title: Draw a basic triangle with Three.js
body: <p>I am triyng to learn three.js I want to dra a basic triangle however my codes do not work. </p>
  
  <pre><code>var scene = new THREE.Scene();
  var camera = new THREE.PerspectiveCamera( 70, window.innerWidth/window.innerHeight, 0.1, 1000 );
  camera.position.z = 10;
  
  
  var renderer = new THREE.WebGLRenderer();
  renderer.setSize( window.innerWidth, window.innerHeight );
  document.body.appendChild( renderer.domElement );
  
  var geometry = new THREE.Geometry();
  geometry.vertices= [new THREE.Vector3(2,1,0), new THREE.Vector3(1,3,0), new THREE.Vector3(3,4,0)]; 
  geometry.faces = [new THREE.Face3(0,1,2)];
  var mesh= new THREE.Mesh( geometry, new THREE.MeshBasicMaterial({ color: 0xffff00 }) );
  scene.add(mesh);
  
  
  renderer.render(scene, camera);
  </code></pre>
  
  <p>Where i am doing it wrong?</p>