Phyllotaxis pinwheel

inlet.js

// View live at http://enjalot.com/cypress/3114111
// Original at http://www.jasondavies.com/sunflower-phyllotaxis/

var w = tributary.sw,
    h = tributary.sh,
    p = 5,
    n = 760,
    k = 1/4000;
    scale = 10;

tributary.init = function(ctx) {
  d3.select('#display').style('background', '#111');
};
tributary.run = function(ctx,t) {
  tributary.clear(); //helper function to clear the canvas
  
  GOLDEN_ANGLE = Math.PI * (t/40000 + Math.sqrt(k*t));
  
  var points = d3.range(1, n).map(place);
  
  points.forEach(circle);
  
  function circle(p,i) {
    ctx.fillStyle = 'hsla(' + Math.round(310+50*i/n) + ',50%,60%,' + Math.sqrt((i/n)) + ')'
    ctx.beginPath();
    ctx.arc(p[0],p[1],4,0,2*Math.PI);
    ctx.fill();
  }
  
  function place(n) {
    var r = Math.sqrt(n),
        a = n * GOLDEN_ANGLE;
    return [scale * r * Math.cos(a)+w/2, scale * r * Math.sin(a)+h/2];
  }
};