G4RandomTools.hh File Reference

#include <CLHEP/Units/PhysicalConstants.h>
#include "globals.hh"
#include "Randomize.hh"
#include "G4RandomDirection.hh"

Go to the source code of this file.

Functions
G4ThreeVector	G4LambertianRand (const G4ThreeVector &normal)
G4ThreeVector	G4PlaneVectorRand (const G4ThreeVector &normal)

Function Documentation

G4ThreeVector G4LambertianRand ( const G4ThreeVector &  normal )

inline

Definition at line 55 of file G4RandomTools.hh.

References G4RandomDirection(), and G4UniformRand.

{
  G4ThreeVector vect;
  G4double ndotv;

  do
  {
    vect = G4RandomDirection();
    ndotv = normal * vect;

    if (ndotv < 0.0)
    {
      vect = -vect;
      ndotv = -ndotv;
    }

  } while (!(G4UniformRand() < ndotv));

  return vect;
}

G4ThreeVector G4PlaneVectorRand ( const G4ThreeVector &  normal )

inline

Definition at line 79 of file G4RandomTools.hh.

References CLHEP::Hep3Vector::cross(), G4UniformRand, and CLHEP::Hep3Vector::orthogonal().

{
  G4ThreeVector vec1 = normal.orthogonal();
  G4ThreeVector vec2 = vec1.cross(normal);

  G4double phi = CLHEP::twopi*G4UniformRand();
  G4double cosphi = std::cos(phi);
  G4double sinphi = std::sin(phi);

  return cosphi * vec1 + sinphi * vec2;
}