fix: spawn disabled in scene placed and network prefab registration

com.unity.netcode.gameobjects/CHANGELOG.md

@@ -14,6 +14,8 @@ Additional documentation and release notes are available at [Multiplayer Documen
 ### Changed
 
 
+
+
 ### Deprecated
 
 
@@ -22,6 +24,10 @@ Additional documentation and release notes are available at [Multiplayer Documen
 
 ### Fixed
 
+- Issue with not being able to spawn initially disabled in-scene placed objects. (#4093)
+- Issue with pre-instantiated network prefab instances being marked as in-scene placed. Now pre-instantiated network prefabs are dynamically spawned. (#4093)
+- Issue where a user could spawn runtime created `NetworkObject` that has a GlobalObjectIdHash of zero. These are not valid instances and will no longer be allowed to spawn. (#4093)
+
 
 ### Security
 

com.unity.netcode.gameobjects/Documentation~/basics/scenemanagement/inscene-placed-networkobjects.md

@@ -184,9 +184,13 @@ public class MyInSceneNetworkObjectBehaviour : NetworkBehaviour
 > [!NOTE]
 > You only need to enable the NetworkObject on the server-side to be able to respawn it. Netcode for GameObjects only enables a disabled in-scene placed NetworkObject on the client-side if the server-side spawns it. This **does not** apply to dynamically spawned `NetworkObjects`. Refer to [the object pooling page](../../advanced-topics/object-pooling.md) for an example of recycling dynamically spawned NetworkObjects.
 
+### Pre-disabled in-scene placed NetworkObjects
+
+To initialize an in-scene placed NetworkObject in a disabled state and spawn it later, set its GameObject to inactive in the Editor while the respective scene is open. Once a networked session begins, you can re-enable and spawn it at any time.
+
 ### Setting an in-scene placed NetworkObject to a despawned state when instantiating
 
-Since in-scene placed NetworkObjects are automatically spawned when their respective scene has finished loading during a network session, you might run into the scenario where you want it to start in a despawned state until a certain condition has been met. To do this, you need to add some additional code in the `OnNetworkSpawn` part of your NetworkBehaviour component:
+To programmatically disable an in-scene placed NetworkObject, add some additional code in the `OnNetworkSpawn` part of a NetworkBehaviour component:
 
 ```csharp
 using UnityEngine;

com.unity.netcode.gameobjects/Documentation~/components/core/networkobject.md

@@ -19,6 +19,32 @@ When spawning a NetworkObject, the `NetworkObject.GlobalObjectIdHash` value init
 
 You can use [NetworkBehaviours](networkbehaviour.md) to add your own custom Netcode logic to the associated NetworkObject.
 
+### What is a valid NetworkObject?
+
+There are two categories of NetworkObjects:
+* Dynamically instantiated
+* [In-scene placed](../../basics/scenemanagement/inscene-placed-networkobjects.md)
+
+The following provides the validity requirements for both types.
+
+#### Dynamically instantiated network prefabs
+
+Dynamically instantiated network prefabs must:
+
+* Be a valid [network prefab](./networkobject.md#network-prefabs) created within the Editor.
+* Be registered in a network prefab list that's assigned to your NetworkManager.
+
+#### In-scene placed network prefabs
+
+In-scene placed network prefabs must:
+
+* Be a valid network prefab instance within a scene.
+* Be a GameObject with a NetworkObject component created within the scene while in the Editor.
+
+### What is an invalid NetworkObject?
+
+GameObjects that have NetworkObject components added to them during runtime are **not supported** and will result in the NetworkObject's `GlobalObjectIdHash` being zero, which causes synchronization issues. In the event you make this mistake, a warning message will be logged and the NetworkObject won't be spawned.
+
 ### Component order
 
 The order of components on a networked GameObject matters. When adding netcode components to a GameObject, ensure that the NetworkObject component is ordered before any NetworkBehaviour components.

com.unity.netcode.gameobjects/Editor/InScenePlacedProcessor.cs

@@ -24,6 +24,12 @@
  log.AddInfo(scene.name, scene.handle);
  foreach (var networkObject in FindObjects.FromSceneByType<NetworkObject>(scene, true))
  {
+ // Trap for users just creating things during runtime where this will be zero.
+ if (networkObject.GlobalObjectIdHash == 0)
+ {
+ log.Warning(new Context(LogLevel.Developer, $"{nameof(NetworkObject)}'s GlobalObjectIdHash value is zero! Runtime creating of {nameof(NetworkObject)}s is not supported. Skipping processing.").AddNetworkObject(networkObject));
+ continue;
+ }
  if (networkObject.SceneOrigin.IsValid() && networkObject.SceneOrigin.handle != scene.handle)
  {
  log.Warning(new Context(LogLevel.Developer, $"{nameof(NetworkObject)}'s SceneOrigin doesn't match current scene being processed! Skipping processing.").AddInfo("SceneOrigin", networkObject.SceneOriginHandle).AddNetworkObject(networkObject));
@@ -36,7 +42,15 @@
  continue;
  }
 
+ // If already marked, the do nothing.
+ if (networkObject.InScenePlaced)
+ {
+ continue;
+ }
+
  networkObject.InScenePlaced = true;
+ // Will not be true when making a build and the values are serialized.
+ networkObject.InScenePlacedPostProcessorMarkedDuringRuntime = Application.isPlaying;
  }
  }
  }

com.unity.netcode.gameobjects/Runtime/Components/NetworkAnimator.cs

@@ -768,7 +768,7 @@ protected virtual void Awake()
  if (!m_Animator)
  {
 #if !UNITY_EDITOR
- Debug.LogError($"{nameof(NetworkAnimator)} {name} does not have an {nameof(UnityEngine.Animator)} assigned to it. The {nameof(NetworkAnimator)} will not initialize properly.");
+ Debug.LogWarning($"{nameof(NetworkAnimator)} {name} does not have an {nameof(UnityEngine.Animator)} assigned to it. The {nameof(NetworkAnimator)} will not initialize properly.");
 #endif
  return;
  }

com.unity.netcode.gameobjects/Runtime/Configuration/NetworkPrefabs.cs

@@ -47,22 +47,110 @@
  [NonSerialized]
  private List<NetworkPrefab> m_Prefabs = new List<NetworkPrefab>();
 
+ /// <summary>
+ /// Returns the last registered prefab.
+ /// </summary>
+ internal NetworkPrefab GetLastRegisteredPrefab()
+ {
+ if (m_Prefabs.Count == 0)
+ {
+ return null;
+ }
+ return m_Prefabs[m_Prefabs.Count - 1];
+ }
+
+ /// <summary>
+ /// Applies a network prefab at a specific index
+ /// </summary>
+ /// <param name="index">index to apply</param>
+ /// <param name="networkPrefab">network prefab to be applied</param>
+ /// <returns></returns>
+ internal bool AssignPrefabAtIndex(int index, NetworkPrefab networkPrefab)
+ {
+ if (index >= m_Prefabs.Count)
+ {
+ NetworkManager.Singleton.Log.Error(new Logging.Context(LogLevel.Normal, $"[{nameof(NetworkPrefabs)}][{nameof(AssignPrefabAtIndex)}] Cannot apply prefab to index {index} when the {nameof(m_Prefabs)} count is only {m_Prefabs.Count}!"));
+ return false;
+ }
+ m_Prefabs[index] = networkPrefab;
+ return true;
+ }
+
+ [NonSerialized]
+ private Dictionary<uint, NetworkPrefab> m_PrefabHashIds = new Dictionary<uint, NetworkPrefab>();
+
  [NonSerialized]
  private List<NetworkPrefab> m_RuntimeAddedPrefabs = new List<NetworkPrefab>();
 
- private void AddTriggeredByNetworkPrefabList(NetworkPrefab networkPrefab)
+ private bool InternalAddPrefab(NetworkPrefab networkPrefab)
  {
  if (AddPrefabRegistration(networkPrefab))
  {
  // Don't add this to m_RuntimeAddedPrefabs
  // This prefab is now in the PrefabList, so if we shutdown and initialize again, we'll pick it up from there.
  m_Prefabs.Add(networkPrefab);
+
+ // We are not getting all potential overrides but just determining if the prefab has been registered.
+ if (!m_PrefabHashIds.ContainsKey(networkPrefab.SourcePrefabGlobalObjectIdHash))
+ {
+ m_PrefabHashIds.Add(networkPrefab.SourcePrefabGlobalObjectIdHash, networkPrefab);
+ }
+ if (!m_PrefabHashIds.ContainsKey(networkPrefab.TargetPrefabGlobalObjectIdHash))
+ {
+ m_PrefabHashIds.Add(networkPrefab.TargetPrefabGlobalObjectIdHash, networkPrefab);
+ }
+ return true;
  }
+ return false;
  }
 
- private void RemoveTriggeredByNetworkPrefabList(NetworkPrefab networkPrefab)
+ private void InternalRemovePrefab(NetworkPrefab networkPrefab)
  {
  m_Prefabs.Remove(networkPrefab);
+ m_PrefabHashIds.Remove(networkPrefab.SourcePrefabGlobalObjectIdHash);
+ }
+
+ internal bool IsBasedOnRegisteredPrefab(NetworkObject networkObject)
+ {
+
+
+ return m_PrefabHashIds.ContainsKey(networkObject.GlobalObjectIdHash);
+ }
+
+ internal bool IsActualPrefabAsset(NetworkObject networkObject)
+ {
+ var isActualPrefabAsset = false;
+ if (m_PrefabHashIds.TryGetValue(networkObject.GlobalObjectIdHash, out NetworkPrefab networkPrefab))
+ {
+ switch (networkPrefab.Override)
+ {
+ case NetworkPrefabOverride.Prefab:
+ case NetworkPrefabOverride.None:
+ {
+ isActualPrefabAsset = networkPrefab.Prefab != null && networkObject.gameObject == networkPrefab.Prefab;
+ break;
+ }
+ case NetworkPrefabOverride.Hash:
+ {
+ isActualPrefabAsset = networkPrefab.SourceHashToOverride == networkObject.GlobalObjectIdHash;
+ break;
+ }
+ }
+ }
+ return isActualPrefabAsset;
+ }
+
+ private void AddTriggeredByNetworkPrefabList(NetworkPrefab networkPrefab)
+ {
+ // Don't add this to m_RuntimeAddedPrefabs
+ // This prefab is now in the PrefabList, so if we shutdown and initialize again, we'll pick it up from there.
+ InternalAddPrefab(networkPrefab);
+ // Log warning if this returns false?
+ }
+
+ private void RemoveTriggeredByNetworkPrefabList(NetworkPrefab networkPrefab)
+ {
+ InternalRemovePrefab(networkPrefab);
  }
 
  /// <summary>
@@ -93,6 +181,7 @@
  /// <param name="warnInvalid">When true, logs warnings about invalid prefabs that are removed during initialization</param>
  public void Initialize(bool warnInvalid = true)
  {
+ m_PrefabHashIds.Clear();
  m_Prefabs.Clear();
  NetworkPrefabsLists.RemoveAll(x => x == null);
  foreach (var list in NetworkPrefabsLists)
@@ -113,7 +202,7 @@
  prefabs.AddRange(list.PrefabList);
  }
  }
-
+ m_PrefabHashIds = new Dictionary<uint, NetworkPrefab>();
  m_Prefabs = new List<NetworkPrefab>();
 
  List<NetworkPrefab> removeList = null;
@@ -124,23 +213,15 @@
 
  foreach (var networkPrefab in prefabs)
  {
- if (AddPrefabRegistration(networkPrefab))
- {
- m_Prefabs.Add(networkPrefab);
- }
- else
+ if (!InternalAddPrefab(networkPrefab))
  {
  removeList?.Add(networkPrefab);
  }
  }
 
  foreach (var networkPrefab in m_RuntimeAddedPrefabs)
  {
- if (AddPrefabRegistration(networkPrefab))
- {
- m_Prefabs.Add(networkPrefab);
- }
- else
+ if (!InternalAddPrefab(networkPrefab))
  {
  removeList?.Add(networkPrefab);
  }
@@ -171,14 +252,12 @@
  /// </remarks>
  public bool Add(NetworkPrefab networkPrefab)
  {
- if (AddPrefabRegistration(networkPrefab))
+ var added = InternalAddPrefab(networkPrefab);
+ if (added)
  {
- m_Prefabs.Add(networkPrefab);
  m_RuntimeAddedPrefabs.Add(networkPrefab);
- return true;
  }
-
- return false;
+ return added;
  }
 
  /// <summary>
@@ -197,8 +276,7 @@
  {
  throw new ArgumentNullException(nameof(prefab));
  }
-
- m_Prefabs.Remove(prefab);
+ InternalRemovePrefab(prefab);
  m_RuntimeAddedPrefabs.Remove(prefab);
  OverrideToNetworkPrefab.Remove(prefab.TargetPrefabGlobalObjectIdHash);
  NetworkPrefabOverrideLinks.Remove(prefab.SourcePrefabGlobalObjectIdHash);
@@ -294,14 +372,12 @@
 
  uint source = networkPrefab.SourcePrefabGlobalObjectIdHash;
  uint target = networkPrefab.TargetPrefabGlobalObjectIdHash;
-
  // Make sure the prefab isn't already registered.
  if (NetworkPrefabOverrideLinks.ContainsKey(source))
  {
- var networkObject = networkPrefab.Prefab.GetComponent<NetworkObject>();
-
+ var nameOrHashOverride = networkPrefab.Override == NetworkPrefabOverride.Hash ? $"Hash: {networkPrefab.SourcePrefabGlobalObjectIdHash}" : networkPrefab.Prefab?.name;
  // This should never happen, but in the case it somehow does log an error and remove the duplicate entry
- Debug.LogError($"{nameof(NetworkPrefab)} ({networkObject.name}) has a duplicate {nameof(NetworkObject.GlobalObjectIdHash)} source entry value of: {source}!");
+ Debug.LogError($"{nameof(NetworkPrefab)} ({nameOrHashOverride}) has a duplicate {nameof(NetworkObject.GlobalObjectIdHash)} source entry value of: {source}!");
  return false;
  }