Unreal Engine Issues
Unreal Engine Issues
Unreal Header Tool can sometimes fail if an Engine plugin is Enabled By Default and has the "Program" Module Type set
UE - Foundation - Core - Feb 15, 2018An Engine plugin with the Program module type and EnabledByDefault set to true can cause the Engine to fail to build successfully due to UHT failing. I was only able to reproduce this behavior using ...
For a TMap with C++ enum keys, deleting and re-adding a map entry in the Editor can corrupt the map data.
UE - Editor - Jul 19, 2024When adding an entry to a TMap using UE's property editors, in most cases the new entry comes with a default-initialized key (if such key already exists, the insertion fails). The case of a UENUM de ...
Renaming a Blackboard Key removes it's references in the Behavior Tree
UE - AI - Jan 27, 2015Renaming a Blackboard Key removes it's references in the Behavior Tree ...
StructUtils plugin's `FInstancedStruct` in a CPP-defined struct in a `TArray` on an actor component defined in CPP and implemented in BP. Populating the instanced struct in an actor BP's class defaults breaks serialization of the class defaults.
UE - AI - May 30, 2025Context Instanced structs are great for holding simple data with the main advantage they have is a low memory overhead unlike instanced objects. Problem The problem is in StructUtils plugin's `FIns ...
Crash with for loop and TArray in constructor to generate multiple StaticMeshComponents
UE - Foundation - Core - Apr 20, 2015Using a TArray to store multiple components being setup inside a for loop of a constructor will crash on project open. Crash Reporter: [Link Removed] ...
Make Bitmask node returns incorrect value when using custom Enum
UE - Gameplay - Blueprint - Jul 5, 2016When a custom enum is used as the Bitmask Enum of a Make Bitmask node, the value returned does not match the expected value ...
Mover Plugin: UNavMoverComponent::GetFeetLocationBased() returns incorrect FBasedPosition when using WalkingMode over a Movable floor, making UPathFollowingComponent erroneously detect a blocked move
UE - Runtime - Character - Nov 12, 2025Function UNavMoverComponent::GetFeetLocationBased() on file "NavMoverComponent.cpp" returns an FBasedPosition built from an FRelativeBaseInfo. The "MovementBaseInfo" is read from key "CommonBlackboa ...
UE5.6+ - Mutable - IDPrefix crash when combining Child Objects, Add to Mesh Component and Extend Mesh Section.
UE - Anim - Mutable - Jul 21, 2025So the issue seems to be a combination of Add To Mesh Component and Extend Mesh Section. I've tried this in Epic Launcher 5.6, 5.6 in-house modified engine as well as ue5-main 5.7 from git (editor ...
Regression: Cannot import Landscape Layer Weightmap along with Heightmap because of broken resolution check for tiled images.
UE - Graphics Tools - Terrain - Jan 30, 2025When working in the "Landscape" editor mode, in both the "New" and "Import" tools, it is possible to import a single heightmap, as well as a weightmap for each layer. Each of these maps can come fro ...
Niagara crash when using a particle attribute reader that has been passed around between modules
UE - Niagara - Oct 28, 2025The following Niagara usage pattern results in either a crash or in incorrect data being read from a Particle Attribute Reader: Emitter Spawn Stage – A module has an Attribute Reader input specifie ...