This wiki contains documentation about the Multiplayer API, the Emulator, and tutorials for creating multiplayer games in flash. This project main target audience is game developers that wish to create new multiplayer flash games, or to convert single-player flash games to multiplayer. Make sure you read the index page that contains general info, target audience, mailing lists and licensing comments.

Multiplayer API

The Multiplayer API is a set of APIs to develop multiplayer flash games. Each API is a set of functions in actionscript (AS) that communicate using LocalConnection with a container that should communicate these operations to a multiplayer server. The resulting game is a SWF file, written either in actionscript2 (AS2) or actionscript3 (AS3), published for flash version 8 or higher.

Multiplayer APIs

The Multiplayer API is composed of 2 APIs:

• ClientGameAPI - for developing multiplayer games.
• ConnectedGameAPI - for adding small multiplayer fetures to a single player game(not yet available).

You should write a class that extends one of the above APIs, and when your SWF is loaded, it should create one instance of that class.

The Multiplayer API Implementation describes the internal implementation that uses LocalConnection. The implementation details should not concern game developers, but they are important for websites hosting the games.

You may either test the games in the Emulator, or submit your game online to a gaming website that supports this API. One such website is Come2Play. Another distribution channel is Skype GameXN - in the near future we will write a container that translates this Multiplayer API to Skype GameXN platform.

AS2 vs AS3

Although AS2 and AS3 have major differences, we tried to abstract away these differences by hiding them behind a LocalConnection and using almost identical signatures for the class ClientGameAPI. The only difference in the signatures between the AS2 and AS3 versions, is that the type Number in AS2 was changed into int in AS3, and void to Void. The remainder of this wiki describes the AS3 version. We recommend using AS3 because it is more stable, fast, and easier to debug.

To learn more about these differences go to Online_vs_Emulator

Debugging and error handling in AS3

In "Publish Setting" you should select the option "Permit debugging". This will include the line number of the error in the stacktraces, e.g.

at MyAPI/sendDoOperation()[X:\Come2Play\API_GoogleCodeSVN\AS3\TestClientGameAPI\TestClientGameAPI.as:121]

Remember that the stack traces of an error are available only in the debugger version of the flash player (and not in the release version), see Error.getStackTrace(). Therefore you should run the Emulator and do online testing using the Adobe Flash Player Debugger.

trace() function

If your game is using the built-in trace() function, and you want to see the traces, then you should create a file mm.cfg in

C:\Documents and Settings\<USER_NAME>

The content of mm.cfg should be

ErrorReportingEnable=1
TraceOutputFileEnable=1

After creating this file, the traces should be written to

C:\Documents and Settings\<USER_NAME>\Application Data\Macromedia\Flash Player\Logs\flashlog.txt

See http://livedocs.adobe.com/flex/3/html/help.html?content=logging_04.html#196092 for more explanations.

FPS

Frame per seconds (FPS): Your game may run in any fps you may choose. We recommend using less than 40 fps to avoid overloading slow computers.

Keyboard and Mouse events

Note that the game and chat might be in the same window. which means you are going to get Keyboard and Mouse input, from your game and from the container of your game. this issues represents a serious problem in case of a keyboard event, and therefore we have created a special callback function you should use called gotKeyboardEvent to receive your keyboard input from.

in the case of mouse events, the problem is less serious and you can rely on listening to game mouse Events directly. but in case you use the mouse's absolute position in your calculations you should take your game position into account, This will be passed down to your game through the gotCustomInfo callback.

obfuscate

We suggest that you encrypt/obfuscate your code to make it difficult for users to crack or steal your code. There are many programs for that purpose; one of them is Amayeta (http://www.amayeta.com/).

Emulator

When developing your game, you should use the Emulator. After you finished testing in the emulator, you may submit the game to any company that endorses this multiplayer API. One such company is Come2Play.

Online testing vs the Emulator discusses the differences you may find between the emulator and the online version, and common pitfalls.

Creating multiplayer games

This section contains pseudo code examples describing the way you should use the API to communicate with the server, the pseudo code examples use real flash commands to make the code easier to read and use.

you will also find full game source code for you to learn and work on.

And after learning and understanding the API we offer a basic Template to work on

TicTacToe explains about the implementation of TicTacToe using ClientGameAPI.