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// G4VExternalNavigation
//
// Class description:
//
// Pure virtual class to be specialised by the user for tracking with
// an external navigation

// Authors: V.Vlachoudis, G.Cosmo - CERN, 2019
// --------------------------------------------------------------------
#ifndef G4VEXTERNALNAVIGATION_HH
#define G4VEXTERNALNAVIGATION_HH

#include "G4LogicalVolume.hh"
#include "G4NavigationHistory.hh"
#include "G4ThreeVector.hh"
#include "G4VNavigation.hh"
#include "G4VPhysicalVolume.hh"
#include "G4VSolid.hh"

class G4VExternalNavigation : public G4VNavigation
{
  public:  // with description

    G4VExternalNavigation();
      // Constructor
   
    ~G4VExternalNavigation() override;
      // Destructor

    virtual G4VExternalNavigation* Clone() = 0;

    // Optional methods - may be necessary under particular circumstances

    virtual EInside Inside( const G4VSolid*      solid,
                            const G4ThreeVector& position,
                            const G4ThreeVector& direction );
     // Special 'Inside' call that includes direction of next motion
     //   provided for potential optimisations.

    void RelocateWithinVolume( G4VPhysicalVolume*  motherPhysical,
                               const G4ThreeVector& localPoint ) override;
     //   Update any relevant internal state to take account that
     //      - the location has been moved to 'localPoint'
     //      - it remains in the current (mother) physical volume 'motherPhysical'
};

#endif