Unreal Engine Issues
Unreal Engine Issues
Montage Root Motion does not work from sub anim instances
UE - Anim - Gameplay - Oct 25, 2019Root motion from sub instances is not used when the parent instance is marked as 'Root Motion from Montages Only'. Proposed fix is to modify USkeletalMeshComponent::IsPlayingNetworkedRootMotionMo ...
ISM Component in an instanced BP does not take into account changes to NumCustomDataFloats from the BP class
UE - Graphics Features - Sep 16, 2022PerInstanceSMCustomData is bulk serialized and doesn't get changed on the BP instance when changing NumCustomDataFloats, possibly causing out of bounds array access leading to a crash. Possible sol ...
FMaterialResource::IsDualBlendingEnabled bug
UE - Rendering Architecture - Materials - Jul 24, 2023The user has a proposed fix for this in the case. FMaterialResource::IsDualBlendingEnabled needs the following modification that includes MaterialInstance check: bool bMaterialRequestsDualSourceBle ...
Auto Exposure Compensation Curve issue when switching from Histogram to Manual
UE - Rendering Architecture - Feb 21, 2024When switching the Camera's Exposure Metering Mode from Histogram to Manual, there is a single-frame flash. The Licensee has a proposed code change that would fix this issue. Also found in 5.4, CL 3 ...
Lumen interior light leaking occurs with realistic sun Lux values (20k)
UE - Graphics Features - Lumen - Aug 23, 2024When a realistic sun Lux value of 20,000 for the sun directional light, interior light leaking is much more pronounced then when using the default directional light Lux value of 10 Lux. ...
Performance hitch from RemoveGeometryCache flushing the render thread
UE - Editor - Content Pipeline - Alembic - Jun 12, 2025FGeometryCacheStreamingManager::RemoveGeometryCache calls FlushRenderingCommands which shows up as a hitch when profiling. [Link Removed] Ideally the flush added in CL#23782411 to fix a rare deadl ...
Framerate drops when using SceneCaptureComponents with a RenderTarget in VR
UE - Platform - XR - May 14, 2018Using SceneCapture in packaged VR projects causes poor performance. Also observed with SceneCaptureCube Does not occur in 4.18 ...
Attempting to apply instance changes to blueprint after altering a struct array crashes editor
UE - Gameplay - Blueprint - Dec 14, 2015Editor crashes if a struct array that has been made editable is edited in an instance within the details pane of the level viewport, then the changes are applied from the instance to the base bluepr ...
FFieldPath resolution doesn't handle redirection
UE - CoreTech - Feb 16, 2022A licensee has found that redirectors don't apply to FFieldPath. We should integrate it with the following changes:It needs better error handling (looks like it could infinitely recurse),The change ...
Crash When Curve Editor is on When Animating Button Transform in Widget Blueprint
UE - Editor - UI Systems - Mar 18, 2016In a Widget Blueprint, after animating a button to transform vertically (possibly other directions) with the Curve Editor active, engine will crash upon creating a second animation. ...