isleward/src/server/misc/random.js

let Random = function (a) {
	a = a === void 0 ? (new Date()).getTime() : a; this.N = 624; this.M = 397; this.MATRIX_A = 2567483615; this.UPPER_MASK = 2147483648; this.LOWER_MASK = 2147483647; this.mt = Array(this.N); this.mti = this.N + 1; this.init_by_array([a], 1);
}; Random.prototype.init_genrand = function (a) {
	this.mt[0] = a >>> 0; for (this.mti = 1; this.mti < this.N; this.mti++)a = this.mt[this.mti - 1] ^ this.mt[this.mti - 1] >>> 30, this.mt[this.mti] = (((a & 4294901760) >>> 16) * 1812433253 << 16) + (a & 65535) * 1812433253 + this.mti, this.mt[this.mti] >>>= 0;
};
Random.prototype.init_by_array = function (a, c) {
	let b, f, e; this.init_genrand(19650218); b = 1; f = 0; for (e = this.N > c ? this.N : c; e; e--) {
		let d = this.mt[b - 1] ^ this.mt[b - 1] >>> 30; this.mt[b] = (this.mt[b] ^ (((d & 4294901760) >>> 16) * 1664525 << 16) + (d & 65535) * 1664525) + a[f] + f; this.mt[b] >>>= 0; b++; f++; b >= this.N && (this.mt[0] = this.mt[this.N - 1], b = 1); f >= c && (f = 0);
	} for (e = this.N - 1; e; e--) {
		d = this.mt[b - 1] ^ this.mt[b - 1] >>> 30, this.mt[b] = (this.mt[b] ^ (((d & 4294901760) >>> 16) * 1566083941 << 16) + (d & 65535) * 1566083941) - b, this.mt[b] >>>= 0, b++, b >= this.N && (this.mt[0] =
this.mt[this.N - 1], b = 1);
	} this.mt[0] = 2147483648;
};
Random.prototype.genrand_int32 = function () {
	let a, c = [0, this.MATRIX_A]; if (this.mti >= this.N) {
		let b; this.mti === this.N + 1 && this.init_genrand(5489); for (b = 0; b < this.N - this.M; b++)a = this.mt[b] & this.UPPER_MASK | this.mt[b + 1] & this.LOWER_MASK, this.mt[b] = this.mt[b + this.M] ^ a >>> 1 ^ c[a & 1]; for (;b < this.N - 1; b++)a = this.mt[b] & this.UPPER_MASK | this.mt[b + 1] & this.LOWER_MASK, this.mt[b] = this.mt[b + (this.M - this.N)] ^ a >>> 1 ^ c[a & 1]; a = this.mt[this.N - 1] & this.UPPER_MASK | this.mt[0] & this.LOWER_MASK; this.mt[this.N - 1] = this.mt[this.M - 1] ^ a >>> 1 ^
c[a & 1]; this.mti = 0;
	}a = this.mt[this.mti++]; a ^= a >>> 11; a ^= a << 7 & 2636928640; a ^= a << 15 & 4022730752; a ^= a >>> 18; return a >>> 0;
}; Random.prototype.genrand_int31 = function () {
	return this.genrand_int32() >>> 1;
}; Random.prototype.genrand_real1 = function () {
	return this.genrand_int32() * (1 / 4294967295);
}; Random.prototype.random = function () {
	if (this.pythonCompatibility) this.skip && this.genrand_int32(), this.skip = !0; return this.genrand_int32() * (1 / 4294967296);
};
Random.prototype.genrand_real3 = function () {
	return (this.genrand_int32() + 0.5) * (1 / 4294967296);
}; Random.prototype.genrand_res53 = function () {
	let a = this.genrand_int32() >>> 5, c = this.genrand_int32() >>> 6; return (a * 67108864 + c) * 1.1102230246251565E-16;
}; Random.prototype.LOG4 = Math.log(4); Random.prototype.SG_MAGICCONST = 1 + Math.log(4.5); Random.prototype.exponential = function (a) {
	let c = this.random(); return -Math.log(c) / a;
};
Random.prototype.gamma = function (a, c) {
	if (a > 1) {
		for (let b = Math.sqrt(2 * a - 1), f = a - this.LOG4, e = a + b; ;) {
			let d = this.random(); if (!(d < 1.0E-7 || g > 0.9999999)) {
				let j = 1 - this.random(), i = Math.log(d / (1 - d)) / b, h = a * Math.exp(i), d = d * d * j, i = f + e * i - h; if (i + this.SG_MAGICCONST - 4.5 * d >= 0 || i >= Math.log(d)) return h * c;
			}
		}
	} else if (a === 1) {
		for (let g = this.random(); g <= 1.0E-7;)g = this.random(); return -Math.log(g) * c;
	} else {
		for (;;) {
			if (g = this.random(), h = (Math.E + a) / Math.E, g *= h, h = g <= 1 ? Math.pow(g, 1 / a) : -Math.log((h - g) / a), d = this.random(), g > 1) {
				if (d <= Math.pow(h,
					a - 1)) break;
			} else if (d <= Math.exp(-h)) break;
		} return h * c;
	}
}; Random.prototype.normal = function (a, c) {
	let b = this.lastNormal; this.lastNormal = NaN; if (!b) {
		let f = this.random() * 2 * Math.PI, e = Math.sqrt(-2 * Math.log(1 - this.random())), b = Math.cos(f) * e; this.lastNormal = Math.sin(f) * e;
	} return a + b * c;
}; Random.prototype.pareto = function (a) {
	let c = this.random(); return 1 / Math.pow(1 - c, 1 / a);
};
Random.prototype.triangular = function (a, c, b) {
	let f = (b - a) / (c - a), e = this.random(); return e <= f ? a + Math.sqrt(e * (c - a) * (b - a)) : c - Math.sqrt((1 - e) * (c - a) * (c - b));
}; Random.prototype.uniform = function (a, c) {
	return a + this.random() * (c - a);
}; Random.prototype.weibull = function (a, c) {
	let b = 1 - this.random(); return a * Math.pow(-Math.log(b), 1 / c);
};

global.random = new Random();
extend(true, random, {
	norm: function (low, high) {
		let mid = low + ((high - low) / 2);
		let range = mid - low;

		let roll = this.normal(0, 0.35);
		if (roll < -1)
			roll = -1;
		else if (roll > 1)
			roll = 1;

		let result = (mid + (roll * range));
		return result;
	},

	expNorm: function (low, high) {
		let roll = random.norm(0, 100);
		if (roll > 50)
			roll = 100 - roll;
		
		roll = (50 - roll) / 50;
		
		roll = low + ((high - low) * roll);

		return roll;
	}
});