Yeah that’s not great. It exposes a couple issues we have at the moment (and maybe some we don’t know about) that we will address. I don’t have a timeline except to say that stability is very important to us and we’re continuously working on it. I just created a sample like this in our sandbox so at least we have a test case now.
The issues I know about are
- We shortcut collision detection when things don’t move much and it looks like it doesn’t work well in this case. I need to investigate this to figure out why (we need this for performance) but in the meantime there’s a console variable to disable this system
- We reduce the number of contacts between two shapes to 4 points and it looks like we are constantly switching contact points for large discs like this. This prevents the system from ever settling down. Needs further investigation.
- We have a shock propagation system to stabilize stacks but it doesn’t work well when all objects are lying sideways and overlapping domino-style.
p.Chaos.Solver.Collision.AllowManifoldUpdate 0