Unreal Engine Issues
Unreal Engine Issues
Dynamically Spawned Level Instance Actors do not have their sub actors world partition stream in PIE starting level
UE - World Creation - Worldbuilding Tools - Level Instances - Jun 10, 2025We are building levels where we spawn in Level Instance actors at runtime that have World Partition enabled into a Persistent level that also has World Partition enabled. What we have noticed though ...
Skeletal mesh to which the AnimationBudgetAllocator registered in the animation track is applied does not play the initial frame animation
UE - Anim - Runtime - Jun 10, 2025This issue occurs when “Auto Register with Budget Allocator” is enabled for the skeletal mesh. Unchecking “Auto Register with Budget Allocator” seems to resolve the issue. Adding the following to th ...
Editor vs Runtime: Inconsistent data layer behavior when attaching actors
UE - World Creation - Worldbuilding Tools - World Partition - Jun 5, 2025In editor, data layer system respects the data layer settings for each actor, but at runtime, the condition check is made collectively for each actor cluster, resulting in differences in behavior. ...
Editor crashes when using PCG SpawnActor with a DataLayer inside a Level Instance
UE - World Creation - Procedural Tools - Jun 4, 2025A PCG actor is assigned to a DataLayer and placed inside a Level Instance. Then that Level Instance is placed into a World Partition map. When the SpawnActor node in the PCG graph is set to MergePCG ...
ChordBlockers don't work as expected when ChordAction is set in InputAction
UE - Gameplay - Input - Jun 3, 2025In the Enhanced Input System, when using a UInputTriggerChordAction to define a chorded input (e.g., Shift + W), the automatic chord blocking system (UInputTriggerChordBlocker) only functions correc ...
Local lights appear broken when baking lighting with GPU Lightmass
UE - Graphics Features - Jun 2, 2025Encountered an issue where local lights appear to be broken when baking lighting with GPU Lightmass. See screenshots attached. Tested regression in //UE5/Release-5.5 @ CL40574608 and the issue does ...
Virtual Bone caused nanite skinned mesh crash
UE - Graphics Features - Nanite - May 31, 2025When a Nanite skeletal mesh has a virtual bone the engine can crash when changing LODs ...
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 ...
GPU Lightmass no longer works with cascaded shadow maps
UE - Graphics Features - May 29, 2025Since Unreal Engine 5.5 stationary lights have stopped working with GPU Lightmass when using Cascaded Shadow Maps. With Virtual Shadow Maps enabled on the project, GPU Lightmass works. This issue d ...
VSM SMRT SamplesPerRay CVars behave differently if groom assets are present leading to a potential full-scene shadow
UE - Graphics Features - May 28, 2025When a groom is present, setting any SamplesPerRay SMRT CVar to zero results in an unexpected complete shadow projected from the light. ProjectLight() in VirtualShadowMapProjection.usf has addition ...