I had the same thought. Already filed a bug on game_loop :)

On Saturday, March 23, 2013, Don wrote:

> In example/simple/skeletal_animation_cpu/sample.dart:
>
> >    _gameLoop.onResize = onResize;
> >    _gameLoop.onUpdate = onFrame;
> >    _gameLoop.onRender = onRender;
> > -  _gameLoop.onPointerLockChange = onPointerLockChange;
> > +  //_gameLoop.onPointerLockChange = onPointerLockChange;
> > +
> > +  canvas.onMouseWheel.listen((ev) {
>
> Ah yes. I didn't realize game_loop didn't have that. I'm fine with
> updating it once game_loop has this functionality.
>
> —
> Reply to this email directly or view it on GitHub<https://github.com/johnmccutchan/spectre/pull/69/files#r3502640>
> .
>