Atmosphere related scan line artifacts for Path Tracer with MGPU

UE - Graphics Features - Path Tracer - Feb 10, 2023

There are two UDNs related to this issue.  It makes the Path Tracer unusable with MGPU, with atmosphere enabled. I already have a one-line fix implemented and tested.  The atmosphere scan line arti ...

Importing static mesh while a PIE session is running permanently breaks nanite on the asset

UE - Editor - Content Pipeline - Import and Export - Mar 12, 2025

Importing a Static Mesh during PIE can cause it to never enable Nanite, even if it reports that Nanite is enabled. To re-enable Nanite on the mesh, the asset needs to be deleted and imported again ...

HLSLCC crashed on parsing UAV related instruction

UE - Graphics Features - Oct 10, 2019

1.glsl_type with image was not fully inited with HlslName field set, causing the crash 2.seems many types of op are not support by current hlslcc, cause error msg. e.g. RWTexture2D.Load[Image Remo ...

AI Perception Peripheral Vision Angle Degrees Being Doubled

UE - AI - Jun 7, 2016

Any value that is set for Peripheral Vision Angle Degrees in an AI Perception component's Sight config is doubled. This does not occur with the PawnSensing component, which is inconsistent behavio ...

Custom Nav Area Not Affecting Nav Mesh Until Restart

UE - AI - May 2, 2016

When using a Nav Modifier volume with a custom Nav Area class, the Nav Mesh is not being affected until the editor is restarted. Found in 4.11.2 binary. Reproduced in 4.12 Preview 1 binary and Main ...

Building for Gear VR Distribution fails due to missing Oculus lib

UE - Platform - XR - Jun 7, 2017

Users have reported that building for Distribution on Gear VR results in failure due to a missing Oculus library. The error they receive is as follows: UATHelper: Packaging (Android (ETC2)): [javac ...

Moving Landscape causes Crash with Landscape Grass Output in Landscape Material

UE - LD & Modeling - Terrain - Landscape - Jun 16, 2016

Editor crashes when utilizing the Landscape Grass Output node within a Material, and then attempting to move the landscape with the material applied. I narrowed this down to being directly related ...

Set Component Tick doesn't work on Cascade Particle Systems

UE - Niagara - Jul 31, 2019

Changing the Component Tick Interval via Blueprints has no effect on Cascade particle system components. Tested in 4.21.2 (CL - 4753647), 4.22.3 (CL - 7053647), 4.23 P3 (CL - 7445012), 4.24 (CL - ...

Behavior Trees cannot be saved if the Blackboard assigned to it was opened before opening the Behavior Tree from the Content Browser

UE - AI - Nov 2, 2015

Behavior Trees cannot be saved if the Blackboard assigned to it was opened before opening the Behavior Tree from the Content Browser. Reproduced in 4.8.3 binary, 4.9.2 binary, 4.10 Preview 3 binary ...

[Audio][Niagara] - Audio Spectrum only reacts to Channel 0, despite setting to another channel

UE - Audio - Submixes - Jun 6, 2023

While doing some extra testing of the Submix Analyser fixes, I noticed there is a setting to set the channel of the submix to give the analyser. It always works for channel 0, but changing it to any ...