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Question "[MLAPI] Var data read too far. 1 bytes." When spawning client player prefab

Discussion in 'Netcode for GameObjects' started by dustyh55, Apr 11, 2021.

  1. dustyh55

    dustyh55

    Joined:
    Dec 10, 2013
    Posts:
    3
    When joining a server, the client will spawn the player prefab from other players, but will not spawn it's own prefab.

    I get

    [MLAPI] Var data read too far. 1 bytes.

    [MLAPI] Var data read too little. 15 bytes.

    [MLAPI] Failed to create object locally. [PrefabHash=0]. Hash could not be found. Is the prefab registered?

    So it seems the data stream is getting messed up somehow, but how? I tested a simpler player prefab and it spawned fine, what cold I have possibly done to the prefab to get this kind of behaviour?

    Full errors:


    [MLAPI] Var data read too far. 1 bytes.
    UnityEngine.Debug:LogWarning(Object)
    MLAPI.Logging.NetworkLog:LogWarning(String)
    MLAPI.NetworkedBehaviour:SetNetworkedVarData(List`1, Stream)
    MLAPI.NetworkedObject:SetNetworkedVarData(Stream)
    MLAPI.Spawning.SpawnManager:SpawnNetworkedObjectLocally(NetworkedObject, UInt64, Boolean, Boolean, Nullable`1, Stream, Boolean, Int32, Boolean, Boolean)
    MLAPI.Messaging.InternalMessageHandler:<HandleConnectionApproved>g__DelayedSpawnAction|4_0(Stream)
    MLAPI.Messaging.InternalMessageHandler:HandleConnectionApproved(UInt64, Stream, Single)
    MLAPI.NetworkingManager:HandleIncomingData(UInt64, String, ArraySegment`1, Single, Boolean)
    MLAPI.NetworkingManager:HandleRawTransportPoll(NetEventType, UInt64, String, ArraySegment`1, Single)
    MLAPI.NetworkingManager:Update()


    [MLAPI] Var data read too little. 15 bytes.
    UnityEngine.Debug:LogWarning(Object)
    MLAPI.Logging.NetworkLog:LogWarning(String)
    MLAPI.NetworkedBehaviour:SetNetworkedVarData(List`1, Stream)
    MLAPI.NetworkedObject:SetNetworkedVarData(Stream)
    MLAPI.Spawning.SpawnManager:SpawnNetworkedObjectLocally(NetworkedObject, UInt64, Boolean, Boolean, Nullable`1, Stream, Boolean, Int32, Boolean, Boolean)
    MLAPI.Messaging.InternalMessageHandler:<HandleConnectionApproved>g__DelayedSpawnAction|4_0(Stream)
    MLAPI.Messaging.InternalMessageHandler:HandleConnectionApproved(UInt64, Stream, Single)
    MLAPI.NetworkingManager:HandleIncomingData(UInt64, String, ArraySegment`1, Single, Boolean)
    MLAPI.NetworkingManager:HandleRawTransportPoll(NetEventType, UInt64, String, ArraySegment`1, Single)
    MLAPI.NetworkingManager:Update()


    [MLAPI] Failed to create object locally. [PrefabHash=0]. Hash could not be found. Is the prefab registered?
    UnityEngine.Debug:LogError(Object)
    MLAPI.Logging.NetworkLog:LogError(String)
    MLAPI.Spawning.SpawnManager:CreateLocalNetworkedObject(Boolean, UInt64, UInt64, Nullable`1, Nullable`1, Nullable`1)
    MLAPI.Messaging.InternalMessageHandler:<HandleConnectionApproved>g__DelayedSpawnAction|4_0(Stream)
    MLAPI.Messaging.InternalMessageHandler:HandleConnectionApproved(UInt64, Stream, Single)
    MLAPI.NetworkingManager:HandleIncomingData(UInt64, String, ArraySegment`1, Single, Boolean)
    MLAPI.NetworkingManager:HandleRawTransportPoll(NetEventType, UInt64, String, ArraySegment`1, Single)
    MLAPI.NetworkingManager:Update()
     
  2. luke-unity

    luke-unity

    Joined:
    Sep 30, 2020
    Posts:
    306
    How many and what type of NetworkVariables do you have on your player prefab? If you are using a custom INetworkSerialiazable that could be causing issues like that if there is a mistake in your serialization code.

    Besides that the only thing which comes to mind which could be causing this is a rare race condition we found which corrupts the data stream on the client while deserializing.
     
    dustyh55 likes this.
  3. dustyh55

    dustyh55

    Joined:
    Dec 10, 2013
    Posts:
    3
    Thank for the reply!

    Turns out I had make some NetworkedArrays of a custom INetworkSerialiazable class for testing purposes and removing those fixed the problem. It's weird though because the problem started happening long after I had created them (an update maybe?), anyway it's fixed, thanks for the suggestions.