code: function(pos) {
              var layers = this.getChildren(),
                  len = layers.length,
                  end = len - 1,
                  n, shape;
  
              for(n = end; n >= 0; n--) {
                  shape = layers[n].getIntersection(pos);
                  if (shape) {
                      return shape;
                  }
              }
  
              return null;
          }
docs: get visible intersection shape. This is the preferred
  method for determining if a point intersects a shape or not
  @method
  @memberof Kinetic.Stage.prototype
  @param {Object} pos
  @param {Number} pos.x
  @param {Number} pos.y
  @returns {Kinetic.Shape}