You could always normalize the new one after you are done... it will more than likely round to 1, 0, 0, but it is probably more math performance drain than you would want to really deal with every time you do this operation.

Try something like this: http://www.thehazymind.com/blog/xna-and-winforms/

Have you considered Quaternions? They eliminate the gimbal lock that you are experiencing (not being able to rotate correctly after two axis have been aligned through an initial rotation). XNA has a quaternion rotation and other quaternion maths built in, so you should be able to accomplish what you are looking for with a little Googling/Wikipedia ...

With our lovely market lately though, I don't think it would be an entirely terrible decision to allow Steam to distribute XNA for PC games. I'm sure someone in the business side of things already had this idea and thought it well through though, so if it hasn't happened yet it probably won't happen soon.

[quote user="Shawn Hargreaves"]I don't know.[/quote] !!!! The Shawn, but... you always know!?!?

You don't need them to be infinite, because they will get clipped at some point no matter what (clipping planes doing their jobs and all...) If you are talking about an effect similar to a skybox where it is "infinitely" far away, then you just need to set the zbuffer calculation to always behind when drawing the lines so they ...

Send it to me... I'll convert it to 3.0 in 20 minutes and submit it myself... OR you could just have Visual Studio convert it for you automatically and quit whining with everyone else about versions...

Why not do a dot product of the shadow direction and the normal and don't show the shadow where the dot comes up negative?

Why not just write one yourself. The way a semaphore works is not exactly rocket science, and anyone with as much CS background as it sounds like you have should not have any trouble implementing their own. Every CS I know was required to implement mutexes/semaphores as one of the projects they do for their Operating System classes, so you should ...

Is it just me, or are there a ridiculous amount of people who want to use XNA 2.0 still? I have seen this in lots of forums and from people in the #xna IRC as well. What is so hard about having XNA 3.0 auto upgrade your projects for you? I would really like to see some legitimate reasons for now updating to 3.0, because so far I have seen none ...