Hi,
I am currently doing some testing with the chaos physics system in UE5 early access.
While performance is generally fine with simulated meshes with simple colliders( box or sphere collider) when simulating meshes using a bunch of convex shapes the performance suffers extremely.
I made a test blueprint that spawns 125 simulated actors using 8 convex shapes in a grid with random rotations and I observed the performance as they drop to the floor. I know this is not a typical gameplay situation but in UE4 4.26.2 with PhysX this runs without a hitch on my Ryzen 9 5950X. In UE5 early access the same simulation setup causes my whole engine to freeze and then take over 100ms per frame. The freezing happens even before the actors hit the floor.
I am developing a VR game where physics actors need a rather precise collision shape, so convex shapes are needed. Is there a reason for why simulations with them perform so terrible? Am I missing a magic setting? I tried a bunch of configurations as well as the async scene but nothing changes.
I really hope that this improves drastically in the future because in this form I could never use it to develop my game. And I know this is still early access but chaos has been around for a while now and I don’t see it improving in that regard