Unreal Engine Issues
Unreal Engine Issues
FViewElementPDI::DrawLine calls for SDPG_World are not rendered in PIE or in Game
UE - Rendering Architecture - RHI - Jan 7, 2026When View.Family->EngineShowFlags.CompositeEditorPrimitives is false in the function RenderEditorPrimitivesForDPG. This code picks which version of the batched lines to renderconst FBatchedElements ...
MultiProcessCook Shader Symbols fail to write when two workers race and try to write them at the same time
UE - Foundation - Data Pipeline - Cooker - Jan 4, 2026When shadersymbols are requested, cooking shaders writes the symbol files into {Project} /Saved/ShaderSymbols/<PlatformName>. These symbols are written by the function FShaderSymbolExport::Write ...
Virtual Memory leak when using specific rendering settings in the template project
UE - Rendering Architecture - RHI - Dec 20, 2025When a project is run with these settings in a template project, untracked virtual memory increases. Cvars r.GBufferFormat 3 r.Lumen.TraceMeshSDFs 1 r.Lumen.TranslucencyReflections.FrontLayer.Enab ...
Skeletal Mesh BLAS updates when not animating
UE - Rendering Architecture - RHI - Dec 19, 2025The BLAS for Skeletal Meshes that don't move, or tick get updated every frame even if the animation and skin cache aren't updated. This adds over 1ms to update time. The only exception is if the sk ...
Subobject ComponentClass overrides cause failing assertions due to UObject reconstruction on AsyncLoadingThread
UE - Framework - dSTM - Dec 19, 2025Context The blueprint editor allows you to override an actor component's class in derived blueprints (component details panel -> Component Class). [Image Removed] Problem When a blueprint and it ...
Reflections of Masked Materials incorrect with Lumen HWRT and Max Refraction Bounces > 0
UE - Graphics Features - Lumen - Dec 18, 2025Lumen HWRT Reflections of Masked Materials are incorrect when "r.Lumen.Reflections.HardwareRayTracing.Translucent.MaxRefractionBounces" is greater than 0. The same issue occurs if the Post-Process V ...
Editor localization causes the GetLinkedAnimLayerInstanceByGroup function to fail in retrieving the corresponding LinkedAnimLayer within the editor.
UE - Anim - Runtime - Anim Blueprints - Dec 18, 2025When using other language(such as Chinese) as editor language, the Group Name of the Animation Interface will be localized to Chinese. In editor, the animation blueprint grab the group from metadata ...
Cooker is asserting in Class.h on UE 5.7.1
UE - CoreTech - Dec 18, 2025From the linked EPS case: ---------------------------- In UE 5.7 there were some changes to how Enum member names are stored. This change introduces an assert when cooking using the Editor Debug e ...
Unable to interact or collide with geometry collection after Removal on Sleep or Break timer finishes, yet unbroken piece continue to render
UE - Simulation - Core - Dec 18, 2025Context: A static mesh is able to have a geometry collection generated from it using the Fracture editing mode. It can be fractured in many different ways, and when acted upon by a chaos field agent ...
If a child blueprint class has an Instanced/EditInlineNew object property, that property will always be detected as changed by the property editor (i.e. it will show a "Revert" arrow on that property), even if its properties are identical to the parent.
UE - Framework - Blueprint Editor - Dec 17, 2025Context: Blueprint classes can use Instanced/EditInlineNew object property specifiers to create and edit subobjects directly in the editor. Problem: If a child blueprint class has an Instanced/Edit ...