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Highest priority:

• Clean up ramhorn_branch because it's fugly.
• See automata_scratch/examples.py and implement some of the tougher examples.
  • spiral_nested_2 & spiral_nested_3 (how to compose efficiently?)
  • twisty_torus

Important but less critical:

• Elegance & succinctness (my recent closure work may help with this):
  • Why must I repeat myself so much in these definitions?
  • What patterns can I factor out? I do some things regularly, like: the clockwise boundaries, the zigzag connections
  • Procedural macro to shorten this Tag::Parent, Tag::Body nonsense - and perhaps force to groups of 3?
• Docs on modules
• Grep for all TODOs in code, really.
• Look at performance. Can I save on copies of geometry by using Rc<OpenMesh> or the like? In many cases I have nothing but copied geometry. Can I pre-allocate vectors instead of extending/appending?
  • connect() is a big performance hot-spot: 85% of total time in one test, around 51% in extend(), 33% in clone(). It seems like I should be able to share geometry with the Rc (like noted above), defer copying until actually needed, and pre-allocate the vector to its size (which should be easy to compute).
• Look at everything in README.md in automata_scratch.
• I can't really do mutual recursion with the closure method, can I? I'd need actual functions for that.
• N.B. "Constants" outside the closure only work the way I think they should work if:
  • they're actually static
  • they implement Copy
  • the closure can move them
• Use an actual logging framework.
• Migrate tests to... well... actual tests.
• I am starting to see a pattern emerge in how I have to modularize things around closures. What can a macro do for me here?
• swept-isocontour stuff from /mnt/dev/graphics_misc/isosurfaces_2018_2019/spiral*.py

If I'm bored:

• Fix links in tri_mesh docs that use relative paths & do a PR?
• Look in https://www.nalgebra.org/quick_reference/# for "pour obtain". Can I fix this somehow? Looks like a French-ism that made its way in.
• Multithread! This looks very task-parallel anywhere that I branch.
• Would being able to name a rule node (perhaps conditionally under some compile-time flag) help for debugging?