Unreal Engine Issues
Unreal Engine Issues
Post Process Animation Blueprint Crash When Using Blend Node
UE - Anim - Runtime - Anim Blueprints - Sep 24, 2025When using a Blend node inside a Post Process Animation Blueprint, the editor crashes while rendering thumbnails. The crash occurs because USkeletonThumbnailRenderer attempts to draw a thumbnail wit ...
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 ...
In 5.6, bWarningsAsErrors does not work with clang
UE - Foundation - Cpp Tools - UnrealBuildTool - Sep 20, 2025In 5.6, many warnings and errors specify their command line arguments to the compiler with these new C# attributes: [WarningsClangToolChain(["-Wno-date-time"], ["-Wdate-time", "-Wno-error=date-ti ...
Ray tracing scene doesn't reflect WPO with instance custom data
UE - Graphics Features - Ray Tracing - Sep 19, 2025When custom instance data is used to calculate WPO in a Material and applied to an ISM the WPO value in the Lumen scene (ray tracing scene) is different than the visible scene resulting in incorrect ...
Seam visible when using a material with BumpOffset on a Nanite mesh
UE - Graphics Features - Nanite - Sep 18, 2025When a material that uses BumpOffset is fed into the Emissive Color of Surface Opaque Default Lit material and then applied to a nanite mesh, a visible seam can be seen along edges and the intersect ...
Setting a struct bool property (bitfield) to itself writes the wrong value
UE - Framework - Blueprint Compiler - Sep 17, 2025There's an issue when assigning a bitfield bool to a native bool in Blueprints. Currently, the engine erroneously treats the memory for a local bool as a uint8 bitfield, which is undefined behavior. ...
Nanite Skeletal Meshes Invalidate VSM
UE - Graphics Features - Nanite - Sep 17, 2025Nanite Skeletal Meshes will always invalidate VSMs, even with their Shadow Cache Invalidation Behavior set to Rigid. This does not match the behavior of non-Nanite Skeletal Meshes. ...
Controller::OnPossessedPawnChanged broadcasts (Pawn->null) but not (null->Pawn) during AGameModeBase::RestartPlayer()
UE - Gameplay - Sep 17, 2025Context AController has a blueprint assignable delegate that fires when the possessed pawn changes. This should fire in both singleplayer and networked games. The bug is reproducible in single play ...
Hovering items at bottom right of Content Browser does not display tooltip and causes cursor flicker
UE - Editor - Applied Usability - Sep 17, 2025When hovering over items located at the bottom right corner of the Content Browser while the Editor is maximized, the tooltip is not displayed. It seems that the tooltip would extend beyond the edge ...
Painted foliage in a level instance can be selected in Foliage mode if the level instance is in main level, and foliage is duplicated if moved.
UE - World Creation - Worldbuilding Tools - Foliage - Sep 16, 2025Context Foliage Mode is a set of tools that enables you to quickly paint or erase sets of Static Meshes or Actor Foliage. Level Instancing is a level-based workflow designed to improve and streamlin ...