The AABBTree spatial acceleration structure goes off-sync when physics substepping is enabled in a "low" framerate environment.

UE - Simulation - Physics - Mar 15, 2024

When you enable the physics substepping, if you run the console command p.Chaos.Solver.DebugDrawSpatialAccelerationStructure 1, you can see how does not follow the physical object. The user that rep ...

Clear Coat looks incorrect in the Preview when Energy Conservation on Material is enabled for non Substrate rendering

UE - Rendering Architecture - Materials - Apr 11, 2024

Enabling Energy Conservation on Material makes Clear Coat Material look weird in Preview. It looks fine in the Level Editor, but not in any "Preview" type viewport (Material Editor, Asset Thumbnails ...

Client movement and animation are heavy jittered on listen server

UE - Gameplay - Player Movement - May 10, 2019

The listen server will see jitter in clients character movement and animations. This is hard to notice without the "slomo" command but is extremely obvious using "slomo". Clients will see server and ...

Foliage lightmaps for LODs does not look correct

UE - World Creation - Worldbuilding Tools - Foliage - Jun 21, 2016

When using the foliage tool with any mesh that has a LOD the lightmap generates artifacts for the instance. The base LOD will have correct looking lightmaps, however when pulling back and seeing the ...

Stationary light shadow are occluded for additional players in split-screen mode

UE - Graphics Features - Jun 17, 2015

When using split screen multiplayer the second or more players that are added for split screen will have their characters shadows occluded when the bounds are not within view of player 1. Setting ...

Landscape renders default material if apply another material instance under ES31 preview

UE - LD & Modeling - Terrain - Landscape - Aug 27, 2019

In ES3.1 preview, Landscape will render default material if change landscape material by using material instance of landscape's material. Will render correct if using another material's instance ...

Engine Crashing with AMD R9 2 and 3 Series Cards

UE - Graphics Features - Sep 23, 2015

Multiple users are reporting crashes in the Engine when using an AMD R9 380 and 390 series cards. There was a request to have these cards added to compat lab for testing, but have not heard any upd ...

Editor crashes when assigning Landscape layer info while Forward Shading is enabled

UE - LD & Modeling - Terrain - Landscape - Nov 7, 2017

Crash occurs when Forward Shading is enabled in Forward Rendering Options User noted that if "Support Stationary Skylight" in Project Settings > Rendering > Shader Permutation Reduction is disabled ...

5.3 crashes when loading a map with an actor that had the class of one of its components changed

UE - Gameplay - Components - Feb 1, 2024

Create a blueprint based on actor, give it a SceneComponent named ExampleComp (BP_TestActor) - this should be the blueprints only componentCreate a new level (TestMap), place an instance of the bluepr ...

SetActorLabel resets components when run outside main editor process

Tools - Mar 30, 2015

Calling SetActorLabel causes an actor's components to return to default states when called from a client accessing a listen server outside of main editor process. Note: User posted code linked to ...