Unreal Engine Issues
Unreal Engine Issues
Pressing the "Show Inactive" button in the material instance editor did not display groups that did not contain the active parameter
UE - Rendering Architecture - Materials - Aug 1, 2024When pressing the "Show Inactive" button in the material instance editor, all material parameters are supposed to be displayed in the EditorUI. This is not the case, only some of the parameters are ...
Specular lighting occurs that ignores occlusion when lighting a Subsurface material from behind
UE - Graphics Features - Dec 19, 2023Incremental GC vs Loading Screens deadlock
UE - CoreTech - Sep 5, 2024A licensee is reporting that using a loading screen with the incremental garbage collector can result in a dead lock when a loading screen is displayed. The licensee found out that: -------------- ...
Material Emissive Color not working with SkyAtmosphereIlluminance Material Expression
UE - Graphics Features - Jan 9, 2025A licensee has reported that they are unable to use an emissive material utilizing the SkyAtmosphereLightIlluminance material expression together with Nanite and Lumen. The linked UDN has some more ...
Virtual Bone caused nanite skinned mesh crash
UE - Graphics Features - Nanite - May 31, 2025When a Nanite skeletal mesh has a virtual bone the engine can crash when changing LODs ...
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 ...
Significant hitch occurs when invoking ApplySettings on a UGameUserSettings object
UE - Graphics Features - Jun 18, 2025Calling the ApplySettings method on a UGameUserSettings object results in a noticeable hitch, with severity proportional to the number of primitive components present in the scene. This hitch stems ...
When exporting static meshes with bExportSourceMesh enabled, there is a problem where all UVs are fragmented.
UE - Editor - Content Pipeline - Import and Export - Sep 22, 2025From customer: "In the StaticMesh Export option, when bExportSourceMesh is set to True, exporting StaticMesh Assets and importing them into DDC tools such as 3dsMax or Maya results in the UVs being ...
If 'Enable Physics Interaction' is disabled, the player can still interact with physics objects
UE - Gameplay - Oct 22, 2015If 'Enable Physics Interaction' is disabled, the player can still interact with physics objects User Description: I have a Bus Vehicle with custom physics (skeletal mesh). So I can walk through th ...
Game sounds only play during first PIE editor session for Linux project
UE - Platform - Linux - May 11, 2015Games sounds will play as appropriate during first PIE session but subsequent PIE sessions have no sound until editor is closed / reopened. ...