private Circle findSec(int n, MyPoint[] p, int m, MyPoint[] b)
{
Circle sec = new Circle();
// Compute the Smallest Enclosing Circle defined by B
if (m == 1)
{
sec = new Circle(b[0]);
}
else if (m == 2)
{
sec = new Circle(b[0], b[1]);
}
else if (m == 3)
{
return new Circle(b[0], b[1], b[2]);
}
// Check if all the MyMyPoints in p are enclosed
for (int i = 0; i < n; i++)
{
//if the MyMyPoint is outside the circle
if (sec.belongsToCircle(p[i]) == -1)
{
// Compute B <--- B union P[i].
b[m] = new MyPoint(p[i].getX(), p[i].getY());
// Recurse
sec = findSec(i, p, m + 1, b);
}
}
return sec;
}
public Circle(MyPoint p1, MyPoint p2, MyPoint p3)
{
try
{
double x = (p3.getX() * p3.getX() * (p1.getY() - p2.getY()) + (p1.getX() * p1.getX() + (p1.getY() - p2.getY()) * (p1.getY() - p3.getY()))
* (p2.getY() - p3.getY()) + p2.getX() * p2.getX() * (-p1.getY() + p3.getY()))
/ (2 * (p3.getX() * (p1.getY() - p2.getY()) + p1.getX() * (p2.getY() - p3.getY()) + p2.getX() * (-p1.getY() + p3.getY())));
double y = (p2.getY() + p3.getY()) / 2 - (p3.getX() - p2.getX()) / (p3.getY() - p2.getY()) * (x - (p2.getX() + p3.getX()) / 2);
Center = new MyPoint(x, y);
radius = Center.distance(p1);
}
catch (Exception e)
{
MessageBox.Show("Error creating circle with three MyPoints: " + e.ToString());
}
}
private void MainDrawingArea_MouseClick(object sender, MouseEventArgs e)
{
g.DrawArc(new Pen(Color.Red), (float)e.X, (float)e.Y, (float)4.0, (float)4.0, (float)0.0, (float)360.0);
p[n++] = new MyPoint(e.X, e.Y);
sec = findSec(n, p, 0, b);
using (System.IO.StreamWriter file = new System.IO.StreamWriter(@"Log.txt", true))
{
file.WriteLine("Num MyMyPoints: {0}", n);
for (int i = 0; i < n; i++)
{
string formatString = String.Format("Center {0} {1} MyPoint {2} {3} Radius: {4} Distance: {5}",
sec.getCenter().getX(), sec.getCenter().getY(), p[i].getX(), p[i].getY(), sec.getRadius(), sec.getCenter().distance(p[i]));
file.WriteLine(formatString);
}
file.WriteLine("");
}
if (n > 1)
{
try
{
MyPoint center = sec.getCenter();
int r = (int) sec.getRadius();
if (prev_height > 0)
{
g.DrawArc(new Pen(Color.White), (float)prev_x, (float)prev_y, (float)prev_width, (float)prev_height, 0, 360);
}
double x = center.getX() - r; prev_x = x;
double y = center.getY() - r; prev_y = y;
double width = 2 * r; prev_width = width;
int height = 2 * r; prev_height = height;
g.DrawArc(new Pen(Color.Blue), (float)x, (float)y, (float)width, (float)height, 0, 360);
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
}
}
public Circle(MyPoint first, MyPoint second)
{
Center = new MyPoint((first.getX() + second.getX()) / 2, (first.getY() + second.getY()) / 2);
radius = Center.distance(first);
}
public Circle(MyPoint Center)
{
this.Center = Center;
this.radius = 0;
}
// Construct a MyPoint with the same location as the specified MyPoint
public MyPoint(MyPoint MyPoint)
{
x = MyPoint.x;
y = MyPoint.y;
}
// Determine whether two MyPoints are equal
public bool equals(MyPoint MyPoint)
{
return (x == MyPoint.x) && (y == MyPoint.y);
}
// Calcualte the distance between two MyPoints
public double distance(MyPoint MyPoint)
{
double dx = x - MyPoint.x;
double dy = y - MyPoint.y;
return Math.Sqrt(dx * dx + dy * dy);
}
public Circle(MyPoint first, MyPoint second)
{
Center = new MyPoint((first.getX() + second.getX()) / 2, (first.getY() + second.getY()) / 2);
radius = Center.distance(first);
}
public Circle(MyPoint Center, double radius)
{
this.Center = Center;
this.radius = radius;
}
public Circle(MyPoint Center)
{
this.Center = Center;
this.radius = 0;
}
/* public static double GetDistance(MyPoint first, MyPoint second)
{
return Math.Sqrt((first.X - second.X) * (first.X - second.X) + (first.Y - second.Y) * (first.Y - second.Y));
}
*/
public Circle()
{
this.Center = new MyPoint(0, 0);
radius = 0;
}
// Calculate the middle MyPoint between two MyPoints
public MyPoint midMyPoint(MyPoint MyPoint)
{
return(new MyPoint((x + MyPoint.x) / 2, (y + MyPoint.y) / 2));
}
// Translate a MyPoint to the specified location
public void translate(MyPoint MyPoint)
{
translate(MyPoint.x, MyPoint.y);
}
// Translate a MyPoint to the specified location
public void translate(MyPoint MyPoint)
{
translate(MyPoint.x, MyPoint.y);
}
public int belongsToCircle(MyPoint other)
{
if ((Center.distance(other) - radius) < 0.000001) return 0;
if (Center.distance(other) > radius) return -1;
return 1;
}
// Construct a MyPoint with the same location as the specified MyPoint
public MyPoint(MyPoint MyPoint)
{
x = MyPoint.x;
y = MyPoint.y;
}
/* public static double GetDistance(MyPoint first, MyPoint second)
* {
* return Math.Sqrt((first.X - second.X) * (first.X - second.X) + (first.Y - second.Y) * (first.Y - second.Y));
* }
*/
public Circle()
{
this.Center = new MyPoint(0, 0);
radius = 0;
}
// Calcualte the square of the distance between two MyPoints
public double distance2(MyPoint MyPoint)
{
double dx = x - MyPoint.x;
double dy = y - MyPoint.y;
return (dx * dx + dy * dy);
}
public Circle(MyPoint Center, double radius)
{
this.Center = Center;
this.radius = radius;
}
// Calculate the middle MyPoint between two MyPoints
public MyPoint midMyPoint(MyPoint MyPoint)
{
return new MyPoint((x + MyPoint.x) / 2, (y + MyPoint.y) / 2);
}
// Determine whether two MyPoints are equal
public bool equals(MyPoint MyPoint)
{
return((x == MyPoint.x) && (y == MyPoint.y));
}
