is there an jargon permitting an component confine page wholly until hits tip browser?

basically i am looking accomplish something identical impact uses have map follow down page hunt law page nonetheless i'd rather have immediate rather have locate adult few seconds after scroll. i also don't wish only set position "fixed" since i wish confine until confine off page, wholly following spin "fixed" (and likewise, user after scrolls behind up, i wish map spin "unstuck" confine behind down page).

i suspect achieved concerned javascript (using "watch", etc) detects map circuitously tip page changes css values appropriately, nonetheless i anticipating multiple relative/absolute/fixed positioned divs obviated need javascript during all.

and impetus i'd really drop-in library (or jquery plugin, etc) does only i am looking such thing exists. off-the-shelf scripts exist this, i'd adore hear first-hand trust doing perplexing same thing.