Collision between physicalized actors and instanced static meshes produce warnings.

UE - Simulation - Physics - Sep 25, 2023

Collision between an instanced static mesh and a physics simulating actor (with "simulation generates hits events" enabled) results in the following warning: LogChaos: Warning: Collision handler en ...

Spherecast against complex geometry is returning odd results

UE - Simulation - Physics - Sep 19, 2023

Turning on batching of sphere casts when colliding against complex gives incorrect results. Affects debug output and vehicle wheels and body movement. The issue is with the batch query mode which ...

Deadlock in UPhysicalAnimationComponent::UpdatePhysicsEngineImp

UE - Simulation - Physics - Sep 13, 2023

Deadlock in Chaos during PIE; the main thread is in USkeletalMeshComponent::HandleExistingParallelEvaluationTask waiting for a task to complete, and a worker thread is running that task and is in US ...

Free physics constraints between two objects of differing size causes smaller object to jitter

UE - Simulation - Physics - Sep 13, 2023

A cube constrained to a physics actor will start to jitter uncontrollably when interacted with. (see attached media and repro steps for more details) Tested in the following //UE5-Release-5.3-CL ...

Unable to set simulate physics to false through blueprints

UE - Simulation - Physics - Aug 24, 2023

If "Editable when Inherited" is disabled for the static mesh component the issue does not occur. The bug could be related with other UDN cases:https://udn.unrealengine.com/s/case/5004z00001ruXmEAAU ...

When change a skeletal's collision from QueryOnly to QueryAndPhysics at runtime, dynamic properties won't be updated

UE - Simulation - Physics - Aug 23, 2023

It seems in the FBodyInstance::InitDynamicProperties_AssumesLocked, we early out when the body instance's collision is QueryOnly, but actually we only recreate its physics state when changing from N ...

Geometry collection - source geometry not updating and reset bug

UE - Simulation - Physics - Aug 17, 2023

This issue was reported by a customer trying to modify the static meshes of a GeometryCollection. After removing some meshes from the Geometry Source, he used the Reset button to apply the changes t ...

Cannot change collision presets in BP instances.

UE - Simulation - Physics - Aug 8, 2023

Even with the “Editable when Inherited” flag set in the blueprint class static mesh component, the BP instance collision preset cannot be set to one different from the BP class collision preset. The ...

Mesh deformed by Cable Component does not output velocity

UE - Simulation - Physics - Aug 7, 2023

The velocity when moving the root is output, but it seems that the velocity for each deformation is not output. Since motion blur and TSR use velocity, problems such as ghosting may occur. ...