Unreal Engine Issues
Unreal Engine Issues
FMassMoveTargetFragment::CreateNewAction does not update PreviousAction, breaking the start-of-path avoidance fade and related behavior for MassEntity crowds
UE - Runtime - Character - Jul 28, 2026In MassEntity-based crowds, when an agent transitions from Stand to Move and begins walking, the Avoidance trait parameters StartOfPathDuration and StartOfPathAvoidanceScale, which are meant to temp ...
Background blur missing with HDR CompositeMode 1
UE - Rendering - Features - Jul 29, 2021UPD: According to Affects Version field, issue reproduces in 4.26, Regression for 4.27 - No. ...
Backout attempted fix for - AutoSize triggers ensure on shortened Skel Anim Section moved past anim length
zComponent - Archive - May 29, 2026In Sequencer, calling "Edit > Auto Size" on a UMovieSceneSkeletalAnimationSection triggers the LowerBound > UpperBound ensure in UMovieSceneSection::SetRange (MovieSceneSection.h:333) when the secti ...
Pasting timeline components into another actor and then choosing "cancel" on fix self context function references results in a broken state
UE - Framework - Components - Sep 13, 2021upd. Regression was checked on //UE4/Release-4.26 CL 15973114, issue was reproduced. Regression - No ...
Crash occurs in Hierarchical Instanced Static Mesh of Mesh with MinLOD set to 1 or higher
UE - Graphics Features - Oct 22, 2020I have attached a reproduction project with the above settings.[Link Removed] It crashes when packaged, launched and moved in-game. This issue seems to occur when there is an object in the Unbuilt ...
FViewElementPDI::DrawLine calls for SDPG_World are not rendered in PIE or in Game
UE - Rendering - RHI - Jan 7, 2026When View.Family->EngineShowFlags.CompositeEditorPrimitives is false in the function RenderEditorPrimitivesForDPG. This code picks which version of the batched lines to renderconst FBatchedElements ...
Making the viewport fullscreen while Application scale is a value other than 1.0 results in a zoomed in/out viewport
Tools - Jan 11, 2017When using Application Scale in the editor, using F11 to make the viewport fullscreen results in an either zoomed in or zoomed out fullscreen version. Note: This same issue occurs when using a comb ...
Fix PrimitiveComponent overlap indirection
UE - Simulation - Physics - Sep 27, 2016When doing overlap tests in PrimitiveComponent, UWorld->ComponentOverlapMulti is used. The callstack for that ends up looking like this (callstack is inverted, highest level on top): UWorld::Compo ...
Crash on setting Material in Element 1 of Combined Mesh
Tools - Mar 19, 2015Crash on clearing or setting the second or third material slot in the Static Mesh Editor on an imported combined FBX Mesh. Also Reproduced in Main Promotable-CL-2484152 (Perforce) NOTE: User is o ...
Regression: "Object Position" node in Light Function materials did not compile up to UE 5.0. Starting with 5.1, it compiles but outputs garbage values
UE - Rendering - Architecture - Materials - Aug 26, 2024Up to UE 5.0, when the "Object Position" node is used in the Material Editor as part of a material with Light Function domain, attempting to compile the material results in the following error: "[SM ...