Unreal Engine Issues
Unreal Engine Issues
Mirror operation on Physics Asset produces wrong results for constraints, including flipped axes
UE - Simulation - Core - Feb 7, 2025The Physics Asset Editor has a "mirror" feature that allows physics bodies and constraints to be mirrored from one side of a skeleton to the other. If this operation worked correctly, it could save ...
Lyra 5.5 - LAS_ShooterGame_SharedInput has got a missing reference on InputMapping #1
UE - Gameplay - Input - Jan 27, 2025The templated Lyra project for 5.5 is missing a reference to IMC_Default_KBM on /ShooterCore/Experiences/LAS_ShooterGame_SharedInput because it looks like IMC_Default_KBM was renamed to IMC_Default. ...
Level Actors that are converted to a Blueprint using "Convert Selection to Blueprint Class" and using "Harvest Components" as the CreatingMethod, does not sanitize dots (.) character and make them invalid for operations like StaticFindObject.
UE - Framework - Blueprint Editor - Feb 20, 2025When Level Actors are converted into a Blueprint using the "Convert Selection to Blueprint Class" option with "Harvest Components" as the creation method, the conversion process does not sanitize do ...
Physics Constraint Component loss of accuracy
UE - Simulation - Core - Mar 6, 2025Physics Constraint Component has lost accuracy between Unreal versions 5.2 and 5.4 (and up). When measuring the exact distance between rigid bodies constrained by a Physics Constraint Component, the ...
Popping Ribbon UVs
UE - Niagara - Mar 10, 2025Please see the Additional Link for related UDN information. The UV popping described can be subtle, depending on settings; it's affected by spawn rate and GPU vs CPU. The popping shown in the gif t ...
Crash in FUniformExpressionSet::FillUniformBuffer trying access deleted UTextureCollection
UE - Rendering - Architecture - May 30, 2025Crash in FUniformExpressionSet::FillUniformBuffer trying access deleted UTextureCollection (Experimental in 5.6). The licensee describes their crash, their analysis, and a proposed fix: This crash ...
DynamicEntryBox with EntryBoxType Radial is stacking Entries if SectorCentralAngle is multiple of 360.0f and DistributeItemsEvenly is enabled
UE - Editor - UI Systems - May 27, 2025DynamicEntryBox with EntryBoxType Radial is stacking Entries if SectorCentralAngle is multiple of 360.0f and DistributeItemsEvenly is enabled. The licensee has provided an analysis: On void SRadia ...
Runing PlayInEditor with NetMode PlayAsClient and a LevelSequence that AutoPlays in the level and is also opened in Sequencer leads to a Fatal world leak crash on 5.5 and up
UE - Anim - Sequencer - May 28, 2025Runing PlayInEditor with NetMode PlayAsClient, a LevelSequence that AutoPlays in the level, contains a Spawnable BP_ThirdPersonCharacter with an animation, and is also opened in Sequencer, leads to ...
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 ...
Niagara Regression - Looping particle with Spawn Burst Instantaneous on time 0.0 flickers for a frame between loops
UE - Niagara - Jul 16, 2025Note: This worked correctly up to UE 5.4, but repros from UE 5.5 up to mainline latest. If a Niagara Emitter is set up with "Spawn Burst Instantaneous" on time 0.0, and the spawned particle(s) have ...