This reminds me of a paper[0] I co-wrote during a college internship that involved simulating the evolution of a Brownian system of particles with production and annihilation rules as the evolution of probability density distributions for each particle type within a partitioned cubic periodic box. Because we were interested in how these particles segregated spatially, visualization was a matter of finding the boundaries separating each domain of particles. I made some fun little videos of the evolution of the system over time (which tracks very conspicuously the entropy production, plotted in the paper), but unfortunately, they've since been taken down from the institute's website where they were hosted. (The paper does contain some snapshots that went into these visualizations, however.)

[0] https://pubs.aip.org/aip/jcp/article-abstract/122/17/174105/...