60 lines
2.0 KiB
JavaScript
60 lines
2.0 KiB
JavaScript
var XorShift128Plus = (function () {
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function XorShift128Plus(s01, s00, s11, s10) {
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this.s01 = s01;
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this.s00 = s00;
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this.s11 = s11;
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this.s10 = s10;
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}
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XorShift128Plus.prototype.clone = function () {
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return new XorShift128Plus(this.s01, this.s00, this.s11, this.s10);
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};
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XorShift128Plus.prototype.next = function () {
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var nextRng = new XorShift128Plus(this.s01, this.s00, this.s11, this.s10);
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var out = nextRng.unsafeNext();
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return [out, nextRng];
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};
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XorShift128Plus.prototype.unsafeNext = function () {
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var a0 = this.s00 ^ (this.s00 << 23);
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var a1 = this.s01 ^ ((this.s01 << 23) | (this.s00 >>> 9));
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var b0 = a0 ^ this.s10 ^ ((a0 >>> 18) | (a1 << 14)) ^ ((this.s10 >>> 5) | (this.s11 << 27));
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var b1 = a1 ^ this.s11 ^ (a1 >>> 18) ^ (this.s11 >>> 5);
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var out = (this.s00 + this.s10) | 0;
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this.s01 = this.s11;
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this.s00 = this.s10;
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this.s11 = b1;
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this.s10 = b0;
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return out;
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};
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XorShift128Plus.prototype.jump = function () {
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var nextRng = new XorShift128Plus(this.s01, this.s00, this.s11, this.s10);
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nextRng.unsafeJump();
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return nextRng;
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};
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XorShift128Plus.prototype.unsafeJump = function () {
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var ns01 = 0;
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var ns00 = 0;
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var ns11 = 0;
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var ns10 = 0;
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var jump = [0x635d2dff, 0x8a5cd789, 0x5c472f96, 0x121fd215];
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for (var i = 0; i !== 4; ++i) {
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for (var mask = 1; mask; mask <<= 1) {
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if (jump[i] & mask) {
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ns01 ^= this.s01;
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ns00 ^= this.s00;
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ns11 ^= this.s11;
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ns10 ^= this.s10;
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}
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this.unsafeNext();
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}
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}
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this.s01 = ns01;
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this.s00 = ns00;
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this.s11 = ns11;
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this.s10 = ns10;
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};
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return XorShift128Plus;
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}());
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export var xorshift128plus = function (seed) {
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return new XorShift128Plus(-1, ~seed, seed | 0, 0);
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};
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