Destructible Event OnComponentFracture fires multiple times when Debris flag is enabled.

UE - Simulation - Physics - Destruction - Jul 15, 2015

When using a Destructible that is using the Event OnComponentFracture and the flags for Debris timeout/max separation and Debris Enabled will cause the event to fire for each chunk removed from the ...

Chaos Vehicles - Wheel physics bounds staying in spawn location on server

UE - Runtime - Simulation - Jun 9, 2023

Vehicle wheel shapes on the server appear to detach from the vehicle and remain at their spawn point when running a networked game. The clients physics representation is ok and as expected, i.e. whe ...

Level will crash if Landscape material layer can't find LayerInfo file.

UE - LD & Modeling - Terrain - Landscape - Sep 8, 2016

Artist had problem open his level after LayerInfo file was deleted ...

Niagara mesh particles have incorrect normals when scaled

UE - Niagara - Apr 27, 2020

Niagara mesh particle normals do not match those of static mesh actors. ...

Transition ratio getter function not correct for interrupted transitions.

OLD - Anim - Apr 7, 2016

The transition ratio getter simply uses ElapsedTime/Crossfade for the alpha on the transition. Normally this is sufficient, although if you blend between two states A and B such that you interrupt ...

Ensure clicking on the floor mesh in Anim Blueprint preview

OLD - Anim - Jan 18, 2017

REGRESSION No, occurs in 4.14.3 Ensure occurs if the user clicks on the floor mesh in the Animation Blueprint viewport. ...

Material attribute layers issue with texture sample and VT lookups

UE - Rendering - Architecture - Materials - Nov 14, 2024

When using material attribute layers in a material layer setup, there is a potential discrepancy in the number of VT Lookups presented in the material instance's Platform Stats. When the same textur ...

Blackboard decorator node does not abort lower-priority nodes

UE - AI - Feb 16, 2026

When a branch of a selector is deactivated, all auxiliary nodes and observer delegates are removed. If the branch is reactivated soon and the CurrentActiveNode remains unchanged, the behavior tree l ...

Unreal Header Tool can sometimes fail if an Engine plugin is Enabled By Default and has the "Program" Module Type set

UE - Foundation - Core - Feb 15, 2018

An Engine plugin with the Program module type and EnabledByDefault set to true can cause the Engine to fail to build successfully due to UHT failing. I was only able to reproduce this behavior using ...