xref: /dragonfly/games/sail/misc.c (revision dcd37f7d)
1 /*-
2  * Copyright (c) 1983, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * @(#)misc.c	8.1 (Berkeley) 5/31/93
30  * $FreeBSD: src/games/sail/misc.c,v 1.5 1999/11/30 03:49:34 billf Exp $
31  * $DragonFly: src/games/sail/misc.c,v 1.4 2006/09/03 17:33:13 pavalos Exp $
32  */
33 
34 #include <sys/file.h>
35 #include "externs.h"
36 #include "pathnames.h"
37 
38 #define distance(x,y) \
39 	(abs(x) >= abs(y) ? abs(x) + abs(y)/2 : abs(y) + abs(x)/2)
40 
41 static int angle(int, int);
42 
43 /* XXX */
44 int
45 range(struct ship *from, struct ship *to)
46 {
47 	int bow1r, bow1c, bow2r, bow2c;
48 	int stern1r, stern1c, stern2c, stern2r;
49 	int bb, bs, sb, ss, result;
50 
51 	if (!to->file->dir)
52 		return -1;
53 	stern1r = bow1r = from->file->row;
54 	stern1c = bow1c = from->file->col;
55 	stern2r = bow2r = to->file->row;
56 	stern2c = bow2c = to->file->col;
57 	result = bb = distance(bow2r - bow1r, bow2c - bow1c);
58 	if (bb < 5) {
59 		stern2r += dr[to->file->dir];
60 		stern2c += dc[to->file->dir];
61 		stern1r += dr[from->file->dir];
62 		stern1c += dc[from->file->dir];
63 		bs = distance((bow2r - stern1r), (bow2c - stern1c));
64 		sb = distance((bow1r - stern2r), (bow1c - stern2c));
65 		ss = distance((stern2r - stern1r) ,(stern2c - stern1c));
66 		result = min(bb, min(bs, min(sb, ss)));
67 	}
68 	return result;
69 }
70 
71 struct ship *
72 closestenemy(struct ship *from, char side, char anyship)
73 {
74 	struct ship *sp;
75 	char a;
76 	int olddist = 30000, dist;
77 	struct ship *closest = 0;
78 
79 	a = capship(from)->nationality;
80 	foreachship(sp) {
81 		if (sp == from)
82 			continue;
83 		if (sp->file->dir == 0)
84 			continue;
85 		if (a == capship(sp)->nationality && !anyship)
86 			continue;
87 		if (side && gunsbear(from, sp) != side)
88 			continue;
89 		dist = range(from, sp);
90 		if (dist < olddist) {
91 			closest = sp;
92 			olddist = dist;
93 		}
94 	}
95 	return closest;
96 }
97 
98 static int
99 angle(int Dr, int Dc)
100 {
101 	int i;
102 
103 	if (Dc >= 0 && Dr > 0)
104 		i = 0;
105 	else if (Dr <= 0 && Dc > 0)
106 		i = 2;
107 	else if (Dc <= 0 && Dr < 0)
108 		i = 4;
109 	else
110 		i = 6;
111 	Dr = abs(Dr);
112 	Dc = abs(Dc);
113 	if ((i == 0 || i == 4) && Dc * 2.4 > Dr) {
114 		i++;
115 		if (Dc > Dr * 2.4)
116 			i++;
117 	} else if ((i == 2 || i == 6) && Dr * 2.4 > Dc) {
118 		i++;
119 		if (Dr > Dc * 2.4)
120 			i++;
121 	}
122 	return i % 8 + 1;
123 }
124 
125 /* checks for target bow or stern */
126 char
127 gunsbear(struct ship *from, struct ship *to)
128 {
129 	int Dr, Dc, i;
130 	int ang;
131 
132 	Dr = from->file->row - to->file->row;
133 	Dc = to->file->col - from->file->col;
134 	for (i = 2; i; i--) {
135 		if ((ang = angle(Dr, Dc) - from->file->dir + 1) < 1)
136 			ang += 8;
137 		if (ang >= 2 && ang <= 4)
138 			return 'r';
139 		if (ang >= 6 && ang <= 7)
140 			return 'l';
141 		Dr += dr[to->file->dir];
142 		Dc += dc[to->file->dir];
143 	}
144 	return 0;
145 }
146 
147 /* returns true if fromship is shooting at onship's starboard side */
148 int
149 portside(struct ship *from, struct ship *on, int quick)
150 {
151 	int ang;
152 	int Dr, Dc;
153 
154 	Dr = from->file->row - on->file->row;
155 	Dc = on->file->col - from->file->col;
156 	if (quick == -1) {
157 		Dr += dr[on->file->dir];
158 		Dc += dc[on->file->dir];
159 	}
160 	ang = angle(Dr, Dc);
161 	if (quick != 0)
162 		return ang;
163 	ang = (ang + 4 - on->file->dir - 1) % 8 + 1;
164 	return ang < 5;
165 }
166 
167 char
168 colours(struct ship *sp)
169 {
170 	char flag = '\0';
171 
172 	if (sp->file->struck)
173 		flag = '!';
174 	if (sp->file->explode)
175 		flag = '#';
176 	if (sp->file->sink)
177 		flag = '~';
178 	if (sp->file->struck)
179 		return flag;
180 	flag = *countryname[capship(sp)->nationality];
181 	return sp->file->FS ? flag : tolower(flag);
182 }
183 
184 void
185 write_log(struct ship *s)
186 {
187 	FILE *fp;
188 	int persons;
189 	int n;
190 	struct logs log[NLOG];
191 	float net;
192 	struct logs *lp;
193 
194 	if ((fp = fopen(_PATH_LOGFILE, "r+")) == NULL)
195 		return;
196 #ifdef LOCK_EX
197 	if (flock(fileno(fp), LOCK_EX) < 0)
198 		return;
199 #endif
200 	net = (float)s->file->points / s->specs->pts;
201 	persons = getw(fp);
202 	n = fread((char *)log, sizeof(struct logs), NLOG, fp);
203 	for (lp = &log[n]; lp < &log[NLOG]; lp++)
204 		lp->l_name[0] = lp->l_uid = lp->l_shipnum
205 			= lp->l_gamenum = lp->l_netpoints = 0;
206 	rewind(fp);
207 	if (persons < 0)
208 		putw(1, fp);
209 	else
210 		putw(persons + 1, fp);
211 	for (lp = log; lp < &log[NLOG]; lp++)
212 		if (net > (float)lp->l_netpoints
213 		    / scene[lp->l_gamenum].ship[lp->l_shipnum].specs->pts) {
214 			fwrite((char *)log,
215 				sizeof (struct logs), lp - log, fp);
216 			strcpy(log[NLOG-1].l_name, s->file->captain);
217 			log[NLOG-1].l_uid = getuid();
218 			log[NLOG-1].l_shipnum = s->file->index;
219 			log[NLOG-1].l_gamenum = game;
220 			log[NLOG-1].l_netpoints = s->file->points;
221 			fwrite((char *)&log[NLOG-1],
222 				sizeof (struct logs), 1, fp);
223 			fwrite((char *)lp,
224 				sizeof (struct logs), &log[NLOG-1] - lp, fp);
225 			break;
226 		}
227 #ifdef LOCK_EX
228 	flock(fileno(fp), LOCK_UN);
229 #endif
230 	fclose(fp);
231 }
232