| 1 | /* |
| 2 | * net.c: Net game. |
| 3 | */ |
| 4 | |
| 5 | #include <stdio.h> |
| 6 | #include <stdlib.h> |
| 7 | #include <string.h> |
| 8 | #include <assert.h> |
| 9 | #include <ctype.h> |
| 10 | #include <math.h> |
| 11 | |
| 12 | #include "puzzles.h" |
| 13 | #include "tree234.h" |
| 14 | |
| 15 | /* |
| 16 | * The standard user interface for Net simply has left- and |
| 17 | * right-button mouse clicks in a square rotate it one way or the |
| 18 | * other. We also provide, by #ifdef, a separate interface based on |
| 19 | * rotational dragging motions. I initially developed this for the |
| 20 | * Mac on the basis that it might work better than the click |
| 21 | * interface with only one mouse button available, but in fact |
| 22 | * found it to be quite strange and unintuitive. Apparently it |
| 23 | * works better on stylus-driven platforms such as Palm and |
| 24 | * PocketPC, though, so we enable it by default there. |
| 25 | */ |
| 26 | #ifdef STYLUS_BASED |
| 27 | #define USE_DRAGGING |
| 28 | #endif |
| 29 | |
| 30 | #define MATMUL(xr,yr,m,x,y) do { \ |
| 31 | float rx, ry, xx = (x), yy = (y), *mat = (m); \ |
| 32 | rx = mat[0] * xx + mat[2] * yy; \ |
| 33 | ry = mat[1] * xx + mat[3] * yy; \ |
| 34 | (xr) = rx; (yr) = ry; \ |
| 35 | } while (0) |
| 36 | |
| 37 | /* Direction and other bitfields */ |
| 38 | #define R 0x01 |
| 39 | #define U 0x02 |
| 40 | #define L 0x04 |
| 41 | #define D 0x08 |
| 42 | #define LOCKED 0x10 |
| 43 | #define ACTIVE 0x20 |
| 44 | |
| 45 | /* Rotations: Anticlockwise, Clockwise, Flip, general rotate */ |
| 46 | #define A(x) ( (((x) & 0x07) << 1) | (((x) & 0x08) >> 3) ) |
| 47 | #define C(x) ( (((x) & 0x0E) >> 1) | (((x) & 0x01) << 3) ) |
| 48 | #define F(x) ( (((x) & 0x0C) >> 2) | (((x) & 0x03) << 2) ) |
| 49 | #define ROT(x, n) ( ((n)&3) == 0 ? (x) : \ |
| 50 | ((n)&3) == 1 ? A(x) : \ |
| 51 | ((n)&3) == 2 ? F(x) : C(x) ) |
| 52 | |
| 53 | /* X and Y displacements */ |
| 54 | #define X(x) ( (x) == R ? +1 : (x) == L ? -1 : 0 ) |
| 55 | #define Y(x) ( (x) == D ? +1 : (x) == U ? -1 : 0 ) |
| 56 | |
| 57 | /* Bit count */ |
| 58 | #define COUNT(x) ( (((x) & 0x08) >> 3) + (((x) & 0x04) >> 2) + \ |
| 59 | (((x) & 0x02) >> 1) + ((x) & 0x01) ) |
| 60 | |
| 61 | #define PREFERRED_TILE_SIZE 32 |
| 62 | #define TILE_SIZE (ds->tilesize) |
| 63 | #define TILE_BORDER 1 |
| 64 | #ifdef SMALL_SCREEN |
| 65 | #define WINDOW_OFFSET 4 |
| 66 | #else |
| 67 | #define WINDOW_OFFSET 16 |
| 68 | #endif |
| 69 | |
| 70 | #define ROTATE_TIME 0.13F |
| 71 | #define FLASH_FRAME 0.07F |
| 72 | |
| 73 | /* Transform physical coords to game coords using game_drawstate ds */ |
| 74 | #define GX(x) (((x) + ds->org_x) % ds->width) |
| 75 | #define GY(y) (((y) + ds->org_y) % ds->height) |
| 76 | /* ...and game coords to physical coords */ |
| 77 | #define RX(x) (((x) + ds->width - ds->org_x) % ds->width) |
| 78 | #define RY(y) (((y) + ds->height - ds->org_y) % ds->height) |
| 79 | |
| 80 | enum { |
| 81 | COL_BACKGROUND, |
| 82 | COL_LOCKED, |
| 83 | COL_BORDER, |
| 84 | COL_WIRE, |
| 85 | COL_ENDPOINT, |
| 86 | COL_POWERED, |
| 87 | COL_BARRIER, |
| 88 | NCOLOURS |
| 89 | }; |
| 90 | |
| 91 | struct game_params { |
| 92 | int width; |
| 93 | int height; |
| 94 | int wrapping; |
| 95 | int unique; |
| 96 | float barrier_probability; |
| 97 | }; |
| 98 | |
| 99 | struct game_state { |
| 100 | int width, height, wrapping, completed; |
| 101 | int last_rotate_x, last_rotate_y, last_rotate_dir; |
| 102 | int used_solve; |
| 103 | unsigned char *tiles; |
| 104 | unsigned char *barriers; |
| 105 | }; |
| 106 | |
| 107 | #define OFFSETWH(x2,y2,x1,y1,dir,width,height) \ |
| 108 | ( (x2) = ((x1) + width + X((dir))) % width, \ |
| 109 | (y2) = ((y1) + height + Y((dir))) % height) |
| 110 | |
| 111 | #define OFFSET(x2,y2,x1,y1,dir,state) \ |
| 112 | OFFSETWH(x2,y2,x1,y1,dir,(state)->width,(state)->height) |
| 113 | |
| 114 | #define index(state, a, x, y) ( a[(y) * (state)->width + (x)] ) |
| 115 | #define tile(state, x, y) index(state, (state)->tiles, x, y) |
| 116 | #define barrier(state, x, y) index(state, (state)->barriers, x, y) |
| 117 | |
| 118 | struct xyd { |
| 119 | int x, y, direction; |
| 120 | }; |
| 121 | |
| 122 | static int xyd_cmp(const void *av, const void *bv) { |
| 123 | const struct xyd *a = (const struct xyd *)av; |
| 124 | const struct xyd *b = (const struct xyd *)bv; |
| 125 | if (a->x < b->x) |
| 126 | return -1; |
| 127 | if (a->x > b->x) |
| 128 | return +1; |
| 129 | if (a->y < b->y) |
| 130 | return -1; |
| 131 | if (a->y > b->y) |
| 132 | return +1; |
| 133 | if (a->direction < b->direction) |
| 134 | return -1; |
| 135 | if (a->direction > b->direction) |
| 136 | return +1; |
| 137 | return 0; |
| 138 | } |
| 139 | |
| 140 | static int xyd_cmp_nc(void *av, void *bv) { return xyd_cmp(av, bv); } |
| 141 | |
| 142 | static struct xyd *new_xyd(int x, int y, int direction) |
| 143 | { |
| 144 | struct xyd *xyd = snew(struct xyd); |
| 145 | xyd->x = x; |
| 146 | xyd->y = y; |
| 147 | xyd->direction = direction; |
| 148 | return xyd; |
| 149 | } |
| 150 | |
| 151 | /* ---------------------------------------------------------------------- |
| 152 | * Manage game parameters. |
| 153 | */ |
| 154 | static game_params *default_params(void) |
| 155 | { |
| 156 | game_params *ret = snew(game_params); |
| 157 | |
| 158 | ret->width = 5; |
| 159 | ret->height = 5; |
| 160 | ret->wrapping = FALSE; |
| 161 | ret->unique = TRUE; |
| 162 | ret->barrier_probability = 0.0; |
| 163 | |
| 164 | return ret; |
| 165 | } |
| 166 | |
| 167 | static const struct game_params net_presets[] = { |
| 168 | {5, 5, FALSE, TRUE, 0.0}, |
| 169 | {7, 7, FALSE, TRUE, 0.0}, |
| 170 | {9, 9, FALSE, TRUE, 0.0}, |
| 171 | {11, 11, FALSE, TRUE, 0.0}, |
| 172 | #ifndef SMALL_SCREEN |
| 173 | {13, 11, FALSE, TRUE, 0.0}, |
| 174 | #endif |
| 175 | {5, 5, TRUE, TRUE, 0.0}, |
| 176 | {7, 7, TRUE, TRUE, 0.0}, |
| 177 | {9, 9, TRUE, TRUE, 0.0}, |
| 178 | {11, 11, TRUE, TRUE, 0.0}, |
| 179 | #ifndef SMALL_SCREEN |
| 180 | {13, 11, TRUE, TRUE, 0.0}, |
| 181 | #endif |
| 182 | }; |
| 183 | |
| 184 | static int game_fetch_preset(int i, char **name, game_params **params) |
| 185 | { |
| 186 | game_params *ret; |
| 187 | char str[80]; |
| 188 | |
| 189 | if (i < 0 || i >= lenof(net_presets)) |
| 190 | return FALSE; |
| 191 | |
| 192 | ret = snew(game_params); |
| 193 | *ret = net_presets[i]; |
| 194 | |
| 195 | sprintf(str, "%dx%d%s", ret->width, ret->height, |
| 196 | ret->wrapping ? " wrapping" : ""); |
| 197 | |
| 198 | *name = dupstr(str); |
| 199 | *params = ret; |
| 200 | return TRUE; |
| 201 | } |
| 202 | |
| 203 | static void free_params(game_params *params) |
| 204 | { |
| 205 | sfree(params); |
| 206 | } |
| 207 | |
| 208 | static game_params *dup_params(game_params *params) |
| 209 | { |
| 210 | game_params *ret = snew(game_params); |
| 211 | *ret = *params; /* structure copy */ |
| 212 | return ret; |
| 213 | } |
| 214 | |
| 215 | static void decode_params(game_params *ret, char const *string) |
| 216 | { |
| 217 | char const *p = string; |
| 218 | |
| 219 | ret->width = atoi(p); |
| 220 | while (*p && isdigit((unsigned char)*p)) p++; |
| 221 | if (*p == 'x') { |
| 222 | p++; |
| 223 | ret->height = atoi(p); |
| 224 | while (*p && isdigit((unsigned char)*p)) p++; |
| 225 | } else { |
| 226 | ret->height = ret->width; |
| 227 | } |
| 228 | |
| 229 | while (*p) { |
| 230 | if (*p == 'w') { |
| 231 | p++; |
| 232 | ret->wrapping = TRUE; |
| 233 | } else if (*p == 'b') { |
| 234 | p++; |
| 235 | ret->barrier_probability = (float)atof(p); |
| 236 | while (*p && (*p == '.' || isdigit((unsigned char)*p))) p++; |
| 237 | } else if (*p == 'a') { |
| 238 | p++; |
| 239 | ret->unique = FALSE; |
| 240 | } else |
| 241 | p++; /* skip any other gunk */ |
| 242 | } |
| 243 | } |
| 244 | |
| 245 | static char *encode_params(game_params *params, int full) |
| 246 | { |
| 247 | char ret[400]; |
| 248 | int len; |
| 249 | |
| 250 | len = sprintf(ret, "%dx%d", params->width, params->height); |
| 251 | if (params->wrapping) |
| 252 | ret[len++] = 'w'; |
| 253 | if (full && params->barrier_probability) |
| 254 | len += sprintf(ret+len, "b%g", params->barrier_probability); |
| 255 | if (full && !params->unique) |
| 256 | ret[len++] = 'a'; |
| 257 | assert(len < lenof(ret)); |
| 258 | ret[len] = '\0'; |
| 259 | |
| 260 | return dupstr(ret); |
| 261 | } |
| 262 | |
| 263 | static config_item *game_configure(game_params *params) |
| 264 | { |
| 265 | config_item *ret; |
| 266 | char buf[80]; |
| 267 | |
| 268 | ret = snewn(6, config_item); |
| 269 | |
| 270 | ret[0].name = "Width"; |
| 271 | ret[0].type = C_STRING; |
| 272 | sprintf(buf, "%d", params->width); |
| 273 | ret[0].sval = dupstr(buf); |
| 274 | ret[0].ival = 0; |
| 275 | |
| 276 | ret[1].name = "Height"; |
| 277 | ret[1].type = C_STRING; |
| 278 | sprintf(buf, "%d", params->height); |
| 279 | ret[1].sval = dupstr(buf); |
| 280 | ret[1].ival = 0; |
| 281 | |
| 282 | ret[2].name = "Walls wrap around"; |
| 283 | ret[2].type = C_BOOLEAN; |
| 284 | ret[2].sval = NULL; |
| 285 | ret[2].ival = params->wrapping; |
| 286 | |
| 287 | ret[3].name = "Barrier probability"; |
| 288 | ret[3].type = C_STRING; |
| 289 | sprintf(buf, "%g", params->barrier_probability); |
| 290 | ret[3].sval = dupstr(buf); |
| 291 | ret[3].ival = 0; |
| 292 | |
| 293 | ret[4].name = "Ensure unique solution"; |
| 294 | ret[4].type = C_BOOLEAN; |
| 295 | ret[4].sval = NULL; |
| 296 | ret[4].ival = params->unique; |
| 297 | |
| 298 | ret[5].name = NULL; |
| 299 | ret[5].type = C_END; |
| 300 | ret[5].sval = NULL; |
| 301 | ret[5].ival = 0; |
| 302 | |
| 303 | return ret; |
| 304 | } |
| 305 | |
| 306 | static game_params *custom_params(config_item *cfg) |
| 307 | { |
| 308 | game_params *ret = snew(game_params); |
| 309 | |
| 310 | ret->width = atoi(cfg[0].sval); |
| 311 | ret->height = atoi(cfg[1].sval); |
| 312 | ret->wrapping = cfg[2].ival; |
| 313 | ret->barrier_probability = (float)atof(cfg[3].sval); |
| 314 | ret->unique = cfg[4].ival; |
| 315 | |
| 316 | return ret; |
| 317 | } |
| 318 | |
| 319 | static char *validate_params(game_params *params, int full) |
| 320 | { |
| 321 | if (params->width <= 0 || params->height <= 0) |
| 322 | return "Width and height must both be greater than zero"; |
| 323 | if (params->width <= 1 && params->height <= 1) |
| 324 | return "At least one of width and height must be greater than one"; |
| 325 | if (params->barrier_probability < 0) |
| 326 | return "Barrier probability may not be negative"; |
| 327 | if (params->barrier_probability > 1) |
| 328 | return "Barrier probability may not be greater than 1"; |
| 329 | |
| 330 | /* |
| 331 | * Specifying either grid dimension as 2 in a wrapping puzzle |
| 332 | * makes it actually impossible to ensure a unique puzzle |
| 333 | * solution. |
| 334 | * |
| 335 | * Proof: |
| 336 | * |
| 337 | * Without loss of generality, let us assume the puzzle _width_ |
| 338 | * is 2, so we can conveniently discuss rows without having to |
| 339 | * say `rows/columns' all the time. (The height may be 2 as |
| 340 | * well, but that doesn't matter.) |
| 341 | * |
| 342 | * In each row, there are two edges between tiles: the inner |
| 343 | * edge (running down the centre of the grid) and the outer |
| 344 | * edge (the identified left and right edges of the grid). |
| 345 | * |
| 346 | * Lemma: In any valid 2xn puzzle there must be at least one |
| 347 | * row in which _exactly one_ of the inner edge and outer edge |
| 348 | * is connected. |
| 349 | * |
| 350 | * Proof: No row can have _both_ inner and outer edges |
| 351 | * connected, because this would yield a loop. So the only |
| 352 | * other way to falsify the lemma is for every row to have |
| 353 | * _neither_ the inner nor outer edge connected. But this |
| 354 | * means there is no connection at all between the left and |
| 355 | * right columns of the puzzle, so there are two disjoint |
| 356 | * subgraphs, which is also disallowed. [] |
| 357 | * |
| 358 | * Given such a row, it is always possible to make the |
| 359 | * disconnected edge connected and the connected edge |
| 360 | * disconnected without changing the state of any other edge. |
| 361 | * (This is easily seen by case analysis on the various tiles: |
| 362 | * left-pointing and right-pointing endpoints can be exchanged, |
| 363 | * likewise T-pieces, and a corner piece can select its |
| 364 | * horizontal connectivity independently of its vertical.) This |
| 365 | * yields a distinct valid solution. |
| 366 | * |
| 367 | * Thus, for _every_ row in which exactly one of the inner and |
| 368 | * outer edge is connected, there are two valid states for that |
| 369 | * row, and hence the total number of solutions of the puzzle |
| 370 | * is at least 2^(number of such rows), and in particular is at |
| 371 | * least 2 since there must be at least one such row. [] |
| 372 | */ |
| 373 | if (full && params->unique && params->wrapping && |
| 374 | (params->width == 2 || params->height == 2)) |
| 375 | return "No wrapping puzzle with a width or height of 2 can have" |
| 376 | " a unique solution"; |
| 377 | |
| 378 | return NULL; |
| 379 | } |
| 380 | |
| 381 | /* ---------------------------------------------------------------------- |
| 382 | * Solver used to assure solution uniqueness during generation. |
| 383 | */ |
| 384 | |
| 385 | /* |
| 386 | * Test cases I used while debugging all this were |
| 387 | * |
| 388 | * ./net --generate 1 13x11w#12300 |
| 389 | * which expands under the non-unique grid generation rules to |
| 390 | * 13x11w:5eaade1bd222664436d5e2965c12656b1129dd825219e3274d558d5eb2dab5da18898e571d5a2987be79746bd95726c597447d6da96188c513add829da7681da954db113d3cd244 |
| 391 | * and has two ambiguous areas. |
| 392 | * |
| 393 | * An even better one is |
| 394 | * 13x11w#507896411361192 |
| 395 | * which expands to |
| 396 | * 13x11w:b7125b1aec598eb31bd58d82572bc11494e5dee4e8db2bdd29b88d41a16bdd996d2996ddec8c83741a1e8674e78328ba71737b8894a9271b1cd1399453d1952e43951d9b712822e |
| 397 | * and has an ambiguous area _and_ a situation where loop avoidance |
| 398 | * is a necessary deductive technique. |
| 399 | * |
| 400 | * Then there's |
| 401 | * 48x25w#820543338195187 |
| 402 | * becoming |
| 403 | * 48x25w:255989d14cdd185deaa753a93821a12edc1ab97943ac127e2685d7b8b3c48861b2192416139212b316eddd35de43714ebc7628d753db32e596284d9ec52c5a7dc1b4c811a655117d16dc28921b2b4161352cab1d89d18bc836b8b891d55ea4622a1251861b5bc9a8aa3e5bcd745c95229ca6c3b5e21d5832d397e917325793d7eb442dc351b2db2a52ba8e1651642275842d8871d5534aabc6d5b741aaa2d48ed2a7dbbb3151ddb49d5b9a7ed1ab98ee75d613d656dbba347bc514c84556b43a9bc65a3256ead792488b862a9d2a8a39b4255a4949ed7dbd79443292521265896b4399c95ede89d7c8c797a6a57791a849adea489359a158aa12e5dacce862b8333b7ebea7d344d1a3c53198864b73a9dedde7b663abb1b539e1e8853b1b7edb14a2a17ebaae4dbe63598a2e7e9a2dbdad415bc1d8cb88cbab5a8c82925732cd282e641ea3bd7d2c6e776de9117a26be86deb7c82c89524b122cb9397cd1acd2284e744ea62b9279bae85479ababe315c3ac29c431333395b24e6a1e3c43a2da42d4dce84aadd5b154aea555eaddcbd6e527d228c19388d9b424d94214555a7edbdeebe569d4a56dc51a86bd9963e377bb74752bd5eaa5761ba545e297b62a1bda46ab4aee423ad6c661311783cc18786d4289236563cb4a75ec67d481c14814994464cd1b87396dee63e5ab6e952cc584baa1d4c47cb557ec84dbb63d487c8728118673a166846dd3a4ebc23d6cb9c5827d96b4556e91899db32b517eda815ae271a8911bd745447121dc8d321557bc2a435ebec1bbac35b1a291669451174e6aa2218a4a9c5a6ca31ebc45d84e3a82c121e9ced7d55e9a |
| 404 | * which has a spot (far right) where slightly more complex loop |
| 405 | * avoidance is required. |
| 406 | */ |
| 407 | |
| 408 | struct todo { |
| 409 | unsigned char *marked; |
| 410 | int *buffer; |
| 411 | int buflen; |
| 412 | int head, tail; |
| 413 | }; |
| 414 | |
| 415 | static struct todo *todo_new(int maxsize) |
| 416 | { |
| 417 | struct todo *todo = snew(struct todo); |
| 418 | todo->marked = snewn(maxsize, unsigned char); |
| 419 | memset(todo->marked, 0, maxsize); |
| 420 | todo->buflen = maxsize + 1; |
| 421 | todo->buffer = snewn(todo->buflen, int); |
| 422 | todo->head = todo->tail = 0; |
| 423 | return todo; |
| 424 | } |
| 425 | |
| 426 | static void todo_free(struct todo *todo) |
| 427 | { |
| 428 | sfree(todo->marked); |
| 429 | sfree(todo->buffer); |
| 430 | sfree(todo); |
| 431 | } |
| 432 | |
| 433 | static void todo_add(struct todo *todo, int index) |
| 434 | { |
| 435 | if (todo->marked[index]) |
| 436 | return; /* already on the list */ |
| 437 | todo->marked[index] = TRUE; |
| 438 | todo->buffer[todo->tail++] = index; |
| 439 | if (todo->tail == todo->buflen) |
| 440 | todo->tail = 0; |
| 441 | } |
| 442 | |
| 443 | static int todo_get(struct todo *todo) { |
| 444 | int ret; |
| 445 | |
| 446 | if (todo->head == todo->tail) |
| 447 | return -1; /* list is empty */ |
| 448 | ret = todo->buffer[todo->head++]; |
| 449 | if (todo->head == todo->buflen) |
| 450 | todo->head = 0; |
| 451 | todo->marked[ret] = FALSE; |
| 452 | |
| 453 | return ret; |
| 454 | } |
| 455 | |
| 456 | static int net_solver(int w, int h, unsigned char *tiles, |
| 457 | unsigned char *barriers, int wrapping) |
| 458 | { |
| 459 | unsigned char *tilestate; |
| 460 | unsigned char *edgestate; |
| 461 | int *deadends; |
| 462 | int *equivalence; |
| 463 | struct todo *todo; |
| 464 | int i, j, x, y; |
| 465 | int area; |
| 466 | int done_something; |
| 467 | |
| 468 | /* |
| 469 | * Set up the solver's data structures. |
| 470 | */ |
| 471 | |
| 472 | /* |
| 473 | * tilestate stores the possible orientations of each tile. |
| 474 | * There are up to four of these, so we'll index the array in |
| 475 | * fours. tilestate[(y * w + x) * 4] and its three successive |
| 476 | * members give the possible orientations, clearing to 255 from |
| 477 | * the end as things are ruled out. |
| 478 | * |
| 479 | * In this loop we also count up the area of the grid (which is |
| 480 | * not _necessarily_ equal to w*h, because there might be one |
| 481 | * or more blank squares present. This will never happen in a |
| 482 | * grid generated _by_ this program, but it's worth keeping the |
| 483 | * solver as general as possible.) |
| 484 | */ |
| 485 | tilestate = snewn(w * h * 4, unsigned char); |
| 486 | area = 0; |
| 487 | for (i = 0; i < w*h; i++) { |
| 488 | tilestate[i * 4] = tiles[i] & 0xF; |
| 489 | for (j = 1; j < 4; j++) { |
| 490 | if (tilestate[i * 4 + j - 1] == 255 || |
| 491 | A(tilestate[i * 4 + j - 1]) == tilestate[i * 4]) |
| 492 | tilestate[i * 4 + j] = 255; |
| 493 | else |
| 494 | tilestate[i * 4 + j] = A(tilestate[i * 4 + j - 1]); |
| 495 | } |
| 496 | if (tiles[i] != 0) |
| 497 | area++; |
| 498 | } |
| 499 | |
| 500 | /* |
| 501 | * edgestate stores the known state of each edge. It is 0 for |
| 502 | * unknown, 1 for open (connected) and 2 for closed (not |
| 503 | * connected). |
| 504 | * |
| 505 | * In principle we need only worry about each edge once each, |
| 506 | * but in fact it's easier to track each edge twice so that we |
| 507 | * can reference it from either side conveniently. Also I'm |
| 508 | * going to allocate _five_ bytes per tile, rather than the |
| 509 | * obvious four, so that I can index edgestate[(y*w+x) * 5 + d] |
| 510 | * where d is 1,2,4,8 and they never overlap. |
| 511 | */ |
| 512 | edgestate = snewn((w * h - 1) * 5 + 9, unsigned char); |
| 513 | memset(edgestate, 0, (w * h - 1) * 5 + 9); |
| 514 | |
| 515 | /* |
| 516 | * deadends tracks which edges have dead ends on them. It is |
| 517 | * indexed by tile and direction: deadends[(y*w+x) * 5 + d] |
| 518 | * tells you whether heading out of tile (x,y) in direction d |
| 519 | * can reach a limited amount of the grid. Values are area+1 |
| 520 | * (no dead end known) or less than that (can reach _at most_ |
| 521 | * this many other tiles by heading this way out of this tile). |
| 522 | */ |
| 523 | deadends = snewn((w * h - 1) * 5 + 9, int); |
| 524 | for (i = 0; i < (w * h - 1) * 5 + 9; i++) |
| 525 | deadends[i] = area+1; |
| 526 | |
| 527 | /* |
| 528 | * equivalence tracks which sets of tiles are known to be |
| 529 | * connected to one another, so we can avoid creating loops by |
| 530 | * linking together tiles which are already linked through |
| 531 | * another route. |
| 532 | * |
| 533 | * This is a disjoint set forest structure: equivalence[i] |
| 534 | * contains the index of another member of the equivalence |
| 535 | * class containing i, or contains i itself for precisely one |
| 536 | * member in each such class. To find a representative member |
| 537 | * of the equivalence class containing i, you keep replacing i |
| 538 | * with equivalence[i] until it stops changing; then you go |
| 539 | * _back_ along the same path and point everything on it |
| 540 | * directly at the representative member so as to speed up |
| 541 | * future searches. Then you test equivalence between tiles by |
| 542 | * finding the representative of each tile and seeing if |
| 543 | * they're the same; and you create new equivalence (merge |
| 544 | * classes) by finding the representative of each tile and |
| 545 | * setting equivalence[one]=the_other. |
| 546 | */ |
| 547 | equivalence = snew_dsf(w * h); |
| 548 | |
| 549 | /* |
| 550 | * On a non-wrapping grid, we instantly know that all the edges |
| 551 | * round the edge are closed. |
| 552 | */ |
| 553 | if (!wrapping) { |
| 554 | for (i = 0; i < w; i++) { |
| 555 | edgestate[i * 5 + 2] = edgestate[((h-1) * w + i) * 5 + 8] = 2; |
| 556 | } |
| 557 | for (i = 0; i < h; i++) { |
| 558 | edgestate[(i * w + w-1) * 5 + 1] = edgestate[(i * w) * 5 + 4] = 2; |
| 559 | } |
| 560 | } |
| 561 | |
| 562 | /* |
| 563 | * If we have barriers available, we can mark those edges as |
| 564 | * closed too. |
| 565 | */ |
| 566 | if (barriers) { |
| 567 | for (y = 0; y < h; y++) for (x = 0; x < w; x++) { |
| 568 | int d; |
| 569 | for (d = 1; d <= 8; d += d) { |
| 570 | if (barriers[y*w+x] & d) { |
| 571 | int x2, y2; |
| 572 | /* |
| 573 | * In principle the barrier list should already |
| 574 | * contain each barrier from each side, but |
| 575 | * let's not take chances with our internal |
| 576 | * consistency. |
| 577 | */ |
| 578 | OFFSETWH(x2, y2, x, y, d, w, h); |
| 579 | edgestate[(y*w+x) * 5 + d] = 2; |
| 580 | edgestate[(y2*w+x2) * 5 + F(d)] = 2; |
| 581 | } |
| 582 | } |
| 583 | } |
| 584 | } |
| 585 | |
| 586 | /* |
| 587 | * Since most deductions made by this solver are local (the |
| 588 | * exception is loop avoidance, where joining two tiles |
| 589 | * together on one side of the grid can theoretically permit a |
| 590 | * fresh deduction on the other), we can address the scaling |
| 591 | * problem inherent in iterating repeatedly over the entire |
| 592 | * grid by instead working with a to-do list. |
| 593 | */ |
| 594 | todo = todo_new(w * h); |
| 595 | |
| 596 | /* |
| 597 | * Main deductive loop. |
| 598 | */ |
| 599 | done_something = TRUE; /* prevent instant termination! */ |
| 600 | while (1) { |
| 601 | int index; |
| 602 | |
| 603 | /* |
| 604 | * Take a tile index off the todo list and process it. |
| 605 | */ |
| 606 | index = todo_get(todo); |
| 607 | if (index == -1) { |
| 608 | /* |
| 609 | * If we have run out of immediate things to do, we |
| 610 | * have no choice but to scan the whole grid for |
| 611 | * longer-range things we've missed. Hence, I now add |
| 612 | * every square on the grid back on to the to-do list. |
| 613 | * I also set `done_something' to FALSE at this point; |
| 614 | * if we later come back here and find it still FALSE, |
| 615 | * we will know we've scanned the entire grid without |
| 616 | * finding anything new to do, and we can terminate. |
| 617 | */ |
| 618 | if (!done_something) |
| 619 | break; |
| 620 | for (i = 0; i < w*h; i++) |
| 621 | todo_add(todo, i); |
| 622 | done_something = FALSE; |
| 623 | |
| 624 | index = todo_get(todo); |
| 625 | } |
| 626 | |
| 627 | y = index / w; |
| 628 | x = index % w; |
| 629 | { |
| 630 | int d, ourclass = dsf_canonify(equivalence, y*w+x); |
| 631 | int deadendmax[9]; |
| 632 | |
| 633 | deadendmax[1] = deadendmax[2] = deadendmax[4] = deadendmax[8] = 0; |
| 634 | |
| 635 | for (i = j = 0; i < 4 && tilestate[(y*w+x) * 4 + i] != 255; i++) { |
| 636 | int valid; |
| 637 | int nnondeadends, nondeadends[4], deadendtotal; |
| 638 | int nequiv, equiv[5]; |
| 639 | int val = tilestate[(y*w+x) * 4 + i]; |
| 640 | |
| 641 | valid = TRUE; |
| 642 | nnondeadends = deadendtotal = 0; |
| 643 | equiv[0] = ourclass; |
| 644 | nequiv = 1; |
| 645 | for (d = 1; d <= 8; d += d) { |
| 646 | /* |
| 647 | * Immediately rule out this orientation if it |
| 648 | * conflicts with any known edge. |
| 649 | */ |
| 650 | if ((edgestate[(y*w+x) * 5 + d] == 1 && !(val & d)) || |
| 651 | (edgestate[(y*w+x) * 5 + d] == 2 && (val & d))) |
| 652 | valid = FALSE; |
| 653 | |
| 654 | if (val & d) { |
| 655 | /* |
| 656 | * Count up the dead-end statistics. |
| 657 | */ |
| 658 | if (deadends[(y*w+x) * 5 + d] <= area) { |
| 659 | deadendtotal += deadends[(y*w+x) * 5 + d]; |
| 660 | } else { |
| 661 | nondeadends[nnondeadends++] = d; |
| 662 | } |
| 663 | |
| 664 | /* |
| 665 | * Ensure we aren't linking to any tiles, |
| 666 | * through edges not already known to be |
| 667 | * open, which create a loop. |
| 668 | */ |
| 669 | if (edgestate[(y*w+x) * 5 + d] == 0) { |
| 670 | int c, k, x2, y2; |
| 671 | |
| 672 | OFFSETWH(x2, y2, x, y, d, w, h); |
| 673 | c = dsf_canonify(equivalence, y2*w+x2); |
| 674 | for (k = 0; k < nequiv; k++) |
| 675 | if (c == equiv[k]) |
| 676 | break; |
| 677 | if (k == nequiv) |
| 678 | equiv[nequiv++] = c; |
| 679 | else |
| 680 | valid = FALSE; |
| 681 | } |
| 682 | } |
| 683 | } |
| 684 | |
| 685 | if (nnondeadends == 0) { |
| 686 | /* |
| 687 | * If this orientation links together dead-ends |
| 688 | * with a total area of less than the entire |
| 689 | * grid, it is invalid. |
| 690 | * |
| 691 | * (We add 1 to deadendtotal because of the |
| 692 | * tile itself, of course; one tile linking |
| 693 | * dead ends of size 2 and 3 forms a subnetwork |
| 694 | * with a total area of 6, not 5.) |
| 695 | */ |
| 696 | if (deadendtotal > 0 && deadendtotal+1 < area) |
| 697 | valid = FALSE; |
| 698 | } else if (nnondeadends == 1) { |
| 699 | /* |
| 700 | * If this orientation links together one or |
| 701 | * more dead-ends with precisely one |
| 702 | * non-dead-end, then we may have to mark that |
| 703 | * non-dead-end as a dead end going the other |
| 704 | * way. However, it depends on whether all |
| 705 | * other orientations share the same property. |
| 706 | */ |
| 707 | deadendtotal++; |
| 708 | if (deadendmax[nondeadends[0]] < deadendtotal) |
| 709 | deadendmax[nondeadends[0]] = deadendtotal; |
| 710 | } else { |
| 711 | /* |
| 712 | * If this orientation links together two or |
| 713 | * more non-dead-ends, then we can rule out the |
| 714 | * possibility of putting in new dead-end |
| 715 | * markings in those directions. |
| 716 | */ |
| 717 | int k; |
| 718 | for (k = 0; k < nnondeadends; k++) |
| 719 | deadendmax[nondeadends[k]] = area+1; |
| 720 | } |
| 721 | |
| 722 | if (valid) |
| 723 | tilestate[(y*w+x) * 4 + j++] = val; |
| 724 | #ifdef SOLVER_DIAGNOSTICS |
| 725 | else |
| 726 | printf("ruling out orientation %x at %d,%d\n", val, x, y); |
| 727 | #endif |
| 728 | } |
| 729 | |
| 730 | assert(j > 0); /* we can't lose _all_ possibilities! */ |
| 731 | |
| 732 | if (j < i) { |
| 733 | done_something = TRUE; |
| 734 | |
| 735 | /* |
| 736 | * We have ruled out at least one tile orientation. |
| 737 | * Make sure the rest are blanked. |
| 738 | */ |
| 739 | while (j < 4) |
| 740 | tilestate[(y*w+x) * 4 + j++] = 255; |
| 741 | } |
| 742 | |
| 743 | /* |
| 744 | * Now go through the tile orientations again and see |
| 745 | * if we've deduced anything new about any edges. |
| 746 | */ |
| 747 | { |
| 748 | int a, o; |
| 749 | a = 0xF; o = 0; |
| 750 | |
| 751 | for (i = 0; i < 4 && tilestate[(y*w+x) * 4 + i] != 255; i++) { |
| 752 | a &= tilestate[(y*w+x) * 4 + i]; |
| 753 | o |= tilestate[(y*w+x) * 4 + i]; |
| 754 | } |
| 755 | for (d = 1; d <= 8; d += d) |
| 756 | if (edgestate[(y*w+x) * 5 + d] == 0) { |
| 757 | int x2, y2, d2; |
| 758 | OFFSETWH(x2, y2, x, y, d, w, h); |
| 759 | d2 = F(d); |
| 760 | if (a & d) { |
| 761 | /* This edge is open in all orientations. */ |
| 762 | #ifdef SOLVER_DIAGNOSTICS |
| 763 | printf("marking edge %d,%d:%d open\n", x, y, d); |
| 764 | #endif |
| 765 | edgestate[(y*w+x) * 5 + d] = 1; |
| 766 | edgestate[(y2*w+x2) * 5 + d2] = 1; |
| 767 | dsf_merge(equivalence, y*w+x, y2*w+x2); |
| 768 | done_something = TRUE; |
| 769 | todo_add(todo, y2*w+x2); |
| 770 | } else if (!(o & d)) { |
| 771 | /* This edge is closed in all orientations. */ |
| 772 | #ifdef SOLVER_DIAGNOSTICS |
| 773 | printf("marking edge %d,%d:%d closed\n", x, y, d); |
| 774 | #endif |
| 775 | edgestate[(y*w+x) * 5 + d] = 2; |
| 776 | edgestate[(y2*w+x2) * 5 + d2] = 2; |
| 777 | done_something = TRUE; |
| 778 | todo_add(todo, y2*w+x2); |
| 779 | } |
| 780 | } |
| 781 | |
| 782 | } |
| 783 | |
| 784 | /* |
| 785 | * Now check the dead-end markers and see if any of |
| 786 | * them has lowered from the real ones. |
| 787 | */ |
| 788 | for (d = 1; d <= 8; d += d) { |
| 789 | int x2, y2, d2; |
| 790 | OFFSETWH(x2, y2, x, y, d, w, h); |
| 791 | d2 = F(d); |
| 792 | if (deadendmax[d] > 0 && |
| 793 | deadends[(y2*w+x2) * 5 + d2] > deadendmax[d]) { |
| 794 | #ifdef SOLVER_DIAGNOSTICS |
| 795 | printf("setting dead end value %d,%d:%d to %d\n", |
| 796 | x2, y2, d2, deadendmax[d]); |
| 797 | #endif |
| 798 | deadends[(y2*w+x2) * 5 + d2] = deadendmax[d]; |
| 799 | done_something = TRUE; |
| 800 | todo_add(todo, y2*w+x2); |
| 801 | } |
| 802 | } |
| 803 | |
| 804 | } |
| 805 | } |
| 806 | |
| 807 | /* |
| 808 | * Mark all completely determined tiles as locked. |
| 809 | */ |
| 810 | j = TRUE; |
| 811 | for (i = 0; i < w*h; i++) { |
| 812 | if (tilestate[i * 4 + 1] == 255) { |
| 813 | assert(tilestate[i * 4 + 0] != 255); |
| 814 | tiles[i] = tilestate[i * 4] | LOCKED; |
| 815 | } else { |
| 816 | tiles[i] &= ~LOCKED; |
| 817 | j = FALSE; |
| 818 | } |
| 819 | } |
| 820 | |
| 821 | /* |
| 822 | * Free up working space. |
| 823 | */ |
| 824 | todo_free(todo); |
| 825 | sfree(tilestate); |
| 826 | sfree(edgestate); |
| 827 | sfree(deadends); |
| 828 | sfree(equivalence); |
| 829 | |
| 830 | return j; |
| 831 | } |
| 832 | |
| 833 | /* ---------------------------------------------------------------------- |
| 834 | * Randomly select a new game description. |
| 835 | */ |
| 836 | |
| 837 | /* |
| 838 | * Function to randomly perturb an ambiguous section in a grid, to |
| 839 | * attempt to ensure unique solvability. |
| 840 | */ |
| 841 | static void perturb(int w, int h, unsigned char *tiles, int wrapping, |
| 842 | random_state *rs, int startx, int starty, int startd) |
| 843 | { |
| 844 | struct xyd *perimeter, *perim2, *loop[2], looppos[2]; |
| 845 | int nperim, perimsize, nloop[2], loopsize[2]; |
| 846 | int x, y, d, i; |
| 847 | |
| 848 | /* |
| 849 | * We know that the tile at (startx,starty) is part of an |
| 850 | * ambiguous section, and we also know that its neighbour in |
| 851 | * direction startd is fully specified. We begin by tracing all |
| 852 | * the way round the ambiguous area. |
| 853 | */ |
| 854 | nperim = perimsize = 0; |
| 855 | perimeter = NULL; |
| 856 | x = startx; |
| 857 | y = starty; |
| 858 | d = startd; |
| 859 | #ifdef PERTURB_DIAGNOSTICS |
| 860 | printf("perturb %d,%d:%d\n", x, y, d); |
| 861 | #endif |
| 862 | do { |
| 863 | int x2, y2, d2; |
| 864 | |
| 865 | if (nperim >= perimsize) { |
| 866 | perimsize = perimsize * 3 / 2 + 32; |
| 867 | perimeter = sresize(perimeter, perimsize, struct xyd); |
| 868 | } |
| 869 | perimeter[nperim].x = x; |
| 870 | perimeter[nperim].y = y; |
| 871 | perimeter[nperim].direction = d; |
| 872 | nperim++; |
| 873 | #ifdef PERTURB_DIAGNOSTICS |
| 874 | printf("perimeter: %d,%d:%d\n", x, y, d); |
| 875 | #endif |
| 876 | |
| 877 | /* |
| 878 | * First, see if we can simply turn left from where we are |
| 879 | * and find another locked square. |
| 880 | */ |
| 881 | d2 = A(d); |
| 882 | OFFSETWH(x2, y2, x, y, d2, w, h); |
| 883 | if ((!wrapping && (abs(x2-x) > 1 || abs(y2-y) > 1)) || |
| 884 | (tiles[y2*w+x2] & LOCKED)) { |
| 885 | d = d2; |
| 886 | } else { |
| 887 | /* |
| 888 | * Failing that, step left into the new square and look |
| 889 | * in front of us. |
| 890 | */ |
| 891 | x = x2; |
| 892 | y = y2; |
| 893 | OFFSETWH(x2, y2, x, y, d, w, h); |
| 894 | if ((wrapping || (abs(x2-x) <= 1 && abs(y2-y) <= 1)) && |
| 895 | !(tiles[y2*w+x2] & LOCKED)) { |
| 896 | /* |
| 897 | * And failing _that_, we're going to have to step |
| 898 | * forward into _that_ square and look right at the |
| 899 | * same locked square as we started with. |
| 900 | */ |
| 901 | x = x2; |
| 902 | y = y2; |
| 903 | d = C(d); |
| 904 | } |
| 905 | } |
| 906 | |
| 907 | } while (x != startx || y != starty || d != startd); |
| 908 | |
| 909 | /* |
| 910 | * Our technique for perturbing this ambiguous area is to |
| 911 | * search round its edge for a join we can make: that is, an |
| 912 | * edge on the perimeter which is (a) not currently connected, |
| 913 | * and (b) connecting it would not yield a full cross on either |
| 914 | * side. Then we make that join, search round the network to |
| 915 | * find the loop thus constructed, and sever the loop at a |
| 916 | * randomly selected other point. |
| 917 | */ |
| 918 | perim2 = snewn(nperim, struct xyd); |
| 919 | memcpy(perim2, perimeter, nperim * sizeof(struct xyd)); |
| 920 | /* Shuffle the perimeter, so as to search it without directional bias. */ |
| 921 | shuffle(perim2, nperim, sizeof(*perim2), rs); |
| 922 | for (i = 0; i < nperim; i++) { |
| 923 | int x2, y2; |
| 924 | |
| 925 | x = perim2[i].x; |
| 926 | y = perim2[i].y; |
| 927 | d = perim2[i].direction; |
| 928 | |
| 929 | OFFSETWH(x2, y2, x, y, d, w, h); |
| 930 | if (!wrapping && (abs(x2-x) > 1 || abs(y2-y) > 1)) |
| 931 | continue; /* can't link across non-wrapping border */ |
| 932 | if (tiles[y*w+x] & d) |
| 933 | continue; /* already linked in this direction! */ |
| 934 | if (((tiles[y*w+x] | d) & 15) == 15) |
| 935 | continue; /* can't turn this tile into a cross */ |
| 936 | if (((tiles[y2*w+x2] | F(d)) & 15) == 15) |
| 937 | continue; /* can't turn other tile into a cross */ |
| 938 | |
| 939 | /* |
| 940 | * We've found the point at which we're going to make a new |
| 941 | * link. |
| 942 | */ |
| 943 | #ifdef PERTURB_DIAGNOSTICS |
| 944 | printf("linking %d,%d:%d\n", x, y, d); |
| 945 | #endif |
| 946 | tiles[y*w+x] |= d; |
| 947 | tiles[y2*w+x2] |= F(d); |
| 948 | |
| 949 | break; |
| 950 | } |
| 951 | sfree(perim2); |
| 952 | |
| 953 | if (i == nperim) { |
| 954 | sfree(perimeter); |
| 955 | return; /* nothing we can do! */ |
| 956 | } |
| 957 | |
| 958 | /* |
| 959 | * Now we've constructed a new link, we need to find the entire |
| 960 | * loop of which it is a part. |
| 961 | * |
| 962 | * In principle, this involves doing a complete search round |
| 963 | * the network. However, I anticipate that in the vast majority |
| 964 | * of cases the loop will be quite small, so what I'm going to |
| 965 | * do is make _two_ searches round the network in parallel, one |
| 966 | * keeping its metaphorical hand on the left-hand wall while |
| 967 | * the other keeps its hand on the right. As soon as one of |
| 968 | * them gets back to its starting point, I abandon the other. |
| 969 | */ |
| 970 | for (i = 0; i < 2; i++) { |
| 971 | loopsize[i] = nloop[i] = 0; |
| 972 | loop[i] = NULL; |
| 973 | looppos[i].x = x; |
| 974 | looppos[i].y = y; |
| 975 | looppos[i].direction = d; |
| 976 | } |
| 977 | while (1) { |
| 978 | for (i = 0; i < 2; i++) { |
| 979 | int x2, y2, j; |
| 980 | |
| 981 | x = looppos[i].x; |
| 982 | y = looppos[i].y; |
| 983 | d = looppos[i].direction; |
| 984 | |
| 985 | OFFSETWH(x2, y2, x, y, d, w, h); |
| 986 | |
| 987 | /* |
| 988 | * Add this path segment to the loop, unless it exactly |
| 989 | * reverses the previous one on the loop in which case |
| 990 | * we take it away again. |
| 991 | */ |
| 992 | #ifdef PERTURB_DIAGNOSTICS |
| 993 | printf("looppos[%d] = %d,%d:%d\n", i, x, y, d); |
| 994 | #endif |
| 995 | if (nloop[i] > 0 && |
| 996 | loop[i][nloop[i]-1].x == x2 && |
| 997 | loop[i][nloop[i]-1].y == y2 && |
| 998 | loop[i][nloop[i]-1].direction == F(d)) { |
| 999 | #ifdef PERTURB_DIAGNOSTICS |
| 1000 | printf("removing path segment %d,%d:%d from loop[%d]\n", |
| 1001 | x2, y2, F(d), i); |
| 1002 | #endif |
| 1003 | nloop[i]--; |
| 1004 | } else { |
| 1005 | if (nloop[i] >= loopsize[i]) { |
| 1006 | loopsize[i] = loopsize[i] * 3 / 2 + 32; |
| 1007 | loop[i] = sresize(loop[i], loopsize[i], struct xyd); |
| 1008 | } |
| 1009 | #ifdef PERTURB_DIAGNOSTICS |
| 1010 | printf("adding path segment %d,%d:%d to loop[%d]\n", |
| 1011 | x, y, d, i); |
| 1012 | #endif |
| 1013 | loop[i][nloop[i]++] = looppos[i]; |
| 1014 | } |
| 1015 | |
| 1016 | #ifdef PERTURB_DIAGNOSTICS |
| 1017 | printf("tile at new location is %x\n", tiles[y2*w+x2] & 0xF); |
| 1018 | #endif |
| 1019 | d = F(d); |
| 1020 | for (j = 0; j < 4; j++) { |
| 1021 | if (i == 0) |
| 1022 | d = A(d); |
| 1023 | else |
| 1024 | d = C(d); |
| 1025 | #ifdef PERTURB_DIAGNOSTICS |
| 1026 | printf("trying dir %d\n", d); |
| 1027 | #endif |
| 1028 | if (tiles[y2*w+x2] & d) { |
| 1029 | looppos[i].x = x2; |
| 1030 | looppos[i].y = y2; |
| 1031 | looppos[i].direction = d; |
| 1032 | break; |
| 1033 | } |
| 1034 | } |
| 1035 | |
| 1036 | assert(j < 4); |
| 1037 | assert(nloop[i] > 0); |
| 1038 | |
| 1039 | if (looppos[i].x == loop[i][0].x && |
| 1040 | looppos[i].y == loop[i][0].y && |
| 1041 | looppos[i].direction == loop[i][0].direction) { |
| 1042 | #ifdef PERTURB_DIAGNOSTICS |
| 1043 | printf("loop %d finished tracking\n", i); |
| 1044 | #endif |
| 1045 | |
| 1046 | /* |
| 1047 | * Having found our loop, we now sever it at a |
| 1048 | * randomly chosen point - absolutely any will do - |
| 1049 | * which is not the one we joined it at to begin |
| 1050 | * with. Conveniently, the one we joined it at is |
| 1051 | * loop[i][0], so we just avoid that one. |
| 1052 | */ |
| 1053 | j = random_upto(rs, nloop[i]-1) + 1; |
| 1054 | x = loop[i][j].x; |
| 1055 | y = loop[i][j].y; |
| 1056 | d = loop[i][j].direction; |
| 1057 | OFFSETWH(x2, y2, x, y, d, w, h); |
| 1058 | tiles[y*w+x] &= ~d; |
| 1059 | tiles[y2*w+x2] &= ~F(d); |
| 1060 | |
| 1061 | break; |
| 1062 | } |
| 1063 | } |
| 1064 | if (i < 2) |
| 1065 | break; |
| 1066 | } |
| 1067 | sfree(loop[0]); |
| 1068 | sfree(loop[1]); |
| 1069 | |
| 1070 | /* |
| 1071 | * Finally, we must mark the entire disputed section as locked, |
| 1072 | * to prevent the perturb function being called on it multiple |
| 1073 | * times. |
| 1074 | * |
| 1075 | * To do this, we _sort_ the perimeter of the area. The |
| 1076 | * existing xyd_cmp function will arrange things into columns |
| 1077 | * for us, in such a way that each column has the edges in |
| 1078 | * vertical order. Then we can work down each column and fill |
| 1079 | * in all the squares between an up edge and a down edge. |
| 1080 | */ |
| 1081 | qsort(perimeter, nperim, sizeof(struct xyd), xyd_cmp); |
| 1082 | x = y = -1; |
| 1083 | for (i = 0; i <= nperim; i++) { |
| 1084 | if (i == nperim || perimeter[i].x > x) { |
| 1085 | /* |
| 1086 | * Fill in everything from the last Up edge to the |
| 1087 | * bottom of the grid, if necessary. |
| 1088 | */ |
| 1089 | if (x != -1) { |
| 1090 | while (y < h) { |
| 1091 | #ifdef PERTURB_DIAGNOSTICS |
| 1092 | printf("resolved: locking tile %d,%d\n", x, y); |
| 1093 | #endif |
| 1094 | tiles[y * w + x] |= LOCKED; |
| 1095 | y++; |
| 1096 | } |
| 1097 | x = y = -1; |
| 1098 | } |
| 1099 | |
| 1100 | if (i == nperim) |
| 1101 | break; |
| 1102 | |
| 1103 | x = perimeter[i].x; |
| 1104 | y = 0; |
| 1105 | } |
| 1106 | |
| 1107 | if (perimeter[i].direction == U) { |
| 1108 | x = perimeter[i].x; |
| 1109 | y = perimeter[i].y; |
| 1110 | } else if (perimeter[i].direction == D) { |
| 1111 | /* |
| 1112 | * Fill in everything from the last Up edge to here. |
| 1113 | */ |
| 1114 | assert(x == perimeter[i].x && y <= perimeter[i].y); |
| 1115 | while (y <= perimeter[i].y) { |
| 1116 | #ifdef PERTURB_DIAGNOSTICS |
| 1117 | printf("resolved: locking tile %d,%d\n", x, y); |
| 1118 | #endif |
| 1119 | tiles[y * w + x] |= LOCKED; |
| 1120 | y++; |
| 1121 | } |
| 1122 | x = y = -1; |
| 1123 | } |
| 1124 | } |
| 1125 | |
| 1126 | sfree(perimeter); |
| 1127 | } |
| 1128 | |
| 1129 | static char *new_game_desc(game_params *params, random_state *rs, |
| 1130 | char **aux, int interactive) |
| 1131 | { |
| 1132 | tree234 *possibilities, *barriertree; |
| 1133 | int w, h, x, y, cx, cy, nbarriers; |
| 1134 | unsigned char *tiles, *barriers; |
| 1135 | char *desc, *p; |
| 1136 | |
| 1137 | w = params->width; |
| 1138 | h = params->height; |
| 1139 | |
| 1140 | cx = w / 2; |
| 1141 | cy = h / 2; |
| 1142 | |
| 1143 | tiles = snewn(w * h, unsigned char); |
| 1144 | barriers = snewn(w * h, unsigned char); |
| 1145 | |
| 1146 | begin_generation: |
| 1147 | |
| 1148 | memset(tiles, 0, w * h); |
| 1149 | memset(barriers, 0, w * h); |
| 1150 | |
| 1151 | /* |
| 1152 | * Construct the unshuffled grid. |
| 1153 | * |
| 1154 | * To do this, we simply start at the centre point, repeatedly |
| 1155 | * choose a random possibility out of the available ways to |
| 1156 | * extend a used square into an unused one, and do it. After |
| 1157 | * extending the third line out of a square, we remove the |
| 1158 | * fourth from the possibilities list to avoid any full-cross |
| 1159 | * squares (which would make the game too easy because they |
| 1160 | * only have one orientation). |
| 1161 | * |
| 1162 | * The slightly worrying thing is the avoidance of full-cross |
| 1163 | * squares. Can this cause our unsophisticated construction |
| 1164 | * algorithm to paint itself into a corner, by getting into a |
| 1165 | * situation where there are some unreached squares and the |
| 1166 | * only way to reach any of them is to extend a T-piece into a |
| 1167 | * full cross? |
| 1168 | * |
| 1169 | * Answer: no it can't, and here's a proof. |
| 1170 | * |
| 1171 | * Any contiguous group of such unreachable squares must be |
| 1172 | * surrounded on _all_ sides by T-pieces pointing away from the |
| 1173 | * group. (If not, then there is a square which can be extended |
| 1174 | * into one of the `unreachable' ones, and so it wasn't |
| 1175 | * unreachable after all.) In particular, this implies that |
| 1176 | * each contiguous group of unreachable squares must be |
| 1177 | * rectangular in shape (any deviation from that yields a |
| 1178 | * non-T-piece next to an `unreachable' square). |
| 1179 | * |
| 1180 | * So we have a rectangle of unreachable squares, with T-pieces |
| 1181 | * forming a solid border around the rectangle. The corners of |
| 1182 | * that border must be connected (since every tile connects all |
| 1183 | * the lines arriving in it), and therefore the border must |
| 1184 | * form a closed loop around the rectangle. |
| 1185 | * |
| 1186 | * But this can't have happened in the first place, since we |
| 1187 | * _know_ we've avoided creating closed loops! Hence, no such |
| 1188 | * situation can ever arise, and the naive grid construction |
| 1189 | * algorithm will guaranteeably result in a complete grid |
| 1190 | * containing no unreached squares, no full crosses _and_ no |
| 1191 | * closed loops. [] |
| 1192 | */ |
| 1193 | possibilities = newtree234(xyd_cmp_nc); |
| 1194 | |
| 1195 | if (cx+1 < w) |
| 1196 | add234(possibilities, new_xyd(cx, cy, R)); |
| 1197 | if (cy-1 >= 0) |
| 1198 | add234(possibilities, new_xyd(cx, cy, U)); |
| 1199 | if (cx-1 >= 0) |
| 1200 | add234(possibilities, new_xyd(cx, cy, L)); |
| 1201 | if (cy+1 < h) |
| 1202 | add234(possibilities, new_xyd(cx, cy, D)); |
| 1203 | |
| 1204 | while (count234(possibilities) > 0) { |
| 1205 | int i; |
| 1206 | struct xyd *xyd; |
| 1207 | int x1, y1, d1, x2, y2, d2, d; |
| 1208 | |
| 1209 | /* |
| 1210 | * Extract a randomly chosen possibility from the list. |
| 1211 | */ |
| 1212 | i = random_upto(rs, count234(possibilities)); |
| 1213 | xyd = delpos234(possibilities, i); |
| 1214 | x1 = xyd->x; |
| 1215 | y1 = xyd->y; |
| 1216 | d1 = xyd->direction; |
| 1217 | sfree(xyd); |
| 1218 | |
| 1219 | OFFSET(x2, y2, x1, y1, d1, params); |
| 1220 | d2 = F(d1); |
| 1221 | #ifdef GENERATION_DIAGNOSTICS |
| 1222 | printf("picked (%d,%d,%c) <-> (%d,%d,%c)\n", |
| 1223 | x1, y1, "0RU3L567D9abcdef"[d1], x2, y2, "0RU3L567D9abcdef"[d2]); |
| 1224 | #endif |
| 1225 | |
| 1226 | /* |
| 1227 | * Make the connection. (We should be moving to an as yet |
| 1228 | * unused tile.) |
| 1229 | */ |
| 1230 | index(params, tiles, x1, y1) |= d1; |
| 1231 | assert(index(params, tiles, x2, y2) == 0); |
| 1232 | index(params, tiles, x2, y2) |= d2; |
| 1233 | |
| 1234 | /* |
| 1235 | * If we have created a T-piece, remove its last |
| 1236 | * possibility. |
| 1237 | */ |
| 1238 | if (COUNT(index(params, tiles, x1, y1)) == 3) { |
| 1239 | struct xyd xyd1, *xydp; |
| 1240 | |
| 1241 | xyd1.x = x1; |
| 1242 | xyd1.y = y1; |
| 1243 | xyd1.direction = 0x0F ^ index(params, tiles, x1, y1); |
| 1244 | |
| 1245 | xydp = find234(possibilities, &xyd1, NULL); |
| 1246 | |
| 1247 | if (xydp) { |
| 1248 | #ifdef GENERATION_DIAGNOSTICS |
| 1249 | printf("T-piece; removing (%d,%d,%c)\n", |
| 1250 | xydp->x, xydp->y, "0RU3L567D9abcdef"[xydp->direction]); |
| 1251 | #endif |
| 1252 | del234(possibilities, xydp); |
| 1253 | sfree(xydp); |
| 1254 | } |
| 1255 | } |
| 1256 | |
| 1257 | /* |
| 1258 | * Remove all other possibilities that were pointing at the |
| 1259 | * tile we've just moved into. |
| 1260 | */ |
| 1261 | for (d = 1; d < 0x10; d <<= 1) { |
| 1262 | int x3, y3, d3; |
| 1263 | struct xyd xyd1, *xydp; |
| 1264 | |
| 1265 | OFFSET(x3, y3, x2, y2, d, params); |
| 1266 | d3 = F(d); |
| 1267 | |
| 1268 | xyd1.x = x3; |
| 1269 | xyd1.y = y3; |
| 1270 | xyd1.direction = d3; |
| 1271 | |
| 1272 | xydp = find234(possibilities, &xyd1, NULL); |
| 1273 | |
| 1274 | if (xydp) { |
| 1275 | #ifdef GENERATION_DIAGNOSTICS |
| 1276 | printf("Loop avoidance; removing (%d,%d,%c)\n", |
| 1277 | xydp->x, xydp->y, "0RU3L567D9abcdef"[xydp->direction]); |
| 1278 | #endif |
| 1279 | del234(possibilities, xydp); |
| 1280 | sfree(xydp); |
| 1281 | } |
| 1282 | } |
| 1283 | |
| 1284 | /* |
| 1285 | * Add new possibilities to the list for moving _out_ of |
| 1286 | * the tile we have just moved into. |
| 1287 | */ |
| 1288 | for (d = 1; d < 0x10; d <<= 1) { |
| 1289 | int x3, y3; |
| 1290 | |
| 1291 | if (d == d2) |
| 1292 | continue; /* we've got this one already */ |
| 1293 | |
| 1294 | if (!params->wrapping) { |
| 1295 | if (d == U && y2 == 0) |
| 1296 | continue; |
| 1297 | if (d == D && y2 == h-1) |
| 1298 | continue; |
| 1299 | if (d == L && x2 == 0) |
| 1300 | continue; |
| 1301 | if (d == R && x2 == w-1) |
| 1302 | continue; |
| 1303 | } |
| 1304 | |
| 1305 | OFFSET(x3, y3, x2, y2, d, params); |
| 1306 | |
| 1307 | if (index(params, tiles, x3, y3)) |
| 1308 | continue; /* this would create a loop */ |
| 1309 | |
| 1310 | #ifdef GENERATION_DIAGNOSTICS |
| 1311 | printf("New frontier; adding (%d,%d,%c)\n", |
| 1312 | x2, y2, "0RU3L567D9abcdef"[d]); |
| 1313 | #endif |
| 1314 | add234(possibilities, new_xyd(x2, y2, d)); |
| 1315 | } |
| 1316 | } |
| 1317 | /* Having done that, we should have no possibilities remaining. */ |
| 1318 | assert(count234(possibilities) == 0); |
| 1319 | freetree234(possibilities); |
| 1320 | |
| 1321 | if (params->unique) { |
| 1322 | int prevn = -1; |
| 1323 | |
| 1324 | /* |
| 1325 | * Run the solver to check unique solubility. |
| 1326 | */ |
| 1327 | while (!net_solver(w, h, tiles, NULL, params->wrapping)) { |
| 1328 | int n = 0; |
| 1329 | |
| 1330 | /* |
| 1331 | * We expect (in most cases) that most of the grid will |
| 1332 | * be uniquely specified already, and the remaining |
| 1333 | * ambiguous sections will be small and separate. So |
| 1334 | * our strategy is to find each individual such |
| 1335 | * section, and perform a perturbation on the network |
| 1336 | * in that area. |
| 1337 | */ |
| 1338 | for (y = 0; y < h; y++) for (x = 0; x < w; x++) { |
| 1339 | if (x+1 < w && ((tiles[y*w+x] ^ tiles[y*w+x+1]) & LOCKED)) { |
| 1340 | n++; |
| 1341 | if (tiles[y*w+x] & LOCKED) |
| 1342 | perturb(w, h, tiles, params->wrapping, rs, x+1, y, L); |
| 1343 | else |
| 1344 | perturb(w, h, tiles, params->wrapping, rs, x, y, R); |
| 1345 | } |
| 1346 | if (y+1 < h && ((tiles[y*w+x] ^ tiles[(y+1)*w+x]) & LOCKED)) { |
| 1347 | n++; |
| 1348 | if (tiles[y*w+x] & LOCKED) |
| 1349 | perturb(w, h, tiles, params->wrapping, rs, x, y+1, U); |
| 1350 | else |
| 1351 | perturb(w, h, tiles, params->wrapping, rs, x, y, D); |
| 1352 | } |
| 1353 | } |
| 1354 | |
| 1355 | /* |
| 1356 | * Now n counts the number of ambiguous sections we |
| 1357 | * have fiddled with. If we haven't managed to decrease |
| 1358 | * it from the last time we ran the solver, give up and |
| 1359 | * regenerate the entire grid. |
| 1360 | */ |
| 1361 | if (prevn != -1 && prevn <= n) |
| 1362 | goto begin_generation; /* (sorry) */ |
| 1363 | |
| 1364 | prevn = n; |
| 1365 | } |
| 1366 | |
| 1367 | /* |
| 1368 | * The solver will have left a lot of LOCKED bits lying |
| 1369 | * around in the tiles array. Remove them. |
| 1370 | */ |
| 1371 | for (x = 0; x < w*h; x++) |
| 1372 | tiles[x] &= ~LOCKED; |
| 1373 | } |
| 1374 | |
| 1375 | /* |
| 1376 | * Now compute a list of the possible barrier locations. |
| 1377 | */ |
| 1378 | barriertree = newtree234(xyd_cmp_nc); |
| 1379 | for (y = 0; y < h; y++) { |
| 1380 | for (x = 0; x < w; x++) { |
| 1381 | |
| 1382 | if (!(index(params, tiles, x, y) & R) && |
| 1383 | (params->wrapping || x < w-1)) |
| 1384 | add234(barriertree, new_xyd(x, y, R)); |
| 1385 | if (!(index(params, tiles, x, y) & D) && |
| 1386 | (params->wrapping || y < h-1)) |
| 1387 | add234(barriertree, new_xyd(x, y, D)); |
| 1388 | } |
| 1389 | } |
| 1390 | |
| 1391 | /* |
| 1392 | * Save the unshuffled grid in aux. |
| 1393 | */ |
| 1394 | { |
| 1395 | char *solution; |
| 1396 | int i; |
| 1397 | |
| 1398 | solution = snewn(w * h + 1, char); |
| 1399 | for (i = 0; i < w * h; i++) |
| 1400 | solution[i] = "0123456789abcdef"[tiles[i] & 0xF]; |
| 1401 | solution[w*h] = '\0'; |
| 1402 | |
| 1403 | *aux = solution; |
| 1404 | } |
| 1405 | |
| 1406 | /* |
| 1407 | * Now shuffle the grid. |
| 1408 | * |
| 1409 | * In order to avoid accidentally generating an already-solved |
| 1410 | * grid, we will reshuffle as necessary to ensure that at least |
| 1411 | * one edge has a mismatched connection. |
| 1412 | * |
| 1413 | * This can always be done, since validate_params() enforces a |
| 1414 | * grid area of at least 2 and our generator never creates |
| 1415 | * either type of rotationally invariant tile (cross and |
| 1416 | * blank). Hence there must be at least one edge separating |
| 1417 | * distinct tiles, and it must be possible to find orientations |
| 1418 | * of those tiles such that one tile is trying to connect |
| 1419 | * through that edge and the other is not. |
| 1420 | * |
| 1421 | * (We could be more subtle, and allow the shuffle to generate |
| 1422 | * a grid in which all tiles match up locally and the only |
| 1423 | * criterion preventing the grid from being already solved is |
| 1424 | * connectedness. However, that would take more effort, and |
| 1425 | * it's easier to simply make sure every grid is _obviously_ |
| 1426 | * not solved.) |
| 1427 | */ |
| 1428 | while (1) { |
| 1429 | int mismatches; |
| 1430 | |
| 1431 | for (y = 0; y < h; y++) { |
| 1432 | for (x = 0; x < w; x++) { |
| 1433 | int orig = index(params, tiles, x, y); |
| 1434 | int rot = random_upto(rs, 4); |
| 1435 | index(params, tiles, x, y) = ROT(orig, rot); |
| 1436 | } |
| 1437 | } |
| 1438 | |
| 1439 | mismatches = 0; |
| 1440 | /* |
| 1441 | * I can't even be bothered to check for mismatches across |
| 1442 | * a wrapping edge, so I'm just going to enforce that there |
| 1443 | * must be a mismatch across a non-wrapping edge, which is |
| 1444 | * still always possible. |
| 1445 | */ |
| 1446 | for (y = 0; y < h; y++) for (x = 0; x < w; x++) { |
| 1447 | if (x+1 < w && ((ROT(index(params, tiles, x, y), 2) ^ |
| 1448 | index(params, tiles, x+1, y)) & L)) |
| 1449 | mismatches++; |
| 1450 | if (y+1 < h && ((ROT(index(params, tiles, x, y), 2) ^ |
| 1451 | index(params, tiles, x, y+1)) & U)) |
| 1452 | mismatches++; |
| 1453 | } |
| 1454 | |
| 1455 | if (mismatches > 0) |
| 1456 | break; |
| 1457 | } |
| 1458 | |
| 1459 | /* |
| 1460 | * And now choose barrier locations. (We carefully do this |
| 1461 | * _after_ shuffling, so that changing the barrier rate in the |
| 1462 | * params while keeping the random seed the same will give the |
| 1463 | * same shuffled grid and _only_ change the barrier locations. |
| 1464 | * Also the way we choose barrier locations, by repeatedly |
| 1465 | * choosing one possibility from the list until we have enough, |
| 1466 | * is designed to ensure that raising the barrier rate while |
| 1467 | * keeping the seed the same will provide a superset of the |
| 1468 | * previous barrier set - i.e. if you ask for 10 barriers, and |
| 1469 | * then decide that's still too hard and ask for 20, you'll get |
| 1470 | * the original 10 plus 10 more, rather than getting 20 new |
| 1471 | * ones and the chance of remembering your first 10.) |
| 1472 | */ |
| 1473 | nbarriers = (int)(params->barrier_probability * count234(barriertree)); |
| 1474 | assert(nbarriers >= 0 && nbarriers <= count234(barriertree)); |
| 1475 | |
| 1476 | while (nbarriers > 0) { |
| 1477 | int i; |
| 1478 | struct xyd *xyd; |
| 1479 | int x1, y1, d1, x2, y2, d2; |
| 1480 | |
| 1481 | /* |
| 1482 | * Extract a randomly chosen barrier from the list. |
| 1483 | */ |
| 1484 | i = random_upto(rs, count234(barriertree)); |
| 1485 | xyd = delpos234(barriertree, i); |
| 1486 | |
| 1487 | assert(xyd != NULL); |
| 1488 | |
| 1489 | x1 = xyd->x; |
| 1490 | y1 = xyd->y; |
| 1491 | d1 = xyd->direction; |
| 1492 | sfree(xyd); |
| 1493 | |
| 1494 | OFFSET(x2, y2, x1, y1, d1, params); |
| 1495 | d2 = F(d1); |
| 1496 | |
| 1497 | index(params, barriers, x1, y1) |= d1; |
| 1498 | index(params, barriers, x2, y2) |= d2; |
| 1499 | |
| 1500 | nbarriers--; |
| 1501 | } |
| 1502 | |
| 1503 | /* |
| 1504 | * Clean up the rest of the barrier list. |
| 1505 | */ |
| 1506 | { |
| 1507 | struct xyd *xyd; |
| 1508 | |
| 1509 | while ( (xyd = delpos234(barriertree, 0)) != NULL) |
| 1510 | sfree(xyd); |
| 1511 | |
| 1512 | freetree234(barriertree); |
| 1513 | } |
| 1514 | |
| 1515 | /* |
| 1516 | * Finally, encode the grid into a string game description. |
| 1517 | * |
| 1518 | * My syntax is extremely simple: each square is encoded as a |
| 1519 | * hex digit in which bit 0 means a connection on the right, |
| 1520 | * bit 1 means up, bit 2 left and bit 3 down. (i.e. the same |
| 1521 | * encoding as used internally). Each digit is followed by |
| 1522 | * optional barrier indicators: `v' means a vertical barrier to |
| 1523 | * the right of it, and `h' means a horizontal barrier below |
| 1524 | * it. |
| 1525 | */ |
| 1526 | desc = snewn(w * h * 3 + 1, char); |
| 1527 | p = desc; |
| 1528 | for (y = 0; y < h; y++) { |
| 1529 | for (x = 0; x < w; x++) { |
| 1530 | *p++ = "0123456789abcdef"[index(params, tiles, x, y)]; |
| 1531 | if ((params->wrapping || x < w-1) && |
| 1532 | (index(params, barriers, x, y) & R)) |
| 1533 | *p++ = 'v'; |
| 1534 | if ((params->wrapping || y < h-1) && |
| 1535 | (index(params, barriers, x, y) & D)) |
| 1536 | *p++ = 'h'; |
| 1537 | } |
| 1538 | } |
| 1539 | assert(p - desc <= w*h*3); |
| 1540 | *p = '\0'; |
| 1541 | |
| 1542 | sfree(tiles); |
| 1543 | sfree(barriers); |
| 1544 | |
| 1545 | return desc; |
| 1546 | } |
| 1547 | |
| 1548 | static char *validate_desc(game_params *params, char *desc) |
| 1549 | { |
| 1550 | int w = params->width, h = params->height; |
| 1551 | int i; |
| 1552 | |
| 1553 | for (i = 0; i < w*h; i++) { |
| 1554 | if (*desc >= '0' && *desc <= '9') |
| 1555 | /* OK */; |
| 1556 | else if (*desc >= 'a' && *desc <= 'f') |
| 1557 | /* OK */; |
| 1558 | else if (*desc >= 'A' && *desc <= 'F') |
| 1559 | /* OK */; |
| 1560 | else if (!*desc) |
| 1561 | return "Game description shorter than expected"; |
| 1562 | else |
| 1563 | return "Game description contained unexpected character"; |
| 1564 | desc++; |
| 1565 | while (*desc == 'h' || *desc == 'v') |
| 1566 | desc++; |
| 1567 | } |
| 1568 | if (*desc) |
| 1569 | return "Game description longer than expected"; |
| 1570 | |
| 1571 | return NULL; |
| 1572 | } |
| 1573 | |
| 1574 | /* ---------------------------------------------------------------------- |
| 1575 | * Construct an initial game state, given a description and parameters. |
| 1576 | */ |
| 1577 | |
| 1578 | static game_state *new_game(midend *me, game_params *params, char *desc) |
| 1579 | { |
| 1580 | game_state *state; |
| 1581 | int w, h, x, y; |
| 1582 | |
| 1583 | assert(params->width > 0 && params->height > 0); |
| 1584 | assert(params->width > 1 || params->height > 1); |
| 1585 | |
| 1586 | /* |
| 1587 | * Create a blank game state. |
| 1588 | */ |
| 1589 | state = snew(game_state); |
| 1590 | w = state->width = params->width; |
| 1591 | h = state->height = params->height; |
| 1592 | state->wrapping = params->wrapping; |
| 1593 | state->last_rotate_dir = state->last_rotate_x = state->last_rotate_y = 0; |
| 1594 | state->completed = state->used_solve = FALSE; |
| 1595 | state->tiles = snewn(state->width * state->height, unsigned char); |
| 1596 | memset(state->tiles, 0, state->width * state->height); |
| 1597 | state->barriers = snewn(state->width * state->height, unsigned char); |
| 1598 | memset(state->barriers, 0, state->width * state->height); |
| 1599 | |
| 1600 | /* |
| 1601 | * Parse the game description into the grid. |
| 1602 | */ |
| 1603 | for (y = 0; y < h; y++) { |
| 1604 | for (x = 0; x < w; x++) { |
| 1605 | if (*desc >= '0' && *desc <= '9') |
| 1606 | tile(state, x, y) = *desc - '0'; |
| 1607 | else if (*desc >= 'a' && *desc <= 'f') |
| 1608 | tile(state, x, y) = *desc - 'a' + 10; |
| 1609 | else if (*desc >= 'A' && *desc <= 'F') |
| 1610 | tile(state, x, y) = *desc - 'A' + 10; |
| 1611 | if (*desc) |
| 1612 | desc++; |
| 1613 | while (*desc == 'h' || *desc == 'v') { |
| 1614 | int x2, y2, d1, d2; |
| 1615 | if (*desc == 'v') |
| 1616 | d1 = R; |
| 1617 | else |
| 1618 | d1 = D; |
| 1619 | |
| 1620 | OFFSET(x2, y2, x, y, d1, state); |
| 1621 | d2 = F(d1); |
| 1622 | |
| 1623 | barrier(state, x, y) |= d1; |
| 1624 | barrier(state, x2, y2) |= d2; |
| 1625 | |
| 1626 | desc++; |
| 1627 | } |
| 1628 | } |
| 1629 | } |
| 1630 | |
| 1631 | /* |
| 1632 | * Set up border barriers if this is a non-wrapping game. |
| 1633 | */ |
| 1634 | if (!state->wrapping) { |
| 1635 | for (x = 0; x < state->width; x++) { |
| 1636 | barrier(state, x, 0) |= U; |
| 1637 | barrier(state, x, state->height-1) |= D; |
| 1638 | } |
| 1639 | for (y = 0; y < state->height; y++) { |
| 1640 | barrier(state, 0, y) |= L; |
| 1641 | barrier(state, state->width-1, y) |= R; |
| 1642 | } |
| 1643 | } else { |
| 1644 | /* |
| 1645 | * We check whether this is de-facto a non-wrapping game |
| 1646 | * despite the parameters, in case we were passed the |
| 1647 | * description of a non-wrapping game. This is so that we |
| 1648 | * can change some aspects of the UI behaviour. |
| 1649 | */ |
| 1650 | state->wrapping = FALSE; |
| 1651 | for (x = 0; x < state->width; x++) |
| 1652 | if (!(barrier(state, x, 0) & U) || |
| 1653 | !(barrier(state, x, state->height-1) & D)) |
| 1654 | state->wrapping = TRUE; |
| 1655 | for (y = 0; y < state->height; y++) |
| 1656 | if (!(barrier(state, 0, y) & L) || |
| 1657 | !(barrier(state, state->width-1, y) & R)) |
| 1658 | state->wrapping = TRUE; |
| 1659 | } |
| 1660 | |
| 1661 | return state; |
| 1662 | } |
| 1663 | |
| 1664 | static game_state *dup_game(game_state *state) |
| 1665 | { |
| 1666 | game_state *ret; |
| 1667 | |
| 1668 | ret = snew(game_state); |
| 1669 | ret->width = state->width; |
| 1670 | ret->height = state->height; |
| 1671 | ret->wrapping = state->wrapping; |
| 1672 | ret->completed = state->completed; |
| 1673 | ret->used_solve = state->used_solve; |
| 1674 | ret->last_rotate_dir = state->last_rotate_dir; |
| 1675 | ret->last_rotate_x = state->last_rotate_x; |
| 1676 | ret->last_rotate_y = state->last_rotate_y; |
| 1677 | ret->tiles = snewn(state->width * state->height, unsigned char); |
| 1678 | memcpy(ret->tiles, state->tiles, state->width * state->height); |
| 1679 | ret->barriers = snewn(state->width * state->height, unsigned char); |
| 1680 | memcpy(ret->barriers, state->barriers, state->width * state->height); |
| 1681 | |
| 1682 | return ret; |
| 1683 | } |
| 1684 | |
| 1685 | static void free_game(game_state *state) |
| 1686 | { |
| 1687 | sfree(state->tiles); |
| 1688 | sfree(state->barriers); |
| 1689 | sfree(state); |
| 1690 | } |
| 1691 | |
| 1692 | static char *solve_game(game_state *state, game_state *currstate, |
| 1693 | char *aux, char **error) |
| 1694 | { |
| 1695 | unsigned char *tiles; |
| 1696 | char *ret; |
| 1697 | int retlen, retsize; |
| 1698 | int i; |
| 1699 | |
| 1700 | tiles = snewn(state->width * state->height, unsigned char); |
| 1701 | |
| 1702 | if (!aux) { |
| 1703 | /* |
| 1704 | * Run the internal solver on the provided grid. This might |
| 1705 | * not yield a complete solution. |
| 1706 | */ |
| 1707 | memcpy(tiles, state->tiles, state->width * state->height); |
| 1708 | net_solver(state->width, state->height, tiles, |
| 1709 | state->barriers, state->wrapping); |
| 1710 | } else { |
| 1711 | for (i = 0; i < state->width * state->height; i++) { |
| 1712 | int c = aux[i]; |
| 1713 | |
| 1714 | if (c >= '0' && c <= '9') |
| 1715 | tiles[i] = c - '0'; |
| 1716 | else if (c >= 'a' && c <= 'f') |
| 1717 | tiles[i] = c - 'a' + 10; |
| 1718 | else if (c >= 'A' && c <= 'F') |
| 1719 | tiles[i] = c - 'A' + 10; |
| 1720 | |
| 1721 | tiles[i] |= LOCKED; |
| 1722 | } |
| 1723 | } |
| 1724 | |
| 1725 | /* |
| 1726 | * Now construct a string which can be passed to execute_move() |
| 1727 | * to transform the current grid into the solved one. |
| 1728 | */ |
| 1729 | retsize = 256; |
| 1730 | ret = snewn(retsize, char); |
| 1731 | retlen = 0; |
| 1732 | ret[retlen++] = 'S'; |
| 1733 | |
| 1734 | for (i = 0; i < state->width * state->height; i++) { |
| 1735 | int from = currstate->tiles[i], to = tiles[i]; |
| 1736 | int ft = from & (R|L|U|D), tt = to & (R|L|U|D); |
| 1737 | int x = i % state->width, y = i / state->width; |
| 1738 | int chr = '\0'; |
| 1739 | char buf[80], *p = buf; |
| 1740 | |
| 1741 | if (from == to) |
| 1742 | continue; /* nothing needs doing at all */ |
| 1743 | |
| 1744 | /* |
| 1745 | * To transform this tile into the desired tile: first |
| 1746 | * unlock the tile if it's locked, then rotate it if |
| 1747 | * necessary, then lock it if necessary. |
| 1748 | */ |
| 1749 | if (from & LOCKED) |
| 1750 | p += sprintf(p, ";L%d,%d", x, y); |
| 1751 | |
| 1752 | if (tt == A(ft)) |
| 1753 | chr = 'A'; |
| 1754 | else if (tt == C(ft)) |
| 1755 | chr = 'C'; |
| 1756 | else if (tt == F(ft)) |
| 1757 | chr = 'F'; |
| 1758 | else { |
| 1759 | assert(tt == ft); |
| 1760 | chr = '\0'; |
| 1761 | } |
| 1762 | if (chr) |
| 1763 | p += sprintf(p, ";%c%d,%d", chr, x, y); |
| 1764 | |
| 1765 | if (to & LOCKED) |
| 1766 | p += sprintf(p, ";L%d,%d", x, y); |
| 1767 | |
| 1768 | if (p > buf) { |
| 1769 | if (retlen + (p - buf) >= retsize) { |
| 1770 | retsize = retlen + (p - buf) + 512; |
| 1771 | ret = sresize(ret, retsize, char); |
| 1772 | } |
| 1773 | memcpy(ret+retlen, buf, p - buf); |
| 1774 | retlen += p - buf; |
| 1775 | } |
| 1776 | } |
| 1777 | |
| 1778 | assert(retlen < retsize); |
| 1779 | ret[retlen] = '\0'; |
| 1780 | ret = sresize(ret, retlen+1, char); |
| 1781 | |
| 1782 | sfree(tiles); |
| 1783 | |
| 1784 | return ret; |
| 1785 | } |
| 1786 | |
| 1787 | static int game_can_format_as_text_now(game_params *params) |
| 1788 | { |
| 1789 | return TRUE; |
| 1790 | } |
| 1791 | |
| 1792 | static char *game_text_format(game_state *state) |
| 1793 | { |
| 1794 | return NULL; |
| 1795 | } |
| 1796 | |
| 1797 | /* ---------------------------------------------------------------------- |
| 1798 | * Utility routine. |
| 1799 | */ |
| 1800 | |
| 1801 | /* |
| 1802 | * Compute which squares are reachable from the centre square, as a |
| 1803 | * quick visual aid to determining how close the game is to |
| 1804 | * completion. This is also a simple way to tell if the game _is_ |
| 1805 | * completed - just call this function and see whether every square |
| 1806 | * is marked active. |
| 1807 | */ |
| 1808 | static unsigned char *compute_active(game_state *state, int cx, int cy) |
| 1809 | { |
| 1810 | unsigned char *active; |
| 1811 | tree234 *todo; |
| 1812 | struct xyd *xyd; |
| 1813 | |
| 1814 | active = snewn(state->width * state->height, unsigned char); |
| 1815 | memset(active, 0, state->width * state->height); |
| 1816 | |
| 1817 | /* |
| 1818 | * We only store (x,y) pairs in todo, but it's easier to reuse |
| 1819 | * xyd_cmp and just store direction 0 every time. |
| 1820 | */ |
| 1821 | todo = newtree234(xyd_cmp_nc); |
| 1822 | index(state, active, cx, cy) = ACTIVE; |
| 1823 | add234(todo, new_xyd(cx, cy, 0)); |
| 1824 | |
| 1825 | while ( (xyd = delpos234(todo, 0)) != NULL) { |
| 1826 | int x1, y1, d1, x2, y2, d2; |
| 1827 | |
| 1828 | x1 = xyd->x; |
| 1829 | y1 = xyd->y; |
| 1830 | sfree(xyd); |
| 1831 | |
| 1832 | for (d1 = 1; d1 < 0x10; d1 <<= 1) { |
| 1833 | OFFSET(x2, y2, x1, y1, d1, state); |
| 1834 | d2 = F(d1); |
| 1835 | |
| 1836 | /* |
| 1837 | * If the next tile in this direction is connected to |
| 1838 | * us, and there isn't a barrier in the way, and it |
| 1839 | * isn't already marked active, then mark it active and |
| 1840 | * add it to the to-examine list. |
| 1841 | */ |
| 1842 | if ((tile(state, x1, y1) & d1) && |
| 1843 | (tile(state, x2, y2) & d2) && |
| 1844 | !(barrier(state, x1, y1) & d1) && |
| 1845 | !index(state, active, x2, y2)) { |
| 1846 | index(state, active, x2, y2) = ACTIVE; |
| 1847 | add234(todo, new_xyd(x2, y2, 0)); |
| 1848 | } |
| 1849 | } |
| 1850 | } |
| 1851 | /* Now we expect the todo list to have shrunk to zero size. */ |
| 1852 | assert(count234(todo) == 0); |
| 1853 | freetree234(todo); |
| 1854 | |
| 1855 | return active; |
| 1856 | } |
| 1857 | |
| 1858 | struct game_ui { |
| 1859 | int org_x, org_y; /* origin */ |
| 1860 | int cx, cy; /* source tile (game coordinates) */ |
| 1861 | int cur_x, cur_y; |
| 1862 | int cur_visible; |
| 1863 | random_state *rs; /* used for jumbling */ |
| 1864 | #ifdef USE_DRAGGING |
| 1865 | int dragtilex, dragtiley, dragstartx, dragstarty, dragged; |
| 1866 | #endif |
| 1867 | }; |
| 1868 | |
| 1869 | static game_ui *new_ui(game_state *state) |
| 1870 | { |
| 1871 | void *seed; |
| 1872 | int seedsize; |
| 1873 | game_ui *ui = snew(game_ui); |
| 1874 | ui->org_x = ui->org_y = 0; |
| 1875 | ui->cur_x = ui->cx = state->width / 2; |
| 1876 | ui->cur_y = ui->cy = state->height / 2; |
| 1877 | ui->cur_visible = FALSE; |
| 1878 | get_random_seed(&seed, &seedsize); |
| 1879 | ui->rs = random_new(seed, seedsize); |
| 1880 | sfree(seed); |
| 1881 | |
| 1882 | return ui; |
| 1883 | } |
| 1884 | |
| 1885 | static void free_ui(game_ui *ui) |
| 1886 | { |
| 1887 | random_free(ui->rs); |
| 1888 | sfree(ui); |
| 1889 | } |
| 1890 | |
| 1891 | static char *encode_ui(game_ui *ui) |
| 1892 | { |
| 1893 | char buf[120]; |
| 1894 | /* |
| 1895 | * We preserve the origin and centre-point coordinates over a |
| 1896 | * serialise. |
| 1897 | */ |
| 1898 | sprintf(buf, "O%d,%d;C%d,%d", ui->org_x, ui->org_y, ui->cx, ui->cy); |
| 1899 | return dupstr(buf); |
| 1900 | } |
| 1901 | |
| 1902 | static void decode_ui(game_ui *ui, char *encoding) |
| 1903 | { |
| 1904 | sscanf(encoding, "O%d,%d;C%d,%d", |
| 1905 | &ui->org_x, &ui->org_y, &ui->cx, &ui->cy); |
| 1906 | } |
| 1907 | |
| 1908 | static void game_changed_state(game_ui *ui, game_state *oldstate, |
| 1909 | game_state *newstate) |
| 1910 | { |
| 1911 | } |
| 1912 | |
| 1913 | struct game_drawstate { |
| 1914 | int started; |
| 1915 | int width, height; |
| 1916 | int org_x, org_y; |
| 1917 | int tilesize; |
| 1918 | unsigned char *visible; |
| 1919 | }; |
| 1920 | |
| 1921 | /* ---------------------------------------------------------------------- |
| 1922 | * Process a move. |
| 1923 | */ |
| 1924 | static char *interpret_move(game_state *state, game_ui *ui, |
| 1925 | game_drawstate *ds, int x, int y, int button) |
| 1926 | { |
| 1927 | char *nullret; |
| 1928 | int tx = -1, ty = -1, dir = 0; |
| 1929 | int shift = button & MOD_SHFT, ctrl = button & MOD_CTRL; |
| 1930 | enum { |
| 1931 | NONE, ROTATE_LEFT, ROTATE_180, ROTATE_RIGHT, TOGGLE_LOCK, JUMBLE, |
| 1932 | MOVE_ORIGIN, MOVE_SOURCE, MOVE_ORIGIN_AND_SOURCE, MOVE_CURSOR |
| 1933 | } action; |
| 1934 | |
| 1935 | button &= ~MOD_MASK; |
| 1936 | nullret = NULL; |
| 1937 | action = NONE; |
| 1938 | |
| 1939 | if (button == LEFT_BUTTON || |
| 1940 | button == MIDDLE_BUTTON || |
| 1941 | #ifdef USE_DRAGGING |
| 1942 | button == LEFT_DRAG || |
| 1943 | button == LEFT_RELEASE || |
| 1944 | button == RIGHT_DRAG || |
| 1945 | button == RIGHT_RELEASE || |
| 1946 | #endif |
| 1947 | button == RIGHT_BUTTON) { |
| 1948 | |
| 1949 | if (ui->cur_visible) { |
| 1950 | ui->cur_visible = FALSE; |
| 1951 | nullret = ""; |
| 1952 | } |
| 1953 | |
| 1954 | /* |
| 1955 | * The button must have been clicked on a valid tile. |
| 1956 | */ |
| 1957 | x -= WINDOW_OFFSET + TILE_BORDER; |
| 1958 | y -= WINDOW_OFFSET + TILE_BORDER; |
| 1959 | if (x < 0 || y < 0) |
| 1960 | return nullret; |
| 1961 | tx = x / TILE_SIZE; |
| 1962 | ty = y / TILE_SIZE; |
| 1963 | if (tx >= state->width || ty >= state->height) |
| 1964 | return nullret; |
| 1965 | /* Transform from physical to game coords */ |
| 1966 | tx = (tx + ui->org_x) % state->width; |
| 1967 | ty = (ty + ui->org_y) % state->height; |
| 1968 | if (x % TILE_SIZE >= TILE_SIZE - TILE_BORDER || |
| 1969 | y % TILE_SIZE >= TILE_SIZE - TILE_BORDER) |
| 1970 | return nullret; |
| 1971 | |
| 1972 | #ifdef USE_DRAGGING |
| 1973 | |
| 1974 | if (button == MIDDLE_BUTTON |
| 1975 | #ifdef STYLUS_BASED |
| 1976 | || button == RIGHT_BUTTON /* with a stylus, `right-click' locks */ |
| 1977 | #endif |
| 1978 | ) { |
| 1979 | /* |
| 1980 | * Middle button never drags: it only toggles the lock. |
| 1981 | */ |
| 1982 | action = TOGGLE_LOCK; |
| 1983 | } else if (button == LEFT_BUTTON |
| 1984 | #ifndef STYLUS_BASED |
| 1985 | || button == RIGHT_BUTTON /* (see above) */ |
| 1986 | #endif |
| 1987 | ) { |
| 1988 | /* |
| 1989 | * Otherwise, we note down the start point for a drag. |
| 1990 | */ |
| 1991 | ui->dragtilex = tx; |
| 1992 | ui->dragtiley = ty; |
| 1993 | ui->dragstartx = x % TILE_SIZE; |
| 1994 | ui->dragstarty = y % TILE_SIZE; |
| 1995 | ui->dragged = FALSE; |
| 1996 | return nullret; /* no actual action */ |
| 1997 | } else if (button == LEFT_DRAG |
| 1998 | #ifndef STYLUS_BASED |
| 1999 | || button == RIGHT_DRAG |
| 2000 | #endif |
| 2001 | ) { |
| 2002 | /* |
| 2003 | * Find the new drag point and see if it necessitates a |
| 2004 | * rotation. |
| 2005 | */ |
| 2006 | int x0,y0, xA,yA, xC,yC, xF,yF; |
| 2007 | int mx, my; |
| 2008 | int d0, dA, dC, dF, dmin; |
| 2009 | |
| 2010 | tx = ui->dragtilex; |
| 2011 | ty = ui->dragtiley; |
| 2012 | |
| 2013 | mx = x - (ui->dragtilex * TILE_SIZE); |
| 2014 | my = y - (ui->dragtiley * TILE_SIZE); |
| 2015 | |
| 2016 | x0 = ui->dragstartx; |
| 2017 | y0 = ui->dragstarty; |
| 2018 | xA = ui->dragstarty; |
| 2019 | yA = TILE_SIZE-1 - ui->dragstartx; |
| 2020 | xF = TILE_SIZE-1 - ui->dragstartx; |
| 2021 | yF = TILE_SIZE-1 - ui->dragstarty; |
| 2022 | xC = TILE_SIZE-1 - ui->dragstarty; |
| 2023 | yC = ui->dragstartx; |
| 2024 | |
| 2025 | d0 = (mx-x0)*(mx-x0) + (my-y0)*(my-y0); |
| 2026 | dA = (mx-xA)*(mx-xA) + (my-yA)*(my-yA); |
| 2027 | dF = (mx-xF)*(mx-xF) + (my-yF)*(my-yF); |
| 2028 | dC = (mx-xC)*(mx-xC) + (my-yC)*(my-yC); |
| 2029 | |
| 2030 | dmin = min(min(d0,dA),min(dF,dC)); |
| 2031 | |
| 2032 | if (d0 == dmin) { |
| 2033 | return nullret; |
| 2034 | } else if (dF == dmin) { |
| 2035 | action = ROTATE_180; |
| 2036 | ui->dragstartx = xF; |
| 2037 | ui->dragstarty = yF; |
| 2038 | ui->dragged = TRUE; |
| 2039 | } else if (dA == dmin) { |
| 2040 | action = ROTATE_LEFT; |
| 2041 | ui->dragstartx = xA; |
| 2042 | ui->dragstarty = yA; |
| 2043 | ui->dragged = TRUE; |
| 2044 | } else /* dC == dmin */ { |
| 2045 | action = ROTATE_RIGHT; |
| 2046 | ui->dragstartx = xC; |
| 2047 | ui->dragstarty = yC; |
| 2048 | ui->dragged = TRUE; |
| 2049 | } |
| 2050 | } else if (button == LEFT_RELEASE |
| 2051 | #ifndef STYLUS_BASED |
| 2052 | || button == RIGHT_RELEASE |
| 2053 | #endif |
| 2054 | ) { |
| 2055 | if (!ui->dragged) { |
| 2056 | /* |
| 2057 | * There was a click but no perceptible drag: |
| 2058 | * revert to single-click behaviour. |
| 2059 | */ |
| 2060 | tx = ui->dragtilex; |
| 2061 | ty = ui->dragtiley; |
| 2062 | |
| 2063 | if (button == LEFT_RELEASE) |
| 2064 | action = ROTATE_LEFT; |
| 2065 | else |
| 2066 | action = ROTATE_RIGHT; |
| 2067 | } else |
| 2068 | return nullret; /* no action */ |
| 2069 | } |
| 2070 | |
| 2071 | #else /* USE_DRAGGING */ |
| 2072 | |
| 2073 | action = (button == LEFT_BUTTON ? ROTATE_LEFT : |
| 2074 | button == RIGHT_BUTTON ? ROTATE_RIGHT : TOGGLE_LOCK); |
| 2075 | |
| 2076 | #endif /* USE_DRAGGING */ |
| 2077 | |
| 2078 | } else if (IS_CURSOR_MOVE(button)) { |
| 2079 | switch (button) { |
| 2080 | case CURSOR_UP: dir = U; break; |
| 2081 | case CURSOR_DOWN: dir = D; break; |
| 2082 | case CURSOR_LEFT: dir = L; break; |
| 2083 | case CURSOR_RIGHT: dir = R; break; |
| 2084 | default: return nullret; |
| 2085 | } |
| 2086 | if (shift && ctrl) action = MOVE_ORIGIN_AND_SOURCE; |
| 2087 | else if (shift) action = MOVE_ORIGIN; |
| 2088 | else if (ctrl) action = MOVE_SOURCE; |
| 2089 | else action = MOVE_CURSOR; |
| 2090 | } else if (button == 'a' || button == 's' || button == 'd' || |
| 2091 | button == 'A' || button == 'S' || button == 'D' || |
| 2092 | button == 'f' || button == 'F' || |
| 2093 | IS_CURSOR_SELECT(button)) { |
| 2094 | tx = ui->cur_x; |
| 2095 | ty = ui->cur_y; |
| 2096 | if (button == 'a' || button == 'A' || button == CURSOR_SELECT) |
| 2097 | action = ROTATE_LEFT; |
| 2098 | else if (button == 's' || button == 'S' || button == CURSOR_SELECT2) |
| 2099 | action = TOGGLE_LOCK; |
| 2100 | else if (button == 'd' || button == 'D') |
| 2101 | action = ROTATE_RIGHT; |
| 2102 | else if (button == 'f' || button == 'F') |
| 2103 | action = ROTATE_180; |
| 2104 | ui->cur_visible = TRUE; |
| 2105 | } else if (button == 'j' || button == 'J') { |
| 2106 | /* XXX should we have some mouse control for this? */ |
| 2107 | action = JUMBLE; |
| 2108 | } else |
| 2109 | return nullret; |
| 2110 | |
| 2111 | /* |
| 2112 | * The middle button locks or unlocks a tile. (A locked tile |
| 2113 | * cannot be turned, and is visually marked as being locked. |
| 2114 | * This is a convenience for the player, so that once they are |
| 2115 | * sure which way round a tile goes, they can lock it and thus |
| 2116 | * avoid forgetting later on that they'd already done that one; |
| 2117 | * and the locking also prevents them turning the tile by |
| 2118 | * accident. If they change their mind, another middle click |
| 2119 | * unlocks it.) |
| 2120 | */ |
| 2121 | if (action == TOGGLE_LOCK) { |
| 2122 | char buf[80]; |
| 2123 | sprintf(buf, "L%d,%d", tx, ty); |
| 2124 | return dupstr(buf); |
| 2125 | } else if (action == ROTATE_LEFT || action == ROTATE_RIGHT || |
| 2126 | action == ROTATE_180) { |
| 2127 | char buf[80]; |
| 2128 | |
| 2129 | /* |
| 2130 | * The left and right buttons have no effect if clicked on a |
| 2131 | * locked tile. |
| 2132 | */ |
| 2133 | if (tile(state, tx, ty) & LOCKED) |
| 2134 | return nullret; |
| 2135 | |
| 2136 | /* |
| 2137 | * Otherwise, turn the tile one way or the other. Left button |
| 2138 | * turns anticlockwise; right button turns clockwise. |
| 2139 | */ |
| 2140 | sprintf(buf, "%c%d,%d", (int)(action == ROTATE_LEFT ? 'A' : |
| 2141 | action == ROTATE_RIGHT ? 'C' : 'F'), tx, ty); |
| 2142 | return dupstr(buf); |
| 2143 | } else if (action == JUMBLE) { |
| 2144 | /* |
| 2145 | * Jumble all unlocked tiles to random orientations. |
| 2146 | */ |
| 2147 | |
| 2148 | int jx, jy, maxlen; |
| 2149 | char *ret, *p; |
| 2150 | |
| 2151 | /* |
| 2152 | * Maximum string length assumes no int can be converted to |
| 2153 | * decimal and take more than 11 digits! |
| 2154 | */ |
| 2155 | maxlen = state->width * state->height * 25 + 3; |
| 2156 | |
| 2157 | ret = snewn(maxlen, char); |
| 2158 | p = ret; |
| 2159 | *p++ = 'J'; |
| 2160 | |
| 2161 | for (jy = 0; jy < state->height; jy++) { |
| 2162 | for (jx = 0; jx < state->width; jx++) { |
| 2163 | if (!(tile(state, jx, jy) & LOCKED)) { |
| 2164 | int rot = random_upto(ui->rs, 4); |
| 2165 | if (rot) { |
| 2166 | p += sprintf(p, ";%c%d,%d", "AFC"[rot-1], jx, jy); |
| 2167 | } |
| 2168 | } |
| 2169 | } |
| 2170 | } |
| 2171 | *p++ = '\0'; |
| 2172 | assert(p - ret < maxlen); |
| 2173 | ret = sresize(ret, p - ret, char); |
| 2174 | |
| 2175 | return ret; |
| 2176 | } else if (action == MOVE_ORIGIN || action == MOVE_SOURCE || |
| 2177 | action == MOVE_ORIGIN_AND_SOURCE || action == MOVE_CURSOR) { |
| 2178 | assert(dir != 0); |
| 2179 | if (action == MOVE_ORIGIN || action == MOVE_ORIGIN_AND_SOURCE) { |
| 2180 | if (state->wrapping) { |
| 2181 | OFFSET(ui->org_x, ui->org_y, ui->org_x, ui->org_y, dir, state); |
| 2182 | } else return nullret; /* disallowed for non-wrapping grids */ |
| 2183 | } |
| 2184 | if (action == MOVE_SOURCE || action == MOVE_ORIGIN_AND_SOURCE) { |
| 2185 | OFFSET(ui->cx, ui->cy, ui->cx, ui->cy, dir, state); |
| 2186 | } |
| 2187 | if (action == MOVE_CURSOR) { |
| 2188 | OFFSET(ui->cur_x, ui->cur_y, ui->cur_x, ui->cur_y, dir, state); |
| 2189 | ui->cur_visible = TRUE; |
| 2190 | } |
| 2191 | return ""; |
| 2192 | } else { |
| 2193 | return NULL; |
| 2194 | } |
| 2195 | } |
| 2196 | |
| 2197 | static game_state *execute_move(game_state *from, char *move) |
| 2198 | { |
| 2199 | game_state *ret; |
| 2200 | int tx = -1, ty = -1, n, noanim, orig; |
| 2201 | |
| 2202 | ret = dup_game(from); |
| 2203 | |
| 2204 | if (move[0] == 'J' || move[0] == 'S') { |
| 2205 | if (move[0] == 'S') |
| 2206 | ret->used_solve = TRUE; |
| 2207 | |
| 2208 | move++; |
| 2209 | if (*move == ';') |
| 2210 | move++; |
| 2211 | noanim = TRUE; |
| 2212 | } else |
| 2213 | noanim = FALSE; |
| 2214 | |
| 2215 | ret->last_rotate_dir = 0; /* suppress animation */ |
| 2216 | ret->last_rotate_x = ret->last_rotate_y = 0; |
| 2217 | |
| 2218 | while (*move) { |
| 2219 | if ((move[0] == 'A' || move[0] == 'C' || |
| 2220 | move[0] == 'F' || move[0] == 'L') && |
| 2221 | sscanf(move+1, "%d,%d%n", &tx, &ty, &n) >= 2 && |
| 2222 | tx >= 0 && tx < from->width && ty >= 0 && ty < from->height) { |
| 2223 | orig = tile(ret, tx, ty); |
| 2224 | if (move[0] == 'A') { |
| 2225 | tile(ret, tx, ty) = A(orig); |
| 2226 | if (!noanim) |
| 2227 | ret->last_rotate_dir = +1; |
| 2228 | } else if (move[0] == 'F') { |
| 2229 | tile(ret, tx, ty) = F(orig); |
| 2230 | if (!noanim) |
| 2231 | ret->last_rotate_dir = +2; /* + for sake of argument */ |
| 2232 | } else if (move[0] == 'C') { |
| 2233 | tile(ret, tx, ty) = C(orig); |
| 2234 | if (!noanim) |
| 2235 | ret->last_rotate_dir = -1; |
| 2236 | } else { |
| 2237 | assert(move[0] == 'L'); |
| 2238 | tile(ret, tx, ty) ^= LOCKED; |
| 2239 | } |
| 2240 | |
| 2241 | move += 1 + n; |
| 2242 | if (*move == ';') move++; |
| 2243 | } else { |
| 2244 | free_game(ret); |
| 2245 | return NULL; |
| 2246 | } |
| 2247 | } |
| 2248 | if (!noanim) { |
| 2249 | if (tx == -1 || ty == -1) { free_game(ret); return NULL; } |
| 2250 | ret->last_rotate_x = tx; |
| 2251 | ret->last_rotate_y = ty; |
| 2252 | } |
| 2253 | |
| 2254 | /* |
| 2255 | * Check whether the game has been completed. |
| 2256 | * |
| 2257 | * For this purpose it doesn't matter where the source square |
| 2258 | * is, because we can start from anywhere and correctly |
| 2259 | * determine whether the game is completed. |
| 2260 | */ |
| 2261 | { |
| 2262 | unsigned char *active = compute_active(ret, 0, 0); |
| 2263 | int x1, y1; |
| 2264 | int complete = TRUE; |
| 2265 | |
| 2266 | for (x1 = 0; x1 < ret->width; x1++) |
| 2267 | for (y1 = 0; y1 < ret->height; y1++) |
| 2268 | if ((tile(ret, x1, y1) & 0xF) && !index(ret, active, x1, y1)) { |
| 2269 | complete = FALSE; |
| 2270 | goto break_label; /* break out of two loops at once */ |
| 2271 | } |
| 2272 | break_label: |
| 2273 | |
| 2274 | sfree(active); |
| 2275 | |
| 2276 | if (complete) |
| 2277 | ret->completed = TRUE; |
| 2278 | } |
| 2279 | |
| 2280 | return ret; |
| 2281 | } |
| 2282 | |
| 2283 | |
| 2284 | /* ---------------------------------------------------------------------- |
| 2285 | * Routines for drawing the game position on the screen. |
| 2286 | */ |
| 2287 | |
| 2288 | static game_drawstate *game_new_drawstate(drawing *dr, game_state *state) |
| 2289 | { |
| 2290 | game_drawstate *ds = snew(game_drawstate); |
| 2291 | |
| 2292 | ds->started = FALSE; |
| 2293 | ds->width = state->width; |
| 2294 | ds->height = state->height; |
| 2295 | ds->org_x = ds->org_y = -1; |
| 2296 | ds->visible = snewn(state->width * state->height, unsigned char); |
| 2297 | ds->tilesize = 0; /* undecided yet */ |
| 2298 | memset(ds->visible, 0xFF, state->width * state->height); |
| 2299 | |
| 2300 | return ds; |
| 2301 | } |
| 2302 | |
| 2303 | static void game_free_drawstate(drawing *dr, game_drawstate *ds) |
| 2304 | { |
| 2305 | sfree(ds->visible); |
| 2306 | sfree(ds); |
| 2307 | } |
| 2308 | |
| 2309 | static void game_compute_size(game_params *params, int tilesize, |
| 2310 | int *x, int *y) |
| 2311 | { |
| 2312 | *x = WINDOW_OFFSET * 2 + tilesize * params->width + TILE_BORDER; |
| 2313 | *y = WINDOW_OFFSET * 2 + tilesize * params->height + TILE_BORDER; |
| 2314 | } |
| 2315 | |
| 2316 | static void game_set_size(drawing *dr, game_drawstate *ds, |
| 2317 | game_params *params, int tilesize) |
| 2318 | { |
| 2319 | ds->tilesize = tilesize; |
| 2320 | } |
| 2321 | |
| 2322 | static float *game_colours(frontend *fe, int *ncolours) |
| 2323 | { |
| 2324 | float *ret; |
| 2325 | |
| 2326 | ret = snewn(NCOLOURS * 3, float); |
| 2327 | *ncolours = NCOLOURS; |
| 2328 | |
| 2329 | /* |
| 2330 | * Basic background colour is whatever the front end thinks is |
| 2331 | * a sensible default. |
| 2332 | */ |
| 2333 | frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]); |
| 2334 | |
| 2335 | /* |
| 2336 | * Wires are black. |
| 2337 | */ |
| 2338 | ret[COL_WIRE * 3 + 0] = 0.0F; |
| 2339 | ret[COL_WIRE * 3 + 1] = 0.0F; |
| 2340 | ret[COL_WIRE * 3 + 2] = 0.0F; |
| 2341 | |
| 2342 | /* |
| 2343 | * Powered wires and powered endpoints are cyan. |
| 2344 | */ |
| 2345 | ret[COL_POWERED * 3 + 0] = 0.0F; |
| 2346 | ret[COL_POWERED * 3 + 1] = 1.0F; |
| 2347 | ret[COL_POWERED * 3 + 2] = 1.0F; |
| 2348 | |
| 2349 | /* |
| 2350 | * Barriers are red. |
| 2351 | */ |
| 2352 | ret[COL_BARRIER * 3 + 0] = 1.0F; |
| 2353 | ret[COL_BARRIER * 3 + 1] = 0.0F; |
| 2354 | ret[COL_BARRIER * 3 + 2] = 0.0F; |
| 2355 | |
| 2356 | /* |
| 2357 | * Unpowered endpoints are blue. |
| 2358 | */ |
| 2359 | ret[COL_ENDPOINT * 3 + 0] = 0.0F; |
| 2360 | ret[COL_ENDPOINT * 3 + 1] = 0.0F; |
| 2361 | ret[COL_ENDPOINT * 3 + 2] = 1.0F; |
| 2362 | |
| 2363 | /* |
| 2364 | * Tile borders are a darker grey than the background. |
| 2365 | */ |
| 2366 | ret[COL_BORDER * 3 + 0] = 0.5F * ret[COL_BACKGROUND * 3 + 0]; |
| 2367 | ret[COL_BORDER * 3 + 1] = 0.5F * ret[COL_BACKGROUND * 3 + 1]; |
| 2368 | ret[COL_BORDER * 3 + 2] = 0.5F * ret[COL_BACKGROUND * 3 + 2]; |
| 2369 | |
| 2370 | /* |
| 2371 | * Locked tiles are a grey in between those two. |
| 2372 | */ |
| 2373 | ret[COL_LOCKED * 3 + 0] = 0.75F * ret[COL_BACKGROUND * 3 + 0]; |
| 2374 | ret[COL_LOCKED * 3 + 1] = 0.75F * ret[COL_BACKGROUND * 3 + 1]; |
| 2375 | ret[COL_LOCKED * 3 + 2] = 0.75F * ret[COL_BACKGROUND * 3 + 2]; |
| 2376 | |
| 2377 | return ret; |
| 2378 | } |
| 2379 | |
| 2380 | static void draw_filled_line(drawing *dr, int x1, int y1, int x2, int y2, |
| 2381 | int colour) |
| 2382 | { |
| 2383 | draw_line(dr, x1-1, y1, x2-1, y2, COL_WIRE); |
| 2384 | draw_line(dr, x1+1, y1, x2+1, y2, COL_WIRE); |
| 2385 | draw_line(dr, x1, y1-1, x2, y2-1, COL_WIRE); |
| 2386 | draw_line(dr, x1, y1+1, x2, y2+1, COL_WIRE); |
| 2387 | draw_line(dr, x1, y1, x2, y2, colour); |
| 2388 | } |
| 2389 | |
| 2390 | static void draw_rect_coords(drawing *dr, int x1, int y1, int x2, int y2, |
| 2391 | int colour) |
| 2392 | { |
| 2393 | int mx = (x1 < x2 ? x1 : x2); |
| 2394 | int my = (y1 < y2 ? y1 : y2); |
| 2395 | int dx = (x2 + x1 - 2*mx + 1); |
| 2396 | int dy = (y2 + y1 - 2*my + 1); |
| 2397 | |
| 2398 | draw_rect(dr, mx, my, dx, dy, colour); |
| 2399 | } |
| 2400 | |
| 2401 | /* |
| 2402 | * draw_barrier_corner() and draw_barrier() are passed physical coords |
| 2403 | */ |
| 2404 | static void draw_barrier_corner(drawing *dr, game_drawstate *ds, |
| 2405 | int x, int y, int dx, int dy, int phase) |
| 2406 | { |
| 2407 | int bx = WINDOW_OFFSET + TILE_SIZE * x; |
| 2408 | int by = WINDOW_OFFSET + TILE_SIZE * y; |
| 2409 | int x1, y1; |
| 2410 | |
| 2411 | x1 = (dx > 0 ? TILE_SIZE+TILE_BORDER-1 : 0); |
| 2412 | y1 = (dy > 0 ? TILE_SIZE+TILE_BORDER-1 : 0); |
| 2413 | |
| 2414 | if (phase == 0) { |
| 2415 | draw_rect_coords(dr, bx+x1+dx, by+y1, |
| 2416 | bx+x1-TILE_BORDER*dx, by+y1-(TILE_BORDER-1)*dy, |
| 2417 | COL_WIRE); |
| 2418 | draw_rect_coords(dr, bx+x1, by+y1+dy, |
| 2419 | bx+x1-(TILE_BORDER-1)*dx, by+y1-TILE_BORDER*dy, |
| 2420 | COL_WIRE); |
| 2421 | } else { |
| 2422 | draw_rect_coords(dr, bx+x1, by+y1, |
| 2423 | bx+x1-(TILE_BORDER-1)*dx, by+y1-(TILE_BORDER-1)*dy, |
| 2424 | COL_BARRIER); |
| 2425 | } |
| 2426 | } |
| 2427 | |
| 2428 | static void draw_barrier(drawing *dr, game_drawstate *ds, |
| 2429 | int x, int y, int dir, int phase) |
| 2430 | { |
| 2431 | int bx = WINDOW_OFFSET + TILE_SIZE * x; |
| 2432 | int by = WINDOW_OFFSET + TILE_SIZE * y; |
| 2433 | int x1, y1, w, h; |
| 2434 | |
| 2435 | x1 = (X(dir) > 0 ? TILE_SIZE : X(dir) == 0 ? TILE_BORDER : 0); |
| 2436 | y1 = (Y(dir) > 0 ? TILE_SIZE : Y(dir) == 0 ? TILE_BORDER : 0); |
| 2437 | w = (X(dir) ? TILE_BORDER : TILE_SIZE - TILE_BORDER); |
| 2438 | h = (Y(dir) ? TILE_BORDER : TILE_SIZE - TILE_BORDER); |
| 2439 | |
| 2440 | if (phase == 0) { |
| 2441 | draw_rect(dr, bx+x1-X(dir), by+y1-Y(dir), w, h, COL_WIRE); |
| 2442 | } else { |
| 2443 | draw_rect(dr, bx+x1, by+y1, w, h, COL_BARRIER); |
| 2444 | } |
| 2445 | } |
| 2446 | |
| 2447 | /* |
| 2448 | * draw_tile() is passed physical coordinates |
| 2449 | */ |
| 2450 | static void draw_tile(drawing *dr, game_state *state, game_drawstate *ds, |
| 2451 | int x, int y, int tile, int src, float angle, int cursor) |
| 2452 | { |
| 2453 | int bx = WINDOW_OFFSET + TILE_SIZE * x; |
| 2454 | int by = WINDOW_OFFSET + TILE_SIZE * y; |
| 2455 | float matrix[4]; |
| 2456 | float cx, cy, ex, ey, tx, ty; |
| 2457 | int dir, col, phase; |
| 2458 | |
| 2459 | /* |
| 2460 | * When we draw a single tile, we must draw everything up to |
| 2461 | * and including the borders around the tile. This means that |
| 2462 | * if the neighbouring tiles have connections to those borders, |
| 2463 | * we must draw those connections on the borders themselves. |
| 2464 | */ |
| 2465 | |
| 2466 | clip(dr, bx, by, TILE_SIZE+TILE_BORDER, TILE_SIZE+TILE_BORDER); |
| 2467 | |
| 2468 | /* |
| 2469 | * So. First blank the tile out completely: draw a big |
| 2470 | * rectangle in border colour, and a smaller rectangle in |
| 2471 | * background colour to fill it in. |
| 2472 | */ |
| 2473 | draw_rect(dr, bx, by, TILE_SIZE+TILE_BORDER, TILE_SIZE+TILE_BORDER, |
| 2474 | COL_BORDER); |
| 2475 | draw_rect(dr, bx+TILE_BORDER, by+TILE_BORDER, |
| 2476 | TILE_SIZE-TILE_BORDER, TILE_SIZE-TILE_BORDER, |
| 2477 | tile & LOCKED ? COL_LOCKED : COL_BACKGROUND); |
| 2478 | |
| 2479 | /* |
| 2480 | * Draw an inset outline rectangle as a cursor, in whichever of |
| 2481 | * COL_LOCKED and COL_BACKGROUND we aren't currently drawing |
| 2482 | * in. |
| 2483 | */ |
| 2484 | if (cursor) { |
| 2485 | draw_line(dr, bx+TILE_SIZE/8, by+TILE_SIZE/8, |
| 2486 | bx+TILE_SIZE/8, by+TILE_SIZE-TILE_SIZE/8, |
| 2487 | tile & LOCKED ? COL_BACKGROUND : COL_LOCKED); |
| 2488 | draw_line(dr, bx+TILE_SIZE/8, by+TILE_SIZE/8, |
| 2489 | bx+TILE_SIZE-TILE_SIZE/8, by+TILE_SIZE/8, |
| 2490 | tile & LOCKED ? COL_BACKGROUND : COL_LOCKED); |
| 2491 | draw_line(dr, bx+TILE_SIZE-TILE_SIZE/8, by+TILE_SIZE/8, |
| 2492 | bx+TILE_SIZE-TILE_SIZE/8, by+TILE_SIZE-TILE_SIZE/8, |
| 2493 | tile & LOCKED ? COL_BACKGROUND : COL_LOCKED); |
| 2494 | draw_line(dr, bx+TILE_SIZE/8, by+TILE_SIZE-TILE_SIZE/8, |
| 2495 | bx+TILE_SIZE-TILE_SIZE/8, by+TILE_SIZE-TILE_SIZE/8, |
| 2496 | tile & LOCKED ? COL_BACKGROUND : COL_LOCKED); |
| 2497 | } |
| 2498 | |
| 2499 | /* |
| 2500 | * Set up the rotation matrix. |
| 2501 | */ |
| 2502 | matrix[0] = (float)cos(angle * PI / 180.0); |
| 2503 | matrix[1] = (float)-sin(angle * PI / 180.0); |
| 2504 | matrix[2] = (float)sin(angle * PI / 180.0); |
| 2505 | matrix[3] = (float)cos(angle * PI / 180.0); |
| 2506 | |
| 2507 | /* |
| 2508 | * Draw the wires. |
| 2509 | */ |
| 2510 | cx = cy = TILE_BORDER + (TILE_SIZE-TILE_BORDER) / 2.0F - 0.5F; |
| 2511 | col = (tile & ACTIVE ? COL_POWERED : COL_WIRE); |
| 2512 | for (dir = 1; dir < 0x10; dir <<= 1) { |
| 2513 | if (tile & dir) { |
| 2514 | ex = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * X(dir); |
| 2515 | ey = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * Y(dir); |
| 2516 | MATMUL(tx, ty, matrix, ex, ey); |
| 2517 | draw_filled_line(dr, bx+(int)cx, by+(int)cy, |
| 2518 | bx+(int)(cx+tx), by+(int)(cy+ty), |
| 2519 | COL_WIRE); |
| 2520 | } |
| 2521 | } |
| 2522 | for (dir = 1; dir < 0x10; dir <<= 1) { |
| 2523 | if (tile & dir) { |
| 2524 | ex = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * X(dir); |
| 2525 | ey = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * Y(dir); |
| 2526 | MATMUL(tx, ty, matrix, ex, ey); |
| 2527 | draw_line(dr, bx+(int)cx, by+(int)cy, |
| 2528 | bx+(int)(cx+tx), by+(int)(cy+ty), col); |
| 2529 | } |
| 2530 | } |
| 2531 | |
| 2532 | /* |
| 2533 | * Draw the box in the middle. We do this in blue if the tile |
| 2534 | * is an unpowered endpoint, in cyan if the tile is a powered |
| 2535 | * endpoint, in black if the tile is the centrepiece, and |
| 2536 | * otherwise not at all. |
| 2537 | */ |
| 2538 | col = -1; |
| 2539 | if (src) |
| 2540 | col = COL_WIRE; |
| 2541 | else if (COUNT(tile) == 1) { |
| 2542 | col = (tile & ACTIVE ? COL_POWERED : COL_ENDPOINT); |
| 2543 | } |
| 2544 | if (col >= 0) { |
| 2545 | int i, points[8]; |
| 2546 | |
| 2547 | points[0] = +1; points[1] = +1; |
| 2548 | points[2] = +1; points[3] = -1; |
| 2549 | points[4] = -1; points[5] = -1; |
| 2550 | points[6] = -1; points[7] = +1; |
| 2551 | |
| 2552 | for (i = 0; i < 8; i += 2) { |
| 2553 | ex = (TILE_SIZE * 0.24F) * points[i]; |
| 2554 | ey = (TILE_SIZE * 0.24F) * points[i+1]; |
| 2555 | MATMUL(tx, ty, matrix, ex, ey); |
| 2556 | points[i] = bx+(int)(cx+tx); |
| 2557 | points[i+1] = by+(int)(cy+ty); |
| 2558 | } |
| 2559 | |
| 2560 | draw_polygon(dr, points, 4, col, COL_WIRE); |
| 2561 | } |
| 2562 | |
| 2563 | /* |
| 2564 | * Draw the points on the border if other tiles are connected |
| 2565 | * to us. |
| 2566 | */ |
| 2567 | for (dir = 1; dir < 0x10; dir <<= 1) { |
| 2568 | int dx, dy, px, py, lx, ly, vx, vy, ox, oy; |
| 2569 | |
| 2570 | dx = X(dir); |
| 2571 | dy = Y(dir); |
| 2572 | |
| 2573 | ox = x + dx; |
| 2574 | oy = y + dy; |
| 2575 | |
| 2576 | if (ox < 0 || ox >= state->width || oy < 0 || oy >= state->height) |
| 2577 | continue; |
| 2578 | |
| 2579 | if (!(tile(state, GX(ox), GY(oy)) & F(dir))) |
| 2580 | continue; |
| 2581 | |
| 2582 | px = bx + (int)(dx>0 ? TILE_SIZE + TILE_BORDER - 1 : dx<0 ? 0 : cx); |
| 2583 | py = by + (int)(dy>0 ? TILE_SIZE + TILE_BORDER - 1 : dy<0 ? 0 : cy); |
| 2584 | lx = dx * (TILE_BORDER-1); |
| 2585 | ly = dy * (TILE_BORDER-1); |
| 2586 | vx = (dy ? 1 : 0); |
| 2587 | vy = (dx ? 1 : 0); |
| 2588 | |
| 2589 | if (angle == 0.0 && (tile & dir)) { |
| 2590 | /* |
| 2591 | * If we are fully connected to the other tile, we must |
| 2592 | * draw right across the tile border. (We can use our |
| 2593 | * own ACTIVE state to determine what colour to do this |
| 2594 | * in: if we are fully connected to the other tile then |
| 2595 | * the two ACTIVE states will be the same.) |
| 2596 | */ |
| 2597 | draw_rect_coords(dr, px-vx, py-vy, px+lx+vx, py+ly+vy, COL_WIRE); |
| 2598 | draw_rect_coords(dr, px, py, px+lx, py+ly, |
| 2599 | (tile & ACTIVE) ? COL_POWERED : COL_WIRE); |
| 2600 | } else { |
| 2601 | /* |
| 2602 | * The other tile extends into our border, but isn't |
| 2603 | * actually connected to us. Just draw a single black |
| 2604 | * dot. |
| 2605 | */ |
| 2606 | draw_rect_coords(dr, px, py, px, py, COL_WIRE); |
| 2607 | } |
| 2608 | } |
| 2609 | |
| 2610 | /* |
| 2611 | * Draw barrier corners, and then barriers. |
| 2612 | */ |
| 2613 | for (phase = 0; phase < 2; phase++) { |
| 2614 | for (dir = 1; dir < 0x10; dir <<= 1) { |
| 2615 | int x1, y1, corner = FALSE; |
| 2616 | /* |
| 2617 | * If at least one barrier terminates at the corner |
| 2618 | * between dir and A(dir), draw a barrier corner. |
| 2619 | */ |
| 2620 | if (barrier(state, GX(x), GY(y)) & (dir | A(dir))) { |
| 2621 | corner = TRUE; |
| 2622 | } else { |
| 2623 | /* |
| 2624 | * Only count barriers terminating at this corner |
| 2625 | * if they're physically next to the corner. (That |
| 2626 | * is, if they've wrapped round from the far side |
| 2627 | * of the screen, they don't count.) |
| 2628 | */ |
| 2629 | x1 = x + X(dir); |
| 2630 | y1 = y + Y(dir); |
| 2631 | if (x1 >= 0 && x1 < state->width && |
| 2632 | y1 >= 0 && y1 < state->height && |
| 2633 | (barrier(state, GX(x1), GY(y1)) & A(dir))) { |
| 2634 | corner = TRUE; |
| 2635 | } else { |
| 2636 | x1 = x + X(A(dir)); |
| 2637 | y1 = y + Y(A(dir)); |
| 2638 | if (x1 >= 0 && x1 < state->width && |
| 2639 | y1 >= 0 && y1 < state->height && |
| 2640 | (barrier(state, GX(x1), GY(y1)) & dir)) |
| 2641 | corner = TRUE; |
| 2642 | } |
| 2643 | } |
| 2644 | |
| 2645 | if (corner) { |
| 2646 | /* |
| 2647 | * At least one barrier terminates here. Draw a |
| 2648 | * corner. |
| 2649 | */ |
| 2650 | draw_barrier_corner(dr, ds, x, y, |
| 2651 | X(dir)+X(A(dir)), Y(dir)+Y(A(dir)), |
| 2652 | phase); |
| 2653 | } |
| 2654 | } |
| 2655 | |
| 2656 | for (dir = 1; dir < 0x10; dir <<= 1) |
| 2657 | if (barrier(state, GX(x), GY(y)) & dir) |
| 2658 | draw_barrier(dr, ds, x, y, dir, phase); |
| 2659 | } |
| 2660 | |
| 2661 | unclip(dr); |
| 2662 | |
| 2663 | draw_update(dr, bx, by, TILE_SIZE+TILE_BORDER, TILE_SIZE+TILE_BORDER); |
| 2664 | } |
| 2665 | |
| 2666 | static void game_redraw(drawing *dr, game_drawstate *ds, game_state *oldstate, |
| 2667 | game_state *state, int dir, game_ui *ui, float t, float ft) |
| 2668 | { |
| 2669 | int x, y, tx, ty, frame, last_rotate_dir, moved_origin = FALSE; |
| 2670 | unsigned char *active; |
| 2671 | float angle = 0.0; |
| 2672 | |
| 2673 | /* |
| 2674 | * Clear the screen, and draw the exterior barrier lines, if |
| 2675 | * this is our first call or if the origin has changed. |
| 2676 | */ |
| 2677 | if (!ds->started || ui->org_x != ds->org_x || ui->org_y != ds->org_y) { |
| 2678 | int phase; |
| 2679 | |
| 2680 | ds->started = TRUE; |
| 2681 | |
| 2682 | draw_rect(dr, 0, 0, |
| 2683 | WINDOW_OFFSET * 2 + TILE_SIZE * state->width + TILE_BORDER, |
| 2684 | WINDOW_OFFSET * 2 + TILE_SIZE * state->height + TILE_BORDER, |
| 2685 | COL_BACKGROUND); |
| 2686 | |
| 2687 | ds->org_x = ui->org_x; |
| 2688 | ds->org_y = ui->org_y; |
| 2689 | moved_origin = TRUE; |
| 2690 | |
| 2691 | draw_update(dr, 0, 0, |
| 2692 | WINDOW_OFFSET*2 + TILE_SIZE*state->width + TILE_BORDER, |
| 2693 | WINDOW_OFFSET*2 + TILE_SIZE*state->height + TILE_BORDER); |
| 2694 | |
| 2695 | for (phase = 0; phase < 2; phase++) { |
| 2696 | |
| 2697 | for (x = 0; x < ds->width; x++) { |
| 2698 | if (x+1 < ds->width) { |
| 2699 | if (barrier(state, GX(x), GY(0)) & R) |
| 2700 | draw_barrier_corner(dr, ds, x, -1, +1, +1, phase); |
| 2701 | if (barrier(state, GX(x), GY(ds->height-1)) & R) |
| 2702 | draw_barrier_corner(dr, ds, x, ds->height, +1, -1, phase); |
| 2703 | } |
| 2704 | if (barrier(state, GX(x), GY(0)) & U) { |
| 2705 | draw_barrier_corner(dr, ds, x, -1, -1, +1, phase); |
| 2706 | draw_barrier_corner(dr, ds, x, -1, +1, +1, phase); |
| 2707 | draw_barrier(dr, ds, x, -1, D, phase); |
| 2708 | } |
| 2709 | if (barrier(state, GX(x), GY(ds->height-1)) & D) { |
| 2710 | draw_barrier_corner(dr, ds, x, ds->height, -1, -1, phase); |
| 2711 | draw_barrier_corner(dr, ds, x, ds->height, +1, -1, phase); |
| 2712 | draw_barrier(dr, ds, x, ds->height, U, phase); |
| 2713 | } |
| 2714 | } |
| 2715 | |
| 2716 | for (y = 0; y < ds->height; y++) { |
| 2717 | if (y+1 < ds->height) { |
| 2718 | if (barrier(state, GX(0), GY(y)) & D) |
| 2719 | draw_barrier_corner(dr, ds, -1, y, +1, +1, phase); |
| 2720 | if (barrier(state, GX(ds->width-1), GY(y)) & D) |
| 2721 | draw_barrier_corner(dr, ds, ds->width, y, -1, +1, phase); |
| 2722 | } |
| 2723 | if (barrier(state, GX(0), GY(y)) & L) { |
| 2724 | draw_barrier_corner(dr, ds, -1, y, +1, -1, phase); |
| 2725 | draw_barrier_corner(dr, ds, -1, y, +1, +1, phase); |
| 2726 | draw_barrier(dr, ds, -1, y, R, phase); |
| 2727 | } |
| 2728 | if (barrier(state, GX(ds->width-1), GY(y)) & R) { |
| 2729 | draw_barrier_corner(dr, ds, ds->width, y, -1, -1, phase); |
| 2730 | draw_barrier_corner(dr, ds, ds->width, y, -1, +1, phase); |
| 2731 | draw_barrier(dr, ds, ds->width, y, L, phase); |
| 2732 | } |
| 2733 | } |
| 2734 | } |
| 2735 | } |
| 2736 | |
| 2737 | tx = ty = -1; |
| 2738 | last_rotate_dir = dir==-1 ? oldstate->last_rotate_dir : |
| 2739 | state->last_rotate_dir; |
| 2740 | if (oldstate && (t < ROTATE_TIME) && last_rotate_dir) { |
| 2741 | /* |
| 2742 | * We're animating a single tile rotation. Find the turning |
| 2743 | * tile. |
| 2744 | */ |
| 2745 | tx = (dir==-1 ? oldstate->last_rotate_x : state->last_rotate_x); |
| 2746 | ty = (dir==-1 ? oldstate->last_rotate_y : state->last_rotate_y); |
| 2747 | angle = last_rotate_dir * dir * 90.0F * (t / ROTATE_TIME); |
| 2748 | state = oldstate; |
| 2749 | } |
| 2750 | |
| 2751 | frame = -1; |
| 2752 | if (ft > 0) { |
| 2753 | /* |
| 2754 | * We're animating a completion flash. Find which frame |
| 2755 | * we're at. |
| 2756 | */ |
| 2757 | frame = (int)(ft / FLASH_FRAME); |
| 2758 | } |
| 2759 | |
| 2760 | /* |
| 2761 | * Draw any tile which differs from the way it was last drawn. |
| 2762 | */ |
| 2763 | active = compute_active(state, ui->cx, ui->cy); |
| 2764 | |
| 2765 | for (x = 0; x < ds->width; x++) |
| 2766 | for (y = 0; y < ds->height; y++) { |
| 2767 | unsigned char c = tile(state, GX(x), GY(y)) | |
| 2768 | index(state, active, GX(x), GY(y)); |
| 2769 | int is_src = GX(x) == ui->cx && GY(y) == ui->cy; |
| 2770 | int is_anim = GX(x) == tx && GY(y) == ty; |
| 2771 | int is_cursor = ui->cur_visible && |
| 2772 | GX(x) == ui->cur_x && GY(y) == ui->cur_y; |
| 2773 | |
| 2774 | /* |
| 2775 | * In a completion flash, we adjust the LOCKED bit |
| 2776 | * depending on our distance from the centre point and |
| 2777 | * the frame number. |
| 2778 | */ |
| 2779 | if (frame >= 0) { |
| 2780 | int rcx = RX(ui->cx), rcy = RY(ui->cy); |
| 2781 | int xdist, ydist, dist; |
| 2782 | xdist = (x < rcx ? rcx - x : x - rcx); |
| 2783 | ydist = (y < rcy ? rcy - y : y - rcy); |
| 2784 | dist = (xdist > ydist ? xdist : ydist); |
| 2785 | |
| 2786 | if (frame >= dist && frame < dist+4) { |
| 2787 | int lock = (frame - dist) & 1; |
| 2788 | lock = lock ? LOCKED : 0; |
| 2789 | c = (c &~ LOCKED) | lock; |
| 2790 | } |
| 2791 | } |
| 2792 | |
| 2793 | if (moved_origin || |
| 2794 | index(state, ds->visible, x, y) != c || |
| 2795 | index(state, ds->visible, x, y) == 0xFF || |
| 2796 | is_src || is_anim || is_cursor) { |
| 2797 | draw_tile(dr, state, ds, x, y, c, |
| 2798 | is_src, (is_anim ? angle : 0.0F), is_cursor); |
| 2799 | if (is_src || is_anim || is_cursor) |
| 2800 | index(state, ds->visible, x, y) = 0xFF; |
| 2801 | else |
| 2802 | index(state, ds->visible, x, y) = c; |
| 2803 | } |
| 2804 | } |
| 2805 | |
| 2806 | /* |
| 2807 | * Update the status bar. |
| 2808 | */ |
| 2809 | { |
| 2810 | char statusbuf[256]; |
| 2811 | int i, n, n2, a; |
| 2812 | |
| 2813 | n = state->width * state->height; |
| 2814 | for (i = a = n2 = 0; i < n; i++) { |
| 2815 | if (active[i]) |
| 2816 | a++; |
| 2817 | if (state->tiles[i] & 0xF) |
| 2818 | n2++; |
| 2819 | } |
| 2820 | |
| 2821 | sprintf(statusbuf, "%sActive: %d/%d", |
| 2822 | (state->used_solve ? "Auto-solved. " : |
| 2823 | state->completed ? "COMPLETED! " : ""), a, n2); |
| 2824 | |
| 2825 | status_bar(dr, statusbuf); |
| 2826 | } |
| 2827 | |
| 2828 | sfree(active); |
| 2829 | } |
| 2830 | |
| 2831 | static float game_anim_length(game_state *oldstate, |
| 2832 | game_state *newstate, int dir, game_ui *ui) |
| 2833 | { |
| 2834 | int last_rotate_dir; |
| 2835 | |
| 2836 | /* |
| 2837 | * Don't animate if last_rotate_dir is zero. |
| 2838 | */ |
| 2839 | last_rotate_dir = dir==-1 ? oldstate->last_rotate_dir : |
| 2840 | newstate->last_rotate_dir; |
| 2841 | if (last_rotate_dir) |
| 2842 | return ROTATE_TIME; |
| 2843 | |
| 2844 | return 0.0F; |
| 2845 | } |
| 2846 | |
| 2847 | static float game_flash_length(game_state *oldstate, |
| 2848 | game_state *newstate, int dir, game_ui *ui) |
| 2849 | { |
| 2850 | /* |
| 2851 | * If the game has just been completed, we display a completion |
| 2852 | * flash. |
| 2853 | */ |
| 2854 | if (!oldstate->completed && newstate->completed && |
| 2855 | !oldstate->used_solve && !newstate->used_solve) { |
| 2856 | int size = 0; |
| 2857 | if (size < newstate->width) |
| 2858 | size = newstate->width; |
| 2859 | if (size < newstate->height) |
| 2860 | size = newstate->height; |
| 2861 | return FLASH_FRAME * (size+4); |
| 2862 | } |
| 2863 | |
| 2864 | return 0.0F; |
| 2865 | } |
| 2866 | |
| 2867 | static int game_status(game_state *state) |
| 2868 | { |
| 2869 | return state->completed ? +1 : 0; |
| 2870 | } |
| 2871 | |
| 2872 | static int game_timing_state(game_state *state, game_ui *ui) |
| 2873 | { |
| 2874 | return TRUE; |
| 2875 | } |
| 2876 | |
| 2877 | static void game_print_size(game_params *params, float *x, float *y) |
| 2878 | { |
| 2879 | int pw, ph; |
| 2880 | |
| 2881 | /* |
| 2882 | * I'll use 8mm squares by default. |
| 2883 | */ |
| 2884 | game_compute_size(params, 800, &pw, &ph); |
| 2885 | *x = pw / 100.0F; |
| 2886 | *y = ph / 100.0F; |
| 2887 | } |
| 2888 | |
| 2889 | static void draw_diagram(drawing *dr, game_drawstate *ds, int x, int y, |
| 2890 | int topleft, int v, int drawlines, int ink) |
| 2891 | { |
| 2892 | int tx, ty, cx, cy, r, br, k, thick; |
| 2893 | |
| 2894 | tx = WINDOW_OFFSET + TILE_SIZE * x; |
| 2895 | ty = WINDOW_OFFSET + TILE_SIZE * y; |
| 2896 | |
| 2897 | /* |
| 2898 | * Find our centre point. |
| 2899 | */ |
| 2900 | if (topleft) { |
| 2901 | cx = tx + (v & L ? TILE_SIZE / 4 : TILE_SIZE / 6); |
| 2902 | cy = ty + (v & U ? TILE_SIZE / 4 : TILE_SIZE / 6); |
| 2903 | r = TILE_SIZE / 8; |
| 2904 | br = TILE_SIZE / 32; |
| 2905 | } else { |
| 2906 | cx = tx + TILE_SIZE / 2; |
| 2907 | cy = ty + TILE_SIZE / 2; |
| 2908 | r = TILE_SIZE / 2; |
| 2909 | br = TILE_SIZE / 8; |
| 2910 | } |
| 2911 | thick = r / 20; |
| 2912 | |
| 2913 | /* |
| 2914 | * Draw the square block if we have an endpoint. |
| 2915 | */ |
| 2916 | if (v == 1 || v == 2 || v == 4 || v == 8) |
| 2917 | draw_rect(dr, cx - br, cy - br, br*2, br*2, ink); |
| 2918 | |
| 2919 | /* |
| 2920 | * Draw each radial line. |
| 2921 | */ |
| 2922 | if (drawlines) { |
| 2923 | for (k = 1; k < 16; k *= 2) |
| 2924 | if (v & k) { |
| 2925 | int x1 = min(cx, cx + (r-thick) * X(k)); |
| 2926 | int x2 = max(cx, cx + (r-thick) * X(k)); |
| 2927 | int y1 = min(cy, cy + (r-thick) * Y(k)); |
| 2928 | int y2 = max(cy, cy + (r-thick) * Y(k)); |
| 2929 | draw_rect(dr, x1 - thick, y1 - thick, |
| 2930 | (x2 - x1) + 2*thick, (y2 - y1) + 2*thick, ink); |
| 2931 | } |
| 2932 | } |
| 2933 | } |
| 2934 | |
| 2935 | static void game_print(drawing *dr, game_state *state, int tilesize) |
| 2936 | { |
| 2937 | int w = state->width, h = state->height; |
| 2938 | int ink = print_mono_colour(dr, 0); |
| 2939 | int x, y; |
| 2940 | |
| 2941 | /* Ick: fake up `ds->tilesize' for macro expansion purposes */ |
| 2942 | game_drawstate ads, *ds = &ads; |
| 2943 | game_set_size(dr, ds, NULL, tilesize); |
| 2944 | |
| 2945 | /* |
| 2946 | * Border. |
| 2947 | */ |
| 2948 | print_line_width(dr, TILE_SIZE / (state->wrapping ? 128 : 12)); |
| 2949 | draw_rect_outline(dr, WINDOW_OFFSET, WINDOW_OFFSET, |
| 2950 | TILE_SIZE * w, TILE_SIZE * h, ink); |
| 2951 | |
| 2952 | /* |
| 2953 | * Grid. |
| 2954 | */ |
| 2955 | print_line_width(dr, TILE_SIZE / 128); |
| 2956 | for (x = 1; x < w; x++) |
| 2957 | draw_line(dr, WINDOW_OFFSET + TILE_SIZE * x, WINDOW_OFFSET, |
| 2958 | WINDOW_OFFSET + TILE_SIZE * x, WINDOW_OFFSET + TILE_SIZE * h, |
| 2959 | ink); |
| 2960 | for (y = 1; y < h; y++) |
| 2961 | draw_line(dr, WINDOW_OFFSET, WINDOW_OFFSET + TILE_SIZE * y, |
| 2962 | WINDOW_OFFSET + TILE_SIZE * w, WINDOW_OFFSET + TILE_SIZE * y, |
| 2963 | ink); |
| 2964 | |
| 2965 | /* |
| 2966 | * Barriers. |
| 2967 | */ |
| 2968 | for (y = 0; y <= h; y++) |
| 2969 | for (x = 0; x <= w; x++) { |
| 2970 | int b = barrier(state, x % w, y % h); |
| 2971 | if (x < w && (b & U)) |
| 2972 | draw_rect(dr, WINDOW_OFFSET + TILE_SIZE * x - TILE_SIZE/24, |
| 2973 | WINDOW_OFFSET + TILE_SIZE * y - TILE_SIZE/24, |
| 2974 | TILE_SIZE + TILE_SIZE/24 * 2, TILE_SIZE/24 * 2, ink); |
| 2975 | if (y < h && (b & L)) |
| 2976 | draw_rect(dr, WINDOW_OFFSET + TILE_SIZE * x - TILE_SIZE/24, |
| 2977 | WINDOW_OFFSET + TILE_SIZE * y - TILE_SIZE/24, |
| 2978 | TILE_SIZE/24 * 2, TILE_SIZE + TILE_SIZE/24 * 2, ink); |
| 2979 | } |
| 2980 | |
| 2981 | /* |
| 2982 | * Grid contents. |
| 2983 | */ |
| 2984 | for (y = 0; y < h; y++) |
| 2985 | for (x = 0; x < w; x++) { |
| 2986 | int vx, v = tile(state, x, y); |
| 2987 | int locked = v & LOCKED; |
| 2988 | |
| 2989 | v &= 0xF; |
| 2990 | |
| 2991 | /* |
| 2992 | * Rotate into a standard orientation for the top left |
| 2993 | * corner diagram. |
| 2994 | */ |
| 2995 | vx = v; |
| 2996 | while (vx != 0 && vx != 15 && vx != 1 && vx != 9 && vx != 13 && |
| 2997 | vx != 5) |
| 2998 | vx = A(vx); |
| 2999 | |
| 3000 | /* |
| 3001 | * Draw the top left corner diagram. |
| 3002 | */ |
| 3003 | draw_diagram(dr, ds, x, y, TRUE, vx, TRUE, ink); |
| 3004 | |
| 3005 | /* |
| 3006 | * Draw the real solution diagram, if we're doing so. |
| 3007 | */ |
| 3008 | draw_diagram(dr, ds, x, y, FALSE, v, locked, ink); |
| 3009 | } |
| 3010 | } |
| 3011 | |
| 3012 | #ifdef COMBINED |
| 3013 | #define thegame net |
| 3014 | #endif |
| 3015 | |
| 3016 | const struct game thegame = { |
| 3017 | "Net", "games.net", "net", |
| 3018 | default_params, |
| 3019 | game_fetch_preset, |
| 3020 | decode_params, |
| 3021 | encode_params, |
| 3022 | free_params, |
| 3023 | dup_params, |
| 3024 | TRUE, game_configure, custom_params, |
| 3025 | validate_params, |
| 3026 | new_game_desc, |
| 3027 | validate_desc, |
| 3028 | new_game, |
| 3029 | dup_game, |
| 3030 | free_game, |
| 3031 | TRUE, solve_game, |
| 3032 | FALSE, game_can_format_as_text_now, game_text_format, |
| 3033 | new_ui, |
| 3034 | free_ui, |
| 3035 | encode_ui, |
| 3036 | decode_ui, |
| 3037 | game_changed_state, |
| 3038 | interpret_move, |
| 3039 | execute_move, |
| 3040 | PREFERRED_TILE_SIZE, game_compute_size, game_set_size, |
| 3041 | game_colours, |
| 3042 | game_new_drawstate, |
| 3043 | game_free_drawstate, |
| 3044 | game_redraw, |
| 3045 | game_anim_length, |
| 3046 | game_flash_length, |
| 3047 | game_status, |
| 3048 | TRUE, FALSE, game_print_size, game_print, |
| 3049 | TRUE, /* wants_statusbar */ |
| 3050 | FALSE, game_timing_state, |
| 3051 | 0, /* flags */ |
| 3052 | }; |