Can AutoIt restore a scrollbar position? (in general; not talking GUI)

[Guy_]

Let's say a script has to do something that may or may not shift the page a fair bit in a general DTP program, browser, ...

In other words, the scrollbar was moved.

(1) Can the original scrollbar position be saved and restored?
I can think of a rough workaround or two, but I mean, more precisely...?

(2) If so, is it for example a different control for every program?

(3) Let's say for a workaround you might use the help of ...

MouseWheel ( "direction" [, clicks = 1] )

Is there an absolute relationship of clicks to pixels?
Or does the amount of scroll from these 'clicks' depend on how much movement was defined for the scroll wheel in Windows or Mouse driver software?

Thank You