Unreal Engine Issues
Unreal Engine Issues
r.Lumen.Reflections.DownsampleFactor split screen artifact
UE - Graphics Features - Lumen - Dec 6, 2024In Split-Screen, with "r.Lumen.Reflections.DownsampleFactor" set to 2, it is possible to have vertical colored artifacts on View 1 (the second view). The Licensee reported the artifact occurred on ...
Line Attractor Strength Varies By Frame Rate
UE - Niagara - Aug 20, 2015The Line Attractor node seems to render differently (have different strengths) between Cascade Viewport, Editor Level Viewport, PIE and Standalone/Launched Game In trying to capture movies for this ...
Light Leak Issue in Modular Buildings (Lumen HZBTraversal)
UE - Graphics Features - Lumen - Oct 14, 2025Starting in Unreal Engine 5.6, disabling "r.Lumen.ScreenProbeGather.ScreenTraces.HZBTraversal" can lead to light leaking between adjacent or overlapping meshes. Also tested on Release-5.6, CL: 4523 ...
The drawing order of widgets becomes wrong when GlobalInvalidation is enabled,
UE - Editor - UI Systems - Slate - Nov 26, 2021When trying to create a widget with specific steps, the drawing order may not be correct. This is not reproduced when Global Invalidation is disabled, and the state can be restored. This issue is pr ...
ShowOnlyInnerProperties does not work on a struct property in a class nested within another class as an instance
UE - Gameplay - Blueprint - Feb 19, 2019When the ShowOnlyInnerProperties property specifier is used for a struct property, the properties contained within the struct are exposed to the Blueprints Details panel as if they were part of the ...
Data Layers: GetDataLayerInstanceFromAssetName differs between editor and non-editor
UE - World Creation - Worldbuilding Tools - Data Layers - Apr 9, 2024From licensee: The function AWorldDataLayers::GetDataLayerInstanceFromAssetName() uses different names in #WITH_EDITOR and without editor builds: #WITH_EDITOR config calls DataLayerInstance->GetDa ...
Duplicating many Actors at once in a Level Instance while in Level Instance Edit will result in a jumbled mess of Actors on the Persistent Level
UE - World Creation - Worldbuilding Tools - Level Instances - Feb 12, 2025Duplicating many Actors at once in a Level Instance while in Level Instance Edit will result in a jumbled mess of Actors on the Persistent Level. The licensee has encountered this in Unreal 5.4 and ...
ACineCameraAttachMount's "Target Actor" constraint does not work with Spawnables or Replaceables in Sequencer
UE - Virtual Production - Tools - Virtual Camera - Aug 12, 2025Constraints (UTickableConstraint) are usually created throuh the "Animation" tab available in the Editor's "Animation Mode". When created through that interface while Sequencer is open, the internal ...
Modifying FinstancedStruct (Blueprint structs) properties inside another FInstancedStruct triggers an ensure and properties do not get saved.
UE - AI - Dec 16, 2024There is a bug with Blueprint structs having FInstancedStruct as a property. If you modify the DefaultValues of any property of an FInstancedStruct inside the blueprint struct asset, an ensure will ...
Niagara - "Make Static" nodes do not seem to be working correctly.
UE - Niagara - Apr 7, 2025When a "Make Static" node is used in a Niagara Function Script or Niagara Module Script to supply the input value for a Static Switch Selector or, a Function Parameter, or a Function Parameter Defau ...