73 lines
3.0 KiB
JavaScript
73 lines
3.0 KiB
JavaScript
|
"use strict";
|
||
|
|
exports.__esModule = true;
|
||
|
|
var MersenneTwister = (function () {
|
||
|
|
function MersenneTwister(states, index) {
|
||
|
|
this.states = states;
|
||
|
|
this.index = index;
|
||
|
|
}
|
||
|
|
MersenneTwister.twist = function (prev) {
|
||
|
|
var mt = prev.slice();
|
||
|
|
for (var idx = 0; idx !== MersenneTwister.N - MersenneTwister.M; ++idx) {
|
||
|
|
var y_1 = (mt[idx] & MersenneTwister.MASK_UPPER) + (mt[idx + 1] & MersenneTwister.MASK_LOWER);
|
||
|
|
mt[idx] = mt[idx + MersenneTwister.M] ^ (y_1 >>> 1) ^ (-(y_1 & 1) & MersenneTwister.A);
|
||
|
|
}
|
||
|
|
for (var idx = MersenneTwister.N - MersenneTwister.M; idx !== MersenneTwister.N - 1; ++idx) {
|
||
|
|
var y_2 = (mt[idx] & MersenneTwister.MASK_UPPER) + (mt[idx + 1] & MersenneTwister.MASK_LOWER);
|
||
|
|
mt[idx] = mt[idx + MersenneTwister.M - MersenneTwister.N] ^ (y_2 >>> 1) ^ (-(y_2 & 1) & MersenneTwister.A);
|
||
|
|
}
|
||
|
|
var y = (mt[MersenneTwister.N - 1] & MersenneTwister.MASK_UPPER) + (mt[0] & MersenneTwister.MASK_LOWER);
|
||
|
|
mt[MersenneTwister.N - 1] = mt[MersenneTwister.M - 1] ^ (y >>> 1) ^ (-(y & 1) & MersenneTwister.A);
|
||
|
|
return mt;
|
||
|
|
};
|
||
|
|
MersenneTwister.seeded = function (seed) {
|
||
|
|
var out = Array(MersenneTwister.N);
|
||
|
|
out[0] = seed;
|
||
|
|
for (var idx = 1; idx !== MersenneTwister.N; ++idx) {
|
||
|
|
var xored = out[idx - 1] ^ (out[idx - 1] >>> 30);
|
||
|
|
out[idx] = (Math.imul(MersenneTwister.F, xored) + idx) | 0;
|
||
|
|
}
|
||
|
|
return out;
|
||
|
|
};
|
||
|
|
MersenneTwister.from = function (seed) {
|
||
|
|
return new MersenneTwister(MersenneTwister.twist(MersenneTwister.seeded(seed)), 0);
|
||
|
|
};
|
||
|
|
MersenneTwister.prototype.clone = function () {
|
||
|
|
return new MersenneTwister(this.states, this.index);
|
||
|
|
};
|
||
|
|
MersenneTwister.prototype.next = function () {
|
||
|
|
var nextRng = new MersenneTwister(this.states, this.index);
|
||
|
|
var out = nextRng.unsafeNext();
|
||
|
|
return [out, nextRng];
|
||
|
|
};
|
||
|
|
MersenneTwister.prototype.unsafeNext = function () {
|
||
|
|
var y = this.states[this.index];
|
||
|
|
y ^= this.states[this.index] >>> MersenneTwister.U;
|
||
|
|
y ^= (y << MersenneTwister.S) & MersenneTwister.B;
|
||
|
|
y ^= (y << MersenneTwister.T) & MersenneTwister.C;
|
||
|
|
y ^= y >>> MersenneTwister.L;
|
||
|
|
if (++this.index >= MersenneTwister.N) {
|
||
|
|
this.states = MersenneTwister.twist(this.states);
|
||
|
|
this.index = 0;
|
||
|
|
}
|
||
|
|
return y;
|
||
|
|
};
|
||
|
|
MersenneTwister.N = 624;
|
||
|
|
MersenneTwister.M = 397;
|
||
|
|
MersenneTwister.R = 31;
|
||
|
|
MersenneTwister.A = 0x9908b0df;
|
||
|
|
MersenneTwister.F = 1812433253;
|
||
|
|
MersenneTwister.U = 11;
|
||
|
|
MersenneTwister.S = 7;
|
||
|
|
MersenneTwister.B = 0x9d2c5680;
|
||
|
|
MersenneTwister.T = 15;
|
||
|
|
MersenneTwister.C = 0xefc60000;
|
||
|
|
MersenneTwister.L = 18;
|
||
|
|
MersenneTwister.MASK_LOWER = Math.pow(2, MersenneTwister.R) - 1;
|
||
|
|
MersenneTwister.MASK_UPPER = Math.pow(2, MersenneTwister.R);
|
||
|
|
return MersenneTwister;
|
||
|
|
}());
|
||
|
|
function default_1(seed) {
|
||
|
|
return MersenneTwister.from(seed);
|
||
|
|
}
|
||
|
|
exports["default"] = default_1;
|