Unreal Engine Issues
Unreal Engine Issues
Fbx importer can import valid under 30Hz anim at 30Hz
Tools - Jul 17, 2017The samplerate of a track was compute with the following formula Equation 1: number of Key / animation Time This formula work only if we have animation keys that are time equidistant. example of ...
Surface Profile Skin shading has some unexpected stripe rendering issues
UE - Graphics Features - Apr 3, 2018So it looks like the artifact is definitely related to whether sss checkboard is enabled, but I can't reproduce it if enabling checkboard right after open the map, I mean it has to be reproduced aft ...
Incorrect Lumen Scene direct lighting when objects behind masked landscape
UE - Rendering - Features - Lumen - Oct 5, 2025When objects are placed behind or beneath a masked landscape and r.Lumen.HardwareRayTracing.SurfaceCacheAlphaMasking is enabled, the direct light evaluation is incorrect. There are two workarounds, ...
Non-determinism in StaticMeshComponent::BodyInstance when cooking LevelInstances
UE - Runtime - Simulation - May 21, 2026A licensee reported that serialization of LevelSequence with StaticMeshActor with default collision for which mesh has NoCollision profile is not deterministic. The issue seems to be in the fact tha ...
Crash when saving a Data Table that is referencing itself in a Data Table Row Handle
Tools - Feb 23, 2017Crash when saving a Data Table that is referencing itself in a Data Table Row Handle. Reopening the project also causes a crash. *Regression: Yes This was fixed and working in 4.13-3037605 This i ...
Widgets With Retainer Boxes Are Selected When Behind Widgets Without One
UE - Editor - UI Systems - Dec 24, 2019When a widget that has a retainer box is behind another widget that doesn't have one it will call it's onclick instead of the one in front of it in the UMG when clicked (see attached gif). This beh ...
Simulated physics bodies not working properly with BP Move Component To node
UE - Simulation - Physics - Jun 5, 2015This issue may reference [Link Removed] which was recently fixed with 4.9 CL-2553675. When using the MoveComponentTo node physics do not work properly compared to other methods to move a component ...
BulkData Async loading remains in memory
UE - Foundation - Core - Oct 26, 2016Gil's new loading path may already walk away from this issue. But here's some thing I tested locally if we want to fix this. A simple way to fix is to simply add BulkDataAsync.Deallocate(); ResetA ...
VC Runtime not in UnrealLightmass temp directory; causing lightmass build errors
UE - Foundation - Cpp Tools - UnrealBuildTool - Oct 14, 2015A Redistribute file for VS 2015 is needed to build lightmass, but this is not currently included with the engine. If a user does not have VS 2015 installed, lightmass will fail with this error: Un ...
Different instanced materials are seen as the same material due to GUID
UE - Rendering - Features - Jun 3, 2021See licensee description of the issue: The problem appears when I have two instanced materials with the same number of parameters. I've noticed that ShaderMapId has MaterialLayersParameterIDs where ...