Mouse Direction In Minecraft

[Quad]

I was wondering how to keep my mouse pointed in a certain direction in a game like minecraft that uses 3 axis instead of just X and Y that the command MouseMove uses. When I try to use the MouseMove with 0, 0, it just points up at the sky. I was wondering how to -instead of pointing up- point in one direction where I can add in a loop to have it constantly correct itself, over and over. If anybody could help me with this, that would be great!