Virtual Memory leak when using specific rendering settings in the template project

UE - Rendering Architecture - Dec 20, 2025

When 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 - Graphics Features - Ray Tracing - Dec 19, 2025

The 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 ...

When r.SSR.Stencil is enabled, there is wrong logic observed.

UE - Graphics Features - Dec 19, 2025

When r.SSR.Stencil is enabled, the areas with high roughnesss are not discarded and Unlit materials are incorrectly handled. See the linked EPS case (Additional Info URL) for a full explanation of ...

Crash during .zfprj import when Feature detection quality is set to High and Use mosaic images as feature source is set to Yes

RS - Alignment - Dec 19, 2025

Found in 2.0.0.118621 (R200). It appears that the combination of Feature detection - High and Use mosaic images as feature source during .zfprj LiDAR import - Yes. causes a crash. Outcome: RS ...

Subobject ComponentClass overrides cause failing assertions due to UObject reconstruction on AsyncLoadingThread

UE - Framework - Blueprint - Dec 19, 2025

Context 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 ...

Call In Editor functions not working in blueprints

UE - Editor - Developer Usability - Dec 19, 2025

Context When selecting a component on an actor, any CallInEditor functions on the component's class appear as buttons in the details panel. Problem The CallInEditor functions don't execute in Blu ...

WorldToClip/ClipToWorld transform in materials not behaving as expected

UE - Graphics Features - Dec 19, 2025

In 5.3, the specified code will return all 0 or very small as expected. However in 5.4.4 and onwards (also checked in 5.6.1 & 5.7.1), it returns very large numbers. ...

Reflections of Masked Materials incorrect with Lumen HWRT and Max Refraction Bounces > 0

UE - Graphics Features - Lumen - Dec 18, 2025

Lumen 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 ...

Area scattering defaults to 0.01 spacing when input is invalid

TM - Tools - Dec 18, 2025

If the user provides an invalid input for Area spacing (for example, using the hotkey 'R' to check the raytraced image), the spacing defaults to a value of 0.01m. Depending on the size of the Area s ...

Substrate's coverage node does not skip unlit emissive part which have no coverage

UE - Graphics Features - Substrate - Dec 18, 2025

Substrate's coverage node doesn't seem to cull masked pixels of unlit emissive slabs. This is an important optimization when using masked unlit particles. When using a lit slab, the instructions for ...