Bright Flickering or Black Squares with Rectangle Lights Intersecting Meshes

UE - Graphics Features - May 31, 2024

Rect Lights that intersect geometry can produce NaN pixels in SceneColor, which will affect bloom, FXAA, and other future passes. This can lead to large visible artifacts. The NaN values are produc ...

Using ServerTravel from a map set as the Transition Map with Seamless Travel enabled in the Game Mode will crash the editor

UE - Gameplay - Mar 6, 2015

Using ServerTravel from a map set as the Transition Map with Seamless Travel enabled in the Game Mode will crash the editor. Probably related to [Link Removed] Reproduced in 4.7.2 binary and Main ...

Foliage Not Updating to Match New Landscape Height After Level Save-As

UE - World Creation - Worldbuilding Tools - Foliage - May 3, 2018

I have observed this behavior in 4.18.3, 4.19.2, and Main (CL 4048405) Per User: I made a landscape, painted some foliage and saved the scene. After I saved the same scene under different name the ...

Materials for certain groups appear black in Path tracer when "Keep hierarchy" is used to import .skp files.

TM - Interoperability - Mar 3, 2025

Reported by a client in SF [Link Removed] When importing SKP files using the Keep Hierarchy collapse mode, some imported objects in Groups inside SketchUp will appear black in Path Tracer. Appears ...

BSOD when launching Twinmotion on NVIDIA 50-series GPUs with 576.02 Drivers

TM - Rendering - Apr 22, 2025

Reported from multiple users. NVIDIA RTX 50-series GPU users are reporting BSODs when attempting to launch Twinmotion with the latest drivers installed. The crashes occur on the 576.02 driver versi ...

Fail to compile with Added AIController class

UE - Foundation - Core - Jan 14, 2015

User fails to compile code template after adding AIController code to project. Regression: Not a regression happens in 4.6.1 CL-2386410 Setting up Mono Building MyProjectEditor... Compiling game m ...

Foliage frustum cull based on incorrect bounds size

UE - World Creation - Worldbuilding Tools - Foliage - Aug 22, 2016

When changing the static meshes of a Foliage instance by swapping the mesh or changing the scale (build settings) of the mesh, the bounds for the mesh do not appear to update to use the new bounds. ...

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, 2024

The 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 ...

Simulated ability tasks not being cleaned up in UActorChannel::ReplicationMap

UE - Networking - Nov 20, 2018

I've noticed the issue occurring in both 4.20.3 (CL 4369336) and 4.21.0 (CL 4541578). The user on AnswerHub has also noticed the issue in 4.20.2 (CL unknown) and claims the issue did not occur in 4. ...

Lighting data wiped if sub level is hidden while rebuilding lighting for visible levels

UE - Graphics Features - Jan 11, 2017

When building lighting now you can no longer have a hidden sub level and have it retain it's built light if it was previously built. For instance, if you have a persistent level and hide the sub-lev ...