Unable to affect setting cubemap blend in skyLight and reflections on transluscent materials

UE - Rendering - Architecture - Oct 17, 2023

Attempting to blend SkyLight Cubemaps via the SetCubemapBlend function to blend between different Cubemaps to make the changes seamless is not reflected. As a workaround, in LumenTracingCommon.ush, ...

Shadow Maps performance issue with 5.4 in comparison towards 5.3

UE - Graphics Features - Shadows - Nov 20, 2024

Shadow depths performance for non-VSM in certain scenes, notably those with rect lights and meshes that are set to movable, went from ~2ms to ~18ms going from UE 5.3 to UE 5.4. Setting the movable a ...

AnimNotifyState with the same class, but different content at the same time will only one be triggred

UE - Runtime - Animation - Oct 26, 2022

UDN Case : https://udn.unrealengine.com/s/question/0D54z00008G3EmwCAF/two-c-based-animnotifystate-with-the-same-class-but-different-content-at-the-same-time-will-only-one-be-triggred?fromCase=1 ...

Target Points are changing locations within World Partition Maps Shipping Build

UE - World Creation - Worldbuilding Tools - World Partition - Sep 19, 2023

Target Point Actors are changing location when in a World Partition Map within a Shipping Build. This does not occur in Non World Partition Maps. The name of the Asset also changes when in a World ...

Pathtracer - Odd results from any material adjusting normals to complement world position changes

UE - Graphics Features - Path Tracer - Sep 30, 2025

Someone on the forums is reporting a possible bug with Pathtracer and any material that adjusts normals to complement world position changes. See pic attached. Reporting forum thread:https://foru ...

GAS: Initial OnRep_SpawnedAttributes from DefaultStartingData clears attribute values for already replicated ActiveGameplayEffects

UE - Gameplay - Gameplay Ability System - Oct 23, 2024

Context The property 'DefaultStartingData' in AbilitySystemComponent can be configured from blueprint to spawn default attribute sets. This happens OnRegister. For runtime spawned actors like pawns ...

Multiplayer VR Preview Support Broken

UE - Platform - XR - Jul 11, 2016

The VR Preview used to work with multiple clients but now only works with the first client. This makes testing multiplayer features difficult or impossible as there is no way to change which client ...

Procedural Mesh Component 'Create StaticMesh' Function corrupts mesh tangents

UE - LD & Modeling - Modeling Tools - Mesh Editing - Oct 25, 2018

After clicking 'Create StaticMesh' button on an Procedural Mesh Component, and saving the mesh, the created mesh has bad tangents. Included in the attachments, is a test project with a parallax mate ...

Downsampled SceneColour textures are not invalidated after ComposeToNewSceneColor when TSR is enabled leading to AfterMotionBlur materials not rendering bloom

UE - Graphics Features - Sep 11, 2025

When an emissive AfterMotionBlur material is used with TSR, Bloom is not applied to the material. The cause for this appears to be that AfterMotionBlur materials are composed to a separate texture ...

TSoftObjectPtr does not replicate properly

UE - Networking - Nov 27, 2018

Right now USoftObjectProperty does not implement NetSerializeItem so it falls back to the implementation in UObjectPropertyBase. This only works correctly if the object happens to be in memory, othe ...