Take 3 at getting a falling sand toy running. This one's the quick-and-dirty version, just using Javascript instead of mucking about with WASM - it turns out, in the details, WASM does not deal well with Shared Memory as of 2023-08-21.
To use the simulation, serve the files in www such that they are cross-origin isolated, say by running python3 example_sever.py. (Don't use the example server in production, it uses Python's example http.server which is not for that.)
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