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I'm getting a really nice smooth experience on my Intel HD Graphics 620 (7th gen intel integrated graphics, old and slow). Also just looking at the default ball scene, and I was really impressed how smooth it was on my system. I'm using chrome.

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I suspect this is possibly down to the use of readPixels and how slow that is on various devices. The engine seems to run in a worker and render to an offscreen canvas then transfer the image data in JS to the main thread before drawing it to a canvas there.

The transfer of image data only happens when we yield inside the engine which only occurs when you hit a breakpoint in script. Otherwise we're just rendering to the OffscreenCanvas and letting the normal flow blit it to the screen (not doing any copying).

I just did some profiling on Firefox and I feel like the profiling result doesn't quite make sense but it's saying that the majority of time is spent calling Performance.now() from the clock calls in C++. I'm wondering if that's because we're calling it too many times and maybe we should just call it once per frame.

FWIW my poor performance is in Chrome on Apple Silicon not Firefox.

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