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Discussion in 'Multiplayer' started by liortal, Jun 12, 2015.

  1. liortal

    liortal

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    Hi,

    With the HLAPI, without customizing any behaviour, all [SyncVars] are being synced and updated between all connected game clients (from Server -> Client).

    1. I'd like to understand when this sync takes place? are updates to syncvars batched ? (e.g: if i have 5 different objects whose SyncVars were updated, are these updates sent at the same time?)
    2. Also, is there any control over this process ? for example, can i use SyncVars, but call a method myself that will decide when to call the update that will send the changes to the server ?
     
  2. Indiefreaks

    Indiefreaks

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    Nov 12, 2012
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    I can't reply to point 1.
    However regarding point 2., here would be my best guess to how you may want to implement it.

    SyncVars are updated from Server => Client as you mentioned.
    Thus, you may have a Command method in the same NetworkBehaviour inherited class that would get called from within your client instance (using a [Client] attribute on an Update method for instance where you could tell whenever you want it to be changed.
    Client.Update() => Calls Command on Server => Server Command implementation changes SyncVar value => Server.SyncVar value is networked to the Client.SyncVar instance.

    I for instance used this mechanism to define for each of my players their Name.
    I have a PlayerNetworkBehaviour class which has a Nickname SyncVar string and a CmdSetNickname(string name) method.
    When the player sets his nickname using an input field I placed on an in game form, I simply call the CmdSetNickname method which will set the new nickname on the server and will be reflected locally.

    Hope it helps.
     
  3. liortal

    liortal

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    This simply explains how to update data using commands. But what if i have 5 different NetworkBehaviours each with his own SyncVars. Can i control how these are synced ? (E.g: sync them all together)
     
  4. chrismarch

    chrismarch

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    Jul 24, 2013
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    I've found that the quickest way to get the most accurate information about details like serialization timing is to point an assembly browser like ILSpy at C:\Program Files\Unity\Editor\Data\UnityExtensions\Unity\Networking\UnityEngine.Networking.dll and browse the decompiled code.
     
  5. liortal

    liortal

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    I have already looked at the internal code a few times. By the looks of it (although that code is not found in the UnityEngine.Networking.dll) is that SyncVars are promoted to properties (using the UNetWeaver), and when updated, they post the new data to be updated on the server.

    I didn't follow long enough to see WHEN the data is actually sent.
     
  6. seanr

    seanr

    Unity Technologies

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    When the server detects an object with a NetworkIdentity is dirty it sends an update packet to clients.

    The generated syncvar serialization code in the script assembly DLL in the Library folder if you want to see it.