/// <summary>
 /// Computes the Euclidean distance (L2 metric) from a <see cref="Coordinate"/> to a <see cref="Geometry"/>.
 /// </summary>
 /// <param name="geom">The geometry</param>
 /// <param name="pt">The Point</param>
 /// <param name="ptDist">The <c>PointPairDistance</c></param>
 public static void ComputeDistance(Geometry geom, Coordinate pt, PointPairDistance ptDist)
 {
     if (geom is LineString)
     {
         ComputeDistance((LineString)geom, pt, ptDist);
     }
     else if (geom is Polygon)
     {
         ComputeDistance((Polygon)geom, pt, ptDist);
     }
     else if (geom is GeometryCollection)
     {
         var gc = (GeometryCollection)geom;
         for (int i = 0; i < gc.NumGeometries; i++)
         {
             var g = gc.GetGeometryN(i);
             ComputeDistance(g, pt, ptDist);
         }
     }
     else
     {
         // assume geom is Point
         ptDist.SetMinimum(geom.Coordinate, pt);
     }
 }
        /// <summary>
        /// Computes the Euclidean distance (L2 metric) from a <see cref="Coordinate"/> to a <see cref="LineString"/>.
        /// </summary>
        /// <param name="line">The <c>LineString</c></param>
        /// <param name="pt">The Point</param>
        /// <param name="ptDist">The <c>PointPairDistance</c></param>
        public static void ComputeDistance(LineString line, Coordinate pt, PointPairDistance ptDist)
        {
            var coords      = line.Coordinates;
            var tempSegment = new LineSegment();

            for (int i = 0; i < coords.Length - 1; i++)
            {
                tempSegment.SetCoordinates(coords[i], coords[i + 1]);
                // this is somewhat inefficient - could do better
                var closestPt = tempSegment.ClosestPoint(pt);
                ptDist.SetMinimum(closestPt, pt);
            }
        }
        /// <summary>
        /// Computes the Euclidean distance (L2 metric) from a <see cref="Coordinate"/> to a <see cref="LineSegment"/>.
        /// </summary>
        /// <param name="segment">The <c>LineSegment</c></param>
        /// <param name="pt">The Point</param>
        /// <param name="ptDist">The <c>PointPairDistance</c></param>
        public static void ComputeDistance(LineSegment segment, Coordinate pt, PointPairDistance ptDist)
        {
            var closestPt = segment.ClosestPoint(pt);

            ptDist.SetMinimum(closestPt, pt);
        }