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

Notes on hacking

There are some improvements which can be made here, in order to further protect it from exploits. For instance, the server now immediately runs a simulation step when the user sends input. One only needs to send input at a faster rate in order to exploit this system.

We can modify our server to process input at a fixed rate, perhaps via a queue of move commands which are processed one at a time in FixedUpdate. Care needs to be taken to ensure that the server doesn't fall behind when processing user input.

The server could also keep track of the last processed input message, and when a new message is received the server compares the timestamps, discarding the new message if the timestamps are too close together. This could also be potentially exploited if the user tampers with timestamp values sent with the message. You could impose a limit on timestamps, so they cannot be older than a threshold (say, a few seconds), and cannot be newer than the current time (which is physically...