Sun Shafts

I have three question:

  1. How can i make the Unity’s sunshafts stop following the camera?

  2. Unity’s sunshafts are coming from everywhere, how can i make them come only from one direction?

  3. Is it possible to achieve this kind of sunshafts in Unity:
    If it’s possible, what is the best way to do it? Make your own script?

Take a look at this generator in the asset store, I think it produces exactly what you are looking for.