Unreal Engine Issues
Unreal Engine Issues
Rect lights cause visual noise on the light rendered when using raytracing
UE - Graphics Features - Lumen - Nov 12, 2019Rect lights cause visual noise on the light rendered when using raytracing. It is easier to see when you get rid of all other light sources in the scene. I have attached an example project. This se ...
InvariantLeft and InvariantRight justification mispositions wrapped multi-line text
UE - AI Workflows - UI Systems - Feb 26, 2026When a UMG Text widget is set to Auto Wrap and uses InvariantLeft or InvariantRight, the wrapped visual lines are positioned differently than expected compared to Left/Right. In the current engine ...
When move selected foliage to level, Foliage can not move to level.
UE - World Creation - Worldbuilding Tools - Foliage - Jul 18, 2017With 4.15, I can move Foliage to "Sublevel B", but I can not move it with 4.16. It seems to be affected by the update in 4.16 (New: When moving a foliage asset to a new level, you will now be prompt ...
Steam Overlay does not show in Win64 Shipping builds when run outside of Steam
UE - Networking - Nov 11, 2015Steam Overlay does not show in Win64 Shipping builds when run outside of Steam. The Steam client can be running, but unless the .exe is opened through Steam itself, the Overlay will not appear. Note ...
Certain Projects crashes on Start AR on iOS
UE - Platform - XR - Jun 11, 2025Repro rate 5/5 Project crashes on pressing "Start AR" in ARDebugCheck, on "Begin Scan" in Handheld AR Template and on "Start AR" in ARImageDetection. Issue also occurs on ARVideoSettings and ARSave ...
Enum with "MAX" element at other than the last element removes user defined last element
UE - Foundation - Core - Oct 18, 2019FNativeClassHeaderGenerator::ExportEnum produces this behavior. If an enum has “MAX” somewhere in the array, it removes last element. I tested my code to fix the issue.// code placeholder bool UE ...
Clothing Data Cannot Be Created If The Old Data Was Deleted While Applied
UE - Simulation - Physics - Character - Jan 16, 2020When you delete clothing data on a skeletal mesh before removing it you cannot apply new clothing data. The engine still thinks that there is clothing data is applied. I tested using the Paragon: Tw ...
Alembic Geometry Cache is corrupted on reopening of project leading to crash
UE - Foundation - Core - Dec 20, 2016Alembic Geometry Cache crash when re-opening the project and a map that contains this asset or adding it to any existing/new levels will instantly crash the editor. This asset works correctly in the ...
Window to select Skeletal Mesh does not pop up when editing a new IK asset
UE - ACT Character - Retargeting - Apr 26, 2023When opening a new IK rig, the window that prompts the user to select a skeletal mesh does not open immediately. However, a skeletal mesh can still be selected in the details panel in the IK window. ...
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, ...