Unreal Engine Issues
Unreal Engine Issues
Distance Field Shadows do not work with Nanite meshes
UE - Rendering - Graphics Features - Nanite - Feb 16, 2026Nanite meshes only cast virtual shadow maps and do not cast any distance field shadows, regardless of the distance of the shadow casting mesh to the camera. ...
CPU Lightmass generates different lighting results on a landscape if executed via a commandlet vs through the editor
UE - Graphics Features - Jul 3, 2025Building lighting via commandlet and via editor are giving different results. To prevent one method from polluting the other via Swarm cache, the cache needs to be cleared in between tests. ...
Navigation: Exiting game while async nav building tasks are running can cause null pointer access of OctreeController.NavOctree from worker thread
UE - AI - Navigation - Nov 1, 2024Context Projects can turn on the project setting bDoFullyAsyncNavDataGathering to execute navigation mesh building tasks on worker threads. Some of these tasks will access the NavOctree, whose life ...
Navigation: Exiting game while async nav building tasks are running can cause null pointer access of OctreeController.NavOctree from worker thread
UE - AI - Navigation - Jan 14, 2025Context Projects can turn on the project setting bDoFullyAsyncNavDataGathering to execute navigation mesh building tasks on worker threads. Some of these tasks will access the NavOctree, whose life ...
Crash in UDataTable::RemoveRow(FName RowName)
UE - CoreTech - Jun 13, 2025This is a regression, the crash seem to have been introduced by CL 40129784 on ue5-main and persists in latest. Function UDataTable::RemoveRow(FName RowName) uses macro DATATABLE_CHANGE_SCOPE_SINGL ...
FileSystemDerivedDataBackend may output a corrupted access log
UE - Foundation - Core - Derived Data - May 20, 2021This problem is caused by the AccessLogWriter has not been flushed at the termination. The following workaround flushes the Writer.class FFileSystemDerivedDataBackend : public FDerivedDataBackendInt ...
Hot reload can prevent code components from being accessible in blueprints
UE - Foundation - Cpp Tools - Hot Reload - Sep 29, 2017When a class is edited / hot reload preformed, code based components are sometimes removed from the MyBlueprint > Variables section and cannot be dragged from the Components tab into the graph with ...
GAS PlayMontageAndWait: Server applies root motion with wrong scale at last montage tick
UE - Gameplay - Gameplay Ability System - Apr 3, 2024User reported: when playing an AnimMontage via GameplayAbility with the PlayMontageAndWait ability task that has a custom value for AnimRootMotionTranslationScale, (dedicated) servers can apply an i ...
Damping is handled differently at lower frame rates
UE - Gameplay - Aug 3, 2016Damping is handled differently at lower frame rates. Slight changes in damping at lower FPS (25) drastically effects objects and isn't applied in the same way as at higher FPS (60) User Description ...
Creating a float variable named lifespan in an Actor Blueprint and setting its default value will override the life span of the parent class
UE - Gameplay - Blueprint - Dec 19, 2016Creating a float variable named lifespan in an Actor Blueprint and setting a default value for it will override the parent class' life span setting. I was unable to find any variable in the Actor cl ...