Unreal Engine Issues
Unreal Engine Issues
Chaos Fields: LS_MasterField continuously creates components every frame and never cleans them up
UE - Simulation - Visual - Mar 25, 2026While active and ticking, the built-in FS_MasterField actor instance continuously creates several new components every frame, which are never cleaned up until the actor is destroyed. This can happen ...
LevelStreamingPersistence: BP added components don't persist properties in PIE until map actor resave
UE - World Creation - Worldbuilding Tools - Mar 6, 2026Context The LevelStreamingPersistence plugin can be used to remember and restore properties on actors, components and other objects that are part of a streamed level. Persisted properties are resto ...
Missing logging or error when applying an anim instance to a skeleton that the anim instance doesn't match.
UE - Anim - Runtime - Feb 9, 2026Currently, we detect whether an anim instance is supported by the skeletal mesh and, if it isn't, unreference the instance, but we don't error or warn the user that this happened. This leads to conf ...
SaveGeneratedTexture2DAsset can crash when overwriting an existing asset
UE - Texture - Nov 28, 2025SaveGeneratedTexture2DAsset can crash for a variety of reasons when overwriting an existing texture asset. When no existing asset exists, the function simply moves the provided transient Texture ass ...
Ray tracing scene doesn't reflect WPO with instance custom data
UE - Rendering - Graphics Features - Ray Tracing - Sep 19, 2025When custom instance data is used to calculate WPO in a Material and applied to an ISM the WPO value in the Lumen scene (ray tracing scene) is different than the visible scene resulting in incorrect ...
Sphere Mask ArgInvHardness missing multiplication
UE - Rendering - Architecture - Materials - Jun 27, 2025Hi Epic, In MaterialExpressions.cpp UMaterialExpressionSphereMask::Compile(), hardness is not calculated the same way in both <if> conditions. One is missing a multiplication by 0.01f. Specificall ...
Interchange Runtime .glb Import Crash When Packaged
UE - Editor - Content Pipeline - glTF - Jun 10, 2025The runtime import process works fine in editor, but fatal error when trying to do so with packaged build of project. My function that calls ImportAsset():bool UMeshLoader::RequestMeshLoad(FString ...
Multiple setter functions in UMaterialEditingLibrary always return false even when the parameter is correctly set on the MaterialInstance.
UE - Rendering - Architecture - Materials - May 30, 2025In Unreal Engine, materials can expose parameters that can then be modified via instances (MaterialInstanceConstant). The UMaterialEditingLibrary provides several functions to modify these parameter ...
Search field in 'Quickly Add to Project' fails with Chinese Pinyin input unless manually focused
UE - Editor - UI Systems - Localization - May 28, 2025A licensee reported that under the Chinese language setting in UE5, using the “Quickly Add to Project” button results in incorrect or ignored input when entering text via Pinyin IME. If the user sta ...
ChaosWheeledVehicleMovementComponent is breaking the const CDO contract and changes to the instances are being applied to the CDO
UE - Simulation - Gameplay - Apr 28, 2025As described by the licensee, the const CDO contract is being broken on ChaosWheeledVehicleMovementComponent. The issue the licensee is facing is that by spawning cars with different configurations, ...