The two main uses where “cylinders” are needed rather than just well tesselated convex hulls, or box stacks, is:
- Barrels. Best work-around is to use a capsule, and stick a box on the inside that doesn’t go outside the barrel walls. The box lets it stand on flat ends; the capsule lets it roll when knocked over.
- Wheels. This is for car physics. Generally, using boxes for side collisions, and using ray casts for wheel/suspension/contact/friction, will let you get far enough.
I wonder what the Chaos vehicle use for its wheels?