arduino fastled radiate

#define NUM_LEDS = 150;
int HALF_POS = NUM_LEDS*0.5;

void radiate() {

    // this is for msgeq7 smoothing. every 10 milliseconds, data is read. not necessary.
    // but it smooths out the data a bit.
  //MILLISECONDS  = 10;
  //lowPass_audio = 0.17;
  //filter_min    = 150;
    // above is a low-pass data filter and data floor. I use these to smooth msgeq7 data in the following math located in my readAudio function:

      //prev_value  = left[band];
      //prev_value  -= (prev_value * EQ[band]);
      //left_value  = analogRead(AUDIO_LEFT_PIN);
      //left_value  = constrain(left_value, filter_min, filter_max);
      //left_value  = map(left_value, filter_min, filter_max, value_floor, filter_max );
      //left[band]  = prev_value + (left_value - prev_value) * lowPass_audio;


  // following code is not entirely necessary. just here to further filter the audio data
  zero  = mono[0] * 0.25;
//  if (zero < 40) {
//    zero -= (zero * 0.10);
//  }
  three = mono[3] * 0.23;
  if (three < 80) {
    three -= (three * 0.25);
  }
  six   = mono[6] * 0.25;
  if (six < 40) {
    six -= (six * 0.10);
  }

  leds[HALF_POS] = CRGB(zero, three, six);

  EVERY_N_MILLISECONDS(10) {
    for (int i = NUM_LEDS; i > HALF_POS; i--) {
      leds[i].blue = leds[i - 1].blue;
    }
  }
  EVERY_N_MILLISECONDS(20) {
    for (int i = NUM_LEDS; i > HALF_POS; i--) {
      leds[i].green = leds[i - 1].green;
    }
  }
  EVERY_N_MILLISECONDS(50) {
    for (int i = NUM_LEDS; i > HALF_POS; i--) {
      leds[i].red = leds[i - 1].red;
    }
  }
  for (int i = NUM_LEDS; i > HALF_POS; i--) {
    leds[HALF_POS - (i - HALF_POS)] = leds[i - 1];
  }

  //blur1d(leds, NUM_LEDS, 5); //blurring the led array a small amount makes for a pretty interesting effect
  FastLED.show();
}