UE4 NVPhysX branch 404 error

Hi, I am currently developing a game based on UE4 Flex since there is no alternative for soft body physics in UE5 Chaos. I was using the branch from https://github.com/NvPhysX/UnrealEngine/ but for some reason I am not able to access this repos anymore as I am getting a 404 error even though I can access the EpicGame branch of UE successfully . Could you help me reach this repo? Thank you very much

Hi @Sephiroth_FF !

I am really sorry for this inconvenience. The only thing I can share for now is that there are technical issues with this particular Github repo of NVIDIA since last weekend. We are working on a solution for this, but we don’t know an ETA yet.

For now please use your latest cloned or downloaded version of the repo. If you don’t have a local copy please send me a DM and I will check what I can do.

I will try to follow up with an update as soon as public access is restored.


Hi @MarkusHoHo, Thank you so much for your response. I can definitely work with my currently cloned version of Flex. I got worried that since Nvidia has deprecated support for these branches, that they where being taken down permanently. Glad to hear they will be back eventually.

While all the other GameWorks tech have had alternatives by mainline UE5.1, Flex is currently the only soft body physics for Unreal with support for advanced skeletal mesh interaction and GPU acceleration. Really wish NVIDIA could make a exception for Flex and port it to 5.1 but, I understand it might not be feasible with all ressources needed for the maintenance of NvRTX branch.

Thanks again!

Hi folks, just wanted to follow up on this to ask if NVPhysx repo access will be restored?
I was relying on this branch for UE engine builds as it’s often updated quicker and sooner than NVRTX, so be good to know if it’ll be coming back.

I am sorry, but I don’t have any good news yet.

It seems it is a more complicated than technical issues since GitHub changed some of their service agreements for companies. Sorting through this might take a bit longer I am afraid.

Have there been any updates since January for accessing the NVPhysX repo to use with the Unreal Engine? Is there an alternative location that could be considered?

Hello @toasticuss ad welcome to the NIVIDA developer forums.

Thank you for coming back to us about this.

I am afraid that at this time there is no plan to (re-)open a separate PhysX repository beside the one that is part of Omniverse.

But the Omniverse one is also more current and has the latest and greatest.

I hope that helps!