feat: add NetworkObject and NetworkBehaviour reference types

com.unity.netcode.gameobjects/Runtime/Serialization/NetworkBehaviourReference.cs

@@ -0,0 +1,103 @@
+using System;
+using System.Runtime.CompilerServices;
+
+namespace Unity.Netcode
+{
+    /// <summary>
+    /// A helper struct for serializing <see cref="NetworkBehaviour"/>s over the network. Can be used in RPCs and <see cref="NetworkVariable{T}"/>.
+    /// Note: network ids get recycled by the NetworkManager after a while. So a reference pointing to
+    /// </summary>
+    public struct NetworkBehaviourReference : INetworkSerializable, IEquatable<NetworkBehaviourReference>
+    {
+        private NetworkObjectReference m_NetworkObjectReference;
+        private ushort m_NetworkBehaviourId;
+
+        /// <summary>
+        /// Creates a new instance of the <see cref="NetworkBehaviourReference{T}"/> struct.
+        /// </summary>
+        /// <param name="networkBehaviour">The <see cref="NetworkBehaviour"/> to reference.</param>
+        /// <exception cref="ArgumentException"></exception>
+        public NetworkBehaviourReference(NetworkBehaviour networkBehaviour)
+        {
+            if (networkBehaviour == null)
+            {
+                throw new ArgumentNullException(nameof(networkBehaviour));
+            }
+            if (networkBehaviour.NetworkObject == null)
+            {
+                throw new ArgumentException($"Cannot create {nameof(NetworkBehaviourReference)} from {nameof(NetworkBehaviour)} without a {nameof(NetworkObject)}.");
+            }
+
+            m_NetworkObjectReference = networkBehaviour.NetworkObject;
+            m_NetworkBehaviourId = networkBehaviour.NetworkBehaviourId;
+        }
+
+        /// <summary>
+        /// Tries to get the <see cref="NetworkBehaviour"/> referenced by this reference.
+        /// </summary>
+        /// <param name="networkBehaviour">The <see cref="NetworkBehaviour"/> which was found. Null if the corresponding <see cref="NetworkObject"/> was not found.</param>
+        /// <param name="networkManager">The networkmanager. Uses <see cref="NetworkManager.Singleton"/> to resolve if null.</param>
+        /// <returns>True if the <see cref="NetworkBehaviour"/> was found; False if the <see cref="NetworkBehaviour"/> was not found. This can happen if the corresponding <see cref="NetworkObject"/> has not been spawned yet. you can try getting the reference at a later point in time.</returns>
+        public bool TryGet(out NetworkBehaviour networkBehaviour, NetworkManager networkManager = null)
+        {
+            networkBehaviour = GetInternal(this, null);
+            return networkBehaviour != null;
+        }
+
+        /// <summary>
+        /// Tries to get the <see cref="NetworkBehaviour"/> referenced by this reference.
+        /// </summary>
+        /// <param name="networkBehaviour">The <see cref="NetworkBehaviour"/> which was found. Null if the corresponding <see cref="NetworkObject"/> was not found.</param>
+        /// <param name="networkManager">The networkmanager. Uses <see cref="NetworkManager.Singleton"/> to resolve if null.</param>
+        /// <typeparam name="T">The type of the networkBehaviour for convenience.</typeparam>
+        /// <returns>True if the <see cref="NetworkBehaviour"/> was found; False if the <see cref="NetworkBehaviour"/> was not found. This can happen if the corresponding <see cref="NetworkObject"/> has not been spawned yet. you can try getting the reference at a later point in time.</returns>
+        public bool TryGet<T>(out T networkBehaviour, NetworkManager networkManager = null) where T : NetworkBehaviour
+        {
+            networkBehaviour = (T)GetInternal(this, null);
+            return networkBehaviour != null;
+        }
+
+        /// <inheritdoc/>
+        public void NetworkSerialize(NetworkSerializer serializer)
+        {
+            m_NetworkObjectReference.NetworkSerialize(serializer);
+            serializer.Serialize(ref m_NetworkBehaviourId);
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        private static NetworkBehaviour GetInternal(NetworkBehaviourReference networkBehaviourRef, NetworkManager networkManager = null)
+        {
+            if (networkBehaviourRef.m_NetworkObjectReference.TryGet(out NetworkObject networkObject, networkManager))
+            {
+                return networkObject.GetNetworkBehaviourAtOrderIndex(networkBehaviourRef.m_NetworkBehaviourId);
+            }
+
+            return null;
+        }
+
+        /// <inheritdoc/>
+        public bool Equals(NetworkBehaviourReference other)
+        {
+            return m_NetworkObjectReference.Equals(other.m_NetworkObjectReference) && m_NetworkBehaviourId == other.m_NetworkBehaviourId;
+        }
+
+        /// <inheritdoc/>
+        public override bool Equals(object obj)
+        {
+            return obj is NetworkBehaviourReference other && Equals(other);
+        }
+
+        /// <inheritdoc/>
+        public override int GetHashCode()
+        {
+            unchecked
+            {
+                return (m_NetworkObjectReference.GetHashCode() * 397) ^ m_NetworkBehaviourId.GetHashCode();
+            }
+        }
+
+        public static implicit operator NetworkBehaviour(NetworkBehaviourReference networkBehaviourRef) => GetInternal(networkBehaviourRef);
+
+        public static implicit operator NetworkBehaviourReference(NetworkBehaviour networkBehaviour) => new NetworkBehaviourReference(networkBehaviour);
+    }
+}

com.unity.netcode.gameobjects/Runtime/Serialization/NetworkObjectReference.cs

@@ -0,0 +1,131 @@
+using System;
+using System.Runtime.CompilerServices;
+using UnityEngine;
+
+namespace Unity.Netcode
+{
+    /// <summary>
+    /// A helper struct for serializing <see cref="NetworkObject"/>s over the network. Can be used in RPCs and <see cref="NetworkVariable{T}"/>.
+    /// </summary>
+    public struct NetworkObjectReference : INetworkSerializable, IEquatable<NetworkObjectReference>
+    {
+        private ulong m_NetworkObjectId;
+
+        /// <summary>
+        /// The <see cref="NetworkObject.NetworkObjectId"/> of the referenced <see cref="NetworkObject"/>.
+        /// </summary>
+        public ulong NetworkObjectId
+        {
+            get => m_NetworkObjectId;
+            internal set => m_NetworkObjectId = value;
+        }
+
+        /// <summary>
+        /// Creates a new instance of the <see cref="NetworkObjectReference"/> struct.
+        /// </summary>
+        /// <param name="networkObject">The <see cref="NetworkObject"/> to reference.</param>
+        /// <exception cref="ArgumentNullException"></exception>
+        /// <exception cref="ArgumentException"></exception>
+        public NetworkObjectReference(NetworkObject networkObject)
+        {
+            if (networkObject == null)
+            {
+                throw new ArgumentNullException(nameof(networkObject));
+            }
+
+            if (networkObject.IsSpawned == false)
+            {
+                throw new ArgumentException($"{nameof(NetworkObjectReference)} can only be created from spawned {nameof(NetworkObject)}s.");
+            }
+
+            m_NetworkObjectId = networkObject.NetworkObjectId;
+        }
+
+        /// <summary>
+        /// Creates a new instance of the <see cref="NetworkObjectReference"/> struct.
+        /// </summary>
+        /// <param name="gameObject">The GameObject from which the <see cref="NetworkObject"/> component will be referenced.</param>
+        /// <exception cref="ArgumentNullException"></exception>
+        /// <exception cref="ArgumentException"></exception>
+        public NetworkObjectReference(GameObject gameObject)
+        {
+            if (gameObject == null)
+            {
+                throw new ArgumentNullException(nameof(gameObject));
+            }
+
+            var networkObject = gameObject.GetComponent<NetworkObject>();
+
+            if (networkObject == null)
+            {
+                throw new ArgumentException($"Cannot create {nameof(NetworkObjectReference)} from {nameof(GameObject)} without a {nameof(NetworkObject)} component.");
+            }
+
+            if (networkObject.IsSpawned == false)
+            {
+                throw new ArgumentException($"{nameof(NetworkObjectReference)} can only be created from spawned {nameof(NetworkObject)}s.");
+            }
+
+            m_NetworkObjectId = networkObject.NetworkObjectId;
+        }
+
+        /// <summary>
+        /// Tries to get the <see cref="NetworkObject"/> referenced by this reference.
+        /// </summary>
+        /// <param name="networkObject">The <see cref="NetworkObject"/> which was found. Null if no object was found.</param>
+        /// <param name="networkManager">The networkmanager. Uses <see cref="NetworkManager.Singleton"/> to resolve if null.</param>
+        /// <returns>True if the <see cref="NetworkObject"/> was found; False if the <see cref="NetworkObject"/> was not found. This can happen if the <see cref="NetworkObject"/> has not been spawned yet. you can try getting the reference at a later point in time.</returns>
+        public bool TryGet(out NetworkObject networkObject, NetworkManager networkManager = null)
+        {
+            networkObject = Resolve(this, networkManager);
+            return networkObject != null;
+        }
+
+        /// <inheritdoc/>
+        public void NetworkSerialize(NetworkSerializer serializer)
+        {
+            serializer.Serialize(ref m_NetworkObjectId);
+        }
+
+        /// <summary>
+        /// Resolves the corresponding <see cref="NetworkObject"/> for this reference.
+        /// </summary>
+        /// <param name="networkObjectRef">The reference.</param>
+        /// <param name="networkManager">The networkmanager. Uses <see cref="NetworkManager.Singleton"/> to resolve if null.</param>
+        /// <returns>The resolves <see cref="NetworkObject"/>. Returns null if the networkobject was not found</returns>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        private static NetworkObject Resolve(NetworkObjectReference networkObjectRef, NetworkManager networkManager = null)
+        {
+            networkManager = networkManager != null ? networkManager : NetworkManager.Singleton;
+            networkManager.SpawnManager.SpawnedObjects.TryGetValue(networkObjectRef.m_NetworkObjectId, out NetworkObject networkObject);
+
+            return networkObject;
+        }
+
+        /// <inheritdoc/>
+        public bool Equals(NetworkObjectReference other)
+        {
+            return m_NetworkObjectId == other.m_NetworkObjectId;
+        }
+
+        /// <inheritdoc/>
+        public override bool Equals(object obj)
+        {
+            return obj is NetworkObjectReference other && Equals(other);
+        }
+
+        /// <inheritdoc/>
+        public override int GetHashCode()
+        {
+            return m_NetworkObjectId.GetHashCode();
+        }
+
+        public static implicit operator NetworkObject(NetworkObjectReference networkObjectRef) => Resolve(networkObjectRef);
+
+        public static implicit operator NetworkObjectReference(NetworkObject networkObject) => new NetworkObjectReference(networkObject);
+
+        public static implicit operator GameObject(NetworkObjectReference networkObjectRef) => Resolve(networkObjectRef).gameObject;
+
+        public static implicit operator NetworkObjectReference(GameObject gameObject) => new NetworkObjectReference(gameObject);
+    }
+}