xref: /netbsd-src/games/trek/klmove.c (revision 61357867d7264ecbe2df9b44f73ef6bdced801b8)
1 /*	$NetBSD: klmove.c,v 1.9 2009/05/24 22:55:03 dholland Exp $	*/
2 
3 /*
4  * Copyright (c) 1980, 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[] = "@(#)klmove.c	8.1 (Berkeley) 5/31/93";
36 #else
37 __RCSID("$NetBSD: klmove.c,v 1.9 2009/05/24 22:55:03 dholland Exp $");
38 #endif
39 #endif /* not lint */
40 
41 #include <stdio.h>
42 #include "trek.h"
43 
44 /*
45 **  Move Klingons Around
46 **
47 **	This is a largely incomprehensible block of code that moves
48 **	Klingons around in a quadrant.  It was written in a very
49 **	"program as you go" fashion, and is a prime candidate for
50 **	rewriting.
51 **
52 **	The flag `fl' is zero before an attack, one after an attack,
53 **	and two if you are leaving a quadrant.  This serves to
54 **	change the probability and distance that it moves.
55 **
56 **	Basically, what it will try to do is to move a certain number
57 **	of steps either toward you or away from you.  It will avoid
58 **	stars whenever possible.  Nextx and nexty are the next
59 **	sector to move to on a per-Klingon basis; they are roughly
60 **	equivalent to Ship.sectx and Ship.secty for the starship.  Lookx and
61 **	looky are the sector that you are going to look at to see
62 **	if you can move their.  Dx and dy are the increment.  Fudgex
63 **	and fudgey are the things you change around to change your
64 **	course around stars.
65 */
66 
67 void
klmove(int fl)68 klmove(int fl)
69 {
70 	int			n;
71 	struct kling	*k;
72 	double			dx, dy;
73 	int			nextx, nexty;
74 	int		lookx, looky;
75 	int			motion;
76 	int			fudgex, fudgey;
77 	int			qx, qy;
78 	double			bigger;
79 	int			i;
80 
81 #ifdef xTRACE
82 	if (Trace)
83 		printf("klmove: fl = %d, Etc.nkling = %d\n", fl, Etc.nkling);
84 #endif
85 	for (n = 0; n < Etc.nkling; n++) {
86 		k = &Etc.klingon[n];
87 		i = 100;
88 		if (fl)
89 			i = 100.0 * k->power / Param.klingpwr;
90 		if (ranf(i) >= Param.moveprob[2 * Move.newquad + fl])
91 			continue;
92 		/* compute distance to move */
93 		motion = ranf(75) - 25;
94 		motion *= k->avgdist * Param.movefac[2 * Move.newquad + fl];
95 		/* compute direction */
96 		dx = Ship.sectx - k->x + ranf(3) - 1;
97 		dy = Ship.secty - k->y + ranf(3) - 1;
98 		bigger = dx;
99 		if (dy > bigger)
100 			bigger = dy;
101 		if (bigger == 0.0)
102 			bigger = 1.0;
103 		dx = dx / bigger + 0.5;
104 		dy = dy / bigger + 0.5;
105 		if (motion < 0) {
106 			motion = -motion;
107 			dx = -dx;
108 			dy = -dy;
109 		}
110 		fudgex = fudgey = 1;
111 		/* try to move the klingon */
112 		nextx = k->x;
113 		nexty = k->y;
114 		for (; motion > 0; motion--) {
115 			lookx = nextx + dx;
116 			looky = nexty + dy;
117 			if (lookx < 0 || lookx >= NSECTS ||
118 			    looky < 0 || looky >= NSECTS) {
119 				/* new quadrant */
120 				qx = Ship.quadx;
121 				qy = Ship.quady;
122 				if (lookx < 0)
123 					qx -= 1;
124 				else
125 					if (lookx >= NSECTS)
126 						qx += 1;
127 				if (looky < 0)
128 					qy -= 1;
129 				else
130 					if (looky >= NSECTS)
131 						qy += 1;
132 				if (qx < 0 || qx >= NQUADS ||
133 				    qy < 0 || qy >= NQUADS ||
134 				    Quad[qx][qy].stars < 0 ||
135 				    Quad[qx][qy].klings > MAXKLQUAD - 1)
136 					break;
137 				if (!damaged(SRSCAN)) {
138 					printf("Klingon at %d,%d escapes to "
139 					       "quadrant %d,%d\n",
140 						k->x, k->y, qx, qy);
141 					motion = Quad[qx][qy].scanned;
142 					if (motion >= 0 && motion < 1000)
143 						Quad[qx][qy].scanned += 100;
144 					motion = Quad[Ship.quadx][Ship.quady]
145 						.scanned;
146 					if (motion >= 0 && motion < 1000)
147 						Quad[Ship.quadx][Ship.quady]
148 							.scanned -= 100;
149 				}
150 				Sect[k->x][k->y] = EMPTY;
151 				Quad[qx][qy].klings += 1;
152 				Etc.nkling -= 1;
153 				*k = Etc.klingon[Etc.nkling];
154 				Quad[Ship.quadx][Ship.quady].klings -= 1;
155 				k = 0;
156 				break;
157 			}
158 			if (Sect[lookx][looky] != EMPTY) {
159 				lookx = nextx + fudgex;
160 				if (lookx < 0 || lookx >= NSECTS)
161 					lookx = nextx + dx;
162 				if (Sect[lookx][looky] != EMPTY) {
163 					fudgex = -fudgex;
164 					looky = nexty + fudgey;
165 					if (looky < 0 || looky >= NSECTS ||
166 					    Sect[lookx][looky] != EMPTY) {
167 						fudgey = -fudgey;
168 						break;
169 					}
170 				}
171 			}
172 			nextx = lookx;
173 			nexty = looky;
174 		}
175 		if (k && (k->x != nextx || k->y != nexty)) {
176 			if (!damaged(SRSCAN))
177 				printf("Klingon at %d,%d moves to %d,%d\n",
178 					k->x, k->y, nextx, nexty);
179 			Sect[k->x][k->y] = EMPTY;
180 			Sect[k->x = nextx][k->y = nexty] = KLINGON;
181 		}
182 	}
183 	compkldist(0);
184 }
185