Book Image

Unity Multiplayer Games

By : Alan R. Stagner
Book Image

Unity Multiplayer Games

By: Alan R. Stagner

Overview of this book

Unity is a game development engine that is fully integrated with a complete set of intuitive tools and rapid workflows used to create interactive 3D content. Multiplayer games have long been a staple of video games, and online multiplayer games have seen an explosion in popularity in recent years. Unity provides a unique platform for independent developers to create the most in-demand multiplayer experiences, from relaxing social MMOs to adrenaline-pumping competitive shooters. A practical guide to writing a variety of online multiplayer games with the Unity game engine, using a multitude of networking middleware from player-hosted games to standalone dedicated servers to cloud multiplayer technology. You can create a wide variety of online games with the Unity 4 as well as Unity 3 Engine. You will learn all the skills needed to make any multiplayer game you can think of using this practical guide. We break down complex multiplayer games into basic components, for different kinds of games, whether they be large multi-user environments or small 8-player action games. You will get started by learning networking technologies for a variety of situations with a Pong game, and also host a game server and learn to connect to it.Then, we will show you how to structure your game logic to work in a multiplayer environment. We will cover how to implement client-side game logic for player-hosted games and server-side game logic for MMO-style games, as well as how to deal with network latency, unreliability, and security. You will then gain an understanding of the Photon Server while creating a star collector game; and later, the Player.IO by creating a multiplayer RTS prototype game. You will also learn using PubNub with Unity by creating a chatbox application. Unity Multiplayer Games will help you learn how to use the most popular networking middleware available for Unity, from peer-oriented setups to dedicated server technology.
Table of Contents (14 chapters)
Unity Multiplayer Games
About the Author
About the Reviewers

Implementing server authoritative movement

Now that we have our script structured the way we need, we can go ahead and implement the rest. First, we'll create a structure to hold move commands:

// represents a move command sent to the server
private struct move
  public float HorizontalAxis;
  public float VerticalAxis;
  public double Timestamp;

  public move( float horiz, float vert, double timestamp )
    this.HorizontalAxis = horiz;
    this.VerticalAxis = vert;
    this.Timestamp = timestamp;

On the server, we'll store a buffer of move states sent from the client. We'll also keep a reference to our Player script for the client and server:

// a history of move states sent from client to server
List<move> moveHistory = new List<move>();

// a reference to the Player script attached to the game object.
Player playerScript;

// get the Player component
void Start()
  playerScript = GetComponent<Player>();

Now, in FixedUpdate we'll grab the current move state...