Building Lighting will Generate Additional Lightmaps after Rotating Lightsource

UE - Graphics Features - Jul 7, 2015

Lightmap sizes seem inconsistent after rotating a light source and rebuilding the lighting. This causes concern about file sizes when packaging the project that is using baked static lighting. The ...

When using 'r.VT.SplitPhysicalPoolSize 64' with nanite meshes, mesh painting does not update in real time (only updates after stroke finished), duplicates mesh painting across separate instances of a mesh, and sometimes doesn't show up in PIE.

UE - Rendering Architecture - Mar 3, 2025

When using Mesh Painting on nanite meshes in 5.5 with 'r.VT.SplitPhysicalPoolSize' set to non-zero values (e.g. 16, 64), several issues occur, such as: 1. Painting doesn't update in real time (only ...

Surface Profile Skin shading has some unexpected stripe rendering issues

UE - Graphics Features - Apr 3, 2018

So it looks like the artifact is definitely related to whether sss checkboard is enabled, but I can't reproduce it if enabling checkboard right after open the map, I mean it has to be reproduced aft ...

In 5.6, bWarningsAsErrors does not work with clang

UE - Foundation - Cpp Tools - UnrealBuildTool - Sep 20, 2025

In 5.6, many warnings and errors specify their command line arguments to the compiler with these new C# attributes:    [WarningsClangToolChain(["-Wno-date-time"], ["-Wdate-time", "-Wno-error=date-ti ...

Android: Mali Txxx GPUs Encounter Stretching Geometry When Running with Support GPU Scene Enabled

UE - Platform - Mobile - Nov 27, 2019

When attempting to run SunTemple with r.Mobile.SupportGPUScene enabled on some Mali GPUs, the project renders with what looks like pieces of the geometry stretching across the level and bending out ...

Selecting a Packed Level Actor Blueprint Asset in Viewport does not select all packed assets

UE - World Creation - Worldbuilding Tools - Level Instances - Nov 16, 2022

The Packed Level Actor behavior has changed since 5.0.3, exhibiting the behavior described in the Result. I was able to reproduce this 4/4 times on Windows. When testing on 5.0.3, I confirmed that t ...

ScreenPosition material node outputs upside down ViewportUV when launching on android

UE - Graphics Features - Aug 28, 2018

ScreenPosition UV upside down on mobile. From User: "I believe the editor mobile preview provides "correct" results, while the mobile device produces upside down results. I ran into this issue w ...

Direct Capsule Shadows with Point Lights also project shadow on opposite side and direction

UE - Graphics Features - Dec 14, 2016

When using a Direct Capsule Shadows on a skeletal mesh with a Stationary Point light, depending on the point lights placement, light source radius, and nearby surfaces will cast the shadow on the op ...

When welding a procedural mesh component to a non-physics simulated static mesh that overlap they collide continuously

UE - Simulation - Physics - Jul 18, 2019

When attaching a Procedural Mesh Component with a copied static mesh to a static mesh component the two meshes collide and "push" each other (go flying on play). Weld is to be used for simulated ph ...

[CrashReport] UE4Editor_Landscape!FLandscapeSplinesSceneProxy::GetDynamicMeshElements() [landscapesplines.cpp:159]

UE - LD & Modeling - Terrain - Landscape - Nov 17, 2017

This is an infrequent crash in 4.18. Users have not provided any descriptions of their actions when the crash occurred. Source Context 147 for (int32 ViewIndex = 0; ViewIndex < Views.Num( ...