check(PIEInstanceID != -1) fails when executing SeamlessTravel

UE - Gameplay - Mar 2, 2017

Per https://udn.unrealengine.com/questions/349614/checkpieinstanceid-1-fails-when-executing-seamless.html ...

Animation retargeting adversely affects looping animations

OLD - Anim - Nov 21, 2014

Retargeting a skeleton to a looping animation results in the animation skipping at the end of the loop (Appears to miss 1 or 2 frames.) ...

Linux Native Toolchain depends on libninfo5 which is not bundled

UE - Platform - Linux - Sep 6, 2019

libtinfo.so.5 => /lib/x86_64-linux-gnu/libtinfo.so.5 (0x00007fc27cf4d000) bschaefer@bschaefer-Precision-T7600:bin$ ldd ./clang linux-vdso.so.1 => (0x00007ffceefe3000) libpthread.so.0 => /lib/ ...

Biquad Filter is incorrect when bandpass is 1.0

UE - Audio - Signal Processing - Aug 20, 2024

The bandwidth on the biquad loepass filter is cutting frequencies well below 20kHz when the bandwidth is 1.0. Slack convo: [Link Removed] Visualization:[Image Removed] ...

Getting the Outer (GetOuter()) inside AssetUserData::PostEditChangeOwner added to an instanced actor in a level returns the Outer marked with "Trash"

UE - Framework - Nov 20, 2024

When you call GetOuter() inside AssetUserData::PostEditChangeOwner, the Outer that is returned, is marked as "Trash". This is because the object is constructed again when an AssetUserData is added. ...

Physics Constraint Component loss of accuracy

UE - Simulation - Physics - Mar 6, 2025

Physics Constraint Component has lost accuracy between Unreal versions 5.2 and 5.4 (and up). When measuring the exact distance between rigid bodies constrained by a Physics Constraint Component, the ...

NavArea blueprints in Develops folders appear to have no affect

UE - AI - Nov 6, 2015

If the user creates two NavArea Blueprints (one in the content folder and the other in a developer folder) if one is inside of a developer folder then it will appear to have no affect when it comes ...

FString.Mid doesn't react appropriately when given negative values for the Count variable

UE - Foundation - Core - Jul 16, 2015

If you use a 5 character string (hello) to call the Mid function and provide 0 for start, -1 for count, it'll give you the entire string. This should either return an assert or treat all negatives a ...

Static meshes in a particle system are not affected by decals

UE - Graphics Features - Dec 21, 2017

There is an issue where Static meshes in a particle system are not affected by decals, It is unsure if this is intentional behavior or not. This issue does not appear to be a regression Versions ...

Material editor crash in 5.0.2

UE - Rendering Architecture - Materials - Sep 2, 2022