// Polar coordinates (r, theta) are converted to Cartesian (x,y) 
// for use in the ellipse() function.
float r = 0; 
float theta = 0;

float mySize=100;		//set the size of the ellipse

void setup() {
  size(500,500);
  background(50);
  smooth();
  frameRate(200); 
}

void draw() {
  
  //draw the ellipse
  stroke(255);strokeWeight(2);noFill();
  ellipse(width/2,height/2,2*mySize,2*mySize); 
  
  
  // Polar to Cartesian conversion
  float x = r * cos(theta);
  float y = r * sin(theta);
  
  // Draw an ellipse at x,y
  noStroke();
  fill(0);
  ellipse(x + width/2, y + height/2, 7, 7); // Adjust for center of window
  
  // Increment the angle
  theta += 0.11;
  r = r+.15;
  
  
  if(r > mySize)  //check if reached the ellipse
  {
   noLoop(); 
   println("yay");
  }
  
} 

float r = 0; 
float theta = 0;

// It's always a good idea to use meaningful variable names:
// Makes life a lot easier when you're working with a lot of code!
float radiusLimit =100;		

void setup() {
  size(500,500);
  background(50);
  smooth();
  // To make things move faster don't just increase the frameRate.
  // Beyond a certain point it's going to be limited by the CPU, 
  // so results will depend on the system the sketch is running 
  // on...
  frameRate(60); 
}

void draw() {
  // I'd avoid getting into the habit of using noLoop()
  // In this case it works perfectly well, but it means your draw 
  // loop quits altogether: not always what you want
  if (r < radiusLimit) {
      float x = r * cos(theta);
      float y = r * sin(theta);
      
      noStroke();
      fill(0);
      ellipse(x + width/2, y + height/2, 7, 7);
      
      theta += 0.11;
      r = r+.15;
      
      // By drawing the ellipse at the end it is always the last 
      // thing to be drawn and is therefore always on top of 
      // the black ellipses.
      stroke(255);strokeWeight(2);noFill();
      ellipse(width/2,height/2,2*radiusLimit,2*radiusLimit); 
  }  

  
} 

Ball ball1;
Ball ball2;
Spiral spiral1;


void setup() {
  size(1100,800);
  smooth();

  ball1 = new Ball(55);
  ball2 = new Ball(175);
  spiral1 = new Spiral(ball1.x, ball1.y, ball1.r);
  spiral1.radiusLimit = ball1.r;
  
  
}

void draw() {
  background(50);

  ball1.move();
  ball2.move();
  if (ball1.intersect(ball2)) {
    ball1.highlight();
    ball2.highlight();
  }

  ball1.display();
  ball2.display();
  
  
spiral1.display();


}

class Ball {

  int redc = 0;
  
  float r;
  float x,y;
  float xspeed,yspeed;
  color c = color(200,200);

  Ball(float tempR) {
    r = tempR;
    x = random(width);
    y = random(height);
    xspeed = random(0,5);
    yspeed = random(0,5);
  }

  void move() {
    x += xspeed;
    y += yspeed;
    if (x > width || x < 0) {
	xspeed *= -1;
    }
    if (y > height || y < 0) {
	yspeed *= -1;
    }
  }

  
  void highlight() {

    
    c = color(redc,0,0,99);
    redc = redc+1;
    if (redc > 255) {
	redc = redc -1;
  }
  }

  void display() {
    stroke(0);
    strokeWeight(15);
    fill(c);
    ellipse(x,y,r*2,r*2);
    c = color(0,150,0);
  }

  
  boolean intersect(Ball other) {
    float distance = dist(x,y,other.x,other.y);
    if (distance < r + other.r) {
	return true;
    } else {
	return false;
    }
  }
}

class Spiral {

  float r = 0;
  float theta = 0;
  float radiusLimit = 0;
  float[] x= {0};
  float[] y= {0};     

  Spiral(float tempX,float tempY,float tempradiusLimit) {

    x[0] = tempX;
    y[0] = tempY;
    radiusLimit =tempradiusLimit;
  }


  void display() {

    if (r <= radiusLimit) 
     
	{
	float _x = r * cos(theta);
	float _y = r * sin(theta);

	x=append(x,_x);
	y=append(y,_y);

	noStroke();
	fill(0);
	
	for(int i=0;i<x.length;i++)  ellipse(x[i] + ball1.x, y[i] + ball1.y, 5, 5);
	   
	theta += 0.11;
	r = r+.15;

    }  
  
  } 
}