xref: /dragonfly/games/sail/misc.c (revision 0ca59c34)
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  */
32 
33 #include <sys/file.h>
34 #include "externs.h"
35 #include "pathnames.h"
36 
37 #define distance(x,y) \
38 	(abs(x) >= abs(y) ? abs(x) + abs(y)/2 : abs(y) + abs(x)/2)
39 
40 static int angle(int, int);
41 
42 /* XXX */
43 int
44 range(struct ship *from, struct ship *to)
45 {
46 	int bow1r, bow1c, bow2r, bow2c;
47 	int stern1r, stern1c, stern2c, stern2r;
48 	int bb, bs, sb, ss, result;
49 
50 	if (!to->file->dir)
51 		return -1;
52 	stern1r = bow1r = from->file->row;
53 	stern1c = bow1c = from->file->col;
54 	stern2r = bow2r = to->file->row;
55 	stern2c = bow2c = to->file->col;
56 	result = bb = distance(bow2r - bow1r, bow2c - bow1c);
57 	if (bb < 5) {
58 		stern2r += dr[to->file->dir];
59 		stern2c += dc[to->file->dir];
60 		stern1r += dr[from->file->dir];
61 		stern1c += dc[from->file->dir];
62 		bs = distance((bow2r - stern1r), (bow2c - stern1c));
63 		sb = distance((bow1r - stern2r), (bow1c - stern2c));
64 		ss = distance((stern2r - stern1r) ,(stern2c - stern1c));
65 		result = min(bb, min(bs, min(sb, ss)));
66 	}
67 	return result;
68 }
69 
70 struct ship *
71 closestenemy(struct ship *from, char side, char anyship)
72 {
73 	struct ship *sp;
74 	char a;
75 	int olddist = 30000, dist;
76 	struct ship *closest = NULL;
77 
78 	a = capship(from)->nationality;
79 	foreachship(sp) {
80 		if (sp == from)
81 			continue;
82 		if (sp->file->dir == 0)
83 			continue;
84 		if (a == capship(sp)->nationality && !anyship)
85 			continue;
86 		if (side && gunsbear(from, sp) != side)
87 			continue;
88 		dist = range(from, sp);
89 		if (dist < olddist) {
90 			closest = sp;
91 			olddist = dist;
92 		}
93 	}
94 	return closest;
95 }
96 
97 static int
98 angle(int Dr, int Dc)
99 {
100 	int i;
101 
102 	if (Dc >= 0 && Dr > 0)
103 		i = 0;
104 	else if (Dr <= 0 && Dc > 0)
105 		i = 2;
106 	else if (Dc <= 0 && Dr < 0)
107 		i = 4;
108 	else
109 		i = 6;
110 	Dr = abs(Dr);
111 	Dc = abs(Dc);
112 	if ((i == 0 || i == 4) && Dc * 2.4 > Dr) {
113 		i++;
114 		if (Dc > Dr * 2.4)
115 			i++;
116 	} else if ((i == 2 || i == 6) && Dr * 2.4 > Dc) {
117 		i++;
118 		if (Dr > Dc * 2.4)
119 			i++;
120 	}
121 	return i % 8 + 1;
122 }
123 
124 /* checks for target bow or stern */
125 char
126 gunsbear(struct ship *from, struct ship *to)
127 {
128 	int Dr, Dc, i;
129 	int ang;
130 
131 	Dr = from->file->row - to->file->row;
132 	Dc = to->file->col - from->file->col;
133 	for (i = 2; i; i--) {
134 		if ((ang = angle(Dr, Dc) - from->file->dir + 1) < 1)
135 			ang += 8;
136 		if (ang >= 2 && ang <= 4)
137 			return 'r';
138 		if (ang >= 6 && ang <= 7)
139 			return 'l';
140 		Dr += dr[to->file->dir];
141 		Dc += dc[to->file->dir];
142 	}
143 	return 0;
144 }
145 
146 /* returns true if fromship is shooting at onship's starboard side */
147 int
148 portside(struct ship *from, struct ship *on, int quick)
149 {
150 	int ang;
151 	int Dr, Dc;
152 
153 	Dr = from->file->row - on->file->row;
154 	Dc = on->file->col - from->file->col;
155 	if (quick == -1) {
156 		Dr += dr[on->file->dir];
157 		Dc += dc[on->file->dir];
158 	}
159 	ang = angle(Dr, Dc);
160 	if (quick != 0)
161 		return ang;
162 	ang = (ang + 4 - on->file->dir - 1) % 8 + 1;
163 	return ang < 5;
164 }
165 
166 char
167 colours(struct ship *sp)
168 {
169 	char flag = '\0';
170 
171 	if (sp->file->struck)
172 		flag = '!';
173 	if (sp->file->explode)
174 		flag = '#';
175 	if (sp->file->sink)
176 		flag = '~';
177 	if (sp->file->struck)
178 		return flag;
179 	flag = *countryname[capship(sp)->nationality];
180 	return sp->file->FS ? flag : tolower(flag);
181 }
182 
183 void
184 write_log(struct ship *s)
185 {
186 	FILE *fp;
187 	int persons;
188 	int n;
189 	struct logs log[NLOG];
190 	float net;
191 	struct logs *lp;
192 
193 	if ((fp = fopen(_PATH_LOGFILE, "r+")) == NULL)
194 		return;
195 #ifdef LOCK_EX
196 	if (flock(fileno(fp), LOCK_EX) < 0)
197 		return;
198 #endif
199 	net = (float)s->file->points / s->specs->pts;
200 	persons = getw(fp);
201 	n = fread((char *)log, sizeof(struct logs), NLOG, fp);
202 	for (lp = &log[n]; lp < &log[NLOG]; lp++)
203 		lp->l_name[0] = lp->l_uid = lp->l_shipnum
204 			= lp->l_gamenum = lp->l_netpoints = 0;
205 	rewind(fp);
206 	if (persons < 0)
207 		putw(1, fp);
208 	else
209 		putw(persons + 1, fp);
210 	for (lp = log; lp < &log[NLOG]; lp++)
211 		if (net > (float)lp->l_netpoints
212 		    / scene[lp->l_gamenum].ship[lp->l_shipnum].specs->pts) {
213 			fwrite((char *)log,
214 				sizeof (struct logs), lp - log, fp);
215 			strcpy(log[NLOG-1].l_name, s->file->captain);
216 			log[NLOG-1].l_uid = getuid();
217 			log[NLOG-1].l_shipnum = s->file->index;
218 			log[NLOG-1].l_gamenum = game;
219 			log[NLOG-1].l_netpoints = s->file->points;
220 			fwrite((char *)&log[NLOG-1],
221 				sizeof (struct logs), 1, fp);
222 			fwrite((char *)lp,
223 				sizeof (struct logs), &log[NLOG-1] - lp, fp);
224 			break;
225 		}
226 #ifdef LOCK_EX
227 	flock(fileno(fp), LOCK_UN);
228 #endif
229 	fclose(fp);
230 }
231