Unreal Engine Issues
Unreal Engine Issues
SAnalogSlider moves slowly when step size is large
UE - Editor - UI Systems - Slate - Mar 6, 2024SAnalogSlider calculates FastestStepTime by multiplying the step size value by a constant, resulting in high numbers for larger step sizes. This gets lerped from 1 and used as the repeat time, resul ...
CitySample - Level MassCrowd - interactions with SmartObjects/ContextualAnimScene is broken in 5.5
UE - AI - Apr 9, 2025The 5.5 version of the CitySample project, particularly the MassCrowd scene, was not properly maintained. The previously working functionality of NPCs being able to sit on a bench is now broken. CAS ...
Sequence with Override Instance Data enabled and a SubShot will accumulate the TransformOrigin Location wrongly and overshoot the expected end position
UE - Anim - Sequencer - Mar 28, 2025A Sequence with Override Instance Data enabled and a SubShot will accumulate the TransformOrigin Location wrongly and overshoot the expected end position. The licensee has encountered a particular s ...
World Partition - Deleted actors can become unloaded prior to saving
UE - World Creation - Worldbuilding Tools - World Partition - Apr 11, 2025In world partition levels, deleted actors can become unexpectedly unloaded prior to saving, causing loss of work. Specifically, this issue occurs after the undo history has been cleared (either manu ...
Merging Splines causes Engine to Crash in 5.1
UE - World Creation - Worldbuilding Tools - Merge Actor - Dec 15, 2022Attempting to merge two spline actors causes the Engine to crash. This issue occurs with the Steps to Reproduce regardless if there are more branches added to the tree branch spline/enabled, and reg ...
ConfigContext on linux requires perforce path for defaults.global.json when global is perforce resolved
UE - Foundation - Horde - Server - Mar 7, 2025As of 5.5.2; appears present in main head as well. We have a asymmetry between how Include JSONs are resolved between Linux and Windows. This boils down to our URI construction in ParseIncludesAsyn ...
[AI] WP Dynamic navmesh fails to rebuild tiles with actors that are loaded but not part of the base navmesh.
UE - AI - Navigation - Feb 18, 2025WP dynamic navmesh does not properly react to actors or navigation modifiers that are loaded in areas that the navmesh has not yet streamed into. Although the actors/modifiers are not part of the ba ...
Non-existing config file loading could cause memory leak
UE - CoreTech - Oct 19, 2023The cause of this problem is the Engine has code paths which register a new allocated object to Map without deleting the previous object. In the repro project, whenever hitting Space Bar, the level ...
Chaos Trailing Events not exposed to Blueprints and only accessible via Niagara Chaos DI
UE - Simulation - Physics - Destruction - Apr 22, 2025Chaos Trailing Events not exposed to Blueprints and only accessible via Niagara Chaos DI. The licensee noticed that the Trailing event is not available to BPs. It's expected that the same data avail ...
UNetDriver server-side hitch results in ActorInfo->NextUpdateTime far into future
UE - Networking - Feb 16, 2024A high UWorld::Tick DeltaSeconds (i.e. GameThread hitch) results in a high UNetDriver::TickFlush DeltaSeconds. This DeltaSeconds can high (many seconds) if the hitch is long. This value then affects ...