title: raphaeljs: drag and apply transformation to Paper.set()
body: <p>I started to play a little bit with raphaeljs, however I'm having a small problem when dragging and applying a transformation to a Paper.set()</p>
  
  <p>Here is my example: <a href="http://jsfiddle.net/PQZmp/2/" rel="nofollow">http://jsfiddle.net/PQZmp/2/</a></p>
  
  <p>1) Why is the drag event added only to the <code>marker</code> and not the <code>slider</code>?</p>
  
  <p>2) The transformation is supposed to be relative(i.e. <code>translate by</code> and not <code>translate to</code>), however if I drag the <code>marker</code> twice, the second dragging starts from the beginning and not from the end of the first.</p>
  
  <p><b>EDIT:</b>
  After the response of Zero, I created a new JSFiddle example: <a href="http://jsfiddle.net/9b9W3/1/" rel="nofollow">http://jsfiddle.net/9b9W3/1/</a></p>
  
  <p>1) It would be cool if <code>this</code> referenced the <code>set</code> instead of the first element of the set. Can't this be done with <code>dragger.apply(slider)</code>? I tried it, but only works on the first execution of the method (perhaps inside Raphael it is already being done but to the first element inside the <code>set</code> instead of the <code>set</code>)</p>
  
  <p>2) According to Raphael <a href="http://raphaeljs.com/reference.html#Element.transform" rel="nofollow">docs</a> the transformation should be relative to the object position (i.e. <code>translate by</code> and not <code>translate to</code>). But it is not what is happening according to the jsfiddle above (check both markers drag events). </p>
  
  <p>3) So <code>2)</code> above creates a third question. If a <code>transform("t30,0")</code> is a <code>translation by 30px horizontally</code>, how is the origin calculated? Based on <code>attr("x")</code> or <code>getBBox().x</code>?</p>