split split mix sixty four

Sources/Voxelotl/Random/SplitMix64.swift

@@ -0,0 +1,25 @@
+public struct SplitMix64: RandomProvider, RandomSeedable {
+  public typealias Output = UInt64
+  public typealias SeedType = UInt64
+
+  public static var min: UInt64 { .max }
+  public static var max: UInt64 { .min }
+
+  private var _state: UInt64
+
+  public init(seed: UInt64) {
+    self._state = seed
+  }
+
+  public mutating func seed(_ value: UInt64) {
+    self._state = value
+  }
+
+  public mutating func next() -> UInt64 {
+    var x = self._state &+ 0x9E3779B97F4A7C15
+    x = (x ^ x &>> 30) &* 0xBF58476D1CE4E5B9
+    x = (x ^ x &>> 27) &* 0x94D049BB133111EB
+    self._state = x ^ x &>> 31
+    return self._state
+  }
+}