odin-js-fundamentals-part-4/node_modules/pure-rand/lib/generator/XorShift.js

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2024-01-05 19:30:21 +00:00
"use strict";
exports.__esModule = true;
exports.xorshift128plus = void 0;
var XorShift128Plus = (function () {
function XorShift128Plus(s01, s00, s11, s10) {
this.s01 = s01;
this.s00 = s00;
this.s11 = s11;
this.s10 = s10;
}
XorShift128Plus.prototype.clone = function () {
return new XorShift128Plus(this.s01, this.s00, this.s11, this.s10);
};
XorShift128Plus.prototype.next = function () {
var nextRng = new XorShift128Plus(this.s01, this.s00, this.s11, this.s10);
var out = nextRng.unsafeNext();
return [out, nextRng];
};
XorShift128Plus.prototype.unsafeNext = function () {
var a0 = this.s00 ^ (this.s00 << 23);
var a1 = this.s01 ^ ((this.s01 << 23) | (this.s00 >>> 9));
var b0 = a0 ^ this.s10 ^ ((a0 >>> 18) | (a1 << 14)) ^ ((this.s10 >>> 5) | (this.s11 << 27));
var b1 = a1 ^ this.s11 ^ (a1 >>> 18) ^ (this.s11 >>> 5);
var out = (this.s00 + this.s10) | 0;
this.s01 = this.s11;
this.s00 = this.s10;
this.s11 = b1;
this.s10 = b0;
return out;
};
XorShift128Plus.prototype.jump = function () {
var nextRng = new XorShift128Plus(this.s01, this.s00, this.s11, this.s10);
nextRng.unsafeJump();
return nextRng;
};
XorShift128Plus.prototype.unsafeJump = function () {
var ns01 = 0;
var ns00 = 0;
var ns11 = 0;
var ns10 = 0;
var jump = [0x635d2dff, 0x8a5cd789, 0x5c472f96, 0x121fd215];
for (var i = 0; i !== 4; ++i) {
for (var mask = 1; mask; mask <<= 1) {
if (jump[i] & mask) {
ns01 ^= this.s01;
ns00 ^= this.s00;
ns11 ^= this.s11;
ns10 ^= this.s10;
}
this.unsafeNext();
}
}
this.s01 = ns01;
this.s00 = ns00;
this.s11 = ns11;
this.s10 = ns10;
};
return XorShift128Plus;
}());
var xorshift128plus = function (seed) {
return new XorShift128Plus(-1, ~seed, seed | 0, 0);
};
exports.xorshift128plus = xorshift128plus;