//A physics circle
public class Ball{
  
  public Vector2D Pos;
  public Vector2D Vel;
  public Vector2D Force;  //primarily a buffer for force being applied this frame
  
  public float max_vel;
  public float min_vel;
  public float r;
  public float Mass;
  public float Elasticity;
  public boolean killMe;
  public boolean launched;
  public int liftOff;
  
  Ball()
  {
    Pos = new Vector2D();
    Vel = new Vector2D();
    Force = new Vector2D();
    
    max_vel = 150.0f;
    min_vel = 50.0f;
    r = .5f;
    Mass = 1.0f;
    Elasticity = 1.0f;
    killMe = false;  
    launched = false;
    liftOff = 0;
  }
  
  public void AddForce(Vector2D force)
  {
    Vel.limitMax(max_vel);
    Force.PlusEquals(force);
  }
 
  public void SubForce(Vector2D force)
  {
    Force.MinusEquals(force);
  }
 
 public void LimitMaxVel()
 {
   float maxVel = max_vel;
   Vel.limitMax(maxVel);
 }
 
  public void LimitMinVel()
 {
   float minVel = min_vel;
   Vel.limitMin(minVel);
 }
 
  public void CollideWithLineSeg(LineSeg2D ls)
  {
    //Insert a collision response function here
//    System.out.println("BOING!\n");
    Vel.Set((Vector2D.Reflect(Vel.Negative(),ls.UnitNorm())).Times(Elasticity));
  } 
  
  public void CollideWithPaddle(Paddle p)
  {
    
  }
  
}