code: public static <T> Generator<PVector4D<T>> createNormal()
    {
      return new PVector4DGenerator<>(PrimitiveGenerators.doubles(
        GeneratorConstants.BOUND_NORMAL_DOUBLE_LOWER,
        GeneratorConstants.BOUND_NORMAL_DOUBLE_UPPER
      ));
    }
docs: Create a generator initialized with a default component generator that
  produces values in the range {@code [-1.0, 1.0]}.
  
  @param <T> A phantom type parameter
  
  @return A generator