games/gomoku/bdinit.c

   1 /*      $NetBSD: bdinit.c,v 1.7 2009/06/04 05:43:29 dholland Exp $      */
   2
   3 /*
   4  * Copyright (c) 1994
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * This code is derived from software contributed to Berkeley by
   8  * Ralph Campbell.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #include <sys/cdefs.h>
  36 #ifndef lint
  37 #if 0
  38 static char sccsid[] = "from: @(#)bdinit.c      8.2 (Berkeley) 5/3/95";
  39 #else
  40 __RCSID("$NetBSD: bdinit.c,v 1.7 2009/06/04 05:43:29 dholland Exp $");
  41 #endif
  42 #endif /* not lint */
  43
  44 #include <string.h>
  45 #include "gomoku.h"
  46
  47 static void init_overlap(void);
  48
  49 void
  50 bdinit(struct spotstr *bp)
  51 {
  52         int i, j, r;
  53         struct spotstr *sp;
  54         struct combostr *cbp;
  55
  56         movenum = 1;
  57
  58         /* mark the borders as such */
  59         sp = bp;
  60         for (i = BSZ2; --i >= 0; sp++) {
  61                 sp->s_occ = BORDER;             /* top border */
  62                 sp->s_flags = BFLAGALL;
  63         }
  64
  65         /* fill entire board with EMPTY spots */
  66         memset(frames, 0, sizeof(frames));
  67         cbp = frames;
  68         for (j = 0; ++j < BSZ1; sp++) {                 /* for each row */
  69                 for (i = 0; ++i < BSZ1; sp++) {         /* for each column */
  70                         sp->s_occ = EMPTY;
  71                         sp->s_flags = 0;
  72                         sp->s_wval = 0;
  73                         if (j < 5) {
  74                                 /* directions 1, 2, 3 are blocked */
  75                                 sp->s_flags |= (BFLAG << 1) | (BFLAG << 2) |
  76                                         (BFLAG << 3);
  77                                 sp->s_fval[BLACK][1].s = MAXCOMBO;
  78                                 sp->s_fval[BLACK][2].s = MAXCOMBO;
  79                                 sp->s_fval[BLACK][3].s = MAXCOMBO;
  80                                 sp->s_fval[WHITE][1].s = MAXCOMBO;
  81                                 sp->s_fval[WHITE][2].s = MAXCOMBO;
  82                                 sp->s_fval[WHITE][3].s = MAXCOMBO;
  83                         } else if (j == 5) {
  84                                 /* five spaces, blocked on one side */
  85                                 sp->s_fval[BLACK][1].s = 0x500;
  86                                 sp->s_fval[BLACK][2].s = 0x500;
  87                                 sp->s_fval[BLACK][3].s = 0x500;
  88                                 sp->s_fval[WHITE][1].s = 0x500;
  89                                 sp->s_fval[WHITE][2].s = 0x500;
  90                                 sp->s_fval[WHITE][3].s = 0x500;
  91                         } else {
  92                                 /* six spaces, not blocked */
  93                                 sp->s_fval[BLACK][1].s = 0x401;
  94                                 sp->s_fval[BLACK][2].s = 0x401;
  95                                 sp->s_fval[BLACK][3].s = 0x401;
  96                                 sp->s_fval[WHITE][1].s = 0x401;
  97                                 sp->s_fval[WHITE][2].s = 0x401;
  98                                 sp->s_fval[WHITE][3].s = 0x401;
  99                         }
 100                         if (i > (BSZ - 4)) {
 101                                 /* directions 0, 1 are blocked */
 102                                 sp->s_flags |= BFLAG | (BFLAG << 1);
 103                                 sp->s_fval[BLACK][0].s = MAXCOMBO;
 104                                 sp->s_fval[BLACK][1].s = MAXCOMBO;
 105                                 sp->s_fval[WHITE][0].s = MAXCOMBO;
 106                                 sp->s_fval[WHITE][1].s = MAXCOMBO;
 107                         } else if (i == (BSZ - 4)) {
 108                                 sp->s_fval[BLACK][0].s = 0x500;
 109                                 sp->s_fval[WHITE][0].s = 0x500;
 110                                 /* if direction 1 is not blocked */
 111                                 if (!(sp->s_flags & (BFLAG << 1))) {
 112                                         sp->s_fval[BLACK][1].s = 0x500;
 113                                         sp->s_fval[WHITE][1].s = 0x500;
 114                                 }
 115                         } else {
 116                                 sp->s_fval[BLACK][0].s = 0x401;
 117                                 sp->s_fval[WHITE][0].s = 0x401;
 118                                 if (i < 5) {
 119                                         /* direction 3 is blocked */
 120                                         sp->s_flags |= (BFLAG << 3);
 121                                         sp->s_fval[BLACK][3].s = MAXCOMBO;
 122                                         sp->s_fval[WHITE][3].s = MAXCOMBO;
 123                                 } else if (i == 5 &&
 124                                     !(sp->s_flags & (BFLAG << 3))) {
 125                                         sp->s_fval[BLACK][3].s = 0x500;
 126                                         sp->s_fval[WHITE][3].s = 0x500;
 127                                 }
 128                         }
 129                         /*
 130                          * Allocate a frame structure for non blocked frames.
 131                          */
 132                         for (r = 4; --r >= 0; ) {
 133                                 if (sp->s_flags & (BFLAG << r))
 134                                         continue;
 135                                 cbp->c_combo.s = sp->s_fval[BLACK][r].s;
 136                                 cbp->c_vertex = sp - board;
 137                                 cbp->c_nframes = 1;
 138                                 cbp->c_dir = r;
 139                                 sp->s_frame[r] = cbp;
 140                                 cbp++;
 141                         }
 142                 }
 143                 sp->s_occ = BORDER;             /* left & right border */
 144                 sp->s_flags = BFLAGALL;
 145         }
 146
 147         /* mark the borders as such */
 148         for (i = BSZ1; --i >= 0; sp++) {
 149                 sp->s_occ = BORDER;             /* bottom border */
 150                 sp->s_flags = BFLAGALL;
 151         }
 152
 153         sortframes[BLACK] = (struct combostr *)0;
 154         sortframes[WHITE] = (struct combostr *)0;
 155         init_overlap();
 156 }
 157
 158 /*
 159  * Initialize the overlap array.
 160  * Each entry in the array is a bit mask with eight bits corresponding
 161  * to whether frame B overlaps frame A (as indexed by overlap[A * FAREA + B]).
 162  * The eight bits coorespond to whether A and B are open ended (length 6) or
 163  * closed (length 5).
 164  *      0       A closed and B closed
 165  *      1       A closed and B open
 166  *      2       A open and B closed
 167  *      3       A open and B open
 168  *      4       A closed and B closed and overlaps in more than one spot
 169  *      5       A closed and B open and overlaps in more than one spot
 170  *      6       A open and B closed and overlaps in more than one spot
 171  *      7       A open and B open and overlaps in more than one spot
 172  * As pieces are played, it can make frames not overlap if there are no
 173  * common open spaces shared between the two frames.
 174  */
 175 static void
 176 init_overlap(void)
 177 {
 178         struct spotstr *sp1, *sp2;
 179         struct combostr *cbp;
 180         int i, f, r, n, d1, d2;
 181         int mask, bmask, vertex, s;
 182         u_char *str;
 183         short *ip;
 184
 185         memset(overlap, 0, sizeof(overlap));
 186         memset(intersect, 0, sizeof(intersect));
 187         str = &overlap[FAREA * FAREA];
 188         ip = &intersect[FAREA * FAREA];
 189         for (cbp = frames + FAREA; --cbp >= frames; ) {         /* each frame */
 190             str -= FAREA;
 191             ip -= FAREA;
 192             sp1 = &board[vertex = cbp->c_vertex];
 193             d1 = dd[r = cbp->c_dir];
 194             /*
 195              * s = 5 if closed, 6 if open.
 196              * At this point black & white are the same.
 197              */
 198             s = 5 + sp1->s_fval[BLACK][r].c.b;
 199             /* for each spot in frame A */
 200             for (i = 0; i < s; i++, sp1 += d1, vertex += d1) {
 201                 /* the sixth spot in frame A only overlaps if it is open */
 202                 mask = (i == 5) ? 0xC : 0xF;
 203                 /* for each direction */
 204                 for (r = 4; --r >= 0; ) {
 205                     bmask = BFLAG << r;
 206                     sp2 = sp1;
 207                     d2 = dd[r];
 208                     /* for each frame that intersects at spot sp1 */
 209                     for (f = 0; f < 6; f++, sp2 -= d2) {
 210                         if (sp2->s_occ == BORDER)
 211                             break;
 212                         if (sp2->s_flags & bmask)
 213                             continue;
 214                         n = sp2->s_frame[r] - frames;
 215                         ip[n] = vertex;
 216                         str[n] |= (f == 5) ? mask & 0xA : mask;
 217                         if (r == cbp->c_dir) {
 218                             /* compute the multiple spot overlap values */
 219                             switch (i) {
 220                             case 0:     /* sp1 is the first spot in A */
 221                                 if (f == 4)
 222                                     str[n] |= 0xA0;
 223                                 else if (f != 5)
 224                                     str[n] |= 0xF0;
 225                                 break;
 226                             case 1:     /* sp1 is the second spot in A */
 227                                 if (f == 5)
 228                                     str[n] |= 0xA0;
 229                                 else
 230                                     str[n] |= 0xF0;
 231                                 break;
 232                             case 4:     /* sp1 is the penultimate spot in A */
 233                                 if (f == 0)
 234                                     str[n] |= 0xC0;
 235                                 else
 236                                     str[n] |= 0xF0;
 237                                 break;
 238                             case 5:     /* sp1 is the last spot in A */
 239                                 if (f == 1)
 240                                     str[n] |= 0xC0;
 241                                 else if (f != 0)
 242                                     str[n] |= 0xF0;
 243                                 break;
 244                             default:
 245                                 str[n] |= 0xF0;
 246                             }
 247                         }
 248                     }
 249                 }
 250             }
 251         }
 252 }