com.unity.netcode.gameobjects@1.7.0

The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/) and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).

Additional documentation and release notes are available at [Multiplayer Documentation](https://docs-multiplayer.unity3d.com).

## [1.7.0] - 2023-10-11

### Added

- exposed NetworkObject.GetNetworkBehaviourAtOrderIndex as a public API (#2724)
- Added context menu tool that provides users with the ability to quickly update the GlobalObjectIdHash value for all in-scene placed prefab instances that were created prior to adding a NetworkObject component to it. (#2707)
- Added methods NetworkManager.SetPeerMTU and NetworkManager.GetPeerMTU to be able to set MTU sizes per-peer (#2676)
- Added `GenerateSerializationForGenericParameterAttribute`, which can be applied to user-created Network Variable types to ensure the codegen generates serialization for the generic types they wrap. (#2694)
- Added `GenerateSerializationForTypeAttribute`, which can be applied to any class or method to ensure the codegen generates serialization for the specific provided type. (#2694)
- Exposed `NetworkVariableSerialization<T>.Read`, `NetworkVariableSerialization<T>.Write`, `NetworkVariableSerialization<T>.AreEqual`, and `NetworkVariableSerialization<T>.Duplicate` to further support the creation of user-created network variables by allowing users to access the generated serialization methods and serialize generic types efficiently without boxing. (#2694)
- Added `NetworkVariableBase.MarkNetworkBehaviourDirty` so that user-created network variable types can mark their containing `NetworkBehaviour` to be processed by the update loop. (#2694)

### Fixed

- Fixed issue where the server side `NetworkSceneManager` instance was not adding the currently active scene to its list of scenes loaded. (#2723)
- Generic NetworkBehaviour types no longer result in compile errors or runtime errors (#2720)
- Rpcs within Generic NetworkBehaviour types can now serialize parameters of the class's generic types (but may not have generic types of their own) (#2720)
- Errors are no longer thrown when entering play mode with domain reload disabled (#2720)
- NetworkSpawn is now correctly called each time when entering play mode with scene reload disabled (#2720)
- NetworkVariables of non-integer types will no longer break the inspector (#2714)
- NetworkVariables with NonSerializedAttribute will not appear in the inspector (#2714)
- Fixed issue where `UnityTransport` would attempt to establish WebSocket connections even if using UDP/DTLS Relay allocations when the build target was WebGL. This only applied to working in the editor since UDP/DTLS can't work in the browser. (#2695)
- Fixed issue where a `NetworkBehaviour` component's `OnNetworkDespawn` was not being invoked on the host-server side for an in-scene placed `NetworkObject` when a scene was unloaded (during a scene transition) and the `NetworkBehaviour` component was positioned/ordered before the `NetworkObject` component. (#2685)
- Fixed issue where `SpawnWithObservers` was not being honored when `NetworkConfig.EnableSceneManagement` was disabled. (#2682)
- Fixed issue where `NetworkAnimator` was not internally tracking changes to layer weights which prevented proper layer weight synchronization back to the original layer weight value. (#2674)
- Fixed "writing past the end of the buffer" error when calling ResetDirty() on managed network variables that are larger than 256 bytes when serialized. (#2670)
- Fixed issue where generation of the `DefaultNetworkPrefabs` asset was not enabled by default. (#2662)
- Fixed issue where the `GlobalObjectIdHash` value could be updated but the asset not marked as dirty. (#2662)
- Fixed issue where the `GlobalObjectIdHash` value of a (network) prefab asset could be assigned an incorrect value when editing the prefab in a temporary scene. (#2662)
- Fixed issue where the `GlobalObjectIdHash` value generated after creating a (network) prefab from an object constructed within the scene would not be the correct final value in a stand alone build. (#2662)

### Changed

- Updated dependency on `com.unity.transport` to version 1.4.0. (#2716)

Runtime/Messaging/NetworkMessageManager.cs

@@ -99,6 +99,8 @@ namespace Unity.Netcode
         public int NonFragmentedMessageMaxSize = DefaultNonFragmentedMessageMaxSize;
         public int FragmentedMessageMaxSize = int.MaxValue;
 
+        public Dictionary<ulong, int> PeerMTUSizes = new Dictionary<ulong, int>();
+
         internal struct MessageWithHandler
         {
             public Type MessageType;
@@ -497,6 +499,7 @@ namespace Unity.Netcode
             m_SendQueues.Remove(clientId);
 
             m_PerClientMessageVersions.Remove(clientId);
+            PeerMTUSizes.Remove(clientId);
         }
 
         internal void CleanupDisconnectedClients()
@@ -678,6 +681,21 @@ namespace Unity.Netcode
                     continue;
                 }
 
+                var startSize = NonFragmentedMessageMaxSize;
+                if (delivery != NetworkDelivery.ReliableFragmentedSequenced)
+                {
+                    if (PeerMTUSizes.TryGetValue(clientId, out var clientMaxSize))
+                    {
+                        maxSize = clientMaxSize;
+                    }
+                    startSize = maxSize;
+                    if (tmpSerializer.Position >= maxSize)
+                    {
+                        Debug.LogError($"MTU size for {clientId} is too small to contain a message of type {typeof(TMessageType).FullName}");
+                        continue;
+                    }
+                }
+
                 for (var hookIdx = 0; hookIdx < m_Hooks.Count; ++hookIdx)
                 {
                     m_Hooks[hookIdx].OnBeforeSendMessage(clientId, ref message, delivery);
@@ -686,7 +704,7 @@ namespace Unity.Netcode
                 var sendQueueItem = m_SendQueues[clientId];
                 if (sendQueueItem.Length == 0)
                 {
-                    sendQueueItem.Add(new SendQueueItem(delivery, NonFragmentedMessageMaxSize, Allocator.TempJob, maxSize));
+                    sendQueueItem.Add(new SendQueueItem(delivery, startSize, Allocator.TempJob, maxSize));
                     sendQueueItem.ElementAt(0).Writer.Seek(sizeof(NetworkBatchHeader));
                 }
                 else
@@ -694,7 +712,7 @@ namespace Unity.Netcode
                     ref var lastQueueItem = ref sendQueueItem.ElementAt(sendQueueItem.Length - 1);
                     if (lastQueueItem.NetworkDelivery != delivery || lastQueueItem.Writer.MaxCapacity - lastQueueItem.Writer.Position < tmpSerializer.Length + headerSerializer.Length)
                     {
-                        sendQueueItem.Add(new SendQueueItem(delivery, NonFragmentedMessageMaxSize, Allocator.TempJob, maxSize));
+                        sendQueueItem.Add(new SendQueueItem(delivery, startSize, Allocator.TempJob, maxSize));
                         sendQueueItem.ElementAt(sendQueueItem.Length - 1).Writer.Seek(sizeof(NetworkBatchHeader));
                     }
                 }