Niagara Particles in Mesh Shape Don't Render in Scene or Editor Preview

UE - Niagara - Dec 19, 2019

Niagara particles aren't rendered in the Niagara Editor Preview or the scene when an emitter is in it. Found in 4.24.1 CL#10756747 Reproduced in 4.25 Main CL#10808197 ...

Setting an overlay's alpha to 0 does not display as fully transparent

Tools - Feb 19, 2020

Safe zone overlay ignores alpha when set to 0.0 in DefaultEngine.ini. Tested:  4.23.1 CL#9631420 , 4.25 CL#11341939 ...

M_Volumetric_Sky_Prototype Material has compile errors

UE - Content - Engine - Mar 17, 2020

The material "M_Volumetric_Sky_Prototype" has numerous compile errors that prevent it from being used. This was reported and tested in 4.25 Preview 2 (CL-12055273) and reproduced in 4.26 (CL-121923 ...

Duplicating BP actors reset edited Variables to Default Value if Variables name start with Chinese Character

UE - Foundation - Core - Jul 29, 2020

Hints: It has no problem in 4.24, only happening in 4.25 It has no problem as long as the Variable name is contained with Alphabat(English characters) fully; or start with Alphabat(A_变量 is fine) ...

Problems in skeletal mesh merge

UE - Editor - Content Pipeline - Asset Build - May 10, 2021

There are a few issues a licensee has found with the skeletal mesh merge operation. See the UDN for more details and the proposed fixes. Note, the issue with the cloth merge is already logged in a ...

bIgnoreAllPressedKeysUntilRelease only applies to keys in the previous mapping

UE - Gameplay - Input - Jun 16, 2022

This is because the RebuildControlMappings function only checks this flag when you have a mapping that was already added, we should apply this for any new mappings as well.  I'll update the repro s ...

Disabling bLerpUVs in Nanite Settings of Static Mesh causes texture warping in clusters

UE - Graphics Features - Nanite - Jan 21, 2025

The licensee has identified a potential fix by changing if( Settings.bLerpUVs ) to if( Settings.bLerpUVs || UVIndex == 0 ) On line 389 of NaniteBuilder\Private\Cluster.cpp in UE 5.5 ...

Crash copying Geometry Cache Track in Sequencer

UE - Anim - Sequencer - Aug 6, 2020

Geometry cache section  will crash in PostLoad when track is copied. See UDN for alternative repro steps and more info on attached repro project. ...

Geometry Material Alignment not functioning in 4.8

Tools - Jun 15, 2015

Material Alignment on BSPs are not functioning in 4.8.0 Release. This is a regression from 4.7.6. The issue does appear to be fixed and functional in 4.9 (Promotable-CL-2581018) ...

GameMode::StartNewPlayer calls RestartPlayer() without checking PlayerCanRestart()

UE - Gameplay - Nov 11, 2015

Bug report from UDN thread. https://udn.unrealengine.com/questions/266937/gamemodestartnewplayer-calls-restartplayer-without.html#answer-268579 His point seems sound, we should fix it. ...