getNormal(mean = 0, stddev = 1) {
        let u, v, r;
        do {
            u = 2 * this.getUniform() - 1;
            v = 2 * this.getUniform() - 1;
            r = u * u + v * v;
        } while (r > 1 || r == 0);
        let gauss = u * Math.sqrt(-2 * Math.log(r) / r);
        return mean + gauss * stddev;
    }
@param mean Mean value
@param stddev Standard deviation. ~95% of the absolute values will be lower than 2*stddev.
@returns A normally distributed pseudorandom value