class 点面关系
{ static void Main(string[] args){ //Vector2D point1 = new Vector2D(39.909209536859834, 116.3225715637207);//inVector2D point1 = new Vector2D(39.901045, 116.415596);//outVector2D cPoint = new Vector2D(39.909209536859834, 116.3225715637207); Console.WriteLine("点是否在圆内:" + 点是否在圆内(cPoint, 8000, point1));Console.WriteLine("点是否在圆内:" + 点是否在圆内(cPoint, new Vector2D(39.901045, 116.415596), point1)); //Vector2D point2 = new Vector2D(39.924745, 116.379204);//inVector2D point2 = new Vector2D(39.928695, 116.546059);//outVector2D pointA = new Vector2D(39.913423004886866, 116.36890411376953);Vector2D pointB = new Vector2D(39.93450133090293, 116.38727188110351); Console.WriteLine("点是否在矩形内:" + 点是否在矩形内(pointA, pointB, point2)); Vector2D point3 = new Vector2D(39.957649, 116.376801);//in//Vector2D point3 = new Vector2D(39.919216, 116.2817);//outList<Vector2D> polygon = new List<Vector2D>();polygon.Add(new Vector2D(39.909209536859834, 116.3225715637207));polygon.Add(new Vector2D(39.95920953685983, 116.3725715637207));polygon.Add(new Vector2D(39.95920953685983, 116.42257156372072));polygon.Add(new Vector2D(39.909209536859834, 116.4725715637207));polygon.Add(new Vector2D(39.85920953685984, 116.42257156372072));polygon.Add(new Vector2D(39.85920953685984, 116.3725715637207)); Console.WriteLine("点是否在多边形内:" + 点是否在多边形内(point3, polygon));Console.ReadLine();
}/// <summary>
/// 点是否在圆内(在边上也认为在圆内)/// </summary>/// <param name="cPoint">圆心坐标</param>/// <param name="cRadius">圆半径</param>/// <param name="point">当前点</param>/// <returns></returns>public static bool 点是否在圆内(Vector2D cPoint, double cRadius, Vector2D point){ var d1 = Distance(cPoint.Lat, cPoint.Lon, point.Lat, point.Lon);double distance = Math.Sqrt(Math.Pow(Math.Abs(point.X - cPoint.X), 2) + Math.Pow(Math.Abs(point.Y - cPoint.Y), 2));return distance <= cRadius;}private static double Distance(double lon1, double lat1, double lon2, double lat2)
{ double R = 6378137; //地球半径lat1 = lat1 * Math.PI / 180.0;lat2 = lat2 * Math.PI / 180.0; double sa2 = Math.Sin((lat1 - lat2) / 2.0);double sb2 = Math.Sin(((lon1 - lon2) * Math.PI / 180.0) / 2.0);return 2 * R * Math.Asin(Math.Sqrt(sa2 * sa2 + Math.Cos(lat1) * Math.Cos(lat2) * sb2 * sb2));}/// <summary>
/// 点是否在圆内(在边上也认为在圆内)/// </summary>/// <param name="cPoint">圆心坐标</param>/// <param name="onPoint">圆边上坐标</param>/// <param name="point">当前点</param>/// <returns></returns>public static bool 点是否在圆内(Vector2D cPoint, Vector2D onPoint, Vector2D point){ double cRadius = Distance(cPoint.Lat, cPoint.Lon, onPoint.Lat, onPoint.Lon);double distance = Distance(cPoint.Lat, cPoint.Lon, point.Lat, point.Lon);return distance <= cRadius;}/// <summary>
/// 点是否在多边形内(在边上也认为在多边形内)/// </summary>/// <param name="point">当前点</param>/// <param name="polygon">多边形点</param>/// <returns></returns>public static bool 点是否在多边形内(Vector2D point, List<Vector2D> polygon){ var res = SMath.CalcPointPolygonRelation(point, polygon);return res != PointPolygonRelation.OutOfPolygon;}/// <summary>
/// 点是否在矩形内/// </summary>/// <param name="pointA">对角上点A</param>/// <param name="pointB">对角上点B</param>/// <param name="point">当前点</param>/// <returns></returns>public static bool 点是否在矩形内(Vector2D pointA, Vector2D pointB, Vector2D point){ List<Vector2D> polygon = new List<Vector2D>();polygon.Add(pointA);polygon.Add(new Vector2D(pointA.X, pointB.Y));polygon.Add(pointB); polygon.Add(new Vector2D(pointB.X, pointA.Y));var res = SMath.CalcPointPolygonRelation(point, polygon);return res != PointPolygonRelation.OutOfPolygon;}}
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public static PointPolygonRelation CalcPointPolygonRelation(double x, double y, IList polygon)
{ if(polygon.Count < 3) return PointPolygonRelation.OutOfPolygon;IVector start = (IVector)polygon[polygon.Count - 2];if(start == null) return PointPolygonRelation.OutOfPolygon;IVector middle = (IVector)polygon[polygon.Count - 1];IVector end;PointPolygonRelation result = PointPolygonRelation.OutOfPolygon;int num = 0;double minX, minY, maxX, maxY;for(int i = 0; i < polygon.Count; i++, start = middle, middle = end){ end = (IVector)polygon[i];//如果点刚好在顶点上，则直接返回if((x == start.X && y == start.Y) || (x == middle.X && y == middle.Y) || (x == end.X && y == end.Y)){ result = PointPolygonRelation.OnPolygonVertex;goto Return;}if(middle.X == end.X && middle.Y == end.Y){ continue;}minX = Math.Min(middle.X, end.X);maxX = Math.Max(middle.X, end.X);//如果X不落在最大X值和最小X值之间，则跳过if(x > maxX || x < minX) continue;minY = Math.Min(middle.Y, end.Y);
maxY = Math.Max(middle.Y, end.Y);//如果Y大于最大Y值则跳过，因为向上做射线不可能相交if(y > maxY) continue;if(minX == maxX)//需要判断相交的线段为Y轴平行线{ if(y > minY && y < maxY){ result = PointPolygonRelation.OnPolygonBorder;goto Return;}else if(y < minY)//如果在最小的Y之下，因为目标线段为Y轴平行线，所以记为1次{ num++;}}else{ double k = (middle.Y - end.Y) / (middle.X - end.X);double b = middle.Y - k * middle.X;double crossY = k * x + b;
if(crossY < y) continue;//如果交点小于y则跳过，因为我们是向上做射线
if(crossY == y)
{ result = PointPolygonRelation.OnPolygonBorder;goto Return;}if(x == maxX || x == minX)
{ if((start.X > middle.X && end.X < middle.X) || (start.X < middle.X && end.X > middle.X))num++;}else{ num++;}}}if(num % 2 != 0) result = PointPolygonRelation.InPolygon;
Return:return result;
}/// <summary>
/// 计算点和面的关系/// </summary>/// <param name="point"></param>/// <param name="polygon"></param>/// <returns></returns>public static PointPolygonRelation CalcPointPolygonRelation(IVector point, IList polygon){ return CalcPointPolygonRelation(point.X, point.Y, polygon);}
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public enum PointPolygonRelation
{ /// <summary>/// 点在面内/// </summary>InPolygon,/// <summary>/// 点在边上/// </summary>OnPolygonBorder,/// <summary>/// 点在面外/// </summary>OutOfPolygon,/// <summary>/// 点在面的拐点上/// </summary>OnPolygonVertex}