Networked Root Motion Sources can experience desynchronisation that is not present in animation root motion under forced adjustment

UE - Gameplay - Player Movement - Feb 13, 2024

In a networked environment with high packet loss (or high forced adjustment factor), motion applied using Root Motion Sources can desynchronise under conditions that animation root motion does not. ...

Matinee movie recording is broken in 4.10

Tools - Dec 18, 2015

When trying to record a movie from a matinee in 4.10, it can fail for a number of reasons: 1. The folder does not exist 2. The cinematic view modes do not take effect 3. Trying to record a streamin ...

Level will crash if Landscape material layer can't find LayerInfo file.

UE - LD & Modeling - Terrain - Landscape - Sep 8, 2016

Artist had problem open his level after LayerInfo file was deleted ...

BP timelines: when converting internal curve to external, the external curve isn't used until BP is recompiled

UE - Framework - Blueprint Editor - Aug 28, 2023

Blueprint timelines: when converting an internal curve to an external curve asset, the curve asset's data isn't used until the blueprint is recompiled. This is confusing as there is no indication th ...

[CrashReport] UE4Editor_VulkanRHI!VulkanRHI::VerifyVulkanResult() [vulkanutil.cpp:357]

UE - Graphics Features - Nov 10, 2017

This is a low frequency crash that has occurred since at least 4.14 User DescriptionsStarted with vulkan.. crashed immediately.Activated vulkan, and moved around. Only that.I imported a 3d model in ...

Mover | FStanceModifier adjustment teleport on Crouch/Uncrouch can fail when child components intersect world

UE - Gameplay - Player Movement - Mover - Feb 3, 2026

Context When crouching and uncrouching with Mover’s DefaultMovementSet, the pawn capsule’s half height is changed. This behavior mimics the CharacterMovementComponent. To ensure the pawn’s feet sta ...

Unreal Header Tool can sometimes fail if an Engine plugin is Enabled By Default and has the "Program" Module Type set

UE - Foundation - Core - Feb 15, 2018

An Engine plugin with the Program module type and EnabledByDefault set to true can cause the Engine to fail to build successfully due to UHT failing. I was only able to reproduce this behavior using ...

Tilemaps with masked materials respond to lighting at incorrect directions

UE - Gameplay - Paper2D - Nov 19, 2018

Tilemaps using lit methods of rendering are subject to strange lighting behavior. If the material for the tilemap is using a 'masked' method of rendering.  Lighting will appear at incorrect angles. ...

[AI] WP Dynamic navmesh fails to rebuild tiles with actors that are loaded but not part of the base navmesh.

UE - AI - Navigation - Feb 18, 2025

WP dynamic navmesh does not properly react to actors or navigation modifiers that are loaded in areas that the navmesh has not yet streamed into. Although the actors/modifiers are not part of the ba ...

Project packaged on Windows for Linux crashes after exiting on Linux

Tools - Aug 18, 2016

I noticed this after packaging multiple samples projects on Windows for Linux and running them on my Linux machine. The project exited cleanly, but there was a crash and callstack generated in the ...