Unreal Engine Issues
Unreal Engine Issues
Lumen Global Distance Field Trace Leaking due to Surface Cache Sampling
UE - Rendering - Graphics Features - Jan 12, 2026At specific distances from a thin wall, surfaces inside of a sealed chamber can receive indirect lighting from outside, leaking light into the chamber. This appears to be due to how SWRT handles sa ...
Play Media Player Node Causes Blueprint Functions to be Uncallable
UE - Gameplay - Blueprint - Feb 23, 2016This only occurs in standalone or a packaged game Having a Play Media Player node in a blueprint causes all of that blueprint's functions to become uncallable. Found in 4.11 Preview 5. Reproduced ...
Invalid GUIDs on new material instance parameters cause overrides to break on base param rename
UE - Rendering - Architecture - Materials - Sep 3, 2025When a parameter value is assigned on a newly created material instance (constant or dynamic) using Set***ParameterValueInternal, the parameter’s ExpressionGUID is left invalid (0,0,0,0). Parameter ...
Blueprint with instance static mesh from construction script will cause crash when using the build then build geometry
Tools - Mar 12, 2015When using a BP with component instance static mesh that is added via the construction script, when using the build button in the toolbar to build lighitng and geometry everything will work correctl ...
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 ...
Mover | FStanceModifier adjustment teleport on Crouch/Uncrouch can fail when child components intersect world
UE - Gameplay - Player Movement - Mover - Feb 3, 2026Context When crouching and uncrouching with Mover’s DefaultMovementSet, the pawn capsule’s half height is changed. This behavior mimics the CharacterMovementComponent. To ensure the pawn’s feet sta ...
Unable to save project due to user created blueprint node that creates user created object
UE - Gameplay - Blueprint - Apr 28, 2015When a user creates a blueprint node of their own that is used to spawn a user created object, the project becomes unable to be saved after the blueprint is put into use. ...
NPC - Does not get updates from Material Parameter Collection changes in the editor
UE - Niagara - Sep 30, 2024When an MPC is selected as the Source Material Collection for an NPC, all of its current parameters are carried over to the NPC with their current values. After that, if parameters are added to, rem ...
Damping is handled differently at lower frame rates
UE - Gameplay - Aug 3, 2016Damping is handled differently at lower frame rates. Slight changes in damping at lower FPS (25) drastically effects objects and isn't applied in the same way as at higher FPS (60) User Description ...
Blueprint derived from C++ class not saving correctly
UE - Gameplay - Blueprint - Jul 27, 2015The blueprint that the user is using loses some data when the editor closes and reopens despite saving all of the content. Note: Currently unsure of what exactly causes this but as I am able to rep ...