anchor.diff:  class MyScene extends Scene {
     MyScene(PerspectiveCamera camera): super(camera);
     Mesh mesh;
  +  bool rotateCamera = false;
   
     @override
     enter() {
  +
  +    var controllers = html.querySelector("#controllers");
       camera.position.setValues(0.0, 2.0, 4.0);
       camera.lookAt(new Vector3.zero());
       var url = "http://127.0.0.1:3030/orange/models/ogre/alric.orange";
  
positive.code:     loader.load(device.ctx, url).then((m) {
        m.position.setValues(0.0, -1.0, -1.0);
        m.animator.switchAnimation("Idle");
        var controllers = html.querySelector("#controllers");
        m.animator.animations.forEach((n, a) {
          var row = new html.DivElement();
          row.className = "row";
  
negative.code:       m.castShadows = true;
        mesh = m;
      });
  
      var row = new html.DivElement();
      row.className = "row";
      var radio = new html.CheckboxInputElement();
      radio.id = "rotate_camera";
      radio.name = "rotate_camera";
      radio.value = "rotate_camera";
      radio.onClick.listen((e) {
        rotateCamera = !rotateCamera;
      });
      var label = new html.LabelElement();
      label.htmlFor = radio.id;
      label.text = "Rotate Camera";
      row.children.add(radio);
      row.children.add(label);
      controllers.children.add(row);
  
      var plane = _createPlane(6.0);// new Plane(width: 10, height: 10);
      plane.rotation.rotateX(-PI / 2);
  