Incorrect Lumen Scene direct lighting when objects behind masked landscape

UE - Rendering - Graphics Features - Lumen - Oct 5, 2025

When objects are placed behind or beneath a masked landscape and r.Lumen.HardwareRayTracing.SurfaceCacheAlphaMasking is enabled, the direct light evaluation is incorrect. There are two workarounds, ...

Non-determinism in StaticMeshComponent::BodyInstance when cooking LevelInstances

UE - Simulation - Core - May 21, 2026

A licensee reported that serialization of LevelSequence with StaticMeshActor with default collision for which mesh has NoCollision profile is not deterministic. The issue seems to be in the fact tha ...

Ease node "Shortest Path" auto sets to true after closing and reopening editor

UE - Gameplay - Blueprint - Mar 9, 2015

UPDATE: 3/10/2015 User reported manually adding a separate boolean value causes that value to automatically switch to true upon reloading editor as well. No current workaround is available. ======= ...

BlackmagicMediaSource causes a memory leak if "Just-In-Time Rendering" option is ON.

UE - Virtual Production - Oct 31, 2023

Since 5.3, BlackmagicMediaSource causes a memory leak. This didn't happen on 5.2. You can see the leak on PIE. [Image Removed] [Image Removed] If "Just-In-Time Rendering" option in the MediaB ...

Landscape Grass Output Instances begin to float when using the Retopologize Tool

UE - LD & Modeling - Terrain - Landscape - Mar 14, 2017

When using the Retopolgize tool on a landscape that is utilizing the Landscape Grass Tool, any pre-existing grass types will begin to float and transform their locations. The only way myself and th ...

values for pinch input produce very different results for same area on android device

UE - Platform - Mobile - Oct 13, 2017

Values for pinch input produce very different results for the same area on an android device. values can range from 0 to 1, or end up in the thousands, despite the pinch distance being the same. It ...

Edit-> Project Settings -> Collision -> Presets Has No Scroll Bar

Tools - Sep 30, 2015

If you open a project and immediately go to Edit-> Project Settings -> Collision and expand the Presets dropdown, no scroll bar will appear. This prevents you from being able to see all of the optio ...

Instances of Blueprints implemented native interface cannot be assigned to interface variables

UE - Gameplay - Blueprint - Oct 28, 2021

FInterfaceProperty::SerializeItem (and ImportText) attempt to determine if the passed in object implements the interface in question. They do this by calling GetInterfaceAddress, which tries to get ...

Cook fails when a MetaSound Source object is referenced utilizing FObjectFinder in C++

UE - Audio - MetaSounds - Apr 27, 2022

Android Cook fails when a MetaSound Source object is referenced utilizing FObjectFinder in C++ Repro Rate: 3/3 UATHelper: Cooking (Android (ASTC)): LogInit: Display: LogMetaSound: Error: Target int ...

Runtime Virtual Texture (RVT) baked mips using Streaming Virtual Texture (SVT) only bakes the base colour

UE - Graphics Features - Sep 13, 2024

Using Streaming Virtual Textures for the lower mips of an RVT using Base Color, Roughness, Normal seemingly leads to both roughness and normal being sampled as 0. This causes a significant shading a ...