class 点面关系
{
static void Main(string[] args)
{
//Vector2D point1
= new Vector2D(39.909209536859834, 116.3225715637207);//in
Vector2D point1 =
new Vector2D(39.901045, 116.415596);//out
Vector2D 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);//in
Vector2D
point2 = new Vector2D(39.928695, 116.546059);//out
Vector2D 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);//out
List<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;
}
}
******************
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);
}
_____________
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
}
经纬度计算是否在圆形内，是否在矩形内，是否在多边形内方法,布布扣,bubuko.com
原文地址：http://www.cnblogs.com/xiaoan-one/p/3736329.html
