| 1 | /* |
| 2 | * map.c: Game involving four-colouring a map. |
| 3 | */ |
| 4 | |
| 5 | /* |
| 6 | * TODO: |
| 7 | * |
| 8 | * - clue marking |
| 9 | * - better four-colouring algorithm? |
| 10 | */ |
| 11 | |
| 12 | #include <stdio.h> |
| 13 | #include <stdlib.h> |
| 14 | #include <string.h> |
| 15 | #include <assert.h> |
| 16 | #include <ctype.h> |
| 17 | #include <math.h> |
| 18 | |
| 19 | #include "puzzles.h" |
| 20 | |
| 21 | /* |
| 22 | * In standalone solver mode, `verbose' is a variable which can be |
| 23 | * set by command-line option; in debugging mode it's simply always |
| 24 | * true. |
| 25 | */ |
| 26 | #if defined STANDALONE_SOLVER |
| 27 | #define SOLVER_DIAGNOSTICS |
| 28 | int verbose = FALSE; |
| 29 | #elif defined SOLVER_DIAGNOSTICS |
| 30 | #define verbose TRUE |
| 31 | #endif |
| 32 | |
| 33 | /* |
| 34 | * I don't seriously anticipate wanting to change the number of |
| 35 | * colours used in this game, but it doesn't cost much to use a |
| 36 | * #define just in case :-) |
| 37 | */ |
| 38 | #define FOUR 4 |
| 39 | #define THREE (FOUR-1) |
| 40 | #define FIVE (FOUR+1) |
| 41 | #define SIX (FOUR+2) |
| 42 | |
| 43 | /* |
| 44 | * Ghastly run-time configuration option, just for Gareth (again). |
| 45 | */ |
| 46 | static int flash_type = -1; |
| 47 | static float flash_length; |
| 48 | |
| 49 | /* |
| 50 | * Difficulty levels. I do some macro ickery here to ensure that my |
| 51 | * enum and the various forms of my name list always match up. |
| 52 | */ |
| 53 | #define DIFFLIST(A) \ |
| 54 | A(EASY,Easy,e) \ |
| 55 | A(NORMAL,Normal,n) \ |
| 56 | A(HARD,Hard,h) \ |
| 57 | A(RECURSE,Unreasonable,u) |
| 58 | #define ENUM(upper,title,lower) DIFF_ ## upper, |
| 59 | #define TITLE(upper,title,lower) #title, |
| 60 | #define ENCODE(upper,title,lower) #lower |
| 61 | #define CONFIG(upper,title,lower) ":" #title |
| 62 | enum { DIFFLIST(ENUM) DIFFCOUNT }; |
| 63 | static char const *const map_diffnames[] = { DIFFLIST(TITLE) }; |
| 64 | static char const map_diffchars[] = DIFFLIST(ENCODE); |
| 65 | #define DIFFCONFIG DIFFLIST(CONFIG) |
| 66 | |
| 67 | enum { TE, BE, LE, RE }; /* top/bottom/left/right edges */ |
| 68 | |
| 69 | enum { |
| 70 | COL_BACKGROUND, |
| 71 | COL_GRID, |
| 72 | COL_0, COL_1, COL_2, COL_3, |
| 73 | COL_ERROR, COL_ERRTEXT, |
| 74 | NCOLOURS |
| 75 | }; |
| 76 | |
| 77 | struct game_params { |
| 78 | int w, h, n, diff; |
| 79 | }; |
| 80 | |
| 81 | struct map { |
| 82 | int refcount; |
| 83 | int *map; |
| 84 | int *graph; |
| 85 | int n; |
| 86 | int ngraph; |
| 87 | int *immutable; |
| 88 | int *edgex, *edgey; /* position of a point on each edge */ |
| 89 | int *regionx, *regiony; /* position of a point in each region */ |
| 90 | }; |
| 91 | |
| 92 | struct game_state { |
| 93 | game_params p; |
| 94 | struct map *map; |
| 95 | int *colouring, *pencil; |
| 96 | int completed, cheated; |
| 97 | }; |
| 98 | |
| 99 | static game_params *default_params(void) |
| 100 | { |
| 101 | game_params *ret = snew(game_params); |
| 102 | |
| 103 | ret->w = 20; |
| 104 | ret->h = 15; |
| 105 | ret->n = 30; |
| 106 | ret->diff = DIFF_NORMAL; |
| 107 | |
| 108 | return ret; |
| 109 | } |
| 110 | |
| 111 | static const struct game_params map_presets[] = { |
| 112 | {20, 15, 30, DIFF_EASY}, |
| 113 | {20, 15, 30, DIFF_NORMAL}, |
| 114 | {20, 15, 30, DIFF_HARD}, |
| 115 | {20, 15, 30, DIFF_RECURSE}, |
| 116 | {30, 25, 75, DIFF_NORMAL}, |
| 117 | {30, 25, 75, DIFF_HARD}, |
| 118 | }; |
| 119 | |
| 120 | static int game_fetch_preset(int i, char **name, game_params **params) |
| 121 | { |
| 122 | game_params *ret; |
| 123 | char str[80]; |
| 124 | |
| 125 | if (i < 0 || i >= lenof(map_presets)) |
| 126 | return FALSE; |
| 127 | |
| 128 | ret = snew(game_params); |
| 129 | *ret = map_presets[i]; |
| 130 | |
| 131 | sprintf(str, "%dx%d, %d regions, %s", ret->w, ret->h, ret->n, |
| 132 | map_diffnames[ret->diff]); |
| 133 | |
| 134 | *name = dupstr(str); |
| 135 | *params = ret; |
| 136 | return TRUE; |
| 137 | } |
| 138 | |
| 139 | static void free_params(game_params *params) |
| 140 | { |
| 141 | sfree(params); |
| 142 | } |
| 143 | |
| 144 | static game_params *dup_params(game_params *params) |
| 145 | { |
| 146 | game_params *ret = snew(game_params); |
| 147 | *ret = *params; /* structure copy */ |
| 148 | return ret; |
| 149 | } |
| 150 | |
| 151 | static void decode_params(game_params *params, char const *string) |
| 152 | { |
| 153 | char const *p = string; |
| 154 | |
| 155 | params->w = atoi(p); |
| 156 | while (*p && isdigit((unsigned char)*p)) p++; |
| 157 | if (*p == 'x') { |
| 158 | p++; |
| 159 | params->h = atoi(p); |
| 160 | while (*p && isdigit((unsigned char)*p)) p++; |
| 161 | } else { |
| 162 | params->h = params->w; |
| 163 | } |
| 164 | if (*p == 'n') { |
| 165 | p++; |
| 166 | params->n = atoi(p); |
| 167 | while (*p && (*p == '.' || isdigit((unsigned char)*p))) p++; |
| 168 | } else { |
| 169 | params->n = params->w * params->h / 8; |
| 170 | } |
| 171 | if (*p == 'd') { |
| 172 | int i; |
| 173 | p++; |
| 174 | for (i = 0; i < DIFFCOUNT; i++) |
| 175 | if (*p == map_diffchars[i]) |
| 176 | params->diff = i; |
| 177 | if (*p) p++; |
| 178 | } |
| 179 | } |
| 180 | |
| 181 | static char *encode_params(game_params *params, int full) |
| 182 | { |
| 183 | char ret[400]; |
| 184 | |
| 185 | sprintf(ret, "%dx%dn%d", params->w, params->h, params->n); |
| 186 | if (full) |
| 187 | sprintf(ret + strlen(ret), "d%c", map_diffchars[params->diff]); |
| 188 | |
| 189 | return dupstr(ret); |
| 190 | } |
| 191 | |
| 192 | static config_item *game_configure(game_params *params) |
| 193 | { |
| 194 | config_item *ret; |
| 195 | char buf[80]; |
| 196 | |
| 197 | ret = snewn(5, config_item); |
| 198 | |
| 199 | ret[0].name = "Width"; |
| 200 | ret[0].type = C_STRING; |
| 201 | sprintf(buf, "%d", params->w); |
| 202 | ret[0].sval = dupstr(buf); |
| 203 | ret[0].ival = 0; |
| 204 | |
| 205 | ret[1].name = "Height"; |
| 206 | ret[1].type = C_STRING; |
| 207 | sprintf(buf, "%d", params->h); |
| 208 | ret[1].sval = dupstr(buf); |
| 209 | ret[1].ival = 0; |
| 210 | |
| 211 | ret[2].name = "Regions"; |
| 212 | ret[2].type = C_STRING; |
| 213 | sprintf(buf, "%d", params->n); |
| 214 | ret[2].sval = dupstr(buf); |
| 215 | ret[2].ival = 0; |
| 216 | |
| 217 | ret[3].name = "Difficulty"; |
| 218 | ret[3].type = C_CHOICES; |
| 219 | ret[3].sval = DIFFCONFIG; |
| 220 | ret[3].ival = params->diff; |
| 221 | |
| 222 | ret[4].name = NULL; |
| 223 | ret[4].type = C_END; |
| 224 | ret[4].sval = NULL; |
| 225 | ret[4].ival = 0; |
| 226 | |
| 227 | return ret; |
| 228 | } |
| 229 | |
| 230 | static game_params *custom_params(config_item *cfg) |
| 231 | { |
| 232 | game_params *ret = snew(game_params); |
| 233 | |
| 234 | ret->w = atoi(cfg[0].sval); |
| 235 | ret->h = atoi(cfg[1].sval); |
| 236 | ret->n = atoi(cfg[2].sval); |
| 237 | ret->diff = cfg[3].ival; |
| 238 | |
| 239 | return ret; |
| 240 | } |
| 241 | |
| 242 | static char *validate_params(game_params *params, int full) |
| 243 | { |
| 244 | if (params->w < 2 || params->h < 2) |
| 245 | return "Width and height must be at least two"; |
| 246 | if (params->n < 5) |
| 247 | return "Must have at least five regions"; |
| 248 | if (params->n > params->w * params->h) |
| 249 | return "Too many regions to fit in grid"; |
| 250 | return NULL; |
| 251 | } |
| 252 | |
| 253 | /* ---------------------------------------------------------------------- |
| 254 | * Cumulative frequency table functions. |
| 255 | */ |
| 256 | |
| 257 | /* |
| 258 | * Initialise a cumulative frequency table. (Hardly worth writing |
| 259 | * this function; all it does is to initialise everything in the |
| 260 | * array to zero.) |
| 261 | */ |
| 262 | static void cf_init(int *table, int n) |
| 263 | { |
| 264 | int i; |
| 265 | |
| 266 | for (i = 0; i < n; i++) |
| 267 | table[i] = 0; |
| 268 | } |
| 269 | |
| 270 | /* |
| 271 | * Increment the count of symbol `sym' by `count'. |
| 272 | */ |
| 273 | static void cf_add(int *table, int n, int sym, int count) |
| 274 | { |
| 275 | int bit; |
| 276 | |
| 277 | bit = 1; |
| 278 | while (sym != 0) { |
| 279 | if (sym & bit) { |
| 280 | table[sym] += count; |
| 281 | sym &= ~bit; |
| 282 | } |
| 283 | bit <<= 1; |
| 284 | } |
| 285 | |
| 286 | table[0] += count; |
| 287 | } |
| 288 | |
| 289 | /* |
| 290 | * Cumulative frequency lookup: return the total count of symbols |
| 291 | * with value less than `sym'. |
| 292 | */ |
| 293 | static int cf_clookup(int *table, int n, int sym) |
| 294 | { |
| 295 | int bit, index, limit, count; |
| 296 | |
| 297 | if (sym == 0) |
| 298 | return 0; |
| 299 | |
| 300 | assert(0 < sym && sym <= n); |
| 301 | |
| 302 | count = table[0]; /* start with the whole table size */ |
| 303 | |
| 304 | bit = 1; |
| 305 | while (bit < n) |
| 306 | bit <<= 1; |
| 307 | |
| 308 | limit = n; |
| 309 | |
| 310 | while (bit > 0) { |
| 311 | /* |
| 312 | * Find the least number with its lowest set bit in this |
| 313 | * position which is greater than or equal to sym. |
| 314 | */ |
| 315 | index = ((sym + bit - 1) &~ (bit * 2 - 1)) + bit; |
| 316 | |
| 317 | if (index < limit) { |
| 318 | count -= table[index]; |
| 319 | limit = index; |
| 320 | } |
| 321 | |
| 322 | bit >>= 1; |
| 323 | } |
| 324 | |
| 325 | return count; |
| 326 | } |
| 327 | |
| 328 | /* |
| 329 | * Single frequency lookup: return the count of symbol `sym'. |
| 330 | */ |
| 331 | static int cf_slookup(int *table, int n, int sym) |
| 332 | { |
| 333 | int count, bit; |
| 334 | |
| 335 | assert(0 <= sym && sym < n); |
| 336 | |
| 337 | count = table[sym]; |
| 338 | |
| 339 | for (bit = 1; sym+bit < n && !(sym & bit); bit <<= 1) |
| 340 | count -= table[sym+bit]; |
| 341 | |
| 342 | return count; |
| 343 | } |
| 344 | |
| 345 | /* |
| 346 | * Return the largest symbol index such that the cumulative |
| 347 | * frequency up to that symbol is less than _or equal to_ count. |
| 348 | */ |
| 349 | static int cf_whichsym(int *table, int n, int count) { |
| 350 | int bit, sym, top; |
| 351 | |
| 352 | assert(count >= 0 && count < table[0]); |
| 353 | |
| 354 | bit = 1; |
| 355 | while (bit < n) |
| 356 | bit <<= 1; |
| 357 | |
| 358 | sym = 0; |
| 359 | top = table[0]; |
| 360 | |
| 361 | while (bit > 0) { |
| 362 | if (sym+bit < n) { |
| 363 | if (count >= top - table[sym+bit]) |
| 364 | sym += bit; |
| 365 | else |
| 366 | top -= table[sym+bit]; |
| 367 | } |
| 368 | |
| 369 | bit >>= 1; |
| 370 | } |
| 371 | |
| 372 | return sym; |
| 373 | } |
| 374 | |
| 375 | /* ---------------------------------------------------------------------- |
| 376 | * Map generation. |
| 377 | * |
| 378 | * FIXME: this isn't entirely optimal at present, because it |
| 379 | * inherently prioritises growing the largest region since there |
| 380 | * are more squares adjacent to it. This acts as a destabilising |
| 381 | * influence leading to a few large regions and mostly small ones. |
| 382 | * It might be better to do it some other way. |
| 383 | */ |
| 384 | |
| 385 | #define WEIGHT_INCREASED 2 /* for increased perimeter */ |
| 386 | #define WEIGHT_DECREASED 4 /* for decreased perimeter */ |
| 387 | #define WEIGHT_UNCHANGED 3 /* for unchanged perimeter */ |
| 388 | |
| 389 | /* |
| 390 | * Look at a square and decide which colours can be extended into |
| 391 | * it. |
| 392 | * |
| 393 | * If called with index < 0, it adds together one of |
| 394 | * WEIGHT_INCREASED, WEIGHT_DECREASED or WEIGHT_UNCHANGED for each |
| 395 | * colour that has a valid extension (according to the effect that |
| 396 | * it would have on the perimeter of the region being extended) and |
| 397 | * returns the overall total. |
| 398 | * |
| 399 | * If called with index >= 0, it returns one of the possible |
| 400 | * colours depending on the value of index, in such a way that the |
| 401 | * number of possible inputs which would give rise to a given |
| 402 | * return value correspond to the weight of that value. |
| 403 | */ |
| 404 | static int extend_options(int w, int h, int n, int *map, |
| 405 | int x, int y, int index) |
| 406 | { |
| 407 | int c, i, dx, dy; |
| 408 | int col[8]; |
| 409 | int total = 0; |
| 410 | |
| 411 | if (map[y*w+x] >= 0) { |
| 412 | assert(index < 0); |
| 413 | return 0; /* can't do this square at all */ |
| 414 | } |
| 415 | |
| 416 | /* |
| 417 | * Fetch the eight neighbours of this square, in order around |
| 418 | * the square. |
| 419 | */ |
| 420 | for (dy = -1; dy <= +1; dy++) |
| 421 | for (dx = -1; dx <= +1; dx++) { |
| 422 | int index = (dy < 0 ? 6-dx : dy > 0 ? 2+dx : 2*(1+dx)); |
| 423 | if (x+dx >= 0 && x+dx < w && y+dy >= 0 && y+dy < h) |
| 424 | col[index] = map[(y+dy)*w+(x+dx)]; |
| 425 | else |
| 426 | col[index] = -1; |
| 427 | } |
| 428 | |
| 429 | /* |
| 430 | * Iterate over each colour that might be feasible. |
| 431 | * |
| 432 | * FIXME: this routine currently has O(n) running time. We |
| 433 | * could turn it into O(FOUR) by only bothering to iterate over |
| 434 | * the colours mentioned in the four neighbouring squares. |
| 435 | */ |
| 436 | |
| 437 | for (c = 0; c < n; c++) { |
| 438 | int count, neighbours, runs; |
| 439 | |
| 440 | /* |
| 441 | * One of the even indices of col (representing the |
| 442 | * orthogonal neighbours of this square) must be equal to |
| 443 | * c, or else this square is not adjacent to region c and |
| 444 | * obviously cannot become an extension of it at this time. |
| 445 | */ |
| 446 | neighbours = 0; |
| 447 | for (i = 0; i < 8; i += 2) |
| 448 | if (col[i] == c) |
| 449 | neighbours++; |
| 450 | if (!neighbours) |
| 451 | continue; |
| 452 | |
| 453 | /* |
| 454 | * Now we know this square is adjacent to region c. The |
| 455 | * next question is, would extending it cause the region to |
| 456 | * become non-simply-connected? If so, we mustn't do it. |
| 457 | * |
| 458 | * We determine this by looking around col to see if we can |
| 459 | * find more than one separate run of colour c. |
| 460 | */ |
| 461 | runs = 0; |
| 462 | for (i = 0; i < 8; i++) |
| 463 | if (col[i] == c && col[(i+1) & 7] != c) |
| 464 | runs++; |
| 465 | if (runs > 1) |
| 466 | continue; |
| 467 | |
| 468 | assert(runs == 1); |
| 469 | |
| 470 | /* |
| 471 | * This square is a possibility. Determine its effect on |
| 472 | * the region's perimeter (computed from the number of |
| 473 | * orthogonal neighbours - 1 means a perimeter increase, 3 |
| 474 | * a decrease, 2 no change; 4 is impossible because the |
| 475 | * region would already not be simply connected) and we're |
| 476 | * done. |
| 477 | */ |
| 478 | assert(neighbours > 0 && neighbours < 4); |
| 479 | count = (neighbours == 1 ? WEIGHT_INCREASED : |
| 480 | neighbours == 2 ? WEIGHT_UNCHANGED : WEIGHT_DECREASED); |
| 481 | |
| 482 | total += count; |
| 483 | if (index >= 0 && index < count) |
| 484 | return c; |
| 485 | else |
| 486 | index -= count; |
| 487 | } |
| 488 | |
| 489 | assert(index < 0); |
| 490 | |
| 491 | return total; |
| 492 | } |
| 493 | |
| 494 | static void genmap(int w, int h, int n, int *map, random_state *rs) |
| 495 | { |
| 496 | int wh = w*h; |
| 497 | int x, y, i, k; |
| 498 | int *tmp; |
| 499 | |
| 500 | assert(n <= wh); |
| 501 | tmp = snewn(wh, int); |
| 502 | |
| 503 | /* |
| 504 | * Clear the map, and set up `tmp' as a list of grid indices. |
| 505 | */ |
| 506 | for (i = 0; i < wh; i++) { |
| 507 | map[i] = -1; |
| 508 | tmp[i] = i; |
| 509 | } |
| 510 | |
| 511 | /* |
| 512 | * Place the region seeds by selecting n members from `tmp'. |
| 513 | */ |
| 514 | k = wh; |
| 515 | for (i = 0; i < n; i++) { |
| 516 | int j = random_upto(rs, k); |
| 517 | map[tmp[j]] = i; |
| 518 | tmp[j] = tmp[--k]; |
| 519 | } |
| 520 | |
| 521 | /* |
| 522 | * Re-initialise `tmp' as a cumulative frequency table. This |
| 523 | * will store the number of possible region colours we can |
| 524 | * extend into each square. |
| 525 | */ |
| 526 | cf_init(tmp, wh); |
| 527 | |
| 528 | /* |
| 529 | * Go through the grid and set up the initial cumulative |
| 530 | * frequencies. |
| 531 | */ |
| 532 | for (y = 0; y < h; y++) |
| 533 | for (x = 0; x < w; x++) |
| 534 | cf_add(tmp, wh, y*w+x, |
| 535 | extend_options(w, h, n, map, x, y, -1)); |
| 536 | |
| 537 | /* |
| 538 | * Now repeatedly choose a square we can extend a region into, |
| 539 | * and do so. |
| 540 | */ |
| 541 | while (tmp[0] > 0) { |
| 542 | int k = random_upto(rs, tmp[0]); |
| 543 | int sq; |
| 544 | int colour; |
| 545 | int xx, yy; |
| 546 | |
| 547 | sq = cf_whichsym(tmp, wh, k); |
| 548 | k -= cf_clookup(tmp, wh, sq); |
| 549 | x = sq % w; |
| 550 | y = sq / w; |
| 551 | colour = extend_options(w, h, n, map, x, y, k); |
| 552 | |
| 553 | map[sq] = colour; |
| 554 | |
| 555 | /* |
| 556 | * Re-scan the nine cells around the one we've just |
| 557 | * modified. |
| 558 | */ |
| 559 | for (yy = max(y-1, 0); yy < min(y+2, h); yy++) |
| 560 | for (xx = max(x-1, 0); xx < min(x+2, w); xx++) { |
| 561 | cf_add(tmp, wh, yy*w+xx, |
| 562 | -cf_slookup(tmp, wh, yy*w+xx) + |
| 563 | extend_options(w, h, n, map, xx, yy, -1)); |
| 564 | } |
| 565 | } |
| 566 | |
| 567 | /* |
| 568 | * Finally, go through and normalise the region labels into |
| 569 | * order, meaning that indistinguishable maps are actually |
| 570 | * identical. |
| 571 | */ |
| 572 | for (i = 0; i < n; i++) |
| 573 | tmp[i] = -1; |
| 574 | k = 0; |
| 575 | for (i = 0; i < wh; i++) { |
| 576 | assert(map[i] >= 0); |
| 577 | if (tmp[map[i]] < 0) |
| 578 | tmp[map[i]] = k++; |
| 579 | map[i] = tmp[map[i]]; |
| 580 | } |
| 581 | |
| 582 | sfree(tmp); |
| 583 | } |
| 584 | |
| 585 | /* ---------------------------------------------------------------------- |
| 586 | * Functions to handle graphs. |
| 587 | */ |
| 588 | |
| 589 | /* |
| 590 | * Having got a map in a square grid, convert it into a graph |
| 591 | * representation. |
| 592 | */ |
| 593 | static int gengraph(int w, int h, int n, int *map, int *graph) |
| 594 | { |
| 595 | int i, j, x, y; |
| 596 | |
| 597 | /* |
| 598 | * Start by setting the graph up as an adjacency matrix. We'll |
| 599 | * turn it into a list later. |
| 600 | */ |
| 601 | for (i = 0; i < n*n; i++) |
| 602 | graph[i] = 0; |
| 603 | |
| 604 | /* |
| 605 | * Iterate over the map looking for all adjacencies. |
| 606 | */ |
| 607 | for (y = 0; y < h; y++) |
| 608 | for (x = 0; x < w; x++) { |
| 609 | int v, vx, vy; |
| 610 | v = map[y*w+x]; |
| 611 | if (x+1 < w && (vx = map[y*w+(x+1)]) != v) |
| 612 | graph[v*n+vx] = graph[vx*n+v] = 1; |
| 613 | if (y+1 < h && (vy = map[(y+1)*w+x]) != v) |
| 614 | graph[v*n+vy] = graph[vy*n+v] = 1; |
| 615 | } |
| 616 | |
| 617 | /* |
| 618 | * Turn the matrix into a list. |
| 619 | */ |
| 620 | for (i = j = 0; i < n*n; i++) |
| 621 | if (graph[i]) |
| 622 | graph[j++] = i; |
| 623 | |
| 624 | return j; |
| 625 | } |
| 626 | |
| 627 | static int graph_edge_index(int *graph, int n, int ngraph, int i, int j) |
| 628 | { |
| 629 | int v = i*n+j; |
| 630 | int top, bot, mid; |
| 631 | |
| 632 | bot = -1; |
| 633 | top = ngraph; |
| 634 | while (top - bot > 1) { |
| 635 | mid = (top + bot) / 2; |
| 636 | if (graph[mid] == v) |
| 637 | return mid; |
| 638 | else if (graph[mid] < v) |
| 639 | bot = mid; |
| 640 | else |
| 641 | top = mid; |
| 642 | } |
| 643 | return -1; |
| 644 | } |
| 645 | |
| 646 | #define graph_adjacent(graph, n, ngraph, i, j) \ |
| 647 | (graph_edge_index((graph), (n), (ngraph), (i), (j)) >= 0) |
| 648 | |
| 649 | static int graph_vertex_start(int *graph, int n, int ngraph, int i) |
| 650 | { |
| 651 | int v = i*n; |
| 652 | int top, bot, mid; |
| 653 | |
| 654 | bot = -1; |
| 655 | top = ngraph; |
| 656 | while (top - bot > 1) { |
| 657 | mid = (top + bot) / 2; |
| 658 | if (graph[mid] < v) |
| 659 | bot = mid; |
| 660 | else |
| 661 | top = mid; |
| 662 | } |
| 663 | return top; |
| 664 | } |
| 665 | |
| 666 | /* ---------------------------------------------------------------------- |
| 667 | * Generate a four-colouring of a graph. |
| 668 | * |
| 669 | * FIXME: it would be nice if we could convert this recursion into |
| 670 | * pseudo-recursion using some sort of explicit stack array, for |
| 671 | * the sake of the Palm port and its limited stack. |
| 672 | */ |
| 673 | |
| 674 | static int fourcolour_recurse(int *graph, int n, int ngraph, |
| 675 | int *colouring, int *scratch, random_state *rs) |
| 676 | { |
| 677 | int nfree, nvert, start, i, j, k, c, ci; |
| 678 | int cs[FOUR]; |
| 679 | |
| 680 | /* |
| 681 | * Find the smallest number of free colours in any uncoloured |
| 682 | * vertex, and count the number of such vertices. |
| 683 | */ |
| 684 | |
| 685 | nfree = FIVE; /* start off bigger than FOUR! */ |
| 686 | nvert = 0; |
| 687 | for (i = 0; i < n; i++) |
| 688 | if (colouring[i] < 0 && scratch[i*FIVE+FOUR] <= nfree) { |
| 689 | if (nfree > scratch[i*FIVE+FOUR]) { |
| 690 | nfree = scratch[i*FIVE+FOUR]; |
| 691 | nvert = 0; |
| 692 | } |
| 693 | nvert++; |
| 694 | } |
| 695 | |
| 696 | /* |
| 697 | * If there aren't any uncoloured vertices at all, we're done. |
| 698 | */ |
| 699 | if (nvert == 0) |
| 700 | return TRUE; /* we've got a colouring! */ |
| 701 | |
| 702 | /* |
| 703 | * Pick a random vertex in that set. |
| 704 | */ |
| 705 | j = random_upto(rs, nvert); |
| 706 | for (i = 0; i < n; i++) |
| 707 | if (colouring[i] < 0 && scratch[i*FIVE+FOUR] == nfree) |
| 708 | if (j-- == 0) |
| 709 | break; |
| 710 | assert(i < n); |
| 711 | start = graph_vertex_start(graph, n, ngraph, i); |
| 712 | |
| 713 | /* |
| 714 | * Loop over the possible colours for i, and recurse for each |
| 715 | * one. |
| 716 | */ |
| 717 | ci = 0; |
| 718 | for (c = 0; c < FOUR; c++) |
| 719 | if (scratch[i*FIVE+c] == 0) |
| 720 | cs[ci++] = c; |
| 721 | shuffle(cs, ci, sizeof(*cs), rs); |
| 722 | |
| 723 | while (ci-- > 0) { |
| 724 | c = cs[ci]; |
| 725 | |
| 726 | /* |
| 727 | * Fill in this colour. |
| 728 | */ |
| 729 | colouring[i] = c; |
| 730 | |
| 731 | /* |
| 732 | * Update the scratch space to reflect a new neighbour |
| 733 | * of this colour for each neighbour of vertex i. |
| 734 | */ |
| 735 | for (j = start; j < ngraph && graph[j] < n*(i+1); j++) { |
| 736 | k = graph[j] - i*n; |
| 737 | if (scratch[k*FIVE+c] == 0) |
| 738 | scratch[k*FIVE+FOUR]--; |
| 739 | scratch[k*FIVE+c]++; |
| 740 | } |
| 741 | |
| 742 | /* |
| 743 | * Recurse. |
| 744 | */ |
| 745 | if (fourcolour_recurse(graph, n, ngraph, colouring, scratch, rs)) |
| 746 | return TRUE; /* got one! */ |
| 747 | |
| 748 | /* |
| 749 | * If that didn't work, clean up and try again with a |
| 750 | * different colour. |
| 751 | */ |
| 752 | for (j = start; j < ngraph && graph[j] < n*(i+1); j++) { |
| 753 | k = graph[j] - i*n; |
| 754 | scratch[k*FIVE+c]--; |
| 755 | if (scratch[k*FIVE+c] == 0) |
| 756 | scratch[k*FIVE+FOUR]++; |
| 757 | } |
| 758 | colouring[i] = -1; |
| 759 | } |
| 760 | |
| 761 | /* |
| 762 | * If we reach here, we were unable to find a colouring at all. |
| 763 | * (This doesn't necessarily mean the Four Colour Theorem is |
| 764 | * violated; it might just mean we've gone down a dead end and |
| 765 | * need to back up and look somewhere else. It's only an FCT |
| 766 | * violation if we get all the way back up to the top level and |
| 767 | * still fail.) |
| 768 | */ |
| 769 | return FALSE; |
| 770 | } |
| 771 | |
| 772 | static void fourcolour(int *graph, int n, int ngraph, int *colouring, |
| 773 | random_state *rs) |
| 774 | { |
| 775 | int *scratch; |
| 776 | int i; |
| 777 | |
| 778 | /* |
| 779 | * For each vertex and each colour, we store the number of |
| 780 | * neighbours that have that colour. Also, we store the number |
| 781 | * of free colours for the vertex. |
| 782 | */ |
| 783 | scratch = snewn(n * FIVE, int); |
| 784 | for (i = 0; i < n * FIVE; i++) |
| 785 | scratch[i] = (i % FIVE == FOUR ? FOUR : 0); |
| 786 | |
| 787 | /* |
| 788 | * Clear the colouring to start with. |
| 789 | */ |
| 790 | for (i = 0; i < n; i++) |
| 791 | colouring[i] = -1; |
| 792 | |
| 793 | i = fourcolour_recurse(graph, n, ngraph, colouring, scratch, rs); |
| 794 | assert(i); /* by the Four Colour Theorem :-) */ |
| 795 | |
| 796 | sfree(scratch); |
| 797 | } |
| 798 | |
| 799 | /* ---------------------------------------------------------------------- |
| 800 | * Non-recursive solver. |
| 801 | */ |
| 802 | |
| 803 | struct solver_scratch { |
| 804 | unsigned char *possible; /* bitmap of colours for each region */ |
| 805 | |
| 806 | int *graph; |
| 807 | int n; |
| 808 | int ngraph; |
| 809 | |
| 810 | int *bfsqueue; |
| 811 | int *bfscolour; |
| 812 | #ifdef SOLVER_DIAGNOSTICS |
| 813 | int *bfsprev; |
| 814 | #endif |
| 815 | |
| 816 | int depth; |
| 817 | }; |
| 818 | |
| 819 | static struct solver_scratch *new_scratch(int *graph, int n, int ngraph) |
| 820 | { |
| 821 | struct solver_scratch *sc; |
| 822 | |
| 823 | sc = snew(struct solver_scratch); |
| 824 | sc->graph = graph; |
| 825 | sc->n = n; |
| 826 | sc->ngraph = ngraph; |
| 827 | sc->possible = snewn(n, unsigned char); |
| 828 | sc->depth = 0; |
| 829 | sc->bfsqueue = snewn(n, int); |
| 830 | sc->bfscolour = snewn(n, int); |
| 831 | #ifdef SOLVER_DIAGNOSTICS |
| 832 | sc->bfsprev = snewn(n, int); |
| 833 | #endif |
| 834 | |
| 835 | return sc; |
| 836 | } |
| 837 | |
| 838 | static void free_scratch(struct solver_scratch *sc) |
| 839 | { |
| 840 | sfree(sc->possible); |
| 841 | sfree(sc->bfsqueue); |
| 842 | sfree(sc->bfscolour); |
| 843 | #ifdef SOLVER_DIAGNOSTICS |
| 844 | sfree(sc->bfsprev); |
| 845 | #endif |
| 846 | sfree(sc); |
| 847 | } |
| 848 | |
| 849 | /* |
| 850 | * Count the bits in a word. Only needs to cope with FOUR bits. |
| 851 | */ |
| 852 | static int bitcount(int word) |
| 853 | { |
| 854 | assert(FOUR <= 4); /* or this needs changing */ |
| 855 | word = ((word & 0xA) >> 1) + (word & 0x5); |
| 856 | word = ((word & 0xC) >> 2) + (word & 0x3); |
| 857 | return word; |
| 858 | } |
| 859 | |
| 860 | #ifdef SOLVER_DIAGNOSTICS |
| 861 | static const char colnames[FOUR] = { 'R', 'Y', 'G', 'B' }; |
| 862 | #endif |
| 863 | |
| 864 | static int place_colour(struct solver_scratch *sc, |
| 865 | int *colouring, int index, int colour |
| 866 | #ifdef SOLVER_DIAGNOSTICS |
| 867 | , char *verb |
| 868 | #endif |
| 869 | ) |
| 870 | { |
| 871 | int *graph = sc->graph, n = sc->n, ngraph = sc->ngraph; |
| 872 | int j, k; |
| 873 | |
| 874 | if (!(sc->possible[index] & (1 << colour))) { |
| 875 | #ifdef SOLVER_DIAGNOSTICS |
| 876 | if (verbose) |
| 877 | printf("%*scannot place %c in region %d\n", 2*sc->depth, "", |
| 878 | colnames[colour], index); |
| 879 | #endif |
| 880 | return FALSE; /* can't do it */ |
| 881 | } |
| 882 | |
| 883 | sc->possible[index] = 1 << colour; |
| 884 | colouring[index] = colour; |
| 885 | |
| 886 | #ifdef SOLVER_DIAGNOSTICS |
| 887 | if (verbose) |
| 888 | printf("%*s%s %c in region %d\n", 2*sc->depth, "", |
| 889 | verb, colnames[colour], index); |
| 890 | #endif |
| 891 | |
| 892 | /* |
| 893 | * Rule out this colour from all the region's neighbours. |
| 894 | */ |
| 895 | for (j = graph_vertex_start(graph, n, ngraph, index); |
| 896 | j < ngraph && graph[j] < n*(index+1); j++) { |
| 897 | k = graph[j] - index*n; |
| 898 | #ifdef SOLVER_DIAGNOSTICS |
| 899 | if (verbose && (sc->possible[k] & (1 << colour))) |
| 900 | printf("%*s ruling out %c in region %d\n", 2*sc->depth, "", |
| 901 | colnames[colour], k); |
| 902 | #endif |
| 903 | sc->possible[k] &= ~(1 << colour); |
| 904 | } |
| 905 | |
| 906 | return TRUE; |
| 907 | } |
| 908 | |
| 909 | #ifdef SOLVER_DIAGNOSTICS |
| 910 | static char *colourset(char *buf, int set) |
| 911 | { |
| 912 | int i; |
| 913 | char *p = buf; |
| 914 | char *sep = ""; |
| 915 | |
| 916 | for (i = 0; i < FOUR; i++) |
| 917 | if (set & (1 << i)) { |
| 918 | p += sprintf(p, "%s%c", sep, colnames[i]); |
| 919 | sep = ","; |
| 920 | } |
| 921 | |
| 922 | return buf; |
| 923 | } |
| 924 | #endif |
| 925 | |
| 926 | /* |
| 927 | * Returns 0 for impossible, 1 for success, 2 for failure to |
| 928 | * converge (i.e. puzzle is either ambiguous or just too |
| 929 | * difficult). |
| 930 | */ |
| 931 | static int map_solver(struct solver_scratch *sc, |
| 932 | int *graph, int n, int ngraph, int *colouring, |
| 933 | int difficulty) |
| 934 | { |
| 935 | int i; |
| 936 | |
| 937 | if (sc->depth == 0) { |
| 938 | /* |
| 939 | * Initialise scratch space. |
| 940 | */ |
| 941 | for (i = 0; i < n; i++) |
| 942 | sc->possible[i] = (1 << FOUR) - 1; |
| 943 | |
| 944 | /* |
| 945 | * Place clues. |
| 946 | */ |
| 947 | for (i = 0; i < n; i++) |
| 948 | if (colouring[i] >= 0) { |
| 949 | if (!place_colour(sc, colouring, i, colouring[i] |
| 950 | #ifdef SOLVER_DIAGNOSTICS |
| 951 | , "initial clue:" |
| 952 | #endif |
| 953 | )) { |
| 954 | #ifdef SOLVER_DIAGNOSTICS |
| 955 | if (verbose) |
| 956 | printf("%*sinitial clue set is inconsistent\n", |
| 957 | 2*sc->depth, ""); |
| 958 | #endif |
| 959 | return 0; /* the clues aren't even consistent! */ |
| 960 | } |
| 961 | } |
| 962 | } |
| 963 | |
| 964 | /* |
| 965 | * Now repeatedly loop until we find nothing further to do. |
| 966 | */ |
| 967 | while (1) { |
| 968 | int done_something = FALSE; |
| 969 | |
| 970 | if (difficulty < DIFF_EASY) |
| 971 | break; /* can't do anything at all! */ |
| 972 | |
| 973 | /* |
| 974 | * Simplest possible deduction: find a region with only one |
| 975 | * possible colour. |
| 976 | */ |
| 977 | for (i = 0; i < n; i++) if (colouring[i] < 0) { |
| 978 | int p = sc->possible[i]; |
| 979 | |
| 980 | if (p == 0) { |
| 981 | #ifdef SOLVER_DIAGNOSTICS |
| 982 | if (verbose) |
| 983 | printf("%*sregion %d has no possible colours left\n", |
| 984 | 2*sc->depth, "", i); |
| 985 | #endif |
| 986 | return 0; /* puzzle is inconsistent */ |
| 987 | } |
| 988 | |
| 989 | if ((p & (p-1)) == 0) { /* p is a power of two */ |
| 990 | int c, ret; |
| 991 | for (c = 0; c < FOUR; c++) |
| 992 | if (p == (1 << c)) |
| 993 | break; |
| 994 | assert(c < FOUR); |
| 995 | ret = place_colour(sc, colouring, i, c |
| 996 | #ifdef SOLVER_DIAGNOSTICS |
| 997 | , "placing" |
| 998 | #endif |
| 999 | ); |
| 1000 | /* |
| 1001 | * place_colour() can only fail if colour c was not |
| 1002 | * even a _possibility_ for region i, and we're |
| 1003 | * pretty sure it was because we checked before |
| 1004 | * calling place_colour(). So we can safely assert |
| 1005 | * here rather than having to return a nice |
| 1006 | * friendly error code. |
| 1007 | */ |
| 1008 | assert(ret); |
| 1009 | done_something = TRUE; |
| 1010 | } |
| 1011 | } |
| 1012 | |
| 1013 | if (done_something) |
| 1014 | continue; |
| 1015 | |
| 1016 | if (difficulty < DIFF_NORMAL) |
| 1017 | break; /* can't do anything harder */ |
| 1018 | |
| 1019 | /* |
| 1020 | * Failing that, go up one level. Look for pairs of regions |
| 1021 | * which (a) both have the same pair of possible colours, |
| 1022 | * (b) are adjacent to one another, (c) are adjacent to the |
| 1023 | * same region, and (d) that region still thinks it has one |
| 1024 | * or both of those possible colours. |
| 1025 | * |
| 1026 | * Simplest way to do this is by going through the graph |
| 1027 | * edge by edge, so that we start with property (b) and |
| 1028 | * then look for (a) and finally (c) and (d). |
| 1029 | */ |
| 1030 | for (i = 0; i < ngraph; i++) { |
| 1031 | int j1 = graph[i] / n, j2 = graph[i] % n; |
| 1032 | int j, k, v, v2; |
| 1033 | #ifdef SOLVER_DIAGNOSTICS |
| 1034 | int started = FALSE; |
| 1035 | #endif |
| 1036 | |
| 1037 | if (j1 > j2) |
| 1038 | continue; /* done it already, other way round */ |
| 1039 | |
| 1040 | if (colouring[j1] >= 0 || colouring[j2] >= 0) |
| 1041 | continue; /* they're not undecided */ |
| 1042 | |
| 1043 | if (sc->possible[j1] != sc->possible[j2]) |
| 1044 | continue; /* they don't have the same possibles */ |
| 1045 | |
| 1046 | v = sc->possible[j1]; |
| 1047 | /* |
| 1048 | * See if v contains exactly two set bits. |
| 1049 | */ |
| 1050 | v2 = v & -v; /* find lowest set bit */ |
| 1051 | v2 = v & ~v2; /* clear it */ |
| 1052 | if (v2 == 0 || (v2 & (v2-1)) != 0) /* not power of 2 */ |
| 1053 | continue; |
| 1054 | |
| 1055 | /* |
| 1056 | * We've found regions j1 and j2 satisfying properties |
| 1057 | * (a) and (b): they have two possible colours between |
| 1058 | * them, and since they're adjacent to one another they |
| 1059 | * must use _both_ those colours between them. |
| 1060 | * Therefore, if they are both adjacent to any other |
| 1061 | * region then that region cannot be either colour. |
| 1062 | * |
| 1063 | * Go through the neighbours of j1 and see if any are |
| 1064 | * shared with j2. |
| 1065 | */ |
| 1066 | for (j = graph_vertex_start(graph, n, ngraph, j1); |
| 1067 | j < ngraph && graph[j] < n*(j1+1); j++) { |
| 1068 | k = graph[j] - j1*n; |
| 1069 | if (graph_adjacent(graph, n, ngraph, k, j2) && |
| 1070 | (sc->possible[k] & v)) { |
| 1071 | #ifdef SOLVER_DIAGNOSTICS |
| 1072 | if (verbose) { |
| 1073 | char buf[80]; |
| 1074 | if (!started) |
| 1075 | printf("%*sadjacent regions %d,%d share colours" |
| 1076 | " %s\n", 2*sc->depth, "", j1, j2, |
| 1077 | colourset(buf, v)); |
| 1078 | started = TRUE; |
| 1079 | printf("%*s ruling out %s in region %d\n",2*sc->depth, |
| 1080 | "", colourset(buf, sc->possible[k] & v), k); |
| 1081 | } |
| 1082 | #endif |
| 1083 | sc->possible[k] &= ~v; |
| 1084 | done_something = TRUE; |
| 1085 | } |
| 1086 | } |
| 1087 | } |
| 1088 | |
| 1089 | if (done_something) |
| 1090 | continue; |
| 1091 | |
| 1092 | if (difficulty < DIFF_HARD) |
| 1093 | break; /* can't do anything harder */ |
| 1094 | |
| 1095 | /* |
| 1096 | * Right; now we get creative. Now we're going to look for |
| 1097 | * `forcing chains'. A forcing chain is a path through the |
| 1098 | * graph with the following properties: |
| 1099 | * |
| 1100 | * (a) Each vertex on the path has precisely two possible |
| 1101 | * colours. |
| 1102 | * |
| 1103 | * (b) Each pair of vertices which are adjacent on the |
| 1104 | * path share at least one possible colour in common. |
| 1105 | * |
| 1106 | * (c) Each vertex in the middle of the path shares _both_ |
| 1107 | * of its colours with at least one of its neighbours |
| 1108 | * (not the same one with both neighbours). |
| 1109 | * |
| 1110 | * These together imply that at least one of the possible |
| 1111 | * colour choices at one end of the path forces _all_ the |
| 1112 | * rest of the colours along the path. In order to make |
| 1113 | * real use of this, we need further properties: |
| 1114 | * |
| 1115 | * (c) Ruling out some colour C from the vertex at one end |
| 1116 | * of the path forces the vertex at the other end to |
| 1117 | * take colour C. |
| 1118 | * |
| 1119 | * (d) The two end vertices are mutually adjacent to some |
| 1120 | * third vertex. |
| 1121 | * |
| 1122 | * (e) That third vertex currently has C as a possibility. |
| 1123 | * |
| 1124 | * If we can find all of that lot, we can deduce that at |
| 1125 | * least one of the two ends of the forcing chain has |
| 1126 | * colour C, and that therefore the mutually adjacent third |
| 1127 | * vertex does not. |
| 1128 | * |
| 1129 | * To find forcing chains, we're going to start a bfs at |
| 1130 | * each suitable vertex of the graph, once for each of its |
| 1131 | * two possible colours. |
| 1132 | */ |
| 1133 | for (i = 0; i < n; i++) { |
| 1134 | int c; |
| 1135 | |
| 1136 | if (colouring[i] >= 0 || bitcount(sc->possible[i]) != 2) |
| 1137 | continue; |
| 1138 | |
| 1139 | for (c = 0; c < FOUR; c++) |
| 1140 | if (sc->possible[i] & (1 << c)) { |
| 1141 | int j, k, gi, origc, currc, head, tail; |
| 1142 | /* |
| 1143 | * Try a bfs from this vertex, ruling out |
| 1144 | * colour c. |
| 1145 | * |
| 1146 | * Within this loop, we work in colour bitmaps |
| 1147 | * rather than actual colours, because |
| 1148 | * converting back and forth is a needless |
| 1149 | * computational expense. |
| 1150 | */ |
| 1151 | |
| 1152 | origc = 1 << c; |
| 1153 | |
| 1154 | for (j = 0; j < n; j++) { |
| 1155 | sc->bfscolour[j] = -1; |
| 1156 | #ifdef SOLVER_DIAGNOSTICS |
| 1157 | sc->bfsprev[j] = -1; |
| 1158 | #endif |
| 1159 | } |
| 1160 | head = tail = 0; |
| 1161 | sc->bfsqueue[tail++] = i; |
| 1162 | sc->bfscolour[i] = sc->possible[i] &~ origc; |
| 1163 | |
| 1164 | while (head < tail) { |
| 1165 | j = sc->bfsqueue[head++]; |
| 1166 | currc = sc->bfscolour[j]; |
| 1167 | |
| 1168 | /* |
| 1169 | * Try neighbours of j. |
| 1170 | */ |
| 1171 | for (gi = graph_vertex_start(graph, n, ngraph, j); |
| 1172 | gi < ngraph && graph[gi] < n*(j+1); gi++) { |
| 1173 | k = graph[gi] - j*n; |
| 1174 | |
| 1175 | /* |
| 1176 | * To continue with the bfs in vertex |
| 1177 | * k, we need k to be |
| 1178 | * (a) not already visited |
| 1179 | * (b) have two possible colours |
| 1180 | * (c) those colours include currc. |
| 1181 | */ |
| 1182 | |
| 1183 | if (sc->bfscolour[k] < 0 && |
| 1184 | colouring[k] < 0 && |
| 1185 | bitcount(sc->possible[k]) == 2 && |
| 1186 | (sc->possible[k] & currc)) { |
| 1187 | sc->bfsqueue[tail++] = k; |
| 1188 | sc->bfscolour[k] = |
| 1189 | sc->possible[k] &~ currc; |
| 1190 | #ifdef SOLVER_DIAGNOSTICS |
| 1191 | sc->bfsprev[k] = j; |
| 1192 | #endif |
| 1193 | } |
| 1194 | |
| 1195 | /* |
| 1196 | * One other possibility is that k |
| 1197 | * might be the region in which we can |
| 1198 | * make a real deduction: if it's |
| 1199 | * adjacent to i, contains currc as a |
| 1200 | * possibility, and currc is equal to |
| 1201 | * the original colour we ruled out. |
| 1202 | */ |
| 1203 | if (currc == origc && |
| 1204 | graph_adjacent(graph, n, ngraph, k, i) && |
| 1205 | (sc->possible[k] & currc)) { |
| 1206 | #ifdef SOLVER_DIAGNOSTICS |
| 1207 | if (verbose) { |
| 1208 | char buf[80], *sep = ""; |
| 1209 | int r; |
| 1210 | |
| 1211 | printf("%*sforcing chain, colour %s, ", |
| 1212 | 2*sc->depth, "", |
| 1213 | colourset(buf, origc)); |
| 1214 | for (r = j; r != -1; r = sc->bfsprev[r]) { |
| 1215 | printf("%s%d", sep, r); |
| 1216 | sep = "-"; |
| 1217 | } |
| 1218 | printf("\n%*s ruling out %s in region" |
| 1219 | " %d\n", 2*sc->depth, "", |
| 1220 | colourset(buf, origc), k); |
| 1221 | } |
| 1222 | #endif |
| 1223 | sc->possible[k] &= ~origc; |
| 1224 | done_something = TRUE; |
| 1225 | } |
| 1226 | } |
| 1227 | } |
| 1228 | |
| 1229 | assert(tail <= n); |
| 1230 | } |
| 1231 | } |
| 1232 | |
| 1233 | if (!done_something) |
| 1234 | break; |
| 1235 | } |
| 1236 | |
| 1237 | /* |
| 1238 | * See if we've got a complete solution, and return if so. |
| 1239 | */ |
| 1240 | for (i = 0; i < n; i++) |
| 1241 | if (colouring[i] < 0) |
| 1242 | break; |
| 1243 | if (i == n) { |
| 1244 | #ifdef SOLVER_DIAGNOSTICS |
| 1245 | if (verbose) |
| 1246 | printf("%*sone solution found\n", 2*sc->depth, ""); |
| 1247 | #endif |
| 1248 | return 1; /* success! */ |
| 1249 | } |
| 1250 | |
| 1251 | /* |
| 1252 | * If recursion is not permissible, we now give up. |
| 1253 | */ |
| 1254 | if (difficulty < DIFF_RECURSE) { |
| 1255 | #ifdef SOLVER_DIAGNOSTICS |
| 1256 | if (verbose) |
| 1257 | printf("%*sunable to proceed further without recursion\n", |
| 1258 | 2*sc->depth, ""); |
| 1259 | #endif |
| 1260 | return 2; /* unable to complete */ |
| 1261 | } |
| 1262 | |
| 1263 | /* |
| 1264 | * Now we've got to do something recursive. So first hunt for a |
| 1265 | * currently-most-constrained region. |
| 1266 | */ |
| 1267 | { |
| 1268 | int best, bestc; |
| 1269 | struct solver_scratch *rsc; |
| 1270 | int *subcolouring, *origcolouring; |
| 1271 | int ret, subret; |
| 1272 | int we_already_got_one; |
| 1273 | |
| 1274 | best = -1; |
| 1275 | bestc = FIVE; |
| 1276 | |
| 1277 | for (i = 0; i < n; i++) if (colouring[i] < 0) { |
| 1278 | int p = sc->possible[i]; |
| 1279 | enum { compile_time_assertion = 1 / (FOUR <= 4) }; |
| 1280 | int c; |
| 1281 | |
| 1282 | /* Count the set bits. */ |
| 1283 | c = (p & 5) + ((p >> 1) & 5); |
| 1284 | c = (c & 3) + ((c >> 2) & 3); |
| 1285 | assert(c > 1); /* or colouring[i] would be >= 0 */ |
| 1286 | |
| 1287 | if (c < bestc) { |
| 1288 | best = i; |
| 1289 | bestc = c; |
| 1290 | } |
| 1291 | } |
| 1292 | |
| 1293 | assert(best >= 0); /* or we'd be solved already */ |
| 1294 | |
| 1295 | #ifdef SOLVER_DIAGNOSTICS |
| 1296 | if (verbose) |
| 1297 | printf("%*srecursing on region %d\n", 2*sc->depth, "", best); |
| 1298 | #endif |
| 1299 | |
| 1300 | /* |
| 1301 | * Now iterate over the possible colours for this region. |
| 1302 | */ |
| 1303 | rsc = new_scratch(graph, n, ngraph); |
| 1304 | rsc->depth = sc->depth + 1; |
| 1305 | origcolouring = snewn(n, int); |
| 1306 | memcpy(origcolouring, colouring, n * sizeof(int)); |
| 1307 | subcolouring = snewn(n, int); |
| 1308 | we_already_got_one = FALSE; |
| 1309 | ret = 0; |
| 1310 | |
| 1311 | for (i = 0; i < FOUR; i++) { |
| 1312 | if (!(sc->possible[best] & (1 << i))) |
| 1313 | continue; |
| 1314 | |
| 1315 | memcpy(rsc->possible, sc->possible, n); |
| 1316 | memcpy(subcolouring, origcolouring, n * sizeof(int)); |
| 1317 | |
| 1318 | place_colour(rsc, subcolouring, best, i |
| 1319 | #ifdef SOLVER_DIAGNOSTICS |
| 1320 | , "trying" |
| 1321 | #endif |
| 1322 | ); |
| 1323 | |
| 1324 | subret = map_solver(rsc, graph, n, ngraph, |
| 1325 | subcolouring, difficulty); |
| 1326 | |
| 1327 | #ifdef SOLVER_DIAGNOSTICS |
| 1328 | if (verbose) { |
| 1329 | printf("%*sretracting %c in region %d; found %s\n", |
| 1330 | 2*sc->depth, "", colnames[i], best, |
| 1331 | subret == 0 ? "no solutions" : |
| 1332 | subret == 1 ? "one solution" : "multiple solutions"); |
| 1333 | } |
| 1334 | #endif |
| 1335 | |
| 1336 | /* |
| 1337 | * If this possibility turned up more than one valid |
| 1338 | * solution, or if it turned up one and we already had |
| 1339 | * one, we're definitely ambiguous. |
| 1340 | */ |
| 1341 | if (subret == 2 || (subret == 1 && we_already_got_one)) { |
| 1342 | ret = 2; |
| 1343 | break; |
| 1344 | } |
| 1345 | |
| 1346 | /* |
| 1347 | * If this possibility turned up one valid solution and |
| 1348 | * it's the first we've seen, copy it into the output. |
| 1349 | */ |
| 1350 | if (subret == 1) { |
| 1351 | memcpy(colouring, subcolouring, n * sizeof(int)); |
| 1352 | we_already_got_one = TRUE; |
| 1353 | ret = 1; |
| 1354 | } |
| 1355 | |
| 1356 | /* |
| 1357 | * Otherwise, this guess led to a contradiction, so we |
| 1358 | * do nothing. |
| 1359 | */ |
| 1360 | } |
| 1361 | |
| 1362 | sfree(subcolouring); |
| 1363 | free_scratch(rsc); |
| 1364 | |
| 1365 | #ifdef SOLVER_DIAGNOSTICS |
| 1366 | if (verbose && sc->depth == 0) { |
| 1367 | printf("%*s%s found\n", |
| 1368 | 2*sc->depth, "", |
| 1369 | ret == 0 ? "no solutions" : |
| 1370 | ret == 1 ? "one solution" : "multiple solutions"); |
| 1371 | } |
| 1372 | #endif |
| 1373 | return ret; |
| 1374 | } |
| 1375 | } |
| 1376 | |
| 1377 | /* ---------------------------------------------------------------------- |
| 1378 | * Game generation main function. |
| 1379 | */ |
| 1380 | |
| 1381 | static char *new_game_desc(game_params *params, random_state *rs, |
| 1382 | char **aux, int interactive) |
| 1383 | { |
| 1384 | struct solver_scratch *sc = NULL; |
| 1385 | int *map, *graph, ngraph, *colouring, *colouring2, *regions; |
| 1386 | int i, j, w, h, n, solveret, cfreq[FOUR]; |
| 1387 | int wh; |
| 1388 | int mindiff, tries; |
| 1389 | #ifdef GENERATION_DIAGNOSTICS |
| 1390 | int x, y; |
| 1391 | #endif |
| 1392 | char *ret, buf[80]; |
| 1393 | int retlen, retsize; |
| 1394 | |
| 1395 | w = params->w; |
| 1396 | h = params->h; |
| 1397 | n = params->n; |
| 1398 | wh = w*h; |
| 1399 | |
| 1400 | *aux = NULL; |
| 1401 | |
| 1402 | map = snewn(wh, int); |
| 1403 | graph = snewn(n*n, int); |
| 1404 | colouring = snewn(n, int); |
| 1405 | colouring2 = snewn(n, int); |
| 1406 | regions = snewn(n, int); |
| 1407 | |
| 1408 | /* |
| 1409 | * This is the minimum difficulty below which we'll completely |
| 1410 | * reject a map design. Normally we set this to one below the |
| 1411 | * requested difficulty, ensuring that we have the right |
| 1412 | * result. However, for particularly dense maps or maps with |
| 1413 | * particularly few regions it might not be possible to get the |
| 1414 | * desired difficulty, so we will eventually drop this down to |
| 1415 | * -1 to indicate that any old map will do. |
| 1416 | */ |
| 1417 | mindiff = params->diff; |
| 1418 | tries = 50; |
| 1419 | |
| 1420 | while (1) { |
| 1421 | |
| 1422 | /* |
| 1423 | * Create the map. |
| 1424 | */ |
| 1425 | genmap(w, h, n, map, rs); |
| 1426 | |
| 1427 | #ifdef GENERATION_DIAGNOSTICS |
| 1428 | for (y = 0; y < h; y++) { |
| 1429 | for (x = 0; x < w; x++) { |
| 1430 | int v = map[y*w+x]; |
| 1431 | if (v >= 62) |
| 1432 | putchar('!'); |
| 1433 | else if (v >= 36) |
| 1434 | putchar('a' + v-36); |
| 1435 | else if (v >= 10) |
| 1436 | putchar('A' + v-10); |
| 1437 | else |
| 1438 | putchar('0' + v); |
| 1439 | } |
| 1440 | putchar('\n'); |
| 1441 | } |
| 1442 | #endif |
| 1443 | |
| 1444 | /* |
| 1445 | * Convert the map into a graph. |
| 1446 | */ |
| 1447 | ngraph = gengraph(w, h, n, map, graph); |
| 1448 | |
| 1449 | #ifdef GENERATION_DIAGNOSTICS |
| 1450 | for (i = 0; i < ngraph; i++) |
| 1451 | printf("%d-%d\n", graph[i]/n, graph[i]%n); |
| 1452 | #endif |
| 1453 | |
| 1454 | /* |
| 1455 | * Colour the map. |
| 1456 | */ |
| 1457 | fourcolour(graph, n, ngraph, colouring, rs); |
| 1458 | |
| 1459 | #ifdef GENERATION_DIAGNOSTICS |
| 1460 | for (i = 0; i < n; i++) |
| 1461 | printf("%d: %d\n", i, colouring[i]); |
| 1462 | |
| 1463 | for (y = 0; y < h; y++) { |
| 1464 | for (x = 0; x < w; x++) { |
| 1465 | int v = colouring[map[y*w+x]]; |
| 1466 | if (v >= 36) |
| 1467 | putchar('a' + v-36); |
| 1468 | else if (v >= 10) |
| 1469 | putchar('A' + v-10); |
| 1470 | else |
| 1471 | putchar('0' + v); |
| 1472 | } |
| 1473 | putchar('\n'); |
| 1474 | } |
| 1475 | #endif |
| 1476 | |
| 1477 | /* |
| 1478 | * Encode the solution as an aux string. |
| 1479 | */ |
| 1480 | if (*aux) /* in case we've come round again */ |
| 1481 | sfree(*aux); |
| 1482 | retlen = retsize = 0; |
| 1483 | ret = NULL; |
| 1484 | for (i = 0; i < n; i++) { |
| 1485 | int len; |
| 1486 | |
| 1487 | if (colouring[i] < 0) |
| 1488 | continue; |
| 1489 | |
| 1490 | len = sprintf(buf, "%s%d:%d", i ? ";" : "S;", colouring[i], i); |
| 1491 | if (retlen + len >= retsize) { |
| 1492 | retsize = retlen + len + 256; |
| 1493 | ret = sresize(ret, retsize, char); |
| 1494 | } |
| 1495 | strcpy(ret + retlen, buf); |
| 1496 | retlen += len; |
| 1497 | } |
| 1498 | *aux = ret; |
| 1499 | |
| 1500 | /* |
| 1501 | * Remove the region colours one by one, keeping |
| 1502 | * solubility. Also ensure that there always remains at |
| 1503 | * least one region of every colour, so that the user can |
| 1504 | * drag from somewhere. |
| 1505 | */ |
| 1506 | for (i = 0; i < FOUR; i++) |
| 1507 | cfreq[i] = 0; |
| 1508 | for (i = 0; i < n; i++) { |
| 1509 | regions[i] = i; |
| 1510 | cfreq[colouring[i]]++; |
| 1511 | } |
| 1512 | for (i = 0; i < FOUR; i++) |
| 1513 | if (cfreq[i] == 0) |
| 1514 | continue; |
| 1515 | |
| 1516 | shuffle(regions, n, sizeof(*regions), rs); |
| 1517 | |
| 1518 | if (sc) free_scratch(sc); |
| 1519 | sc = new_scratch(graph, n, ngraph); |
| 1520 | |
| 1521 | for (i = 0; i < n; i++) { |
| 1522 | j = regions[i]; |
| 1523 | |
| 1524 | if (cfreq[colouring[j]] == 1) |
| 1525 | continue; /* can't remove last region of colour */ |
| 1526 | |
| 1527 | memcpy(colouring2, colouring, n*sizeof(int)); |
| 1528 | colouring2[j] = -1; |
| 1529 | solveret = map_solver(sc, graph, n, ngraph, colouring2, |
| 1530 | params->diff); |
| 1531 | assert(solveret >= 0); /* mustn't be impossible! */ |
| 1532 | if (solveret == 1) { |
| 1533 | cfreq[colouring[j]]--; |
| 1534 | colouring[j] = -1; |
| 1535 | } |
| 1536 | } |
| 1537 | |
| 1538 | #ifdef GENERATION_DIAGNOSTICS |
| 1539 | for (i = 0; i < n; i++) |
| 1540 | if (colouring[i] >= 0) { |
| 1541 | if (i >= 62) |
| 1542 | putchar('!'); |
| 1543 | else if (i >= 36) |
| 1544 | putchar('a' + i-36); |
| 1545 | else if (i >= 10) |
| 1546 | putchar('A' + i-10); |
| 1547 | else |
| 1548 | putchar('0' + i); |
| 1549 | printf(": %d\n", colouring[i]); |
| 1550 | } |
| 1551 | #endif |
| 1552 | |
| 1553 | /* |
| 1554 | * Finally, check that the puzzle is _at least_ as hard as |
| 1555 | * required, and indeed that it isn't already solved. |
| 1556 | * (Calling map_solver with negative difficulty ensures the |
| 1557 | * latter - if a solver which _does nothing_ can solve it, |
| 1558 | * it's too easy!) |
| 1559 | */ |
| 1560 | memcpy(colouring2, colouring, n*sizeof(int)); |
| 1561 | if (map_solver(sc, graph, n, ngraph, colouring2, |
| 1562 | mindiff - 1) == 1) { |
| 1563 | /* |
| 1564 | * Drop minimum difficulty if necessary. |
| 1565 | */ |
| 1566 | if (mindiff > 0 && (n < 9 || n > 2*wh/3)) { |
| 1567 | if (tries-- <= 0) |
| 1568 | mindiff = 0; /* give up and go for Easy */ |
| 1569 | } |
| 1570 | continue; |
| 1571 | } |
| 1572 | |
| 1573 | break; |
| 1574 | } |
| 1575 | |
| 1576 | /* |
| 1577 | * Encode as a game ID. We do this by: |
| 1578 | * |
| 1579 | * - first going along the horizontal edges row by row, and |
| 1580 | * then the vertical edges column by column |
| 1581 | * - encoding the lengths of runs of edges and runs of |
| 1582 | * non-edges |
| 1583 | * - the decoder will reconstitute the region boundaries from |
| 1584 | * this and automatically number them the same way we did |
| 1585 | * - then we encode the initial region colours in a Slant-like |
| 1586 | * fashion (digits 0-3 interspersed with letters giving |
| 1587 | * lengths of runs of empty spaces). |
| 1588 | */ |
| 1589 | retlen = retsize = 0; |
| 1590 | ret = NULL; |
| 1591 | |
| 1592 | { |
| 1593 | int run, pv; |
| 1594 | |
| 1595 | /* |
| 1596 | * Start with a notional non-edge, so that there'll be an |
| 1597 | * explicit `a' to distinguish the case where we start with |
| 1598 | * an edge. |
| 1599 | */ |
| 1600 | run = 1; |
| 1601 | pv = 0; |
| 1602 | |
| 1603 | for (i = 0; i < w*(h-1) + (w-1)*h; i++) { |
| 1604 | int x, y, dx, dy, v; |
| 1605 | |
| 1606 | if (i < w*(h-1)) { |
| 1607 | /* Horizontal edge. */ |
| 1608 | y = i / w; |
| 1609 | x = i % w; |
| 1610 | dx = 0; |
| 1611 | dy = 1; |
| 1612 | } else { |
| 1613 | /* Vertical edge. */ |
| 1614 | x = (i - w*(h-1)) / h; |
| 1615 | y = (i - w*(h-1)) % h; |
| 1616 | dx = 1; |
| 1617 | dy = 0; |
| 1618 | } |
| 1619 | |
| 1620 | if (retlen + 10 >= retsize) { |
| 1621 | retsize = retlen + 256; |
| 1622 | ret = sresize(ret, retsize, char); |
| 1623 | } |
| 1624 | |
| 1625 | v = (map[y*w+x] != map[(y+dy)*w+(x+dx)]); |
| 1626 | |
| 1627 | if (pv != v) { |
| 1628 | ret[retlen++] = 'a'-1 + run; |
| 1629 | run = 1; |
| 1630 | pv = v; |
| 1631 | } else { |
| 1632 | /* |
| 1633 | * 'z' is a special case in this encoding. Rather |
| 1634 | * than meaning a run of 26 and a state switch, it |
| 1635 | * means a run of 25 and _no_ state switch, because |
| 1636 | * otherwise there'd be no way to encode runs of |
| 1637 | * more than 26. |
| 1638 | */ |
| 1639 | if (run == 25) { |
| 1640 | ret[retlen++] = 'z'; |
| 1641 | run = 0; |
| 1642 | } |
| 1643 | run++; |
| 1644 | } |
| 1645 | } |
| 1646 | |
| 1647 | ret[retlen++] = 'a'-1 + run; |
| 1648 | ret[retlen++] = ','; |
| 1649 | |
| 1650 | run = 0; |
| 1651 | for (i = 0; i < n; i++) { |
| 1652 | if (retlen + 10 >= retsize) { |
| 1653 | retsize = retlen + 256; |
| 1654 | ret = sresize(ret, retsize, char); |
| 1655 | } |
| 1656 | |
| 1657 | if (colouring[i] < 0) { |
| 1658 | /* |
| 1659 | * In _this_ encoding, 'z' is a run of 26, since |
| 1660 | * there's no implicit state switch after each run. |
| 1661 | * Confusingly different, but more compact. |
| 1662 | */ |
| 1663 | if (run == 26) { |
| 1664 | ret[retlen++] = 'z'; |
| 1665 | run = 0; |
| 1666 | } |
| 1667 | run++; |
| 1668 | } else { |
| 1669 | if (run > 0) |
| 1670 | ret[retlen++] = 'a'-1 + run; |
| 1671 | ret[retlen++] = '0' + colouring[i]; |
| 1672 | run = 0; |
| 1673 | } |
| 1674 | } |
| 1675 | if (run > 0) |
| 1676 | ret[retlen++] = 'a'-1 + run; |
| 1677 | ret[retlen] = '\0'; |
| 1678 | |
| 1679 | assert(retlen < retsize); |
| 1680 | } |
| 1681 | |
| 1682 | free_scratch(sc); |
| 1683 | sfree(regions); |
| 1684 | sfree(colouring2); |
| 1685 | sfree(colouring); |
| 1686 | sfree(graph); |
| 1687 | sfree(map); |
| 1688 | |
| 1689 | return ret; |
| 1690 | } |
| 1691 | |
| 1692 | static char *parse_edge_list(game_params *params, char **desc, int *map) |
| 1693 | { |
| 1694 | int w = params->w, h = params->h, wh = w*h, n = params->n; |
| 1695 | int i, k, pos, state; |
| 1696 | char *p = *desc; |
| 1697 | |
| 1698 | dsf_init(map+wh, wh); |
| 1699 | |
| 1700 | pos = -1; |
| 1701 | state = 0; |
| 1702 | |
| 1703 | /* |
| 1704 | * Parse the game description to get the list of edges, and |
| 1705 | * build up a disjoint set forest as we go (by identifying |
| 1706 | * pairs of squares whenever the edge list shows a non-edge). |
| 1707 | */ |
| 1708 | while (*p && *p != ',') { |
| 1709 | if (*p < 'a' || *p > 'z') |
| 1710 | return "Unexpected character in edge list"; |
| 1711 | if (*p == 'z') |
| 1712 | k = 25; |
| 1713 | else |
| 1714 | k = *p - 'a' + 1; |
| 1715 | while (k-- > 0) { |
| 1716 | int x, y, dx, dy; |
| 1717 | |
| 1718 | if (pos < 0) { |
| 1719 | pos++; |
| 1720 | continue; |
| 1721 | } else if (pos < w*(h-1)) { |
| 1722 | /* Horizontal edge. */ |
| 1723 | y = pos / w; |
| 1724 | x = pos % w; |
| 1725 | dx = 0; |
| 1726 | dy = 1; |
| 1727 | } else if (pos < 2*wh-w-h) { |
| 1728 | /* Vertical edge. */ |
| 1729 | x = (pos - w*(h-1)) / h; |
| 1730 | y = (pos - w*(h-1)) % h; |
| 1731 | dx = 1; |
| 1732 | dy = 0; |
| 1733 | } else |
| 1734 | return "Too much data in edge list"; |
| 1735 | if (!state) |
| 1736 | dsf_merge(map+wh, y*w+x, (y+dy)*w+(x+dx)); |
| 1737 | |
| 1738 | pos++; |
| 1739 | } |
| 1740 | if (*p != 'z') |
| 1741 | state = !state; |
| 1742 | p++; |
| 1743 | } |
| 1744 | assert(pos <= 2*wh-w-h); |
| 1745 | if (pos < 2*wh-w-h) |
| 1746 | return "Too little data in edge list"; |
| 1747 | |
| 1748 | /* |
| 1749 | * Now go through again and allocate region numbers. |
| 1750 | */ |
| 1751 | pos = 0; |
| 1752 | for (i = 0; i < wh; i++) |
| 1753 | map[i] = -1; |
| 1754 | for (i = 0; i < wh; i++) { |
| 1755 | k = dsf_canonify(map+wh, i); |
| 1756 | if (map[k] < 0) |
| 1757 | map[k] = pos++; |
| 1758 | map[i] = map[k]; |
| 1759 | } |
| 1760 | if (pos != n) |
| 1761 | return "Edge list defines the wrong number of regions"; |
| 1762 | |
| 1763 | *desc = p; |
| 1764 | |
| 1765 | return NULL; |
| 1766 | } |
| 1767 | |
| 1768 | static char *validate_desc(game_params *params, char *desc) |
| 1769 | { |
| 1770 | int w = params->w, h = params->h, wh = w*h, n = params->n; |
| 1771 | int area; |
| 1772 | int *map; |
| 1773 | char *ret; |
| 1774 | |
| 1775 | map = snewn(2*wh, int); |
| 1776 | ret = parse_edge_list(params, &desc, map); |
| 1777 | if (ret) |
| 1778 | return ret; |
| 1779 | sfree(map); |
| 1780 | |
| 1781 | if (*desc != ',') |
| 1782 | return "Expected comma before clue list"; |
| 1783 | desc++; /* eat comma */ |
| 1784 | |
| 1785 | area = 0; |
| 1786 | while (*desc) { |
| 1787 | if (*desc >= '0' && *desc < '0'+FOUR) |
| 1788 | area++; |
| 1789 | else if (*desc >= 'a' && *desc <= 'z') |
| 1790 | area += *desc - 'a' + 1; |
| 1791 | else |
| 1792 | return "Unexpected character in clue list"; |
| 1793 | desc++; |
| 1794 | } |
| 1795 | if (area < n) |
| 1796 | return "Too little data in clue list"; |
| 1797 | else if (area > n) |
| 1798 | return "Too much data in clue list"; |
| 1799 | |
| 1800 | return NULL; |
| 1801 | } |
| 1802 | |
| 1803 | static game_state *new_game(midend *me, game_params *params, char *desc) |
| 1804 | { |
| 1805 | int w = params->w, h = params->h, wh = w*h, n = params->n; |
| 1806 | int i, pos; |
| 1807 | char *p; |
| 1808 | game_state *state = snew(game_state); |
| 1809 | |
| 1810 | state->p = *params; |
| 1811 | state->colouring = snewn(n, int); |
| 1812 | for (i = 0; i < n; i++) |
| 1813 | state->colouring[i] = -1; |
| 1814 | state->pencil = snewn(n, int); |
| 1815 | for (i = 0; i < n; i++) |
| 1816 | state->pencil[i] = 0; |
| 1817 | |
| 1818 | state->completed = state->cheated = FALSE; |
| 1819 | |
| 1820 | state->map = snew(struct map); |
| 1821 | state->map->refcount = 1; |
| 1822 | state->map->map = snewn(wh*4, int); |
| 1823 | state->map->graph = snewn(n*n, int); |
| 1824 | state->map->n = n; |
| 1825 | state->map->immutable = snewn(n, int); |
| 1826 | for (i = 0; i < n; i++) |
| 1827 | state->map->immutable[i] = FALSE; |
| 1828 | |
| 1829 | p = desc; |
| 1830 | |
| 1831 | { |
| 1832 | char *ret; |
| 1833 | ret = parse_edge_list(params, &p, state->map->map); |
| 1834 | assert(!ret); |
| 1835 | } |
| 1836 | |
| 1837 | /* |
| 1838 | * Set up the other three quadrants in `map'. |
| 1839 | */ |
| 1840 | for (i = wh; i < 4*wh; i++) |
| 1841 | state->map->map[i] = state->map->map[i % wh]; |
| 1842 | |
| 1843 | assert(*p == ','); |
| 1844 | p++; |
| 1845 | |
| 1846 | /* |
| 1847 | * Now process the clue list. |
| 1848 | */ |
| 1849 | pos = 0; |
| 1850 | while (*p) { |
| 1851 | if (*p >= '0' && *p < '0'+FOUR) { |
| 1852 | state->colouring[pos] = *p - '0'; |
| 1853 | state->map->immutable[pos] = TRUE; |
| 1854 | pos++; |
| 1855 | } else { |
| 1856 | assert(*p >= 'a' && *p <= 'z'); |
| 1857 | pos += *p - 'a' + 1; |
| 1858 | } |
| 1859 | p++; |
| 1860 | } |
| 1861 | assert(pos == n); |
| 1862 | |
| 1863 | state->map->ngraph = gengraph(w, h, n, state->map->map, state->map->graph); |
| 1864 | |
| 1865 | /* |
| 1866 | * Attempt to smooth out some of the more jagged region |
| 1867 | * outlines by the judicious use of diagonally divided squares. |
| 1868 | */ |
| 1869 | { |
| 1870 | random_state *rs = random_new(desc, strlen(desc)); |
| 1871 | int *squares = snewn(wh, int); |
| 1872 | int done_something; |
| 1873 | |
| 1874 | for (i = 0; i < wh; i++) |
| 1875 | squares[i] = i; |
| 1876 | shuffle(squares, wh, sizeof(*squares), rs); |
| 1877 | |
| 1878 | do { |
| 1879 | done_something = FALSE; |
| 1880 | for (i = 0; i < wh; i++) { |
| 1881 | int y = squares[i] / w, x = squares[i] % w; |
| 1882 | int c = state->map->map[y*w+x]; |
| 1883 | int tc, bc, lc, rc; |
| 1884 | |
| 1885 | if (x == 0 || x == w-1 || y == 0 || y == h-1) |
| 1886 | continue; |
| 1887 | |
| 1888 | if (state->map->map[TE * wh + y*w+x] != |
| 1889 | state->map->map[BE * wh + y*w+x]) |
| 1890 | continue; |
| 1891 | |
| 1892 | tc = state->map->map[BE * wh + (y-1)*w+x]; |
| 1893 | bc = state->map->map[TE * wh + (y+1)*w+x]; |
| 1894 | lc = state->map->map[RE * wh + y*w+(x-1)]; |
| 1895 | rc = state->map->map[LE * wh + y*w+(x+1)]; |
| 1896 | |
| 1897 | /* |
| 1898 | * If this square is adjacent on two sides to one |
| 1899 | * region and on the other two sides to the other |
| 1900 | * region, and is itself one of the two regions, we can |
| 1901 | * adjust it so that it's a diagonal. |
| 1902 | */ |
| 1903 | if (tc != bc && (tc == c || bc == c)) { |
| 1904 | if ((lc == tc && rc == bc) || |
| 1905 | (lc == bc && rc == tc)) { |
| 1906 | state->map->map[TE * wh + y*w+x] = tc; |
| 1907 | state->map->map[BE * wh + y*w+x] = bc; |
| 1908 | state->map->map[LE * wh + y*w+x] = lc; |
| 1909 | state->map->map[RE * wh + y*w+x] = rc; |
| 1910 | done_something = TRUE; |
| 1911 | } |
| 1912 | } |
| 1913 | } |
| 1914 | } while (done_something); |
| 1915 | sfree(squares); |
| 1916 | random_free(rs); |
| 1917 | } |
| 1918 | |
| 1919 | /* |
| 1920 | * Analyse the map to find a canonical line segment |
| 1921 | * corresponding to each edge, and a canonical point |
| 1922 | * corresponding to each region. The former are where we'll |
| 1923 | * eventually put error markers; the latter are where we'll put |
| 1924 | * per-region flags such as numbers (when in diagnostic mode). |
| 1925 | */ |
| 1926 | { |
| 1927 | int *bestx, *besty, *an, pass; |
| 1928 | float *ax, *ay, *best; |
| 1929 | |
| 1930 | ax = snewn(state->map->ngraph + n, float); |
| 1931 | ay = snewn(state->map->ngraph + n, float); |
| 1932 | an = snewn(state->map->ngraph + n, int); |
| 1933 | bestx = snewn(state->map->ngraph + n, int); |
| 1934 | besty = snewn(state->map->ngraph + n, int); |
| 1935 | best = snewn(state->map->ngraph + n, float); |
| 1936 | |
| 1937 | for (i = 0; i < state->map->ngraph + n; i++) { |
| 1938 | bestx[i] = besty[i] = -1; |
| 1939 | best[i] = 2*(w+h)+1; |
| 1940 | ax[i] = ay[i] = 0.0F; |
| 1941 | an[i] = 0; |
| 1942 | } |
| 1943 | |
| 1944 | /* |
| 1945 | * We make two passes over the map, finding all the line |
| 1946 | * segments separating regions and all the suitable points |
| 1947 | * within regions. In the first pass, we compute the |
| 1948 | * _average_ x and y coordinate of all the points in a |
| 1949 | * given class; in the second pass, for each such average |
| 1950 | * point, we find the candidate closest to it and call that |
| 1951 | * canonical. |
| 1952 | * |
| 1953 | * Line segments are considered to have coordinates in |
| 1954 | * their centre. Thus, at least one coordinate for any line |
| 1955 | * segment is always something-and-a-half; so we store our |
| 1956 | * coordinates as twice their normal value. |
| 1957 | */ |
| 1958 | for (pass = 0; pass < 2; pass++) { |
| 1959 | int x, y; |
| 1960 | |
| 1961 | for (y = 0; y < h; y++) |
| 1962 | for (x = 0; x < w; x++) { |
| 1963 | int ex[4], ey[4], ea[4], eb[4], en = 0; |
| 1964 | |
| 1965 | /* |
| 1966 | * Look for an edge to the right of this |
| 1967 | * square, an edge below it, and an edge in the |
| 1968 | * middle of it. Also look to see if the point |
| 1969 | * at the bottom right of this square is on an |
| 1970 | * edge (and isn't a place where more than two |
| 1971 | * regions meet). |
| 1972 | */ |
| 1973 | if (x+1 < w) { |
| 1974 | /* right edge */ |
| 1975 | ea[en] = state->map->map[RE * wh + y*w+x]; |
| 1976 | eb[en] = state->map->map[LE * wh + y*w+(x+1)]; |
| 1977 | ex[en] = (x+1)*2; |
| 1978 | ey[en] = y*2+1; |
| 1979 | en++; |
| 1980 | } |
| 1981 | if (y+1 < h) { |
| 1982 | /* bottom edge */ |
| 1983 | ea[en] = state->map->map[BE * wh + y*w+x]; |
| 1984 | eb[en] = state->map->map[TE * wh + (y+1)*w+x]; |
| 1985 | ex[en] = x*2+1; |
| 1986 | ey[en] = (y+1)*2; |
| 1987 | en++; |
| 1988 | } |
| 1989 | /* diagonal edge */ |
| 1990 | ea[en] = state->map->map[TE * wh + y*w+x]; |
| 1991 | eb[en] = state->map->map[BE * wh + y*w+x]; |
| 1992 | ex[en] = x*2+1; |
| 1993 | ey[en] = y*2+1; |
| 1994 | en++; |
| 1995 | |
| 1996 | if (x+1 < w && y+1 < h) { |
| 1997 | /* bottom right corner */ |
| 1998 | int oct[8], othercol, nchanges; |
| 1999 | oct[0] = state->map->map[RE * wh + y*w+x]; |
| 2000 | oct[1] = state->map->map[LE * wh + y*w+(x+1)]; |
| 2001 | oct[2] = state->map->map[BE * wh + y*w+(x+1)]; |
| 2002 | oct[3] = state->map->map[TE * wh + (y+1)*w+(x+1)]; |
| 2003 | oct[4] = state->map->map[LE * wh + (y+1)*w+(x+1)]; |
| 2004 | oct[5] = state->map->map[RE * wh + (y+1)*w+x]; |
| 2005 | oct[6] = state->map->map[TE * wh + (y+1)*w+x]; |
| 2006 | oct[7] = state->map->map[BE * wh + y*w+x]; |
| 2007 | |
| 2008 | othercol = -1; |
| 2009 | nchanges = 0; |
| 2010 | for (i = 0; i < 8; i++) { |
| 2011 | if (oct[i] != oct[0]) { |
| 2012 | if (othercol < 0) |
| 2013 | othercol = oct[i]; |
| 2014 | else if (othercol != oct[i]) |
| 2015 | break; /* three colours at this point */ |
| 2016 | } |
| 2017 | if (oct[i] != oct[(i+1) & 7]) |
| 2018 | nchanges++; |
| 2019 | } |
| 2020 | |
| 2021 | /* |
| 2022 | * Now if there are exactly two regions at |
| 2023 | * this point (not one, and not three or |
| 2024 | * more), and only two changes around the |
| 2025 | * loop, then this is a valid place to put |
| 2026 | * an error marker. |
| 2027 | */ |
| 2028 | if (i == 8 && othercol >= 0 && nchanges == 2) { |
| 2029 | ea[en] = oct[0]; |
| 2030 | eb[en] = othercol; |
| 2031 | ex[en] = (x+1)*2; |
| 2032 | ey[en] = (y+1)*2; |
| 2033 | en++; |
| 2034 | } |
| 2035 | |
| 2036 | /* |
| 2037 | * If there's exactly _one_ region at this |
| 2038 | * point, on the other hand, it's a valid |
| 2039 | * place to put a region centre. |
| 2040 | */ |
| 2041 | if (othercol < 0) { |
| 2042 | ea[en] = eb[en] = oct[0]; |
| 2043 | ex[en] = (x+1)*2; |
| 2044 | ey[en] = (y+1)*2; |
| 2045 | en++; |
| 2046 | } |
| 2047 | } |
| 2048 | |
| 2049 | /* |
| 2050 | * Now process the points we've found, one by |
| 2051 | * one. |
| 2052 | */ |
| 2053 | for (i = 0; i < en; i++) { |
| 2054 | int emin = min(ea[i], eb[i]); |
| 2055 | int emax = max(ea[i], eb[i]); |
| 2056 | int gindex; |
| 2057 | |
| 2058 | if (emin != emax) { |
| 2059 | /* Graph edge */ |
| 2060 | gindex = |
| 2061 | graph_edge_index(state->map->graph, n, |
| 2062 | state->map->ngraph, emin, |
| 2063 | emax); |
| 2064 | } else { |
| 2065 | /* Region number */ |
| 2066 | gindex = state->map->ngraph + emin; |
| 2067 | } |
| 2068 | |
| 2069 | assert(gindex >= 0); |
| 2070 | |
| 2071 | if (pass == 0) { |
| 2072 | /* |
| 2073 | * In pass 0, accumulate the values |
| 2074 | * we'll use to compute the average |
| 2075 | * positions. |
| 2076 | */ |
| 2077 | ax[gindex] += ex[i]; |
| 2078 | ay[gindex] += ey[i]; |
| 2079 | an[gindex] += 1.0F; |
| 2080 | } else { |
| 2081 | /* |
| 2082 | * In pass 1, work out whether this |
| 2083 | * point is closer to the average than |
| 2084 | * the last one we've seen. |
| 2085 | */ |
| 2086 | float dx, dy, d; |
| 2087 | |
| 2088 | assert(an[gindex] > 0); |
| 2089 | dx = ex[i] - ax[gindex]; |
| 2090 | dy = ey[i] - ay[gindex]; |
| 2091 | d = sqrt(dx*dx + dy*dy); |
| 2092 | if (d < best[gindex]) { |
| 2093 | best[gindex] = d; |
| 2094 | bestx[gindex] = ex[i]; |
| 2095 | besty[gindex] = ey[i]; |
| 2096 | } |
| 2097 | } |
| 2098 | } |
| 2099 | } |
| 2100 | |
| 2101 | if (pass == 0) { |
| 2102 | for (i = 0; i < state->map->ngraph + n; i++) |
| 2103 | if (an[i] > 0) { |
| 2104 | ax[i] /= an[i]; |
| 2105 | ay[i] /= an[i]; |
| 2106 | } |
| 2107 | } |
| 2108 | } |
| 2109 | |
| 2110 | state->map->edgex = snewn(state->map->ngraph, int); |
| 2111 | state->map->edgey = snewn(state->map->ngraph, int); |
| 2112 | memcpy(state->map->edgex, bestx, state->map->ngraph * sizeof(int)); |
| 2113 | memcpy(state->map->edgey, besty, state->map->ngraph * sizeof(int)); |
| 2114 | |
| 2115 | state->map->regionx = snewn(n, int); |
| 2116 | state->map->regiony = snewn(n, int); |
| 2117 | memcpy(state->map->regionx, bestx + state->map->ngraph, n*sizeof(int)); |
| 2118 | memcpy(state->map->regiony, besty + state->map->ngraph, n*sizeof(int)); |
| 2119 | |
| 2120 | for (i = 0; i < state->map->ngraph; i++) |
| 2121 | if (state->map->edgex[i] < 0) { |
| 2122 | /* Find the other representation of this edge. */ |
| 2123 | int e = state->map->graph[i]; |
| 2124 | int iprime = graph_edge_index(state->map->graph, n, |
| 2125 | state->map->ngraph, e%n, e/n); |
| 2126 | assert(state->map->edgex[iprime] >= 0); |
| 2127 | state->map->edgex[i] = state->map->edgex[iprime]; |
| 2128 | state->map->edgey[i] = state->map->edgey[iprime]; |
| 2129 | } |
| 2130 | |
| 2131 | sfree(ax); |
| 2132 | sfree(ay); |
| 2133 | sfree(an); |
| 2134 | sfree(best); |
| 2135 | sfree(bestx); |
| 2136 | sfree(besty); |
| 2137 | } |
| 2138 | |
| 2139 | return state; |
| 2140 | } |
| 2141 | |
| 2142 | static game_state *dup_game(game_state *state) |
| 2143 | { |
| 2144 | game_state *ret = snew(game_state); |
| 2145 | |
| 2146 | ret->p = state->p; |
| 2147 | ret->colouring = snewn(state->p.n, int); |
| 2148 | memcpy(ret->colouring, state->colouring, state->p.n * sizeof(int)); |
| 2149 | ret->pencil = snewn(state->p.n, int); |
| 2150 | memcpy(ret->pencil, state->pencil, state->p.n * sizeof(int)); |
| 2151 | ret->map = state->map; |
| 2152 | ret->map->refcount++; |
| 2153 | ret->completed = state->completed; |
| 2154 | ret->cheated = state->cheated; |
| 2155 | |
| 2156 | return ret; |
| 2157 | } |
| 2158 | |
| 2159 | static void free_game(game_state *state) |
| 2160 | { |
| 2161 | if (--state->map->refcount <= 0) { |
| 2162 | sfree(state->map->map); |
| 2163 | sfree(state->map->graph); |
| 2164 | sfree(state->map->immutable); |
| 2165 | sfree(state->map->edgex); |
| 2166 | sfree(state->map->edgey); |
| 2167 | sfree(state->map->regionx); |
| 2168 | sfree(state->map->regiony); |
| 2169 | sfree(state->map); |
| 2170 | } |
| 2171 | sfree(state->pencil); |
| 2172 | sfree(state->colouring); |
| 2173 | sfree(state); |
| 2174 | } |
| 2175 | |
| 2176 | static char *solve_game(game_state *state, game_state *currstate, |
| 2177 | char *aux, char **error) |
| 2178 | { |
| 2179 | if (!aux) { |
| 2180 | /* |
| 2181 | * Use the solver. |
| 2182 | */ |
| 2183 | int *colouring; |
| 2184 | struct solver_scratch *sc; |
| 2185 | int sret; |
| 2186 | int i; |
| 2187 | char *ret, buf[80]; |
| 2188 | int retlen, retsize; |
| 2189 | |
| 2190 | colouring = snewn(state->map->n, int); |
| 2191 | memcpy(colouring, state->colouring, state->map->n * sizeof(int)); |
| 2192 | |
| 2193 | sc = new_scratch(state->map->graph, state->map->n, state->map->ngraph); |
| 2194 | sret = map_solver(sc, state->map->graph, state->map->n, |
| 2195 | state->map->ngraph, colouring, DIFFCOUNT-1); |
| 2196 | free_scratch(sc); |
| 2197 | |
| 2198 | if (sret != 1) { |
| 2199 | sfree(colouring); |
| 2200 | if (sret == 0) |
| 2201 | *error = "Puzzle is inconsistent"; |
| 2202 | else |
| 2203 | *error = "Unable to find a unique solution for this puzzle"; |
| 2204 | return NULL; |
| 2205 | } |
| 2206 | |
| 2207 | retsize = 64; |
| 2208 | ret = snewn(retsize, char); |
| 2209 | strcpy(ret, "S"); |
| 2210 | retlen = 1; |
| 2211 | |
| 2212 | for (i = 0; i < state->map->n; i++) { |
| 2213 | int len; |
| 2214 | |
| 2215 | assert(colouring[i] >= 0); |
| 2216 | if (colouring[i] == currstate->colouring[i]) |
| 2217 | continue; |
| 2218 | assert(!state->map->immutable[i]); |
| 2219 | |
| 2220 | len = sprintf(buf, ";%d:%d", colouring[i], i); |
| 2221 | if (retlen + len >= retsize) { |
| 2222 | retsize = retlen + len + 256; |
| 2223 | ret = sresize(ret, retsize, char); |
| 2224 | } |
| 2225 | strcpy(ret + retlen, buf); |
| 2226 | retlen += len; |
| 2227 | } |
| 2228 | |
| 2229 | sfree(colouring); |
| 2230 | |
| 2231 | return ret; |
| 2232 | } |
| 2233 | return dupstr(aux); |
| 2234 | } |
| 2235 | |
| 2236 | static char *game_text_format(game_state *state) |
| 2237 | { |
| 2238 | return NULL; |
| 2239 | } |
| 2240 | |
| 2241 | struct game_ui { |
| 2242 | /* |
| 2243 | * drag_colour: |
| 2244 | * |
| 2245 | * - -2 means no drag currently active. |
| 2246 | * - >=0 means we're dragging a solid colour. |
| 2247 | * - -1 means we're dragging a blank space, and drag_pencil |
| 2248 | * might or might not add some pencil-mark stipples to that. |
| 2249 | */ |
| 2250 | int drag_colour; |
| 2251 | int drag_pencil; |
| 2252 | int dragx, dragy; |
| 2253 | int show_numbers; |
| 2254 | }; |
| 2255 | |
| 2256 | static game_ui *new_ui(game_state *state) |
| 2257 | { |
| 2258 | game_ui *ui = snew(game_ui); |
| 2259 | ui->dragx = ui->dragy = -1; |
| 2260 | ui->drag_colour = -2; |
| 2261 | ui->show_numbers = FALSE; |
| 2262 | return ui; |
| 2263 | } |
| 2264 | |
| 2265 | static void free_ui(game_ui *ui) |
| 2266 | { |
| 2267 | sfree(ui); |
| 2268 | } |
| 2269 | |
| 2270 | static char *encode_ui(game_ui *ui) |
| 2271 | { |
| 2272 | return NULL; |
| 2273 | } |
| 2274 | |
| 2275 | static void decode_ui(game_ui *ui, char *encoding) |
| 2276 | { |
| 2277 | } |
| 2278 | |
| 2279 | static void game_changed_state(game_ui *ui, game_state *oldstate, |
| 2280 | game_state *newstate) |
| 2281 | { |
| 2282 | } |
| 2283 | |
| 2284 | struct game_drawstate { |
| 2285 | int tilesize; |
| 2286 | unsigned long *drawn, *todraw; |
| 2287 | int started; |
| 2288 | int dragx, dragy, drag_visible; |
| 2289 | blitter *bl; |
| 2290 | }; |
| 2291 | |
| 2292 | /* Flags in `drawn'. */ |
| 2293 | #define ERR_BASE 0x00800000L |
| 2294 | #define ERR_MASK 0xFF800000L |
| 2295 | #define PENCIL_T_BASE 0x00080000L |
| 2296 | #define PENCIL_T_MASK 0x00780000L |
| 2297 | #define PENCIL_B_BASE 0x00008000L |
| 2298 | #define PENCIL_B_MASK 0x00078000L |
| 2299 | #define PENCIL_MASK 0x007F8000L |
| 2300 | #define SHOW_NUMBERS 0x00004000L |
| 2301 | |
| 2302 | #define TILESIZE (ds->tilesize) |
| 2303 | #define BORDER (TILESIZE) |
| 2304 | #define COORD(x) ( (x) * TILESIZE + BORDER ) |
| 2305 | #define FROMCOORD(x) ( ((x) - BORDER + TILESIZE) / TILESIZE - 1 ) |
| 2306 | |
| 2307 | static int region_from_coords(game_state *state, game_drawstate *ds, |
| 2308 | int x, int y) |
| 2309 | { |
| 2310 | int w = state->p.w, h = state->p.h, wh = w*h /*, n = state->p.n */; |
| 2311 | int tx = FROMCOORD(x), ty = FROMCOORD(y); |
| 2312 | int dx = x - COORD(tx), dy = y - COORD(ty); |
| 2313 | int quadrant; |
| 2314 | |
| 2315 | if (tx < 0 || tx >= w || ty < 0 || ty >= h) |
| 2316 | return -1; /* border */ |
| 2317 | |
| 2318 | quadrant = 2 * (dx > dy) + (TILESIZE - dx > dy); |
| 2319 | quadrant = (quadrant == 0 ? BE : |
| 2320 | quadrant == 1 ? LE : |
| 2321 | quadrant == 2 ? RE : TE); |
| 2322 | |
| 2323 | return state->map->map[quadrant * wh + ty*w+tx]; |
| 2324 | } |
| 2325 | |
| 2326 | static char *interpret_move(game_state *state, game_ui *ui, game_drawstate *ds, |
| 2327 | int x, int y, int button) |
| 2328 | { |
| 2329 | char *bufp, buf[256]; |
| 2330 | |
| 2331 | /* |
| 2332 | * Enable or disable numeric labels on regions. |
| 2333 | */ |
| 2334 | if (button == 'l' || button == 'L') { |
| 2335 | ui->show_numbers = !ui->show_numbers; |
| 2336 | return ""; |
| 2337 | } |
| 2338 | |
| 2339 | if (button == LEFT_BUTTON || button == RIGHT_BUTTON) { |
| 2340 | int r = region_from_coords(state, ds, x, y); |
| 2341 | |
| 2342 | if (r >= 0) { |
| 2343 | ui->drag_colour = state->colouring[r]; |
| 2344 | ui->drag_pencil = state->pencil[r]; |
| 2345 | if (ui->drag_colour >= 0) |
| 2346 | ui->drag_pencil = 0; /* should be already, but double-check */ |
| 2347 | } else { |
| 2348 | ui->drag_colour = -1; |
| 2349 | ui->drag_pencil = 0; |
| 2350 | } |
| 2351 | ui->dragx = x; |
| 2352 | ui->dragy = y; |
| 2353 | return ""; |
| 2354 | } |
| 2355 | |
| 2356 | if ((button == LEFT_DRAG || button == RIGHT_DRAG) && |
| 2357 | ui->drag_colour > -2) { |
| 2358 | ui->dragx = x; |
| 2359 | ui->dragy = y; |
| 2360 | return ""; |
| 2361 | } |
| 2362 | |
| 2363 | if ((button == LEFT_RELEASE || button == RIGHT_RELEASE) && |
| 2364 | ui->drag_colour > -2) { |
| 2365 | int r = region_from_coords(state, ds, x, y); |
| 2366 | int c = ui->drag_colour; |
| 2367 | int p = ui->drag_pencil; |
| 2368 | int oldp; |
| 2369 | |
| 2370 | /* |
| 2371 | * Cancel the drag, whatever happens. |
| 2372 | */ |
| 2373 | ui->drag_colour = -2; |
| 2374 | ui->dragx = ui->dragy = -1; |
| 2375 | |
| 2376 | if (r < 0) |
| 2377 | return ""; /* drag into border; do nothing else */ |
| 2378 | |
| 2379 | if (state->map->immutable[r]) |
| 2380 | return ""; /* can't change this region */ |
| 2381 | |
| 2382 | if (state->colouring[r] == c && state->pencil[r] == p) |
| 2383 | return ""; /* don't _need_ to change this region */ |
| 2384 | |
| 2385 | if (button == RIGHT_RELEASE) { |
| 2386 | if (state->colouring[r] >= 0) { |
| 2387 | /* Can't pencil on a coloured region */ |
| 2388 | return ""; |
| 2389 | } else if (c >= 0) { |
| 2390 | /* Right-dragging from colour to blank toggles one pencil */ |
| 2391 | p = state->pencil[r] ^ (1 << c); |
| 2392 | c = -1; |
| 2393 | } |
| 2394 | /* Otherwise, right-dragging from blank to blank is equivalent |
| 2395 | * to left-dragging. */ |
| 2396 | } |
| 2397 | |
| 2398 | bufp = buf; |
| 2399 | oldp = state->pencil[r]; |
| 2400 | if (c != state->colouring[r]) { |
| 2401 | bufp += sprintf(bufp, ";%c:%d", (int)(c < 0 ? 'C' : '0' + c), r); |
| 2402 | if (c >= 0) |
| 2403 | oldp = 0; |
| 2404 | } |
| 2405 | if (p != oldp) { |
| 2406 | int i; |
| 2407 | for (i = 0; i < FOUR; i++) |
| 2408 | if ((oldp ^ p) & (1 << i)) |
| 2409 | bufp += sprintf(bufp, ";p%c:%d", (int)('0' + i), r); |
| 2410 | } |
| 2411 | |
| 2412 | return dupstr(buf+1); /* ignore first semicolon */ |
| 2413 | } |
| 2414 | |
| 2415 | return NULL; |
| 2416 | } |
| 2417 | |
| 2418 | static game_state *execute_move(game_state *state, char *move) |
| 2419 | { |
| 2420 | int n = state->p.n; |
| 2421 | game_state *ret = dup_game(state); |
| 2422 | int c, k, adv, i; |
| 2423 | |
| 2424 | while (*move) { |
| 2425 | int pencil = FALSE; |
| 2426 | |
| 2427 | c = *move; |
| 2428 | if (c == 'p') { |
| 2429 | pencil = TRUE; |
| 2430 | c = *++move; |
| 2431 | } |
| 2432 | if ((c == 'C' || (c >= '0' && c < '0'+FOUR)) && |
| 2433 | sscanf(move+1, ":%d%n", &k, &adv) == 1 && |
| 2434 | k >= 0 && k < state->p.n) { |
| 2435 | move += 1 + adv; |
| 2436 | if (pencil) { |
| 2437 | if (ret->colouring[k] >= 0) { |
| 2438 | free_game(ret); |
| 2439 | return NULL; |
| 2440 | } |
| 2441 | if (c == 'C') |
| 2442 | ret->pencil[k] = 0; |
| 2443 | else |
| 2444 | ret->pencil[k] ^= 1 << (c - '0'); |
| 2445 | } else { |
| 2446 | ret->colouring[k] = (c == 'C' ? -1 : c - '0'); |
| 2447 | ret->pencil[k] = 0; |
| 2448 | } |
| 2449 | } else if (*move == 'S') { |
| 2450 | move++; |
| 2451 | ret->cheated = TRUE; |
| 2452 | } else { |
| 2453 | free_game(ret); |
| 2454 | return NULL; |
| 2455 | } |
| 2456 | |
| 2457 | if (*move && *move != ';') { |
| 2458 | free_game(ret); |
| 2459 | return NULL; |
| 2460 | } |
| 2461 | if (*move) |
| 2462 | move++; |
| 2463 | } |
| 2464 | |
| 2465 | /* |
| 2466 | * Check for completion. |
| 2467 | */ |
| 2468 | if (!ret->completed) { |
| 2469 | int ok = TRUE; |
| 2470 | |
| 2471 | for (i = 0; i < n; i++) |
| 2472 | if (ret->colouring[i] < 0) { |
| 2473 | ok = FALSE; |
| 2474 | break; |
| 2475 | } |
| 2476 | |
| 2477 | if (ok) { |
| 2478 | for (i = 0; i < ret->map->ngraph; i++) { |
| 2479 | int j = ret->map->graph[i] / n; |
| 2480 | int k = ret->map->graph[i] % n; |
| 2481 | if (ret->colouring[j] == ret->colouring[k]) { |
| 2482 | ok = FALSE; |
| 2483 | break; |
| 2484 | } |
| 2485 | } |
| 2486 | } |
| 2487 | |
| 2488 | if (ok) |
| 2489 | ret->completed = TRUE; |
| 2490 | } |
| 2491 | |
| 2492 | return ret; |
| 2493 | } |
| 2494 | |
| 2495 | /* ---------------------------------------------------------------------- |
| 2496 | * Drawing routines. |
| 2497 | */ |
| 2498 | |
| 2499 | static void game_compute_size(game_params *params, int tilesize, |
| 2500 | int *x, int *y) |
| 2501 | { |
| 2502 | /* Ick: fake up `ds->tilesize' for macro expansion purposes */ |
| 2503 | struct { int tilesize; } ads, *ds = &ads; |
| 2504 | ads.tilesize = tilesize; |
| 2505 | |
| 2506 | *x = params->w * TILESIZE + 2 * BORDER + 1; |
| 2507 | *y = params->h * TILESIZE + 2 * BORDER + 1; |
| 2508 | } |
| 2509 | |
| 2510 | static void game_set_size(drawing *dr, game_drawstate *ds, |
| 2511 | game_params *params, int tilesize) |
| 2512 | { |
| 2513 | ds->tilesize = tilesize; |
| 2514 | |
| 2515 | assert(!ds->bl); /* set_size is never called twice */ |
| 2516 | ds->bl = blitter_new(dr, TILESIZE+3, TILESIZE+3); |
| 2517 | } |
| 2518 | |
| 2519 | const float map_colours[FOUR][3] = { |
| 2520 | {0.7F, 0.5F, 0.4F}, |
| 2521 | {0.8F, 0.7F, 0.4F}, |
| 2522 | {0.5F, 0.6F, 0.4F}, |
| 2523 | {0.55F, 0.45F, 0.35F}, |
| 2524 | }; |
| 2525 | const int map_hatching[FOUR] = { |
| 2526 | HATCH_VERT, HATCH_SLASH, HATCH_HORIZ, HATCH_BACKSLASH |
| 2527 | }; |
| 2528 | |
| 2529 | static float *game_colours(frontend *fe, int *ncolours) |
| 2530 | { |
| 2531 | float *ret = snewn(3 * NCOLOURS, float); |
| 2532 | |
| 2533 | frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]); |
| 2534 | |
| 2535 | ret[COL_GRID * 3 + 0] = 0.0F; |
| 2536 | ret[COL_GRID * 3 + 1] = 0.0F; |
| 2537 | ret[COL_GRID * 3 + 2] = 0.0F; |
| 2538 | |
| 2539 | memcpy(ret + COL_0 * 3, map_colours[0], 3 * sizeof(float)); |
| 2540 | memcpy(ret + COL_1 * 3, map_colours[1], 3 * sizeof(float)); |
| 2541 | memcpy(ret + COL_2 * 3, map_colours[2], 3 * sizeof(float)); |
| 2542 | memcpy(ret + COL_3 * 3, map_colours[3], 3 * sizeof(float)); |
| 2543 | |
| 2544 | ret[COL_ERROR * 3 + 0] = 1.0F; |
| 2545 | ret[COL_ERROR * 3 + 1] = 0.0F; |
| 2546 | ret[COL_ERROR * 3 + 2] = 0.0F; |
| 2547 | |
| 2548 | ret[COL_ERRTEXT * 3 + 0] = 1.0F; |
| 2549 | ret[COL_ERRTEXT * 3 + 1] = 1.0F; |
| 2550 | ret[COL_ERRTEXT * 3 + 2] = 1.0F; |
| 2551 | |
| 2552 | *ncolours = NCOLOURS; |
| 2553 | return ret; |
| 2554 | } |
| 2555 | |
| 2556 | static game_drawstate *game_new_drawstate(drawing *dr, game_state *state) |
| 2557 | { |
| 2558 | struct game_drawstate *ds = snew(struct game_drawstate); |
| 2559 | int i; |
| 2560 | |
| 2561 | ds->tilesize = 0; |
| 2562 | ds->drawn = snewn(state->p.w * state->p.h, unsigned long); |
| 2563 | for (i = 0; i < state->p.w * state->p.h; i++) |
| 2564 | ds->drawn[i] = 0xFFFFL; |
| 2565 | ds->todraw = snewn(state->p.w * state->p.h, unsigned long); |
| 2566 | ds->started = FALSE; |
| 2567 | ds->bl = NULL; |
| 2568 | ds->drag_visible = FALSE; |
| 2569 | ds->dragx = ds->dragy = -1; |
| 2570 | |
| 2571 | return ds; |
| 2572 | } |
| 2573 | |
| 2574 | static void game_free_drawstate(drawing *dr, game_drawstate *ds) |
| 2575 | { |
| 2576 | sfree(ds->drawn); |
| 2577 | sfree(ds->todraw); |
| 2578 | if (ds->bl) |
| 2579 | blitter_free(dr, ds->bl); |
| 2580 | sfree(ds); |
| 2581 | } |
| 2582 | |
| 2583 | static void draw_error(drawing *dr, game_drawstate *ds, int x, int y) |
| 2584 | { |
| 2585 | int coords[8]; |
| 2586 | int yext, xext; |
| 2587 | |
| 2588 | /* |
| 2589 | * Draw a diamond. |
| 2590 | */ |
| 2591 | coords[0] = x - TILESIZE*2/5; |
| 2592 | coords[1] = y; |
| 2593 | coords[2] = x; |
| 2594 | coords[3] = y - TILESIZE*2/5; |
| 2595 | coords[4] = x + TILESIZE*2/5; |
| 2596 | coords[5] = y; |
| 2597 | coords[6] = x; |
| 2598 | coords[7] = y + TILESIZE*2/5; |
| 2599 | draw_polygon(dr, coords, 4, COL_ERROR, COL_GRID); |
| 2600 | |
| 2601 | /* |
| 2602 | * Draw an exclamation mark in the diamond. This turns out to |
| 2603 | * look unpleasantly off-centre if done via draw_text, so I do |
| 2604 | * it by hand on the basis that exclamation marks aren't that |
| 2605 | * difficult to draw... |
| 2606 | */ |
| 2607 | xext = TILESIZE/16; |
| 2608 | yext = TILESIZE*2/5 - (xext*2+2); |
| 2609 | draw_rect(dr, x-xext, y-yext, xext*2+1, yext*2+1 - (xext*3), |
| 2610 | COL_ERRTEXT); |
| 2611 | draw_rect(dr, x-xext, y+yext-xext*2+1, xext*2+1, xext*2, COL_ERRTEXT); |
| 2612 | } |
| 2613 | |
| 2614 | static void draw_square(drawing *dr, game_drawstate *ds, |
| 2615 | game_params *params, struct map *map, |
| 2616 | int x, int y, unsigned long v) |
| 2617 | { |
| 2618 | int w = params->w, h = params->h, wh = w*h; |
| 2619 | int tv, bv, xo, yo, i, j, oldj; |
| 2620 | unsigned long errs, pencil, show_numbers; |
| 2621 | |
| 2622 | errs = v & ERR_MASK; |
| 2623 | v &= ~ERR_MASK; |
| 2624 | pencil = v & PENCIL_MASK; |
| 2625 | v &= ~PENCIL_MASK; |
| 2626 | show_numbers = v & SHOW_NUMBERS; |
| 2627 | v &= ~SHOW_NUMBERS; |
| 2628 | tv = v / FIVE; |
| 2629 | bv = v % FIVE; |
| 2630 | |
| 2631 | clip(dr, COORD(x), COORD(y), TILESIZE, TILESIZE); |
| 2632 | |
| 2633 | /* |
| 2634 | * Draw the region colour. |
| 2635 | */ |
| 2636 | draw_rect(dr, COORD(x), COORD(y), TILESIZE, TILESIZE, |
| 2637 | (tv == FOUR ? COL_BACKGROUND : COL_0 + tv)); |
| 2638 | /* |
| 2639 | * Draw the second region colour, if this is a diagonally |
| 2640 | * divided square. |
| 2641 | */ |
| 2642 | if (map->map[TE * wh + y*w+x] != map->map[BE * wh + y*w+x]) { |
| 2643 | int coords[6]; |
| 2644 | coords[0] = COORD(x)-1; |
| 2645 | coords[1] = COORD(y+1)+1; |
| 2646 | if (map->map[LE * wh + y*w+x] == map->map[TE * wh + y*w+x]) |
| 2647 | coords[2] = COORD(x+1)+1; |
| 2648 | else |
| 2649 | coords[2] = COORD(x)-1; |
| 2650 | coords[3] = COORD(y)-1; |
| 2651 | coords[4] = COORD(x+1)+1; |
| 2652 | coords[5] = COORD(y+1)+1; |
| 2653 | draw_polygon(dr, coords, 3, |
| 2654 | (bv == FOUR ? COL_BACKGROUND : COL_0 + bv), COL_GRID); |
| 2655 | } |
| 2656 | |
| 2657 | /* |
| 2658 | * Draw `pencil marks'. Currently we arrange these in a square |
| 2659 | * formation, which means we may be in trouble if the value of |
| 2660 | * FOUR changes later... |
| 2661 | */ |
| 2662 | assert(FOUR == 4); |
| 2663 | for (yo = 0; yo < 4; yo++) |
| 2664 | for (xo = 0; xo < 4; xo++) { |
| 2665 | int te = map->map[TE * wh + y*w+x]; |
| 2666 | int e, ee, c; |
| 2667 | |
| 2668 | e = (yo < xo && yo < 3-xo ? TE : |
| 2669 | yo > xo && yo > 3-xo ? BE : |
| 2670 | xo < 2 ? LE : RE); |
| 2671 | ee = map->map[e * wh + y*w+x]; |
| 2672 | |
| 2673 | if (xo != (yo * 2 + 1) % 5) |
| 2674 | continue; |
| 2675 | c = yo; |
| 2676 | |
| 2677 | if (!(pencil & ((ee == te ? PENCIL_T_BASE : PENCIL_B_BASE) << c))) |
| 2678 | continue; |
| 2679 | |
| 2680 | if (yo == xo && |
| 2681 | (map->map[TE * wh + y*w+x] != map->map[LE * wh + y*w+x])) |
| 2682 | continue; /* avoid TL-BR diagonal line */ |
| 2683 | if (yo == 3-xo && |
| 2684 | (map->map[TE * wh + y*w+x] != map->map[RE * wh + y*w+x])) |
| 2685 | continue; /* avoid BL-TR diagonal line */ |
| 2686 | |
| 2687 | draw_circle(dr, COORD(x) + (xo+1)*TILESIZE/5, |
| 2688 | COORD(y) + (yo+1)*TILESIZE/5, |
| 2689 | TILESIZE/7, COL_0 + c, COL_0 + c); |
| 2690 | } |
| 2691 | |
| 2692 | /* |
| 2693 | * Draw the grid lines, if required. |
| 2694 | */ |
| 2695 | if (x <= 0 || map->map[RE*wh+y*w+(x-1)] != map->map[LE*wh+y*w+x]) |
| 2696 | draw_rect(dr, COORD(x), COORD(y), 1, TILESIZE, COL_GRID); |
| 2697 | if (y <= 0 || map->map[BE*wh+(y-1)*w+x] != map->map[TE*wh+y*w+x]) |
| 2698 | draw_rect(dr, COORD(x), COORD(y), TILESIZE, 1, COL_GRID); |
| 2699 | if (x <= 0 || y <= 0 || |
| 2700 | map->map[RE*wh+(y-1)*w+(x-1)] != map->map[TE*wh+y*w+x] || |
| 2701 | map->map[BE*wh+(y-1)*w+(x-1)] != map->map[LE*wh+y*w+x]) |
| 2702 | draw_rect(dr, COORD(x), COORD(y), 1, 1, COL_GRID); |
| 2703 | |
| 2704 | /* |
| 2705 | * Draw error markers. |
| 2706 | */ |
| 2707 | for (yo = 0; yo < 3; yo++) |
| 2708 | for (xo = 0; xo < 3; xo++) |
| 2709 | if (errs & (ERR_BASE << (yo*3+xo))) |
| 2710 | draw_error(dr, ds, |
| 2711 | (COORD(x)*2+TILESIZE*xo)/2, |
| 2712 | (COORD(y)*2+TILESIZE*yo)/2); |
| 2713 | |
| 2714 | /* |
| 2715 | * Draw region numbers, if desired. |
| 2716 | */ |
| 2717 | if (show_numbers) { |
| 2718 | oldj = -1; |
| 2719 | for (i = 0; i < 2; i++) { |
| 2720 | j = map->map[(i?BE:TE)*wh+y*w+x]; |
| 2721 | if (oldj == j) |
| 2722 | continue; |
| 2723 | oldj = j; |
| 2724 | |
| 2725 | xo = map->regionx[j] - 2*x; |
| 2726 | yo = map->regiony[j] - 2*y; |
| 2727 | if (xo >= 0 && xo <= 2 && yo >= 0 && yo <= 2) { |
| 2728 | char buf[80]; |
| 2729 | sprintf(buf, "%d", j); |
| 2730 | draw_text(dr, (COORD(x)*2+TILESIZE*xo)/2, |
| 2731 | (COORD(y)*2+TILESIZE*yo)/2, |
| 2732 | FONT_VARIABLE, 3*TILESIZE/5, |
| 2733 | ALIGN_HCENTRE|ALIGN_VCENTRE, |
| 2734 | COL_GRID, buf); |
| 2735 | } |
| 2736 | } |
| 2737 | } |
| 2738 | |
| 2739 | unclip(dr); |
| 2740 | |
| 2741 | draw_update(dr, COORD(x), COORD(y), TILESIZE, TILESIZE); |
| 2742 | } |
| 2743 | |
| 2744 | static void game_redraw(drawing *dr, game_drawstate *ds, game_state *oldstate, |
| 2745 | game_state *state, int dir, game_ui *ui, |
| 2746 | float animtime, float flashtime) |
| 2747 | { |
| 2748 | int w = state->p.w, h = state->p.h, wh = w*h, n = state->p.n; |
| 2749 | int x, y, i; |
| 2750 | int flash; |
| 2751 | |
| 2752 | if (ds->drag_visible) { |
| 2753 | blitter_load(dr, ds->bl, ds->dragx, ds->dragy); |
| 2754 | draw_update(dr, ds->dragx, ds->dragy, TILESIZE + 3, TILESIZE + 3); |
| 2755 | ds->drag_visible = FALSE; |
| 2756 | } |
| 2757 | |
| 2758 | /* |
| 2759 | * The initial contents of the window are not guaranteed and |
| 2760 | * can vary with front ends. To be on the safe side, all games |
| 2761 | * should start by drawing a big background-colour rectangle |
| 2762 | * covering the whole window. |
| 2763 | */ |
| 2764 | if (!ds->started) { |
| 2765 | int ww, wh; |
| 2766 | |
| 2767 | game_compute_size(&state->p, TILESIZE, &ww, &wh); |
| 2768 | draw_rect(dr, 0, 0, ww, wh, COL_BACKGROUND); |
| 2769 | draw_rect(dr, COORD(0), COORD(0), w*TILESIZE+1, h*TILESIZE+1, |
| 2770 | COL_GRID); |
| 2771 | |
| 2772 | draw_update(dr, 0, 0, ww, wh); |
| 2773 | ds->started = TRUE; |
| 2774 | } |
| 2775 | |
| 2776 | if (flashtime) { |
| 2777 | if (flash_type == 1) |
| 2778 | flash = (int)(flashtime * FOUR / flash_length); |
| 2779 | else |
| 2780 | flash = 1 + (int)(flashtime * THREE / flash_length); |
| 2781 | } else |
| 2782 | flash = -1; |
| 2783 | |
| 2784 | /* |
| 2785 | * Set up the `todraw' array. |
| 2786 | */ |
| 2787 | for (y = 0; y < h; y++) |
| 2788 | for (x = 0; x < w; x++) { |
| 2789 | int tv = state->colouring[state->map->map[TE * wh + y*w+x]]; |
| 2790 | int bv = state->colouring[state->map->map[BE * wh + y*w+x]]; |
| 2791 | unsigned long v; |
| 2792 | |
| 2793 | if (tv < 0) |
| 2794 | tv = FOUR; |
| 2795 | if (bv < 0) |
| 2796 | bv = FOUR; |
| 2797 | |
| 2798 | if (flash >= 0) { |
| 2799 | if (flash_type == 1) { |
| 2800 | if (tv == flash) |
| 2801 | tv = FOUR; |
| 2802 | if (bv == flash) |
| 2803 | bv = FOUR; |
| 2804 | } else if (flash_type == 2) { |
| 2805 | if (flash % 2) |
| 2806 | tv = bv = FOUR; |
| 2807 | } else { |
| 2808 | if (tv != FOUR) |
| 2809 | tv = (tv + flash) % FOUR; |
| 2810 | if (bv != FOUR) |
| 2811 | bv = (bv + flash) % FOUR; |
| 2812 | } |
| 2813 | } |
| 2814 | |
| 2815 | v = tv * FIVE + bv; |
| 2816 | |
| 2817 | /* |
| 2818 | * Add pencil marks. |
| 2819 | */ |
| 2820 | for (i = 0; i < FOUR; i++) { |
| 2821 | if (state->colouring[state->map->map[TE * wh + y*w+x]] < 0 && |
| 2822 | (state->pencil[state->map->map[TE * wh + y*w+x]] & (1<<i))) |
| 2823 | v |= PENCIL_T_BASE << i; |
| 2824 | if (state->colouring[state->map->map[BE * wh + y*w+x]] < 0 && |
| 2825 | (state->pencil[state->map->map[BE * wh + y*w+x]] & (1<<i))) |
| 2826 | v |= PENCIL_B_BASE << i; |
| 2827 | } |
| 2828 | |
| 2829 | if (ui->show_numbers) |
| 2830 | v |= SHOW_NUMBERS; |
| 2831 | |
| 2832 | ds->todraw[y*w+x] = v; |
| 2833 | } |
| 2834 | |
| 2835 | /* |
| 2836 | * Add error markers to the `todraw' array. |
| 2837 | */ |
| 2838 | for (i = 0; i < state->map->ngraph; i++) { |
| 2839 | int v1 = state->map->graph[i] / n; |
| 2840 | int v2 = state->map->graph[i] % n; |
| 2841 | int xo, yo; |
| 2842 | |
| 2843 | if (state->colouring[v1] < 0 || state->colouring[v2] < 0) |
| 2844 | continue; |
| 2845 | if (state->colouring[v1] != state->colouring[v2]) |
| 2846 | continue; |
| 2847 | |
| 2848 | x = state->map->edgex[i]; |
| 2849 | y = state->map->edgey[i]; |
| 2850 | |
| 2851 | xo = x % 2; x /= 2; |
| 2852 | yo = y % 2; y /= 2; |
| 2853 | |
| 2854 | ds->todraw[y*w+x] |= ERR_BASE << (yo*3+xo); |
| 2855 | if (xo == 0) { |
| 2856 | assert(x > 0); |
| 2857 | ds->todraw[y*w+(x-1)] |= ERR_BASE << (yo*3+2); |
| 2858 | } |
| 2859 | if (yo == 0) { |
| 2860 | assert(y > 0); |
| 2861 | ds->todraw[(y-1)*w+x] |= ERR_BASE << (2*3+xo); |
| 2862 | } |
| 2863 | if (xo == 0 && yo == 0) { |
| 2864 | assert(x > 0 && y > 0); |
| 2865 | ds->todraw[(y-1)*w+(x-1)] |= ERR_BASE << (2*3+2); |
| 2866 | } |
| 2867 | } |
| 2868 | |
| 2869 | /* |
| 2870 | * Now actually draw everything. |
| 2871 | */ |
| 2872 | for (y = 0; y < h; y++) |
| 2873 | for (x = 0; x < w; x++) { |
| 2874 | unsigned long v = ds->todraw[y*w+x]; |
| 2875 | if (ds->drawn[y*w+x] != v) { |
| 2876 | draw_square(dr, ds, &state->p, state->map, x, y, v); |
| 2877 | ds->drawn[y*w+x] = v; |
| 2878 | } |
| 2879 | } |
| 2880 | |
| 2881 | /* |
| 2882 | * Draw the dragged colour blob if any. |
| 2883 | */ |
| 2884 | if (ui->drag_colour > -2) { |
| 2885 | ds->dragx = ui->dragx - TILESIZE/2 - 2; |
| 2886 | ds->dragy = ui->dragy - TILESIZE/2 - 2; |
| 2887 | blitter_save(dr, ds->bl, ds->dragx, ds->dragy); |
| 2888 | draw_circle(dr, ui->dragx, ui->dragy, TILESIZE/2, |
| 2889 | (ui->drag_colour < 0 ? COL_BACKGROUND : |
| 2890 | COL_0 + ui->drag_colour), COL_GRID); |
| 2891 | for (i = 0; i < FOUR; i++) |
| 2892 | if (ui->drag_pencil & (1 << i)) |
| 2893 | draw_circle(dr, ui->dragx + ((i*4+2)%10-3) * TILESIZE/10, |
| 2894 | ui->dragy + (i*2-3) * TILESIZE/10, |
| 2895 | TILESIZE/8, COL_0 + i, COL_0 + i); |
| 2896 | draw_update(dr, ds->dragx, ds->dragy, TILESIZE + 3, TILESIZE + 3); |
| 2897 | ds->drag_visible = TRUE; |
| 2898 | } |
| 2899 | } |
| 2900 | |
| 2901 | static float game_anim_length(game_state *oldstate, game_state *newstate, |
| 2902 | int dir, game_ui *ui) |
| 2903 | { |
| 2904 | return 0.0F; |
| 2905 | } |
| 2906 | |
| 2907 | static float game_flash_length(game_state *oldstate, game_state *newstate, |
| 2908 | int dir, game_ui *ui) |
| 2909 | { |
| 2910 | if (!oldstate->completed && newstate->completed && |
| 2911 | !oldstate->cheated && !newstate->cheated) { |
| 2912 | if (flash_type < 0) { |
| 2913 | char *env = getenv("MAP_ALTERNATIVE_FLASH"); |
| 2914 | if (env) |
| 2915 | flash_type = atoi(env); |
| 2916 | else |
| 2917 | flash_type = 0; |
| 2918 | flash_length = (flash_type == 1 ? 0.50 : 0.30); |
| 2919 | } |
| 2920 | return flash_length; |
| 2921 | } else |
| 2922 | return 0.0F; |
| 2923 | } |
| 2924 | |
| 2925 | static int game_timing_state(game_state *state, game_ui *ui) |
| 2926 | { |
| 2927 | return TRUE; |
| 2928 | } |
| 2929 | |
| 2930 | static void game_print_size(game_params *params, float *x, float *y) |
| 2931 | { |
| 2932 | int pw, ph; |
| 2933 | |
| 2934 | /* |
| 2935 | * I'll use 4mm squares by default, I think. Simplest way to |
| 2936 | * compute this size is to compute the pixel puzzle size at a |
| 2937 | * given tile size and then scale. |
| 2938 | */ |
| 2939 | game_compute_size(params, 400, &pw, &ph); |
| 2940 | *x = pw / 100.0; |
| 2941 | *y = ph / 100.0; |
| 2942 | } |
| 2943 | |
| 2944 | static void game_print(drawing *dr, game_state *state, int tilesize) |
| 2945 | { |
| 2946 | int w = state->p.w, h = state->p.h, wh = w*h, n = state->p.n; |
| 2947 | int ink, c[FOUR], i; |
| 2948 | int x, y, r; |
| 2949 | int *coords, ncoords, coordsize; |
| 2950 | |
| 2951 | /* Ick: fake up `ds->tilesize' for macro expansion purposes */ |
| 2952 | struct { int tilesize; } ads, *ds = &ads; |
| 2953 | /* We can't call game_set_size() here because we don't want a blitter */ |
| 2954 | ads.tilesize = tilesize; |
| 2955 | |
| 2956 | ink = print_mono_colour(dr, 0); |
| 2957 | for (i = 0; i < FOUR; i++) |
| 2958 | c[i] = print_rgb_colour(dr, map_hatching[i], map_colours[i][0], |
| 2959 | map_colours[i][1], map_colours[i][2]); |
| 2960 | |
| 2961 | coordsize = 0; |
| 2962 | coords = NULL; |
| 2963 | |
| 2964 | print_line_width(dr, TILESIZE / 16); |
| 2965 | |
| 2966 | /* |
| 2967 | * Draw a single filled polygon around each region. |
| 2968 | */ |
| 2969 | for (r = 0; r < n; r++) { |
| 2970 | int octants[8], lastdir, d1, d2, ox, oy; |
| 2971 | |
| 2972 | /* |
| 2973 | * Start by finding a point on the region boundary. Any |
| 2974 | * point will do. To do this, we'll search for a square |
| 2975 | * containing the region and then decide which corner of it |
| 2976 | * to use. |
| 2977 | */ |
| 2978 | x = w; |
| 2979 | for (y = 0; y < h; y++) { |
| 2980 | for (x = 0; x < w; x++) { |
| 2981 | if (state->map->map[wh*0+y*w+x] == r || |
| 2982 | state->map->map[wh*1+y*w+x] == r || |
| 2983 | state->map->map[wh*2+y*w+x] == r || |
| 2984 | state->map->map[wh*3+y*w+x] == r) |
| 2985 | break; |
| 2986 | } |
| 2987 | if (x < w) |
| 2988 | break; |
| 2989 | } |
| 2990 | assert(y < h && x < w); /* we must have found one somewhere */ |
| 2991 | /* |
| 2992 | * This is the first square in lexicographic order which |
| 2993 | * contains part of this region. Therefore, one of the top |
| 2994 | * two corners of the square must be what we're after. The |
| 2995 | * only case in which it isn't the top left one is if the |
| 2996 | * square is diagonally divided and the region is in the |
| 2997 | * bottom right half. |
| 2998 | */ |
| 2999 | if (state->map->map[wh*TE+y*w+x] != r && |
| 3000 | state->map->map[wh*LE+y*w+x] != r) |
| 3001 | x++; /* could just as well have done y++ */ |
| 3002 | |
| 3003 | /* |
| 3004 | * Now we have a point on the region boundary. Trace around |
| 3005 | * the region until we come back to this point, |
| 3006 | * accumulating coordinates for a polygon draw operation as |
| 3007 | * we go. |
| 3008 | */ |
| 3009 | lastdir = -1; |
| 3010 | ox = x; |
| 3011 | oy = y; |
| 3012 | ncoords = 0; |
| 3013 | |
| 3014 | do { |
| 3015 | /* |
| 3016 | * There are eight possible directions we could head in |
| 3017 | * from here. We identify them by octant numbers, and |
| 3018 | * we also use octant numbers to identify the spaces |
| 3019 | * between them: |
| 3020 | * |
| 3021 | * 6 7 0 |
| 3022 | * \ 7|0 / |
| 3023 | * \ | / |
| 3024 | * 6 \|/ 1 |
| 3025 | * 5-----+-----1 |
| 3026 | * 5 /|\ 2 |
| 3027 | * / | \ |
| 3028 | * / 4|3 \ |
| 3029 | * 4 3 2 |
| 3030 | */ |
| 3031 | octants[0] = x<w && y>0 ? state->map->map[wh*LE+(y-1)*w+x] : -1; |
| 3032 | octants[1] = x<w && y>0 ? state->map->map[wh*BE+(y-1)*w+x] : -1; |
| 3033 | octants[2] = x<w && y<h ? state->map->map[wh*TE+y*w+x] : -1; |
| 3034 | octants[3] = x<w && y<h ? state->map->map[wh*LE+y*w+x] : -1; |
| 3035 | octants[4] = x>0 && y<h ? state->map->map[wh*RE+y*w+(x-1)] : -1; |
| 3036 | octants[5] = x>0 && y<h ? state->map->map[wh*TE+y*w+(x-1)] : -1; |
| 3037 | octants[6] = x>0 && y>0 ? state->map->map[wh*BE+(y-1)*w+(x-1)] :-1; |
| 3038 | octants[7] = x>0 && y>0 ? state->map->map[wh*RE+(y-1)*w+(x-1)] :-1; |
| 3039 | |
| 3040 | d1 = d2 = -1; |
| 3041 | for (i = 0; i < 8; i++) |
| 3042 | if ((octants[i] == r) ^ (octants[(i+1)%8] == r)) { |
| 3043 | assert(d2 == -1); |
| 3044 | if (d1 == -1) |
| 3045 | d1 = i; |
| 3046 | else |
| 3047 | d2 = i; |
| 3048 | } |
| 3049 | |
| 3050 | assert(d1 != -1 && d2 != -1); |
| 3051 | if (d1 == lastdir) |
| 3052 | d1 = d2; |
| 3053 | |
| 3054 | /* |
| 3055 | * Now we're heading in direction d1. Save the current |
| 3056 | * coordinates. |
| 3057 | */ |
| 3058 | if (ncoords + 2 > coordsize) { |
| 3059 | coordsize += 128; |
| 3060 | coords = sresize(coords, coordsize, int); |
| 3061 | } |
| 3062 | coords[ncoords++] = COORD(x); |
| 3063 | coords[ncoords++] = COORD(y); |
| 3064 | |
| 3065 | /* |
| 3066 | * Compute the new coordinates. |
| 3067 | */ |
| 3068 | x += (d1 % 4 == 3 ? 0 : d1 < 4 ? +1 : -1); |
| 3069 | y += (d1 % 4 == 1 ? 0 : d1 > 1 && d1 < 5 ? +1 : -1); |
| 3070 | assert(x >= 0 && x <= w && y >= 0 && y <= h); |
| 3071 | |
| 3072 | lastdir = d1 ^ 4; |
| 3073 | } while (x != ox || y != oy); |
| 3074 | |
| 3075 | draw_polygon(dr, coords, ncoords/2, |
| 3076 | state->colouring[r] >= 0 ? |
| 3077 | c[state->colouring[r]] : -1, ink); |
| 3078 | } |
| 3079 | sfree(coords); |
| 3080 | } |
| 3081 | |
| 3082 | #ifdef COMBINED |
| 3083 | #define thegame map |
| 3084 | #endif |
| 3085 | |
| 3086 | const struct game thegame = { |
| 3087 | "Map", "games.map", "map", |
| 3088 | default_params, |
| 3089 | game_fetch_preset, |
| 3090 | decode_params, |
| 3091 | encode_params, |
| 3092 | free_params, |
| 3093 | dup_params, |
| 3094 | TRUE, game_configure, custom_params, |
| 3095 | validate_params, |
| 3096 | new_game_desc, |
| 3097 | validate_desc, |
| 3098 | new_game, |
| 3099 | dup_game, |
| 3100 | free_game, |
| 3101 | TRUE, solve_game, |
| 3102 | FALSE, game_text_format, |
| 3103 | new_ui, |
| 3104 | free_ui, |
| 3105 | encode_ui, |
| 3106 | decode_ui, |
| 3107 | game_changed_state, |
| 3108 | interpret_move, |
| 3109 | execute_move, |
| 3110 | 20, game_compute_size, game_set_size, |
| 3111 | game_colours, |
| 3112 | game_new_drawstate, |
| 3113 | game_free_drawstate, |
| 3114 | game_redraw, |
| 3115 | game_anim_length, |
| 3116 | game_flash_length, |
| 3117 | TRUE, TRUE, game_print_size, game_print, |
| 3118 | FALSE, /* wants_statusbar */ |
| 3119 | FALSE, game_timing_state, |
| 3120 | 0, /* flags */ |
| 3121 | }; |
| 3122 | |
| 3123 | #ifdef STANDALONE_SOLVER |
| 3124 | |
| 3125 | int main(int argc, char **argv) |
| 3126 | { |
| 3127 | game_params *p; |
| 3128 | game_state *s; |
| 3129 | char *id = NULL, *desc, *err; |
| 3130 | int grade = FALSE; |
| 3131 | int ret, diff, really_verbose = FALSE; |
| 3132 | struct solver_scratch *sc; |
| 3133 | int i; |
| 3134 | |
| 3135 | while (--argc > 0) { |
| 3136 | char *p = *++argv; |
| 3137 | if (!strcmp(p, "-v")) { |
| 3138 | really_verbose = TRUE; |
| 3139 | } else if (!strcmp(p, "-g")) { |
| 3140 | grade = TRUE; |
| 3141 | } else if (*p == '-') { |
| 3142 | fprintf(stderr, "%s: unrecognised option `%s'\n", argv[0], p); |
| 3143 | return 1; |
| 3144 | } else { |
| 3145 | id = p; |
| 3146 | } |
| 3147 | } |
| 3148 | |
| 3149 | if (!id) { |
| 3150 | fprintf(stderr, "usage: %s [-g | -v] <game_id>\n", argv[0]); |
| 3151 | return 1; |
| 3152 | } |
| 3153 | |
| 3154 | desc = strchr(id, ':'); |
| 3155 | if (!desc) { |
| 3156 | fprintf(stderr, "%s: game id expects a colon in it\n", argv[0]); |
| 3157 | return 1; |
| 3158 | } |
| 3159 | *desc++ = '\0'; |
| 3160 | |
| 3161 | p = default_params(); |
| 3162 | decode_params(p, id); |
| 3163 | err = validate_desc(p, desc); |
| 3164 | if (err) { |
| 3165 | fprintf(stderr, "%s: %s\n", argv[0], err); |
| 3166 | return 1; |
| 3167 | } |
| 3168 | s = new_game(NULL, p, desc); |
| 3169 | |
| 3170 | sc = new_scratch(s->map->graph, s->map->n, s->map->ngraph); |
| 3171 | |
| 3172 | /* |
| 3173 | * When solving an Easy puzzle, we don't want to bother the |
| 3174 | * user with Hard-level deductions. For this reason, we grade |
| 3175 | * the puzzle internally before doing anything else. |
| 3176 | */ |
| 3177 | ret = -1; /* placate optimiser */ |
| 3178 | for (diff = 0; diff < DIFFCOUNT; diff++) { |
| 3179 | for (i = 0; i < s->map->n; i++) |
| 3180 | if (!s->map->immutable[i]) |
| 3181 | s->colouring[i] = -1; |
| 3182 | ret = map_solver(sc, s->map->graph, s->map->n, s->map->ngraph, |
| 3183 | s->colouring, diff); |
| 3184 | if (ret < 2) |
| 3185 | break; |
| 3186 | } |
| 3187 | |
| 3188 | if (diff == DIFFCOUNT) { |
| 3189 | if (grade) |
| 3190 | printf("Difficulty rating: harder than Hard, or ambiguous\n"); |
| 3191 | else |
| 3192 | printf("Unable to find a unique solution\n"); |
| 3193 | } else { |
| 3194 | if (grade) { |
| 3195 | if (ret == 0) |
| 3196 | printf("Difficulty rating: impossible (no solution exists)\n"); |
| 3197 | else if (ret == 1) |
| 3198 | printf("Difficulty rating: %s\n", map_diffnames[diff]); |
| 3199 | } else { |
| 3200 | verbose = really_verbose; |
| 3201 | for (i = 0; i < s->map->n; i++) |
| 3202 | if (!s->map->immutable[i]) |
| 3203 | s->colouring[i] = -1; |
| 3204 | ret = map_solver(sc, s->map->graph, s->map->n, s->map->ngraph, |
| 3205 | s->colouring, diff); |
| 3206 | if (ret == 0) |
| 3207 | printf("Puzzle is inconsistent\n"); |
| 3208 | else { |
| 3209 | int col = 0; |
| 3210 | |
| 3211 | for (i = 0; i < s->map->n; i++) { |
| 3212 | printf("%5d <- %c%c", i, colnames[s->colouring[i]], |
| 3213 | (col < 6 && i+1 < s->map->n ? ' ' : '\n')); |
| 3214 | if (++col == 7) |
| 3215 | col = 0; |
| 3216 | } |
| 3217 | } |
| 3218 | } |
| 3219 | } |
| 3220 | |
| 3221 | return 0; |
| 3222 | } |
| 3223 | |
| 3224 | #endif |