preist-nvidia
commented
3 months ago Your intuition is correct, the solver will struggle with resolving this collision. I assume the vehicle was moving fast when the locking penetration occurs?
Did you try and increase contact offset on the car or block shapes?
Internal tracking: PX-4882
Hi there,
I have a vehicle that has an aggregated (composite?) collision made from various spheres, capsules and boxes. In certain circumstances, mostly when a lot of collisions with other objects are taking place, I can get into a state where a large object is stuck inside my vehicle collision and doesn't get resolved out of it.
Here is a screen grab from a pvd capture. The large box sticking vertically up is the collision on a block that is stuck inside my vehicle's collision.
I have disabled all contact modifications I have in our project and anything else that might be injecting forces/impulses/velocities etc into the simulation.
The issue occurs with and without a max depenetration velocity set.
The issue occurs with or without CCD enabled on the collision.
The issue does not occur if I have a single convex collision shape for my vehicle instead of the aggregated collision.
We are using physx through Unreal Engine 4 and are on version 3.4.
Please could you give some advice on why this occurs and what my options might be to avoid it?
I need my composite collision (I am deforming it) so I can't just replace it with a single convex shape.
My feeling is that the physics steps must be trying to resolve the penetration but with so many bodies around it can't iteration to a solution with the block body outside of my vehicle collision. Is this plausible? If not helping to understand why this happens might help me formulate a workaround.
I am going to try adding an extra body that just collides with things like the block that is a single convex shape. I hope that resolves the issue.
Thanks in advance,
Phil