MuonR4::Circle Class Reference

Auxiliary class to construct a circle from three arbitrary points in space. More...

#include <Circle.h>

Collaboration diagram for MuonR4::Circle:

Public Member Functions
	Circle (const Amg::Vector3D &pointA, const Amg::Vector3D &pointB, const Amg::Vector3D &pointC)
	Constructor taking three points in a plane If points are on a line, the plane is set to be the null vector.
const Amg::Vector3D &	center () const
	The center point of the circle.
const Amg::Vector3D &	normal () const
	The vector that is normal to the circle.
double	radius () const
	The radius of the circle.

Private Member Functions
std::ostream &	print (std::ostream &ostr) const

Private Attributes
Amg::Vector3D	m_center {Amg::Vector3D::Zero()}
	The center point of the circle.
Amg::Vector3D	m_normal {Amg::Vector3D::Zero()}
	The plane normal of the circle.
double	m_radius {0.}
	The radius of the circle.

Friends
std::ostream &	operator<< (std::ostream &ostr, const Circle &circ)
	Define the ostream operator.

Detailed Description

Auxiliary class to construct a circle from three arbitrary points in space.

The center point, (signed) radius and the normal vector to the plane spanned by the points are evaluated.

Definition at line 15 of file Circle.h.

Constructor & Destructor Documentation

Circle()

MuonR4::Circle::Circle ( const Amg::Vector3D & pointA, const Amg::Vector3D & pointB, const Amg::Vector3D & pointC )

explicit

Constructor taking three points in a plane If points are on a line, the plane is set to be the null vector.

Parameters

pointA	First circle point
pointB	Second circle point
pointC	Third circle point

Construct the connection line A -> C

Construct the connection line A -> B

The circle plane normal is the normalized cross product between the 2

Calculate the bisector between A + B

Calculate the bisector between A + C

Definition at line 16 of file Circle.cxx.

                                              {
        
        const Amg::Vector3D AC = (pointC - pointA).unit();
        const Amg::Vector3D AB = (pointB - pointA).unit();
        m_normal = AC.cross(AB).unit();
        const Amg::Vector3D midAB = 0.5*(pointA + pointB);
        const Amg::Vector3D midAC = 0.5*(pointA + pointC);
 
        const Amg::Vector3D normAB = AB.cross(m_normal);
        const Amg::Vector3D normAC = AC.cross(m_normal);
 
        const std::optional<double> midIsect = Amg::intersect<3>(midAB, normAB,  midAC, normAC);
        if (!midIsect) {
            m_normal.setZero();
            return;
        }
        m_center = midAC + (*midIsect) * normAC;
        m_radius = std::copysign((pointA - m_center).mag(), (*midIsect));
    }

Member Function Documentation

center()

const Amg::Vector3D & MuonR4::Circle::center ( ) const

inline

The center point of the circle.

Definition at line 28 of file Circle.h.

{ return m_center; }

normal()

const Amg::Vector3D & MuonR4::Circle::normal ( ) const

inline

The vector that is normal to the circle.

Definition at line 30 of file Circle.h.

{ return m_normal; }

print()

std::ostream & MuonR4::Circle::print ( std::ostream & ostr ) const

private

Definition at line 10 of file Circle.cxx.

                                                    {
        ostr<<"Circle - center: "<<Amg::toString(center())
            <<", radius: "<<radius()
            <<", normal: "<<Amg::toString(normal());
        return ostr;
    }

radius()

double MuonR4::Circle::radius ( ) const

inline

The radius of the circle.

Definition at line 32 of file Circle.h.

{ return m_radius; }

Friends And Related Symbol Documentation

operator<<

std::ostream & operator<< ( std::ostream & ostr, const Circle & circ )

friend

Define the ostream operator.

Definition at line 34 of file Circle.h.

                                                                                       {
                return circ.print(ostr);
            }

Member Data Documentation

m_center

Amg::Vector3D MuonR4::Circle::m_center {Amg::Vector3D::Zero()}

private

The center point of the circle.

Definition at line 40 of file Circle.h.

{Amg::Vector3D::Zero()};

m_normal

Amg::Vector3D MuonR4::Circle::m_normal {Amg::Vector3D::Zero()}

private

The plane normal of the circle.

Definition at line 42 of file Circle.h.

{Amg::Vector3D::Zero()};

m_radius

double MuonR4::Circle::m_radius {0.}

private

The radius of the circle.

Definition at line 44 of file Circle.h.

{0.};

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The documentation for this class was generated from the following files:

• Circle.h
• Circle.cxx