// Copyright 1998-2018 Epic Games, Inc. All Rights Reserved.


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Replication Graph

Implementation of Replication Driver. This is customizable via subclassing UReplicationGraph. Default implementation (UReplicationGraph) does not fully function and is intended to be overridden.
	Check out BasicReplicationGraph.h for a minimal implementation that works "out of the box" with a minimal feature set.
	Check out ShooterGame / UShooterReplicationGraph for a more advanced implementation.



High level overview of ReplicationGraph:
	* The graph is a collection of nodes which produce replication lists for each network connection. The graph essentially maintains persistent lists of actors to replicate and feeds them to connections.

	* This allows for more work to be shared and greatly improves the scalability of the system with respect to number of actors * number of connections.

	* For example, one node on the graph is the spatialization node. All actors that essentially use distance based relevancy will go here. There are also always relevant nodes. Nodes can be global, per connection, or shared (E.g, "Always relevant for team" nodes).

	* The main impact here is that virtual functions like IsNetRelevantFor and GetNetPriority are not used by the replication graph. Several properties are also not used or are slightly different in use.

	* Instead there are essentially three ways for game code to affect this part of replication:
		* The graph itself. Adding new UReplicationNodes or changing the way an actor is placed in the graph.
		* FGlobalActorReplicationInfo: The associative data the replication graph keeps, globally, about each actor.
		* FConnectionReplicationActorInfo: The associative data that the replication keeps, per connection, about each actor.

	* After returned from the graph, the actor lists are further culled for distance and frequency, then merged and prioritized. The end result is a sorted list of actors to replicate that we then do logic for creating or updating actor channels.