Odds are they use the angular velocity or angular acceleration to model how far the sites displace when you turn. This will be a vector, so its simply a matter of seeding this variable in a random semi random fashion when you click the sites button
more complicated than sway but worth it in my opinion since sway will just mean people with high sensitivity mice will keep shooting people (like me)
more complicated than sway but worth it in my opinion since sway will just mean people with high sensitivity mice will keep shooting people (like me)