code: function() {
  
      var
        s = this.selection.selection,
        a = this.axes,
        first = s.first,
        second = s.second,
        x1, x2, y1, y2;
  
      x1 = a.x.p2d(s.first.x);
      x2 = a.x.p2d(s.second.x);
      y1 = a.y.p2d(s.first.y);
      y2 = a.y.p2d(s.second.y);
  
      return {
        x1 : Math.min(x1, x2),
        y1 : Math.min(y1, y2),
        x2 : Math.max(x1, x2),
        y2 : Math.max(y1, y2),
        xfirst : x1,
        xsecond : x2,
        yfirst : y1,
        ysecond : y2
      };
    }
docs: TODO This isn't used.  Maybe it belongs in the draw area and fire select event methods?