Unreal Engine Issues
Unreal Engine Issues
Translucent Materials no longer reflect light when using Forward Lighting variable
UE - Graphics Features - Jun 7, 2016Translucent materials are no longer showing light reflections in scene when using r.forwardlighting 1 with lights. This is a regression from functionality in 4.11.2. This no longer works with 4.12 ...
Server RPC with struct param containing class reference does not pass parameter
UE - Networking - Apr 2, 2018Class ref is not passed to server within the struct in UE 4.19. Instead, the default value is passed to the server. LogNetPackageMap: Warning: SanityCheckExport: CacheObject == NULL. NetGUID: 1, Ob ...
Incorrect shading for SubSurface profile in the Blueprint Viewport.
UE - Graphics Features - Dec 30, 2016The Subsurface shading looks incorrect in the Blueprint Viewport window. Adjusting the cvar for r.sss.checkerboard from the default value of 2 to 1 looks more correct and a value of 0 switches back ...
Invalid Landscape Normals at component boundaries and subsections In Packaged Build
UE - Graphics Tools - Terrain - Oct 31, 2025In UE 5.6, heightmap texture compression was introduced. The original implementation did not consider duplicate pixels along subsection and shared textures (multi-component) boundaries. As a result, ...
Editor Crashes when importing some FBXs with multiple Material IDs in 4.14.2
UE - Editor - Content Pipeline - Import and Export - Jan 5, 2017This is a regression in behavior between 4.14.1 and 4.14.2! The editor will crash when importing FBX meshes that have multiple material ID assignments. If it's a single material ID it will import w ...
Random Number Generated in Constructor Returning Different Value on Begin Play
UE - Gameplay - Jan 13, 2016When generating a random number using FMath::RandHelper() in the constructor of an actor, attempting to print that same number on BeginPlay returns a different value than the constructor. However, ...
Particles Do Not Obey Lighting Channels
UE - Niagara - Apr 17, 2018Particle systems ignore lighting channels - no matter what channel a light is on (even if no channels are selected), it will affect lit particles. Changing lighting channels on the particle itself h ...
Crash with FBX with LODs when distance fields and Generated Lightmaps are enabled
UE - Graphics Features - Jan 12, 2015DESCRIPTION: When importing a mesh with 1 or more additional LODs when Generate Mesh Distance Fields has been enabled via the Project settings will cause a crash if the import options include using ...
Float Curve evaluation may yield completely wrong results due to floating-point precision issue
UE - Anim - Runtime - Oct 31, 2024Note: This is possibly related to [Link Removed]. For some inputs, function UE::Curves::WeightedEvalForTwoKeys() inside file "CurveEvaluation.cpp" can incorrectly return the value of the first key, ...
Blurry RVTs after camera jump
UE - Graphics Features - Aug 7, 2025When using Runtime Virtual Textures (RVT) on landscape in UE 5.5+, nearby tiles may remain blurry (low-resolution mips) after launching PIE or making large camera jumps (e.g. via bookmarks or viewpo ...