xref: /dragonfly/games/sail/dr_2.c (revision ed183f8c)
1 /*	$NetBSD: dr_2.c,v 1.27 2019/02/03 10:48:46 mrg Exp $	*/
2 
3 /*
4  * Copyright (c) 1983, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #ifndef lint
34 #if 0
35 static char sccsid[] = "@(#)dr_2.c	8.1 (Berkeley) 5/31/93";
36 #else
37 __RCSID("$NetBSD: dr_2.c,v 1.27 2019/02/03 10:48:46 mrg Exp $");
38 #endif
39 #endif /* not lint */
40 
41 #include <stdbool.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #include "extern.h"
46 #include "driver.h"
47 
48 #define couldwin(f,t) (f->specs->crew2 > t->specs->crew2 * 1.5)
49 
50 static int str_end(const char *);
51 static int score(struct ship *, struct ship *, char *, size_t, int);
52 static void move_ship(struct ship *, const char *, unsigned char *,
53 		      short *, short *, int *);
54 static void try(struct ship *f, struct ship *t,
55 		char *command, size_t commandmax, char *temp, size_t tempmax,
56 		int ma, int ta, bool af, int vma, int dir, int *high,
57 		int rakeme);
58 static void rmend(char *);
59 
60 const int dtab[] = {0,1,1,2,3,4,4,5};	/* diagonal distances in x==y */
61 
62 void
63 thinkofgrapples(void)
64 {
65 	struct ship *sp, *sq;
66 	bool friendly;
67 
68 	foreachship(sp) {
69 		if (sp->file->captain[0] || sp->file->dir == 0)
70 			continue;
71 		foreachship(sq) {
72 			friendly = sp->nationality == capship(sq)->nationality;
73 			if (!friendly) {
74 				if (sp->file->struck || sp->file->captured != 0)
75 					continue;
76 				if (range(sp, sq) != 1)
77 					continue;
78 				if (grappled2(sp, sq)) {
79 					if (is_toughmelee(sp, sq, 0, 0))
80 						ungrap(sp, sq);
81 					else
82 						grap(sp, sq);
83 				} else if (couldwin(sp, sq)) {
84 					grap(sp, sq);
85 					sp->file->loadwith = L_GRAPE;
86 				}
87 			} else
88 				ungrap(sp, sq);
89 		}
90 	}
91 }
92 
93 void
94 checkup(void)
95 {
96 	struct ship *sp, *sq;
97 	char explode, sink;
98 
99 	foreachship(sp) {
100 		if (sp->file->dir == 0)
101 			continue;
102 		explode = sp->file->explode;
103 		sink = sp->file->sink;
104 		if (explode != 1 && sink != 1)
105 			continue;
106 		if (dieroll() < 5)
107 			continue;
108 		if (sink == 1) {
109 			send_sink(sp, 2);
110 		} else {
111 			send_explode(sp, 2);
112 		}
113 		send_dir(sp, 0);
114 		if (snagged(sp))
115 			foreachship(sq)
116 				cleansnag(sp, sq, 1);
117 		if (sink != 1) {
118 			makemsg(sp, "exploding!");
119 			foreachship(sq) {
120 				if (sp != sq && sq->file->dir &&
121 				    range(sp, sq) < 4)
122 					table(sp, sq, RIGGING, L_EXPLODE,
123 					      sp->specs->guns/13, 6);
124 			}
125 		} else {
126 			makemsg(sp, "sinking!");
127 		}
128 	}
129 }
130 
131 void
132 prizecheck(void)
133 {
134 	struct ship *sp;
135 
136 	foreachship(sp) {
137 		if (sp->file->captured == 0)
138 			continue;
139 		if (sp->file->struck || sp->file->dir == 0)
140 			continue;
141 		if (sp->specs->crew1 + sp->specs->crew2 + sp->specs->crew3 >
142 		    sp->file->pcrew * 6) {
143 			send_signal(sp, "prize crew overthrown");
144 			send_points(sp->file->captured,
145 			      sp->file->captured->file->points
146 				- 2 * sp->specs->pts);
147 			send_captured(sp, -1);
148 		}
149 	}
150 }
151 
152 static int
153 str_end(const char *str)
154 {
155 	const char *p;
156 
157 	for (p = str; *p; p++)
158 		;
159 	return p == str ? 0 : p[-1];
160 }
161 
162 void
163 closeon(struct ship *from, struct ship *to, char *command, size_t commandmax,
164 	int ta, int ma, bool af)
165 {
166 	int high;
167 	char temp[10];
168 
169 	temp[0] = command[0] = '\0';
170 	high = -30000;
171 	try(from, to, command, commandmax, temp, sizeof(temp),
172 	    ma, ta, af, ma, from->file->dir, &high, 0);
173 }
174 
175 static int
176 score(struct ship *ship, struct ship *to, char *movement, size_t movementmax,
177       int onlytemp)
178 {
179 	int drift;
180 	int row, col, dir, total, ran;
181 	struct File *fp = ship->file;
182 
183 	if ((dir = fp->dir) == 0)
184 		return 0;
185 	row = fp->row;
186 	col = fp->col;
187 	drift = fp->drift;
188 	move_ship(ship, movement, &fp->dir, &fp->row, &fp->col, &drift);
189 	if (!*movement)
190 		strlcpy(movement, "d", movementmax);
191 
192 	ran = range(ship, to);
193 	total = -50 * ran;
194 	if (ran < 4 && gunsbear(ship, to))
195 		total += 60;
196 	if ((ran = portside(ship, to, 1) - fp->dir) == 4 || ran == -4)
197 		total = -30000;
198 
199 	if (!onlytemp) {
200 		fp->row = row;
201 		fp->col = col;
202 		fp->dir = dir;
203 	}
204 	return total;
205 }
206 
207 static void
208 move_ship(struct ship *ship, const char *p, unsigned char *dir,
209 	  short *row, short *col, int *drift)
210 {
211 	int dist;
212 	char moved = 0;
213 
214 	for (; *p; p++) {
215 		switch (*p) {
216 		case 'r':
217 			if (++*dir == 9)
218 				*dir = 1;
219 			break;
220 		case 'l':
221 			if (--*dir == 0)
222 				*dir = 8;
223 			break;
224 		case '1': case '2': case '3': case '4':
225 		case '5': case '6': case '7':
226 			moved++;
227 			if (*dir % 2 == 0)
228 				dist = dtab[*p - '0'];
229 			else
230 				dist = *p - '0';
231 			*row -= dr[*dir] * dist;
232 			*col -= dc[*dir] * dist;
233 			break;
234 		}
235 	}
236 	if (!moved) {
237 		if (windspeed != 0 && ++*drift > 2) {
238 			if ((ship->specs->class >= 3 && !snagged(ship))
239 			    || (turn & 1) == 0) {
240 				*row -= dr[winddir];
241 				*col -= dc[winddir];
242 			}
243 		}
244 	} else
245 		*drift = 0;
246 }
247 
248 static void
249 try(struct ship *f, struct ship *t,
250     char *command, size_t commandmax,
251     char *temp, size_t tempmax,
252     int ma, int ta, bool af, int vma, int dir, int *high, int rakeme)
253 {
254 	int new, n;
255 	char st[11];
256 #define rakeyou (gunsbear(f, t) && !gunsbear(t, f))
257 
258 	if ((n = str_end(temp)) < '1' || n > '9')
259 		for (n = 1; vma - n >= 0; n++) {
260 			snprintf(st, sizeof(st), "%d", n);
261 			strlcat(temp, st, tempmax);
262 			new = score(f, t, temp, tempmax, rakeme);
263 			if (new > *high && (!rakeme || rakeyou)) {
264 				*high = new;
265 				strlcpy(command, temp, commandmax);
266 			}
267 			try(f, t, command, commandmax, temp, tempmax,
268 			    ma-n, ta, af, vma-n,
269 			    dir, high, rakeme);
270 			rmend(temp);
271 		}
272 	if ((ma > 0 && ta > 0 && (n = str_end(temp)) != 'l' && n != 'r') ||
273 	    !strlen(temp)) {
274 		strlcat(temp, "r", tempmax);
275 		new = score(f, t, temp, tempmax, rakeme);
276 		if (new > *high && (!rakeme ||
277 				    (gunsbear(f, t) && !gunsbear(t, f)))) {
278 			*high = new;
279 			strlcpy(command, temp, commandmax);
280 		}
281 		try(f, t, command, commandmax, temp, tempmax,
282 		    ma-1, ta-1, af,
283 		    min(ma-1, maxmove(f, (dir == 8 ? 1 : dir+1), 0)),
284 		    (dir == 8 ? 1 : dir+1), high, rakeme);
285 		rmend(temp);
286 	}
287 	if ((ma > 0 && ta > 0 && (n = str_end(temp)) != 'l' && n != 'r') ||
288 	    !strlen(temp)) {
289 		strlcat(temp, "l", tempmax);
290 		new = score(f, t, temp, tempmax, rakeme);
291 		if (new > *high && (!rakeme ||
292 				    (gunsbear(f, t) && !gunsbear(t, f)))) {
293 			*high = new;
294 			strlcpy(command, temp, commandmax);
295 		}
296 		try(f, t, command, commandmax, temp, tempmax,
297 		    ma-1, ta-1, af,
298 		    (min(ma-1,maxmove(f, (dir-1 ? dir-1 : 8), 0))),
299 		    (dir-1 ? dir -1 : 8), high, rakeme);
300 		rmend(temp);
301 	}
302 }
303 
304 static void
305 rmend(char *str)
306 {
307 	char *p;
308 
309 	for (p = str; *p; p++)
310 		;
311 	if (p != str)
312 		*--p = 0;
313 }
314