Example #1
0
        public static HashSet <uint> Search(this GeometricGraph graph, int n, float minLatitude, float minLongitude, float maxLatitude, float maxLongitude)
        {
            List <long> longList = HilbertCurve.HilbertDistances(System.Math.Max(minLatitude, -90f), System.Math.Max(minLongitude, -180f), System.Math.Min(maxLatitude, 90f), System.Math.Min(maxLongitude, 180f), (long)n);

            longList.Sort();
            HashSet <uint> uintSet = new HashSet <uint>();
            int            index   = 0;
            uint           vertex1 = 0;
            uint           vertex2 = graph.VertexCount - 1U;

            for (; index < longList.Count && vertex1 < graph.VertexCount; ++index)
            {
                long num1 = longList[index];
                long maxHilbert;
                for (maxHilbert = num1; index < longList.Count - 1 && longList[index + 1] <= maxHilbert + 1L; ++index)
                {
                    maxHilbert = longList[index + 1];
                }
                uint  vertex;
                int   count;
                float latitude;
                float longitude;
                if (num1 == maxHilbert)
                {
                    if (graph.Search(num1, n, vertex1, vertex2, out vertex, out count))
                    {
                        int num2 = count;
                        for (; count > 0; --count)
                        {
                            if (graph.GetVertex(vertex + (uint)(count - 1), out latitude, out longitude) && (double)minLatitude < (double)latitude && ((double)minLongitude < (double)longitude && (double)maxLatitude > (double)latitude) && (double)maxLongitude > (double)longitude)
                            {
                                uintSet.Add(vertex + (uint)(count - 1));
                            }
                        }
                        vertex1 = vertex + (uint)num2;
                    }
                }
                else if (graph.SearchRange(num1, maxHilbert, n, vertex1, vertex2, out vertex, out count))
                {
                    int num2 = count;
                    for (; count > 0; --count)
                    {
                        if (graph.GetVertex(vertex + (uint)(count - 1), out latitude, out longitude) && (double)minLatitude < (double)latitude && ((double)minLongitude < (double)longitude && (double)maxLatitude > (double)latitude) && (double)maxLongitude > (double)longitude)
                        {
                            uintSet.Add(vertex + (uint)(count - 1));
                        }
                    }
                    vertex1 = vertex + (uint)num2;
                }
            }
            return(uintSet);
        }