#include "stdio.h"
#include "setup.h"



void getnbhd(i,j,ns,nbvec,typevec,n,m,nsites)  
/************************************************************************* 
  returns the neighbors of the ijth cell of the image.
  nbvec[4] points to the neighboring sites (uses vectorized sites).
  imkey[n][m] holds the "active" pixels 0-active 1-inactive
  xmap[n][m] maps the image sites (i,j) to vector sites k = 0,...,NSITES
***********************************************************************/

int *ns, i, j, *nbvec, *typevec, n, m, nsites;
{
 /* third order neighborhood: */ 
 static int searchkey[12][3] = { 1, 1, 3,  0, 1, 2,  -1, 1, 3,  -1, 0, 1,
                                -1,-1, 3,  0,-1, 2,   1,-1, 3,   1, 0, 1,
                                 2, 0, 4, -2, 0, 4,   0, 2, 4,   0,-2, 4};
 
 /* second order neighborhood 
 static int searchkey[16][3] = { 1, 1, 3,  0, 1, 2,  -1, 1, 3,  -1, 0, 1,
                                -1,-1, 3,  0,-1, 2,   1,-1, 3,   1, 0, 1,
                                 1, 1, 3,  0, 1, 2,  -1, 1, 3,  -1, 0, 1,
                                -1,-1, 3,  0,-1, 2,   1,-1, 3,   1, 0, 1};
 */
 /* First order neighborhoods
 static int searchkey[8][3] = { 0, 1, 2,    -1, 0, 1,
                                0,-1, 2,     1, 0, 1,
                                0, 1, 2,    -1, 0, 1,
                                0,-1, 2,     1, 0, 1};
 */
                                 
 int ii,jj,ival,jval,count, nbmatrix[16][3];

 for(ii=0;ii<12;ii++){
   nbmatrix[ii][0] = i - searchkey[ii][0];
   nbmatrix[ii][1] = j - searchkey[ii][1];
   nbmatrix[ii][2] = searchkey[ii][2];
 }
 *ns = 12;
 count = 12;

   /* remove adjacencies that go off imagekey */

 ii = -1;  
 while(count) {
   ii++;  count--;
   ival = nbmatrix[ii][0];
   jval = nbmatrix[ii][1];
   if(ival < 0 || ival>=n || jval<=-1 || jval>=m) {
       /* remove and adjust remaining */
     for(jj=ii;jj<12;jj++) {
       nbmatrix[jj][0] = nbmatrix[jj+1][0];
       nbmatrix[jj][1] = nbmatrix[jj+1][1];
       nbmatrix[jj][2] = nbmatrix[jj+1][2];
     }
     ii--; *ns -= 1;
   }
 }
 for(ii=0;ii<*ns;ii++){
   nbvec[ii] = nbmatrix[ii][0]*m + nbmatrix[ii][1]%m;
   typevec[ii] = nbmatrix[ii][2];
 }

}