1 // 2 // Copyright (C) 2013 Paolo Tosco 3 // 4 // Copyright (C) 2004-2006 Rational Discovery LLC 5 // 6 // @@ All Rights Reserved @@ 7 // This file is part of the RDKit. 8 // The contents are covered by the terms of the BSD license 9 // which is included in the file license.txt, found at the root 10 // of the RDKit source tree. 11 // 12 #include <RDGeneral/export.h> 13 #ifndef __RD_MMFFSTRETCHBEND_H__ 14 #define __RD_MMFFSTRETCHBEND_H__ 15 16 #include <utility> 17 #include <ForceField/Contrib.h> 18 19 namespace ForceFields { 20 namespace MMFF { 21 class MMFFBond; 22 class MMFFAngle; 23 class MMFFStbn; 24 class MMFFProp; 25 26 //! The angle-bend term for MMFF 27 class RDKIT_FORCEFIELD_EXPORT StretchBendContrib : public ForceFieldContrib { 28 public: StretchBendContrib()29 StretchBendContrib() {}; 30 //! Constructor 31 /*! 32 The angle is between atom1 - atom2 - atom3 33 34 \param owner pointer to the owning ForceField 35 \param idx1 index of atom1 in the ForceField's positions 36 \param idx2 index of atom2 in the ForceField's positions 37 \param idx3 index of atom3 in the ForceField's positions 38 \param angleType MMFF type of the angle (as an unsigned int) 39 40 */ 41 StretchBendContrib(ForceField *owner, const unsigned int idx1, 42 const unsigned int idx2, const unsigned int idx3, 43 const MMFFStbn *mmffStbnParams, 44 const MMFFAngle *mmffAngleParams, 45 const MMFFBond *mmffBondParams1, 46 const MMFFBond *mmffBondParams2); 47 48 double getEnergy(double *pos) const; 49 void getGrad(double *pos, double *grad) const; copy()50 virtual StretchBendContrib *copy() const { 51 return new StretchBendContrib(*this); 52 }; 53 54 private: 55 int d_at1Idx{-1}, d_at2Idx{-1}, d_at3Idx{-1}; 56 double d_restLen1, d_restLen2, d_theta0; 57 std::pair<double, double> d_forceConstants; 58 }; 59 namespace Utils { 60 //! returns the std::pair of stretch-bend force constants for an angle 61 RDKIT_FORCEFIELD_EXPORT std::pair<double, double> calcStbnForceConstants( 62 const MMFFStbn *mmffStbnParams); 63 //! calculates and returns the stretch-bending MMFF energy 64 RDKIT_FORCEFIELD_EXPORT std::pair<double, double> calcStretchBendEnergy( 65 const double deltaDist1, const double deltaDist2, const double deltaTheta, 66 const std::pair<double, double> forceConstants); 67 } // namespace Utils 68 } // namespace MMFF 69 } // namespace ForceFields 70 #endif 71