xref: /dragonfly/games/trek/torped.c (revision 0cfebe3d)
1 /*
2  * Copyright (c) 1980, 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. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * @(#)torped.c	8.1 (Berkeley) 5/31/93
34  * $FreeBSD: src/games/trek/torped.c,v 1.5 1999/11/30 03:49:55 billf Exp $
35  * $DragonFly: src/games/trek/torped.c,v 1.3 2006/09/07 21:19:44 pavalos Exp $
36  */
37 
38 # include	"getpar.h"
39 # include	"trek.h"
40 
41 static int	randcourse(int);
42 
43 /*
44 **  PHOTON TORPEDO CONTROL
45 **
46 **	Either one or three photon torpedoes are fired.  If three
47 **	are fired, it is called a "burst" and you also specify
48 **	a spread angle.
49 **
50 **	Torpedoes are never 100% accurate.  There is always a random
51 **	cludge factor in their course which is increased if you have
52 **	your shields up.  Hence, you will find that they are more
53 **	accurate at close range.  However, they have the advantage that
54 **	at long range they don't lose any of their power as phasers
55 **	do, i.e., a hit is a hit is a hit, by any other name.
56 **
57 **	When the course spreads too much, you get a misfire, and the
58 **	course is randomized even more.  You also have the chance that
59 **	the misfire damages your torpedo tubes.
60 */
61 
62 void
63 torped(__unused int unused)
64 {
65 	int		ix, iy;
66 	double			x, y, dx, dy;
67 	double			angle;
68 	int			course, course2;
69 	int		k;
70 	double			bigger;
71 	double			sectsize;
72 	int			burst;
73 	int			n;
74 
75 	if (Ship.cloaked)
76 	{
77 		printf("Federation regulations do not permit attack while cloaked.\n");
78 		return;
79 	}
80 	if (check_out(TORPED))
81 		return;
82 	if (Ship.torped <= 0)
83 	{
84 		printf("All photon torpedos expended\n");
85 		return;
86 	}
87 
88 	/* get the course */
89 	course = getintpar("Torpedo course");
90 	if (course < 0 || course > 360)
91 		return;
92 	burst = -1;
93 
94 	/* need at least three torpedoes for a burst */
95 	if (Ship.torped < 3)
96 	{
97 		printf("No-burst mode selected\n");
98 		burst = 0;
99 	}
100 	else
101 	{
102 		/* see if the user wants one */
103 		if (!testnl())
104 		{
105 			k = ungetc(cgetc(0), stdin);
106 			if (k >= '0' && k <= '9')
107 				burst = 1;
108 		}
109 	}
110 	if (burst < 0)
111 	{
112 		burst = getynpar("Do you want a burst");
113 	}
114 	if (burst)
115 	{
116 		burst = getintpar("burst angle");
117 		if (burst <= 0)
118 			return;
119 		if (burst > 15) {
120 			printf("Maximum burst angle is 15 degrees\n");
121 			return;
122 		}
123 	}
124 	sectsize = NSECTS;
125 	n = -1;
126 	if (burst)
127 	{
128 		n = 1;
129 		course -= burst;
130 	}
131 	for (; n && n <= 3; n++)
132 	{
133 		/* select a nice random course */
134 		course2 = course + randcourse(n);
135 		angle = course2 * 0.0174532925;			/* convert to radians */
136 		dx = -cos(angle);
137 		dy =  sin(angle);
138 		bigger = fabs(dx);
139 		x = fabs(dy);
140 		if (x > bigger)
141 			bigger = x;
142 		dx /= bigger;
143 		dy /= bigger;
144 		x = Ship.sectx + 0.5;
145 		y = Ship.secty + 0.5;
146 		if (Ship.cond != DOCKED)
147 			Ship.torped -= 1;
148 		printf("Torpedo track");
149 		if (n > 0)
150 			printf(", torpedo number %d", n);
151 		printf(":\n%6.1f\t%4.1f\n", x, y);
152 		while (1)
153 		{
154 			ix = x += dx;
155 			iy = y += dy;
156 			if (x < 0.0 || x >= sectsize || y < 0.0 || y >= sectsize)
157 			{
158 				printf("Torpedo missed\n");
159 				break;
160 			}
161 			printf("%6.1f\t%4.1f\n", x, y);
162 			switch (Sect[ix][iy])
163 			{
164 			  case EMPTY:
165 				continue;
166 
167 			  case HOLE:
168 				printf("Torpedo disappears into a black hole\n");
169 				break;
170 
171 			  case KLINGON:
172 				for (k = 0; k < Etc.nkling; k++)
173 				{
174 					if (Etc.klingon[k].x != ix || Etc.klingon[k].y != iy)
175 						continue;
176 					Etc.klingon[k].power -= 500 + ranf(501);
177 					if (Etc.klingon[k].power > 0)
178 					{
179 						printf("*** Hit on Klingon at %d,%d: extensive damages\n",
180 							ix, iy);
181 						break;
182 					}
183 					killk(ix, iy);
184 					break;
185 				}
186 				break;
187 
188 			  case STAR:
189 				nova(ix, iy);
190 				break;
191 
192 			  case INHABIT:
193 				kills(ix, iy, -1);
194 				break;
195 
196 			  case BASE:
197 				killb(Ship.quadx, Ship.quady);
198 				Game.killb += 1;
199 				break;
200 			  default:
201 				printf("Unknown object %c at %d,%d destroyed\n",
202 					Sect[ix][iy], ix, iy);
203 				Sect[ix][iy] = EMPTY;
204 				break;
205 			}
206 			break;
207 		}
208 		if (damaged(TORPED) || Quad[Ship.quadx][Ship.quady].stars < 0)
209 			break;
210 		course += burst;
211 	}
212 	Move.free = 0;
213 }
214 
215 
216 /*
217 **  RANDOMIZE COURSE
218 **
219 **	This routine randomizes the course for torpedo number 'n'.
220 **	Other things handled by this routine are misfires, damages
221 **	to the tubes, etc.
222 */
223 
224 static int
225 randcourse(int n)
226 {
227 	double			r;
228 	int		d;
229 
230 	d = ((franf() + franf()) - 1.0) * 20;
231 	if (abs(d) > 12)
232 	{
233 		printf("Photon tubes misfire");
234 		if (n < 0)
235 			printf("\n");
236 		else
237 			printf(" on torpedo %d\n", n);
238 		if (ranf(2))
239 		{
240 			damage(TORPED, 0.2 * abs(d) * (franf() + 1.0));
241 		}
242 		d *= 1.0 + 2.0 * franf();
243 	}
244 	if (Ship.shldup || Ship.cond == DOCKED)
245 	{
246 		r = Ship.shield;
247 		r = 1.0 + r / Param.shield;
248 		if (Ship.cond == DOCKED)
249 			r = 2.0;
250 		d *= r;
251 	}
252 	return (d);
253 }
254