22 lines
530 B
Zig
22 lines
530 B
Zig
//! Generator to extend 64-bit seed values into longer sequences.
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//!
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//! The number of cycles is thus limited to 64-bits regardless of the engine, but this
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//! is still plenty for practical purposes.
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const SplitMix64 = @This();
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s: u64,
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pub fn init(seed: u64) SplitMix64 {
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return SplitMix64{ .s = seed };
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}
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pub fn next(self: *SplitMix64) u64 {
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self.s +%= 0x9e3779b97f4a7c15;
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var z = self.s;
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z = (z ^ (z >> 30)) *% 0xbf58476d1ce4e5b9;
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z = (z ^ (z >> 27)) *% 0x94d049bb133111eb;
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return z ^ (z >> 31);
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}
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