src/streams.c

   1 /*
   2  * File: streams.c
   3  * Purpose: Used by dungeon generation. This file holds all the
   4  * functions that are applied to a level after the rest has been
   5  * generated, ie streams and level destruction.
   6  */
   7
   8 /*
   9  * Copyright (c) 1989 James E. Wilson, Robert A. Koeneke
  10  *
  11  * This software may be copied and distributed for educational, research, and
  12  * not for profit purposes provided that this copyright and statement are
  13  * included in all such copies.
  14  */
  15
  16 #include "angband.h"
  17 #include "generate.h"
  18 #include "streams.h"
  19 #include "grid.h"
  20
  21
  22 /*
  23  * Recursive fractal algorithm to place water through the dungeon.
  24  */
  25 static void recursive_river(int x1, int y1, int x2, int y2, int feat1, int feat2, int width)
  26 {
  27         int dx, dy, length, l, x, y;
  28         int changex, changey;
  29         int ty, tx;
  30         bool done;
  31         cave_type *c_ptr;
  32
  33         length = distance(x1, y1, x2, y2);
  34
  35         if (length > 4)
  36         {
  37                 /*
  38                  * Divide path in half and call routine twice.
  39                  * There is a small chance of splitting the river
  40                  */
  41                 dx = (x2 - x1) / 2;
  42                 dy = (y2 - y1) / 2;
  43
  44                 if (dy != 0)
  45                 {
  46                         /* perturbation perpendicular to path */
  47                         changex = randint(abs(dy)) * 2 - abs(dy);
  48                 }
  49                 else
  50                 {
  51                         changex = 0;
  52                 }
  53
  54                 if (dx != 0)
  55                 {
  56                         /* perturbation perpendicular to path */
  57                         changey = randint(abs(dx)) * 2 - abs(dx);
  58                 }
  59                 else
  60                 {
  61                         changey = 0;
  62                 }
  63
  64                 if (!in_bounds(y1 + dy + changey, x1 + dx + changex))
  65                 {
  66                         changex = 0;
  67                         changey = 0;
  68                 }
  69
  70                 /* construct river out of two smaller ones */
  71                 recursive_river(x1, y1, x1 + dx + changex, y1 + dy + changey, feat1, feat2, width);
  72                 recursive_river(x1 + dx + changex, y1 + dy + changey, x2, y2, feat1, feat2, width);
  73
  74                 /* Split the river some of the time - junctions look cool */
  75                 if ((randint(DUN_WAT_CHG) == 1) && (width > 0))
  76                 {
  77                         recursive_river(x1 + dx + changex, y1 + dy + changey,
  78                                         x1 + 8 * (dx + changex), y1 + 8 * (dy + changey),
  79                                         feat1, feat2, width - 1);
  80                 }
  81         }
  82         else
  83         {
  84                 /* Actually build the river */
  85                 for (l = 0; l < length; l++)
  86                 {
  87                         x = x1 + l * (x2 - x1) / length;
  88                         y = y1 + l * (y2 - y1) / length;
  89
  90                         done = FALSE;
  91
  92                         while (!done)
  93                         {
  94                                 for (ty = y - width - 1; ty <= y + width + 1; ty++)
  95                                 {
  96                                         for (tx = x - width - 1; tx <= x + width + 1; tx++)
  97                                         {
  98                                                 if (!in_bounds(ty, tx)) continue;
  99
 100                                                 c_ptr = &cave[ty][tx];
 101
 102                                                 if (c_ptr->feat == feat1) continue;
 103                                                 if (c_ptr->feat == feat2) continue;
 104
 105                                                 if (distance(ty, tx, y, x) > rand_spread(width, 1)) continue;
 106
 107                                                 /* Do not convert permanent features */
 108                                                 if (cave_perma_grid(c_ptr) && (c_ptr->feat != FEAT_MOUNTAIN)) continue;
 109
 110                                                 /*
 111                                                  * Clear previous contents, add feature
 112                                                  * The border mainly gets feat2, while the center gets feat1
 113                                                  */
 114                                                 if (distance(ty, tx, y, x) > width)
 115                                                         c_ptr->feat = feat2;
 116                                                 else
 117                                                         c_ptr->feat = feat1;
 118
 119                                                 /* Lava terrain glows */
 120                                                 if ((feat1 == FEAT_DEEP_LAVA) ||  (feat1 == FEAT_SHAL_LAVA))
 121                                                 {
 122                                                         c_ptr->info |= CAVE_GLOW;
 123                                                 }
 124
 125                                                 /* Hack -- don't teleport here */
 126                                                 c_ptr->info |= CAVE_ICKY;
 127                                         }
 128                                 }
 129
 130                                 done = TRUE;
 131                         }
 132                 }
 133         }
 134 }
 135
 136
 137 /*
 138  * Places water /lava through dungeon.
 139  */
 140 void add_river(int feat1, int feat2)
 141 {
 142         int y2, x2;
 143         int y1 = 0, x1 = 0;
 144         int wid;
 145
 146
 147         /* Hack -- Choose starting point */
 148         y2 = randint(cur_hgt / 2 - 2) + cur_hgt / 2;
 149         x2 = randint(cur_wid / 2 - 2) + cur_wid / 2;
 150
 151         /* Hack -- Choose ending point somewhere on boundary */
 152         switch(randint(4))
 153         {
 154                 case 1:
 155                 {
 156                         /* top boundary */
 157                         x1 = randint(cur_wid-2)+1;
 158                         y1 = 1;
 159                         break;
 160                 }
 161                 case 2:
 162                 {
 163                         /* left boundary */
 164                         x1 = 1;
 165                         y1 = randint(cur_hgt-2)+1;
 166                         break;
 167                 }
 168                 case 3:
 169                 {
 170                         /* right boundary */
 171                         x1 = cur_wid-1;
 172                         y1 = randint(cur_hgt-2)+1;
 173                         break;
 174                 }
 175                 case 4:
 176                 {
 177                         /* bottom boundary */
 178                         x1 = randint(cur_wid-2)+1;
 179                         y1 = cur_hgt-1;
 180                         break;
 181                 }
 182         }
 183
 184         wid = randint(DUN_WAT_RNG);
 185         recursive_river(x1, y1, x2, y2, feat1, feat2, wid);
 186
 187         /* Hack - Save the location as a "room" */
 188         if (dun->cent_n < CENT_MAX)
 189         {
 190                 dun->cent[dun->cent_n].y = y2;
 191                 dun->cent[dun->cent_n].x = x2;
 192                 dun->cent_n++;
 193         }
 194 }
 195
 196
 197 /*
 198  * Places "streamers" of rock through dungeon
 199  *
 200  * Note that their are actually six different terrain features used
 201  * to represent streamers.  Three each of magma and quartz, one for
 202  * basic vein, one with hidden gold, and one with known gold.  The
 203  * hidden gold types are currently unused.
 204  */
 205 void build_streamer(int feat, int chance)
 206 {
 207         int             i, tx, ty;
 208         int             y, x, dir;
 209         int dummy = 0;
 210         bool treasure = FALSE;
 211
 212         cave_type *c_ptr;
 213
 214         /* Hack -- Choose starting point */
 215         y = rand_spread(cur_hgt / 2, 10);
 216         x = rand_spread(cur_wid / 2, 15);
 217
 218         /* Choose a random compass direction */
 219         dir = ddd[rand_int(8)];
 220
 221         /* Place streamer into dungeon */
 222         while (dummy < SAFE_MAX_ATTEMPTS)
 223         {
 224                 dummy++;
 225
 226                 /* One grid per density */
 227                 for (i = 0; i < DUN_STR_DEN; i++)
 228                 {
 229                         int d = DUN_STR_RNG;
 230
 231                         /* Pick a nearby grid */
 232                         while (1)
 233                         {
 234                                 ty = rand_spread(y, d);
 235                                 tx = rand_spread(x, d);
 236                                 if (!in_bounds(ty, tx)) continue;
 237                                 break;
 238                         }
 239
 240                         /* Access the grid */
 241                         c_ptr = &cave[ty][tx];
 242
 243                         if ((c_ptr->feat >= FEAT_DEEP_WATER) && (c_ptr->feat <= FEAT_SHAL_LAVA)) continue;
 244                         if ((c_ptr->feat >= FEAT_PERM_EXTRA) && (c_ptr->feat <= FEAT_PERM_SOLID)) continue;
 245
 246                         /* Only convert "granite" walls */
 247                         if ((feat >= FEAT_MAGMA) && (feat <= FEAT_WALL_SOLID))
 248                         {
 249                                 if (!is_extra_grid(c_ptr) && !is_inner_grid(c_ptr) && !is_outer_grid(c_ptr) && !is_solid_grid(c_ptr)) continue;
 250                                 if ((c_ptr->feat >= FEAT_DOOR_HEAD) && (c_ptr->feat <= FEAT_SECRET)) continue;
 251                                 if ((feat == FEAT_MAGMA) || (feat == FEAT_QUARTZ)) treasure = TRUE;
 252                         }
 253                         else
 254                         {
 255                                 if (cave_perma_grid(c_ptr) && (c_ptr->feat != FEAT_MOUNTAIN)) continue;
 256                         }
 257
 258                         /* Clear previous contents, add proper vein type */
 259                         c_ptr->feat = feat;
 260
 261                         /* Hack -- Add some (known) treasure */
 262                         if (treasure && (rand_int(chance) == 0)) c_ptr->feat += 0x04;
 263                 }
 264
 265                 if (dummy >= SAFE_MAX_ATTEMPTS)
 266                 {
 267                         if (cheat_room)
 268                         {
 269 #ifdef JP
 270 msg_print("·Ù¹ð¡ª¥¹¥È¥ê¡¼¥Þ¡¼¤òÇÛÃÖ¤Ç¤¤Þ¤»¤ó¡ª");
 271 #else
 272                                 msg_print("Warning! Could not place streamer!");
 273 #endif
 274
 275                         }
 276                         return;
 277                 }
 278
 279
 280                 /* Advance the streamer */
 281                 y += ddy[dir];
 282                 x += ddx[dir];
 283
 284                 /* Quit before leaving the dungeon */
 285                 if (!in_bounds(y, x)) break;
 286         }
 287 }
 288
 289
 290 /*
 291  * Put trees near a hole in the dungeon roof  (rubble on ground + up stairway)
 292  * This happens in real world lava tubes.
 293  */
 294 void place_trees(int x, int y)
 295 {
 296         int i, j;
 297         cave_type *c_ptr;
 298
 299         /* place trees/ rubble in ovalish distribution */
 300         for (i = x - 3; i < x + 4; i++)
 301         {
 302                 for (j = y - 3; j < y + 4; j++)
 303                 {
 304                         if (!in_bounds(j, i)) continue;
 305                         c_ptr = &cave[j][i];
 306
 307                         if (c_ptr->info & CAVE_ICKY) continue;
 308                         if (c_ptr->info & CAVE_TRAP) continue;
 309                         if (c_ptr->o_idx) continue;
 310
 311                         /* Want square to be in the circle and accessable. */
 312                         if ((distance(j, i, y, x) < 4) && !cave_perma_grid(c_ptr))
 313                         {
 314                                 /*
 315                                  * Clear previous contents, add feature
 316                                  * The border mainly gets trees, while the center gets rubble
 317                                  */
 318                                 if ((distance(j, i, y, x) > 1) || (randint(100) < 25))
 319                                 {
 320                                         if (randint(100) < 75)
 321                                                 cave[j][i].feat = FEAT_TREES;
 322                                 }
 323                                 else
 324                                 {
 325                                         cave[j][i].feat = FEAT_RUBBLE;
 326                                 }
 327
 328                                 /* Light area since is open above */
 329                                 cave[j][i].info |= (CAVE_GLOW | CAVE_ROOM);
 330                         }
 331                 }
 332         }
 333
 334         /* No up stairs in ironman mode */
 335         if (!ironman_downward && (randint(3) == 1))
 336         {
 337                 /* up stair */
 338                 cave[y][x].feat = FEAT_LESS;
 339         }
 340 }
 341
 342
 343 /*
 344  * Build a destroyed level
 345  */
 346 void destroy_level(void)
 347 {
 348         int y1, x1, y, x, k, t, n;
 349
 350         cave_type *c_ptr;
 351
 352         /* Note destroyed levels */
 353 #ifdef JP
 354 if (cheat_room) msg_print("ÇË²õ¤µ¤ì¤¿³¬");
 355 #else
 356         if (cheat_room) msg_print("Destroyed Level");
 357 #endif
 358
 359
 360         /* Drop a few epi-centers (usually about two) */
 361         for (n = 0; n < randint(5); n++)
 362         {
 363                 /* Pick an epi-center */
 364                 x1 = rand_range(5, cur_wid - 1 - 5);
 365                 y1 = rand_range(5, cur_hgt - 1 - 5);
 366
 367                 /* Big area of affect */
 368                 for (y = (y1 - 15); y <= (y1 + 15); y++)
 369                 {
 370                         for (x = (x1 - 15); x <= (x1 + 15); x++)
 371                         {
 372                                 /* Skip illegal grids */
 373                                 if (!in_bounds(y, x)) continue;
 374
 375                                 /* Extract the distance */
 376                                 k = distance(y1, x1, y, x);
 377
 378                                 /* Stay in the circle of death */
 379                                 if (k >= 16) continue;
 380
 381                                 /* Delete the monster (if any) */
 382                                 delete_monster(y, x);
 383
 384                                 /* Access the grid */
 385                                 c_ptr = &cave[y][x];
 386
 387                                 /* Destroy valid grids */
 388                                 if (cave_valid_grid(c_ptr))
 389                                 {
 390                                         /* Delete objects */
 391                                         delete_object(y, x);
 392
 393                                         /* Wall (or floor) type */
 394                                         t = rand_int(200);
 395
 396                                         /* Granite */
 397                                         if (t < 20)
 398                                         {
 399                                                 /* Create granite wall */
 400                                                 place_extra_grid(c_ptr);
 401                                         }
 402
 403                                         /* Quartz */
 404                                         else if (t < 70)
 405                                         {
 406                                                 /* Create quartz vein */
 407                                                 c_ptr->feat = FEAT_QUARTZ;
 408                                         }
 409
 410                                         /* Magma */
 411                                         else if (t < 100)
 412                                         {
 413                                                 /* Create magma vein */
 414                                                 c_ptr->feat = FEAT_MAGMA;
 415                                         }
 416
 417                                         /* Floor */
 418                                         else
 419                                         {
 420                                                 /* Create floor */
 421                                                 place_floor_grid(c_ptr);
 422                                         }
 423
 424                                         /* No longer part of a room or vault */
 425                                         c_ptr->info &= ~(CAVE_ROOM | CAVE_ICKY);
 426
 427                                         /* No longer illuminated or known */
 428                                         c_ptr->info &= ~(CAVE_MARK | CAVE_GLOW);
 429                                 }
 430                         }
 431                 }
 432         }
 433 }