Popping Ribbon UVs

UE - Niagara - Mar 10, 2025

Please see the Additional Link for related UDN information. The UV popping described can be subtle, depending on settings; it's affected by spawn rate and GPU vs CPU. The popping shown in the gif t ...

Editor primitives render incorrectly in stereoscopic with instanced stereo

UE - Platform - XR - Aug 17, 2016

Trigger box icons move around when oculus head movement is used. Found in //UE4/Release-Staging-4.13 @ 3090357 QA-Promotion map Edit: 08-22: This affects volumes as well as their editor icons, upd ...

Using Blend Physics Weight causes skeletal mesh to spin at high speed

OLD - Anim - Mar 5, 2015

When Phyics Blend in the PHAT editor is set between 0 and 1, the user character will spin wildly. User has image of this affecting character in game whereas I was only able to replicate it in the PH ...

Using FEditorModeID for the "Mode" console command does not switch the modes tab

Tools - May 10, 2016

Using the FEditorModeID for the different editor modes does not affect actual modes available in editor Modes tab. Example: Command "Mode EM_Foliage" does not switch to the foliage mode Workaround ...

Child Actor component is duplicated in Standalone Game

UE - Gameplay - Jan 12, 2017

Child Actor component is duplicated in Standalone Game. No other play modes or packaged game are affected. The additional actor will disappear after 1 minute. *This is a regression: Doesn't occur ...

Set All Bodies Below Simulate Physics Only Causes Ragdoll Effect if it is Set to Root Bone

UE - Simulation - Physics - Sep 29, 2017

-This functions in 4.16 -Physics will only simulate if the Third Person Character bone name variable is set to root -Physics does not affect any other bone -Make sure to plug in set in collision f ...

Performing a Clean on a project using a binary Engine installation on Mac removes some Engine .dylib files

UE - Foundation - Core - May 17, 2018

When a Clean is performed on a code project that uses a binary Engine installation on a Mac, some of the Engine's .dylib files are removed during the Clean process. A Clean process for a project usi ...

Static Mesh LOD Generation Produces Bad Shading and Holes in Mesh

UE - Graphics Features - Feb 19, 2019

Auto generated LODs create a mesh with holes and geometry that creates incorrect shading. Working as expected in 4.21 CL# 4753647 Found in 4.22 Preview 2 CL# 5035897 and 4.23 CL# 5064136 This is ...

Crash When Adding a Second Vector Parameter to Material Parameter Collection

UE - Graphics Features - Feb 21, 2019

The Editor will crash if you add more than one vector parameter to a Material Parameter Collection.  This works as expected in 4.21 CL# 4753647 Found in 4.22 Preview 2 CL# 5035897 and 4.23 CL# 506 ...

Disabling DBuffer Decals causes Decals not to render

UE - Graphics Features - Mar 8, 2019

Disabling the Decal DBuffer in the  Project Settings>Rendering causes the Decals to not render on geometry that overlap their respective Decal Actor. Tested in 4.21.2 (CL - 4753647), 4.22 (CL - 5 ...