FileSystemDerivedDataBackend may output a corrupted access log

UE - Foundation - Core - Derived Data - May 20, 2021

This problem is caused by the AccessLogWriter has not been flushed at the termination. The following workaround flushes the Writer.class FFileSystemDerivedDataBackend : public FDerivedDataBackendInt ...

Crash after importing a 16k Normal Map while Unreal Real is Preparing Texture

UE - Texture - Sep 12, 2022

This is a regression tested in //UE4/Release-4.27 cl18319896 Editor crashes after importing a 16k Normal Map while Unreal Real is Preparing Texture. Other non-normal maps seem to work without issue ...

Data Layers: GetDataLayerInstanceFromAssetName differs between editor and non-editor

UE - World Creation - Worldbuilding Tools - Data Layers - Apr 9, 2024

From licensee: The function AWorldDataLayers::GetDataLayerInstanceFromAssetName() uses different names in #WITH_EDITOR and without editor builds: #WITH_EDITOR config calls DataLayerInstance->GetDa ...

Linux crashes in the Project Browser without using the -nocef command

UE - Platform - Linux - Feb 22, 2022

When opening Unreal Editor on Linux, the Project Browser opens but is completely unresponsive. Shortly afterwards the editor will crash. If you use the -nocef command when opening the Editor, everyt ...

[CrashReport] UE4Editor-D3D12RHI!FD3D12Viewport::PresentChecked(int) [D3D12Viewport.cpp:492]

UE - Rendering Architecture - RHI - Mar 29, 2019

Callstack is garbage past D3D12 calls but logging for visibility. Generated from CrashReporter ...

Bug in CurveLinearColor makes colors of Diffraction material white outside curve range, causing rendering artifacts

UE - Texture - May 14, 2025

There seems to be a regression with linear textures (commonly for multi-channel masked textures) in UE5.4. Setting the "Encoding Override" (under Texture > Advanced > Source Color Settings) to "Line ...

UMG Designer preview: Incorrect resolution on Samsung s8 and s9

UE - Editor - UI Systems - Jul 30, 2018

"By default, the device profile for android_high (which is used by phones such as the galaxy s8 and s9) gives a scale factor of 1.0 resulting in 1280x720. When choosing a ~2:1 device such as the gal ...

When using Lighting Scenario, loading order will affect how it's applied to the instances

UE - World Creation - Worldbuilding Tools - Foliage - Mar 7, 2019

When using Lighting Scenario, loading order will affect how it's applied to the instances, resulting in corruption if content is loaded after the lighting scenario ...

Orthographic Rendering - Lumen Reflection Artefacts

UE - Rendering Architecture - Apr 28, 2023