makemaze.c revision 1.3
1 /* $NetBSD: makemaze.c,v 1.3 2003/06/11 12:00:22 wiz Exp $ */ 2 /* 3 * Copyright (c) 1983-2003, Regents of the University of California. 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions are 8 * met: 9 * 10 * + Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * + 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 * + Neither the name of the University of California, San Francisco nor 16 * the names of its contributors may be used to endorse or promote 17 * products derived from this software without specific prior written 18 * permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS 21 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A 23 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 24 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 25 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 26 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 30 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 #include <sys/cdefs.h> 34 #ifndef lint 35 __RCSID("$NetBSD: makemaze.c,v 1.3 2003/06/11 12:00:22 wiz Exp $"); 36 #endif /* not lint */ 37 38 # include "hunt.h" 39 40 # define ISCLEAR(y,x) (Maze[y][x] == SPACE) 41 # define ODD(n) ((n) & 01) 42 43 static int candig __P((int, int)); 44 static void dig __P((int, int)); 45 static void dig_maze __P((int, int)); 46 static void remap __P((void)); 47 48 void 49 makemaze() 50 { 51 char *sp; 52 int y, x; 53 54 /* 55 * fill maze with walls 56 */ 57 sp = &Maze[0][0]; 58 while (sp < &Maze[HEIGHT - 1][WIDTH]) 59 *sp++ = DOOR; 60 61 x = rand_num(WIDTH / 2) * 2 + 1; 62 y = rand_num(HEIGHT / 2) * 2 + 1; 63 dig_maze(x, y); 64 remap(); 65 } 66 67 # define NPERM 24 68 # define NDIR 4 69 70 int dirs[NPERM][NDIR] = { 71 {0,1,2,3}, {3,0,1,2}, {0,2,3,1}, {0,3,2,1}, 72 {1,0,2,3}, {2,3,0,1}, {0,2,1,3}, {2,3,1,0}, 73 {1,0,3,2}, {1,2,0,3}, {3,1,2,0}, {2,0,3,1}, 74 {1,3,0,2}, {0,3,1,2}, {1,3,2,0}, {2,0,1,3}, 75 {0,1,3,2}, {3,1,0,2}, {2,1,0,3}, {1,2,3,0}, 76 {2,1,3,0}, {3,0,2,1}, {3,2,0,1}, {3,2,1,0} 77 }; 78 79 int incr[NDIR][2] = { 80 {0, 1}, {1, 0}, {0, -1}, {-1, 0} 81 }; 82 83 static void 84 dig(y, x) 85 int y, x; 86 { 87 int *dp; 88 int *ip; 89 int ny, nx; 90 int *endp; 91 92 Maze[y][x] = SPACE; /* Clear this spot */ 93 dp = dirs[rand_num(NPERM)]; 94 endp = &dp[NDIR]; 95 while (dp < endp) { 96 ip = &incr[*dp++][0]; 97 ny = y + *ip++; 98 nx = x + *ip; 99 if (candig(ny, nx)) 100 dig(ny, nx); 101 } 102 } 103 104 /* 105 * candig: 106 * Is it legal to clear this spot? 107 */ 108 static int 109 candig(y, x) 110 int y, x; 111 { 112 int i; 113 114 if (ODD(x) && ODD(y)) 115 return FALSE; /* can't touch ODD spots */ 116 117 if (y < UBOUND || y >= DBOUND) 118 return FALSE; /* Beyond vertical bounds, NO */ 119 if (x < LBOUND || x >= RBOUND) 120 return FALSE; /* Beyond horizontal bounds, NO */ 121 122 if (ISCLEAR(y, x)) 123 return FALSE; /* Already clear, NO */ 124 125 i = ISCLEAR(y, x + 1); 126 i += ISCLEAR(y, x - 1); 127 if (i > 1) 128 return FALSE; /* Introduces cycle, NO */ 129 i += ISCLEAR(y + 1, x); 130 if (i > 1) 131 return FALSE; /* Introduces cycle, NO */ 132 i += ISCLEAR(y - 1, x); 133 if (i > 1) 134 return FALSE; /* Introduces cycle, NO */ 135 136 return TRUE; /* OK */ 137 } 138 139 void 140 dig_maze(x, y) 141 int x, y; 142 { 143 int tx, ty; 144 int i, j; 145 int order[4]; 146 #define MNORTH 0x1 147 #define MSOUTH 0x2 148 #define MEAST 0x4 149 #define MWEST 0x8 150 151 tx = ty = 0; 152 Maze[y][x] = SPACE; 153 order[0] = MNORTH; 154 for (i = 1; i < 4; i++) { 155 j = rand_num(i + 1); 156 order[i] = order[j]; 157 order[j] = 0x1 << i; 158 } 159 for (i = 0; i < 4; i++) { 160 switch (order[i]) { 161 case MNORTH: 162 tx = x; 163 ty = y - 2; 164 break; 165 case MSOUTH: 166 tx = x; 167 ty = y + 2; 168 break; 169 case MEAST: 170 tx = x + 2; 171 ty = y; 172 break; 173 case MWEST: 174 tx = x - 2; 175 ty = y; 176 break; 177 } 178 if (tx < 0 || ty < 0 || tx >= WIDTH || ty >= HEIGHT) 179 continue; 180 if (Maze[ty][tx] == SPACE) 181 continue; 182 Maze[(y + ty) / 2][(x + tx) / 2] = SPACE; 183 dig_maze(tx, ty); 184 } 185 } 186 187 void 188 remap() 189 { 190 int y, x; 191 char *sp; 192 int stat; 193 194 for (y = 0; y < HEIGHT; y++) 195 for (x = 0; x < WIDTH; x++) { 196 sp = &Maze[y][x]; 197 if (*sp == SPACE) 198 continue; 199 stat = 0; 200 if (y - 1 >= 0 && Maze[y - 1][x] != SPACE) 201 stat |= NORTH; 202 if (y + 1 < HEIGHT && Maze[y + 1][x] != SPACE) 203 stat |= SOUTH; 204 if (x + 1 < WIDTH && Maze[y][x + 1] != SPACE) 205 stat |= EAST; 206 if (x - 1 >= 0 && Maze[y][x - 1] != SPACE) 207 stat |= WEST; 208 switch (stat) { 209 case WEST | EAST: 210 case EAST: 211 case WEST: 212 *sp = WALL1; 213 break; 214 case NORTH | SOUTH: 215 case NORTH: 216 case SOUTH: 217 *sp = WALL2; 218 break; 219 case 0: 220 # ifdef RANDOM 221 *sp = DOOR; 222 # endif 223 # ifdef REFLECT 224 *sp = rand_num(2) ? WALL4 : WALL5; 225 # endif 226 break; 227 default: 228 *sp = WALL3; 229 break; 230 } 231 } 232 memcpy(Orig_maze, Maze, sizeof Maze); 233 } 234
Indexes created Thu Oct 02 14:10:14 GMT 2025