Renaming a level by WorldPartitionRenameDuplicateBuilder fails if the level contains GroupActor with non-spatial actors

UE - World Creation - Worldbuilding Tools - World Partition - Oct 24, 2023

Referece to the source level should be fixed by FReplaceObjectRefsArchive, but it is not working because ArIsModifyingWeakAndStrongReferences is not set. It can be fixed by setting the flag.class FR ...

A Client cannot join a Server after setting a GameMode in the OpenLevel node's Options string

UE - Networking - Nov 23, 2015

A Client cannot join a Server after setting a GameMode in the OpenLevel node's Options string. Reproduced in 4.9.2 binary, 4.10.0 binary, and Main (CL# 2776829) ...

Typos in Array.h

UE - Foundation - Core - Dec 28, 2015

In Array.h, there are a few typos in comments. In 4.9.2 and 4.10, the typos occur at line 2335 and 2359. *@param InIntem Item to be added. In Main, the typos are located at lines 2471 and 2495. ...

Reimporting a static mesh will cause some values to be reset back to defaults

Tools - Jul 5, 2017

Reimporting a static mesh will cause some Static Mesh Editor values to be reset back to defaults. This was reported as JIRA UE-22205 back in 4.10 and was marked fix in 4.12. However, I wasn't able ...

Renaming native struct with redirect can break user defined structs

UE - Gameplay - Blueprint - Jul 18, 2018

From https://udn.unrealengine.com/questions/444690/redirecting-ustruct-used-as-member-of-userdefineds.html In 4.20 it was changed so soft object ptrs pointing to classes work correclty with +ClassR ...

Selecting multiple actors with differing DataTableHandles causes data loss

UE - Gameplay - Jan 4, 2021

The data table customization (and probably others) tries to aggressively clear out row references that are not valid in the table they point to. This breaks when selecting multiple actors or objects ...

Pressed event triggered after calling FlushPressedKeys while holding the button

UE - Gameplay - Input - Oct 2, 2024

This is an issue related to the behavior of the FlushPressedKeys function when called manually while a button is held. Once the function is called in C++, a Pressed event gets triggered even though ...

In -game in Editor, if streaming-in a LevelInstance and initialize its world partition, then leaving that cell and make it go outside the streaming grid, to re-enter it again, will trigger a check(!StreamingPolicy) if no GC has happened during that time.

UE - World Creation - Worldbuilding Tools - World Partition - Jan 27, 2025

This crash can be fixed by adding a couple of || IsRunningGame() like it is done here:    FGenerateStreamingContext Context = FGenerateStreamingContext()        .SetLevelPackagesToGenerate((bIsPIE ...

MediaFramework movies not playing properly in Shipping

Media Framework - Nov 7, 2017

`check(Samples.Pop());` this kind of `Pop()` inside of a `check()` is in a few places in MediaSampleQueue.h and MediaSamples.cpp but `check()` expands to nothing in Shipping/Test, so, required work ...

Dithered LOD Transition does not work on some mobile devices

UE - Platform - Mobile - Aug 27, 2019

I tested with some mobile devices and Dithered LOD Transition did not work on Huawei P20 Pro. This problem does not occur with Snapdragon. This problem does not occur with Snapdragon like Pixel 3. ...