Unreal Engine Issues
Unreal Engine Issues
Switching modular control rig to FK mode breaks pose of controls that have been baked to rig
UE - ACT Character - Control Rig - Sep 14, 2025From the licensee:We have built a modular Control Rig in Unreal 5.6, and while IK to FK matching works correctly inthe rig, but we are facing an issue when applying mocap animation to the characters ...
Crash when calling FillDataTableFromCSVString() while viewing the contents of the data table
When the function UDataTableFunctionLibrary::FillDataTableFromCSVString() is used from Editor Utility Blueprints or Python Scripts, and the contents of the affected Data Table are currently being vi ...
Inconsistent texture loading issue within material editor
UE - Rendering - Architecture - Materials - Jul 16, 2025A licensee has reached out via EPS about a texture loading issue they are having in-editor. I summarized the most important points below:The issue relates to texture load failure associated with mat ...
Native variable references like GameplayAttribute cannot be searched by "Find in Blueprints" or "Asset Search"
UE - Framework - Blueprint Editor - Jan 4, 2023"Find in Blueprints" does not turn up results when searching a GameplayAttribute by name, even when there is a GameplayEffect blueprint that has a modifier for that GameplayAttribute. This is becau ...
Sub-world partitions do not properly handle partial editor loading as world partition standalone level instances' spatially loaded actors do not get loaded even when the Level Instance is force loaded or loaded in by region.
UE - Engine Scaling - Streaming - World Partition - Aug 19, 2025Context Level Instancing is a level-based workflow designed to improve and streamline the level editing experience. In a standalone Level Behavior, when the Level Instance Actor is loaded through it ...
Changes to Instanced Properties default value on BP not propagated to placed actors in the opened level
UE - Core - Systems - May 15, 2025In UE versions 5.4 and onwards (as of CL 42589677 in Main), when an Instanced UObject property is defined in an Actor Blueprint, modifying the default value in the Blueprint does not propagate the c ...
GAS and single process PIE: modifiable static variables accessed by server and client
UE - Gameplay - Gameplay Ability System - Nov 16, 2022See: UAbilitySystemGlobals::HandlePreLoadMap GAS features static variables that are modified by both server and client, thus result in issues in single process PIE where they access the same memory ...
Null Material Layers in Material Instances cause Opacity Mask and WPO to break on Nanite Meshes
UE - Rendering - Architecture - Materials - Oct 31, 2024When a Material Instance is loaded that has a nullptr layer in StaticParametrs.Materiallayers. The Material Instance will create it's own CachedExpressionData but the ConnectedParameterMask will be ...
LevelEditor: "Replace Actor" marks level as dirty even when using external actors
UE - Engine Scaling - Streaming - Jul 15, 2024When using external actors, adding/removing/replacing/editing an actor instance inside a level does not cause any modification to the Level package, which helps reduce contention for the map file on ...
Orientation Warping breaks incoming poses where bones are in component space
UE - MVF Character - Animation - Apr 17, 2025The orientation warping node breaks incoming poses where bones are already in component space. This is because, in EvaluateSkeletalControl_AnyThread, we are repeatedly setting bone transforms direc ...