1 /*
2 * Empire - A multi-player, client/server Internet based war game.
3 * Copyright (C) 1986-2021, Dave Pare, Jeff Bailey, Thomas Ruschak,
4 * Ken Stevens, Steve McClure, Markus Armbruster
5 *
6 * Empire is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 *
19 * ---
20 *
21 * See files README, COPYING and CREDITS in the root of the source
22 * tree for related information and legal notices. It is expected
23 * that future projects/authors will amend these files as needed.
24 *
25 * ---
26 *
27 * fallout.c: Nuclear fallout
28 *
29 * Known contributors to this file:
30 * Dave Pare, 1986
31 * Steve McClure, 1997
32 * Markus Armbruster, 2004-2016
33 */
34
35 #include <config.h>
36
37 #include "chance.h"
38 #include "optlist.h"
39 #include "land.h"
40 #include "ship.h"
41 #include "path.h"
42 #include "prototypes.h"
43 #include "update.h"
44
45 static void do_fallout(struct sctstr *, int);
46 static void meltitems(int, int, int, short *, int, int, int, int);
47 static void spread_fallout(struct sctstr *, int);
48 static void decay_fallout(struct sctstr *, int);
49
50 void
fallout(int etu)51 fallout(int etu)
52 {
53 int n;
54 struct sctstr *sp;
55
56 if (!opt_FALLOUT)
57 return;
58
59 /* First, we determine which sectors to process fallout in */
60 for (n = 0; NULL != (sp = getsectid(n)); n++)
61 sp->sct_updated = sp->sct_fallout != 0;
62 /* Next, we process the fallout there */
63 for (n = 0; NULL != (sp = getsectid(n)); n++)
64 if (sp->sct_updated && sp->sct_type != SCT_SANCT)
65 do_fallout(sp, etu);
66 /* Next, we spread the fallout */
67 for (n = 0; NULL != (sp = getsectid(n)); n++)
68 if (sp->sct_updated)
69 spread_fallout(sp, etu);
70 /* Next, we decay the fallout */
71 for (n = 0; NULL != (sp = getsectid(n)); n++) {
72 if (sp->sct_fallout)
73 decay_fallout(sp, etu);
74 sp->sct_updated = 0;
75 }
76 }
77
78 /*
79 * Do fallout meltdown for sector @sp.
80 * @etus above 24 are treated as 24 to avoid *huge* kill offs in
81 * large ETU games.
82 */
83 static void
do_fallout(struct sctstr * sp,int etus)84 do_fallout(struct sctstr *sp, int etus)
85 {
86 struct shpstr *spp;
87 struct lndstr *lp;
88 int i;
89
90 /* This check shouldn't be needed, but just in case. :) */
91 if (!sp->sct_fallout || !sp->sct_updated)
92 return;
93 if (etus > 24)
94 etus = 24;
95 meltitems(etus, sp->sct_fallout, sp->sct_own, sp->sct_item,
96 EF_SECTOR, sp->sct_x, sp->sct_y, 0);
97 for (i = 0; NULL != (lp = getlandp(i)); i++) {
98 if (!lp->lnd_own)
99 continue;
100 if (lp->lnd_x != sp->sct_x || lp->lnd_y != sp->sct_y)
101 continue;
102 meltitems(etus, sp->sct_fallout, lp->lnd_own, lp->lnd_item,
103 EF_LAND, lp->lnd_x, lp->lnd_y, lp->lnd_uid);
104 }
105 for (i = 0; NULL != (spp = getshipp(i)); i++) {
106 if (!spp->shp_own)
107 continue;
108 if (spp->shp_x != sp->sct_x || spp->shp_y != sp->sct_y)
109 continue;
110 if (mchr[(int)spp->shp_type].m_flags & M_SUB)
111 continue;
112 meltitems(etus, sp->sct_fallout, spp->shp_own, spp->shp_item,
113 EF_SHIP, spp->shp_x, spp->shp_y, spp->shp_uid);
114 }
115 }
116
117 static void
meltitems(int etus,int fallout,int own,short * vec,int type,int x,int y,int uid)118 meltitems(int etus, int fallout, int own, short *vec,
119 int type, int x, int y, int uid)
120 {
121 i_type n;
122 int melt;
123
124 for (n = I_NONE + 1; n <= I_MAX; n++) {
125 melt = roundavg(vec[n] * etus * (double)fallout
126 / (1000.0 * ichr[n].i_melt_denom));
127 if (melt > vec[n])
128 melt = vec[n];
129 if (melt > 5 && own) {
130 if (type == EF_SECTOR)
131 wu(0, own, "Lost %d %s to radiation in %s.\n",
132 melt, ichr[n].i_name,
133 xyas(x, y, own));
134 else if (type == EF_LAND)
135 wu(0, own, "Unit #%d lost %d %s to radiation in %s.\n",
136 uid, melt, ichr[n].i_name,
137 xyas(x, y, own));
138 else if (type == EF_SHIP)
139 wu(0, own, "Ship #%d lost %d %s to radiation in %s.\n",
140 uid, melt, ichr[n].i_name,
141 xyas(x, y, own));
142 }
143 vec[n] -= melt;
144 }
145 }
146
147 static void
spread_fallout(struct sctstr * sp,int etus)148 spread_fallout(struct sctstr *sp, int etus)
149 {
150 struct sctstr *ap;
151 int n;
152 int inc;
153
154 if (etus > 24)
155 etus = 24;
156 for (n = DIR_FIRST; n <= DIR_LAST; n++) {
157 ap = getsectp(sp->sct_x + diroff[n][0], sp->sct_y + diroff[n][1]);
158 if (ap->sct_type == SCT_SANCT)
159 continue;
160 inc = roundavg(etus * fallout_spread * (sp->sct_fallout)) - 1;
161 if (inc < 0)
162 inc = 0;
163 ap->sct_fallout = MIN(ap->sct_fallout + inc, FALLOUT_MAX);
164 }
165 }
166
167 static void
decay_fallout(struct sctstr * sp,int etus)168 decay_fallout(struct sctstr *sp, int etus)
169 {
170 int decay;
171
172 if (etus > 24)
173 etus = 24;
174 decay = roundavg((decay_per_etu + 6.0) * fallout_spread *
175 (double)etus * (double)sp->sct_fallout);
176
177 sp->sct_fallout = decay < sp->sct_fallout ? sp->sct_fallout - decay : 0;
178 }
179