what makes is fast is the use of requestAnimationFrame [1] (rather than setTimeout or setInterval) that exists in all modern browsers and simply applying css, letting the browser handle and GPU-accelerate as it sees fit. the only thing the js does is compute the matrices for each step/frame in fixed-length typed arrays.

[1] https://github.com/daniel-lundin/snabbt.js/blob/master/src/m...