Hi.
It seems like UE5 physic cloth simulation is really slow. I’ve tried to do the same process in UE4 which is 10x faster in performance. What I mean by the process are cloth painting and physic capsule adjustments.
Does anyone know how can I optimize the performance in UE5 when doing the cloth painting?
Thank you.
Did you find a solution for this?
No.
But from what I understand that UE4 uses Nvidia apex cloth physic while UE5 uses chaos physic simulation.
From the point of view, chaos physic has a better quality than apex when it comes to physics simulation, but with the price of performance. It gets worst when you have tons of vertices to be calculated per frame.
So, yeah UE5 is very intensive in performance. I don’t have the best computer for the chaos physic to simulate it, so I just turn it off and make an artificial (fake) physic myself.
Thanks for answering. Believe me, its something they have to work on enhancing in terms of cloth simulation performance, or maybe someone familiar with that can answer us both. My computer has 128GB RAM and I use RTX4090 but it still performs that dance and breaks up while playing cloth, and I am talking about for example the scarecrow in the medieval village environment they did using UE4.27 
Chaos is just 50 to 75% worse performance than PhysX. Period.
At this point I think they demonstrated that they won’t be addressing any performance issues with it.
It’s been years since the first beta, and years where the user base has constantly pointed out the massive performance loss from it. They wholly ignored it for years.
Their response has actually been to make it even harder to purge chaos out of a custom engine build to go back to physx.
If you need an engine with decent performance (even graphics), move on to something else.
CryEngine with paid Havok will work ok for large projects which can afford it.
UNITY offers a cheap version of havok too.
Unreal meahwile, has to be custom built with an older physx. And loose/miss out on a bunch of UI in versions above 5.
I don’t think it supports Havok any longer, since the system is essentially no longer modular when attempting replacement (ofc, if you pay for it, they likely give you a working source to build the engine with their physics, I hope).
Its kind of a mistery how the fortnite id10tcommunity hasn’t gone up in arms over the 5 to 15fps drops from rendering, and the additional unquantifiable drop from the chaos switch over. However unless their sales drop by 50% from it, epic will never care about any issue…