Compilation error when using Particle SubUV in Niagara Mesh Particles with Raytracing enabled.

UE - Niagara - Oct 12, 2021

The licensee has shared the following workaround for modifying NiagaraMeshVertexFactory.ush. struct FVertexFactoryInterpolantsVSToPS { TANGENTTOWORLD_INTERPOLATOR_BLOCK #if USE_PARTICLE_SUBU ...

Crash after 'Reparent Blueprint' when renaming component on-top of orphaned inherited component

UE - Framework - Blueprint Editor - May 7, 2024

After reparenting a blueprint and inherited components from the previous parent are removed, trying to give a new component the same name as a previous component causes a crash inside UObject::Renam ...

When PCH is Disabled, Error Occurs in VulkanGenericPlatform.h at Android Build

UE - Graphics Features - Dec 6, 2018

If disable PCH in Target.cs, an error will occur when building for Android. The log is as follows. LogPlayLevel: Error: D:/Build/Release-4_21_0/Engine/Source/Runtime/VulkanRHI/Private/Android/../Vu ...

UAbilitySystemComponent's CurrentMontageStop() function does not use OverrideBlendOutTime Float Parameter.

UE - Gameplay - Jul 2, 2019

In the attached example, the third person mannequin character's BeginPlay() runs an Ability_Task which starts an animation montage. In the task it is specified that the blend out time (BlendOutTime ...

Blueprint processing is heavy in PIE since 4.26

UE - Gameplay - Blueprint - Feb 17, 2021

As the attached image shows, there is no problem in 4.25.4, and the process is noticeably slower in 4.26.1. Also, there is no problem in Standalone. The problem occurs only in PIE. ...

Connecting GetSequenceBinding node to LevelSequence including Spawnable Actor etc. will result in error

UE - Gameplay - Blueprint Editor - Feb 22, 2018

[Link Removed] ・Open attached project ・Open NewMap ・Confirm that an error appears on the console ・When creating a Windows (64-Bit) package in this state, the same error occurs ...

Blueprint Launches onto tvOS fail during runstep: Error_DeviceOSNewerThanSDK

UE - Platform - Mobile - Apr 19, 2019

When a user launches blueprint project to a tvOS device they will fail to run the project during the run step and if they manually try to launch the app from the dashboard. This issue does not repr ...

NPC - Does not get updates from Material Parameter Collection changes in the editor

UE - Niagara - Sep 30, 2024

When 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 ...

Assets on paths with speed parameters are sped up in Path Tracer exports

TM - Rendering - Jul 18, 2025

Reported in SF [Link Removed] In Path Tracer renders, all paths with a speed component (vehicles, bicycles, custom) will render at an increased speed than specified in the exported render. This is ...

Static/stationary child actor components are invisible and/or move position when placed inside a dynamically loaded level

UE - Framework - Components - Oct 31, 2024

When loading a non-world partitioned level into a persistent world partitioned level, parent actors with child actor components within the loaded map will move position or become invisible. Within t ...