Unreal Engine Issues
Unreal Engine Issues
FNiagaraScalabilityManager incorrectly reactivates a NiagaraComponent that was deactivated by runtime user code
UE - Niagara - Scalability - Oct 1, 2025Context: The Niagara System is the primary tool to do visual effects inside Unreal. Niagara systems can be culled due to distance. Problem: Once a deactivated Niagara System is culled due to distan ...
Shader Complexity View not working in Deferred Mobile Preview
UE - Platform - Mobile - Sep 30, 2025Proposed workaround:add in FMobileSceneRenderer::RenderDeferredMultiPass (MobileShadingRenderer.cpp): #if WITH_DEBUG_VIEW_MODES if (ViewFamily.UseDebugViewPS()) { return; } #endif // WITH_DEBU ...
BoxOverlapActors fails to catch an Overlaped actor with a particular scale, from a particular position
UE - Simulation - Core - Sep 30, 2025BoxOverlapActors fails to overlap a scaled Floor actor with a particular scale, from a particular position and extent. The setup is really specific and described in Steps to Reproduce. The required ...
Wrong density calculation in UBodySetup::CalculateMass
UE - Simulation - Core - Sep 29, 2025Wrong density calculation in UBodySetup::CalculateMass. The licensee has provided the following analysis and suggested fix: In UBodySetup::CalculateMass, the following code is present: // physical ...
Division by zero in FAnimNode_StrideWarping::EvaluateSkeletalControl_AnyThread
UE - Anim - Gameplay - Sep 29, 2025When an Actor's CustomTimeDilation is 0.0, functions FActorTickFunction::ExecuteTick() and FActorComponentTickFunction::ExecuteTickHelper() will call AActor::TickActor() and UActorComponent::TickCom ...
Custom Depth range is different than Pixel Depth range
UE - Rendering - Graphics Features - Sep 25, 2025Shaders that compare custom depth and pixel depth get wrong output values because the ranges are different. This error is most noticeable over large distances. The difference in ranges is due to t ...
NaN Present on IOS after UE5.6 Because of Removal of MobileSpecularGGX
UE - Platform - Mobile - Sep 24, 2025In UE5.6 MobileSpecularGGX was removed and now mobile devices also run D_GGX. The problem is that there are still cases where very bright values are produced (image 1) and thus NaNs appear in the Bl ...
FKeyHandle internal static atomic counter can overflow on long running games depending on usage pattern
UE - Anim - Sep 24, 2025Structure FKeyHandle stores an internal index, which is initialized from a static atomic counter in the default constructor: +----- FKeyHandle::FKeyHandle() { | static std::atomic<uint32> LastKey ...
Xcode 26/16.4 Metal Toolchain generates metallib's that are not compatible with iOS 16
UE - Platform - Apple - Sep 23, 2025Below is the error output from FirstPerson template as a C++ project: {+}../../../FirstPerson58CPP/Content/firstperson58cpp_sf_metal_es3_1_ios-metal_es3_1_ios.0.metallib, 5881486 bytes!2025-09-23 1 ...
Mutable constant texture variable with ClipUV mask only works with new experimental dynamic variable is connected as well
UE - Anim - Mutable - Sep 22, 2025We are attempting to use Mutable in 5.6.1 and have encountered an issue which we are not sure how to resolve. The issue occurs when using the ClipWithUVMask node. In short we have a customizable o ...