Unreal Engine Issues
Unreal Engine Issues
Crash when rendering cinematic in a Separate Process without "-NoLoadingScreen" cmd argument
UE - Anim - Sequencer - Jul 5, 2016Crash when rendering cinematic in a Separate Process without "-NoLoadingScreen" cmd argument. Occurs in 4.12 and 4.13 in both Matinee and Sequencer Error message: Assertion failed: SizeX > 0 && S ...
Lightmaps on Mobile Devices Appear Dirtied and Pixelated
UE - Platform - Mobile - Jun 19, 2015Baked lighting on mobile has dirtied or pixelated lightmaps. When testing this issue I attempted to change various settings within the 'Lightmass' section and the changes made did not have much effe ...
Lumen Global Distance Field Trace Leaking due to Surface Cache Sampling
UE - Graphics Features - Jan 12, 2026At specific distances from a thin wall, surfaces inside of a sealed chamber can receive indirect lighting from outside, leaking light into the chamber. This appears to be due to how SWRT handles sa ...
Crash when using Mesh Reduction on ScotsPine_01 for LOD3
UE - Graphics Features - Jan 30, 2017A crash occurs when trying to use the Mesh Reduction tool for the ScotsPine_01 static mesh from the Open World Demo collection. The assets from this project are usually very processor heavy due to ...
When very far out from the map origin, large static mesh is not streaming in until player is close in world partition even though it's within loading range.
UE - World Creation - Worldbuilding Tools - World Partition - May 7, 2025Context World Partition has a distance-based level streaming system that provides a complete solution for large world management. Problem The problem is that when the player and large static mesh a ...
Costs of Static Lights on Render Thread
UE - Graphics Features - Jun 9, 2016A Japanese developer's making a scene that has over 4000 static point lights. They thought the lights don't affect rendering in runtime. But they realized the RenderThread's costs become bigger. I ...
[CrashReport]UnrealEditor-Chaos!Chaos::TEventContainer<Chaos::FCollisionEventData>::DispatchConsumerData() [EventManager.h:214]
UE - Simulation - Physics - Mar 14, 2022Generated from CrashReporter Error Messages:Assertion failed: (Index >= 0) & (Index < ArrayNum) [File:D:\build\++UE5\Sync\Engine\Source\Runtime\Core\Public\Containers\Array.h] [Line: 691] Array ind ...
Play Media Player Node Causes Blueprint Functions to be Uncallable
UE - Gameplay - Blueprint - Feb 23, 2016This only occurs in standalone or a packaged game Having a Play Media Player node in a blueprint causes all of that blueprint's functions to become uncallable. Found in 4.11 Preview 5. Reproduced ...
Vulkan leaks memory when opening and closing windows
UE - Rendering Architecture - RHI - Nov 22, 2019As described here: https://udn.unrealengine.com/questions/532725/index.html (1) Start Prebuilt Vanilla 4.23.1. with Vulkan enabled (2) Create a new project (3) Drag and drop the Sphere from “modes ...
Crash when Applying Hole Material to Imported Tiled Landscape with World Composition
UE - LD & Modeling - Terrain - Landscape - Jun 11, 2015A crash occurs when importing a tiled landscape, via the 'Levels' window with World Composition enabled, and applying a material to the 'Hole Material' slot. You can also re-apply a default material ...