createCanvas(400, 400);

}

​

function draw() {

  background(50,0,100,50);

  stroke(255);

  strokeWeight(4);

  noFill();

  var nTurns = 100;

  var nPoints = 60*nTurns;

  var cx = width/2 ;

  var cy = height/2;

  var radius = 2;

  beginShape();

  for (var i=0; i<nPoints; i++){

    var t = map(i,0,(nPoints)-1,0,TWO_PI*nTurns);

    var px = cx + radius * cos(t);

    var py = cy + radius * sin(t);

    vertex(px, py);

    radius = radius *1.003;

  }

  endShape();

}