Unreal Engine Issues
Unreal Engine Issues
Blueprint processing is heavy in PIE since 4.26
UE - Gameplay - Blueprint - Feb 17, 2021As the attached image shows, there is no problem in 4.25.4, and the process is noticeably slower in 4.26.1. Also, there is no problem in Standalone. The problem occurs only in PIE. ...
Volumetric Clouds High Quality Aerial Perspective Issue
UE - Rendering Architecture - Oct 19, 2023There is a workaround to set r.VolumetricRenderTarget.Mode=1. The lines appear to be coming from the temporal component of the Volumetric Clouds. Each frame, the lines are merged in from the previou ...
Editor Crashes when working in QAGame TM-Sequencer_EventTrack - TCString<TCharType>::Strlen(InName)
UE - Anim - Sequencer - Jul 12, 2017Editor Crashes when working in QAGame TM-Sequencer_EventTrack - TCString<TCharType>::Strlen(InName) This Assert happens randomly throughout the repro-steps. I am unsure what about the process cause ...
Blueprint Launches onto tvOS fail during runstep: Error_DeviceOSNewerThanSDK
UE - Platform - Mobile - Apr 19, 2019When a user launches blueprint project to a tvOS device they will fail to run the project during the run step and if they manually try to launch the app from the dashboard. This issue does not repr ...
Assets on paths with speed parameters are sped up in Path Tracer exports
TM - Rendering - Jul 18, 2025Reported in SF [Link Removed] In Path Tracer renders, all paths with a speed component (vehicles, bicycles, custom) will render at an increased speed than specified in the exported render. This is ...
Conflict between sequencer transform track and Parent Constraint from the Animation Mode breaks temporary pivot translation on any actor
UE - Anim - Anim in Engine - Jul 15, 2025Note: This affects all versions from at least UE 5.3, including mainline latest. The "Animation" Editor Mode allows creating constraints for level actors. One of these, the "Parent" constraint, con ...
Property Editors fail to import text values for FKeys within array/set/map containers when the key is identified by some valid non-alphanumeric characters
UE - Gameplay - Input - Oct 28, 2024The FKey structure represents a user action input such as a keyboard key, a mouse button/wheel, or a gesture in VR. For the keyboard, it can represent any pressable key, such as letters, numbers, sy ...
The Remove-On-Break feature, set on Fracture Mode on Geometry Collections, stops shrinking and shows strange behaviors
UE - Simulation - Physics - Destruction - Oct 15, 2024The Remove-On-Break (ROB) feature, set on Fracture Mode on Geometry Collections (GC), was supposed to make the particle shrink until it vanishes. When the GC goes to sleep the shrinking stops and sh ...
Niagara - When Interpolated Spawning is disabled, the first frame of each particle unexpectedly does not take into account the Particle Update stage
UE - Niagara - Feb 28, 2025Foreword: Even if the behavior described here is by design, it is rarely (if ever) expected or desired. This was discussed and agreed to be treated as a bug. Explanation below. When interpolated sp ...
Instanced Static Mesh does not apply World Aligned Material correctly
UE - Graphics Features - Aug 22, 2016If you apply a material that uses World Aligned Blend to an instanced static mesh, it will display differently than an non-instanced static mesh with identical settings. They only look identical if ...