Unfolding: how to get pixel coordinates from Marker?

Hi I have a path made by some data related to a bicycle root. I would like to have the path in pixel coordinates, I'm trying something like this:

List<Marker> myMarker;
myMarker = map.getMarkerManager(0).getMarkers();
for (int i = 0; i < myMarker.size(); i++) {
  println(map.getScreenPosition(myMarker.get(i).getLocation()));
}

But it returns very weird pixel coordinates, like

[ 0.0, 0.0, 0.0 ]
[ -8063.0, 195758.0, 0.0 ]
[ 0.0, 0.0, 0.0 ]
[ -10058.0, 247856.0, 0.0 ]
[ 0.0, 0.0, 0.0 ]

What would be the correct method to do so?