Unreal Engine Issues
Unreal Engine Issues
Hot Reloading from IDE fails
UE - Foundation - Core - Jul 13, 2016Building from VS causes the compilation to fail. (Have not had the opportunity to check XCode yet, investigating) Found in //UE4/Dev-Core @ 3048370 Currently occurs in //UE4/Main @ 3049508Severity ...
Children of editor-only actors do not maintain correct transforms when placed inside level instances for PIE and cooked builds
UE - World Creation - Worldbuilding Tools - Level Instances - Oct 20, 2025We have found an issue where children of editor-only actors get wrong transforms in PIE and cooked builds when placed inside level instances. This affects both engine version 5.5 and 5.6. The issue ...
[CrashReport]UnrealEditor-Chaos!Chaos::TEventContainer<Chaos::FCollisionEventData>::DispatchConsumerData() [EventManager.h:214]
UE - Runtime - Simulation - 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 ...
Editor Crashes When Duplicating Actor that Contains Additional Components
UE - Gameplay - Dec 11, 2015Attempting to spawn a copy of an actor that has components that were added to an instance of that actor in the level causes a crash. Spawning the actor without adding additional components to the in ...
Nanite Displacement Bounds Mismatch Causes Floating Terrain Artifacts on Landscape
UE - Rendering - Graphics Features - Nanite - Mar 19, 2026Summary When Nanite Tessellation (Nanite Displacement) is enabled on a Landscape in UE 5.7.3, scaling the Displacement value via Multiply nodes in the material graph causes floating terrain ghost a ...
Niagara Scalability Crash When Processing Significance
UE - Niagara - Jun 4, 2025Method FNiagaraScalabilityManager::ProcessSignificance() iterates on indices from Context.SignificanceIndices and uses them to access the State and ManagedComponents arrays. It can then decide to cr ...
Mesh Vertex Painting Broken for Splines
UE - Rendering - Architecture - May 22, 2023The mesh painting mode appears to no longer work on splines, as the vertexes seem to have all vertex colors at 1, 1, 1, 1 by default, and can't be removed or painted anything else. ...
Bug in StringTemplate.cpp related to modulo operator in MaterialTemplate.ush (code fix provided)
UE - Rendering - Architecture - Materials - Jun 25, 2024Shader Template files like MaterialTemplate.ush do not submit previous chunks when encountering a `%` character, unless that `%` character is `%s` or `% {...} `. Because the error is happening ...
DestructibleMesh does not correctly effect vertex color of material.
UE - Simulation - Physics - Destruction - Oct 10, 2017Destructible Mesh does not correctly affect vertex color. ...
Crash launch application adding .umap url
UE - Foundation - Core - Aug 6, 2020The application crashes when adding ".umap" to the launch map at application launch. If not specify ".umap", it will be able to launch application. There appears to be a failure to parse the URL. Th ...