Home | History | Annotate | Line # | Download | only in gomoku
      1 /*	$NetBSD: gomoku.h,v 1.56 2022/06/19 10:23:48 rillig 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  *	@(#)gomoku.h	8.2 (Berkeley) 5/3/95
     35  */
     36 
     37 #include <sys/types.h>
     38 #include <sys/endian.h>
     39 #include <stdbool.h>
     40 #include <stdio.h>
     41 
     42 /*
     43  * The gomoku 'board' mainly consists of the playing area of BSZ x BSZ spots.
     44  * The playing area uses 1-based coordinates. Around the playing area is a
     45  * rectangle of border spots, to avoid having to check the coordinates when
     46  * calculating spot coordinates. The left and right border overlap, to save a
     47  * few bytes.
     48  */
     49 
     50 #define BSZ	19
     51 #define BAREA	((1 + BSZ + 1) * (BSZ + 1) + 1)
     52 
     53 /*
     54  * A 'frame' is a group of five or six contiguous spots on the board. An
     55  * open-ended frame is one with spaces on both ends; otherwise, it is closed.
     56  */
     57 #define FAREA	(2 * BSZ * (BSZ - 4) + 2 * (BSZ - 4) * (BSZ - 4))
     58 
     59 
     60 /* The content of a spot on the board; used in s_occ. */
     61 #define BLACK	0
     62 #define WHITE	1
     63 #define EMPTY	2
     64 #define BORDER	3
     65 
     66 /* Either BLACK or WHITE. */
     67 typedef unsigned char player_color;
     68 
     69 /* A spot on the board, or one of the special values below. */
     70 typedef unsigned short spot_index;
     71 #define PT(x, y)	((x) + (BSZ + 1) * (y))
     72 /* return values for makemove, readinput */
     73 #define MOVEOK	0
     74 #define RESIGN	1
     75 #define ILLEGAL	2
     76 #define WIN	3
     77 #define TIE	4
     78 #define SAVE	5
     79 #define END_OF_INPUT 6
     80 
     81 /*
     82  * A 'combo' is a group of intersecting or overlapping frames and consists of
     83  * two numbers:
     84  * 'F' is the number of moves still needed to make the combo non-blockable.
     85  * 'W' is the minimum number of moves needed to win once it can't be blocked.
     86  *
     87  * A 'force' is a combo that is one move away from being non-blockable.
     88  *
     89  * Each time a frame is added to the combo, the number of moves to complete
     90  * the force is the number of moves needed to 'fill' the frame plus one at
     91  * the intersection point. The number of moves to win is the number of moves
     92  * to complete the best frame minus the last move to complete the force.
     93  * Note that it doesn't make sense to combine a <1,x> with anything since
     94  * it is already a force. Also, the frames have to be independent so a
     95  * single move doesn't affect more than one frame making up the combo.
     96  *
     97  * Rules for comparing which of two combos (<F1,W1> <F2,W2>) is better:
     98  * Both the same color:
     99  *	<F',W'> = (F1 < F2 || F1 == F2 && W1 <= W2) ? <F1,W1> : <F2,W2>
    100  *	We want to complete the force first, then the combo with the
    101  *	fewest moves to win.
    102  * Different colors, <F1,W1> is the combo for the player with the next move:
    103  *	<F',W'> = F2 <= 1 && (F1 > 1 || F2 + W2 < F1 + W1) ? <F2,W2> : <F1,W1>
    104  *	We want to block only if we have to (i.e., if they are one move away
    105  *	from completing a force, and we don't have a force that we can
    106  *	complete which takes fewer or the same number of moves to win).
    107  */
    108 
    109 /*
    110  * Single frame combo values:
    111  *     <F,W>	board values
    112  *	5,0	. . . . . O
    113  *	4,1	. . . . . .
    114  *	4,0	. . . . X O
    115  *	3,1	. . . . X .
    116  *	3,0	. . . X X O
    117  *	2,1	. . . X X .
    118  *	2,0	. . X X X O
    119  *	1,1	. . X X X .
    120  *	1,0	. X X X X O
    121  *	0,1	. X X X X .
    122  *	0,0	X X X X X O
    123  *
    124  * The rule for combining two combos (<F1,W1> <F2,W2>) with V valid
    125  * intersection points is:
    126  *	F' = F1 + F2 - 2 - V
    127  *	W' = MIN(F1 + W1 - 1, F2 + W2 - 1)
    128  */
    129 union comboval {
    130 	struct {
    131 #if BYTE_ORDER == BIG_ENDIAN
    132 		u_char	a;
    133 		u_char	b;
    134 #endif
    135 #if BYTE_ORDER == LITTLE_ENDIAN
    136 		u_char	b;
    137 		u_char	a;
    138 #endif
    139 	} c;
    140 	u_short	s;
    141 };
    142 #define cv_force	c.a	/* # moves to complete force */
    143 #define cv_win		c.b	/* # moves to win */
    144 
    145 /*
    146  * This structure is used to record information about single frames (F) and
    147  * combinations of two more frames (C).
    148  * For combinations of two or more frames, there is an additional
    149  * array of pointers to the frames of the combination which is sorted
    150  * by the index into the frames[] array. This is used to prevent duplication
    151  * since frame A combined with B is the same as B with A.
    152  *	struct combostr *c_sort[size c_nframes];
    153  * The leaves of the tree (frames) are numbered 0 (bottom, leftmost)
    154  * to c_nframes - 1 (top, right). This is stored in c_frameindex and
    155  * c_dir if C_LOOP is set.
    156  */
    157 struct combostr {
    158 	struct combostr	*c_next;	/* list of combos at the same level */
    159 	struct combostr	*c_prev;	/* list of combos at the same level */
    160 	struct combostr	*c_link[2];	/* F: NULL,
    161 					 * C: previous level */
    162 	union comboval	c_linkv[2];	/* C: combo value for link[0, 1] */
    163 	union comboval	c_combo;	/* F: initial combo value (read-only),
    164 					 * C: combo value for this level */
    165 	spot_index	c_vertex;	/* F: frame head,
    166 					 * C: intersection */
    167 	u_char		c_nframes;	/* F: 1,
    168 					 * C: number of frames in the combo */
    169 	u_char		c_dir;		/* F: frame direction,
    170 					 * C: loop frame */
    171 	u_char		c_flags;	/* C: combo flags */
    172 	u_char		c_frameindex;	/* C: intersection frame index */
    173 	u_char		c_framecnt[2];	/* number of frames left to attach */
    174 	u_char		c_emask[2];	/* C: bit mask of completion spots for
    175 					 * link[0] and link[1] */
    176 	u_char		c_voff[2];	/* C: vertex offset within frame */
    177 };
    178 
    179 /* flag values for c_flags */
    180 #define C_OPEN_0	0x01		/* link[0] is an open-ended frame */
    181 #define C_OPEN_1	0x02		/* link[1] is an open-ended frame */
    182 #define C_LOOP		0x04		/* link[1] intersects previous frame */
    183 
    184 /*
    185  * This structure is used for recording the completion points of
    186  * multi frame combos.
    187  */
    188 struct	elist {
    189 	struct elist	*e_next;	/* list of completion points */
    190 	struct combostr	*e_combo;	/* the whole combo */
    191 	u_char		e_off;		/* offset in frame of this empty spot */
    192 	u_char		e_frameindex;	/* intersection frame index */
    193 	u_char		e_framecnt;	/* number of frames left to attach */
    194 	u_char		e_emask;	/* real value of the frame's emask */
    195 	union comboval	e_fval;		/* frame combo value */
    196 };
    197 
    198 /* The index of a frame in the global 'frames'. */
    199 typedef unsigned short frame_index;
    200 
    201 /* 0 = right, 1 = down right, 2 = down, 3 = down left. */
    202 typedef unsigned char direction;
    203 #define DIR__R		0		/* right */
    204 #define DIR_DR		1		/* down right */
    205 #define DIR_D_		2		/* down */
    206 #define DIR_DL		3		/* down left */
    207 
    208 /*
    209  * One spot structure for each location on the board.
    210  * A frame consists of the combination for the current spot plus the next
    211  * five spots in the direction.
    212  */
    213 struct	spotstr {
    214 	short		s_occ;		/* color of occupant */
    215 	short		s_wval;		/* weighted value */
    216 	int		s_flags;	/* flags for graph walks */
    217 	frame_index	s_frame[4];	/* level 1 combo for [dir] */
    218 	union comboval	s_fval[2][4];	/* combo value for [color][dir] */
    219 	union comboval	s_combo[2];	/* minimum combo value for [color] */
    220 	u_char		s_level[2];	/* number of frames in the min combo */
    221 	u_char		s_nforce[2];	/* number of <1,x> combos */
    222 	struct elist	*s_empty;	/* level n combo completion spots */
    223 	struct elist	*s_nempty;	/* level n+1 combo completion spots */
    224 };
    225 
    226 /* flag values for s_flags */
    227 #define CFLAG		0x000001	/* frame is part of a combo */
    228 #define CFLAGALL	0x00000F	/* all frame directions marked */
    229 #define IFLAG		0x000010	/* legal intersection point */
    230 #define IFLAGALL	0x0000F0	/* any intersection points? */
    231 #define FFLAG		0x000100	/* frame is part of a <1,x> combo */
    232 #define FFLAGALL	0x000F00	/* all force frames */
    233 #define MFLAG		0x001000	/* frame has already been seen */
    234 #define MFLAGALL	0x00F000	/* all frames seen */
    235 #define BFLAG		0x010000	/* frame intersects border or dead */
    236 #define BFLAGALL	0x0F0000	/* all frames dead */
    237 
    238 static inline bool
    239 is_blocked(const struct spotstr *sp, direction r)
    240 {
    241 	return (sp->s_flags & (BFLAG << r)) != 0;
    242 }
    243 
    244 static inline void
    245 set_blocked(struct spotstr *sp, direction r)
    246 {
    247 	sp->s_flags |= BFLAG << r;
    248 }
    249 
    250 struct game {
    251 	unsigned int	nmoves;		/* number of played moves */
    252 	spot_index	moves[BSZ * BSZ]; /* log of all played moves */
    253 	spot_index	win_spot;	/* the winning move, or 0 */
    254 	direction	win_dir;
    255 	int		user_x;
    256 	int		user_y;
    257 };
    258 
    259 extern	const char	letters[];
    260 extern	const char	pdir[];
    261 
    262 extern	const int     dd[4];
    263 extern	struct	spotstr	board[BAREA];		/* info for board */
    264 extern	struct	combostr frames[FAREA];		/* storage for single frames */
    265 extern	struct	combostr *sortframes[2];	/* sorted, non-empty frames */
    266 extern	u_char	overlap[FAREA * FAREA];
    267 extern	spot_index intersect[FAREA * FAREA];	/* frame [a][b] intersection */
    268 extern	struct game	game;
    269 extern	int	debug;
    270 
    271 extern bool interactive;
    272 extern const char *plyr[];
    273 
    274 void	init_board(void);
    275 spot_index get_coord(void);
    276 int	get_key(const char *);
    277 bool	get_line(char *, int, void (*)(const char *));
    278 void	ask(const char *);
    279 void	dislog(const char *);
    280 void	bdump(FILE *);
    281 void	bdisp(void);
    282 void	bdisp_init(void);
    283 void	cursfini(void);
    284 void	cursinit(void);
    285 void	bdwho(void);
    286 void	panic(const char *, ...) __printflike(1, 2) __dead;
    287 void	debuglog(const char *, ...) __printflike(1, 2);
    288 void	whatsup(int);
    289 const char *stoc(spot_index);
    290 spot_index ctos(const char *);
    291 int	makemove(player_color, spot_index);
    292 void	clearcombo(struct combostr *, int);
    293 void	markcombo(struct combostr *);
    294 spot_index pickmove(player_color);
    295 #if defined(DEBUG)
    296 void	printcombo(struct combostr *, char *, size_t);
    297 #endif
    298