Vector4.random constructor

Vector4.random([Random rng ])

Generate random vector in the range (0, 0, 0, 0) to (1, 1, 1, 1). You can optionally pass your own random number generator.

Implementation 

factory Vector4.random([math.Random rng]) {
  rng ??= new math.Random();
  return new Vector4(
      rng.nextDouble(), rng.nextDouble(), rng.nextDouble(), rng.nextDouble());
}