Color shifting occurs from screen probe gather ping-pong when Lumen active

UE - Rendering - Features - Lumen - Apr 29, 2024

A subtle yellow tint color shift occurs when Lumen is active due to usage of R11G11B10_Float targets, mostly from r.Lumen.ScreenProbeGather.SpatialFilterProbes where we ping-pong between R11G11B10_F ...

Make warning about using collision and 'components space' in RigidBody node more visible

UE - Simulation - Physics - Feb 1, 2017

In the RigidBody anim node, if the user enables collision while Component Space Simulation is enabled, there will be warnings in the output log saying:Warning Trying to use world collision with comp ...

When importing multiple meshes at once and change the Uniform Scale meshes import at different sizes

UE - Editor - Content Pipeline - Import and Export - Sep 21, 2017

When a large quantity (about 50 in this case) are imported simultaneously, and the Import Uniform Scale is changed to any other number besides 1, random meshes differ in size. This happens regardles ...

GPU Lightmass ignores IES Profiles on Static Lights while building lighting

UE - Rendering - Features - Jun 8, 2022

This is a regression tested in //UE4/Release-4.27 CL#18319896 GPU Lightmass ignores IES Profiles on Static Lights while building lighting. Tested with different Global Illumination and Reflection s ...

Runtime Virtual Texture rendering can allocate more FRDGBuffers than expected

UE - Rendering - Architecture - Dec 10, 2024

When rendering runtime virtual texture pages without throttling (when r.VT.MaxUploadsPerFrame is high or during Movie RenderQueue captures) the number of FRDGBuffers allocated by the Render Graph Bu ...

[CrashReport] UE4Editor_CoreUObject!FUObjectArray::AllocateSerialNumber() [uobjectarray.cpp:307]

UE - Editor - Content Pipeline - Import and Export - Sep 20, 2017

This is a somewhat common crash in 4.17. Users have not provided any descriptions of their actions when the crash occurred. Source Context 304 int32 FUObjectArray::AllocateSerialNumber(in ...

Enum with "MAX" element at other than the last element removes user defined last element

UE - Foundation - Core - Oct 18, 2019

FNativeClassHeaderGenerator::ExportEnum produces this behavior. If an enum has “MAX” somewhere in the array, it removes last element. I tested my code to fix the issue.// code placeholder bool UE ...

Montage Editor: Mouse Wheel Cannot Scroll to the Bottom of notify section when there are many track.

UE - Runtime - Animation - Jul 21, 2025

When a large number of notify tracks are added in the Montage Editor, the mouse wheel scroll does not allow the user to reach the bottom-most tracks. Only by manually dragging the scrollbar can the ...

Cloth paint update issues

UE - Simulation - Physics - Jan 7, 2020

Activating and Deactivating Cloth Paint marks the skeletal mesh as dirty, even if no values were painted and there is no transaction in the Undo History. Painting Max Distance values from non-zero ...

Mover plugin: Crash on UFloorQueryUtils::ComputeFloorDist() and other utility functions that assume the pawn uses a UCapsuleComponent

UE - Runtime - Character - Dec 4, 2025

The following functions have been found to perform unchecked casts of the pawn's "UpdatedComponent" to class UCapsuleComponent, possibly resulting in crashes:UFloorQueryUtils::ComputeFloorDist()UGro ...