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 ...
Launch on fails during staging with a SafeCopyFile Exception for MfMedia.uplugin
Tools - Jan 10, 2017Was able to repro this on machines with and without machines set up for Xbone testing. ...
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 ...
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 ...
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. ...
MotionWarping does not recognize new MontageInstance with the same montage
UE - Anim - Gameplay - Jan 11, 2023When the same AnimMonotage is played again while moving with MotionWarping & RootMotion, UAnimNotifyState_MotionWarping does not recognize it. From licensee: The issue was that in URootMotionMod ...
UAssetManager::ChangeBundleStateForPrimaryAssets: Performance: Avoid canceling loads in progress when new bundles added and the in progress bundles are kept
UE - Foundation - Data Pipeline - Cooker - Mar 4, 2024UAssetManager::ChangeBundleStateForPrimaryAssets allows adding new BundleNames to the list of BundleNames loaded for a PrimaryAssetId. Each BundleName specifies a BundleEntry with a list of assets. ...