Unreal Engine Issues
Unreal Engine Issues
LandscapeMountains demo has large performance drops at various locations around map
Docs - Samples - Dec 2, 2014Landscape Mountains experiences heavy performance drops at various locations on map, specifically around ice lake in middle of map or when crashing. FPS varies from 50 FPS down to 11 FPS. ...
Editor Performance drops when removing frames from animations with curve data
OLD - Anim - May 26, 2016Editor Performance drops when removing frames from animations with curve keys Regression: No, removing frames on animations with curves had a chance to crash the editor in 4.11, which doesn't happ ...
Performance drop when spawning AI actors during runtime compared to placing them in world
UE - AI - Jan 9, 2019There is a performance difference between spawning and placing AI into a level. This is causing issues when spawning/despawning AI actors in a large open world, where 4-5ms of frame time quickly bui ...
Shadow casting still considered for performance when light intensity set to 0.0
UE - Graphics Features - Sep 8, 2016Shadow casting is still considered when the lighting intensity has been set to 0. This is a regression in performance from 4.12.5 where a lights intensity that was set to 0 would not be considered ...
Hot reload can no longer be performed after adding an empty class to a Blueprint-only project
UE - Foundation - Core - Feb 7, 2019Adding an empty code class to a Blueprint-only project prevents the project from being able to perform any hot reloads. When clicking the Compile button in the Editor, a warning is added to the log ...
Performing a Clean on a project using a binary Engine installation on Mac removes some Engine .dylib files
UE - Foundation - Core - May 17, 2018When a Clean is performed on a code project that uses a binary Engine installation on a Mac, some of the Engine's .dylib files are removed during the Clean process. A Clean process for a project usi ...
Using High Resolution Screenshot while the viewport is in Full Screen causes massive performance issues after the screenshot is successfully taken until the Editor is restarted
UE - Graphics Features - Jan 6, 2022This is a regression. Maybe Binary only if it hasn't already been fixed. Tested in:StreamCLTypeResults//UE5/Main18386535PerforcePerformance is normal after screenshot//UE5/Main18218925Perforce Per ...
Performance issue with the material dock
TM - Tools - Oct 1, 2025See video. Tested on 2025.2 In a project where you have a lot of materials, it take a long time to open the material dock. Here around 20 seconds. And that's at each time you want to enter it. Y ...
Performance decreases with the number of morph targets
UE - Anim - Rigging - Jun 15, 2023Performance decreases quite a bit on characters with large number of morph targets, as soon as even one target is active. ...
Strange performance when adjusting r.ScreenPercentage
UE - Graphics Features - Apr 6, 2021A UDN user has reported strange performance characteristics with occlusion queries / lights when using screen percentage. It appears using a higher screen percentage is faster; the user attached a s ...