Unreal Engine Issues
Unreal Engine Issues
Translucent Materials and Atmospheric Fog Appear Black or Pink on Mac
UE - Graphics Features - Jan 3, 2018I tested this on a Mac Pro in UE 4.15, 4.16, 4.17, and 4.18. As a possible workaround for the fog issue, I've discovered that setting Atmospheric Fog > Lighting > Disable Ground Scatter to "True" wi ...
Loading instanced static mesh causes memory leak in packaged game
UE - World Creation - Worldbuilding Tools - Foliage - Mar 3, 2021The leaking variable is UInstancedStaticMeshComponent::InstanceDataBuffers. The memory block is passed to InitPerInstanceRenderData() via InstanceDataBuffers.Release(). But the function doesn't mana ...
Saving Level changes the Rotation of actors with parent-child relationships
UE - Gameplay - Components - Nov 14, 2019According to the licensee report, UnrealMath.cpp (588) constfloat SINGULARITY_THRESHOLD = 0.4999995f; It seems that this can be avoided by changing the above value. However, changing SINGU ...
Large Memory Allocations When Adding a Landscape_WaterBrushManager
UE - Graphics Tools - Terrain - Mar 17, 2025When a "Water Body River" is added to a Scene with a Landscape, eleven Render Targets are allocated for the water rendering. These Render Targets are sized according to the resolution of the Landsca ...
Mac - Inconsistent results for Lumen renders
TM - Rendering - Jun 3, 2025Reported in SF [Link Removed] and [Link Removed] Users on Mac are reporting inconsistent rendering results for Lumen in image exports that do not include any settings changes. When exporting some ...
Sequencer crashes when scrubbing characters with sub-anim instances and montage slots
OLD - Anim - Oct 2, 2019I saw a following assertion. Assertion failed: (AdditivePoses.Num() > 0) || (NonAdditivePoses.Num() > 0) [Link Removed] [Line: 1381] This is my quick fix// code placeholder void FAnimInstance ...
Mobile Preview -> AutoLandscape Material broken if created in 4.22+
UE - Platform - Mobile - Oct 25, 2019Landscape Layers created in 4.22+ revert to default material in Mobile Preview. Confirmed in MAIN at CL 9730599 ...
[CrashReport] UE4Editor_UMG!TBaseDelegate<FMargin>::operator=() [delegatesignatureimpl.inl:381]
UE - Editor - UI Systems - Aug 29, 2017This is a longstanding and common UMG crash that has affected more than 200 users since at least the 4.15 release. User DescriptionsI was working in the UI and undid several last changes in quick s ...
[CrashReport] UE4Editor_WorldBrowser!FMulticastDelegateBase<FWeakObjectPtr>::RemoveAll() [multicastdelegatebase.h:81]
UE - World Creation - Worldbuilding Tools - World Composition - Nov 2, 2017This is a trending crash coming out of 4.18 and may be a regression. Users have not provided any descriptions of their actions when the crash occurred. Source Context 72 /** 73 ...
CharacterMovementComponent boosted upward when falling into acute-angle sloped corner
UE - Gameplay - Player Movement - Apr 14, 2026In UCharacterMovementComponent::TwoWallAdjust, characters can gain unintended upward velocity (slope boosting) when hitting corners with an acute angle (<=90 degrees) while in the Falling movement m ...