Unwanted black boundaries are displayed in a vertical split-screen with 3 players.

UE - Gameplay - Dec 2, 2019

Floating point error from UGameViewportClient::SplitscreenInfo causes this issue. FMath::TruncToInt( 3240 /*ViewportSize*/ * 0.333f/*Ratio in SplitScreenInfo*/ ) = 1079 I suggested a following t ...

Unable to add/compile code for Automation Test

UE - Automation Test - May 22, 2017

When following the documentation on setting up automation tests, the sample provided for "Simple Tests" does not successfully compile. One of two compiles errors is given based on the TFlag used A ...

HTML5 fails to compile on Mac/Windows - Shipping

UE - Platform - Apple - Jan 13, 2017

HTML5 fails to compile on Mac when built for shipping in binary I did not see this when packaging for development yesterday Does not occur in 4.14.3 The error appears to be WebGL relatedError: Web ...

iOS movie (mp4) has no sound in the playback.

UE - Platform - Mobile - May 16, 2017

There is no sound in the movie play in iOS, built with 4.16 GitHub source code version. you can simply reproduce using attached sample project. This is reproduced in iPhone 5s(10.3.1) iPhone 6(iOS ...

Unable to edit double variable in property matrix

UE - Editor - Workflow Systems - Oct 2, 2023

Since UE5.0, cannot edit double variables in property matrix. In UE4.27, it worked correctly and could be edited from the property matrix. This is because double variables are not supported in SProp ...

Animated characters may appear in A pose after loading a file with Path Tracer enabled

TM - Rendering - Mar 12, 2025

When saving a file with Path Tracer enabled at the time of save, animated characters will appear in an A pose state. This will persist until Path Tracer is disabled. Occurs in Twinmotion 2024.1.2 a ...

[CrashReport] UE4Editor_CoreUObject!UObjectBase::IsValidLowLevelFast() [uobjectbase.cpp:294]

UE - Foundation - Core - Aug 22, 2017

This is a common crash in the 4.16 and 4.17 releases. User DescriptionsWriting a custom component in C++. Hotcompiled it through VS2017. Had the BP editor open with a class derived from that compo ...

Meta Allowed Class Doesn't Allow All The Included Classes

Tools - Dec 24, 2019

The Meta Allowed Classes specifier doesn't allow the user to assign anything of the second type. Found in 4.24.1 CL#10757647 Reproduced in 4.23.1 CL#9631420, 4.25 Main CL#10868506 ...

Plugins are not creating shipping versions on package on Mac 4.23 Preview

UE - Foundation - Cpp Tools - Jul 15, 2019

When you try to package a plugin on Mac in 4.23.0 Preview 1 there is no Shipping folder generated. This was verified to not happen in 4.22.3 (via Epic Launcher). Found in 4.23.0 Preview 1 CL# 72363 ...

Traveling away from, then back to the original map in multi-process PIE with the editor as a client causes an assert

UE - Networking - Mar 28, 2016

An assert is triggered in this case because in multi-process PIE, if the editor is a client, the PIEInstance of the world context remains at -1 (see UEditorEngine::PlayInEditor). If this client inst ...