3d Voronoi Tessellation

I had an idea for a project to create a rough simulation of mushroom growth using a graph based cellular automata. I needed a way to easily decide which cells should be neighbors and a way to transform the cells into a 3d triangle mesh to render. The Delaunay triangulation of the cells would work for discovering neighbors and taking its dual to get the Voronoi tessellation would work fine for rendering. I implemented the Bowyer-Watson algorithm in 3d in Javascript here, but even after adding some heuristics and more appropriate data structures it didn’t run fast enough for what I wanted it to do, so I left it at that.