2 * Empire - A multi-player, client/server Internet based war game.
3 * Copyright (C) 1986-2020, Dave Pare, Jeff Bailey, Thomas Ruschak,
4 * Ken Stevens, Steve McClure, Markus Armbruster
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.
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.
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/>.
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.
27 * paths.c: Routines associated with paths, directions, etc.
29 * Known contributors to this file:
30 * Markus Armbruster, 2005-2020
38 #include "prototypes.h"
42 chkdir(char dir_char, int min_dir, int max_dir)
46 for (i = min_dir; i <= max_dir; i++)
47 if (dir_char == dirch[i])
53 direrr(char *stop_msg, char *view_msg, char *map_msg)
55 pr("Legal directions are:\n");
56 pr(" %c %c\n", dirch[DIR_UL], dirch[DIR_UR]);
57 pr("%c %c\n", dirch[DIR_L], dirch[DIR_R]);
58 pr(" %c %c\n", dirch[DIR_DL], dirch[DIR_DR]);
60 pr(stop_msg, dirch[DIR_STOP]);
62 pr(view_msg, dirch[DIR_VIEW]);
64 pr(map_msg, dirch[DIR_MAP]);
68 * Map direction @dir to a direction index DIR_STOP..DIR_LAST.
69 * @dir must be a valid direction.
74 unsigned i = dir - 'a';
76 if (CANT_HAPPEN(i >= ARRAY_SIZE(dirindex)
83 * return pointer to path; prompt user until a stop char
84 * or a bomb char have been entered. A "bomb" char in
85 * this context is actually "execute" for the partial
86 * move commands, and isn't valid for those commands
87 * which do not accept partial moves.
90 getpath(char *buf, char *arg, coord x, coord y, int onlyown, int showdes,
104 strncpy(buf, arg, MAX_PATH_LEN - 1);
105 buf[MAX_PATH_LEN - 1] = 0;
110 getsect(x, y, §);
114 if (sarg_xy(p, &dx, &dy)) {
115 if (path_find(x, y, dx, dy, player->cnum, mobtype) < 0) {
116 pr("Can't get to %s from here!\n",
117 xyas(dx, dy, player->cnum));
120 len = path_find_route(p, buf + MAX_PATH_LEN - p, x, y, dx, dy);
121 if (p + len >= buf + MAX_PATH_LEN) {
122 pr("Can't handle path to %s, it's too long, sorry.\n",
123 xyas(dx, dy, player->cnum));
126 pr("Using best path '%s'\n", p);
127 pr("Using total path '%s'\n", buf);
130 dir = chkdir(*p, DIR_STOP, DIR_LAST);
132 pr("\"%c\" is not legal...", *p);
133 direrr("'%c' to stop\n", NULL, NULL);
136 nx = x + diroff[dir][0];
137 ny = y + diroff[dir][1];
138 getsect(nx, ny, §);
139 if (onlyown && sect.sct_own != player->cnum) {
140 pr("You don't own %s; you can't go there!\n",
141 xyas(nx, ny, player->cnum));
144 if (dir == DIR_STOP) {
154 getsect(x, y, §);
155 sprintf(prompt, "<%c: %s> ", dchr[sect.sct_type].d_mnem,
156 xyas(x, y, player->cnum));
158 sprintf(prompt, "<%d: %s> ", (int)(p - buf),
159 xyas(x, y, player->cnum));
161 bp = getstring(prompt, buf2);
164 if (p + strlen(bp) + 1 >= buf + MAX_PATH_LEN) {
165 pr("Path length may not exceed %d.\n", MAX_PATH_LEN);
172 return buf[0] ? buf : NULL;
180 fcost(struct sctstr *sp, natid own)
190 ncost(struct sctstr *sp, natid own)
196 * return end x,y of path, and the base
197 * movement cost it takes to get there.
200 pathtoxy(char *path, coord *xp, coord *yp,
201 double (*cost)(struct sctstr *, natid))
213 for (pp = path; *pp; pp++) {
214 if ((val = diridx(*pp)) == DIR_STOP)
218 if (!getsect(x, y, &s))
220 m += cost(&s, s.sct_own);
228 pathrange(coord cx, coord cy, char *pp, int border, struct range *range)
230 int dir, lx, ly, hx, hy;
238 cx += diroff[dir][0];
239 cy += diroff[dir][1];
255 range->lx = xnorm(lx);
256 range->hx = xnorm(hx - lx < WORLD_X ? hx : lx - 1);
257 range->ly = ynorm(ly);
258 range->hy = ynorm(hy - ly < WORLD_Y ? hy : ly - 1);