Unreal Engine Issues
Unreal Engine Issues
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 ...
When duplicating the last point in a closed-loop spline, its metadata is inserted at the wrong index
UE - Editor - Workflow Systems - Nov 1, 2023The SplineComponentVisualizer allows users to alt+drag on a spline point to duplicate it. When this is done on the last point of a spline marked as "closed-loop", the new point is correctly added at ...
Rendering of a Text Widget with Outline does not track LayerId correctly
UE - Editor - UI Systems - May 27, 2025Text widget with Outline uses 2 LayerId levels to draw the outline and the text glyphs. This can be seen in function FSlateElementBatcher::AddShapedTextElement(), where lambda BuildFontGeometry() is ...
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 - World Creation - Worldbuilding Tools - 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 - Anim - Gameplay - 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 ...
BP hierarchy change triggers incorrect map actor load warning: AttachTo: '{0}' is not static {1}, cannot attach '{2}' which is static to it.
UE - Gameplay - Blueprint - Apr 11, 2024When a blueprint's component hierarchy is changed by changing a child component's mobility value to Static while deleting its parent component which has Movable mobility, levels saved with an outdat ...
UnkownRef Mips can cause TextureStreaming peaks during loading
UE - Graphics Features - Mar 27, 2023UnkownRef Mips is meant to fix/workaround the problem where some textures are used for rendering but they don't have any component references them (such as texture used by PP effects) These UnkownR ...
Inconsistent behavior with Register State Branches
UE - Editor - Workflow Systems - Aug 31, 2023ISourceControlProvider::RegisterStateBranches(...) doesn't reliably warn on conflicts ISourceControlProvider::RegisterStateBranches(...), specifically FPerforceSourceControlProvider, is supposed to ...
AreaNavModifiers generated by SplineNavModifierComponent have the component-to-world transform incorrectly applied twice
UE - AI - Navigation - Aug 15, 2025USplineNavModifierComponent was made available in UE 5.4. It generates several FAreaNavModifier instances covering a region with a certain thickness around a USplineComponent, and worked correctly u ...