public static int CompareTripple(SurfaceTripple a, SurfaceTripple b)
 {
     if (a.D < b.D)
     {
         return -1;
     }
     else if (a.D > b.D)
     {
         return 1;
     }
     else
     {
         if (a.V < b.V)
         {
             return -1;
         }
         else if (a.V > b.V)
         {
             return 1;
         }
         else
         {
             return 0;
         }
     }
 }
 public static int CompareTripple(SurfaceTripple a, SurfaceTripple b)
 {
     if (a.D < b.D)
     {
         return(-1);
     }
     else if (a.D > b.D)
     {
         return(1);
     }
     else
     {
         if (a.V < b.V)
         {
             return(-1);
         }
         else if (a.V > b.V)
         {
             return(1);
         }
         else
         {
             return(0);
         }
     }
 }