Merge branch 'develop-2.0.0' into chore/simplify-accessors-network-object

# Conflicts:
#	com.unity.netcode.gameobjects/Runtime/Core/NetworkObject.cs

Author: noellie-velez

com.unity.netcode.gameobjects/Runtime/Core/NetworkManager.cs

@@ -313,11 +313,11 @@ internal void NetworkTransformRegistration(NetworkObject networkObject, bool onU
 
         private void UpdateTopology()
         {
-            var transportTopology = IsListening ? NetworkConfig.NetworkTransport.CurrentTopology() : NetworkConfig.NetworkTopology;
+            var transportTopology = IsListening && IsConnectedClient ? NetworkConfig.NetworkTransport.CurrentTopology() : NetworkConfig.NetworkTopology;
             if (transportTopology != NetworkConfig.NetworkTopology)
             {
-                NetworkLog.LogErrorServer($"[Topology Mismatch] Transport detected an issue with the topology ({transportTopology} | {NetworkConfig.NetworkTopology}) usage or setting! Disconnecting from session.");
-                Shutdown();
+                NetworkLog.LogErrorServer($"[Topology Mismatch][{transportTopology}:{transportTopology.GetType().Name}][NetworkManager.NetworkConfig:{NetworkConfig.NetworkTopology}] Transport detected an issue with the topology usage or setting! Disconnecting from session.");
+                Shutdown(true);
             }
             else
             {
@@ -504,6 +504,7 @@ public void NetworkUpdate(NetworkUpdateStage updateStage)
                                 ShutdownInternal();
                             }
                         }
+
                     }
                     break;
             }

com.unity.netcode.gameobjects/Runtime/Core/NetworkObject.cs

@@ -1345,6 +1345,15 @@ public void SetSceneObjectStatus(bool isSceneObject = false)
 
         internal readonly HashSet<ulong> Observers = new HashSet<ulong>();
 
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        internal void AddObserver(ulong clientId)
+        {
+#if NETCODE_DEBUG_OBSERVERS
+            Debug.Log($"[{nameof(NetworkObject)}][{name}-{NetworkObjectId}] Adding Client-{clientId} as an observer.");
+#endif
+            Observers.Add(clientId);
+        }
+
 #if MULTIPLAYER_TOOLS
         private string m_CachedNameForMetrics;
 #endif
@@ -1494,7 +1503,7 @@ public void NetworkShow(ulong clientId)
                 return;
             }
             NetworkManagerOwner.SpawnManager.MarkObjectForShowingTo(this, clientId);
-            Observers.Add(clientId);
+            AddObserver(clientId);
         }
 
 
@@ -3288,7 +3297,7 @@ internal static NetworkObject Deserialize(in SerializedObject serializedObject,
             {
                 foreach (var observer in serializedObject.Observers)
                 {
-                    networkObject.Observers.Add(observer);
+                    networkObject.AddObserver(observer);
                 }
             }
 
@@ -3308,11 +3317,11 @@ internal static NetworkObject Deserialize(in SerializedObject serializedObject,
                     if (networkObject.IsPlayerObject)
                     {
                         // If it is another player, then make sure the local player is aware of the player
-                        playerObject.Observers.Add(networkObject.OwnerClientId);
+                        playerObject.AddObserver(networkObject.OwnerClientId);
                     }
 
                     // Assure the local player has observability
-                    networkObject.Observers.Add(playerObject.OwnerClientId);
+                    networkObject.AddObserver(playerObject.OwnerClientId);
 
                     // If it is a player object, then add it to all known spawned NetworkObjects that spawn with observers
                     if (networkObject.IsPlayerObject)
@@ -3321,7 +3330,7 @@ internal static NetworkObject Deserialize(in SerializedObject serializedObject,
                         {
                             if (netObject.Value.SpawnWithObservers)
                             {
-                                netObject.Value.Observers.Add(networkObject.OwnerClientId);
+                                netObject.Value.AddObserver(networkObject.OwnerClientId);
                             }
                         }
                     }
@@ -3333,7 +3342,7 @@ internal static NetworkObject Deserialize(in SerializedObject serializedObject,
                         // Add all known players to the observers list if they don't already exist
                         foreach (var player in networkManager.SpawnManager.PlayerObjects)
                         {
-                            networkObject.Observers.Add(player.OwnerClientId);
+                            networkObject.AddObserver(player.OwnerClientId);
                         }
                     }
                 }

com.unity.netcode.gameobjects/Runtime/Messaging/Messages/ConnectionApprovedMessage.cs

@@ -158,7 +158,7 @@ public void Serialize(FastBufferWriter writer, int targetVersion)
                 {
                     if (sobj.SpawnWithObservers && (sobj.CheckObjectVisibility == null || sobj.CheckObjectVisibility(OwnerClientId)))
                     {
-                        sobj.Observers.Add(OwnerClientId);
+                        sobj.AddObserver(OwnerClientId);
                         // In distributed authority mode, we send the currently known observers of each NetworkObject to the client being synchronized.
                         var serializedObject = sobj.Serialize(OwnerClientId, IsDistributedAuthority);
                         serializedObject.Serialize(writer);

com.unity.netcode.gameobjects/Runtime/Messaging/Messages/CreateObjectMessage.cs

@@ -208,7 +208,7 @@ internal static void CreateObject(ref NetworkManager networkManager, ulong sende
                     // Update the observers for this instance
                     for (int i = 0; i < clientList.Count; i++)
                     {
-                        networkObject.Observers.Add(clientList[i]);
+                        networkObject.AddObserver(clientList[i]);
                     }
 
                     // Mock CMB Service and forward to all clients

com.unity.netcode.gameobjects/Runtime/Spawning/NetworkSpawnManager.cs

@@ -81,26 +81,33 @@ private void AddPlayerObject(NetworkObject playerObject)
                 }
             }
 
+            var cmbService = NetworkManager.CMBServiceConnection;
+            var sceneManagement = NetworkManager.NetworkConfig.EnableSceneManagement;
+
             foreach (var player in m_PlayerObjects)
             {
+                // When connected to the CMB service, scene management is disabled, and it is the local player, we do
+                // not want to add the newly connected player to the observers list of the local player as that will be
+                // done when the local client shows the NetworkObject to the newly connected client.
+                var shouldAddObserver = cmbService && !sceneManagement ? !player.IsLocalPlayer : true;
                 // If the player's SpawnWithObservers is not set then do not add the new player object's owner as an observer.
-                if (player.SpawnWithObservers)
+                if (player.SpawnWithObservers && shouldAddObserver)
                 {
-                    player.Observers.Add(playerObject.OwnerClientId);
+                    player.AddObserver(playerObject.OwnerClientId);
                 }
 
                 // If the new player object's SpawnWithObservers is not set then do not add this player as an observer to the new player object.
                 if (playerObject.SpawnWithObservers)
                 {
-                    playerObject.Observers.Add(player.OwnerClientId);
+                    playerObject.AddObserver(player.OwnerClientId);
                 }
             }
 
             // Only if spawn with observers is set or we are using a distributed authority network topology and this is the client's player should we add
             // the owner as an observer.
             if (playerObject.SpawnWithObservers || (NetworkManager.DistributedAuthorityMode && NetworkManager.LocalClientId == playerObject.OwnerClientId))
             {
-                playerObject.Observers.Add(playerObject.OwnerClientId);
+                playerObject.AddObserver(playerObject.OwnerClientId);
             }
 
             m_PlayerObjects.Add(playerObject);
@@ -1066,7 +1073,7 @@ internal void AuthorityLocalSpawn([NotNull] NetworkObject networkObject, ulong n
                 // (authority should not take into consideration networkObject.CheckObjectVisibility when SpawnWithObservers is false)
                 if (!networkObject.SpawnWithObservers)
                 {
-                    networkObject.Observers.Add(ownerClientId);
+                    networkObject.AddObserver(ownerClientId);
                 }
                 else
                 {
@@ -1077,15 +1084,15 @@ internal void AuthorityLocalSpawn([NotNull] NetworkObject networkObject, ulong n
                         {
                             continue;
                         }
-                        networkObject.Observers.Add(clientId);
+                        networkObject.AddObserver(clientId);
                     }
 
                     // Sanity check to make sure the owner is always included
                     // Itentionally checking as opposed to just assigning in order to generate notification.
                     if (!networkObject.Observers.Contains(ownerClientId))
                     {
                         Debug.LogError($"Client-{ownerClientId} is the owner of {networkObject.name} but is not an observer! Adding owner, but there is a bug in observer synchronization!");
-                        networkObject.Observers.Add(ownerClientId);
+                        networkObject.AddObserver(ownerClientId);
                     }
                 }
             }
@@ -1174,7 +1181,7 @@ internal void SpawnNetworkObjectLocallyCommon(NetworkObject networkObject, ulong
                 // If running as a server only, then make sure to always add the server's client identifier
                 if (!NetworkManager.IsHost)
                 {
-                    networkObject.Observers.Add(NetworkManager.LocalClientId);
+                    networkObject.AddObserver(NetworkManager.LocalClientId);
                 }
 
                 // Add client observers
@@ -1185,7 +1192,7 @@ internal void SpawnNetworkObjectLocallyCommon(NetworkObject networkObject, ulong
                     {
                         continue;
                     }
-                    networkObject.Observers.Add(NetworkManager.ConnectedClientsIds[i]);
+                    networkObject.AddObserver(NetworkManager.ConnectedClientsIds[i]);
                 }
             }
 
@@ -1745,15 +1752,15 @@ internal void UpdateObservedNetworkObjects(ulong clientId)
                     // If the client is not part of the observers and spawn with observers is enabled on this instance or the clientId is the server/host/DAHost
                     if (!sobj.Observers.Contains(clientId) && (sobj.SpawnWithObservers || clientId == NetworkManager.ServerClientId))
                     {
-                        sobj.Observers.Add(clientId);
+                        sobj.AddObserver(clientId);
                     }
                 }
                 else
                 {
                     // CheckObject visibility overrides SpawnWithObservers under this condition
                     if (sobj.CheckObjectVisibility(clientId))
                     {
-                        sobj.Observers.Add(clientId);
+                        sobj.AddObserver(clientId);
                     }
                     else // Otherwise, if the observers contains the clientId (shouldn't happen) then remove it since CheckObjectVisibility returned false
                     {