Get element at point in entire page (even if it's not visible)
<p>I have a page and on it are some widgets.  There are 2 columns.  Widgets will auto-resize themselves if there is no widget to their left (or right).</p>

<p>I'm using <a href="https://developer.mozilla.org/En/DOM%3adocument.elementFromPoint" rel="nofollow"><code>document.elementFromPoint</code></a> (after getting the widget's offset) to detect if there is a widget next to it.</p>

<p>There is a problem with <code>document.elementFromPoint</code> though.</p>

<blockquote>
  <p>If the specified point is outside the visible bounds of the document... the result is <em>null</em>.</p>
</blockquote>

<p>It only works if the element is in the viewport.  How can I detect what element is at a certain position even if it's not visible?</p>

<p><strong>EDIT</strong>: Here's an example:</p>

<p><img src="http://i.stack.imgur.com/NLvSm.png" alt="Crappy Mockup"></p>

<p>The red line is the viewport, and the grey box (with the red writing) is Widget D's <em>original position</em> (the other Widget D is where it is when the page is done loading).  When the page loads, it checks Widgets B, C, and D.  It gets their offsets, and then uses <code>document.elementFromPoint</code> to see if Widget A is to their right.  If Widget A is to their right, the Widget is half width, if not it's full width.</p>

<p>Widget D is full width because <code>document.elementFromPoint</code> returns null because it's outside the viewport.  How can I detect that Widget A is to the right of Widget D even though it's outside the viewport?</p>
