ah ha. I wondered about pickup sticks in May 2019 which fed into one of the questions (about foreground/background detection and how T shapes indicate to our brains that there is a 3rd dimension here) which led to discovering mathematical morphology, which led me into understanding posets (partial order sets).
Can maze hallway turns be treated like pickup sticks and separated?
Ok, connection. May 2019 I was thinking about pickup sticks and how crossings indicate 3D. Turned out to be a well-studied subject, which led into me discovering mathematical morphology, which I really enjoyed.
Dec 2020, rediscovered one-point perspective wireframe mazes which in the 80s were really more hotel hallways and not the narrow corridors of Minecraft (where you can also make a hotel).