Unreal Engine Issues
Unreal Engine Issues
Map actor reconstruction does not reattach external non-root components
UE - Framework - Components - Jan 17, 2024For two map placed actors, if one actor B's non root component is attached to another actor A, the attachment is not retained when actor A reruns its construction script, such as when moving actor A ...
When importing static mesh using interchange and collision is generated, the asset does not have Collision Generated set to true
UE - Editor - Content Pipeline - Import and Export - May 19, 2025Context: The Interchange Framework is Unreal Engine's import and export framework. When importing a mesh without collision, collision can be auto-generated. Problem: The problem is when importing s ...
Random Number Generated in Constructor Returning Different Value on Begin Play
UE - Gameplay - Jan 13, 2016When generating a random number using FMath::RandHelper() in the constructor of an actor, attempting to print that same number on BeginPlay returns a different value than the constructor. However, ...
D3D validation error about resources being deleted while in use
UE - Rendering Architecture - RHI - Jun 7, 2022We believe this is a bug in the D3D validation layer, rather than an actual error in our code. We're in touch with Microsoft about it, but I'll make this ticket to track the progress of that investi ...
Lidar Point Cloud Plugin functions return empty locations for individual points (both relative and world scale)
UE - Editor - Content Pipeline - Feb 21, 2025The locations of individual point cloud points are empty in the array returned from the get_points_in_box_as_copies,get_points_in_sphere_as_copies,line_trace_multi functions. The last boolean argum ...
Cook non-determinism when serializing UObject pointers pointing to garbage
UE - CoreTech - UObject - Aug 25, 2025There's a cook determinism issue in the way UObject unversioned serialization handles UObject pointers pointing to garbage. Depending on GC timing, it can either be skipped (as a property matching C ...
Override Attenuation Can't be Unchecked When Audio Component Added to Blueprint and Blueprint Attached to Actor
UE - Audio - Dec 20, 2017Checking Override Attenuation in Details < Audio Component < Attenuation disables settings that further adjust the Attenuation. Such as: Attenuation Air Absorption, Attenuation Listener Focus, Atte ...
Server RPC with struct param containing class reference does not pass parameter
UE - Networking - Apr 2, 2018Class ref is not passed to server within the struct in UE 4.19. Instead, the default value is passed to the server. LogNetPackageMap: Warning: SanityCheckExport: CacheObject == NULL. NetGUID: 1, Ob ...
Renaming a level by WorldPartitionRenameDuplicateBuilder fails if the level contains GroupActor with non-spatial actors
UE - World Creation - Worldbuilding Tools - World Partition - Oct 24, 2023Referece to the source level should be fixed by FReplaceObjectRefsArchive, but it is not working because ArIsModifyingWeakAndStrongReferences is not set. It can be fixed by setting the flag.class FR ...
FAnimationRuntime::BlendPosesPerBoneFilter() causes an assertive crash when Skeletal Mesh LOD is changed
UE - Anim - Runtime - Nov 1, 2023The crash occurs from "check(BoneBlendWeights.Num() == NumBones);" This crash occurs when the following conditions are met;The skeletal mesh LOD is changed.The number of bones is difference between ...