Networking
Multiplayer is a first-class concern rather than a later addition.
Transform replication. BPC_Replication interpolates towards the replicated transform with a
tolerance threshold and an adaptive sample rate — roughly 0.06 s while an object is moving, 0.5 s
when it is at rest — and replicates with SkipOwner so the player manipulating an object is not
corrected by their own data. Subclasses target either the whole actor
(BPC_Replication_Actor) or a tagged component (BPC_Replication_Component).
Server RPCs from non-pawns. Unreal normally only routes client-to-server RPCs from the player's
pawn. UAFPNetDriver overrides ShouldCallRemoteFunction and ProcessRemoteFunction so any object
implementing the marker interface IOutsidePawnRPCInterface may call server RPCs directly. This is
installed through AFS_Libraries/Config/Engine.ini, which replaces the default GameNetDriver.
BPC_State and BPC_Interaction_Select already rely on it. Multicast and client RPCs are
unaffected.
Replicated UI. URenderTargetReplicatorComponent JPEG-compresses a render target and multicasts
it. Together with BPC_ReplicatedUI and its "fake UI" registration, this is how one player sees
another player's interface.
