public yuan waijieyuan(point a, point b)
{
yuan y = new yuan();
y.p = a;
y.R = banjing(y.p, b);
y.mianji = y.R * y.R * Math.PI;
return(y);
}
//计算内切圆
public yuan neiqie(point dian, point b, point c)
{
yuan y = new yuan();
y.p.X = dian.X;
y.p.Y = dian.Y;
y.R = PointToSegDist(zx(b, c), dian);
y.mianji = y.R * y.R * Math.PI;
return(y);
}
private void button2_Click(object sender, EventArgs e)
{
double[] mj = new double[bianshu];
double R2;
int min = 0;
yuan[] yan = new yuan[bianshu];
bool b = true;
point[] point1 = new point[points.Length + 3];
for (int q = 0; q < points.Length; q++)
{
point1[q].X = points[q].X;
point1[q].Y = points[q].Y;
}
point1[points.Length] = point1[0];//将第一个加到最后一个上面
point1[points.Length + 1] = point1[1];
point1[points.Length + 2] = point1[2];
for (int i = 0; i < points.Length; i++)
{
zhixian z1 = new zhixian();
z1 = wj.zx(wj.zx(point1[i], point1[i + 1]), wj.zx(point1[i + 1], point1[i + 2]), point1[i + 1], point1, point1[i + 1]);
zhixian z2 = new zhixian();
z2 = wj.zx(wj.zx(point1[i + 1], point1[i + 2]), wj.zx(point1[i + 2], point1[i + 3]), point1[i + 2], point1, point1[i + 2]);
yuan y = new yuan();
y = wj.neiqie(wj.jiaodian(z1, z2), point1[i], point1[i + 1]);
for (int n = 0; n < points.Length; n++)
{
R2 = wj.banjing(y.p, point1[n]);
if (y.R > R2)
{
b = false;
break;
}
else
{
b = true;
}
}
if (!b)
{
continue;
}
mj[i] = y.mianji;
yan[i] = y;
}
for (int j = 0; j < mj.Length; j++)
{
if (paidxu(chongpai(mj)) == mj[j])
{
min = j;
}
}
label1.Text = "外接圆的X坐标:" + yan[min].p.X + " " + "外接圆的Y坐标:" + yan[min].p.Y + " " + "外接圆的半径:" + yan[min].R;
Graphics gra = this.pictureBox1.CreateGraphics();
gra.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
Pen pen = new Pen(Color.Pink); //画笔颜色
gra.DrawEllipse(pen, (int)yan[min].p.X - (int)yan[min].R, (int)yan[min].p.Y - (int)yan[min].R, (int)yan[min].R * 2, (int)yan[min].R * 2); //画椭圆的方法，x坐标、y坐标、宽、高，如果是100，则半径为50
}