Deprecating a non-const blueprint interface function replaces the implementation of the event with an empty custom event

UE - Gameplay - Blueprint - Oct 19, 2023

This behaviour is only observed when implementing the function as a custom event from a blueprint interface. This behaviour is not observed in actors where the blueprint interface function is implem ...

Gameplay Tags set as Default in Local Variables do not show as references in Reference Viewer

UE - Framework - Blueprint Editor - Oct 30, 2023

Normal variables with gameplay tag defaults will show up in the reference viewer.Other reference types used as a local variable default value will show up in the reference viewer correctly. ...

Single sided complex collision mesh collision blocks character movement from backside

UE - Simulation - Physics - Query - Nov 17, 2023

Commenting out the branch in FTriangleMeshSweepVisitor::VisitSweep is a work-around.if (CullsBackFaceSweepsCode != 0) { if (VectorMaskBits(IsBackFace)) { // Don't cull the back face ...

Keep Simulation Changes does not work for Actors that have replaced root component

UE - Framework - Components - Jan 31, 2024

RelativeLocation and RelativeRotation in the root component are collected in UActorComponent::AllUCSModifiedProperties, so copying simulation result is skipped in EditorUtilities::CopyActorPropertie ...

Niagara using a Volume and Mesh renderer with a shared base material does not renderer correctly

UE - Niagara - Mar 26, 2024

Using a shared base material with both a Volume and Mesh renderer causes the emitter to render as a glowing box at the scale of the bounding box. ...

Sampler Source: From Texture Asset with Streamed Virtual Texture

UE - Rendering Architecture - Mar 28, 2024

It appears that Texture Samplers for Virtual Textures do not respect the Tiling Method from the Virtual Texture Asset when the "Sampler Source" is set to "from texture asset". ...

Frustum culling provides inconsistent results causing particles to render even when the bounds are out of view.

UE - Niagara - Rendering - Nov 5, 2024

When the camera is just outside of the box bounds and it is angled directly away from it , it will start rendering the particles again (as determined by stat GPU differences) despite being out of vi ...

Data loss with subobjects in Blueprint arrays

UE - Framework - Blueprint - Mar 6, 2025

If a file has been opened in the editor, it cannot then be unshelved by perforce until the editor is restarted

UE - Editor - Workflow Systems - Jul 8, 2022

When the Editor launches it does not have a file lock on assets that are not open. When the asset is opened for editing, UE gets a lock on the file and this lock persists even after the tab is close ...

IsLocalController returning incorrect value when PIE listen server travels back to standalone map

UE - Networking - Jun 11, 2025

In this situation where the listen server travels back to a level without listening, IsLocalController can return the incorrect value. After the NetDriver has been shutdown and destroyed, the pawn a ...