include/types/nblist.h

   1 /*
   2  *
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   7  *          GROningen MAchine for Chemical Simulations
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   9  *                        VERSION 3.2.0
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  35 #ifndef _nblist_h
  36 #define _nblist_h
  37
  38 #ifdef __cplusplus
  39 extern "C" {
  40 #endif
  41
  42 /* Neighborlist type */
  43 enum {
  44   enlistATOM_ATOM,
  45   enlistSPC_ATOM,   enlistSPC_SPC,
  46   enlistTIP4P_ATOM, enlistTIP4P_TIP4P,
  47   enlistCG_CG,
  48   enlistNR
  49 };
  50
  51 typedef unsigned long t_excl;
  52
  53 /* The maximum charge group size because of minimum size of t_excl
  54  * could be 32 bits.
  55  */
  56 #define MAX_CHARGEGROUP_SIZE 32
  57
  58 /* The maximum charge group size for CG-CG nblists.
  59  * The excl entry in t_nblist uses blocks of this size.
  60  */
  61 #define MAX_CGCGSIZE 32
  62
  63 typedef struct
  64 {
  65   int             enlist;      /* The type of nblist, enum, see above    */
  66   int             il_code;      /* Innerloop index from nrnb.h, used     */
  67                                 /* for flop accounting.                  */
  68   int             icoul;        /* Coulomb loop type index for kernels   */
  69   int             ivdw;         /* VdW loop type index for kernels       */
  70   int             free_energy;  /* Free energy setting for this list     */
  71
  72   int             nri,maxnri;   /* Current/max number of i particles     */
  73   int             nrj,maxnrj;   /* Current/max number of j particles     */
  74   int             maxlen;       /* maxnr of j atoms for a single i atom  */
  75   int *           iinr;         /* The i-elements                        */
  76   int *           iinr_end;     /* The end atom, only with enlistCG      */
  77   int *           gid;          /* Index in energy arrays                */
  78   int *           shift;        /* Shift vector index                    */
  79   int *           jindex;       /* Index in jjnr                         */
  80   int *           jjnr;         /* The j-atom list                       */
  81   int *           jjnr_end;     /* The end atom, only with enltypeCG     */
  82   t_excl *        excl;         /* Exclusions, only with enltypeCG       */
  83   int             count;        /* counter to multithread the innerloops */
  84   void *          mtx;          /* mutex to lock the counter             */
  85 } t_nblist;
  86
  87
  88 /* For atom I =  nblist->iinr[N] (0 <= N < nblist->nri) there can be
  89  * several neighborlists (N's), for different energy groups (gid) and
  90  * different shifts (shift).
  91  * For corresponding J atoms for each list start at:
  92  * nblist->jjnr[JI]
  93  * with nblist->jindex[N] <= JI < nblist->jindex[N+1]
  94  *
  95  * enlist is of the form enlistUNIT1_UNIT2:
  96  * UNIT ATOM:  there is one atom: iinr[N] or jjnr[JI]
  97  * UNIT SPC:   there are 3 atoms: iinr[N],iinr[N]+1,iinr[N]+2, jjnr analog.
  98  * UNIT TIP4P: there are 4 atoms: iinr[N],...,iinr[N]+3, jjnr analog.
  99  * UNIT CG:    there are N atoms: iinr[N],...,iinr_end[N]-1, jjnr analog.
 100  *
 101  * Clear?
 102  */
 103
 104 #ifdef __cplusplus
 105 }
 106 #endif
 107
 108 #endif