Turtle drawing program with branches

turtle2.pde

class Point{
  float x,y;
  Point(float _x, float _y){
    x = _x;
    y = _y;
  }
};

class Turtle{
 Point p;
 float a; // angle
 float s; // speed
 
 float rv; // rotational velocity
 
 Turtle(Point _p){
   p = _p;
   a = random(TWO_PI);
   s = random(1.0);
   rv = random(1.0)-0.5;
 }
 Turtle(Point _p,float _a,float _s){
      p = _p;
   a = _a;
   s = _s;
   rv = random(1.0)-0.5;
 }
 
 
 void update(){
   rv = random(0.1)-0.05;
   a += rv;
   
   p.x += cos(a)*s;
   p.y += sin(a)*s;
 }
 void draw(){
  point(p.x,p.y); 
 }
}

Turtle t;



ArrayList<Turtle> turtles;

void setup(){
  stroke(255,255,255,64);
  turtles = new ArrayList<Turtle>();
  
 size(1920,1080);
 background(0);
 for(int i=0;i<1;i++){
   
 t = new Turtle(new Point(width/2,height/2));
 turtles.add(t);
 }
}
void draw(){
   for(int i=0;i<turtles.size();i++){
     t = turtles.get(i); 
     t.update();
   }
    for(int i=0;i<turtles.size();i++){
      t = turtles.get(i);
      t.draw();
    }
  
}
void mousePressed(){
  
  int numTurtles = turtles.size();
  
      for(int i=0;i<numTurtles;i++){
      t = turtles.get(i);
      Turtle t2 = new Turtle(new Point(t.p.x,t.p.y));
      turtles.add(t2);
    }
}