Unreal Engine Issues
Unreal Engine Issues
Crash when using CastChecked<>(nullptr, ECastCheckedType::NullAllowed) in configurations where checks are disabled
UE - Core - Systems - Jun 19, 2025When using CastChecked<>(), the second parameter can be passed as ECastCheckedType::NullAllowed to make the check succeed when the input is nullptr. However, in UE 5.5 up to the latest engine versio ...
Instance Static Mesh element not rendered if array element is removed and another is added
UE - Gameplay - Dec 5, 2017Instance Static Mesh element is not rendered if array element is removed and another is added. The collision is still present and the instance count will still register as if the non-rendered elemen ...
Rotate about axis material node can cause Z-fighting in Niagara mesh particles
UE - Niagara - Oct 21, 2020The rotate about axis material node appears to cause z-fighting in mesh particles if they are scaled in the simulation. ...
Niagara: MeshParameterBinding property of the StaticMeshLocation module does not accept binding to parameters of type StaticMesh.
UE - Rendering - Architecture - Niagara - Jan 22, 2026On the details panel of the StaticMeshLocation module, when expanding the dropdown of the MeshParameterBinding property, user parameters of type StaticMesh don't show up (only those of type "Object" ...
Toggling ULevelStreaming::bShouldBeVisible causes replication errors
UE - Networking - Mar 17, 2017Looks like the replication system doesn't properly account for bShouldBeVisible. Once a level has be marked bShouldBeVisible=false on the server, the level is completely cleaned up and all actor cha ...
Component Array doesn't update properly when using Text Variables
Tools - Sep 19, 2018A Component Array doesn't update properly when using Structure Variables. Any array elements added after the setup don't get printed when the event is called. If you set the "Editable when Inherited ...
[Audio Capture] - Editor crashes when activating an Audio Capture component when there are no active input or output devices avilable
UE - Audio - Aug 12, 2022If a device has no available input or output devices, activating an Audio Capture component will cause the device to crash. Occurs in Editor and Runtime. Assertion failed: NumTotalFrames > 0 [File:E ...
Rendering from the Movie Render Queue at runtime while using the current level will fail, even when the levels match
zComponent - Archive - Jul 22, 2021When Use Current Level is true, the MRQ tries to validate that the maps are the same, but this will fail when the maps actually do match. The Use Current Level flag should allow the render to cont ...
When r.SSR.Stencil is enabled, there is wrong logic observed.
UE - Rendering - Features - Dec 19, 2025When 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 ...
Enum Variable doesn't pull the correct Default Value
UE - Gameplay - Blueprint - Aug 10, 2015Enum Variable doesn't pull/print the correct Default Value User Description: (Blueprint) User defined enum in 4.9 getting corrupted I believe there is a severe underlying issue in 4.9 regarding u ...