Unreal Engine Issues
Unreal Engine Issues
FNiagaraRendererMeshes::GetDynamicRayTracingInstances(...) corrupting GPUScene when rendering multiple views
UE - Rendering - Graphics Features - Ray Tracing - May 20, 2026When rendering a game in splitscreen using Lumen HWRT, Nanite and a large number of Niagara Mesh Particles 1mil+, various meshes and actors will stop rendering. Setting r.RayTracing.Geometry.Niagar ...
[Configuration] Exported Presentations do not adhere to "Visible Configuration" settings and display all Configurations
TM - Tools - May 19, 2026Reported in SF [Link Removed] Exported Presentations do not respect the "Visible Configuration" settings set for the Presentations and instead display all Configurations regardless of whether they ...
ApplyLocalExposure uses Output_ExtentInverse instead of Output_ViewportSizeInverse for bilateral grid UV
UE - Rendering - Graphics Features - May 18, 2026The ApplyLocalExposureCS shader in PostProcessLocalExposure.usf computes UV coordinates for the LumBilateralGrid 3D texture using Output_ExtentInverse (1/RenderTargetSize) instead of Output_Viewport ...
TObjectPtr property on struct can point to the archetype instead of the object
UE - Framework - Blueprint - May 18, 2026After creating the BP derived class and starting PIE, the problem pointer is set to the owning component as expected. However, after the component’s constructor, FObjectInitializer::InitProperties c ...
[Enhanced Input] Chord trigger fails when its referenced action lives in a lower-priority IMC
UE - Gameplay - Input - May 18, 2026Summary A UInputTriggerChordAction does not fire when the action it references (the "chording action") is mapped in a different Input Mapping Context with a lower priority than the IMC containing the ...
check(bRenderStateCreated) fires in SendRenderDynamicData_Concurrent called from FRegisterComponentContext::Process
UE - Rendering - Architecture - RHI - May 18, 2026FRegisterComponentContext::Process() in ActorComponent.cpp iterates over SendRenderDynamicDataPrimitives and calls SendRenderDynamicData_Concurrent() on each. The existing guard checks ::IsValid(Pri ...
Twinmotion sign-in error when attempting sign-in inside app
TM - Core - May 18, 2026Reported in SF [Link Removed] Attempting to sign into Twinmotion from within the TM 2026.1 editor results in a consistent sign-in error using the sign-in buttons. Initial sign-in during launch whe ...
Meshes with scaled root bones pop when entering simulation
UE - Runtime - Simulation - May 15, 2026This issue is fallout from the changes in 33851494. Prior to that, we didn’t get the pop on beginning the sim. The problem appears to be that in USkeletalMeshComponent::PerformBlendPhysicsBones we ...
iOS builds fail on Windows.
UE - Platform - Mobile - May 15, 2026Loading Windows installed iOs mobile provisioning profiles fails at start of iOS build from windows machine. This due to a recent change that attempts to load PKCS12 from mobileprovision files. Thes ...
Imported Substance materials behave incorrectly when applying UV rotation
TM - Tools - May 14, 2026Reported in SF [Link Removed] and on the forums at https://forums.unrealengine.com/t/substance-3d-materials-not-reflecting-light-properly/2718611 UV rotation behavior is incorrect for Substance mat ...