Merge pull request #17227 from Faless/multiplayer_api

[RFC] MultiplayerAPI refactor

4 files changed, 85 insertions, 672 deletions

diff --git a/scene/main/node.cpp b/scene/main/node.cpp
index 2c4708b37f..ec01490ae5 100644
--- a/scene/main/node.cpp
+++ b/scene/main/node.cpp
@@ -477,7 +477,7 @@ bool Node::is_network_master() const {
 
 	ERR_FAIL_COND_V(!is_inside_tree(), false);
 
-	return get_tree()->get_network_unique_id() == data.network_master;
+	return get_multiplayer_api()->get_network_unique_id() == data.network_master;
 }
 
 /***** RPC CONFIG ********/
@@ -667,200 +667,16 @@ Variant Node::_rpc_unreliable_id_bind(const Variant **p_args, int p_argcount, Va
 }
 
 void Node::rpcp(int p_peer_id, bool p_unreliable, const StringName &p_method, const Variant **p_arg, int p_argcount) {
-
 	ERR_FAIL_COND(!is_inside_tree());
-
-	bool skip_rpc = false;
-	bool call_local_native = false;
-	bool call_local_script = false;
-
-	if (p_peer_id == 0 || p_peer_id == get_tree()->get_network_unique_id() || (p_peer_id < 0 && p_peer_id != -get_tree()->get_network_unique_id())) {
-		//check that send mode can use local call
-
-		Map<StringName, RPCMode>::Element *E = data.rpc_methods.find(p_method);
-		if (E) {
-
-			switch (E->get()) {
-
-				case RPC_MODE_DISABLED: {
-					//do nothing
-				} break;
-				case RPC_MODE_REMOTE: {
-					//do nothing also, no need to call local
-				} break;
-				case RPC_MODE_SYNC: {
-					//call it, sync always results in call
-					call_local_native = true;
-				} break;
-				case RPC_MODE_MASTER: {
-					call_local_native = is_network_master();
-					if (call_local_native) {
-						skip_rpc = true; //no other master so..
-					}
-				} break;
-				case RPC_MODE_SLAVE: {
-					call_local_native = !is_network_master();
-				} break;
-			}
-		}
-
-		if (call_local_native) {
-			// done below
-		} else if (get_script_instance()) {
-			//attempt with script
-			ScriptInstance::RPCMode rpc_mode = get_script_instance()->get_rpc_mode(p_method);
-
-			switch (rpc_mode) {
-
-				case ScriptInstance::RPC_MODE_DISABLED: {
-					//do nothing
-				} break;
-				case ScriptInstance::RPC_MODE_REMOTE: {
-					//do nothing also, no need to call local
-				} break;
-				case ScriptInstance::RPC_MODE_SYNC: {
-					//call it, sync always results in call
-					call_local_script = true;
-				} break;
-				case ScriptInstance::RPC_MODE_MASTER: {
-					call_local_script = is_network_master();
-					if (call_local_script) {
-						skip_rpc = true; //no other master so..
-					}
-				} break;
-				case ScriptInstance::RPC_MODE_SLAVE: {
-					call_local_script = !is_network_master();
-				} break;
-			}
-		}
-	}
-
-	if (!skip_rpc) {
-		get_tree()->_rpc(this, p_peer_id, p_unreliable, false, p_method, p_arg, p_argcount);
-	}
-
-	if (call_local_native) {
-		Variant::CallError ce;
-		call(p_method, p_arg, p_argcount, ce);
-		if (ce.error != Variant::CallError::CALL_OK) {
-			String error = Variant::get_call_error_text(this, p_method, p_arg, p_argcount, ce);
-			error = "rpc() aborted in local call:  - " + error;
-			ERR_PRINTS(error);
-			return;
-		}
-	}
-
-	if (call_local_script) {
-		Variant::CallError ce;
-		ce.error = Variant::CallError::CALL_OK;
-		get_script_instance()->call(p_method, p_arg, p_argcount, ce);
-		if (ce.error != Variant::CallError::CALL_OK) {
-			String error = Variant::get_call_error_text(this, p_method, p_arg, p_argcount, ce);
-			error = "rpc() aborted in script local call:  - " + error;
-			ERR_PRINTS(error);
-			return;
-		}
-	}
+	get_multiplayer_api()->rpcp(this, p_peer_id, p_unreliable, p_method, p_arg, p_argcount);
 }
 
-/******** RSET *********/
-
 void Node::rsetp(int p_peer_id, bool p_unreliable, const StringName &p_property, const Variant &p_value) {
-
 	ERR_FAIL_COND(!is_inside_tree());
-
-	bool skip_rset = false;
-
-	if (p_peer_id == 0 || p_peer_id == get_tree()->get_network_unique_id() || (p_peer_id < 0 && p_peer_id != -get_tree()->get_network_unique_id())) {
-		//check that send mode can use local call
-
-		bool set_local = false;
-
-		Map<StringName, RPCMode>::Element *E = data.rpc_properties.find(p_property);
-		if (E) {
-
-			switch (E->get()) {
-
-				case RPC_MODE_DISABLED: {
-					//do nothing
-				} break;
-				case RPC_MODE_REMOTE: {
-					//do nothing also, no need to call local
-				} break;
-				case RPC_MODE_SYNC: {
-					//call it, sync always results in call
-					set_local = true;
-				} break;
-				case RPC_MODE_MASTER: {
-					set_local = is_network_master();
-					if (set_local) {
-						skip_rset = true;
-					}
-
-				} break;
-				case RPC_MODE_SLAVE: {
-					set_local = !is_network_master();
-				} break;
-			}
-		}
-
-		if (set_local) {
-			bool valid;
-			set(p_property, p_value, &valid);
-
-			if (!valid) {
-				String error = "rset() aborted in local set, property not found:  - " + String(p_property);
-				ERR_PRINTS(error);
-				return;
-			}
-		} else if (get_script_instance()) {
-			//attempt with script
-			ScriptInstance::RPCMode rpc_mode = get_script_instance()->get_rset_mode(p_property);
-
-			switch (rpc_mode) {
-
-				case ScriptInstance::RPC_MODE_DISABLED: {
-					//do nothing
-				} break;
-				case ScriptInstance::RPC_MODE_REMOTE: {
-					//do nothing also, no need to call local
-				} break;
-				case ScriptInstance::RPC_MODE_SYNC: {
-					//call it, sync always results in call
-					set_local = true;
-				} break;
-				case ScriptInstance::RPC_MODE_MASTER: {
-					set_local = is_network_master();
-					if (set_local) {
-						skip_rset = true;
-					}
-				} break;
-				case ScriptInstance::RPC_MODE_SLAVE: {
-					set_local = !is_network_master();
-				} break;
-			}
-
-			if (set_local) {
-
-				bool valid = get_script_instance()->set(p_property, p_value);
-
-				if (!valid) {
-					String error = "rset() aborted in local script set, property not found:  - " + String(p_property);
-					ERR_PRINTS(error);
-					return;
-				}
-			}
-		}
-	}
-
-	if (skip_rset)
-		return;
-
-	const Variant *vptr = &p_value;
-
-	get_tree()->_rpc(this, p_peer_id, p_unreliable, true, p_property, &vptr, 1);
+	get_multiplayer_api()->rsetp(this, p_peer_id, p_unreliable, p_property, p_value);
 }
 
+/******** RSET *********/
 void Node::rset(const StringName &p_property, const Variant &p_value) {
 
 	rsetp(0, false, p_property, p_value);
@@ -882,6 +698,30 @@ void Node::rset_unreliable_id(int p_peer_id, const StringName &p_property, const
 }
 
 //////////// end of rpc
+Ref<MultiplayerAPI> Node::get_multiplayer_api() const {
+	if (multiplayer_api.is_valid())
+		return multiplayer_api;
+	if (!is_inside_tree())
+		return Ref<MultiplayerAPI>();
+	return get_tree()->get_multiplayer_api();
+}
+
+Ref<MultiplayerAPI> Node::get_custom_multiplayer_api() const {
+	return multiplayer_api;
+}
+
+void Node::set_custom_multiplayer_api(Ref<MultiplayerAPI> p_multiplayer_api) {
+
+	multiplayer_api = p_multiplayer_api;
+}
+
+const Map<StringName, Node::RPCMode>::Element *Node::get_node_rpc_mode(const StringName &p_method) {
+	return data.rpc_methods.find(p_method);
+}
+
+const Map<StringName, Node::RPCMode>::Element *Node::get_node_rset_mode(const StringName &p_property) {
+	return data.rpc_properties.find(p_property);
+}
 
 bool Node::can_call_rpc(const StringName &p_method, int p_from) const {
 
@@ -2877,6 +2717,9 @@ void Node::_bind_methods() {
 
 	ClassDB::bind_method(D_METHOD("is_network_master"), &Node::is_network_master);
 
+	ClassDB::bind_method(D_METHOD("get_multiplayer_api"), &Node::get_multiplayer_api);
+	ClassDB::bind_method(D_METHOD("get_custom_multiplayer_api"), &Node::get_custom_multiplayer_api);
+	ClassDB::bind_method(D_METHOD("set_custom_multiplayer_api", "api"), &Node::set_custom_multiplayer_api);
 	ClassDB::bind_method(D_METHOD("rpc_config", "method", "mode"), &Node::rpc_config);
 	ClassDB::bind_method(D_METHOD("rset_config", "property", "mode"), &Node::rset_config);
 
@@ -2958,6 +2801,8 @@ void Node::_bind_methods() {
 	ADD_PROPERTYNZ(PropertyInfo(Variant::STRING, "name", PROPERTY_HINT_NONE, "", 0), "set_name", "get_name");
 	ADD_PROPERTYNZ(PropertyInfo(Variant::STRING, "filename", PROPERTY_HINT_NONE, "", 0), "set_filename", "get_filename");
 	ADD_PROPERTYNZ(PropertyInfo(Variant::OBJECT, "owner", PROPERTY_HINT_RESOURCE_TYPE, "Node", 0), "set_owner", "get_owner");
+	ADD_PROPERTYNZ(PropertyInfo(Variant::OBJECT, "multiplayer_api", PROPERTY_HINT_RESOURCE_TYPE, "MultiplayerAPI", 0), "", "get_multiplayer_api");
+	ADD_PROPERTYNZ(PropertyInfo(Variant::OBJECT, "custom_multiplayer_api", PROPERTY_HINT_RESOURCE_TYPE, "MultiplayerAPI", 0), "set_custom_multiplayer_api", "get_custom_multiplayer_api");
 
 	BIND_VMETHOD(MethodInfo("_process", PropertyInfo(Variant::REAL, "delta")));
 	BIND_VMETHOD(MethodInfo("_physics_process", PropertyInfo(Variant::REAL, "delta")));
diff --git a/scene/main/node.h b/scene/main/node.h
index 341869f7ba..2e8716cbd1 100644
--- a/scene/main/node.h
+++ b/scene/main/node.h
@@ -151,6 +151,8 @@ private:
 		NAME_CASING_SNAKE_CASE
 	};
 
+	Ref<MultiplayerAPI> multiplayer_api;
+
 	void _print_tree(const Node *p_node);
 
 	Node *_get_node(const NodePath &p_path) const;
@@ -403,15 +405,20 @@ public:
 	void rpc_id(int p_peer_id, const StringName &p_method, VARIANT_ARG_LIST); //rpc call, honors RPCMode
 	void rpc_unreliable_id(int p_peer_id, const StringName &p_method, VARIANT_ARG_LIST); //rpc call, honors RPCMode
 
-	void rpcp(int p_peer_id, bool p_unreliable, const StringName &p_method, const Variant **p_arg, int p_argcount);
-
 	void rset(const StringName &p_property, const Variant &p_value); //remote set call, honors RPCMode
 	void rset_unreliable(const StringName &p_property, const Variant &p_value); //remote set call, honors RPCMode
 	void rset_id(int p_peer_id, const StringName &p_property, const Variant &p_value); //remote set call, honors RPCMode
 	void rset_unreliable_id(int p_peer_id, const StringName &p_property, const Variant &p_value); //remote set call, honors RPCMode
 
+	void rpcp(int p_peer_id, bool p_unreliable, const StringName &p_method, const Variant **p_arg, int p_argcount);
 	void rsetp(int p_peer_id, bool p_unreliable, const StringName &p_property, const Variant &p_value);
 
+	Ref<MultiplayerAPI> get_multiplayer_api() const;
+	Ref<MultiplayerAPI> get_custom_multiplayer_api() const;
+	void set_custom_multiplayer_api(Ref<MultiplayerAPI> p_multiplayer_api);
+	const Map<StringName, RPCMode>::Element *get_node_rpc_mode(const StringName &p_method);
+	const Map<StringName, RPCMode>::Element *get_node_rset_mode(const StringName &p_property);
+
 	bool can_call_rpc(const StringName &p_method, int p_from) const;
 	bool can_call_rset(const StringName &p_property, int p_from) const;
 
diff --git a/scene/main/scene_tree.cpp b/scene/main/scene_tree.cpp
index 037331dec1..4419dfe70f 100644
--- a/scene/main/scene_tree.cpp
+++ b/scene/main/scene_tree.cpp
@@ -484,7 +484,7 @@ bool SceneTree::idle(float p_time) {
 
 	idle_process_time = p_time;
 
-	_network_poll();
+	multiplayer_api->poll();
 
 	emit_signal("idle_frame");
 
@@ -1633,16 +1633,11 @@ Ref<SceneTreeTimer> SceneTree::create_timer(float p_delay_sec, bool p_process_pa
 
 void SceneTree::_network_peer_connected(int p_id) {
 
-	connected_peers.insert(p_id);
-	path_get_cache.insert(p_id, PathGetCache());
-
 	emit_signal("network_peer_connected", p_id);
 }
 
 void SceneTree::_network_peer_disconnected(int p_id) {
 
-	connected_peers.erase(p_id);
-	path_get_cache.erase(p_id); //I no longer need your cache, sorry
 	emit_signal("network_peer_disconnected", p_id);
 }
 
@@ -1661,471 +1656,70 @@ void SceneTree::_server_disconnected() {
 	emit_signal("server_disconnected");
 }
 
-void SceneTree::set_network_peer(const Ref<NetworkedMultiplayerPeer> &p_network_peer) {
-	if (network_peer.is_valid()) {
-		network_peer->disconnect("peer_connected", this, "_network_peer_connected");
-		network_peer->disconnect("peer_disconnected", this, "_network_peer_disconnected");
-		network_peer->disconnect("connection_succeeded", this, "_connected_to_server");
-		network_peer->disconnect("connection_failed", this, "_connection_failed");
-		network_peer->disconnect("server_disconnected", this, "_server_disconnected");
-		connected_peers.clear();
-		path_get_cache.clear();
-		path_send_cache.clear();
-		last_send_cache_id = 1;
+Ref<MultiplayerAPI> SceneTree::get_multiplayer_api() const {
+	return multiplayer_api;
+}
+
+void SceneTree::set_multiplayer_api(Ref<MultiplayerAPI> p_multiplayer_api) {
+	ERR_FAIL_COND(!p_multiplayer_api.is_valid());
+
+	if (multiplayer_api.is_valid()) {
+		multiplayer_api->disconnect("network_peer_connected", this, "_network_peer_connected");
+		multiplayer_api->disconnect("network_peer_disconnected", this, "_network_peer_disconnected");
+		multiplayer_api->disconnect("connected_to_server", this, "_connected_to_server");
+		multiplayer_api->disconnect("connection_failed", this, "_connection_failed");
+		multiplayer_api->disconnect("server_disconnected", this, "_server_disconnected");
 	}
 
-	ERR_EXPLAIN("Supplied NetworkedNetworkPeer must be connecting or connected.");
-	ERR_FAIL_COND(p_network_peer.is_valid() && p_network_peer->get_connection_status() == NetworkedMultiplayerPeer::CONNECTION_DISCONNECTED);
+	multiplayer_api = p_multiplayer_api;
+	multiplayer_api->set_root_node(root);
 
-	network_peer = p_network_peer;
+	multiplayer_api->connect("network_peer_connected", this, "_network_peer_connected");
+	multiplayer_api->connect("network_peer_disconnected", this, "_network_peer_disconnected");
+	multiplayer_api->connect("connected_to_server", this, "_connected_to_server");
+	multiplayer_api->connect("connection_failed", this, "_connection_failed");
+	multiplayer_api->connect("server_disconnected", this, "_server_disconnected");
+}
 
-	if (network_peer.is_valid()) {
-		network_peer->connect("peer_connected", this, "_network_peer_connected");
-		network_peer->connect("peer_disconnected", this, "_network_peer_disconnected");
-		network_peer->connect("connection_succeeded", this, "_connected_to_server");
-		network_peer->connect("connection_failed", this, "_connection_failed");
-		network_peer->connect("server_disconnected", this, "_server_disconnected");
-	}
+void SceneTree::set_network_peer(const Ref<NetworkedMultiplayerPeer> &p_network_peer) {
+
+	multiplayer_api->set_network_peer(p_network_peer);
 }
 
 Ref<NetworkedMultiplayerPeer> SceneTree::get_network_peer() const {
 
-	return network_peer;
+	return multiplayer_api->get_network_peer();
 }
 
 bool SceneTree::is_network_server() const {
 
-	ERR_FAIL_COND_V(!network_peer.is_valid(), false);
-	return network_peer->is_server();
+	return multiplayer_api->is_network_server();
 }
 
 bool SceneTree::has_network_peer() const {
-	return network_peer.is_valid();
+	return multiplayer_api->has_network_peer();
 }
 
 int SceneTree::get_network_unique_id() const {
 
-	ERR_FAIL_COND_V(!network_peer.is_valid(), 0);
-	return network_peer->get_unique_id();
+	return multiplayer_api->get_network_unique_id();
 }
 
 Vector<int> SceneTree::get_network_connected_peers() const {
-	ERR_FAIL_COND_V(!network_peer.is_valid(), Vector<int>());
-
-	Vector<int> ret;
-	for (Set<int>::Element *E = connected_peers.front(); E; E = E->next()) {
-		ret.push_back(E->get());
-	}
 
-	return ret;
+	return multiplayer_api->get_network_connected_peers();
 }
 
 int SceneTree::get_rpc_sender_id() const {
-	return rpc_sender_id;
+	return multiplayer_api->get_rpc_sender_id();
 }
 
 void SceneTree::set_refuse_new_network_connections(bool p_refuse) {
-	ERR_FAIL_COND(!network_peer.is_valid());
-	network_peer->set_refuse_new_connections(p_refuse);
+	multiplayer_api->set_refuse_new_network_connections(p_refuse);
 }
 
 bool SceneTree::is_refusing_new_network_connections() const {
-
-	ERR_FAIL_COND_V(!network_peer.is_valid(), false);
-
-	return network_peer->is_refusing_new_connections();
-}
-
-void SceneTree::_rpc(Node *p_from, int p_to, bool p_unreliable, bool p_set, const StringName &p_name, const Variant **p_arg, int p_argcount) {
-
-	if (network_peer.is_null()) {
-		ERR_EXPLAIN("Attempt to remote call/set when networking is not active in SceneTree.");
-		ERR_FAIL();
-	}
-
-	if (network_peer->get_connection_status() == NetworkedMultiplayerPeer::CONNECTION_CONNECTING) {
-		ERR_EXPLAIN("Attempt to remote call/set when networking is not connected yet in SceneTree.");
-		ERR_FAIL();
-	}
-
-	if (network_peer->get_connection_status() == NetworkedMultiplayerPeer::CONNECTION_DISCONNECTED) {
-		ERR_EXPLAIN("Attempt to remote call/set when networking is disconnected.");
-		ERR_FAIL();
-	}
-
-	if (p_argcount > 255) {
-		ERR_EXPLAIN("Too many arguments >255.");
-		ERR_FAIL();
-	}
-
-	if (p_to != 0 && !connected_peers.has(ABS(p_to))) {
-		if (p_to == get_network_unique_id()) {
-			ERR_EXPLAIN("Attempt to remote call/set yourself! unique ID: " + itos(get_network_unique_id()));
-		} else {
-			ERR_EXPLAIN("Attempt to remote call unexisting ID: " + itos(p_to));
-		}
-
-		ERR_FAIL();
-	}
-
-	NodePath from_path = p_from->get_path();
-	ERR_FAIL_COND(from_path.is_empty());
-
-	//see if the path is cached
-	PathSentCache *psc = path_send_cache.getptr(from_path);
-	if (!psc) {
-		//path is not cached, create
-		path_send_cache[from_path] = PathSentCache();
-		psc = path_send_cache.getptr(from_path);
-		psc->id = last_send_cache_id++;
-	}
-
-	//create base packet, lots of hardcode because it must be tight
-
-	int ofs = 0;
-
-#define MAKE_ROOM(m_amount) \
-	if (packet_cache.size() < m_amount) packet_cache.resize(m_amount);
-
-	//encode type
-	MAKE_ROOM(1);
-	packet_cache[0] = p_set ? NETWORK_COMMAND_REMOTE_SET : NETWORK_COMMAND_REMOTE_CALL;
-	ofs += 1;
-
-	//encode ID
-	MAKE_ROOM(ofs + 4);
-	encode_uint32(psc->id, &packet_cache[ofs]);
-	ofs += 4;
-
-	//encode function name
-	CharString name = String(p_name).utf8();
-	int len = encode_cstring(name.get_data(), NULL);
-	MAKE_ROOM(ofs + len);
-	encode_cstring(name.get_data(), &packet_cache[ofs]);
-	ofs += len;
-
-	if (p_set) {
-		//set argument
-		Error err = encode_variant(*p_arg[0], NULL, len);
-		ERR_FAIL_COND(err != OK);
-		MAKE_ROOM(ofs + len);
-		encode_variant(*p_arg[0], &packet_cache[ofs], len);
-		ofs += len;
-
-	} else {
-		//call arguments
-		MAKE_ROOM(ofs + 1);
-		packet_cache[ofs] = p_argcount;
-		ofs += 1;
-		for (int i = 0; i < p_argcount; i++) {
-			Error err = encode_variant(*p_arg[i], NULL, len);
-			ERR_FAIL_COND(err != OK);
-			MAKE_ROOM(ofs + len);
-			encode_variant(*p_arg[i], &packet_cache[ofs], len);
-			ofs += len;
-		}
-	}
-
-	//see if all peers have cached path (is so, call can be fast)
-	bool has_all_peers = true;
-
-	List<int> peers_to_add; //if one is missing, take note to add it
-
-	for (Set<int>::Element *E = connected_peers.front(); E; E = E->next()) {
-
-		if (p_to < 0 && E->get() == -p_to)
-			continue; //continue, excluded
-
-		if (p_to > 0 && E->get() != p_to)
-			continue; //continue, not for this peer
-
-		Map<int, bool>::Element *F = psc->confirmed_peers.find(E->get());
-
-		if (!F || F->get() == false) {
-			//path was not cached, or was cached but is unconfirmed
-			if (!F) {
-				//not cached at all, take note
-				peers_to_add.push_back(E->get());
-			}
-
-			has_all_peers = false;
-		}
-	}
-
-	//those that need to be added, send a message for this
-
-	for (List<int>::Element *E = peers_to_add.front(); E; E = E->next()) {
-
-		//encode function name
-		CharString pname = String(from_path).utf8();
-		int len = encode_cstring(pname.get_data(), NULL);
-
-		Vector<uint8_t> packet;
-
-		packet.resize(1 + 4 + len);
-		packet[0] = NETWORK_COMMAND_SIMPLIFY_PATH;
-		encode_uint32(psc->id, &packet[1]);
-		encode_cstring(pname.get_data(), &packet[5]);
-
-		network_peer->set_target_peer(E->get()); //to all of you
-		network_peer->set_transfer_mode(NetworkedMultiplayerPeer::TRANSFER_MODE_RELIABLE);
-		network_peer->put_packet(packet.ptr(), packet.size());
-
-		psc->confirmed_peers.insert(E->get(), false); //insert into confirmed, but as false since it was not confirmed
-	}
-
-	//take chance and set transfer mode, since all send methods will use it
-	network_peer->set_transfer_mode(p_unreliable ? NetworkedMultiplayerPeer::TRANSFER_MODE_UNRELIABLE : NetworkedMultiplayerPeer::TRANSFER_MODE_RELIABLE);
-
-	if (has_all_peers) {
-
-		//they all have verified paths, so send fast
-		network_peer->set_target_peer(p_to); //to all of you
-		network_peer->put_packet(packet_cache.ptr(), ofs); //a message with love
-	} else {
-		//not all verified path, so send one by one
-
-		//apend path at the end, since we will need it for some packets
-		CharString pname = String(from_path).utf8();
-		int path_len = encode_cstring(pname.get_data(), NULL);
-		MAKE_ROOM(ofs + path_len);
-		encode_cstring(pname.get_data(), &packet_cache[ofs]);
-
-		for (Set<int>::Element *E = connected_peers.front(); E; E = E->next()) {
-
-			if (p_to < 0 && E->get() == -p_to)
-				continue; //continue, excluded
-
-			if (p_to > 0 && E->get() != p_to)
-				continue; //continue, not for this peer
-
-			Map<int, bool>::Element *F = psc->confirmed_peers.find(E->get());
-			ERR_CONTINUE(!F); //should never happen
-
-			network_peer->set_target_peer(E->get()); //to this one specifically
-
-			if (F->get() == true) {
-				//this one confirmed path, so use id
-				encode_uint32(psc->id, &packet_cache[1]);
-				network_peer->put_packet(packet_cache.ptr(), ofs);
-			} else {
-				//this one did not confirm path yet, so use entire path (sorry!)
-				encode_uint32(0x80000000 | ofs, &packet_cache[1]); //offset to path and flag
-				network_peer->put_packet(packet_cache.ptr(), ofs + path_len);
-			}
-		}
-	}
-}
-
-void SceneTree::_network_process_packet(int p_from, const uint8_t *p_packet, int p_packet_len) {
-
-	ERR_FAIL_COND(p_packet_len < 5);
-
-	uint8_t packet_type = p_packet[0];
-
-	switch (packet_type) {
-
-		case NETWORK_COMMAND_REMOTE_CALL:
-		case NETWORK_COMMAND_REMOTE_SET: {
-
-			ERR_FAIL_COND(p_packet_len < 5);
-			uint32_t target = decode_uint32(&p_packet[1]);
-
-			Node *node = NULL;
-
-			if (target & 0x80000000) {
-				//use full path (not cached yet)
-
-				int ofs = target & 0x7FFFFFFF;
-				ERR_FAIL_COND(ofs >= p_packet_len);
-
-				String paths;
-				paths.parse_utf8((const char *)&p_packet[ofs], p_packet_len - ofs);
-
-				NodePath np = paths;
-
-				node = get_root()->get_node(np);
-				if (node == NULL) {
-					ERR_EXPLAIN("Failed to get path from RPC: " + String(np));
-					ERR_FAIL_COND(node == NULL);
-				}
-			} else {
-				//use cached path
-				int id = target;
-
-				Map<int, PathGetCache>::Element *E = path_get_cache.find(p_from);
-				ERR_FAIL_COND(!E);
-
-				Map<int, PathGetCache::NodeInfo>::Element *F = E->get().nodes.find(id);
-				ERR_FAIL_COND(!F);
-
-				PathGetCache::NodeInfo *ni = &F->get();
-				//do proper caching later
-
-				node = get_root()->get_node(ni->path);
-				if (node == NULL) {
-					ERR_EXPLAIN("Failed to get cached path from RPC: " + String(ni->path));
-					ERR_FAIL_COND(node == NULL);
-				}
-			}
-
-			ERR_FAIL_COND(p_packet_len < 6);
-
-			//detect cstring end
-			int len_end = 5;
-			for (; len_end < p_packet_len; len_end++) {
-				if (p_packet[len_end] == 0) {
-					break;
-				}
-			}
-
-			ERR_FAIL_COND(len_end >= p_packet_len);
-
-			StringName name = String::utf8((const char *)&p_packet[5]);
-
-			if (packet_type == NETWORK_COMMAND_REMOTE_CALL) {
-
-				if (!node->can_call_rpc(name, p_from))
-					return;
-
-				int ofs = len_end + 1;
-
-				ERR_FAIL_COND(ofs >= p_packet_len);
-
-				int argc = p_packet[ofs];
-				Vector<Variant> args;
-				Vector<const Variant *> argp;
-				args.resize(argc);
-				argp.resize(argc);
-
-				ofs++;
-
-				for (int i = 0; i < argc; i++) {
-
-					ERR_FAIL_COND(ofs >= p_packet_len);
-					int vlen;
-					Error err = decode_variant(args[i], &p_packet[ofs], p_packet_len - ofs, &vlen);
-					ERR_FAIL_COND(err != OK);
-					//args[i]=p_packet[3+i];
-					argp[i] = &args[i];
-					ofs += vlen;
-				}
-
-				Variant::CallError ce;
-
-				node->call(name, (const Variant **)argp.ptr(), argc, ce);
-				if (ce.error != Variant::CallError::CALL_OK) {
-					String error = Variant::get_call_error_text(node, name, (const Variant **)argp.ptr(), argc, ce);
-					error = "RPC - " + error;
-					ERR_PRINTS(error);
-				}
-
-			} else {
-
-				if (!node->can_call_rset(name, p_from))
-					return;
-
-				int ofs = len_end + 1;
-
-				ERR_FAIL_COND(ofs >= p_packet_len);
-
-				Variant value;
-				decode_variant(value, &p_packet[ofs], p_packet_len - ofs);
-
-				bool valid;
-
-				node->set(name, value, &valid);
-				if (!valid) {
-					String error = "Error setting remote property '" + String(name) + "', not found in object of type " + node->get_class();
-					ERR_PRINTS(error);
-				}
-			}
-
-		} break;
-		case NETWORK_COMMAND_SIMPLIFY_PATH: {
-
-			ERR_FAIL_COND(p_packet_len < 5);
-			int id = decode_uint32(&p_packet[1]);
-
-			String paths;
-			paths.parse_utf8((const char *)&p_packet[5], p_packet_len - 5);
-
-			NodePath path = paths;
-
-			if (!path_get_cache.has(p_from)) {
-				path_get_cache[p_from] = PathGetCache();
-			}
-
-			PathGetCache::NodeInfo ni;
-			ni.path = path;
-			ni.instance = 0;
-
-			path_get_cache[p_from].nodes[id] = ni;
-
-			{
-				//send ack
-
-				//encode path
-				CharString pname = String(path).utf8();
-				int len = encode_cstring(pname.get_data(), NULL);
-
-				Vector<uint8_t> packet;
-
-				packet.resize(1 + len);
-				packet[0] = NETWORK_COMMAND_CONFIRM_PATH;
-				encode_cstring(pname.get_data(), &packet[1]);
-
-				network_peer->set_transfer_mode(NetworkedMultiplayerPeer::TRANSFER_MODE_RELIABLE);
-				network_peer->set_target_peer(p_from);
-				network_peer->put_packet(packet.ptr(), packet.size());
-			}
-		} break;
-		case NETWORK_COMMAND_CONFIRM_PATH: {
-
-			String paths;
-			paths.parse_utf8((const char *)&p_packet[1], p_packet_len - 1);
-
-			NodePath path = paths;
-
-			PathSentCache *psc = path_send_cache.getptr(path);
-			ERR_FAIL_COND(!psc);
-
-			Map<int, bool>::Element *E = psc->confirmed_peers.find(p_from);
-			ERR_FAIL_COND(!E);
-			E->get() = true;
-		} break;
-	}
-}
-
-void SceneTree::_network_poll() {
-
-	if (!network_peer.is_valid() || network_peer->get_connection_status() == NetworkedMultiplayerPeer::CONNECTION_DISCONNECTED)
-		return;
-
-	network_peer->poll();
-
-	if (!network_peer.is_valid()) //it's possible that polling might have resulted in a disconnection, so check here
-		return;
-
-	while (network_peer->get_available_packet_count()) {
-
-		int sender = network_peer->get_packet_peer();
-		const uint8_t *packet;
-		int len;
-
-		Error err = network_peer->get_packet(&packet, len);
-		if (err != OK) {
-			ERR_PRINT("Error getting packet!");
-		}
-
-		rpc_sender_id = sender;
-		_network_process_packet(sender, packet, len);
-		rpc_sender_id = 0;
-
-		if (!network_peer.is_valid()) {
-			break; //it's also possible that a packet or RPC caused a disconnection, so also check here
-		}
-	}
+	return multiplayer_api->is_refusing_new_network_connections();
 }
 
 void SceneTree::_bind_methods() {
@@ -2196,6 +1790,8 @@ void SceneTree::_bind_methods() {
 
 	ClassDB::bind_method(D_METHOD("_change_scene"), &SceneTree::_change_scene);
 
+	ClassDB::bind_method(D_METHOD("set_multiplayer_api", "multiplayer_api"), &SceneTree::set_multiplayer_api);
+	ClassDB::bind_method(D_METHOD("get_multiplayer_api"), &SceneTree::get_multiplayer_api);
 	ClassDB::bind_method(D_METHOD("set_network_peer", "peer"), &SceneTree::set_network_peer);
 	ClassDB::bind_method(D_METHOD("get_network_peer"), &SceneTree::get_network_peer);
 	ClassDB::bind_method(D_METHOD("is_network_server"), &SceneTree::is_network_server);
@@ -2225,6 +1821,7 @@ void SceneTree::_bind_methods() {
 	ADD_PROPERTY(PropertyInfo(Variant::OBJECT, "current_scene", PROPERTY_HINT_RESOURCE_TYPE, "Node", 0), "set_current_scene", "get_current_scene");
 	ADD_PROPERTY(PropertyInfo(Variant::OBJECT, "network_peer", PROPERTY_HINT_RESOURCE_TYPE, "NetworkedMultiplayerPeer", 0), "set_network_peer", "get_network_peer");
 	ADD_PROPERTY(PropertyInfo(Variant::OBJECT, "root", PROPERTY_HINT_RESOURCE_TYPE, "Node", 0), "", "get_root");
+	ADD_PROPERTY(PropertyInfo(Variant::OBJECT, "multiplayer_api", PROPERTY_HINT_RESOURCE_TYPE, "MultiplayerAPI", 0), "set_multiplayer_api", "get_multiplayer_api");
 
 	ADD_SIGNAL(MethodInfo("tree_changed"));
 	ADD_SIGNAL(MethodInfo("node_added", PropertyInfo(Variant::OBJECT, "node")));
@@ -2320,7 +1917,6 @@ SceneTree::SceneTree() {
 	call_lock = 0;
 	root_lock = 0;
 	node_count = 0;
-	rpc_sender_id = 0;
 
 	//create with mainloop
 
@@ -2329,6 +1925,9 @@ SceneTree::SceneTree() {
 	if (!root->get_world().is_valid())
 		root->set_world(Ref<World>(memnew(World)));
 
+	// Initialize network state
+	set_multiplayer_api(Ref<MultiplayerAPI>(memnew(MultiplayerAPI)));
+
 	//root->set_world_2d( Ref<World2D>( memnew( World2D )));
 	root->set_as_audio_listener(true);
 	root->set_as_audio_listener_2d(true);
@@ -2423,8 +2022,6 @@ SceneTree::SceneTree() {
 
 	live_edit_root = NodePath("/root");
 
-	last_send_cache_id = 1;
-
 #endif
 
 	use_font_oversampling = false;
diff --git a/scene/main/scene_tree.h b/scene/main/scene_tree.h
index c5357762ec..203c1d9c9c 100644
--- a/scene/main/scene_tree.h
+++ b/scene/main/scene_tree.h
@@ -31,7 +31,7 @@
 #ifndef SCENE_MAIN_LOOP_H
 #define SCENE_MAIN_LOOP_H
 
-#include "io/networked_multiplayer_peer.h"
+#include "io/multiplayer_api.h"
 #include "os/main_loop.h"
 #include "os/thread_safe.h"
 #include "scene/resources/mesh.h"
@@ -185,16 +185,8 @@ private:
 
 	///network///
 
-	enum NetworkCommands {
-		NETWORK_COMMAND_REMOTE_CALL,
-		NETWORK_COMMAND_REMOTE_SET,
-		NETWORK_COMMAND_SIMPLIFY_PATH,
-		NETWORK_COMMAND_CONFIRM_PATH,
-	};
-
-	Ref<NetworkedMultiplayerPeer> network_peer;
+	Ref<MultiplayerAPI> multiplayer_api;
 
-	Set<int> connected_peers;
 	void _network_peer_connected(int p_id);
 	void _network_peer_disconnected(int p_id);
 
@@ -202,39 +194,9 @@ private:
 	void _connection_failed();
 	void _server_disconnected();
 
-	int rpc_sender_id;
-
-	//path sent caches
-	struct PathSentCache {
-		Map<int, bool> confirmed_peers;
-		int id;
-	};
-
-	HashMap<NodePath, PathSentCache> path_send_cache;
-	int last_send_cache_id;
-
-	//path get caches
-	struct PathGetCache {
-		struct NodeInfo {
-			NodePath path;
-			ObjectID instance;
-		};
-
-		Map<int, NodeInfo> nodes;
-	};
-
-	Map<int, PathGetCache> path_get_cache;
-
-	Vector<uint8_t> packet_cache;
-
-	void _network_process_packet(int p_from, const uint8_t *p_packet, int p_packet_len);
-	void _network_poll();
-
 	static SceneTree *singleton;
 	friend class Node;
 
-	void _rpc(Node *p_from, int p_to, bool p_unreliable, bool p_set, const StringName &p_name, const Variant **p_arg, int p_argcount);
-
 	void tree_changed();
 	void node_added(Node *p_node);
 	void node_removed(Node *p_node);
@@ -450,6 +412,8 @@ public:
 
 	//network API
 
+	Ref<MultiplayerAPI> get_multiplayer_api() const;
+	void set_multiplayer_api(Ref<MultiplayerAPI> p_multiplayer_api);
 	void set_network_peer(const Ref<NetworkedMultiplayerPeer> &p_network_peer);
 	Ref<NetworkedMultiplayerPeer> get_network_peer() const;
 	bool is_network_server() const;