Unreal Engine Issues
Unreal Engine Issues
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 ...
Fbx importer can import valid under 30Hz anim at 30Hz
Tools - Jul 17, 2017The samplerate of a track was compute with the following formula Equation 1: number of Key / animation Time This formula work only if we have animation keys that are time equidistant. example of ...
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 ...
Kinematic in Physics Asset Overrides Bone Scale of Skeletal Meshes
UE - Simulation - Physics - Oct 7, 2020In a character's Physics Asset, a bone that is set to Kinematic and its children will have a scale of 1 overriding the Skeletal Mesh's Scale Transform settings. When the root of the body is changed ...
Rendered panoramas using Lumen may be overexposed
TM - Rendering - Sep 30, 2025Reported in SF [Link Removed] Lumen Panorama renders in 2025.2 may appear overexposed compared to the viewport, or when comparing the same render produced in 2025.1.1 This only appears to occur wi ...
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 ...
The Left Mouse Button Pressed event is not firing when Input Mode Game Only is set and Show Mouse Cursor is true
UE - Editor - UI Systems - Slate - Sep 20, 2019The Left Mouse Button Pressed event is not firing when Input Mode Game Only is set and Show Mouse Cursor is true. Attached is an example project (4.23) that demonstrates the issue. Found in 4.23.0 ...
OnHit not firing when capsule collider passes onto very close and same height mesh
UE - Simulation - Physics - Sep 10, 2019When a capsule collider passes from the top of one piece of geometry to another that is very close the OnHit event doesn't fire. I have attached a project that demonstrates the issue in 4.23. A vid ...
Merging negative-scaled actors breaks materials
UE - World Creation - Worldbuilding Tools - HLOD - Mar 27, 2018Materials are broken when merging a mesh with another that has negative scale Licencee states that bisMirrored in FMeshMergeHelpers::TransformRawMeshVertexData seems to be involved. Does not occur ...
FBX Export - StaticMesh export to FBX crashes if UVElements has more channels than VertexInstanceUVs
zComponent - Archive - Jan 22, 2026As indicated in the repro steps, we have a StaticMesh asset that, for some reason, has a mismatch in their serialized bulk data where:MeshDescription->GetNumUVElementChannels() == 2FStaticMeshConstA ...