I did not expect such a detailed code review (the fact that you wrote it on mobile impresses me even more), but I strongly agree with everything you mentioned. I think I was so caught up learning GLSL and its quirks, then playing and experimenting with the simulation, that I “forgot” my coding standards. Anyway, I’ll make sure to take some time to update both the code and the article following your recommandations.
Hey ! I (superficially) looked up the Belousov-Zhabotinsky reaction and can confirm it is related to the Gray-Scott model.
The Belousov-Zhabotinsky reaction involves an autocatalytic reaction and chemical species diffusing at different rates, just like in the Gray-Scott model. The main differences are related to constraints of doing actual chemistry instead of simulating it :