Unreal Engine Issues
Unreal Engine Issues
Each adding a static mesh not containing any collision data keeps increasing PhysX memory
UE - Simulation - Gameplay - Apr 19, 2021If the static mesh has UseSimpleCollisionAsComplex and does not have any SimpleCollision shapes, The physics actor will be destroyed immediately in FInitBodiesHelperBase::CreateShapesAndActors, but ...
Reference to control rig can be lost on actors with multiple skeletal mesh components
UE - Anim - Rigging - Control Rig - Apr 4, 2023In the attached project, when we initially add a control rig track for the actor with multiple skeletal mesh components, we add the control rig for the correct component because FControlRigParameter ...
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 ...
[CrashReport] Assertion failed: TaskDataArray.Num() == Exporter->VolumetricLightmapTaskGuids.Num()
UE - Graphics Features - Lumen - Oct 2, 2017This is a trending crash coming out of the 4.18 Previews. Users have not provided any descriptions of their actions when the crash occurred, but at least two of the affected projects are being creat ...
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 ...
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 ...
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 ...
Steam fails to initialize when using the steamclient file from SteamCMD
UE - Online - May 18, 2020Steam fails to initialize when using the steamclient file SteamCMDLogLoad: Game class is 'ShooterGame_FreeForAll' LogOnline: OSS: Creating online subsystem instance for: Steam LogOnline: Verbose: ...
Ongoing D3D 'HUNG' crash in FD3D11DynamicRHI::GetQueryData
UE - Graphics Features - Jan 18, 2017This is a new ticket for the D3D 'HUNG' crash originally reported in [Link Removed]. Some fixes were introduced in 4.14.2 that decreased the occurrences of this crash, but other cases are still ongo ...