Unreal Engine Issues

USceneComponent::AttachChildren entries overwritten on Client with NULL

The issue occurs if a non-replicated actor is attached to a replicated scene component on the client, and then the same is done on the same scene component on the server. The attached actor does not ...

Calling TearOff then Destroy on an actor results in client actor also being destroyed

When calling TearOff followed immediately by Destroy, the channel will be closed with the reason that the actor was destroyed, so the actor will be destroyed on the client as well. In the UDN linke ...

Ensure in APlayerState::OnRep_bIsInactive may be hit

The ensure in APlayerState::OnRep_bIsInactive may be hit due to the player state being replicated before the game state. The check is necessary for making sure the game state is available, but the e ...

Duplicate level collections not being respected by UGameEngine::NetworkRemapPath

When NetworkRemapPath was refactored in 4.26 to support replay connections via the rep graph, the check for duplicate level id on the driver was lost in the new code path. This causes the demo driv ...

Attaching scene component with "SnapToTarget" overrides relative transform on client

If received in the same update on a client, a replicated attach with attachment rule "SnapToTarget" will overwrite any replicated changes to the relative transform. Additionally, once a scene compon ...

Network profiler can report sent RPCs despite a null ViewTarget preventing the send

Due to the hard-coded 1.5 second timeout for clients in UNetDriver:if ( OwningActor != NULL && Connection->State == USOCK_Open && ( Connection->Driver->GetElapsedTime() - Connection->LastReceiveTime ...

Child Actor component doesn't properly destroyed on clients.

BroadcastNetworkFailure called twice when outdated client network failure is received

When a pending net game on a client receives a NMT_Upgrade control message, a network failure of type OutdatedClient is broadcast. Then during TickWorldTravel when the client tries to return to the ...

"Assertion failed: NumberOfFreeBits >= 0" on clients that attempt to connect to a server with the -NoPacketHandler option

With the rework of IP address resolution in 4.25, this assert now occurs. When no packet handler is used, UPendingNetGame::InitNetDriver calls SendInitialJoin() immediately, before async address res ...

Available network bandwidth is too low for uncapped but slow frame rates

The networking system has a max frame rate of 120hz by default. Inside UNetConnection::Tick it computes an estimated bandwidth by using that max frame rate, the engine's max frame rate, and the actu ...