An Arduino powered Subnautica blood kelp

blood_kelp.ino

#define FADE 3

int max_brightness = 255 - FADE;
int min_brightness = FADE;


int brightness[4] = {240, 230, 225, 200}; 
int pins[4] = {5, 10, 6, 3};
int fade[4] = {FADE, FADE, FADE, FADE};

void setup() {
  for (int i = 0; i < 4; i++){
    pinMode(pins[i], OUTPUT);
  }
}

void loop() {
  for (int i = 0; i < 4; i++){
    breathe(i);
  }
  delay(40);
}

void breathe(int idx){
  brightness[idx] += fade[idx];
  if (brightness[idx] >= max_brightness || brightness[idx] <= min_brightness){
    fade[idx] = -fade[idx];
  }
  
  analogWrite(pins[idx], brightness[idx]);
}