/// <summary>
/// Computes the centre of the circumcircle of this vertex and two others.
/// </summary>
/// <param name="b" />
/// <param name="c" />
/// <returns>the Coordinate which is the circumcircle of the 3 points.</returns>
public Vertex CircleCenter(Vertex b, Vertex c)
{
var a = new Vertex(X, Y);
// compute the perpendicular bisector of cord ab
var cab = Bisector(a, b);
// compute the perpendicular bisector of cord bc
var cbc = Bisector(b, c);
// compute the intersection of the bisectors (circle radii)
var hcc = new HCoordinate(cab, cbc);
Vertex cc = null;
try
{
cc = new Vertex(hcc.GetX(), hcc.GetY());
}
catch (NotRepresentableException nre)
{
#if !PCL
Debug.WriteLine("a: " + a + " b: " + b + " c: " + c);
Debug.WriteLine(nre);
#endif
//throw;
}
return(cc);
}
///<summary>Computes the circumcentre of a triangle.</summary>
/// <remarks>
/// The circumcentre is the centre of the circumcircle,
/// the smallest circle which encloses the triangle.
/// It is also the common intersection point of the
/// perpendicular bisectors of the sides of the triangle,
/// and is the only point which has equal distance to all three
/// vertices of the triangle.
/// </remarks>
/// <param name="a">A vertex of the triangle</param>
/// <param name="b">A vertex of the triangle</param>
/// <param name="c">A vertex of the triangle</param>
/// <returns>The circumcentre of the triangle</returns>
public static Coordinate Circumcentre(Coordinate a, Coordinate b, Coordinate c)
{
// compute the perpendicular bisector of chord ab
HCoordinate cab = PerpendicularBisector(a, b);
// compute the perpendicular bisector of chord bc
HCoordinate cbc = PerpendicularBisector(b, c);
// compute the intersection of the bisectors (circle radii)
HCoordinate hcc = new HCoordinate(cab, cbc);
Coordinate cc;
try
{
cc = new Coordinate(hcc.GetX(), hcc.GetY());
}
catch (NotRepresentableException ex)
{
// MD - not sure what we can do to prevent this (robustness problem)
// Idea - can we condition which edges we choose?
throw new InvalidOperationException(ex.Message);
}
return(cc);
}
/// <summary>
/// Computes the centre of the circumcircle of this vertex and two others.
/// </summary>
/// <param name="b" />
/// <param name="c" />
/// <returns>the Coordinate which is the circumcircle of the 3 points.</returns>
public Vertex CircleCenter(Vertex b, Vertex c)
{
Vertex a = new Vertex(this.X, this.Y);
// compute the perpendicular bisector of cord ab
HCoordinate cab = Bisector(a, b);
// compute the perpendicular bisector of cord bc
HCoordinate cbc = Bisector(b, c);
// compute the intersection of the bisectors (circle radii)
HCoordinate hcc = new HCoordinate(cab, cbc);
Vertex cc = null;
try
{
cc = new Vertex(hcc.GetX(), hcc.GetY());
}
catch (NotRepresentableException nre)
{
System.Console.WriteLine("a: " + a + " b: " + b + " c: " + c);
System.Console.WriteLine(nre);
}
return(cc);
}