Unreal Engine Issues
Unreal Engine Issues
Editor 'Build All Levels' discards Volumetrics Lightmaps in persistent level
UE - Graphics Features - May 14, 2025Building the level or lightmaps can clear the volumetric lightmap. In 5.5, this requires you to perform a full build, or a lighting only build with a BSP brush in the scene. In 5.6, all level build ...
ResavePackages commandlet (buildlighting) fails/asserts on reflection captures in non-visible sub-levels
UE - Graphics Features - May 13, 2025When building reflection captures through the ResavePackages commandlet, it frequently triggers an ensure inside of ReflectionEnvironmentCapture.cpp. If distributed shader builds start causing prob ...
PIE Seamless Travel with a standalone level instance causes assert in UWorldPartition::BeginDestroy
UE - World Creation - Worldbuilding Tools - Level Instances - May 8, 2025This check is hit on the server instance while it is performing garbage collection during the seamless travel. During this garbage collection, it will determine that the UWorldPartition object belon ...
Actor Channel failure occurs when quickly unloading and loading a streaming level
UE - Networking - May 8, 2025With high enough latency, quickly unloading an reloading a streaming level with a replicated actor on the server can cause the actor channel on the client to fail to find this actor: UActorChannel:: ...
Assertion failed in FNetGUIDCache::CleanReferences during seamless travel after reloading primary asset package
UE - Networking - May 7, 2025Following this sequence of events, the ObjectLookup and NetGUIDLookup on the server's PackageMapClient will end up in a bad state. In the ObjectLookup Map, the primary asset's package will be mapped ...
AssetRegistry: In a packaged game ScanPathsSynchronous with bForceRescan=true will permanently forget about assets inside IOStore containers
UE - Foundation - Data Pipeline - May 7, 2025This came up from several discussions on UDN and internal discussion. The root cause is that the AssetRegistry currently cannot discover packages inside IOStore containers, it relies on the seriali ...
UEditorValidatorBase::ValidateLoadedAsset() is not using the K2_ValidateLoadedAsset() output, effectively ignoring the Blueprint validation
UE - Framework - May 1, 2025UEditorValidatorBase::ValidateLoadedAsset() is not using the K2_ValidateLoadedAsset() output, effectively ignoring the Blueprint validation. The K2Result is not used later in the function, and this ...
Transform Origin Scale on the Level Sequencce Actor's Instance Data can affect rotations
UE - Anim - Sequencer - Apr 30, 2025Scale is used as part of the rotation calculation for transform multiplication, and it can have an effect in the sequence transform origins. It's expected that scale is completely ignored, and shou ...
Ensure triggered when creating Scene Proxy for GroomComponent
UE - Rendering Architecture - RHI - Apr 30, 2025When a room component is added in C++ via the actor constructor, an ensure is triggered from precaching and the groom component. Behavior also observed on UE5/Release-5.5, CL: 40988944 ...
ChaosWheeledVehicleMovementComponent is breaking the const CDO contract and changes to the instances are being applied to the CDO
UE - Simulation - Physics - Apr 28, 2025As described by the licensee, the const CDO contract is being broken on ChaosWheeledVehicleMovementComponent. The issue the licensee is facing is that by spawning cars with different configurations, ...