Unreal Engine Issues
Unreal Engine Issues
Scalar Parameter versus Constant placed in Alpha of LERP produces inconsistent results in Blendable
UE - Graphics Features - Jun 8, 2015When placing a Scalar Parameter into the Alpha position of a LERP you will not get the same results as placing a Constant Value when used in a Post Process Material. Constant Value of 0: [Image Rem ...
Procedural Mesh Component Blocks Level from Saving
UE - Gameplay - Components - Aug 29, 2016When a blueprint is added to a level that contains a procedural mesh component the level is unable to save. The error message that pops up is attached as a screenshot. Edit PatrickD (08-29-2016): C ...
Certain combined Linear/Angular movements cause Client to freeze for several seconds
UE - Simulation - Physics - May 24, 2019When using Replicated Movement, certain combined linear/angular movements cause the client to freeze for several seconds and then catch up to the server. This is a regression from 4.21.2 (CL-4753647 ...
RemoveAxisMapping() removes axis mappings of the same key regardless of Scale value
UE - Gameplay - Jun 26, 2019When you remove an axis mapping using a specific key it will remove all mappings even if they have separate scales. The user found a fix that I verified that worked. In "InputSettings.cpp", which i ...
Behavior of reparenting Component on UE5 is different from UE4
UE - Gameplay - Blueprint Editor - Mar 29, 2022In UE4, Reparenting the Child Component did not update it on the screen, but the Relative Transform was updated. However, UE5 now retains Relative Transform, so there are on-screen updates. This is ...
Virtual Heightfield Mesh crash using released Vertex Factory
UE - Rendering Architecture - Jul 25, 2023When using VirtualHeightfieldMesh we see intermittent crashes in FDepthPassMeshProcessor::TryAddMeshBatch(). This can happen when FVirtualTextureProducerCollection::CallPendingCallbacks() is called ...
Affect Indirect Lighting While Hidden can affect the environment after data layer unload in editor
UE - Graphics Features - Sep 9, 2024After setting Affects Indirect Lighting While Hidden but before saving the level, the emissive contribution persistents through datalayer visibility toggles. This does not appear to occur in PIE, on ...
LODs with screen size 0 in legacy assets are incorrectly converted to 1 on load
UE - Graphics Features - Sep 11, 2025When loading a mesh asset (static or skeletal) created in an old version of Unreal (e.g. 4.10), any LOD whose LOD screen size was originally set to 0, is converted to 1. This causes LODs that would ...
Mac Crashing on Editor Launch
UE - Graphics Features - Sep 24, 2015User reporting he is crashing when launching the Editor "This is a 4.9.1 binary build (latest), I can't give you the exact version because it crashes on the initialisation stage at 0%. The system i ...
Audio Components ignoring Start Time set by Play node on Android
UE - Audio - Jul 15, 2015Setting the start time within the Play node for an audio component does not function when deploying to Android. The set up works fine when playing on the PC, and the sound functions on the Android ...