Unreal Engine Issues
Unreal Engine Issues
FFT bloom disappears for some kernel/viewport size combinations (survey grid sized for R instead of 2R)
UE - Rendering - Features - Oct 22, 2026FFT bloom (convolution bloom) renders nothing for some combinations of kernel size, r.Bloom.ScreenPercentage and viewport sizes (e.g. 50% and 1024 x 768)Root cause PostProcessFFTBloom.cpp computes ...
Substrate Adaptive GBuffer: HWRT Hit Lighting drops indirect lighting from lights with a Light Function (GI / Reflections)
UE - Rendering - Features - Shading Models - Oct 22, 2026The Light Function variant of the hit lighting miss shader is compiled as the Light Function material, so MATERIAL_IS_SUBSTRATE=1. This makes it read the ray hit surface from the payload incorrectly ...
[PCG Mode] Tool actors spawned by PCG Editor Mode tools ignore the current level and are always created in the PersistentLevel
UE - Graphics Tools - PCG - Procedural Tools - Oct 21, 2026Summary In a non-World-Partition map with streamed sublevels, PCG Editor Mode interactive tools (Draw Spline / SpacingTool, Area, Paint, Volume, ...) spawn their new tool actor in the PersistentLevel ...
[5.8] Cherry-pick CL 55798320: re-precache PSOs in ULandscapeComponent and UGroomComponent OnRegister (fixes bPSOPrecacheCalled ensure on re-register)
UE - Rendering - RHI - Oct 21, 2026In 5.8, UPrimitiveComponent::OnUnregister resets FPSOPrecacheComponentData, which clears bPSOPrecacheCalled (regression from CL 48140040). ULandscapeComponent and UGroomComponent only call PrecacheP ...
[UE 5.8][MediaViewer] Crash when switching Level Editor viewport type to Cinematic Viewport
UE - CAPT - Tools - Media Viewer - Oct 19, 2026POST LINK: https://forums.unrealengine.com/t/ue-5-8-mediaviewer-crash-when-switching-level-editor-viewport-type-to-cinematic-viewport/2747407 POST BODY:Summary The editor crashes when Media Viewer ...
Sequencer.AllowPausedClock makes Audio/Platform-clock sequences evaluate at a negative time after any earlier game pause
UE - ACT Character - Sequencer - Oct 17, 20265.8 added Sequencer.AllowPausedClock (on by default) in FMovieSceneTimeController_ExternalClock::OnRequestCurrentTime (MovieSceneTimeController.cpp): PausedTime = Context.World()>RealTimeSeconds - ...
Sequencer: Entity task Pre/Post callbacks are skipped despite ForcePrePostTask when a required component is absent
UE - ACT Character - Sequencer - Oct 13, 2026Tasks scheduled through the entity task builder with FTaskParams::ForcePrePostTask() are documented to run their PreTask and PostTask callbacks even when there is no work for the task body. This gua ...
Deadlock in URigHierarchy
UE - ACT Character - Control Rig - Oct 12, 2026We are regularly hitting a deadlock on 5.8.3. We have one background worker evaluating an animation, holding the RigHierarchy's ElementsLock and waiting for the global GC lock And one Background w ...
Sequencer custom task scheduler hangs with more than 512 tasks (TDynamicSparseBitSet::IsBitSet and operator|=)
UE - ACT Character - Sequencer - Oct 12, 2026With Sequencer.CustomTaskScheduling enabled, a task graph with more than 512 tasks can hang FEntitySystemScheduler::ExecuteTasks. Reported by a licensee, they hit it with a 528 task graph under Clan ...
UBA: crash related to BeyongTrust PGHook.dll and Detour for local jobs.
UE - Core - Cpp Tools - UnrealBuildAccelerator - Oct 9, 2026A license provided a log containing a UBA crash related to PGHook injecting itself when ISPC runs. ...