Camera Movement is laggy while the mouse button is held down and ShowMouseCursor is enabled if there are AI moving

UE - Gameplay - Dec 15, 2015

Camera Movement is laggy while the mouse button is held down and ShowMouseCursor is enabled if there are AI moving. Stat Scene Rendering didn't show any jumps while moving the camera under these cir ...

PhysX Crash when spawning Instanced Static Mesh actors at Runtime

UE - Simulation - Physics - Destruction - Oct 13, 2015

Bug generated from crash reporter. This crash has been found in 4.7.6 and still occurs in 4.8.3 and 4.9.2 to users. One user in particular still, and he experiences it often. I have not been able ...

Compiler error after changing the class in a Spawn Actor from Class node, undoing with Ctrl + Z, refreshing the node, and reconnecting exposed variables

UE - Gameplay - Blueprint - May 26, 2015

Compiler error after changing the class in a Spawn Actor from Class node, undoing with Ctrl + Z, refreshing the node, and reconnecting exposed variables. "Error Internal compiler error inside Creat ...

Shipping build crash when unplugging then replugging Oculus HMD

UE - Platform - XR - Nov 9, 2016

Game crashes in shipping build when un-pluging the Oculus HMD, then plugging it back in. Confirmed in 4.13.2 from the launcher, did not repro via same steps in 4.14 preview 3 ...

Rendering of a Text Widget with Outline does not track LayerId correctly

UE - Editor - UI Systems - May 27, 2025

Text widget with Outline uses 2 LayerId levels to draw the outline and the text glyphs. This can be seen in function FSlateElementBatcher::AddShapedTextElement(), where lambda BuildFontGeometry() is ...

When using Perforce, saving a level over another leaves the target umap file as "marked for delete"

UE - Editor - Workflow Systems - Mar 11, 2025

When working on a level asset and using command "File – Save Current Level As..." to save it over a different level asset, the engine first deletes the target level (that's going to be overwritten) ...

Physics Asset details window jitters when shrunk.

Tools - Sep 29, 2014

Branch Build Label UE4-Main Promoted-CL- 2306964 DESCRIPTION: When using the vehicle template and having any wheel selected inside the physics asset, shrinking the size of the details window ca ...

[CrashReport] UE4Editor_Engine!FAnimCurveBase::SetCurveTypeFlag() [animcurvetypes.cpp:18]

OLD - Anim - Jun 13, 2016

This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Descriptions from users are provided below. Error message: Access violation - code c0000005 ( ...

Creating a copy of BSP after fliping it in geometry edit mode cause the copy to be invisible

UE - LD & Modeling - Modeling Tools - BSP - Aug 29, 2014

Branch Build Label UE4-Main Promoted-CL- 2270796 DESCRIPTION: If a player goes into geometry edit mode and flips a bsp then makes a copy of it the copy will appear invisible ADDITIONAL NOTES: A ...

Using a Macro to access a variable from another Actor causes a crash in Standalone

UE - Gameplay - Blueprint - Jun 8, 2015

Using a Macro to access a variable from another Actor causes a crash in Standalone. This does not seem to affect any other preview in editor, nor packaged games. Reproduced in 4.7.6, 4.8 Preview 4, ...