Xonotic: Quake 1 Game, or why a company should open source it's code

How does this provide a reason for a company open sourcing its code?

This looks more like q3a than q1. Interesting how they took the q1 engine this far. It looks like I would love the fast gameplay of this, I have to give it a try!

Not sure what this is about. But the game engine is Darkplaces. Xonotic is just a game that uses it.<p>What code are you referring to?