Unreal Engine Issues
Unreal Engine Issues
Variant manager crash in UPropertyValue::HasValidResolve
UE - Editor - Content Pipeline - Variants - Nov 21, 2024in the past we have reported a lot of VM related bugs which got fixed over time. Unfortunately, I think we have another one. Right now we're using 5.0.3 binaries from the launcher. Now the pro ...
Nanite: unused VertexInterpolator node disables Opacity Mask (material renders opaque)
UE - Rendering - Architecture - Jun 8, 2026On Nanite meshes, placing a VertexInterpolator node in a material graph without using it (unconnected, or routed through a disabled static switch) silently breaks the Opacity Mask and the material r ...
ApplicationReceivedScreenOrientationChangedNotificationDelegate does NOT work properly on Android
UE - Platform - Mobile - Aug 5, 2019ApplicationReceivedScreenOrientationChangedNotificationDelegate supports iOS but not Android. Probably, Java_com_epicgames_ue4_GameActivity_nativeOnConfigurationChanged should be useful for fix thi ...
ensure(false) being fired in FGenericParticlePairMidPhase::FindOrCreateConstraint from key collision
UE - Simulation - Core - Jan 27, 2025ensure(false) being fired in FGenericParticlePairMidPhase::FindOrCreateConstraint from key collision. The licensee reports one of their users reported this issue and they were able to reproduce a fe ...
[CrashReport] Crash on Mac related to cooking for IOS
UE - Graphics Features - Jul 20, 2017This is a common commandlet crash for Mac users in 4.16. In all cases, the command line is like: "(path/project).uproject" -run=Cook -NoLogTimes -TargetPlatform=IOS -fileopenlog -unversioned -ski ...
Spot Light USD Export Produces Incorrect Intensity Values Based on Cone Angle and Source Radius
UE - Editor - Content Pipeline - USD - Apr 3, 2026UPDATE: Should be fixed as of CL#52537078 (fb7af1) USD: Bake all frames of exposure animation tracks. When exporting Unreal Engine spot lights from a level to USD, lights with identical EV intensit ...
SteamVR turns off vsync globally
UE - Platform - XR - Feb 21, 2020Additional Info From User: Result: Vsync will get turned off by FSteamVRHMD::Startup() setting a global console variable, regardless of your project configuration. Expected: Vsync is only deacti ...
Linux: Assertion at splash screen when trying to open UE4Editor
UE - Platform - Linux - Mar 21, 2017I ran into this while looking to verify [Link Removed] at CL 3355923. I logged the issue I was verifying the fix for last night and have not updated anything locally, so the "OpenGL 4.3 not supporte ...
Inconsistent ListView entry sizes can prevent the ListView from being scrolled to the bottom
UE - Editor - UI Systems - Slate - May 4, 2022Since the contents of a ListView are virtualized, the ListView estimates the size of the scroll box's contents based on the on-screen elements. This can lead to some situations where DistanceFromBot ...
Composite font uses a sub-font, even when the sub-font doesn't support the character
Tools - Apr 7, 2016I have a fix for this shelved in CL# 2937344, so it would be good to get it into 4.12 once the user verifies the fix. ...