Unreal Engine 4.26-Chaos Preview now available on the Epic Games launcher

Preview 2 takes 10 minutes for each of; Applying clothing data, activating cloth paint, painting on cloth. I’m trying to simulate clothing for a character- The simulated clothes are around 25k tris.

edit: It is manageable with less tris, almost 17k now- need to still wait for 1-2 mins when making changes.
There is also a problem with self collisions jittering and spiking when enabled.

We also experienced these same issues 3-4 months ago, and disabled Chaos for now.

When I try use ragdoll (simulate physics for skeletal mesh) with box shapes on the hands and foots, box shapes constantly get some impusle, and body always try to fly into the space =)
If I replace boxes on capsules, it will works fine, and impulses do not attack the body. I think, you must know about it =)

Chaos in 4.26 Chaos P2 is OK. When are you going to make it part of 4.26?

The link on how to configure the project is broken. I think How to configure the Chaos Destruction Demo for the 4.26-Chaos Preview is the correct link.

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We have just released Preview 3 for 4.26-Chaos! Thank you for your continued help in testing the 4.26-Chaos build before its official release. As a reminder, the Preview builds are for testing only, and should not be used for the active development of your project.

For a list of known issues affecting this latest preview, please follow the links provided on the first post in this thread.


Fixed in 4.26-Chaos Preview 3

UE-108256 Capsule Inertia Tensor does not seem to account for the axis transform of the capsule

UE-104908 Crash on triggering RadialForceActor with WorldStatic component on “ce Impulse” stand

UE-104817 Chaos Fractured Geometry Collection Crashes after Fracture

UE-104412 Chaos Geometry Collection with several cluster fracture levels breaks prematurely

Confirm, link broken.
In 4.26 Chaos p3 version Chaos Demo not working, after fail rebuilding…

I still have performance problems with chaos, creating an empty project and adding 150 cubes with active physics simulation in the chaos, I can get 20 fps and physx 120+ fps

I still have performance problems with chaos, creating an empty project and adding 150 cubes with active physics simulation in the chaos, I can get 20 fps and physx 120+ fps

Problem still exist on master brunch too.

Why I dont see the 4.26-Chaos in my Epic game launcher?

I’ve been trying to use Chaos Vehicles with the Preview 3, but I can’t get them to move.

I’ve tried creating them from scratch, converting some existing vehicles to their chaos counterparts and have even tried a vehicle plugin from the marketplace which is built on a custom C++ class derived from Pawn so that it is not related to specific engine vehicle physics plugins.
They simply don’t react to inputs when I try to throttle, brake or steer, the wheels don’t even turn.

The fun fact is that if I press any input when they are spawned at begin play, being dropped mid-air and falling to the ground, then they start moving backwards very slowly after touching the ground. They will continue doing so until I brake, then they stop and can’t move anymore.
Something seems to be broken with torque and rotation physics in general.

I’ve read from a few people on answerhub and reddit that vehicle physics are broken since preview 2 or 3. Does anyone have any experience on this?

You can find it at the bottom of the dropdown list when choosing the engine version to install.

In the page How to Set up Chaos Vehicles | Unreal Engine Documentation what does it mean when we read “This plugin will not work with PhysX enabled”?
Does it refer to the Physx Vehicles plugin that must be disabled or to something else?
The 4.26Chaos build is compiled with WITH_PHYSX=1.

So on first run of ue5 in a c++ project I get a warning in vs2019

1>’“D:\UE5\UE_5.0EA\Engine\Build\BatchFiles\GetDotnetPath.bat”’ is not recognized as an internal or external command,
1>operable program or batch file.

hope you guys can fix that.

I tried migrating a 4.26 project. It gets to 75% loading and says:
“The game module ‘projectName’ could not be loaded. There may be an operating system error, the module may not be properly set up, or a plugin which has been included into the build has not been turned on.”

Is there something I need to add to the uproject file or somewhere in the .cs files?