docs: function(badComponent, goodComponent) {
          if (goodComponent.equals(badComponent)) {
              return "";
          }
          var resolution = this.getResolution();
          var maxX = this.MAX_PIXEL - this.translationParameters.x;
          var maxY = this.MAX_PIXEL - this.translationParameters.y;
          var x1 = (goodComponent.x - this.featureDx) / resolution + this.left;
          var y1 = this.top - goodComponent.y / resolution;
          var x2 = (badComponent.x - this.featureDx) / resolution + this.left;
          var y2 = this.top - badComponent.y / resolution;
          var k;
          if (x2 < -maxX || x2 > maxX) {
              k = (y2 - y1) / (x2 - x1);
              x2 = x2 < 0 ? -maxX : maxX;
              y2 = y1 + (x2 - x1) * k;
          }
          if (y2 < -maxY || y2 > maxY) {
              k = (x2 - x1) / (y2 - y1);
              y2 = y2 < 0 ? -maxY : maxY;
              x2 = x1 + (y2 - y1) * k;
          }
          return x2 + "," + y2;
      }