Discussion About Mouse/document Relationship

it seems that the only way to get access to mouse position is via predefined events: mouseover, etc, where the mouse-position/object-beneath-mouse is stored in some properties of the event object such as clientX/target;

these properties are only accessible to me, the web developer, via the event object generated for the event;

so the problem is: what happens if none of the pre-defined events suit me?

specifically - all of the pre-defined events depend on user interaction: onmousemove, onfocus, onscroll, etc;

so if I do not have a user-interaction at some moment but yet still need mouse-position/object-beneath-mouse information I am out of luck ...

UNLESS I know how the event objects gather that info themselves;

for instance, onmouseover -- how does some <div> know that the mouse just moved over it?

I presume that on some internal clock scale, a time_A_mouse_pos is compared to a time_B_mouse_pos; and furthermore all objects in the document are queried at each time_N until some object says "hey, browser, I am located at that position";

so I would like to know how to access this internal communication between the mouse and the document that apparently the 'event' object accesses whenever an event is generated;