paper.pageToLocalPoint(p)

Transform the point p defined in the page coordinate system to the local coordinate system.

paper.on('blank:pointerup', function(evt) {
  var pagePoint = g.Point(evt.pageX, evt.pageY);
  var localPoint1 = this.pageToLocalPoint(pagePoint);
  // alternative method signature
  var localPoint2 = this.pageToLocalPoint(evt.pageX, evt.pageY);
  // Move the element to the point, where the user just clicks.
  element.position(localPoint1.x, localPoint1.y);
});