You work for me, Computer.

By Brandon Bloom


Shawn’s AppWeek post inspired me to write one too. AppWeek is our chance to be creators for a little while and it was a lot of fun. I didn’t set out to build something nearly as ambitious as “Super Avatar Sample Smashup EXTREME! – ‘Capture the Cat’ edition”, but I did get to take a swing at a game I’ve wanted to build for a while: Rock’em Sock’em Avatars Avatar Boxing. Avatars, being a new feature in this release, were an unwritten requirement for all of the AppWeek games. Between SASSECTCE, my game, and the many others, Avatars were chasing cats, beating each other up, play futuristic sports, falling off buildings, dancing in a cloud of gems, being launched from canons to save the world, and much more. All this excitement was almost too much for a bunch of exhausted engineers, but that’s what the beer was for during the game unveilings.

Here’s what the game looked like with the basic animations wired up. You’ll notice that the avatars have been hitting the gym. That’s because their arms were too short to reach each other! I added a little extra bulk because I was laughing too hard not to. I directly bound the game pad triggers to the shoulder and elbow joints and rigged up the chase camera sample to inspect my work. There wasn’t much game play yet, but it was already fun. That’s always a good sign.


Even with just one week, I decided to invest some time into debugging visualizations. That turned out to be a really great idea.


Then, I added some collision spheres for the heads, hands, and upper bodies. This was a hacky, trial and error process. Thankfully, C# compiles quickly.


At this point, I spent an entire day working on the physics. I wanted the avatars to bounce/wobble when they got hit, so I rigged up some complex spring systems. Things were starting to work, but I’m generally pretty bad at this sort of thing and my simulation routinely exploded. The avatars arms went shooting off into space and I was getting pretty frustrated. No screen shots of that chaos because I am embarrassed.

With half a day to go, I added the obligatory damage bars and some rudimentary hand-to-head collision detection.


I was feeling pretty good about the game, despite my physics failures, it was pretty fun anyway. I wondered down the hall to chat with Jace, who had just added sound effects to his game. His game was hilarious before, but the sound effects were priceless. I ejected the sound effect CD out of his machine, yoinked it, and took off running. An hour later (and 10 minutes after the deadline), my game had some sweet punch and miss sounds. I also made the avatars’ heads pop up when their damage bar was full, accompanied by an awesome zip-tie sound.


At our team happy hour, I’d like to think Avatar Boxing was a fan favorite. I certainly had fun making it! I hope everyone enjoys Avatar support in the new XNA Game Studio.

Imported Comments

Danny Tuppeny

I really wish you guys were releasing these games – they sound so funny and it would be great to see how you did some of the stuff with Avatars.

Brandon Bloom

As Shawn said: “We did an AppWeek shortly before shipping Game Studio 1.0, which produced minigames by Dean and Minjie, plus a bunch of stuff that was too unfinished or too much of an IP violation to release.”

Believe me, the code for my game isn’t remotely useful :–) Hacks upon kludges upon hacks galore. It would be a significant chunk of work to turn it into something educational. Even if it was interesting, it is technically not mine to release. It would be a conflict of interest to publish it on Xbox LIVE Indie Games, since I created it during the course of my job.

Since our games are only being seen by the team, many developers use copyrighted assets in the interest of time. Fair use allows us to show them at our happy hour, but someone would certainly come knocking if we released them. It is very expensive to clean that up because now you need to involve artists and rework the code for the new art (AppWeek games aren’t robust, art changes are breaking).

Everyone would love to share, but it isn’t universally practical. Luckily, several cool Avatar-centric samples were inspired by app week, so we will have something to share. I’ll also see about recording some videos of the IP-safe games…

Danny Tuppeny

No worries, it makes sense. I’m sure we’ll see more Avatar samples soon that aren’t hacked together we can learn from :-D


This looks like it could be turned into a real fun game. It’s too bad that we can’t buff our Avatars up like this =(

Brandon Bloom

Yeah, sadly it appears that scaling individual body parts is against the rules (which were unwritten when I did this project). I believe the motivation is for accommodating future avatar accessories which might look awful with unknown joint transforms. Don’t quote me on that :–)