Unreal Engine Issues
Unreal Engine Issues
Destroying a welded actor is causing an Array index out of bounds crash on 5.6
UE - Simulation - Physics - Jul 30, 2025Destroying a welded actor is causing an Array index out of bounds crash on 5.6. The licensee has provided a repro project that reliably causes a crash whenever the spawned actor is destroyed. There ...
Typo in GetAsBoundsArray() from file AABBTree.h on Chaos module
UE - Simulation - Physics - Jul 30, 2025From file [Engine\Source\Runtime\Experimental\Chaos\Public\Chaos\AABBTree.h], function Chaos::TAABBTree<>::GetAsBoundsArray(): bool GetAsBoundsArray(TArray<TAABB<T, 3>>& AllBounds, int32 NodeIdx, i ...
Enabling Strip Source Data On Cook on Geometry Collection is also stripping the Anchor flag of cooked assets
UE - Simulation - Physics - Jul 20, 2025Enabling Strip Source Data On Cook on Geometry Collection (GC) is also stripping the Anchor flag of cooked assets. The licensee has reported that once they do a build the Anchors disappear and GCs t ...
Crashes after destroying a skeletal mesh attached via socket name (not bone name), the destroyed mesh remains welded.
UE - Simulation - Physics - Jul 18, 2025On welding physics bodies during primitive component attachment, UPrimitiveComponent::WeldToImplementation() calls GetRootWelded() and then GetBodyInstance() on the returned root. This searches by b ...
In AnimNode_RigidBody.cpp, PhysicsSimulation->CreateActor() is being passed World Space transforms, when it should be getting Local Simulation space transforms
UE - Simulation - Physics - Jun 24, 2025In AnimNode_RigidBody.cpp, PhysicsSimulation->CreateActor() is being passed World Space transforms, when it should be getting Local Simulation space transforms. The licensee has reported that FAnimN ...
Unexpected Collision Response When Nesting Primitive Components with auto-weld enabled and physics disabled on children. The root primitive falls through floor even though it is set to block all.
UE - Simulation - Physics - May 27, 2025Context Auto-weld makes it so if a child is attached to a parent, the two bodies will be joined into a single rigid body. Physic settings like collision profile and body settings are determined by t ...
Change of rotation axis when switching solver
UE - Simulation - Physics - Apr 17, 2025This alteration was introduced in the 'Found CL' field - and is likely an unintentional side effect of adding SIMD to the solver. There is a repro project attached, open up 'TestMap' and run to see ...
Overlay materials stop working when Show Collisions
UE - Simulation - Physics - Apr 7, 2025Overlay Materials are disabled when the Collision showflag is enabled. ...
Issue when sampling landscape height at a given location using Chaos::FHeightField::GetHeightAt
UE - Simulation - Physics - Apr 2, 2025This is an issue reported from a licensee: When sample landscape height at a given location, it is likely we interpolate from the wrong triangle. [Image Removed] Details in: [Link Removed] ...
ChaosCacheManager is not recording the Observed GeometryCollections NotifyBreak states between level loading and will default to false if changed from Record to Play
UE - Simulation - Physics - Mar 28, 2025ChaosCacheManager (CCM) is not recording the Observed GeometryCollections (GC) NotifyBreak states between level loading and will default to false if changed from Record to Play. AChaosCacheManager ...