Unreal Engine Issues
Unreal Engine Issues
[AI] Crash when gathering heightfield geometry on worker thread
UE - Runtime - Character - Jun 25, 2025From the body of the ticket: We aim to do as much of the work off the game thread as possible to avoid impacting frame rate. We've recently found a crash during collection of the geometry slices fr ...
The collision is wrong when the static mesh scale is set as negative value
UE - Runtime - Simulation - Feb 15, 2022I checked the c.haos code quickly. I think it caused by the function "bool FInitBodiesHelperBase::CreateShapesAndActors()". In this function, the CreateActor_AssumesLocked function will ignore the s ...
Dynamic NavMesh disappears when loading/unloading SubLevels
UE - AI - Nov 9, 2018A DynamicNavMesh within a NavMeshBoundsVolume placed in a SubLevel will disappear if loading/unloading another SubLevel that has completely nothing to do with the DynamicNavMesh. Using a setup with ...
iOS - Windows - Code projects fail to launch and package
UE - Platform - Mobile - Aug 1, 2016Attempts to Launch On to or Package for iOS fail with: LogPlayLevel: Program.Main: ERROR: AutomationTool terminated with exception: AutomationTool.AutomationException: Unabled to build Project C:/Pr ...
World Delta seconds appears to Cause a miss calculation (regression 4.12.3 -> 4.12.4)
UE - Gameplay - Jul 1, 2016If the user uses world delta seconds in a calculation there appears to be some incorrect values. Note there is also a users project attached if you would like to look at that example. ...
Can't cook a subsequent release when the project uses World Partition.
UE - Core - Data Pipeline - Cooker - Jul 14, 2026A licensee reported getting errors when cooking a subsequent release. The bug is a side effect of CL44557776 which changed the behavior when dealing with generated packages in UCookOnTheFlyServer::G ...
ComponentOverlapMultiByChannel with a rotated simple collision PrimComp misses overlap vs. complex collision
UE - Runtime - Simulation - Nov 8, 2023UWorld::ComponentOverlapMultiByChannel and internally, the call to FBodyInstance::OverlapMulti, misses overlaps and blocking hits when the PrimComp's (the component used to test overlaps) mesh uses ...
Movie Render Queue Deferred Lighting(Detail Lighting) only outputs Lighting Only
zComponent - Archive - Jun 29, 2022This is not a regression. Tested in //UE4/Release-4.27 CL#18319896 Movie Render Queue Deferred Lighting(Detail Lighting) appears to only output Lighting Only. ...
Physics Constraint Component loss of accuracy
UE - Runtime - Simulation - Mar 6, 2025Physics Constraint Component has lost accuracy between Unreal versions 5.2 and 5.4 (and up). When measuring the exact distance between rigid bodies constrained by a Physics Constraint Component, the ...
Physics actor with physics toggled will fall through static meshes set to Movable
UE - Gameplay - Jul 20, 2016Physics actor with physics toggled will fall through static meshes set to Movable User Description: Basically, what this project does is enable simulate physics on the black cube in the middle, th ...