Unreal Engine Issues
Unreal Engine Issues
Section::TrimSection resulting in bad key values at start and end of trim range
UE - Anim - Sequencer - Dec 17, 2025The trim process inserts keys at the start or end of the range depending if you specify Trim Left or Right, I'm finding that Trim right is inserting a key at the end of the section that is incorrect ...
ActorComponents registered with wrong world from UWorldPartition::ApplyRuntimeCellsTransformerStack
UE - World Creation - Worldbuilding Tools - World Partition - Dec 17, 2025There is a risk of actor components registering with the wrong world when reconstructed from UWorldPartition::ApplyRuntimeCellsTransformerStack. The repro case is arguably a bad usage, but it was th ...
Viewport stuttering during orbit/zoom navigation
UE - Graphics Features - Dec 17, 2025Received a report of persistent stutters in the editor when trying to navigate in the viewport, including asset editor viewports like the Skeletal mesh editor and control rig editor. Hardware used ...
Disabled Skeletal Mesh Sections cause Shadow Ray Tracing Flicker
UE - Graphics Features - Ray Tracing - Dec 12, 2025If a skeletal mesh has a section disabled the ray traced shadow will flicker when the camera or itself moves. Previously in 5.6.0 no raytraced shadow would appear if a section was disabled. This wa ...
[3ds max] Some geometry will display in all black in Path Tracer renders
UE - Editor - Content Pipeline - Datasmith - Exporters - Dec 12, 2025Reported in SF [Link Removed] Some geometry from 3ds Max will display as all black when viewed in Path Tracer rendering. This effect is visible in both UE and Twinmotion. This was tested with Data ...
Iris - Ensure hit when destroying a torn off actor from AActor::TornOff
UE - Networking - Iris - Dec 11, 2025As of CL 42014318, StopReplication requests that occur during ReceiveUpdate are delayed until all received data from the update is finished processing, including if the actor is torn off. However, i ...
PCG sampling of RVT does only works when sampling the first texture layer
UE - World Creation - Procedural Tools - PCG Component - Dec 11, 2025The logic for selecting a page table texture in FVirtualTexturePageTable::Initialize() uses the indexing for texture layers (index 0-7) to fetch from the page table textures (index 0-1). All RVT for ...
VirtualTextureStreamingPriority cannot be set per TextureLODGroup
UE - Rendering Architecture - Dec 11, 2025It is currently not possible to set a VirtualTextureStreamingPriority via the TextureLodGroups that are defined in a device profile. ...
[ALT] - UE56 Editor launched with -AsyncLoadingThread will trigger MTAccess
UE - DEET - EditorLoader - Dec 10, 2025When launching the editor with the -AsyncLoadingThread command, the engine uses an asynchronous thread to load and instantiate UObjects. At this point, if the instantiated UObject contains an FData ...
Replicated timeline may not call Finished event on client
UE - Networking - Dec 9, 2025It seems this can happen if the timeline component on the client receives an update from the server for the final position of the timeline, causing it to be set as no longer playing before it has a ...