Well, I've been doing some research lately. Back in January I wrote up a a blog post titled "It's been 10 years since PaRappa - now what?". I was exploring the mainstream music games. Little did I know that these games are all part of the group known as "Rhythm" games. Of course, many folks know what a rhythm game is, and I do too.

What I DIDN'T know is that Rhythm games are just one of a handful of different types of music games. Rhythm games can include any games that play a soundtrack and must press buttons in time to the game. Examples include "Dance Dance Revolution", "Guitar Hero", "Rock Band", and "PaRappa the Rapper".

"Pitch" games recognize the pitch of your voice from a microphone, and like Rhythm games, you must keep time with the music, but instead using the pitch of your voice to sing along. "Karaoke Revolution"is one note-able example. "Volume" games include games like "Mad Maestro" and the upcoming "Wii Music". In these games you can control the volume of the music in the game through various means, thereby influencing the game play.

Next are "Eidetic" music games. These games will play a musical sequence, and it's up to the player to repeat the sequence back. In this regard, "Simon" is the oldest music game around.

To be short and sweet, I'll lump "Free Form" and "Generative" music games together. In both of these game types, the player and the elements of the game come together to create a unique sound track. It seems that creativity is more likely in the "Free Form" music game.

The last genre, and the one I'm most interested in, is the "Reactive" genre. Here, a pre-composed soundtrack plays, and in game elements can react to the volume, frequency patterns, and beats in the music. All of these genres, with the exception of the Rhythm game, are hard to come up with examples for.

That said, there are a handful of Reactive music games that I'm aware of. The first was published in February 2008 and created by an outfit called "Invisible Handlebar" and available from Valve software's Steam game portal. In this game, called AudioSurf, you move a race car left and right over a racetrack. The goal is to collect blocks that appear on the road, and stack them in groups of 3 to get points. You load in your own MP3, and the background environment animates in time with the music. The track itself dips and rises in time with the music as well. Supposedly, the blocks you collect also appear in time with the music as well - however they appear on the road far in advance and far in the distance of when you collect them. As a result the gameplay doesn't really feel in synch with the soundtrack. It's only if you really pay attention to your surroundings, and not to the game play to really get that connection. For example, a hip-hop track by "Jurassic 5" is a little more bouncy than a rock track by "Living Colour", but it can get hard to tell in gameplay the difference between the songs.

There are a few Adobe Flash examples of this like "Rhythm Night", but the game play isn't all that great. Most of the Flash examples to date are either Rhythm games, Eidetic, or just general music lesson games.

Fortunately there is an excellent example to draw from - and that's "Pteranodon" by an independent game developer from Sweden known as Nifflas. His name is Nicklas Nygren, and "Pteranodon" is a classic side-scrolling space shoot-em up game. The twist of course, is that the enemies appear on screen and fire at your in time with the music. Its a pretty simple game by today's standards - though the connection between what's on screen and the timing of the music makes me giddy. Apparently he composes his own music, so it's no surprise that "Pteranodon" just features one track, but one can just imagine where you can go from there.