Motion Tracking Data into Animation Nodes Editor? I've created a simple motion track from video in the movie clip editor.  I can see the motion data in the graph view:



I've also created an empty from the motion data and when I hit playback I can see the empty moving in the 3D view.

The problem is that when I add the empty as an object to the Node Animation area and wire it to any other node, I never see the X/Y values change over time during playback.  Here's my current node layout:



(EDIT: I'm using the text node to view the value of the X coordinate in real time during the animation playback).  

I know that the motion data can be used in the Compositor layout using the Track Position Node, but I want to use the tracking data to animate an object in the 3d space and am assuming the Animation Node editor would be more appropriate. 

Is there any way of getting the empty's location data into the Animation Node editor or barring that, passing the Track Position output from the Compositor Node editor into the Animation Node editor?

UPTDATE:  As recommended by SergeL, here's is how to retrieve the tracker empty location data using Animation Nodes:
According to the documentation:


  Matrices from Matrix Input node are more reliable than transforms from Transforms Input node because of their different forms and because they are always up to date even during physics simulations or when constraints are used.


For instance, if one uses a Copy Location constraint to adjust the object's location, the transforms will report the original location while the matrix inputs will report the final location.