Multithreaded falling sand engine stress test and dirty area visualizations

In this video I stress test my (rather simple) multithreaded falling sand engine. The order in which chunks are updated is something I discovered independently when programming the light updates for my Minecraft clone. Later I watched the Noita dev talk and got inspired to apply it to a falling sand engine too. Basically I rediscovered the way Noita updates it's chunk in a different, but similar domain.
Also I implemented dirty rectangles, meaning chunks only update what needs to be updated. This also adds a cool effect of some particles that are on the ground already staying still instead of falling down further (you can see it in the video where the pyramids are not totally perfect but have some jagged lines). This is actually desirable in a game context, since it adds a bit of a natural feel to the sand.
I also did my very best to prevent visible chunk borders as much as possible, but due to the fundamental way chunks update, there is no 100% fix. Only tricks to make it less obvious.