Impressive, but there is a noticeable lag after modifying the terrain or moving the camera. Is there a way to know if the browser is using the GPU or CPU for rendering, and is there are way to see the milliseconds per frame?

It looks like a layout/style/composition issue with the browser engine.

In Safari I'm seeing 91% CPU time on paint, 6% on layout, 2% on styles. It looks like it's taking somewhere between 100-200ms on my machine to chunk through a state change each time.

> Is there a way to know if the browser is using the GPU or CPU for rendering, and is there are way to see the milliseconds per frame?

For Safari, you would go to the Web Inspector and navigate to the Timelines tab. Chrome has a similar thing.