Unreal Engine Issues
Unreal Engine Issues
Crash when a StateTree-related Parameter is of a type that includes two nested arrays with the same name (due to FPropertyChangedEvent::ArrayIndicesPerObject using array names to map to their changed indices)
UE - Framework - Dec 19, 2025This issue was reported in the context of adding and setting parameters on StateTrees, Tasks and related assets, but its root cause lies in the structure FPropertyChangedEvent and can possibly affec ...
ES3.1 preview causes temporary freezing when selecting objects in the viewport on Mac
Tools - May 3, 2019The editor will freeze for seconds at a time when selecting between objects in the viewport after using ES3.1 preview on a Mac. ...
Morph target for SK_BoxMorph_1 exceeds 1.0, causes the sphere shape to bend inward
Docs - Samples - Jul 10, 2017In Content Examples, the morph targets assigned to SK_Box_Morph_1 exceed 1.0. While it's not "wrong" for morphs to go beyond that, it doesn't seem like it's a great demonstration in the asset. Goi ...
Camera Shake Oscillation Duration no longer accepts -1 as indefinite
UE - Gameplay - Jul 30, 2015The Camera Shake Class no longer allows for indefinite shaking via setting a negative value in the Oscillation duration, per the tooltip instructions. This happens when using either the Play World ...
MaterialCurve of AnimSequence is not working with LOD 1~ if assigned Material manually
OLD - Anim - Apr 3, 2015MaterialCurve of AnimSequence is not working with LOD 1~ if assigned Material manually. Assigning material to LOD0 seems sharing material info with other LODs but material info is never shared if as ...
ChaosCacheManager is not recording the Observed GeometryCollections NotifyBreak states between level loading and will default to false if changed from Record to Play
UE - Simulation - Core - Mar 28, 2025ChaosCacheManager (CCM) is not recording the Observed GeometryCollections (GC) NotifyBreak states between level loading and will default to false if changed from Record to Play. AChaosCacheManager ...
Particle AnimTrails do not render on Android with Mali chipset when using OpenGL ES 3.1
UE - Platform - Mobile - Nov 22, 2016Particle AnimTrails are not rendering on Mali but will render on the Adreno when using the OpenGL ES 3.1. ES2 renders correctly on both devices, just ES 3.1 does not. The devices compared: Working ...
Hair Shadows Not Affecting SSS Back Scattering (Subsurface Profile)
UE - Rendering - Graphics Features - Mar 30, 2026Groom strands do not appear to correctly block transmitted light for Subsurface Scattering Profile Materials. In some cases, not only will they not block the light, but can instead lead to more ligh ...
Setting Physics Blend Weight to anything between 0 and 1 causes erratic behavior
UE - Simulation - Physics - Jul 27, 2015If the user simulates all bodies, and then sets the physics blend weight to a decimal value between 0 and 1, the skeletal meshes will spin out of control. This doesn't happen if the physics blend w ...
FBX sdk give wrong normals when compile with Visual Studio 17.4.1
UE - Editor - Content Pipeline - Import and Export - Nov 24, 2022At the time this Jira is created, UE 5.1 and 5.2 is using VS 17.3.6 which is working correctly. any update after should repro the issue. ...