interface RenderFrequencySample {
  public double get(Complex c, double frac);
  void subtractPeriodFrom(IAddPlateau audio, DoubleRange period, Complex intensity);
  
  public default void addPeriodTo(double[] samples, DoubleRange period, Complex intensity) {
    if (samples == null) ret;
    subtractPeriodFrom(new IAddPlateau {
      public void addPlateau(double start, double end, double intensity) {
        int i1 = ifloor(start), i2 = ifloor(end);
        for (int i = i1; i < i2; i++)
          samples[i] += intensity;
      }
    }, period, -intensity);
  }
}