Downloading and installing Box2D for Flash

You can download the latest version of Box2D for Flash either from the official site (http://www.box2dflash.org/download) or from the SourceForge project page (http://sourceforge.net/projects/box2dflash/).

Once you have downloaded the zipped package, extract the Box2D folder (you can find it inside the Source folder) into the same folder you are using for your project. The following is how your awesome game folder should look before you start coding:

You can see the Box2D folder, the FLA file that I am assuming has a document class called Main and therefore Main.as, which is the class we will work on.

I would suggest you work on a 640 x 480 Flash movie at 30 frames per second (fps). The document class should be called Main and the examples will look better if you use a dark stage background color, such as #333333. At least these are the settings I am using throughout the book. Obviously you can change them as you want, but in that case your final movies may look a bit different than the examples shown in the book.

Now let's import Box2D classes.