xref: /dragonfly/games/gomoku/bdinit.c (revision 00b5bfed)
1 /*	$NetBSD: bdinit.c,v 1.9 2012/10/13 20:57:35 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  *	@(#)bdinit.c	8.2 (Berkeley) 5/3/95
35  */
36 
37 #include <string.h>
38 #include "gomoku.h"
39 
40 static void init_overlap(void);
41 
42 void
bdinit(struct spotstr * bp)43 bdinit(struct spotstr *bp)
44 {
45 	int i, j, r;
46 	struct spotstr *sp;
47 	struct combostr *cbp;
48 
49 	movenum = 1;
50 
51 	/* mark the borders as such */
52 	sp = bp;
53 	for (i = BSZ2; --i >= 0; sp++) {
54 		sp->s_occ = BORDER;		/* top border */
55 		sp->s_flags = BFLAGALL;
56 	}
57 
58 	/* fill entire board with EMPTY spots */
59 	memset(frames, 0, sizeof(frames));
60 	cbp = frames;
61 	for (j = 0; ++j < BSZ1; sp++) {			/* for each row */
62 		for (i = 0; ++i < BSZ1; sp++) {		/* for each column */
63 			sp->s_occ = EMPTY;
64 			sp->s_flags = 0;
65 			sp->s_wval = 0;
66 			if (j < 5) {
67 				/* directions 1, 2, 3 are blocked */
68 				sp->s_flags |= (BFLAG << 1) | (BFLAG << 2) |
69 					(BFLAG << 3);
70 				sp->s_fval[BLACK][1].s = MAXCOMBO;
71 				sp->s_fval[BLACK][2].s = MAXCOMBO;
72 				sp->s_fval[BLACK][3].s = MAXCOMBO;
73 				sp->s_fval[WHITE][1].s = MAXCOMBO;
74 				sp->s_fval[WHITE][2].s = MAXCOMBO;
75 				sp->s_fval[WHITE][3].s = MAXCOMBO;
76 			} else if (j == 5) {
77 				/* five spaces, blocked on one side */
78 				sp->s_fval[BLACK][1].s = 0x500;
79 				sp->s_fval[BLACK][2].s = 0x500;
80 				sp->s_fval[BLACK][3].s = 0x500;
81 				sp->s_fval[WHITE][1].s = 0x500;
82 				sp->s_fval[WHITE][2].s = 0x500;
83 				sp->s_fval[WHITE][3].s = 0x500;
84 			} else {
85 				/* six spaces, not blocked */
86 				sp->s_fval[BLACK][1].s = 0x401;
87 				sp->s_fval[BLACK][2].s = 0x401;
88 				sp->s_fval[BLACK][3].s = 0x401;
89 				sp->s_fval[WHITE][1].s = 0x401;
90 				sp->s_fval[WHITE][2].s = 0x401;
91 				sp->s_fval[WHITE][3].s = 0x401;
92 			}
93 			if (i > (BSZ - 4)) {
94 				/* directions 0, 1 are blocked */
95 				sp->s_flags |= BFLAG | (BFLAG << 1);
96 				sp->s_fval[BLACK][0].s = MAXCOMBO;
97 				sp->s_fval[BLACK][1].s = MAXCOMBO;
98 				sp->s_fval[WHITE][0].s = MAXCOMBO;
99 				sp->s_fval[WHITE][1].s = MAXCOMBO;
100 			} else if (i == (BSZ - 4)) {
101 				sp->s_fval[BLACK][0].s = 0x500;
102 				sp->s_fval[WHITE][0].s = 0x500;
103 				/* if direction 1 is not blocked */
104 				if (!(sp->s_flags & (BFLAG << 1))) {
105 					sp->s_fval[BLACK][1].s = 0x500;
106 					sp->s_fval[WHITE][1].s = 0x500;
107 				}
108 			} else {
109 				sp->s_fval[BLACK][0].s = 0x401;
110 				sp->s_fval[WHITE][0].s = 0x401;
111 				if (i < 5) {
112 					/* direction 3 is blocked */
113 					sp->s_flags |= (BFLAG << 3);
114 					sp->s_fval[BLACK][3].s = MAXCOMBO;
115 					sp->s_fval[WHITE][3].s = MAXCOMBO;
116 				} else if (i == 5 &&
117 				    !(sp->s_flags & (BFLAG << 3))) {
118 					sp->s_fval[BLACK][3].s = 0x500;
119 					sp->s_fval[WHITE][3].s = 0x500;
120 				}
121 			}
122 			/*
123 			 * Allocate a frame structure for non blocked frames.
124 			 */
125 			for (r = 4; --r >= 0; ) {
126 				if (sp->s_flags & (BFLAG << r))
127 					continue;
128 				cbp->c_combo.s = sp->s_fval[BLACK][r].s;
129 				cbp->c_vertex = sp - board;
130 				cbp->c_nframes = 1;
131 				cbp->c_dir = r;
132 				sp->s_frame[r] = cbp;
133 				cbp++;
134 			}
135 		}
136 		sp->s_occ = BORDER;		/* left & right border */
137 		sp->s_flags = BFLAGALL;
138 	}
139 
140 	/* mark the borders as such */
141 	for (i = BSZ1; --i >= 0; sp++) {
142 		sp->s_occ = BORDER;		/* bottom border */
143 		sp->s_flags = BFLAGALL;
144 	}
145 
146 	sortframes[BLACK] = (struct combostr *)0;
147 	sortframes[WHITE] = (struct combostr *)0;
148 	init_overlap();
149 }
150 
151 /*
152  * Initialize the overlap array.
153  * Each entry in the array is a bit mask with eight bits corresponding
154  * to whether frame B overlaps frame A (as indexed by overlap[A * FAREA + B]).
155  * The eight bits coorespond to whether A and B are open ended (length 6) or
156  * closed (length 5).
157  *	0	A closed and B closed
158  *	1	A closed and B open
159  *	2	A open and B closed
160  *	3	A open and B open
161  *	4	A closed and B closed and overlaps in more than one spot
162  *	5	A closed and B open and overlaps in more than one spot
163  *	6	A open and B closed and overlaps in more than one spot
164  *	7	A open and B open and overlaps in more than one spot
165  * As pieces are played, it can make frames not overlap if there are no
166  * common open spaces shared between the two frames.
167  */
168 static void
init_overlap(void)169 init_overlap(void)
170 {
171 	struct spotstr *sp1, *sp2;
172 	struct combostr *cbp;
173 	unsigned frameix;
174 	int i, f, r, n, d1, d2;
175 	int mask, bmask, vertex, s;
176 	u_char *str;
177 	short *ip;
178 
179 	memset(overlap, 0, sizeof(overlap));
180 	memset(intersect, 0, sizeof(intersect));
181 	str = &overlap[FAREA * FAREA];
182 	ip = &intersect[FAREA * FAREA];
183 	for (frameix = FAREA; frameix-- > 0; ) {	/* each frame */
184 	    cbp = &frames[frameix];
185 	    str -= FAREA;
186 	    ip -= FAREA;
187 	    sp1 = &board[vertex = cbp->c_vertex];
188 	    d1 = dd[r = cbp->c_dir];
189 	    /*
190 	     * s = 5 if closed, 6 if open.
191 	     * At this point black & white are the same.
192 	     */
193 	    s = 5 + sp1->s_fval[BLACK][r].c.b;
194 	    /* for each spot in frame A */
195 	    for (i = 0; i < s; i++, sp1 += d1, vertex += d1) {
196 		/* the sixth spot in frame A only overlaps if it is open */
197 		mask = (i == 5) ? 0xC : 0xF;
198 		/* for each direction */
199 		for (r = 4; --r >= 0; ) {
200 		    bmask = BFLAG << r;
201 		    sp2 = sp1;
202 		    d2 = dd[r];
203 		    /* for each frame that intersects at spot sp1 */
204 		    for (f = 0; f < 6; f++, sp2 -= d2) {
205 			if (sp2->s_occ == BORDER)
206 			    break;
207 			if (sp2->s_flags & bmask)
208 			    continue;
209 			n = sp2->s_frame[r] - frames;
210 			ip[n] = vertex;
211 			str[n] |= (f == 5) ? mask & 0xA : mask;
212 			if (r == cbp->c_dir) {
213 			    /* compute the multiple spot overlap values */
214 			    switch (i) {
215 			    case 0:	/* sp1 is the first spot in A */
216 				if (f == 4)
217 				    str[n] |= 0xA0;
218 				else if (f != 5)
219 				    str[n] |= 0xF0;
220 				break;
221 			    case 1:	/* sp1 is the second spot in A */
222 				if (f == 5)
223 				    str[n] |= 0xA0;
224 				else
225 				    str[n] |= 0xF0;
226 				break;
227 			    case 4:	/* sp1 is the penultimate spot in A */
228 				if (f == 0)
229 				    str[n] |= 0xC0;
230 				else
231 				    str[n] |= 0xF0;
232 				break;
233 			    case 5:	/* sp1 is the last spot in A */
234 				if (f == 1)
235 				    str[n] |= 0xC0;
236 				else if (f != 0)
237 				    str[n] |= 0xF0;
238 				break;
239 			    default:
240 				str[n] |= 0xF0;
241 			    }
242 			}
243 		    }
244 		}
245 	    }
246 	}
247 }
248