// Daniel Shiffman

// http://natureofcode.com

​

// Simple Recursion

​

function setup() {

  createCanvas(640,360);  

}

​

function draw() {

  background(51);

  drawCircle(width/2,height/2,width); 

  noLoop();

}

​

// Very simple function that draws one circle 

// and recursively calls itself

function drawCircle(x,y,r) {

  stroke(255);

  noFill();

  ellipse(x, y, r, r);

  // Exit condition, stop when radius is too small

  if(r > 2) {

    r *= 0.75;

    // Call the function inside the function! (recursion!)

    drawCircle(x, y, r);   

  }       

}