Hardware AJAX Loader using an Attiny85, 3 potentiometers and a 24 RGB LED ring

AjaxLoader.ino

#include <FastLED.h>

#define NUM_LEDS 24
#define NUM_DOTS 3
#define DATA_PIN 0
#define MAX_SPEED 60

using namespace std;

CRGB leds[NUM_LEDS];

class Dot {
    int resolution = 2048;
    int color;
    byte maxbrightness = 50;
    int current_speed = 0;
    float mean;
    float sigma;
    int currentposition = 0;
    int stepwidth;
  public:
    void setColor(byte);
    void setCurrentSpeed(int);
    void next();
    byte getBrightness(byte);
    CHSV getColor(byte);
};

void Dot::setColor (byte _color) { 
  color = _color; 
  stepwidth = resolution / NUM_LEDS;
  mean = resolution / 2;
  sigma = resolution / 18;
}
void Dot::setCurrentSpeed (int _speed) { 
  current_speed = _speed; 
}
void Dot::next () { 
  currentposition = (currentposition + current_speed) % resolution; 
}
byte Dot::getBrightness (byte led) { 
  int x = (currentposition + led * stepwidth);
  if (x < 0) { x+=resolution; }
  x %= resolution;
  return maxbrightness * exp(-0.5 * pow((x - mean) / sigma, 2.));
}
CHSV Dot::getColor(byte led) {
  return CHSV(color, 255, getBrightness(led));
}

Dot dots[NUM_DOTS];

void setup() {

  dots[0].setColor(HUE_RED);
  dots[1].setColor(HUE_GREEN);
  dots[2].setColor(HUE_BLUE);

  dots[0].setCurrentSpeed(0);
  dots[1].setCurrentSpeed(-5);
  dots[2].setCurrentSpeed(5);
  
  FastLED.addLeds<WS2812B, DATA_PIN>(leds, NUM_LEDS);
}

void loop() {
  dots[0].setCurrentSpeed(map(analogRead(A1), 0, 1023, MAX_SPEED, -1 * MAX_SPEED));
  dots[1].setCurrentSpeed(map(analogRead(A2), 0, 1023, MAX_SPEED, -1 * MAX_SPEED));
  dots[2].setCurrentSpeed(map(analogRead(A3), 0, 1023, MAX_SPEED, -1 * MAX_SPEED));
  
  for (int i=0; i<NUM_DOTS; i++) {
    dots[i].next();
  }
  for (int led=0; led<NUM_LEDS; led++) {
    for (int i=0; i<NUM_DOTS; i++) {
      if (i==0) {
        leds[led] = dots[i].getColor(led);
      } else {
        leds[led] += dots[i].getColor(led);
      }
    }
  }
  FastLED.show();
  delay(1);
}