/// <summary>
/// 计算赤平投影中，面投影圆弧的圆心（设定大圆圆心为600,600半径480，上半球投影）
/// </summary>
/// <param name="trend">面倾向</param>
/// <param name="dip">面倾角</param>
/// <returns>返回圆弧圆心点</returns>
public Circle CalArc(double trend, double dip)
{
TdPoint P1 = new TdPoint();
TdPoint P2 = new TdPoint();
TdPoint Ps = new TdPoint();
P1.X = (600 + 480 * Math.Sin((trend + 90) * 3.14 / 180));
P1.Y = (600 - 480 * Math.Cos((trend + 90) * 3.14 / 180));
P2.X = (600 + 480 * Math.Sin((trend - 90) * 3.14 / 180));
P2.Y = (600 - 480 * Math.Cos((trend - 90) * 3.14 / 180));
Ps.X = (600 + 480 * Math.Sin((trend + 180) * 3.14 / 180) * (1 - dip / 90.0));
Ps.Y = (600 - 480 * Math.Cos((trend + 180) * 3.14 / 180) * (1 - dip / 90.0));
TdLine l1 = CalMidLine(P1, Ps);
TdLine l2 = CalMidLine(P2, Ps);
TdPoint Pc = CalIPoint(l1, l2);
double dist = Distance(Pc, P1);
Circle c = new Circle();
c.X = Pc.X;
c.Y = Pc.Y;
c.R = dist;
return(c);
}
/// <summary>
/// 计算量直线交点
/// </summary>
/// <param name="L1">直线1</param>
/// <param name="L2">直线2</param>
/// <returns>返回交点</returns>
public TdPoint CalIPoint(TdLine L1, TdLine L2)
{
TdPoint p = new TdPoint();
if (L1.C == 1 && L2.C == 1)//两直线都有有斜率
{
p.X = (L1.B - L2.B) / (L2.A - L1.A);
p.Y = (L1.B * L2.A - L2.B * L1.A) / (L2.A - L1.A);
}
else
{
if (L1.C == 0)
{
p.X = -L1.B;
p.Y = L2.A * p.X + L2.B;
}
else
{
if (L2.C == 0)
{
p.X = -L2.B;
p.Y = L1.A * p.X + L1.B;
}
}
}
return(p);
}
/// <summary>
/// 计算中垂线参数
/// </summary>
/// <param name="P1">点1</param>
/// <param name="P2">点2</param>
/// <returns>返回中垂线参数</returns>
public TdLine CalMidLine(TdPoint P1, TdPoint P2)
{
TdLine line = new TdLine(); //返回的中垂线
TdLine L = new TdLine(); //两点所在直线
if (P1.X != P2.X)
{
L.A = (P2.Y - P1.Y) / (P2.X - P1.X);
L.C = 1;
L.B = P1.Y - L.A * P1.X;
}
else
{
L.A = 1;
L.C = 0;
L.B = -P1.X;
}
TdPoint MidPoint = new TdPoint();//两点的中点
MidPoint.X = (P2.X + P1.X) / 2;
MidPoint.Y = (P2.Y + P1.Y) / 2;
if (L.C == 1) //直线有斜率
{
if (L.A != 0) //斜率不为0
{
line.A = -1 / L.A;
line.B = MidPoint.Y - line.A * MidPoint.X;
line.C = 1;
}
else
{
line.C = 0;
line.A = 1;
line.B = -MidPoint.X;
}
}
else
{
line.C = 1;
line.A = 0;
line.B = MidPoint.Y;
}
return(line);
}
/// <summary>
/// 计算直线参数
/// </summary>
/// <param name="P1">点1</param>
/// <param name="P2">点2</param>
/// <returns>返回直线参数</returns>
public TdLine CalLine(TdPoint P1, TdPoint P2)
{
TdLine L = new TdLine();
if (P1.X != P2.X)
{
L.A = (P2.Y - P1.Y) / (P2.X - P1.X);
L.C = 1;
L.B = P1.Y - L.A * P1.X;
}
else
{
L.A = 1;
L.C = 0;
L.B = -P1.X;
}
return(L);
}
/// <summary>
/// 计算直线参数
/// </summary>
/// <param name="X1"></param>
/// <param name="Y1"></param>
/// <param name="X2"></param>
/// <param name="Y2"></param>
/// <returns>返回直线参数</returns>
public TdLine CalLine(float X1, float Y1, float X2, float Y2)
{
TdPoint P1 = new TdPoint(X1, Y1);
TdPoint P2 = new TdPoint(X2, Y2);
TdLine L = new TdLine();
if (P1.X != P2.X)
{
L.A = (P2.Y - P1.Y) / (P2.X - P1.X);
L.C = 1;
L.B = P1.Y - L.A * P1.X;
}
else
{
L.A = 1;
L.C = 0;
L.B = -P1.X;
}
return(L);
}
