub struct DeterministicRng { |
| count: usize, |
| x: u32, |
| y: u32, |
| z: u32, |
| w: u32, |
| } |
| |
| impl DeterministicRng { |
| pub fn new() -> Self { |
| DeterministicRng { count: 0, x: 0x193a6754, y: 0xa8a7d469, z: 0x97830e05, w: 0x113ba7bb } |
| } |
| |
| /// Guarantees that each returned number is unique. |
| pub fn next(&mut self) -> u32 { |
| self.count += 1; |
| assert!(self.count <= 70029); |
| let x = self.x; |
| let t = x ^ (x << 11); |
| self.x = self.y; |
| self.y = self.z; |
| self.z = self.w; |
| let w_ = self.w; |
| self.w = w_ ^ (w_ >> 19) ^ (t ^ (t >> 8)); |
| self.w |
| } |
| } |
