xref: /netbsd-src/games/gomoku/bdinit.c (revision 8e6ab8837d8d6b9198e67c1c445300b483e2f304)
1 /*	$NetBSD: bdinit.c,v 1.5 2003/08/07 09:37:15 agc 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 1.5 2003/08/07 09:37:15 agc Exp $");
41 #endif
42 #endif /* not lint */
43 
44 #include <string.h>
45 #include "gomoku.h"
46 
47 void
48 bdinit(bp)
49 	struct spotstr *bp;
50 {
51 	int i, j, r;
52 	struct spotstr *sp;
53 	struct combostr *cbp;
54 
55 	movenum = 1;
56 
57 	/* mark the borders as such */
58 	sp = bp;
59 	for (i = BSZ2; --i >= 0; sp++) {
60 		sp->s_occ = BORDER;		/* top border */
61 		sp->s_flg = BFLAGALL;
62 	}
63 
64 	/* fill entire board with EMPTY spots */
65 	memset(frames, 0, sizeof(frames));
66 	cbp = frames;
67 	for (j = 0; ++j < BSZ1; sp++) {			/* for each row */
68 		for (i = 0; ++i < BSZ1; sp++) {		/* for each column */
69 			sp->s_occ = EMPTY;
70 			sp->s_flg = 0;
71 			sp->s_wval = 0;
72 			if (j < 5) {
73 				/* directions 1, 2, 3 are blocked */
74 				sp->s_flg |= (BFLAG << 1) | (BFLAG << 2) |
75 					(BFLAG << 3);
76 				sp->s_fval[BLACK][1].s = MAXCOMBO;
77 				sp->s_fval[BLACK][2].s = MAXCOMBO;
78 				sp->s_fval[BLACK][3].s = MAXCOMBO;
79 				sp->s_fval[WHITE][1].s = MAXCOMBO;
80 				sp->s_fval[WHITE][2].s = MAXCOMBO;
81 				sp->s_fval[WHITE][3].s = MAXCOMBO;
82 			} else if (j == 5) {
83 				/* five spaces, blocked on one side */
84 				sp->s_fval[BLACK][1].s = 0x500;
85 				sp->s_fval[BLACK][2].s = 0x500;
86 				sp->s_fval[BLACK][3].s = 0x500;
87 				sp->s_fval[WHITE][1].s = 0x500;
88 				sp->s_fval[WHITE][2].s = 0x500;
89 				sp->s_fval[WHITE][3].s = 0x500;
90 			} else {
91 				/* six spaces, not blocked */
92 				sp->s_fval[BLACK][1].s = 0x401;
93 				sp->s_fval[BLACK][2].s = 0x401;
94 				sp->s_fval[BLACK][3].s = 0x401;
95 				sp->s_fval[WHITE][1].s = 0x401;
96 				sp->s_fval[WHITE][2].s = 0x401;
97 				sp->s_fval[WHITE][3].s = 0x401;
98 			}
99 			if (i > (BSZ - 4)) {
100 				/* directions 0, 1 are blocked */
101 				sp->s_flg |= BFLAG | (BFLAG << 1);
102 				sp->s_fval[BLACK][0].s = MAXCOMBO;
103 				sp->s_fval[BLACK][1].s = MAXCOMBO;
104 				sp->s_fval[WHITE][0].s = MAXCOMBO;
105 				sp->s_fval[WHITE][1].s = MAXCOMBO;
106 			} else if (i == (BSZ - 4)) {
107 				sp->s_fval[BLACK][0].s = 0x500;
108 				sp->s_fval[WHITE][0].s = 0x500;
109 				/* if direction 1 is not blocked */
110 				if (!(sp->s_flg & (BFLAG << 1))) {
111 					sp->s_fval[BLACK][1].s = 0x500;
112 					sp->s_fval[WHITE][1].s = 0x500;
113 				}
114 			} else {
115 				sp->s_fval[BLACK][0].s = 0x401;
116 				sp->s_fval[WHITE][0].s = 0x401;
117 				if (i < 5) {
118 					/* direction 3 is blocked */
119 					sp->s_flg |= (BFLAG << 3);
120 					sp->s_fval[BLACK][3].s = MAXCOMBO;
121 					sp->s_fval[WHITE][3].s = MAXCOMBO;
122 				} else if (i == 5 &&
123 				    !(sp->s_flg & (BFLAG << 3))) {
124 					sp->s_fval[BLACK][3].s = 0x500;
125 					sp->s_fval[WHITE][3].s = 0x500;
126 				}
127 			}
128 			/*
129 			 * Allocate a frame structure for non blocked frames.
130 			 */
131 			for (r = 4; --r >= 0; ) {
132 				if (sp->s_flg & (BFLAG << r))
133 					continue;
134 				cbp->c_combo.s = sp->s_fval[BLACK][r].s;
135 				cbp->c_vertex = sp - board;
136 				cbp->c_nframes = 1;
137 				cbp->c_dir = r;
138 				sp->s_frame[r] = cbp;
139 				cbp++;
140 			}
141 		}
142 		sp->s_occ = BORDER;		/* left & right border */
143 		sp->s_flg = BFLAGALL;
144 	}
145 
146 	/* mark the borders as such */
147 	for (i = BSZ1; --i >= 0; sp++) {
148 		sp->s_occ = BORDER;		/* bottom border */
149 		sp->s_flg = BFLAGALL;
150 	}
151 
152 	sortframes[BLACK] = (struct combostr *)0;
153 	sortframes[WHITE] = (struct combostr *)0;
154 	init_overlap();
155 }
156 
157 /*
158  * Initialize the overlap array.
159  * Each entry in the array is a bit mask with eight bits corresponding
160  * to whether frame B overlaps frame A (as indexed by overlap[A * FAREA + B]).
161  * The eight bits coorespond to whether A and B are open ended (length 6) or
162  * closed (length 5).
163  *	0	A closed and B closed
164  *	1	A closed and B open
165  *	2	A open and B closed
166  *	3	A open and B open
167  *	4	A closed and B closed and overlaps in more than one spot
168  *	5	A closed and B open and overlaps in more than one spot
169  *	6	A open and B closed and overlaps in more than one spot
170  *	7	A open and B open and overlaps in more than one spot
171  * As pieces are played, it can make frames not overlap if there are no
172  * common open spaces shared between the two frames.
173  */
174 void
175 init_overlap()
176 {
177 	struct spotstr *sp1, *sp2;
178 	struct combostr *cbp;
179 	int i, f, r, n, d1, d2;
180 	int mask, bmask, vertex, s;
181 	u_char *str;
182 	short *ip;
183 
184 	memset(overlap, 0, sizeof(overlap));
185 	memset(intersect, 0, sizeof(intersect));
186 	str = &overlap[FAREA * FAREA];
187 	ip = &intersect[FAREA * FAREA];
188 	for (cbp = frames + FAREA; --cbp >= frames; ) {		/* each frame */
189 	    str -= FAREA;
190 	    ip -= FAREA;
191 	    sp1 = &board[vertex = cbp->c_vertex];
192 	    d1 = dd[r = cbp->c_dir];
193 	    /*
194 	     * s = 5 if closed, 6 if open.
195 	     * At this point black & white are the same.
196 	     */
197 	    s = 5 + sp1->s_fval[BLACK][r].c.b;
198 	    /* for each spot in frame A */
199 	    for (i = 0; i < s; i++, sp1 += d1, vertex += d1) {
200 		/* the sixth spot in frame A only overlaps if it is open */
201 		mask = (i == 5) ? 0xC : 0xF;
202 		/* for each direction */
203 		for (r = 4; --r >= 0; ) {
204 		    bmask = BFLAG << r;
205 		    sp2 = sp1;
206 		    d2 = dd[r];
207 		    /* for each frame that intersects at spot sp1 */
208 		    for (f = 0; f < 6; f++, sp2 -= d2) {
209 			if (sp2->s_occ == BORDER)
210 			    break;
211 			if (sp2->s_flg & bmask)
212 			    continue;
213 			n = sp2->s_frame[r] - frames;
214 			ip[n] = vertex;
215 			str[n] |= (f == 5) ? mask & 0xA : mask;
216 			if (r == cbp->c_dir) {
217 			    /* compute the multiple spot overlap values */
218 			    switch (i) {
219 			    case 0:	/* sp1 is the first spot in A */
220 				if (f == 4)
221 				    str[n] |= 0xA0;
222 				else if (f != 5)
223 				    str[n] |= 0xF0;
224 				break;
225 			    case 1:	/* sp1 is the second spot in A */
226 				if (f == 5)
227 				    str[n] |= 0xA0;
228 				else
229 				    str[n] |= 0xF0;
230 				break;
231 			    case 4:	/* sp1 is the penultimate spot in A */
232 				if (f == 0)
233 				    str[n] |= 0xC0;
234 				else
235 				    str[n] |= 0xF0;
236 				break;
237 			    case 5:	/* sp1 is the last spot in A */
238 				if (f == 1)
239 				    str[n] |= 0xC0;
240 				else if (f != 0)
241 				    str[n] |= 0xF0;
242 				break;
243 			    default:
244 				str[n] |= 0xF0;
245 			    }
246 			}
247 		    }
248 		}
249 	    }
250 	}
251 }
252