code: function (bounds) {
          bounds = this.adjustBounds(bounds);
          var res = this.getServerResolution();
          var x = Math.round((bounds.left - this.tileOrigin.lon) / (res * this.tileSize.w));
          var y = Math.round((bounds.bottom - this.tileOrigin.lat) / (res * this.tileSize.h));
          var z = this.getServerZoom();
          var path = this.serviceVersion + "/" + this.layername + "/" + z + "/" + x + "/" + y + "." + this.type; 
          var url = this.url;
          if (OpenLayers.Util.isArray(url)) {
              url = this.selectUrl(path, url);
          }
          return url + path;
      }
docs: Method: getURL
  
  Parameters:
  bounds - {<OpenLayers.Bounds>}
  
  Returns:
  {String} A string with the layer's url and parameters and also the
  passed-in bounds and appropriate tile size specified as
  parameters