Move routing info into message header, make relay type-agnostic

extensions/include/extensions/multiplayer/networkmanager.h

@@ -90,7 +90,6 @@ class NetworkManager : public MxCore {
 
 	RemotePlayer* CreateAndSpawnPlayer(uint32_t p_peerId, uint8_t p_actorId, uint8_t p_displayActorIndex);
 
-	void HandleJoin(const PlayerJoinMsg& p_msg);
 	void HandleLeave(const PlayerLeaveMsg& p_msg);
 	void HandleState(const PlayerStateMsg& p_msg);
 	void HandleHostAssign(const HostAssignMsg& p_msg);

extensions/include/extensions/multiplayer/protocol.h

@@ -10,8 +10,12 @@ class LegoPathActor;
 namespace Multiplayer
 {
 
+// Routing target constants for MessageHeader.target
+const uint32_t TARGET_BROADCAST = 0;          // Broadcast to all except sender
+const uint32_t TARGET_HOST = 0xFFFFFFFF;      // Send to host only
+const uint32_t TARGET_BROADCAST_ALL = 0xFFFFFFFE; // Broadcast to all including sender
+
 enum MessageType : uint8_t {
-	MSG_JOIN = 1,
 	MSG_LEAVE = 2,
 	MSG_STATE = 3,
 	MSG_HOST_ASSIGN = 4,
@@ -74,12 +78,7 @@ struct MessageHeader {
 	uint8_t type;
 	uint32_t peerId;
 	uint32_t sequence;
-};
-
-struct PlayerJoinMsg {
-	MessageHeader header;
-	uint8_t actorId;
-	char name[20];
+	uint32_t target;
 };
 
 struct PlayerLeaveMsg {
@@ -115,10 +114,9 @@ struct RequestSnapshotMsg {
 };
 
 // Host -> specific client: full world state blob (variable length)
-// Relay reads targetPeerId at offset 9 and routes to that peer only.
+// Relay reads header.target and routes to that peer only.
 struct WorldSnapshotMsg {
 	MessageHeader header;
-	uint32_t targetPeerId;
 	uint16_t dataLength;
 	// Followed by dataLength bytes of serialized plant + building state
 };

extensions/src/multiplayer/networkmanager.cpp

@@ -312,7 +312,7 @@ void NetworkManager::BroadcastLocalState()
 	}
 
 	PlayerStateMsg msg{};
-	msg.header = {MSG_STATE, m_localPeerId, m_sequence++};
+	msg.header = {MSG_STATE, m_localPeerId, m_sequence++, TARGET_BROADCAST};
 	msg.actorId = actorId;
 	msg.worldId = (int8_t) currentWorld->GetWorldId();
 	msg.vehicleType = DetectVehicleType(userActor);
@@ -397,16 +397,6 @@ void NetworkManager::ProcessIncomingPackets()
 			}
 			break;
 		}
-		case MSG_JOIN: {
-			PlayerJoinMsg msg;
-			if (DeserializeMsg(data, length, msg) && msg.header.type == MSG_JOIN) {
-				msg.name[sizeof(msg.name) - 1] = '\0';
-				if (IsValidActorId(msg.actorId)) {
-					HandleJoin(msg);
-				}
-			}
-			break;
-		}
 		case MSG_LEAVE: {
 			PlayerLeaveMsg msg;
 			if (DeserializeMsg(data, length, msg) && msg.header.type == MSG_LEAVE) {
@@ -494,18 +484,6 @@ RemotePlayer* NetworkManager::CreateAndSpawnPlayer(uint32_t p_peerId, uint8_t p_
 	return ptr;
 }
 
-void NetworkManager::HandleJoin(const PlayerJoinMsg& p_msg)
-{
-	uint32_t peerId = p_msg.header.peerId;
-
-	if (m_remotePlayers.count(peerId)) {
-		return;
-	}
-
-	CreateAndSpawnPlayer(peerId, p_msg.actorId, p_msg.actorId - 1);
-	NotifyPlayerCountChanged();
-}
-
 void NetworkManager::HandleLeave(const PlayerLeaveMsg& p_msg)
 {
 	RemoveRemotePlayer(p_msg.header.peerId);
@@ -594,7 +572,7 @@ void NetworkManager::SendEmote(uint8_t p_emoteId)
 	m_thirdPersonCamera.TriggerEmote(p_emoteId);
 
 	EmoteMsg msg{};
-	msg.header = {MSG_EMOTE, m_localPeerId, m_sequence++};
+	msg.header = {MSG_EMOTE, m_localPeerId, m_sequence++, TARGET_BROADCAST};
 	msg.emoteId = p_emoteId;
 	SendMessage(msg);
 }
@@ -713,7 +691,7 @@ bool NetworkManager::IsClonedCharacter(const char* p_name) const
 void NetworkManager::SendCustomize(uint32_t p_targetPeerId, uint8_t p_changeType, uint8_t p_partIndex)
 {
 	CustomizeMsg msg{};
-	msg.header = {MSG_CUSTOMIZE, m_localPeerId, m_sequence++};
+	msg.header = {MSG_CUSTOMIZE, m_localPeerId, m_sequence++, TARGET_BROADCAST_ALL};
 	msg.targetPeerId = p_targetPeerId;
 	msg.changeType = p_changeType;
 	msg.partIndex = p_partIndex;

extensions/src/multiplayer/server/gameroom.ts

@@ -1,14 +1,12 @@
 import {
 	HEADER_SIZE,
-	MSG_CUSTOMIZE,
-	MSG_REQUEST_SNAPSHOT,
-	MSG_WORLD_EVENT_REQUEST,
-	MSG_WORLD_SNAPSHOT,
-	SNAPSHOT_MIN_SIZE,
+	TARGET_BROADCAST,
+	TARGET_HOST,
+	TARGET_BROADCAST_ALL,
 	createAssignIdMsg,
 	createHostAssignMsg,
 	createLeaveMsg,
-	readTargetPeerId,
+	readTarget,
 	stampSender,
 } from "./protocol";
 import type { Env } from "./relay";
@@ -166,30 +164,17 @@ export class GameRoom implements DurableObject {
 			return;
 		}
 
-		const msgType = data[0];
 		const stamped = stampSender(data, peerId);
+		const target = readTarget(stamped);
 
-		if (
-			msgType === MSG_REQUEST_SNAPSHOT ||
-			msgType === MSG_WORLD_EVENT_REQUEST
-		) {
+		if (target === TARGET_BROADCAST) {
+			this.broadcastExcept(stamped.buffer, peerId);
+		} else if (target === TARGET_HOST) {
 			this.sendToHost(stamped);
-		} else if (
-			msgType === MSG_WORLD_SNAPSHOT &&
-			data.length >= SNAPSHOT_MIN_SIZE
-		) {
-			const targetId = readTargetPeerId(stamped);
-			if (targetId === 0) {
-				this.broadcastExcept(stamped.buffer, peerId);
-			} else {
-				this.sendToTarget(stamped);
-			}
-		} else if (msgType === MSG_CUSTOMIZE) {
-			// Broadcast to all including sender so the clicker sees effects
-			// on the target's clone on their own screen.
+		} else if (target === TARGET_BROADCAST_ALL) {
 			this.broadcast(stamped.buffer);
 		} else {
-			this.broadcastExcept(stamped.buffer, peerId);
+			this.sendToTarget(stamped, target);
 		}
 	}
 
@@ -200,8 +185,7 @@ export class GameRoom implements DurableObject {
 		}
 	}
 
-	private sendToTarget(data: Uint8Array): void {
-		const targetId = readTargetPeerId(data);
+	private sendToTarget(data: Uint8Array, targetId: number): void {
 		const targetWs = this.connections.get(targetId);
 		if (targetWs) {
 			if (!this.trySend(targetWs, data.buffer)) {

extensions/src/multiplayer/server/protocol.ts

@@ -1,30 +1,27 @@
 // Protocol constants — must stay in sync with protocol.h
 
-// MessageHeader binary layout: type(1) + peerId(4) + sequence(4) = 9 bytes
-export const HEADER_SIZE = 9;
+// MessageHeader binary layout: type(1) + peerId(4) + sequence(4) + target(4) = 13 bytes
+export const HEADER_SIZE = 13;
 export const PEER_ID_OFFSET = 1;
 export const SEQUENCE_OFFSET = 5;
+export const TARGET_OFFSET = 9;
 
-// Message types the relay inspects for routing decisions.
-// All other types are broadcast to every peer in the room.
+// Routing target constants
+export const TARGET_BROADCAST = 0;
+export const TARGET_HOST = 0xffffffff;
+export const TARGET_BROADCAST_ALL = 0xfffffffe;
+
+// Message types used by server message constructors only.
 export const MSG_LEAVE = 2;
 export const MSG_HOST_ASSIGN = 4;
-export const MSG_REQUEST_SNAPSHOT = 5;
-export const MSG_WORLD_SNAPSHOT = 6;
-export const MSG_WORLD_EVENT_REQUEST = 8;
-export const MSG_CUSTOMIZE = 10;
 export const MSG_ASSIGN_ID = 0xff;
 
 // AssignIdMsg: compact server-only message — type(1) + peerId(4) + maxActors(1)
 const ASSIGN_ID_SIZE = 1 + 4 + 1;
 
-// HostAssignMsg: header(9) + hostPeerId(4)
+// HostAssignMsg: header(13) + hostPeerId(4)
 const HOST_ASSIGN_SIZE = HEADER_SIZE + 4;
 
-// WorldSnapshotMsg: header(9) + targetPeerId(4) + dataLength(2) + data...
-export const SNAPSHOT_TARGET_OFFSET = HEADER_SIZE;
-export const SNAPSHOT_MIN_SIZE = HEADER_SIZE + 4 + 2;
-
 export function createAssignIdMsg(peerId: number, maxActors: number): ArrayBuffer {
 	const buf = new ArrayBuffer(ASSIGN_ID_SIZE);
 	const view = new DataView(buf);
@@ -40,6 +37,7 @@ export function createHostAssignMsg(hostPeerId: number): ArrayBuffer {
 	view.setUint8(0, MSG_HOST_ASSIGN);
 	view.setUint32(PEER_ID_OFFSET, 0, true);
 	view.setUint32(SEQUENCE_OFFSET, 0, true);
+	view.setUint32(TARGET_OFFSET, 0, true);
 	view.setUint32(HEADER_SIZE, hostPeerId, true);
 	return buf;
 }
@@ -50,6 +48,7 @@ export function createLeaveMsg(peerId: number): ArrayBuffer {
 	view.setUint8(0, MSG_LEAVE);
 	view.setUint32(PEER_ID_OFFSET, peerId, true);
 	view.setUint32(SEQUENCE_OFFSET, 0, true);
+	view.setUint32(TARGET_OFFSET, 0, true);
 	return buf;
 }
 
@@ -61,6 +60,6 @@ export function stampSender(data: Uint8Array, peerId: number): Uint8Array {
 	return stamped;
 }
 
-export function readTargetPeerId(data: Uint8Array): number {
-	return new DataView(data.buffer).getUint32(SNAPSHOT_TARGET_OFFSET, true);
+export function readTarget(data: Uint8Array): number {
+	return new DataView(data.buffer).getUint32(TARGET_OFFSET, true);
 }

extensions/src/multiplayer/worldstatesync.cpp

@@ -232,7 +232,7 @@ MxBool WorldStateSync::HandleSkyLightMutation(uint8_t p_entityType, uint8_t p_ch
 void WorldStateSync::SendSnapshotRequest()
 {
 	RequestSnapshotMsg msg{};
-	msg.header = {MSG_REQUEST_SNAPSHOT, m_localPeerId, m_sequence++};
+	msg.header = {MSG_REQUEST_SNAPSHOT, m_localPeerId, m_sequence++, TARGET_HOST};
 	SendMessage(msg);
 
 	m_snapshotRequested = true;
@@ -270,8 +270,7 @@ void WorldStateSync::SendWorldSnapshot(uint32_t p_targetPeerId)
 	stateBuffer[dataLength++] = (uint8_t) lightPos;
 
 	WorldSnapshotMsg msg{};
-	msg.header = {MSG_WORLD_SNAPSHOT, m_localPeerId, m_sequence++};
-	msg.targetPeerId = p_targetPeerId;
+	msg.header = {MSG_WORLD_SNAPSHOT, m_localPeerId, m_sequence++, p_targetPeerId};
 	msg.dataLength = (uint16_t) dataLength;
 
 	std::vector<uint8_t> msgBuf(sizeof(WorldSnapshotMsg) + dataLength);
@@ -284,7 +283,7 @@ void WorldStateSync::SendWorldSnapshot(uint32_t p_targetPeerId)
 void WorldStateSync::BroadcastWorldEvent(uint8_t p_entityType, uint8_t p_changeType, uint8_t p_entityIndex)
 {
 	WorldEventMsg msg{};
-	msg.header = {MSG_WORLD_EVENT, m_localPeerId, m_sequence++};
+	msg.header = {MSG_WORLD_EVENT, m_localPeerId, m_sequence++, TARGET_BROADCAST};
 	msg.entityType = p_entityType;
 	msg.changeType = p_changeType;
 	msg.entityIndex = p_entityIndex;
@@ -294,7 +293,7 @@ void WorldStateSync::BroadcastWorldEvent(uint8_t p_entityType, uint8_t p_changeT
 void WorldStateSync::SendWorldEventRequest(uint8_t p_entityType, uint8_t p_changeType, uint8_t p_entityIndex)
 {
 	WorldEventRequestMsg msg{};
-	msg.header = {MSG_WORLD_EVENT_REQUEST, m_localPeerId, m_sequence++};
+	msg.header = {MSG_WORLD_EVENT_REQUEST, m_localPeerId, m_sequence++, TARGET_HOST};
 	msg.entityType = p_entityType;
 	msg.changeType = p_changeType;
 	msg.entityIndex = p_entityIndex;