Unreal Engine Issues
Unreal Engine Issues
ensure(false) being fired in FGenericParticlePairMidPhase::FindOrCreateConstraint from key collision
UE - Simulation - Physics - 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 ...
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. ...
Sequencer - When a subsection has negative play rate, any nested sub-subsections fail to evaluate
UE - Anim - Sequencer - Jul 3, 2025Consider a sequence hierarchy with more than two layers. If the top-level sequence uses a negative timescale on a sub-sequence, the contents inside it animate as expected, but any nested sub-sequenc ...
[CrashReport] Mac crash - UE4Editor-Slate.dylib!SMenuAnchor::SetIsOpen()
UE - Platform - Apple - Sep 14, 2017This is a common and longstanding Mac crash that has occurred since at least 4.11 and affected more than 40 users. Users have not provided any descriptions of their actions when the crash occurred ...
[CrashReport] ULevel::GetWorldSettings - UMaterialFunctionThumbnailRenderer::Draw
Tools - Oct 30, 2017This is a common crash that has occurred since at least 4.16. The callstack is nearly identical to [Link Removed], which appears to be fixed in 4.18; and [Link Removed], which has not. The differen ...
Unknown force is applied to the cloth when changing the skeletal mesh LoD with cloth.
UE - Simulation - Physics - Character - Jul 11, 2019There are 3 issuesEach particles don't restore its previous position. Which is for calculating velocity by verlet iteration.The previous transform is cleared by current transform. It provides zero v ...
MovieRender Pipeline Skips Output Frames during GC
UE - Anim - Sequencer - Jun 8, 2020This is being seen in the wild... can release a temporary fix until 4.26 when we can change the headers and fix it for real. ...