class Particle extends VerletParticle2D{
  
  int radius;
  int age;
  int lifespan;
  boolean isDead;
  float decay;
  Vec2D vel;
  Vec2D acceleration;
  float mass;

  Particle(int x, int y){
   this(x,y, randomVector().normalize()); 
  }

  Particle(int x, int y, Vec2D v){
    super(x,y); 
    //this.radius = int(random(1,5));
    //this.radius = int(cos(y*.01) + sin( x * .01) + 2);
    this.radius = int((sin(x+y) + MAXRADIUS)* 2);
    this.age = 0;
    this.lifespan = int(random(200,2000));
    Vec2D offSet = randomVector().scale(random(1.0,3.0));
    this.vel = new Vec2D(v).scale(.25).add(offSet); 
    //this.vel = randomVector().normalize();
    this.decay = random(.95,.99);  
    acceleration = new Vec2D();
    
  }
  
  
  void update(){
    age++;
    if (age > lifespan){
      isDead = true;
      return;
    }
    this.vel.addSelf(acceleration);
    
    this.vel = vel.scale(decay);
    float angle = noise(x*.005, y*.005,age * .1) * 15.0;
    Vec2D noiseVec = new Vec2D(cos(angle),sin(angle));
    this.vel = vel.add(noiseVec.scale(.02 *(1.0 - age/lifespan)));
    this.x += vel.x;
    this.y += vel.y;
    acceleration.clear();
    //interpolateTo(getVelocity());
    float b = brightness(img.get(int(x/picScale),int(y/picScale)))/255.0;
    this.radius = int(MAXRADIUS * b);
    this.mass = radius * radius * .005;
    
  }

  void draw(){
   //pushStyle();
    //fill( brightness(img.get(int(x),int(y))));
    //noStroke();
    //fill(c);
    ellipse(x,y,radius, radius);
    //popStyle();
 } 
  
}