Unreal Engine Issues

SpeedTree assets cannot be imported via Python automated import

Licensee reports via UDN that automated import via Python of SpeedTree assets does not work The issue is that USpeedTreeImportFactory::FactoryCreateBinary() tries to generate a UI dialog, which is ...

The HISM will have double drawcalls when player opens r.Mobile.AllowDitheredLODTransition

Please check the Function GetDynamicMeshElements in HierarchicalInstancedStaticMesh.cpp. The  Function Traverse in GetDynamicMeshElements will always return two Lod levels, even the transition is f ...

.mp4s cannot be played in default projects in UE5.

In UE4 (using DX11), WmfMedia was able to play .mp4 files by default. However, WmfMedia doesn't support playing .mp4s in DX12, which is what is used in UE5. Electra can handle playing .mp4s in UE5, ...

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

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 ...

Build All Levels fails with duplicate level instances

[Device Swap] - Assertion failed: AudioStreamInfo.StreamState == EAudioOutputStreamState::Closed [File:D:\build\++UE5\Sync\Engine\Source\Runtime\AudioMixerCore\Private\AudioMixer.cpp]

Issue has been seen a couple times internally and closed as No Longer occurring. Looking at Crash Reporter, issue has been seen live a number of times. Looking at user logs, occurs after:LogAudioMi ...

Memory stomp in UTexture2DArray::SetPlatformData

A crash from bad memory access can happen when clearing the textures in a Texture2DArray asset. This appears to be because the order of operations when deleting the platform data is: ``` if (Privat ...

World position offset behaves differently when setting its value directly on the result node

The world position offset input of the result node does not behave consistently. There is an obvious visual difference between the setting it by connecting a float3 color constant, versus setting th ...

Issue when turnning a character into ragdoll using PhysicsControlComp with async physics

When turnning a moving character into ragdoll, it freeze a bit with TickPhysicsAsync on. If we log the character's pelvis position, it seems jump backward in the first few ticks. Also, it only happ ...

Building Geometry Stops UTickableWorldSubsystem Ticking

Can be mitigated by reopening the Level. There is a repro project provided by the licensee on the case ticket. ...