Adjusting Default Light Settings for Atmospheric Fog causes Crash

UE - Graphics Features - May 2, 2016

Adjusting default light settings in the Color Picker palette for atmospheric fog causes the engine to crash in UE 4.12 Preview Regression: This does not occur in UE4.11 ...

[CrashReport] D3D 'Hung' crash - FD3D11DynamicRHI::ReadSurfaceDataNoMSAARaw

UE - Graphics Features - Jan 4, 2017

This is a frequent D3D Hung crash, similar to [Link Removed] and [Link Removed]. A potential fix for the other crashes was released in 4.14.2, but this crash is still occurring on that release. ...

UMG element clipping does not work on Galaxy S8 (Mali)

UE - Platform - Mobile - Mar 13, 2018

UMG clipping requires stencil. Seems like we don't request stencil when creating backbuffer Changing const int EGLMinStencilBits = 0; to const int EGLMinStencilBits = 8; fixes this. ...

RF_WasLoaded is set to False in PIE for instances of a Blueprint if the Blueprint is recompiled

UE - Gameplay - Blueprint - Apr 5, 2019

The RF_WasLoaded flag is set to false for Blueprint instances in PIE if the Blueprint is edited and compiled. This is fixed by saving the level which is a simple workaround but this should be needed ...

Cannot change Collision Profile of BP component instances

UE - Simulation - Physics - Oct 24, 2019

BP instances placed in level cannot have their components' collision profiles modified to anything other than default and custom. Note that this did not occur in 4.22 (after applying the separate ...

Niagara system loses source emitters when moving Engine from 4.22 or earlier to 4.23 or later.

UE - Niagara - Nov 29, 2019

The following code causes this behavior.// NiagaraSystem.cpp for (FNiagaraEmitterHandle& EmitterHandle : EmitterHandles) { EmitterHandle.ConditionalPostLoad(NiagaraVer); if (!EmitterHandl ...

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 ...

Moving a 3D widget that has been placed in the scene will cause a crash

UE - Editor - UI Systems - Jan 18, 2016

If a user places a 3d widget in to the level it will cause a crash when moved with the movement arrows. ...