Show HN: Full-screen 2D Cellular Automata

Nice, one file of vanilla JavaScript, an HTML file, and a Readme. I know that in some contexts there are advantages to having a bunch of separate JavaScript modules each in its own file, tests, build steps, frameworks, etc. but I like how this project does not add any of that sort of complexity given that it is not needed.

Just a note: when you are copying one canvas' data to another's, I think you can use a TypedArray method like "set" to do the whole thing in one go. Not sure if the performance would be better, but it might be worth trying. In any case, there is no need to do a nested iteration over the width and the height, you can just iterate over the entire data array in one go.