docs: function(i, a, d) {
  
        this.index = i;
        this.angle = a;
        this.distance = d;
     
        this.compare = function(p) {
           if (this.angle<p.angle)
              return -1;
           else if (this.angle>p.angle)
              return 1;
           else {
              if (this.distance<p.distance)
                 return -1;
              else if (this.distance>p.distance)
                 return 1;
           }
           return 0;
        }
     }