On Tuesday night I got the chance to conduct a hands-on session on building a physics based game in an hour. Okay it was more like an hour and half, but the Atlanta iPhone Dev meetup group were patient group. With MacBooks and Xcode ready, we started out.

First there was a tease of the full game, physics, art work, touch interaction, sound effects, music soundtrack, and even some particle system effects. Since you would just scroll down anyways, here is the final game:

I provided a game project file for the class, it had everything we would be using, so we could focus on what the code did and how it worked versus just trying to type/copy code from the Keynote slides. Most of the functionality was commented out or behind #ifdefs so we could look at each feature separate from the others.

In the beginning, there is nothing but physics and Box2d debug draw:

Pretty neat, but even the Atari had better graphics. Time to dive into how Cocos2d works and add some sprites to our game. While we are at it, some layers too (background, instructions). To top it off, we added some snow particle system and sounds.

I could not have asked for a better group of people to present to, they were very eager to learn, and we had a great time. The best moment for me was when we enabled sounds and from all over the room you started the hear the Penguin squeaks and snowball tosses.

I’m presenting on this topic at the 360idev Conference in San Jose (April 11-14), with some tweaks and extra features. It is an excellent conference, if you want to be a part of the iPhone developer community you can’t miss it! http://bit.ly/360conf