com.unity.netcode.gameobjects@2.0.0-pre.1

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).

## [2.0.0-pre.1] - 2024-06-17

### Added

- Added event `NetworkManager.OnSessionOwnerPromoted` that is invoked when a new session owner promotion occurs. (#2948)
- Added `NetworkRigidBodyBase.GetLinearVelocity` and `NetworkRigidBodyBase.SetLinearVelocity` convenience/helper methods. (#2948)
- Added `NetworkRigidBodyBase.GetAngularVelocity` and `NetworkRigidBodyBase.SetAngularVelocity` convenience/helper methods. (#2948)

### Fixed

- Fixed issue when `NetworkTransform` half float precision is enabled and ownership changes the current base position was not being synchronized. (#2948)
- Fixed issue where `OnClientConnected` not being invoked on the session owner when connecting to a new distributed authority session. (#2948)
- Fixed issue where Rigidbody micro-motion (i.e. relatively small velocities) would result in non-authority instances slightly stuttering as the body would come to a rest (i.e. no motion). Now, the threshold value can increase at higher velocities and can decrease slightly below the provided threshold to account for this. (#2948)

### Changed

- Changed the client's owned objects is now returned (`NetworkClient` and `NetworkSpawnManager`) as an array as opposed to a list for performance purposes. (#2948)
- Changed `NetworkTransfrom.TryCommitTransformToServer` to be internal as it will be removed by the final 2.0.0 release. (#2948)
- Changed `NetworkTransformEditor.OnEnable` to a virtual method to be able to customize a `NetworkTransform` derived class by creating a derived editor control from `NetworkTransformEditor`. (#2948)

Runtime/NetworkVariable/Serialization/UserNetworkVariableSerialization.cs

@@ -0,0 +1,73 @@
+namespace Unity.Netcode
+{
+    /// <summary>
+    /// This class is used to register user serialization with NetworkVariables for types
+    /// that are serialized via user serialization, such as with FastBufferReader and FastBufferWriter
+    /// extension methods. Finding those methods isn't achievable efficiently at runtime, so this allows
+    /// users to tell NetworkVariable about those extension methods (or simply pass in a lambda)
+    /// </summary>
+    /// <typeparam name="T"></typeparam>
+    public class UserNetworkVariableSerialization<T>
+    {
+        /// <summary>
+        /// The write value delegate handler definition
+        /// </summary>
+        /// <param name="writer">The <see cref="FastBufferWriter"/> to write the value of type `T`</param>
+        /// <param name="value">The value of type `T` to be written</param>
+        public delegate void WriteValueDelegate(FastBufferWriter writer, in T value);
+
+        /// <summary>
+        /// The write value delegate handler definition
+        /// </summary>
+        /// <param name="writer">The <see cref="FastBufferWriter"/> to write the value of type `T`</param>
+        /// <param name="value">The value of type `T` to be written</param>
+        public delegate void WriteDeltaDelegate(FastBufferWriter writer, in T value, in T previousValue);
+
+        /// <summary>
+        /// The read value delegate handler definition
+        /// </summary>
+        /// <param name="reader">The <see cref="FastBufferReader"/> to read the value of type `T`</param>
+        /// <param name="value">The value of type `T` to be read</param>
+        public delegate void ReadValueDelegate(FastBufferReader reader, out T value);
+
+        /// <summary>
+        /// The read value delegate handler definition
+        /// </summary>
+        /// <param name="reader">The <see cref="FastBufferReader"/> to read the value of type `T`</param>
+        /// <param name="value">The value of type `T` to be read</param>
+        public delegate void ReadDeltaDelegate(FastBufferReader reader, ref T value);
+
+        /// <summary>
+        /// The read value delegate handler definition
+        /// </summary>
+        /// <param name="reader">The <see cref="FastBufferReader"/> to read the value of type `T`</param>
+        /// <param name="value">The value of type `T` to be read</param>
+        public delegate void DuplicateValueDelegate(in T value, ref T duplicatedValue);
+
+        /// <summary>
+        /// Callback to write a value
+        /// </summary>
+        public static WriteValueDelegate WriteValue;
+
+        /// <summary>
+        /// Callback to read a value
+        /// </summary>
+        public static ReadValueDelegate ReadValue;
+
+        /// <summary>
+        /// Callback to write a delta between two values, based on computing the difference between the previous and
+        /// current values.
+        /// </summary>
+        public static WriteDeltaDelegate WriteDelta;
+
+        /// <summary>
+        /// Callback to read a delta, applying only select changes to the current value.
+        /// </summary>
+        public static ReadDeltaDelegate ReadDelta;
+
+        /// <summary>
+        /// Callback to create a duplicate of a value, used to check for dirty status.
+        /// </summary>
+        public static DuplicateValueDelegate DuplicateValue;
+    }
+}