Unreal Engine Issues
Unreal Engine Issues
FMath::Eval ignores groupings while solving
UE - Core - Systems - Nov 8, 2022This is not a regression. Tested in //UE5/Release-5.0 CL20979098 FMath::Eval ignores groupings while solving problems. This has caused some confusion with users who are expecting the groupings to b ...
Material Layers Ignore Virtual Texture Sampler Restrictions
UE - Rendering - Architecture - Mar 25, 2024Virtual Textures can be assigned to Texture Sample Parameters that are not configured for Virtual Textures, if that parameter is inside of a Material Layer. Also found in Release-5.4, CL 32426910 ...
WasRecentlyRendered() and GetLastRenderTimeOnScreen() still triggers when a skeletal mesh re-enters the view frustum despite being occluded.
UE - Rendering - Architecture - Dec 4, 2024AActor::WasRecentlyRendered() and UPrimitiveComponent::GetLastRenderTimeOnScreen() both still trigger when a skeletal mesh (occluded behind a wall) re-enters the player's view frustum after being ou ...
Duplicating SkeletalMesh in packaged game causes crash
UE - Rendering - Features - Nanite - Mar 11, 2025This code worked until UE5.4. NaniteResource added in 5.5 causes this issue. ...
When a Niagara User Parameter is renamed, mesh bindings on Niagara Mesh Renderers are not updated, and the binding is silently broken
UE - Rendering - Architecture - Niagara - Mar 13, 2025In Niagara, Mesh Renderers expose a "Meshes" array for selecting the meshes to be rendered. On each array entry, a property "Mesh Parameter Binding" is available and allows the user to override that ...
Find in Blueprints: Default values of TMap keys are not returned
UE - Framework - Blueprint Editor - Sep 3, 2025Context Find-in-Blueprints can be used to search the current, or all, blueprints. If you enter a simple string, it would return nodes, pins, pin default values and default values for BP Variables ( ...
FBX Import - Morph target normals not correctly applied when imported as LOD 0
UE - Editor - Open File Formats - FBX - Nov 27, 2025This is a regression since 5.5 with skeletal meshes where morph target normal/tangent deformation only works when a mesh is imported as a LOD of an existing skeletal mesh, but not when imported as L ...
Mutable compile hangs indefinitely when using Customizable Object Extension Data Constants
UE - Runtime - Mutable - Oct 25, 2025I am getting a CO compile to hang indefinitely while compiling. It seems to be caused by the optimization in LocalLogicOptimiserAST that tries to convert 3+ conditionals into a switch statement. It ...
Occlusion Queries for Static Meshes with ERuntimeVirtualTextureMainPassType::Exclusive
UE - Rendering - Architecture - Feb 20, 2026Static Meshes that draw into RVTs and have "Draw In Main Pass" is set to "From Virtual Texture" (ERuntimeVirtualTextureMainPassType::Exclusive) will still draw in Occlusion Queries. This can be tr ...
Input pins of BP node are not updated after a hot reload
UE - Gameplay - Blueprint - Apr 17, 2015If a code defined function that takes in a parameter is called from blueprints, the BP node will show the input pin for the parameter. If the parameter list is changed after the node is created and ...