GroupRebridgeBase.h

#ifndef MCMD_GROUP_REBRIDGE_BASE_H
#define MCMD_GROUP_REBRIDGE_BASE_H

/*
* Simpatico - Simulation Package for Polymeric and Molecular Liquids
*
* Copyright 2010 - 2017, The Regents of the University of Minnesota
* Distributed under the terms of the GNU General Public License.
*/

#include <mcMd/mcMoves/SystemMove.h>  // base class
#include <mcMd/mcSimulation/McSystem.h>
#ifdef SIMP_ANGLE
#include <mcMd/potentials/angle/AnglePotential.h>
#endif
#include <simp/boundary/Boundary.h>
#include <util/space/Vector.h>

namespace McMd
{

   class Atom;
   class McSystem;

   using namespace Util;
   using namespace Simp;

   class GroupRebridgeBase : public SystemMove 
   {
   
   public:
   
      GroupRebridgeBase(McSystem& system);
   
      virtual ~GroupRebridgeBase();

      void tetraEnergy(Atom* aPtr, Atom* bPtr, Atom* cPtr, Atom* dPtr,
                       int bondType, double &energy);

      #ifdef SIMP_ANGLE

      double angleEnergy(const Atom &a, const Atom &b, const Atom &c, int type);
      #endif

      void octaEnergy(Atom* aPtr, Atom* bPtr, Atom* cPtr, Atom* dPtr,
                      Atom* mPtr, Atom* nPtr, int bondType, double &energy);
  
   };

   #ifdef SIMP_ANGLE
   /*
   */
   inline
   double GroupRebridgeBase::angleEnergy(const Atom &a, const Atom &b,
                       const Atom &c, int type)
   {
      Vector r1, r2;
      double cosTheta;
      system().boundary().distanceSq(b.position(), a.position(), r1);
      system().boundary().distanceSq(c.position(), b.position(), r2);
      r1 /= r1.abs();
      r2 /= r2.abs();
      cosTheta = r1.dot(r2);
      return system().anglePotential().energy(cosTheta, type);
   }
   #endif

}      
#endif