code: function(px) {
          var passes = true;
          if(this.pixelTolerance && this.px) {
              var dpx = Math.sqrt(
                  Math.pow(this.px.x - px.x, 2) +
                  Math.pow(this.px.y - px.y, 2)
              );
              if(dpx < this.pixelTolerance) {
                  passes = false;
              }
          }
          return passes;
      }
docs: Method: passesTolerance
  Determine whether the mouse move is within the optional pixel tolerance.
  
  Parameters:
  px - {<OpenLayers.Pixel>}
  
  Returns:
  {Boolean} The mouse move is within the pixel tolerance.