Crash when recombining Value Pin after swapping Target Wild Card pin from a Vector2D to a Vector on a Set By-Ref Var node

UE - Gameplay - Blueprint - Jul 18, 2022

This is not a regression. Tested in //UE4/Release-4.27 CL18319896 Crash when recombining Value Pin after swapping Target Wild Card pin from a Vector2D to a Vector on a Set By-Ref Var node.  ...

ISM Component in an instanced BP does not take into account changes to NumCustomDataFloats from the BP class

UE - Graphics Features - Sep 16, 2022

PerInstanceSMCustomData 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, 2023

The 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, 2024

When 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 ...

Point light leaking throught thin geometry

UE - Graphics Features - Oct 29, 2024

In 4.27, ray traced point lights can leak through thin meshes. This bug does not exist in Unreal Engine 5, due to many of the potential rendering areas being fundamentally changed. ...

Performance hitch from RemoveGeometryCache flushing the render thread

UE - Editor - Content Pipeline - Alembic - Jun 12, 2025

FGeometryCacheStreamingManager::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 ...

FFieldPath resolution doesn't handle redirection

UE - CoreTech - Feb 16, 2022

A 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 ...

4.6 Delegate error in Blueprints

UE - Gameplay - Blueprint - Dec 12, 2014

When looking into the bd_hud_scoring and bd_rules_maze blueprints in the users project (Provided below), there are nodes that are throwing errors. If you press compile, the errors go away and the co ...

Level sequence updates more than once per frame when content editors are open

UE - Anim - Sequencer - May 27, 2016

When content editors are open, they cause sequencer to be updated more than once per frame. This causes animations running in PIE to play faster than expected. Licensee provides code for a potential ...

Blueprint Implementable Events and Event dispatchers with the same name break the event dispatcher.

UE - Gameplay - Blueprint - Sep 22, 2015

Creating an event dispatcher and BlueprintImplementableEvent function with the same names causes a signature conflict inside the blueprint. The event dispatcher is then broken as it cannot be delet ...