LocalAuthority

Introduction

Unity does not allow sending [Command] or [ClientRpc] methods from non player-controlled game objects. Local Authority makes this possible.

It is perfect for interactive games where objects, rather than a character, are being controlled.

Furthermore, multiplayer games must have client-side prediction, entity interpolation, and server reconciliation to be responsive and enjoyable. These features are not built-in to Unity. I'm experimenting with adding them to Local Authority. Currently, I have basic client-side prediction working.

See Gabriel Gambetta's blog series for an excellent overview of client-server game architecture.

This project is still under active development

Features

• Send a Command or RPC method from any game object, not just the player.
  • Decouple your code and improve readability!
  • The server is still authoritative (all Command/RPCs pass through it) so cheating may be prevented.
• Attribute based, just like UNet. Tack [MessageRpc] or [MessageCommand] above your method and you're done!
  • Invoke it with SendCallback(nameof(MyMethod)).
• Client-side prediction is built-in, so you can enjoy a responsive game for no extra work!
  • Enable it in the attribute: [MessageRpc(ClientSidePrediction = true)].

Examples

Example code is available in the Assets/Scripts/Examples/ folder. The Offline and Online scenes use the sample code.

Here's a snippet to show the power of Local Authority:

public class PlayingCard : LocalAuthorityBehaviour
{
    public Sprite frontImage;
    public Sprite backImage;
    public bool isShowingFront;

    public void OnMouseOver()
    {
        if (Input.GetButtonDown("Jump")
        {
            SendCallback(nameof(RpcFlipOver)); // Invoke the Rpc on all clients.
        }
    }

    [MessageRpc(ClientSidePrediction = true)] // Make this method an Rpc and enable client-side prediction.
    public void RpcFlipOver()
    {
        var imageToShow = isShowingFront ? frontImage : backImage;
        var spriteRenderer = GetComponent<SpriteRenderer>();
        spriteRenderer.sprite = imageToShow;
        isShowingFront = !isShowingFront;
    }
}