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 ...

Crash When Raycasting Against Mesh With Multiple Materials

UE - Simulation - Physics - Feb 26, 2016

When using a raycast trace against a blueprint that has a child component with multiple materials will cause the editor to crash after a few times. This will not be an instant crash, but requires th ...

BP - Editing defaults on a nested subobject of a component inherited from a native parent class won't preserve those defaults when the BP is instanced.

UE - Gameplay - Components - Jan 19, 2017

I think the issue is that in GetInstancedSubobject() (CoreNative.cpp), the following bit of code is not considering that the instanced subobject might be outered to another instanced subobject withi ...

Modifying ShooterGame header file for faster compiling causes crash behavior.

UE - Foundation - Core - Jan 11, 2019

Using bFasterWithoutUnity and MinFilesUsingPrecompiledHeaderOverride, on ShooterGame.Build.Cs results in Engine crash. ...

Nanite shadow issue in commandline rendering

UE - Graphics Features - Nov 28, 2023

YCoCg to sRGB?

UE - Niagara - Rendering - Mar 20, 2024

Both the material and the Niagara compute shader use the same function to interpret the YCoCg color data, but the Niagara compute shader returns an incorrect color. Also found on CL: 32347737 in Re ...

Editor crashes when using PCG SpawnActor with a DataLayer inside a Level Instance

UE - World Creation - Procedural Tools - Jun 4, 2025

A PCG actor is assigned to a DataLayer and placed inside a Level Instance. Then that Level Instance is placed into a World Partition map. When the SpawnActor node in the PCG graph is set to MergePCG ...

AI Pawn Sensing component cannot see and hear at the same time

UE - AI - Mar 12, 2015

Hear events are never fired while See events are fired. They are mutually exclusive, with See events taking priority if both happen. ...

Using "Play Animation" node, if current animation has a looping timed particle it will continue playing

OLD - Anim - Jun 24, 2016

Calling "Play Animation", if current animation has a looping timed particle it will continue playing ...

Cursor Overlap events don't work on characters

UE - Gameplay - Sep 4, 2015

Setting up mouse over events for a character do not trigger. ...