Unreal Engine Issues
Unreal Engine Issues
Disabling DFAO prevents landscape from contributing to Lumen scene
UE - Graphics Features - Lumen - Oct 10, 2023From licensee: We disabled DFAO on our project (using r.DistanceFieldAO 0) to replace it with Lumen occlusion, as the combination of both was creating dark blobs under bushes and grass. However, we ...
The hierarchy of Actors in LevelInstances can break when using BPs as parent
UE - World Creation - Worldbuilding Tools - Level Instances - Feb 18, 2026The hierarchy of a LevelInstance actors (Outliner) will break when cooking. The source is the call to AActor::RerunConstructionScripts in FWorldPartitionLevelHelper::MoveExternalActorsToLevel. The ...
[Mobile/Forward Rendering] PlanarReflection does not work when the reflection plane faces certain directions
UE - Platform - Mobile - Sep 24, 2025Note: This repros on 4.27 and all 5.x versions. When using the mobile renderer and/or forward shading, Planar Reflection will simply not work if the reflection plane normal has components that add ...
Issues changing physics properties on destructible meshes
UE - Simulation - Physics - Destruction - Oct 15, 2015Numerous issues when manipulating destructibles. 1) Changing collision response pre-fracture will not affect chunks post-fracture 2) Changing collisions response pre-fracture will prevent damage f ...
Playing sequences in reverse snaps after sequence has first ran
UE - Anim - Sequencer - Dec 29, 2016I first came across this bug when I was working with Actor Sequences and noticed that the door I had opening would snap back when I tried to close it. Later I discovered that the issue was with play ...
USkinnedMeshComponent::FindClosestBone does not respect bRequirePhysicsAsset parameter
OLD - Anim - Mar 20, 2017A licensee has reported that the USkinnedMeshComponent::FindClosestBone function does not respect the bRequiresPhysicsAsset parameter, resulting in the bone returning bones that are not part of the ...
SceneCaptureComponent2D 'Primitive Render Mode' Always Selects Legacy Option
UE - Graphics Features - Nov 9, 2017When using SceneCapture2D and trying to edit the "Primitive Render Mode" (found in Details panel, Scene Capture) you can select the "Render Scene Primitives (Legacy)" and the "Use ShowOnly List" opt ...
Quickly using alt-tab with a blueprint in a new window causes the event graph to capture input of the alt key
Tools - Nov 13, 2017Quickly using alt-tab with a blueprint in a new window causes the event graph to capture input of the alt key. This issue does not occur when the blueprint is a tab of the main UE4 editor window. Th ...
Audio/Video out of sync after seek
Media Framework - Jan 29, 2018There is an issue that sometimes occurs when using the seek option in the media player while the Decoder is set to WMF. When this happens the audio desyncs from the video and for the rest of the vid ...
Geometry Pen Tool Duplicates Bushes On Grid Size 1 & 5
UE - LD & Modeling - Modeling Tools - BSP - Mar 7, 2018There is an issue occurring when creating brushes with the pen tool at grid size 5 where verticles or the brush shape itself seems to be doubled. This issue also occurs if the grid size is 1, though ...