class firefly{

  float x,y;
  int line_length = 1;
  int level = 100;
  float i=0;
  float j=0;
  float angle = 0;
  float theta = 0.0;
  float rand_col;
  color blink = 255;
  boolean on = false;
  float dia = 5;

  // CONSTRUCTOR
  firefly(float xpos, float ypos) {
     x = xpos;
     y = ypos;
  }

  // main function to operate object
  void go() {
    stroke(255);
    angle = random(angle-.1*PI, angle+.1*PI);

    i = line_length*cos(angle);
    j = line_length*sin(angle);
    x += i;
    y += j;
    
    borders();

    rand_col = random(0,100);
    if(rand_col > 98 && !on){
      blink = 255;
      on = true;
    }
    fill(blink, blink, 0);
    noStroke();
    ellipse(x,y,dia,dia);

    theta += .01*PI;
    blink *= 0.8;
    dia -= 0.5;

    reset();

  }  
  
  void reset(){
    if(blink <= 0){
      blink = 0; 
      on = false;
      dia = 5;
    }
  }
  
  void borders(){
    if(x > width){ 
      x = 0; 
    }
    if(x < 0){ 
      x = width;
    }
    if(y > height){
      y = 0; 
    }
    if(y < 0){ 
      y = height;
    }
  }
}