<!-- 

This code was mostly written by Mike Bostock, for one of his talks. 

I've borrowed it to give a talk about d3.js. 

-->
<!DOCTYPE html>
<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html;charset=utf-8"/>
    <title>RiftRay - Shadertoy for Oculus Rift</title>
    <script type="text/javascript" src="http://mbostock.github.com/d3/d3.js"></script>
    <style type="text/css">

body {
  background: #000;
  position: relative;
  width: 1024px;
  height: 768px;
  margin: auto;
  overflow