mtillmann/jquery-rect

intersects and intersection for DOM elements

#What does it do? Test if two elements intersect and optionally receive the a .css()-ready object with the intersecting rectangle's coordinates.

##basic intersect test simply returns whether the two elements intersect:

new $.rect($('#someElement')).intersects($('#otherElement')); 

##using intersection receive the intersecting rectangle from the two elements:

new $.rect($('#someElement')).intersection($('#otherElement'));

the intersection-method accepts a second parameter called type. Possible values are "box" and "rect"(default). "box" will return an object that represents a box (top, right, bottom, left), "rect" will return an object that represents a css-compatible rectangle (left, top, width, height). "portion" will return the intersection area as percent, 1 being fully covered, 0.5 being half etc

##Options there are three options that can be passed as the second argument:

###position Which jQuery method should be used to determine the element positions. Possible values are "offset" and "position"(default). See jQuery's docs.

###dimension Which jQuery method should be used to determine the element dimensions. Possible values are "css" and "outer"(default). "css" will use jQuery's css method with 'width' and 'height', "outer" will use outerWidth and outerHeight.

###withMargin Passed to outerWidth/outerHeight to include margin in calculation. Defaults to true.

new $.rect($('#someElement'),{
	position : 'position',
	dimension : 'outer',
	withMargin : true
});

Based on jQuery boilerplate and inspired by google's closure library