Arduino code for my Halloween mask. It controls some RGB LEDs and red diffused LEDs. A button is used to change the "modes" of the mask.

Halloween Mask improved

// Mood Lamp
 
float RGB1[3];
float RGB2[3];
float INC[3];
 
int red, green, blue;
 
const int redPin = 11;          //eyes red
const int greenPin = 10;        //eyes green
const int bluePin = 9;          //eyes blue
const int fader = 5;            //fin leds

const int button = 2;
int state = 0;

void setup(){
  randomSeed(analogRead(0));
  RGB1[0] = 0;
  RGB1[1] = 0;
  RGB1[2] = 0;
 
  RGB2[0] = random(256);
  RGB2[1] = random(256);
  RGB2[2] = random(256);
  
  pinMode(button, INPUT);
  pinMode(redPin, OUTPUT);
  pinMode(greenPin, OUTPUT);
  pinMode(bluePin, OUTPUT);
  pinMode(fader, OUTPUT);
}
 
void loop(){
  switch(state){
  //state machine
  case 0:
    //off state
    while(!digitalRead(button)){
      switch_off();
      state = 0;
    }
    delay(500);
    state = 1;
    break;
    
  case 1:
    while(!digitalRead(button)){
      yellow_eyes(250, 250, 210);
      fin_fader(30, 40);
      state = 1;
    }
    delay(500);
    state = 2;
    break;
    
  case 2:
    while(!digitalRead(button)){
      digitalWrite(fader, HIGH);
      mood_mode();
      state = 2;
    }
    delay(500);
    digitalWrite(fader, LOW);
    state = 0;
  }
}

//function used in the state machine
void switch_off(){
  digitalWrite(redPin, LOW);
  digitalWrite(greenPin, LOW);
  digitalWrite(bluePin, LOW);
  
}

void yellow_eyes(int R, int G, int B){
  analogWrite(redPin, R);
  analogWrite(greenPin, G);
  analogWrite(bluePin, B);
}

void fin_fader(int fade_in, int fade_out){
  int i = 0;
  while(i<255){
    analogWrite(fader, i);
    i = i+5;
    delay(fade_in);
    if(digitalRead(button))
      return;
  }
  i = 255;
  while(i>0){
    analogWrite(fader, i);
    i = i-5;
    delay(fade_out);
    if(digitalRead(button))
      return;
  }
  digitalWrite(fader, LOW);
  delay(500);
}

void mood_mode(){
  randomSeed(analogRead(0));
 
  for (int x=0; x<256; x++){
    INC[x] = (RGB1[x] - RGB2[x]) / 256;
    if(digitalRead(button))
      return;
  }
   
  for (int x=0; x<256; x++){
    red = int(RGB1[0]);
    green = int(RGB1[1]);  
    blue = int(RGB1[2]);
   
    analogWrite(redPin, red);
    analogWrite(greenPin, green);
    analogWrite(bluePin, blue);
    delay(10);
   
    RGB1[0] -= INC[0];
    RGB1[1] -= INC[1];
    RGB1[2] -= INC[2];
    
    if(digitalRead(button))
      return;
  }
 
  for (int x=0; x<3; x++){
    RGB2[x] = random(556)-300;
    RGB2[x] = constrain(RGB2[x], 0, 255);
    if(digitalRead(button))
      return;
    delay(200);
  }
}