Hot Reload fails if a project and Engine are placed next to each other in the same root folder that has the same name as the project

UE - Foundation - Cpp Tools - Hot Reload - Jan 8, 2019

Hot Reload does not work if a project and the Engine that project is associated with are placed next to each other in the same root folder that shares the same name as the project. During the Hot Re ...

Previous Tangent Recalc` and Size by Life misbehave at low FPS

UE - Niagara - Jun 18, 2019

At low FPS particle systems with "Previous Tangent Recalculation" enabled in the Ribbon Data result in messy mesh generation. Found in 4.21 CL# 4753647, 4.22 CL# 6574378, 4.23 CL# 6925347, and 4.24 ...

Skybox not rendering in packaged project with Vertex Fogging enabled

UE - Platform - XR - Feb 10, 2020

Vertex Fogging setting causes skybox material on large skybox mesh to not be rendered. Confirmation for 4.25 blocked by [Link Removed] ...

Actor attached to child actor fails to serialize as part of map

UE - Framework - Components - Nov 3, 2023

Attaching other actors to a child actor (actor spawned by ChildActorComponent) fails to serialize correctly as part of the map. The attached actor loads as detached and resets its position back to w ...

UV Offset Effect Material in RetainerBox Causes Visual Artifacts in Editor Preview

UE - Editor - UI Systems - UMG - Apr 22, 2025

When a UV Offset is applied in a RetainerBox effect material, visual artifacts appear only in the editor — not at runtime — if a widget with a dotted preview outline (like CanvasPanel) is placed dir ...

20 FPS performance drop between 4.7.6 and 4.8 on devices rendering Metal only

UE - Platform - Mobile - Jun 22, 2015

User reported a considerable performance drop on iOS between versions 4.7.6 and 4.8. I was able to reproduce this perf drop using the steps he provided. ...

BP child not overriding parent's mesh in Nativized builds

UE - Gameplay - Blueprint Runtime - Jan 3, 2017

The mesh on the right is a child of the one on the left, in a non-nativized cooked build it's a sphere, but in a nativized one, it's a cube. Regression: Working: UE4/Main, 4.15 CL 3233043 Broken: U ...

Rotated component made into root displays incorrectly in the blueprint editor

UE - Gameplay - Blueprint - Jan 25, 2017

Rotated component made into root displays incorrectly in the blueprint editor. Closing and reopening the BP editor corrects the displayed root component. ...

Debug values not updated for parallel eval Animation BPs

OLD - Anim - Oct 22, 2019

The watched values of a level instanced ABP do not update if a.ParallelAnimEvaluation is enabled. ...

Depth Not Rendered Correctly When Using CustomProjectionMatrix in SceneCaptureComponent2D

UE - Graphics Features - Apr 15, 2020

The depth is rendered incorrectly when using a custom projection matrix in SceneCaptureComponent2D. You can find an example project at [Link Removed]. You can find where the CustomProjectionMatrix ...