Unreal Engine Issues
Unreal Engine Issues
Changing blueprint default values inside arrays only updates loaded child blueprints
UE - CoreTech - Jul 30, 2020The rules for delta serialization in UE4 are complicated, and the editor tries to hide them from you, which works 90% of the time but can lead to confusion and data loss in other situations. In the ...
Cannot select child anim BPs for use in linked anim layers
UE - Anim - Runtime - Jul 15, 2021From UDN: [Link Removed] Unable to set a Child ABP with inherited interface to a Linked Animation Layer Instance Class. I have a ABP_Biped which is our main ABP. I have the locomotion (idle+straf ...
[CrashReport] UE4Editor_CoreUObject!FPackageName::LongPackageNameToFilename() [packagename.cpp:381]
Tools - Jul 14, 2017This is a common crash affecting users in 4.15 and 4.16. It appears to often occur while editing static meshes. User DescriptionsI was editing a mesh, added a socket, didnt immediately rename it, s ...
Instanced Static Meshes ignore max World Position Offset Displacement for bounds after UpdateInstanceTransform is called
UE - Graphics Features - Jun 18, 2025When an Instanced Static Mesh Component (ISMC) uses a material with a non-zero Max World Position Offset Displacement, the bounds are correctly expanded at initialization. However, after calling Upd ...
Render target size mistmatch in ShaderDrawDebug
UE - Graphics Features - Jun 9, 2020We found a d3d debug validation assert in RDG_EVENT_NAME("ShaderDrawDebug"), with the full DLSS integration. It however also reproduces in (4.25.1-release, dev-rendering and the plugin branch with ...
Wrong density calculation in UBodySetup::CalculateMass
UE - Simulation - Core - Sep 29, 2025Wrong density calculation in UBodySetup::CalculateMass. The licensee has provided the following analysis and suggested fix: In UBodySetup::CalculateMass, the following code is present: // physical ...
Unwanted black boundaries are displayed in a vertical split-screen with 3 players.
UE - Gameplay - Dec 2, 2019Floating point error from UGameViewportClient::SplitscreenInfo causes this issue. FMath::TruncToInt( 3240 /*ViewportSize*/ * 0.333f/*Ratio in SplitScreenInfo*/ ) = 1079 I suggested a following t ...
[CrashReport] UE4Editor_D3D11RHI!VerifyD3D11CreateTextureResult() [d3d11util.cpp:276]
UE - Graphics Features - Mar 30, 2017This crash seems to be related to or a continuation of [Link Removed], where that specific CrashGroup stopped receiving new crashes after the 4.10 release. This one has occurred from 4.13 - 4.15 (s ...
Editor crash on level load when bUseActorFolders is true after dragging Actor into another folder in the Outliner
UE - World Creation - Worldbuilding Tools - OFPA - Mar 7, 2023From licensee: Hello! Our level streaming setup enables the bUseActorFolders on our levels. When moving the Actor into another folder via the Outline, the editor will crash on the next load Assert ...
5.5 Static Mesh Import Pipeline Regression
UE - Editor - Content Pipeline - Import and Export - Apr 25, 2025This question was created in reference to: [Link Removed] This post references the first post because this problem was not discovered till now. I think it was masked because the issue appears to be ...