Reference to control rig can be lost on actors with multiple skeletal mesh components

UE - Anim - Rigging - Control Rig - Apr 4, 2023

In 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 - Foundation - Core - Jul 30, 2020

The 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, 2017

This 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, 2021

From 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 ...

Filling Vertex Colors does not propogate down to other LODs

Tools - Nov 19, 2018

The original reported behavior called out that filling individual channels did not apply to LODs when LOD Model Painting = False. With changes implemented in 4627582, the initial fill will reach LOD ...

Render target size mistmatch in ShaderDrawDebug

UE - Graphics Features - Jun 9, 2020

We 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 ...

Unwanted black boundaries are displayed in a vertical split-screen with 3 players.

UE - Gameplay - Dec 2, 2019

Floating point error from UGameViewportClient::SplitscreenInfo causes this issue. FMath::TruncToInt( 3240 /*ViewportSize*/ * 0.333f/*Ratio in SplitScreenInfo*/ ) = 1079 I suggested a following t ...

Templated enum GetValueAsString function returns incorrectly formatted string

UE - Foundation - Core - Aug 19, 2020

For many years there has been a static function on UEnum called GetValueAsString which would convert an enum like EAttachmentRule::KeepWorld to the string "KeepWorld", if you passed in the explicit ...

Project configured to spawn Niagara system via Character blueprint in a Code project fails to Cook, then crashes project on open

UE - Niagara - Mar 7, 2019

Project configured to spawn Niagara system via Character blueprint in a Code project fails to Cook, then crashes project on open Discovered when verifying [Link Removed] (also similar to [Link Remo ...

Ongoing D3D 'HUNG' crash in FD3D11DynamicRHI::GetQueryData

UE - Graphics Features - Jan 18, 2017

This 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 ...