Unreal Engine Issues
Unreal Engine Issues
Rendered panoramas using Lumen may be overexposed
TM - Rendering - Sep 30, 2025Reported in SF [Link Removed] Lumen Panorama renders in 2025.2 may appear overexposed compared to the viewport, or when comparing the same render produced in 2025.1.1 This only appears to occur wi ...
Translucent Materials no longer reflect light when using Forward Lighting variable
UE - Graphics Features - Jun 7, 2016Translucent materials are no longer showing light reflections in scene when using r.forwardlighting 1 with lights. This is a regression from functionality in 4.11.2. This no longer works with 4.12 ...
StaticMesh export to FBX crashes if UVElements has more channels than VertexInstanceUVs
UE - Editor - Content Pipeline - FBX - Jan 22, 2026As indicated in the repro steps, we have a StaticMesh asset that, for some reason, has a mismatch in their serialized bulk data where:MeshDescription->GetNumUVElementChannels() == 2FStaticMeshConstA ...
Server doesn't process anim notifies with montage tick type set to queued when bad network conditions occur
UE - Anim - Gameplay - May 3, 2023After some testing this issue looks to only occur with queued notifies and not with branching point notifies. UDN: https://udn.unrealengine.com/s/question/0D54z00009643x4CAA/server-doesnt-process-a ...
RenderTarget Texture Alpha rendered incorrectly when SceneCapture2D AA set to true
UE - Graphics Features - Jan 8, 2016The Alpha Channel of the Render Target Texture is rendered as a value of 1 (solid white) when the SceneCapture2D actor is set to LDR with PP and Anti-Aliasing is set to true in the General Show Flag ...
Modulated shadows do not render in the correct area on older devices / versions of Android OS
UE - Platform - Mobile - Apr 5, 2016This issue was reported by a user who was having issues with their modulated shadows showing up in random spots on their mobile devices. Their devices were a Samsung Galaxy Note 2 and a ASUS Zenfon ...
Crash with FBX with LODs when distance fields and Generated Lightmaps are enabled
UE - Graphics Features - Jan 12, 2015DESCRIPTION: When importing a mesh with 1 or more additional LODs when Generate Mesh Distance Fields has been enabled via the Project settings will cause a crash if the import options include using ...
Crash trying to convert skeletal mesh to Nanite
UE - Rendering - Graphics Features - Nanite - Mar 6, 2025In SkeletalRenderNanite.cpp / FDynamicSkelMeshObjectDataNanite::UpdateBonesRemovedByLOD, bone indices are of type FBoneIndexType (defined as uint16 from BoneIndices.h), instead of int32. On line 18 ...
Insufficient precision of Decode71 function
UE - Rendering - Architecture - Shaders - Jun 5, 2025Encode71 and Decode71 in DeferredShadingCommon.ush are functions that convert 8-bit values to 7-bit values and mask values, and licensees have reported that the accuracy is insufficient when usi ...
Does FSlateElementBatcher::AddCachedElements need to check if r.HDR.UI.CompositeMode is enabled?
UE - Editor - UI Systems - Aug 28, 2024When a specific configuration of HDR cvars are set, PIE in a New Editor Window will not render the game world. Settings (For DefaultEngine.ini): ```[SystemSettings] r.AllowHDR=1 r.HDR.Display.Color ...