Blueprint compile fails after changing the default values of a struct that is part of another struct that makes up a Data Table that is used within the Blueprint.

UE - Gameplay - Blueprint - Dec 23, 2016

Changing the default value of a struct that is included as an array in another struct can prevent any Blueprints that use a DataTable made from the second struct from compiling. It appears to be a p ...

Orientation is wrong for client in networked HMD game when UseControllerRotationRoll is true

UE - Platform - XR - Feb 20, 2017

A networked VR (HMD) game will result in an undesirable rotation for the pawn on startup for a network client, and the issue is dependent on timing. ...

Crash when adding SK_Mannequin to a Level Sequence in QAGame

OLD - Anim - Feb 20, 2017

This crash only occurs when the asset is dragged and dropped into the level. Workaround Add the asset to the level, then to the sequence. NOTE This does not occur in //UE4/Main ...

FRayTracingGeometryManager::Tick() called twice during a single frame

UE - Graphics Features - Ray Tracing - Mar 5, 2025

UDN licensee Prophecy Games has encountered an issue in which the RaytracingGeometry::Tick() function is called twice during a single frame. This causes an assert to trigger, which blocks them from ...

Crash playing in viewport with a character that has a Wheel Class

UE - Simulation - Physics - Aug 27, 2016

Crash occurs when playing in editor with a character that has a Simple Wheeled Vehicle Movement Component, with a Wheel Class assigned to it. This crash seems to only occur if Don't Create Shape is ...

Deleting a Sync Marker created by an Animation modifier deletes all Sync Marks made by the Animation Modifier

UE - Anim - Jan 14, 2022

Using the delete key or context menu to delete a single sync marker created by an Animation Modifier deletes all sync markers created by the Animation Modifier. If all the markers are deleted, and ...

Code delegates duplicate function calls when owning actor is duplicated in the editor

UE - Foundation - Core - Jan 15, 2016

If an actor that contains a delegate bound in code is duplicated after being placed in the level, the delegate for the duplicate will also trigger the delegate for the original as well. ...

When an active Niagara Component is moved and reset+reactivated in the same frame, "Interpolated Spawning" causes "Spawn Burst Instantaneous" to spawn particles in the previous frame's outdated location

UE - Niagara - Mar 6, 2024

Consider a Niagara System with an Emitter in "Global Space" that has "Interpolated Spawning" active and a "Spawn Burst Instantaneous" module with a "Spawn Time" of 0.0 (for example, the built-in Con ...

RootMotion Malfunctioning When Played in Lower Framerates

UE - Gameplay - Player Movement - May 2, 2016

Root Motion Animations are not functioning correctly during lower frame rates. For example, a character moving forward 2 meters at regular frame rate will move 10 meters at a lower frame rate. Regr ...