Interview with Community Games Developers

We speak to the developers behind Microsoft's first batch of freely available community-developed Xbox 360 games. It's the revenge of bedroom coding!
Meet 'Walaber', developer of JellyCar, Brian Cable, responsible for Proximity HD, James Silva of The Dishwasher: Dead Samurai fame and Jeff Pobst and Michael Austin of Hidden Path Entertainment, creators of Culture.

What sort of technical restrictions are placed on XNA developers? Are there things you'd like to have done that the dev platform won't allow?
* Walaber: Well, the choice to go with C# brings with it some performance issues (particularly on the Xbox 360), which required me to do more optimization of my code than I would have initially expected, considering that the Xbox 360 is so powerful. Hopefully future versions of XNA will improve some of these performance issues.
* Brian: From what I hear, XNA is not quite as powerful as a graphics engine developed internally, but I'm just one person, not a company, and even if I spent several years perfecting a graphics engine the industry and XNA itself will likely have leaped ahead of me anyway, and I'd constantly be playing catch-up with my engine and not focusing on actually making games, which is much more fun and interesting to me anyway.
Also there's no achievements, leaderboard support, or the camera support, and I don't think you have full access to Xbox LIVE multiplayer either, but I haven't looked too much into that yet. Achievements are understandable, though, or else you'd have everyone spamming five second non-games and releasing them to the service giving whoever played them max achievements instantly anyway. But of course, I would like access to all of these features, which is why I would love to someday release the game through XBLA.
* James: C# does slightly underperform versus native code. Personally, I'd rather be coding in C#, because I'm a rotten C++ coder. If I were in charge of things, I would market XNA with the tagline "XNA: Giving Hope to Rotten Coders."
* Michael: There are some features (pointers, etc) turned off for security reasons, and while managed code can be convenient to use, it does run more slowly. For instance, every time you access a variable in an array, C# has to validate the index. In C++ there are no handrails, so you can shoot yourself in the foot, but it's generally faster. The nice thing is that more and more heavy lifting is done by the GPU, and so the impact of using a managed language is less than it has been in the past.

http://blogs.guardian.co.uk/games/ar..._part_one.html