JMARKOV::JPhotonPath Class Reference

A photon path. More...

#include <JPhotonPath.hh>

Inheritance diagram for JMARKOV::JPhotonPath:

Public Member Functions
	JPhotonPath ()
	default constructor
	JPhotonPath (int _nscat)
	constructor to actually be used
string	getString ()
	get a string with the path vertex positions
double	getLength ()
	get the total path length
void	addVertex ()
void	addVertex (JPosition3D &pos)
bool	hitsSphere (const JPosition3D &pos, double r)
	Returns whether the photon path intersects a sphere of radius r at position pos.
JPosition3D	getSphereHitPosition (const JPosition3D &pos, double r)
	Returns the position where the photon hits a sphere of radius r at position pos. If the photon does not hit, it returns (0,0,0).
std::vector< JPosition3D >	getPointsWithX (double x)
	return all coordinates where the photon path has the given x
std::vector< JPosition3D >	getPointsWithY (double y)
	return all coordinates where the photon path has the given y
std::vector< JPosition3D >	getPointsWithZ (double z)
	return all coordinates where the photon path has the given z
JIO::JReader &	read (JIO::JReader &in)
	Read from input.
JIO::JWriter &	write (JIO::JWriter &out) const
	Write to output.
const JPolyline3D &	getPolyline () const
	Get polyline.
JPolyline3D &	getPolyline ()
	Get polyline.
JPolyline3D &	transform (const JMatrix3D &T)
	Transform all vertices.
void	transform (const JRotation3D &R, const JVector3D &pos)
	Transform all vertices of the polyline with a rotation and offset.
JPolyline3D &	rotate (const JRotation3D &R)
	Rotate all vertices.
JPolyline3D &	rotate (const JRotation3X &R)
	Rotate all vertices around X-axis.
JPolyline3D &	rotate (const JRotation3Y &R)
	Rotate all vertices around Y-axis.
JPolyline3D &	rotate (const JRotation3Z &R)
	Rotate all vertices around Z-axis.
JPolyline3D &	rotate_back (const JRotation3D &R)
	Rotate back all vertices.
JPolyline3D &	rotate_back (const JRotation3X &R)
	Rotate all vertices back around X-axis.
JPolyline3D &	rotate_back (const JRotation3Y &R)
	Rotate all vertices back around Y-axis.
JPolyline3D &	rotate_back (const JRotation3Z &R)
	Rotate all vertices back around Z-axis.
void	transform_back (const JRotation3D &R, const JVector3D &pos)
	Transform back all vertices of the polyline.

Public Attributes
int	n
double	weight

Detailed Description

A photon path.

This is basically a JPolyline3D with at least two vertices and a weight.

Definition at line 38 of file JPhotonPath.hh.

Constructor & Destructor Documentation

JPhotonPath() [1/2]

JMARKOV::JPhotonPath::JPhotonPath ( )

inline

default constructor

Definition at line 42 of file JPhotonPath.hh.

: n(2), weight(1) { resize(n) ; }

JPhotonPath() [2/2]

JMARKOV::JPhotonPath::JPhotonPath ( int _nscat )

inline

constructor to actually be used

Definition at line 45 of file JPhotonPath.hh.

: n(_nscat+2), weight(1) { resize(n) ; }

Member Function Documentation

getString()

string JMARKOV::JPhotonPath::getString

(

)

get a string with the path vertex positions

Definition at line 136 of file JPhotonPath.hh.

                                {
    ostringstream oss ;
    for( unsigned int i=0 ; i<size() ; ++i ) {
      oss << at(i) ;
      if( i+1!=size() ) oss << ", " ;
    }
    return oss.str() ;
  }

getLength()

double JMARKOV::JPhotonPath::getLength

(

)

get the total path length

Definition at line 104 of file JPhotonPath.hh.

                                {
    iterator v1 = begin() ;
    iterator v2(v1) ;
    ++v2 ;
    double L = 0 ;
    for(  ; v2!=end() ; ++v1,++v2 ) {
      // length of path segment
      L += (*v2-*v1).getLength() ;
    }
    return L ;
  }

addVertex() [1/2]

void JMARKOV::JPhotonPath::addVertex ( )

inline

Definition at line 53 of file JPhotonPath.hh.

                     {
      JPosition3D pos(0,0,0) ;
      addVertex(pos) ;
    }

addVertex() [2/2]

void JMARKOV::JPhotonPath::addVertex

(

JPosition3D &

pos

)

Definition at line 116 of file JPhotonPath.hh.

                                                {
    ++n ;
    push_back(pos) ;
  }

hitsSphere()

bool JMARKOV::JPhotonPath::hitsSphere	(	const JPosition3D &	pos,
		double	r )

Returns whether the photon path intersects a sphere of radius r at position pos.

Definition at line 176 of file JPhotonPath.hh.

                                                                 {
    // loop over the path segments
    for( unsigned int i=1 ; i<size() ; ++i ) {
      // the current path segment is from x1 to x2
 
      // vector pointing from x1 to x2
      JPosition3D seg = at(i)-at(i-1) ;
      JVersor3D dir_seg(seg) ; // normalized version of seg
      double Lseg = seg.getLength() ;
 
      // vector pointing from the center of the sphere to x1
      JPosition3D to_center(at(i-1)-pos) ;
      JVersor3D dir_to_center(to_center) ; // normalized version of to_center
      double r_to_center = to_center.getLength() ;
 
      // cosine of angle between the two directions
      double ct = dir_seg.getDot(dir_to_center) ;
      
      // if sin^2(theta) > (r_to_center/radius)^2
      if( 1-ct*ct > r*r/(r_to_center*r_to_center) ) {
        // definitely no hit in this segment
        // continue with the next one
        continue ;
      }
 
      // the segment can be parametrized as x1 + xi * dir_seg
      // where xi is in the range [0,Lseg]
      // there are two possible solutions for xi
      double D = sqrt( r_to_center*r_to_center*(ct*ct-1) + r*r ) ;
      double xi1 = -r_to_center*ct + D ;
      if( xi1>0 && xi1<Lseg ) return true ;
      double xi2 = -r_to_center*ct - D ;
      if( xi2>0 && xi2<Lseg ) return true ;
    }
    return false ;
  }

getSphereHitPosition()

JPosition3D JMARKOV::JPhotonPath::getSphereHitPosition	(	const JPosition3D &	pos,
		double	r )

Returns the position where the photon hits a sphere of radius r at position pos. If the photon does not hit, it returns (0,0,0).

Definition at line 213 of file JPhotonPath.hh.

                                                                                  {
    // loop over the path segments
    for( unsigned int i=1 ; i<size() ; ++i ) {
      // the current path segment is from x1 to x2
 
      // vector pointing from x1 to x2
      JPosition3D seg = at(i)-at(i-1) ;
      JVersor3D dir_seg(seg) ; // normalized version of seg
      double Lseg = seg.getLength() ;
 
      // vector pointing from the center of the sphere to x1
      JPosition3D to_center(at(i-1)-pos) ;
      JVersor3D dir_to_center(to_center) ; // normalized version of to_center
      double r_to_center = to_center.getLength() ;
 
      // cosine of angle between the two directions
      double ct = dir_seg.getDot(dir_to_center) ;
      
      // if sin^2(theta) > (r_to_center/radius)^2
      if( 1-ct*ct > r*r/(r_to_center*r_to_center) ) {
        // definitely no hit in this segment
        // continue with the next one
        continue ;
      }
 
      // the segment can be parametrized as x1 + xi * dir_seg
      // where xi is in the range [0,Lseg]
      // there are two possible solutions for xi
      double D = sqrt( r_to_center*r_to_center*(ct*ct-1) + r*r ) ;
 
      // first xi
      double xi1 = -r_to_center*ct + D ;
      if( xi1<0 || xi1>Lseg ) {
        xi1 = 1.1*Lseg ;
      }
 
      // second xi
      double xi2 = -r_to_center*ct - D ;
      // if this is a xi within the segment
      if( xi2>0 && xi2<Lseg ) {
        // and it is before xi1, we replace xi1
        if( xi2<xi1 ) xi1 = xi2 ;
      }
 
      if( xi1>0 && xi1<Lseg ) {
        return at(i-1) + JPosition3D(dir_seg)*xi1 ;
      }
    }
    return JPosition3D(0,0,0) ;
  }

getPointsWithX()

std::vector< JPosition3D > JMARKOV::JPhotonPath::getPointsWithX

(

double

x

)

return all coordinates where the photon path has the given x

Definition at line 121 of file JPhotonPath.hh.

                                                               {
    std::vector<JPosition3D> res ;
 
    // loop over the path segments
    for( unsigned int i=1 ; i<size() ; ++i ) {
      JPosition3D v1( at(i-1) ) ;
      JPosition3D v2( at(i)   ) ;
      if( (v1.getX()>x) != (v2.getX()>x) ) {
        double frac =  (x-v1.getX())/(v2.getX()-v1.getX()) ;
        res.push_back( v1+frac*(v2-v1) ) ;
      }
    }
    return res ;
  }

getPointsWithY()

std::vector< JPosition3D > JMARKOV::JPhotonPath::getPointsWithY

(

double

y

)

return all coordinates where the photon path has the given y

Definition at line 145 of file JPhotonPath.hh.

                                                               {
    std::vector<JPosition3D> res ;
 
    // loop over the path segments
    for( unsigned int i=1 ; i<size() ; ++i ) {
      JPosition3D v1( at(i-1) ) ;
      JPosition3D v2( at(i)   ) ;
      if( (v1.getY()>y) != (v2.getY()>y) ) {
        double frac =  (y-v1.getY())/(v2.getY()-v1.getY()) ;
        res.push_back( v1+frac*(v2-v1) ) ;
      }
    }
    return res ;
  }

getPointsWithZ()

std::vector< JPosition3D > JMARKOV::JPhotonPath::getPointsWithZ

(

double

z

)

return all coordinates where the photon path has the given z

Definition at line 160 of file JPhotonPath.hh.

                                                               {
    std::vector<JPosition3D> res ;
 
    // loop over the path segments
    for( unsigned int i=1 ; i<size() ; ++i ) {
      JPosition3D v1( at(i-1) ) ;
      JPosition3D v2( at(i)   ) ;
      if( (v1.getZ()>z) != (v2.getZ()>z) ) {
        double frac =  (z-v1.getZ())/(v2.getZ()-v1.getZ()) ;
        res.push_back( v1+frac*(v2-v1) ) ;
      }
    }
    return res ;
  }

read()

JIO::JReader & JMARKOV::JPhotonPath::read ( JIO::JReader & in )

inlinevirtual

Read from input.

Parameters

in

JReader

Returns

JReader

Implements JIO::JSerialisable.

Definition at line 75 of file JPhotonPath.hh.

                                      {
      // read number of vertices and adjust size accordingly
      in >> n ;
      if( n>0 ) resize(n) ;
      // read vertices
      for( iterator it=begin() ; it!=end() ; ++it )
        in >> *it ;
      // read weight
      in >> weight ;
 
      return in ;
    }

write()

JIO::JWriter & JMARKOV::JPhotonPath::write ( JIO::JWriter & out ) const

inlinevirtual

Write to output.

Parameters

out

JWriter

Returns

JWriter

Implements JIO::JSerialisable.

Definition at line 88 of file JPhotonPath.hh.

                                              {
      // write size
      out << (int)size() ;
      // write vertices
      for( const_iterator it=begin() ; it!=end() ; ++it )
        out << *it ; //it->getX() << it->getY() << it->getZ() ;
      // write weight
      out << weight ;
 
      return out ;
    }

getPolyline() [1/2]

const JPolyline3D & JGEOMETRY3D::JPolyline3D::getPolyline ( ) const

inlineinherited

Get polyline.

Returns

polyline

Definition at line 43 of file JPolyline3D.hh.

                                           {
      return static_cast<const JPolyline3D&>(*this);
    }

getPolyline() [2/2]

JPolyline3D & JGEOMETRY3D::JPolyline3D::getPolyline ( )

inlineinherited

Get polyline.

Returns

polyline

Definition at line 52 of file JPolyline3D.hh.

    {
      return static_cast<JPolyline3D&>(*this);
    }

transform() [1/2]

JPolyline3D & JGEOMETRY3D::JPolyline3D::transform ( const JMatrix3D & T )

inlineinherited

Transform all vertices.

Parameters

T

matrix

Definition at line 62 of file JPolyline3D.hh.

                                               {
      for( iterator it=begin(); it!=end() ; ++it ) it->transform(T) ;
      return *this;
    }

transform() [2/2]

void JGEOMETRY3D::JPolyline3D::transform ( const JRotation3D & R, const JVector3D & pos )

inlineinherited

Transform all vertices of the polyline with a rotation and offset.

See the corresponding function in JPosition3D for more information

Parameters

R	rotation matrix
pos	position of origin (after rotation)

Definition at line 157 of file JPolyline3D.hh.

                                                               {      
      for( iterator it=begin(); it!=end() ; ++it ) it->transform(R,pos) ;
    }

rotate() [1/4]

JPolyline3D & JGEOMETRY3D::JPolyline3D::rotate ( const JRotation3D & R )

inlineinherited

Rotate all vertices.

Parameters

R	rotation matrix

Definition at line 72 of file JPolyline3D.hh.

    {
      for( iterator it=begin(); it!=end() ; ++it ) it->rotate(R);
      return *this;
    }

rotate() [2/4]

JPolyline3D & JGEOMETRY3D::JPolyline3D::rotate ( const JRotation3X & R )

inlineinherited

Rotate all vertices around X-axis.

Parameters

R	rotation matrix

Definition at line 93 of file JPolyline3D.hh.

                                              {
      for( iterator it=begin(); it!=end() ; ++it ) it->rotate(R);
      return *this;
    }

rotate() [3/4]

JPolyline3D & JGEOMETRY3D::JPolyline3D::rotate ( const JRotation3Y & R )

inlineinherited

Rotate all vertices around Y-axis.

Parameters

R	rotation matrix

Definition at line 114 of file JPolyline3D.hh.

                                              {
      for( iterator it=begin(); it!=end() ; ++it ) it->rotate(R);
      return *this;
    }

rotate() [4/4]

JPolyline3D & JGEOMETRY3D::JPolyline3D::rotate ( const JRotation3Z & R )

inlineinherited

Rotate all vertices around Z-axis.

Parameters

R	rotation matrix

Definition at line 135 of file JPolyline3D.hh.

                                             {
      for( iterator it=begin(); it!=end() ; ++it ) it->rotate(R);
      return *this;
    }

rotate_back() [1/4]

JPolyline3D & JGEOMETRY3D::JPolyline3D::rotate_back ( const JRotation3D & R )

inlineinherited

Rotate back all vertices.

Parameters

R	rotation matrix

Definition at line 83 of file JPolyline3D.hh.

                                                   {
      for( iterator it=begin(); it!=end() ; ++it ) it->rotate_back(R) ;
      return *this;
    }

rotate_back() [2/4]

JPolyline3D & JGEOMETRY3D::JPolyline3D::rotate_back ( const JRotation3X & R )

inlineinherited

Rotate all vertices back around X-axis.

Parameters

R	rotation matrix

Definition at line 103 of file JPolyline3D.hh.

                                                   {      
      for( iterator it=begin(); it!=end() ; ++it ) it->rotate_back(R) ;
      return *this;
    }

rotate_back() [3/4]

JPolyline3D & JGEOMETRY3D::JPolyline3D::rotate_back ( const JRotation3Y & R )

inlineinherited

Rotate all vertices back around Y-axis.

Parameters

R	rotation matrix

Definition at line 125 of file JPolyline3D.hh.

                                                   {      
      for( iterator it=begin(); it!=end() ; ++it ) it->rotate_back(R) ;
      return *this;
    }

rotate_back() [4/4]

JPolyline3D & JGEOMETRY3D::JPolyline3D::rotate_back ( const JRotation3Z & R )

inlineinherited

Rotate all vertices back around Z-axis.

Parameters

R	rotation matrix

Definition at line 145 of file JPolyline3D.hh.

                                                   {      
      for( iterator it=begin(); it!=end() ; ++it ) it->rotate_back(R) ;
      return *this;
    }

transform_back()

void JGEOMETRY3D::JPolyline3D::transform_back ( const JRotation3D & R, const JVector3D & pos )

inlineinherited

Transform back all vertices of the polyline.

Parameters

R	rotation matrix
pos	polyline of origin (before rotation)

Definition at line 167 of file JPolyline3D.hh.

                                                                      {
      for( iterator it=begin(); it!=end() ; ++it ) it->transform_back(R,pos) ;
    }

Member Data Documentation

n

int JMARKOV::JPhotonPath::n

Definition at line 100 of file JPhotonPath.hh.

weight

double JMARKOV::JPhotonPath::weight

Definition at line 101 of file JPhotonPath.hh.

---

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

• JPhotonPath.hh