Push based fast array with net.PushModelSkipUndirtiedFastArrays not replicating across multiple PIE sessions

UE - Networking - Sep 19, 2022

The conditions for this bug are fairly specific. The actor must be statically placed, with its only replicated property being the fast array, and net.PushModelSkipUndirtiedFastArrays must be enabled ...

Client may receive failure message before ClientTravel RPC during non-seamless travel

UE - Networking - Aug 9, 2022

See linked UDN for more info. When a server initiates a non-seamless travel, it will inform any connected clients by sending the reliable ClientTravelInternal RPC. After a delay (controlled by Serve ...

Changes to AActor::SetReplicates caused Role/RemoteRole replication fix to regress

UE - Networking - Jul 14, 2022

There was a recent bug report that matched the description of some older cases (see linked UDN). The issue raised in those cases, [Link Removed], had been fixed, but the recent question seemed to in ...

Ensure hit in OutdatedKnownStaticMeshDetected for replicated StaticMeshComponent

UE - Networking - Jun 10, 2022

The component's KnownStaticMesh value is updated whenever UStaticMeshComponent::UpdateBounds is called, and AActor::OnRep_ReplicatedMovement can result in this being called for the component. If thi ...

Push based, COND_InitialOnly property can fail to be replicated when actor becomes relevant again

UE - Networking - Jun 9, 2022

COND_InitialOnly properties can be resent when an actor becomes relevant to a client again. However, if the property is push based and it was never replicated the first time the actor was created on ...

Replicated subobject won't be recorded in replay checkpoints if it has no replicated properties

UE - Networking - Jun 8, 2022

Because the subobject's RepLayout is empty, it won't write anything to the bunch when recording a replay checkpoint. This means that when scrubbing to a time past a checkpoint, the destroyed subobje ...

Pawn's role is incorrect in BeginPlay on client if a multicast RPC is called in BeginPlay on server

UE - Networking - Jun 6, 2022

It seems as though calling a multicast RPC during BeginPlay on the server will cause the new actor to finish spawning on the client before applying any initial replicated data, such as the actor's R ...

DemoNetDriver can cause ClearVoicePackets to be called multiple times in one tick

UE - Networking - May 18, 2022

Because DemoNetDriver doesn't override PostTickFlush, it will call the base UNetDriver's PostTickFlush. When both the game NetDriver and DemoNetDriver are ticked, this results in the online interfac ...

Client is unable to Server Travel with the host when Seamless Travel is disabled

UE - Networking - May 5, 2022

Client is unable to Server Travel with the host when Seamless Travel is disabled. Repro Rate: 3/3 Tested this in //UE4/Release-4.27 @ CL#18319896 and the client is able to join in, it is a regress ...

Replicated Child Actor in standalone editor instance causes package map errors

UE - Networking - Apr 25, 2022

This only seems to occur if the parent is statically placed, and only when launching the instances as standalone game from the editor. If the actor is dynamically spawned or if the instances are run ...