Unreal Engine Issues
Unreal Engine Issues
Different instanced materials are seen as the same material due to GUID
UE - Graphics Features - Jun 3, 2021See licensee description of the issue: The problem appears when I have two instanced materials with the same number of parameters. I've noticed that ShaderMapId has MaterialLayersParameterIDs where ...
Invalid GUIDs on new material instance parameters cause overrides to break on base param rename
UE - Rendering Architecture - Materials - Sep 3, 2025When a parameter value is assigned on a newly created material instance (constant or dynamic) using Set***ParameterValueInternal, the parameter’s ExpressionGUID is left invalid (0,0,0,0). Parameter ...
[VR] Camera attached to non-root scene component in BP will sink into floor after Reset to Floor Origin
UE - Platform - XR - Aug 12, 2016When a project is first created following the Setting up UE4 to work with SteamVR docs, the Vive camera works correctly and will display at the correct height. However, if at any point during develo ...
Upgrading project results in loss of game input
UE - Gameplay - Input - Jan 7, 2020Upgrading a marketplace creator's project to engine version 4.23.1 and above results in loss of (previously) working functionality with game input. ProjectDownload: [Link Removed] Tested in: 4.2 ...
Crash on play if a BP uses a ClearInstances node followed by an AddInstance node
UE - Graphics Features - Jul 21, 2017Crash on play if a BP manipulates a InstancedStaticMeshComponent by using a ClearInstances node followed by an AddInstance node. This is a blocker for the licensee. This is a regression: Working ...
Cannot access private member MarkPropertyDirtyFromRepIndex error when building a nativized blueprint with a replicated property
UE - Networking - May 14, 2020The following error occurs when building a project that has a replicated variable with the replication condition set to Skip Owner inside a nativized blueprint.UATHelper: Packaging (Windows (64-bit) ...
CheckForWorldGCLeaks crash using New Level from Template node to duplicate sublevel of the currently loaded level
Tools - Feb 23, 2021A world leak crash occurs when using NewLevelFromTemplate to duplicate a sublevel of the currently loaded level. The crash doesn't manifest until another level is loaded even though the Sublevel ins ...
Crash in FUniformExpressionSet::FillUniformBuffer trying access deleted UTextureCollection
UE - Rendering Architecture - May 30, 2025Crash in FUniformExpressionSet::FillUniformBuffer trying access deleted UTextureCollection (Experimental in 5.6). The licensee describes their crash, their analysis, and a proposed fix: This crash ...
Initializing custom Component on Actor in constructor causes odd hierarchy and details panel issues
UE - Gameplay - Blueprint - Feb 19, 2019When testing with a simple setup, as follows: MySceneComponent has a UProperty(VisibleAnywhere, BlueprintReadOnly) of a USphereComponent pointer, initiated in the Constructor AMyActor has a UProper ...
Focus mode in the Editor does not handle Actors without PrimitiveComponent correctly, treating them as if they were at the origin (0,0,0), skewing the camera placement.
UE - World Creation - Worldbuilding Tools - Nov 18, 2024Focus mode in the Editor does not handle Actors without PrimitiveComponent correctly, treating them as if they were at the origin (0,0,0), skewing the camera placement. Some Actors like the WorldDat ...