(function() {
  var N, angles, height, points, side, sum, svg, theta_prev, vis, width;

  svg = d3.select('svg');

  width = svg[0][0].getBoundingClientRect().width;

  height = svg[0][0].getBoundingClientRect().height;

  side = Math.min(width, height);

  vis = svg.append('g').attr({
    transform: "translate(" + (width / 2) + " " + (height / 2) + ")"
  });

  N = 20 + 20 * Math.round(Math.random());

  angles = d3.range(N).map(function(i) {
    return Math.random();
  });

  sum = d3.sum(angles);

  theta_prev = 0;

  points = angles.map(function(a) {
    var rho, theta;

    theta = theta_prev + a * 2 * Math.PI / sum;
    theta_prev = theta;
    rho = d3.random.normal(side / 3, side / 32)();
    return [rho * Math.cos(theta), rho * Math.sin(theta)];
  });

  vis.append('path').datum(points).attr({
    "class": 'polygon',
    d: function(points) {
      return "M" + (points.join('L')) + "Z";
    }
  });

  vis.selectAll('.dots').data(points).enter().append('circle').attr({
    "class": 'dot',
    cx: function(p) {
      return p[0];
    },
    cy: function(p) {
      return p[1];
    },
    r: 2.5
  });

}).call(this);