/*************************************************************************/
/*                                                                       */
/*  Copyright (c) 1994 Stanford University                               */
/*                                                                       */
/*  All rights reserved.                                                 */
/*                                                                       */
/*  Permission is given to use, copy, and modify this software for any   */
/*  non-commercial purpose as long as this copyright notice is not       */
/*  removed.  All other uses, including redistribution in whole or in    */
/*  part, are forbidden without prior written permission.                */
/*                                                                       */
/*  This software is provided with absolutely no warranty and no         */
/*  support.                                                             */
/*                                                                       */
/*************************************************************************/

EXTERN_ENV

#include <stdio.h>
#include <math.h>

#include "decs.h"


void subblock()
{
    long i;
    long j;
    long k;
    long xportion;
    long yportion;
    long my_num;

/* Determine starting coord and number of points to process in     */
/* each direction                                                  */

    for (i = 0; i < numlev; i++) {
        xportion = (jmx[i] - 2) / xprocs;
        //xextra = (jmx[i] - 2) % xprocs;
        for (j = 0; j < xprocs; j++) {
            for (k = 0; k < yprocs; k++) {
                gp[k * xprocs + j].rel_num_x[i] = xportion;
            }
        }
        yportion = (imx[i] - 2) / yprocs;
        //yextra = (imx[i] - 2) % yprocs;
        for (j = 0; j < yprocs; j++) {
            for (k = 0; k < xprocs; k++) {
                gp[j * xprocs + k].rel_num_y[i] = yportion;
            }
        }
    }

    for (my_num = 0; my_num < nprocs; my_num++) {
        for (i = 0; i < numlev; i++) {
            gp[my_num].rlist[i] = 1;
            gp[my_num].rljst[i] = 1;
            gp[my_num].rlien[i] = gp[my_num].rlist[i] + gp[my_num].rel_num_y[i];
            gp[my_num].rljen[i] = gp[my_num].rljst[i] + gp[my_num].rel_num_x[i];
            gp[my_num].eist[i] = gp[my_num].rlist[i] + 1;
            gp[my_num].oist[i] = gp[my_num].rlist[i];
            gp[my_num].ejst[i] = gp[my_num].rljst[i] + 1;
            gp[my_num].ojst[i] = gp[my_num].rljst[i];
        }
    }
    
    for (i = 0; i < nprocs; i++) {
        gp[i].neighbors[LEFT] = -1;
        gp[i].neighbors[RIGHT] = -1;
        gp[i].neighbors[UP] = -1;
        gp[i].neighbors[DOWN] = -1;
        gp[i].neighbors[UPLEFT] = -1;
        gp[i].neighbors[UPRIGHT] = -1;
        gp[i].neighbors[DOWNLEFT] = -1;
        gp[i].neighbors[DOWNRIGHT] = -1;
        
        if (i >= xprocs) {
            gp[i].neighbors[UP] = i - xprocs;
        }
        if (i < nprocs - xprocs) {
            gp[i].neighbors[DOWN] = i + xprocs;
        }
        if ((i % xprocs) > 0) {
            gp[i].neighbors[LEFT] = i - 1;
        }
        if ((i % xprocs) < (xprocs - 1)) {
            gp[i].neighbors[RIGHT] = i + 1;
        }
        
        j = gp[i].neighbors[UP];
        
        if (j != -1) {
            if ((j % xprocs) > 0) {
                gp[i].neighbors[UPLEFT] = j - 1;
            }
            if ((j % xprocs) < (xprocs - 1)) {
                gp[i].neighbors[UPRIGHT] = j + 1;
            }
        }
        
        j = gp[i].neighbors[DOWN];
        
        if (j != -1) {
            if ((j % xprocs) > 0) {
                gp[i].neighbors[DOWNLEFT] = j - 1;
            }
            if ((j % xprocs) < (xprocs - 1)) {
                gp[i].neighbors[DOWNRIGHT] = j + 1;
            }
        }
    }
    
    for (i = 0; i < nprocs; i++) {
        (*gp[i].rownum) = i / xprocs;
        (*gp[i].colnum) = i % xprocs;
    }
}