Nanite UV switch seams

UE - Graphics Features - Jun 13, 2025

Analytical Derivatives are not calculated properly when using UMaterialExpressionSwitch. Disjoint UVs in screen space result in large jumps in the derivatives, which can cause artifacts as the wrong ...

Engine crashes while attempting to resimulate procedural foliage volume with target layer set on landscape proxies

UE - World Creation - Worldbuilding Tools - Foliage - Apr 17, 2015

If a procedural foliage volume attempts to use the "target layer" feature and resimulate while encompassing a landscape proxy, the editor will crash. Frequency: 3/3 Crash Report: [Link Removed] ...

Adding a Material Parameter track sets Parameter to Master Material defaults

UE - Anim - Sequencer - Aug 5, 2016

In Sequencer, adding a Material Parameter track sets Parameter to Master Material defaults ...

Character animations are not played in sequence created from Recording First Person Template

UE - Anim - Sequencer - Aug 5, 2016

Character animations are not played in sequence created from Recording First Person Template Follow-up to [Link Removed] ...

Function calls inside destructor are not called when expected.

UE - Gameplay - Blueprint - Jul 13, 2015

Functions called in the destructor are not being called properly. Setting a call to AddOnScreenDebugMessage is displayed at the start of PIE rather than when the actor's destroy is called. ...

Android Client unable to join VOIP Host Session

UE - Online - Aug 6, 2019

Android client is unable to join a VOIP Hosted Session. The following messaging occurs when the Client tries to join a found session on Android:LogInit: BSD_Android: I am localhost (127.0.0.1:0) L ...

Crash on Mac on exit.

Media Framework - Aug 17, 2020

A licensee reported trouble with a crash on exit on Mac. They discovered that the file AvfMediaPlayer.cpp, on the function Open there is this piece of code:// Force the AV player to not be able to ...

Waking both of a constraint's rigidbodies re-enables collisions between constrained actors that were disabled by a Physics Constraint Actor

UE - Simulation - Physics - Solver - Apr 12, 2022

Waking both of a constraint's rigidbodies re-enables collisions that were disabled by the physics constraint You can also get this issue to occur by either shooting the two cubes around a bit, or by ...

Movement corrections occurring while standing still on rotating platforms

UE - Gameplay - Player Movement - Oct 5, 2022

When the player is controlling a Character actor, using the CharacterMovementComponent (CMC), unexpected movement corrections will occur while standing still on a movement base that is rotating. ...

Some Niagara FX does not show up in MovieSceneCapture when AgeUpdateMode is DesiredAgeNoSeek

UE - Niagara - Cinematics - Sep 17, 2024

CL23957356 changes how to calculate FrameOffset in FNiagaraSystemUpdateDesiredAgeExecutionToken::Execute(). After this change, DesiredAge + FrameOffset could be 0.0 for some a couple of initial fram ...