Unreal Engine Issues

InstancedStaticMesh displaying corrupt lightmap data

I think I narrowed this issue down to bad UV coordinates being interpreted during the BasePassVertexShader execution applied to instancing. At this line in VertexFactoryGetInterpolantsVSToPS: flo ...

iOS/TVos/Mac Compilation Error - Argument List Too Long

Compilations are failing on iOS, tvOS and Mac due to the following clang error: clang: error: unable to exectute command: posix_spawn failed: Argument list too long ...

Multiplayer Preview in VR HMD input routed to all players

Multiplayer Preview in VR is not useful because HMD input is routed to all players. ...

Parameterized Vector4 is treated as Float3

A Parameterized Vector4 are being treated as Float3. This prevents users from being able to use Vector4s in an If node during runtime. This is seen as far back as //UE4/Release4.22 cl 8065155 so th ...

Current animation asset is lost in animation preview when a post process anim BP is compiled

UDebugSkelMeshComponent and PreviewInstance are lost current animation asset. There are 2 ways to fix below void UDebugSkelMeshComponent::InitAnim(bool bForceReinit) { // If we already have Pre ...

Lightmaps not carrying over with 'Save Current As'

I can reproduce it, other developers reported to me too.  Not a problem in 4.22 ...

VFInitRotation(Cascade) always provides the same rotation

This problem caused by incorrect initialization of RandomStream in the GPU particle. //PaticleGpuSimulation.cpp virtual void Init() override { ... check(AllocatedTiles.Num() == TileTimeOfDe ...

Particles can flicker at the end of first emitter loop when interpolated spawning is enabled

Particles flicker at the end of first emitter loop when interpolated spawning is enabled This issue does not occur if interpolated spawning is disabled. This issue does not occur for any of the su ...

SSGI is glitchy with splitscreen multiplayer

UProceduralMeshComponent::UpdateMeshSection does not call UProceduralMeshComponent::UpdateCollision

Updating a procedural mesh results in an incomplete collision update. Collision bounds appear to get updated properly, but collision data is not updated, despite a navigation rebuild being triggered ...