text: // Daniel Shiffman
  // http://codingtra.in
  // http://patreon.com/codingtrain
  // Code for this video: https://youtu.be/Cl_Gjj80gPE
  
  var yoff = 0.0;
  
  function setup() {
    createCanvas(400, 400);
  }
  
  function draw() {
    background(0);
  
    translate(width / 2, height / 2);
  
    var radius = 150;
  
    beginShape();
    var xoff = 0;
    for (var a = 0; a < TWO_PI; a += 0.1) {
      var offset = map(octaveperlin(xoff, yoff), 0, 1, -25, 25);
      var r = radius + offset;
      var x = r * cos(a);
      var y = r * sin(a);
      vertex(x, y);
      xoff += 0.1;
      //ellipse(x, y, 4, 4);
    }
    endShape();
  
    yoff += 0.01;
  }
  
  