Crash on startup with a Blueprint deriving from an abstract class with a SpriteComponent

Tools - Feb 7, 2018

Appears to be an issue with load order and the timing of when we populate the 'ShowSpriteCommands' and 'SpriteIDToIndexMap' containers, which we assert on if they're not the same size. The original ...

The ChaosCacheManager changes the bSimulatePhysics flag from the ObservedComponents and, if deleted, the change will persist, what can lead to confusion as observed physical entities will inadvertently stop simulating physics

UE - Simulation - Physics - Nov 26, 2024

The ChaosCacheManager (CCM) changes the bSimulatePhysics flag from the ObservedComponents and, if deleted, the change will persist, what can lead to confusion as observed physical entities will inad ...

Mouse Not Functioning Correctly with Multiple Displays Connected to Mac

UE - Platform - Apple - Apr 24, 2015

When using mutliple monitors connected to a Mac the mouse behavior does not function well. Attempting to navigate and drag windows to and from individual displays proves difficult. The user reporti ...

The AABBTree spatial acceleration structure goes off-sync when physics substepping is enabled in a "low" framerate environment.

UE - Simulation - Physics - Mar 15, 2024

When you enable the physics substepping, if you run the console command p.Chaos.Solver.DebugDrawSpatialAccelerationStructure 1, you can see how does not follow the physical object. The user that rep ...

Consolidate tool fails to replace unloaded references to Material Instances

Tools - Feb 20, 2018

This issue is not a regression, it has been broken since the start of UE4. This bug may be related to [Link Removed] . Per licensee: We are trying to replace certain materials with material instan ...

Clear Coat looks incorrect in the Preview when Energy Conservation on Material is enabled for non Substrate rendering

UE - Rendering Architecture - Materials - Apr 11, 2024

Enabling Energy Conservation on Material makes Clear Coat Material look weird in Preview. It looks fine in the Level Editor, but not in any "Preview" type viewport (Material Editor, Asset Thumbnails ...

Foliage lightmaps for LODs does not look correct

UE - World Creation - Worldbuilding Tools - Foliage - Jun 21, 2016

When using the foliage tool with any mesh that has a LOD the lightmap generates artifacts for the instance. The base LOD will have correct looking lightmaps, however when pulling back and seeing the ...

[CrashReport] UE4Editor_Engine!UMaterialExpression::GetOutputType() [materialexpressions.cpp:859]

UE - Rendering Architecture - Materials - Nov 21, 2017

This is an infrequent crash in the 4.18 release. Users have not provided any descriptions of their actions when the crash occurred. Source Context 849 uint32 UMaterialExpression::GetOutputT ...

Sequencer autosorts alphabetically on undo

UE - Anim - Sequencer - Sep 8, 2023

[Link Removed] Jan Kaluza 2023-09-08 15:37:18 UTC I just ran into a very frustrating bug: I have around 60 actors in a sequence, and I reordered them to be in the order that I wanted to animate them ...

Stationary light shadow are occluded for additional players in split-screen mode

UE - Graphics Features - Jun 17, 2015

When using split screen multiplayer the second or more players that are added for split screen will have their characters shadows occluded when the bounds are not within view of player 1. Setting ...