G4BoundingSphereScene.cc

Go to the documentation of this file.

//
// ********************************************************************
// * License and Disclaimer                                           *
// *                                                                  *
// * The  Geant4 software  is  copyright of the Copyright Holders  of *
// * the Geant4 Collaboration.  It is provided  under  the terms  and *
// * conditions of the Geant4 Software License,  included in the file *
// * LICENSE and available at  http://cern.ch/geant4/license .  These *
// * include a list of copyright holders.                             *
// *                                                                  *
// * Neither the authors of this software system, nor their employing *
// * institutes,nor the agencies providing financial support for this *
// * work  make  any representation or  warranty, express or implied, *
// * regarding  this  software system or assume any liability for its *
// * use.  Please see the license in the file  LICENSE  and URL above *
// * for the full disclaimer and the limitation of liability.         *
// *                                                                  *
// * This  code  implementation is the result of  the  scientific and *
// * technical work of the GEANT4 collaboration.                      *
// * By using,  copying,  modifying or  distributing the software (or *
// * any work based  on the software)  you  agree  to acknowledge its *
// * use  in  resulting  scientific  publications,  and indicate your *
// * acceptance of all terms of the Geant4 Software license.          *
// ********************************************************************
//
//
//
// 
// John Allison  7th June 1997
// An artificial scene to reuse G4VScene code to calculate a bounding sphere.
 
#include "G4BoundingSphereScene.hh"
 
#include "G4VSolid.hh"
#include "G4PhysicalVolumeModel.hh"
#include "G4Vector3D.hh"
 
G4BoundingSphereScene::G4BoundingSphereScene (G4VModel* pModel)
:fpModel(pModel)
,fRadius(-1.)
{}
 
G4BoundingSphereScene::~G4BoundingSphereScene () {}
 
G4VisExtent G4BoundingSphereScene::GetBoundingSphereExtent () {
  return G4VisExtent (fCentre, fRadius);
}
 
void G4BoundingSphereScene::ProcessVolume(const G4VSolid& solid)
{
  const G4VisExtent& newExtent = solid.GetExtent ();
  G4Point3D newCentre = newExtent.GetExtentCentre ();
  if (fpCurrentObjectTransformation) {
    newCentre.transform (*fpCurrentObjectTransformation);
  }
  const G4double newRadius = newExtent.GetExtentRadius ();
  AccrueBoundingSphere (newCentre, newRadius);
 
  // Curtail descent - can assume daughters are contained within mother...
  G4PhysicalVolumeModel* pPVM = dynamic_cast<G4PhysicalVolumeModel*>(fpModel);
  if (pPVM) pPVM->CurtailDescent();
}
 
void G4BoundingSphereScene::ResetBoundingSphere () {
  fCentre = G4Point3D ();
  fRadius = -1.;
  fpCurrentObjectTransformation = 0;
}
 
void G4BoundingSphereScene::AccrueBoundingSphere
(const G4Point3D& newCentre,
 G4double newRadius) {
 
  if (fRadius < 0 ) {  // First time.
    fCentre = newCentre;
    fRadius = newRadius;
  }
  else {
    G4Vector3D join = newCentre - fCentre;
    if (join == G4Vector3D (0., 0., 0.)) {             // Centres coincide.
      if (fRadius < newRadius) fRadius = newRadius;
    }
    else if (join.mag () + newRadius <= fRadius) {  // Inside accrued sphere.
      // Do nothing.
    }
    else {
      G4Vector3D unitJoin = join.unit ();
      G4Point3D oldExtremity1 = fCentre - fRadius * unitJoin;
      G4Point3D newExtremity1 = newCentre - newRadius * unitJoin;
      G4Point3D oldExtremity2 = fCentre + fRadius * unitJoin;
      G4Point3D newExtremity2 = newCentre + newRadius * unitJoin;
      G4Point3D extremity1;
      if (oldExtremity1 * unitJoin < newExtremity1 * unitJoin) {
    extremity1 = oldExtremity1;
      }
      else {
    extremity1 = newExtremity1;
      }
      G4Point3D extremity2;
      if (oldExtremity2 * unitJoin > newExtremity2 * unitJoin) {
    extremity2 = oldExtremity2;
      }
      else {
    extremity2 = newExtremity2;
      }
      fCentre = 0.5 * (extremity2 + extremity1);
      fRadius = 0.5 * (extremity2 - extremity1).mag ();
    }
  }
}