PUBLIC MARKS with tags visibility & jQuery

jQuery.fracs determines some fractions for an HTML element (visible fraction, fraction of the viewport, ...) and also provides the coordinates of these areas. As a bonus there is a page outline feature as seen on the right.

jQuery.fracs determines the fraction of an HTML element that is currently in the viewport, as well as the fraction it takes of the complete viewport and the fraction of the area that might possibly be visible. It also provides the coordinates of the visible rectangle in document, element and viewport space. See the demo to get an impression of some of the features.