15 #define MATMUL(xr,yr,m,x,y) do { \
16 float rx, ry, xx = (x), yy = (y), *mat = (m); \
17 rx = mat[0] * xx + mat[2] * yy; \
18 ry = mat[1] * xx + mat[3] * yy; \
19 (xr) = rx; (yr) = ry; \
22 /* Direction and other bitfields */
30 /* Rotations: Anticlockwise, Clockwise, Flip, general rotate */
31 #define A(x) ( (((x) & 0x07) << 1) | (((x) & 0x08) >> 3) )
32 #define C(x) ( (((x) & 0x0E) >> 1) | (((x) & 0x01) << 3) )
33 #define F(x) ( (((x) & 0x0C) >> 2) | (((x) & 0x03) << 2) )
34 #define ROT(x, n) ( ((n)&3) == 0 ? (x) : \
35 ((n)&3) == 1 ? A(x) : \
36 ((n)&3) == 2 ? F(x) : C(x) )
38 /* X and Y displacements */
39 #define X(x) ( (x) == R ? +1 : (x) == L ? -1 : 0 )
40 #define Y(x) ( (x) == D ? +1 : (x) == U ? -1 : 0 )
43 #define COUNT(x) ( (((x) & 0x08) >> 3) + (((x) & 0x04) >> 2) + \
44 (((x) & 0x02) >> 1) + ((x) & 0x01) )
46 #define PREFERRED_TILE_SIZE 32
47 #define TILE_SIZE (ds->tilesize)
49 #define WINDOW_OFFSET 16
51 #define ROTATE_TIME 0.13F
52 #define FLASH_FRAME 0.07F
54 /* Transform physical coords to game coords using game_drawstate ds */
55 #define GX(x) (((x) + ds->org_x) % ds->width)
56 #define GY(y) (((y) + ds->org_y) % ds->height)
57 /* ...and game coords to physical coords */
58 #define RX(x) (((x) + ds->width - ds->org_x) % ds->width)
59 #define RY(y) (((y) + ds->height - ds->org_y) % ds->height)
77 float barrier_probability;
81 int width, height, wrapping, completed;
82 int last_rotate_x, last_rotate_y, last_rotate_dir;
83 int used_solve, just_used_solve;
85 unsigned char *barriers;
88 #define OFFSETWH(x2,y2,x1,y1,dir,width,height) \
89 ( (x2) = ((x1) + width + X((dir))) % width, \
90 (y2) = ((y1) + height + Y((dir))) % height)
92 #define OFFSET(x2,y2,x1,y1,dir,state) \
93 OFFSETWH(x2,y2,x1,y1,dir,(state)->width,(state)->height)
95 #define index(state, a, x, y) ( a[(y) * (state)->width + (x)] )
96 #define tile(state, x, y) index(state, (state)->tiles, x, y)
97 #define barrier(state, x, y) index(state, (state)->barriers, x, y)
103 static int xyd_cmp(const void *av, const void *bv) {
104 const struct xyd *a = (const struct xyd *)av;
105 const struct xyd *b = (const struct xyd *)bv;
114 if (a->direction < b->direction)
116 if (a->direction > b->direction)
121 static int xyd_cmp_nc(void *av, void *bv) { return xyd_cmp(av, bv); }
123 static struct xyd *new_xyd(int x, int y, int direction)
125 struct xyd *xyd = snew(struct xyd);
128 xyd->direction = direction;
132 /* ----------------------------------------------------------------------
133 * Manage game parameters.
135 static game_params *default_params(void)
137 game_params *ret = snew(game_params);
141 ret->wrapping = FALSE;
143 ret->barrier_probability = 0.0;
148 static const struct game_params net_presets[] = {
149 {5, 5, FALSE, TRUE, 0.0},
150 {7, 7, FALSE, TRUE, 0.0},
151 {9, 9, FALSE, TRUE, 0.0},
152 {11, 11, FALSE, TRUE, 0.0},
153 {13, 11, FALSE, TRUE, 0.0},
154 {5, 5, TRUE, TRUE, 0.0},
155 {7, 7, TRUE, TRUE, 0.0},
156 {9, 9, TRUE, TRUE, 0.0},
157 {11, 11, TRUE, TRUE, 0.0},
158 {13, 11, TRUE, TRUE, 0.0},
161 static int game_fetch_preset(int i, char **name, game_params **params)
166 if (i < 0 || i >= lenof(net_presets))
169 ret = snew(game_params);
170 *ret = net_presets[i];
172 sprintf(str, "%dx%d%s", ret->width, ret->height,
173 ret->wrapping ? " wrapping" : "");
180 static void free_params(game_params *params)
185 static game_params *dup_params(game_params *params)
187 game_params *ret = snew(game_params);
188 *ret = *params; /* structure copy */
192 static void decode_params(game_params *ret, char const *string)
194 char const *p = string;
196 ret->width = atoi(p);
197 while (*p && isdigit((unsigned char)*p)) p++;
200 ret->height = atoi(p);
201 while (*p && isdigit((unsigned char)*p)) p++;
203 ret->height = ret->width;
209 ret->wrapping = TRUE;
210 } else if (*p == 'b') {
212 ret->barrier_probability = atof(p);
213 while (*p && (*p == '.' || isdigit((unsigned char)*p))) p++;
214 } else if (*p == 'a') {
218 p++; /* skip any other gunk */
222 static char *encode_params(game_params *params, int full)
227 len = sprintf(ret, "%dx%d", params->width, params->height);
228 if (params->wrapping)
230 if (full && params->barrier_probability)
231 len += sprintf(ret+len, "b%g", params->barrier_probability);
232 if (full && !params->unique)
234 assert(len < lenof(ret));
240 static config_item *game_configure(game_params *params)
245 ret = snewn(6, config_item);
247 ret[0].name = "Width";
248 ret[0].type = C_STRING;
249 sprintf(buf, "%d", params->width);
250 ret[0].sval = dupstr(buf);
253 ret[1].name = "Height";
254 ret[1].type = C_STRING;
255 sprintf(buf, "%d", params->height);
256 ret[1].sval = dupstr(buf);
259 ret[2].name = "Walls wrap around";
260 ret[2].type = C_BOOLEAN;
262 ret[2].ival = params->wrapping;
264 ret[3].name = "Barrier probability";
265 ret[3].type = C_STRING;
266 sprintf(buf, "%g", params->barrier_probability);
267 ret[3].sval = dupstr(buf);
270 ret[4].name = "Ensure unique solution";
271 ret[4].type = C_BOOLEAN;
273 ret[4].ival = params->unique;
283 static game_params *custom_params(config_item *cfg)
285 game_params *ret = snew(game_params);
287 ret->width = atoi(cfg[0].sval);
288 ret->height = atoi(cfg[1].sval);
289 ret->wrapping = cfg[2].ival;
290 ret->barrier_probability = (float)atof(cfg[3].sval);
291 ret->unique = cfg[4].ival;
296 static char *validate_params(game_params *params, int full)
298 if (params->width <= 0 || params->height <= 0)
299 return "Width and height must both be greater than zero";
300 if (params->width <= 1 && params->height <= 1)
301 return "At least one of width and height must be greater than one";
302 if (params->barrier_probability < 0)
303 return "Barrier probability may not be negative";
304 if (params->barrier_probability > 1)
305 return "Barrier probability may not be greater than 1";
308 * Specifying either grid dimension as 2 in a wrapping puzzle
309 * makes it actually impossible to ensure a unique puzzle
314 * Without loss of generality, let us assume the puzzle _width_
315 * is 2, so we can conveniently discuss rows without having to
316 * say `rows/columns' all the time. (The height may be 2 as
317 * well, but that doesn't matter.)
319 * In each row, there are two edges between tiles: the inner
320 * edge (running down the centre of the grid) and the outer
321 * edge (the identified left and right edges of the grid).
323 * Lemma: In any valid 2xn puzzle there must be at least one
324 * row in which _exactly one_ of the inner edge and outer edge
327 * Proof: No row can have _both_ inner and outer edges
328 * connected, because this would yield a loop. So the only
329 * other way to falsify the lemma is for every row to have
330 * _neither_ the inner nor outer edge connected. But this
331 * means there is no connection at all between the left and
332 * right columns of the puzzle, so there are two disjoint
333 * subgraphs, which is also disallowed. []
335 * Given such a row, it is always possible to make the
336 * disconnected edge connected and the connected edge
337 * disconnected without changing the state of any other edge.
338 * (This is easily seen by case analysis on the various tiles:
339 * left-pointing and right-pointing endpoints can be exchanged,
340 * likewise T-pieces, and a corner piece can select its
341 * horizontal connectivity independently of its vertical.) This
342 * yields a distinct valid solution.
344 * Thus, for _every_ row in which exactly one of the inner and
345 * outer edge is connected, there are two valid states for that
346 * row, and hence the total number of solutions of the puzzle
347 * is at least 2^(number of such rows), and in particular is at
348 * least 2 since there must be at least one such row. []
350 if (full && params->unique && params->wrapping &&
351 (params->width == 2 || params->height == 2))
352 return "No wrapping puzzle with a width or height of 2 can have"
353 " a unique solution";
358 /* ----------------------------------------------------------------------
359 * Solver used to assure solution uniqueness during generation.
363 * Test cases I used while debugging all this were
365 * ./net --generate 1 13x11w#12300
366 * which expands under the non-unique grid generation rules to
367 * 13x11w:5eaade1bd222664436d5e2965c12656b1129dd825219e3274d558d5eb2dab5da18898e571d5a2987be79746bd95726c597447d6da96188c513add829da7681da954db113d3cd244
368 * and has two ambiguous areas.
370 * An even better one is
371 * 13x11w#507896411361192
373 * 13x11w:b7125b1aec598eb31bd58d82572bc11494e5dee4e8db2bdd29b88d41a16bdd996d2996ddec8c83741a1e8674e78328ba71737b8894a9271b1cd1399453d1952e43951d9b712822e
374 * and has an ambiguous area _and_ a situation where loop avoidance
375 * is a necessary deductive technique.
378 * 48x25w#820543338195187
380 * 48x25w:255989d14cdd185deaa753a93821a12edc1ab97943ac127e2685d7b8b3c48861b2192416139212b316eddd35de43714ebc7628d753db32e596284d9ec52c5a7dc1b4c811a655117d16dc28921b2b4161352cab1d89d18bc836b8b891d55ea4622a1251861b5bc9a8aa3e5bcd745c95229ca6c3b5e21d5832d397e917325793d7eb442dc351b2db2a52ba8e1651642275842d8871d5534aabc6d5b741aaa2d48ed2a7dbbb3151ddb49d5b9a7ed1ab98ee75d613d656dbba347bc514c84556b43a9bc65a3256ead792488b862a9d2a8a39b4255a4949ed7dbd79443292521265896b4399c95ede89d7c8c797a6a57791a849adea489359a158aa12e5dacce862b8333b7ebea7d344d1a3c53198864b73a9dedde7b663abb1b539e1e8853b1b7edb14a2a17ebaae4dbe63598a2e7e9a2dbdad415bc1d8cb88cbab5a8c82925732cd282e641ea3bd7d2c6e776de9117a26be86deb7c82c89524b122cb9397cd1acd2284e744ea62b9279bae85479ababe315c3ac29c431333395b24e6a1e3c43a2da42d4dce84aadd5b154aea555eaddcbd6e527d228c19388d9b424d94214555a7edbdeebe569d4a56dc51a86bd9963e377bb74752bd5eaa5761ba545e297b62a1bda46ab4aee423ad6c661311783cc18786d4289236563cb4a75ec67d481c14814994464cd1b87396dee63e5ab6e952cc584baa1d4c47cb557ec84dbb63d487c8728118673a166846dd3a4ebc23d6cb9c5827d96b4556e91899db32b517eda815ae271a8911bd745447121dc8d321557bc2a435ebec1bbac35b1a291669451174e6aa2218a4a9c5a6ca31ebc45d84e3a82c121e9ced7d55e9a
381 * which has a spot (far right) where slightly more complex loop
382 * avoidance is required.
385 static int dsf_canonify(int *dsf, int val)
389 while (dsf[val] != val)
401 static void dsf_merge(int *dsf, int v1, int v2)
403 v1 = dsf_canonify(dsf, v1);
404 v2 = dsf_canonify(dsf, v2);
409 unsigned char *marked;
415 static struct todo *todo_new(int maxsize)
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;
426 static void todo_free(struct todo *todo)
433 static void todo_add(struct todo *todo, int index)
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)
443 static int todo_get(struct todo *todo) {
446 if (todo->head == todo->tail)
447 return -1; /* list is empty */
448 ret = todo->buffer[todo->head++];
449 if (todo->head == todo->buflen)
451 todo->marked[ret] = FALSE;
456 static int net_solver(int w, int h, unsigned char *tiles,
457 unsigned char *barriers, int wrapping)
459 unsigned char *tilestate;
460 unsigned char *edgestate;
469 * Set up the solver's data structures.
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.
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.)
485 tilestate = snewn(w * h * 4, unsigned char);
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;
494 tilestate[i * 4 + j] = A(tilestate[i * 4 + j - 1]);
501 * edgestate stores the known state of each edge. It is 0 for
502 * unknown, 1 for open (connected) and 2 for closed (not
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.
512 edgestate = snewn((w * h - 1) * 5 + 9, unsigned char);
513 memset(edgestate, 0, (w * h - 1) * 5 + 9);
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).
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;
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
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.
547 equivalence = snewn(w * h, int);
548 for (i = 0; i < w*h; i++)
549 equivalence[i] = i; /* initially all distinct */
552 * On a non-wrapping grid, we instantly know that all the edges
553 * round the edge are closed.
556 for (i = 0; i < w; i++) {
557 edgestate[i * 5 + 2] = edgestate[((h-1) * w + i) * 5 + 8] = 2;
559 for (i = 0; i < h; i++) {
560 edgestate[(i * w + w-1) * 5 + 1] = edgestate[(i * w) * 5 + 4] = 2;
565 * If we have barriers available, we can mark those edges as
569 for (y = 0; y < h; y++) for (x = 0; x < w; x++) {
571 for (d = 1; d <= 8; d += d) {
572 if (barriers[y*w+x] & d) {
575 * In principle the barrier list should already
576 * contain each barrier from each side, but
577 * let's not take chances with our internal
580 OFFSETWH(x2, y2, x, y, d, w, h);
581 edgestate[(y*w+x) * 5 + d] = 2;
582 edgestate[(y2*w+x2) * 5 + F(d)] = 2;
589 * Since most deductions made by this solver are local (the
590 * exception is loop avoidance, where joining two tiles
591 * together on one side of the grid can theoretically permit a
592 * fresh deduction on the other), we can address the scaling
593 * problem inherent in iterating repeatedly over the entire
594 * grid by instead working with a to-do list.
596 todo = todo_new(w * h);
599 * Main deductive loop.
601 done_something = TRUE; /* prevent instant termination! */
606 * Take a tile index off the todo list and process it.
608 index = todo_get(todo);
611 * If we have run out of immediate things to do, we
612 * have no choice but to scan the whole grid for
613 * longer-range things we've missed. Hence, I now add
614 * every square on the grid back on to the to-do list.
615 * I also set `done_something' to FALSE at this point;
616 * if we later come back here and find it still FALSE,
617 * we will know we've scanned the entire grid without
618 * finding anything new to do, and we can terminate.
622 for (i = 0; i < w*h; i++)
624 done_something = FALSE;
626 index = todo_get(todo);
632 int d, ourclass = dsf_canonify(equivalence, y*w+x);
635 deadendmax[1] = deadendmax[2] = deadendmax[4] = deadendmax[8] = 0;
637 for (i = j = 0; i < 4 && tilestate[(y*w+x) * 4 + i] != 255; i++) {
639 int nnondeadends, nondeadends[4], deadendtotal;
640 int nequiv, equiv[5];
641 int val = tilestate[(y*w+x) * 4 + i];
644 nnondeadends = deadendtotal = 0;
647 for (d = 1; d <= 8; d += d) {
649 * Immediately rule out this orientation if it
650 * conflicts with any known edge.
652 if ((edgestate[(y*w+x) * 5 + d] == 1 && !(val & d)) ||
653 (edgestate[(y*w+x) * 5 + d] == 2 && (val & d)))
658 * Count up the dead-end statistics.
660 if (deadends[(y*w+x) * 5 + d] <= area) {
661 deadendtotal += deadends[(y*w+x) * 5 + d];
663 nondeadends[nnondeadends++] = d;
667 * Ensure we aren't linking to any tiles,
668 * through edges not already known to be
669 * open, which create a loop.
671 if (edgestate[(y*w+x) * 5 + d] == 0) {
674 OFFSETWH(x2, y2, x, y, d, w, h);
675 c = dsf_canonify(equivalence, y2*w+x2);
676 for (k = 0; k < nequiv; k++)
687 if (nnondeadends == 0) {
689 * If this orientation links together dead-ends
690 * with a total area of less than the entire
691 * grid, it is invalid.
693 * (We add 1 to deadendtotal because of the
694 * tile itself, of course; one tile linking
695 * dead ends of size 2 and 3 forms a subnetwork
696 * with a total area of 6, not 5.)
698 if (deadendtotal > 0 && deadendtotal+1 < area)
700 } else if (nnondeadends == 1) {
702 * If this orientation links together one or
703 * more dead-ends with precisely one
704 * non-dead-end, then we may have to mark that
705 * non-dead-end as a dead end going the other
706 * way. However, it depends on whether all
707 * other orientations share the same property.
710 if (deadendmax[nondeadends[0]] < deadendtotal)
711 deadendmax[nondeadends[0]] = deadendtotal;
714 * If this orientation links together two or
715 * more non-dead-ends, then we can rule out the
716 * possibility of putting in new dead-end
717 * markings in those directions.
720 for (k = 0; k < nnondeadends; k++)
721 deadendmax[nondeadends[k]] = area+1;
725 tilestate[(y*w+x) * 4 + j++] = val;
726 #ifdef SOLVER_DIAGNOSTICS
728 printf("ruling out orientation %x at %d,%d\n", val, x, y);
732 assert(j > 0); /* we can't lose _all_ possibilities! */
735 done_something = TRUE;
738 * We have ruled out at least one tile orientation.
739 * Make sure the rest are blanked.
742 tilestate[(y*w+x) * 4 + j++] = 255;
746 * Now go through the tile orientations again and see
747 * if we've deduced anything new about any edges.
753 for (i = 0; i < 4 && tilestate[(y*w+x) * 4 + i] != 255; i++) {
754 a &= tilestate[(y*w+x) * 4 + i];
755 o |= tilestate[(y*w+x) * 4 + i];
757 for (d = 1; d <= 8; d += d)
758 if (edgestate[(y*w+x) * 5 + d] == 0) {
760 OFFSETWH(x2, y2, x, y, d, w, h);
763 /* This edge is open in all orientations. */
764 #ifdef SOLVER_DIAGNOSTICS
765 printf("marking edge %d,%d:%d open\n", x, y, d);
767 edgestate[(y*w+x) * 5 + d] = 1;
768 edgestate[(y2*w+x2) * 5 + d2] = 1;
769 dsf_merge(equivalence, y*w+x, y2*w+x2);
770 done_something = TRUE;
771 todo_add(todo, y2*w+x2);
772 } else if (!(o & d)) {
773 /* This edge is closed in all orientations. */
774 #ifdef SOLVER_DIAGNOSTICS
775 printf("marking edge %d,%d:%d closed\n", x, y, d);
777 edgestate[(y*w+x) * 5 + d] = 2;
778 edgestate[(y2*w+x2) * 5 + d2] = 2;
779 done_something = TRUE;
780 todo_add(todo, y2*w+x2);
787 * Now check the dead-end markers and see if any of
788 * them has lowered from the real ones.
790 for (d = 1; d <= 8; d += d) {
792 OFFSETWH(x2, y2, x, y, d, w, h);
794 if (deadendmax[d] > 0 &&
795 deadends[(y2*w+x2) * 5 + d2] > deadendmax[d]) {
796 #ifdef SOLVER_DIAGNOSTICS
797 printf("setting dead end value %d,%d:%d to %d\n",
798 x2, y2, d2, deadendmax[d]);
800 deadends[(y2*w+x2) * 5 + d2] = deadendmax[d];
801 done_something = TRUE;
802 todo_add(todo, y2*w+x2);
810 * Mark all completely determined tiles as locked.
813 for (i = 0; i < w*h; i++) {
814 if (tilestate[i * 4 + 1] == 255) {
815 assert(tilestate[i * 4 + 0] != 255);
816 tiles[i] = tilestate[i * 4] | LOCKED;
824 * Free up working space.
835 /* ----------------------------------------------------------------------
836 * Randomly select a new game description.
840 * Function to randomly perturb an ambiguous section in a grid, to
841 * attempt to ensure unique solvability.
843 static void perturb(int w, int h, unsigned char *tiles, int wrapping,
844 random_state *rs, int startx, int starty, int startd)
846 struct xyd *perimeter, *perim2, *loop[2], looppos[2];
847 int nperim, perimsize, nloop[2], loopsize[2];
851 * We know that the tile at (startx,starty) is part of an
852 * ambiguous section, and we also know that its neighbour in
853 * direction startd is fully specified. We begin by tracing all
854 * the way round the ambiguous area.
856 nperim = perimsize = 0;
861 #ifdef PERTURB_DIAGNOSTICS
862 printf("perturb %d,%d:%d\n", x, y, d);
867 if (nperim >= perimsize) {
868 perimsize = perimsize * 3 / 2 + 32;
869 perimeter = sresize(perimeter, perimsize, struct xyd);
871 perimeter[nperim].x = x;
872 perimeter[nperim].y = y;
873 perimeter[nperim].direction = d;
875 #ifdef PERTURB_DIAGNOSTICS
876 printf("perimeter: %d,%d:%d\n", x, y, d);
880 * First, see if we can simply turn left from where we are
881 * and find another locked square.
884 OFFSETWH(x2, y2, x, y, d2, w, h);
885 if ((!wrapping && (abs(x2-x) > 1 || abs(y2-y) > 1)) ||
886 (tiles[y2*w+x2] & LOCKED)) {
890 * Failing that, step left into the new square and look
895 OFFSETWH(x2, y2, x, y, d, w, h);
896 if ((wrapping || (abs(x2-x) <= 1 && abs(y2-y) <= 1)) &&
897 !(tiles[y2*w+x2] & LOCKED)) {
899 * And failing _that_, we're going to have to step
900 * forward into _that_ square and look right at the
901 * same locked square as we started with.
909 } while (x != startx || y != starty || d != startd);
912 * Our technique for perturbing this ambiguous area is to
913 * search round its edge for a join we can make: that is, an
914 * edge on the perimeter which is (a) not currently connected,
915 * and (b) connecting it would not yield a full cross on either
916 * side. Then we make that join, search round the network to
917 * find the loop thus constructed, and sever the loop at a
918 * randomly selected other point.
920 perim2 = snewn(nperim, struct xyd);
921 memcpy(perim2, perimeter, nperim * sizeof(struct xyd));
922 /* Shuffle the perimeter, so as to search it without directional bias. */
923 for (i = nperim; --i ;) {
924 int j = random_upto(rs, i+1);
928 perim2[j] = perim2[i];
931 for (i = 0; i < nperim; i++) {
936 d = perim2[i].direction;
938 OFFSETWH(x2, y2, x, y, d, w, h);
939 if (!wrapping && (abs(x2-x) > 1 || abs(y2-y) > 1))
940 continue; /* can't link across non-wrapping border */
941 if (tiles[y*w+x] & d)
942 continue; /* already linked in this direction! */
943 if (((tiles[y*w+x] | d) & 15) == 15)
944 continue; /* can't turn this tile into a cross */
945 if (((tiles[y2*w+x2] | F(d)) & 15) == 15)
946 continue; /* can't turn other tile into a cross */
949 * We've found the point at which we're going to make a new
952 #ifdef PERTURB_DIAGNOSTICS
953 printf("linking %d,%d:%d\n", x, y, d);
956 tiles[y2*w+x2] |= F(d);
963 return; /* nothing we can do! */
966 * Now we've constructed a new link, we need to find the entire
967 * loop of which it is a part.
969 * In principle, this involves doing a complete search round
970 * the network. However, I anticipate that in the vast majority
971 * of cases the loop will be quite small, so what I'm going to
972 * do is make _two_ searches round the network in parallel, one
973 * keeping its metaphorical hand on the left-hand wall while
974 * the other keeps its hand on the right. As soon as one of
975 * them gets back to its starting point, I abandon the other.
977 for (i = 0; i < 2; i++) {
978 loopsize[i] = nloop[i] = 0;
982 looppos[i].direction = d;
985 for (i = 0; i < 2; i++) {
990 d = looppos[i].direction;
992 OFFSETWH(x2, y2, x, y, d, w, h);
995 * Add this path segment to the loop, unless it exactly
996 * reverses the previous one on the loop in which case
997 * we take it away again.
999 #ifdef PERTURB_DIAGNOSTICS
1000 printf("looppos[%d] = %d,%d:%d\n", i, x, y, d);
1003 loop[i][nloop[i]-1].x == x2 &&
1004 loop[i][nloop[i]-1].y == y2 &&
1005 loop[i][nloop[i]-1].direction == F(d)) {
1006 #ifdef PERTURB_DIAGNOSTICS
1007 printf("removing path segment %d,%d:%d from loop[%d]\n",
1012 if (nloop[i] >= loopsize[i]) {
1013 loopsize[i] = loopsize[i] * 3 / 2 + 32;
1014 loop[i] = sresize(loop[i], loopsize[i], struct xyd);
1016 #ifdef PERTURB_DIAGNOSTICS
1017 printf("adding path segment %d,%d:%d to loop[%d]\n",
1020 loop[i][nloop[i]++] = looppos[i];
1023 #ifdef PERTURB_DIAGNOSTICS
1024 printf("tile at new location is %x\n", tiles[y2*w+x2] & 0xF);
1027 for (j = 0; j < 4; j++) {
1032 #ifdef PERTURB_DIAGNOSTICS
1033 printf("trying dir %d\n", d);
1035 if (tiles[y2*w+x2] & d) {
1038 looppos[i].direction = d;
1044 assert(nloop[i] > 0);
1046 if (looppos[i].x == loop[i][0].x &&
1047 looppos[i].y == loop[i][0].y &&
1048 looppos[i].direction == loop[i][0].direction) {
1049 #ifdef PERTURB_DIAGNOSTICS
1050 printf("loop %d finished tracking\n", i);
1054 * Having found our loop, we now sever it at a
1055 * randomly chosen point - absolutely any will do -
1056 * which is not the one we joined it at to begin
1057 * with. Conveniently, the one we joined it at is
1058 * loop[i][0], so we just avoid that one.
1060 j = random_upto(rs, nloop[i]-1) + 1;
1063 d = loop[i][j].direction;
1064 OFFSETWH(x2, y2, x, y, d, w, h);
1066 tiles[y2*w+x2] &= ~F(d);
1078 * Finally, we must mark the entire disputed section as locked,
1079 * to prevent the perturb function being called on it multiple
1082 * To do this, we _sort_ the perimeter of the area. The
1083 * existing xyd_cmp function will arrange things into columns
1084 * for us, in such a way that each column has the edges in
1085 * vertical order. Then we can work down each column and fill
1086 * in all the squares between an up edge and a down edge.
1088 qsort(perimeter, nperim, sizeof(struct xyd), xyd_cmp);
1090 for (i = 0; i <= nperim; i++) {
1091 if (i == nperim || perimeter[i].x > x) {
1093 * Fill in everything from the last Up edge to the
1094 * bottom of the grid, if necessary.
1098 #ifdef PERTURB_DIAGNOSTICS
1099 printf("resolved: locking tile %d,%d\n", x, y);
1101 tiles[y * w + x] |= LOCKED;
1114 if (perimeter[i].direction == U) {
1117 } else if (perimeter[i].direction == D) {
1119 * Fill in everything from the last Up edge to here.
1121 assert(x == perimeter[i].x && y <= perimeter[i].y);
1122 while (y <= perimeter[i].y) {
1123 #ifdef PERTURB_DIAGNOSTICS
1124 printf("resolved: locking tile %d,%d\n", x, y);
1126 tiles[y * w + x] |= LOCKED;
1136 static char *new_game_desc(game_params *params, random_state *rs,
1137 char **aux, int interactive)
1139 tree234 *possibilities, *barriertree;
1140 int w, h, x, y, cx, cy, nbarriers;
1141 unsigned char *tiles, *barriers;
1150 tiles = snewn(w * h, unsigned char);
1151 barriers = snewn(w * h, unsigned char);
1155 memset(tiles, 0, w * h);
1156 memset(barriers, 0, w * h);
1159 * Construct the unshuffled grid.
1161 * To do this, we simply start at the centre point, repeatedly
1162 * choose a random possibility out of the available ways to
1163 * extend a used square into an unused one, and do it. After
1164 * extending the third line out of a square, we remove the
1165 * fourth from the possibilities list to avoid any full-cross
1166 * squares (which would make the game too easy because they
1167 * only have one orientation).
1169 * The slightly worrying thing is the avoidance of full-cross
1170 * squares. Can this cause our unsophisticated construction
1171 * algorithm to paint itself into a corner, by getting into a
1172 * situation where there are some unreached squares and the
1173 * only way to reach any of them is to extend a T-piece into a
1176 * Answer: no it can't, and here's a proof.
1178 * Any contiguous group of such unreachable squares must be
1179 * surrounded on _all_ sides by T-pieces pointing away from the
1180 * group. (If not, then there is a square which can be extended
1181 * into one of the `unreachable' ones, and so it wasn't
1182 * unreachable after all.) In particular, this implies that
1183 * each contiguous group of unreachable squares must be
1184 * rectangular in shape (any deviation from that yields a
1185 * non-T-piece next to an `unreachable' square).
1187 * So we have a rectangle of unreachable squares, with T-pieces
1188 * forming a solid border around the rectangle. The corners of
1189 * that border must be connected (since every tile connects all
1190 * the lines arriving in it), and therefore the border must
1191 * form a closed loop around the rectangle.
1193 * But this can't have happened in the first place, since we
1194 * _know_ we've avoided creating closed loops! Hence, no such
1195 * situation can ever arise, and the naive grid construction
1196 * algorithm will guaranteeably result in a complete grid
1197 * containing no unreached squares, no full crosses _and_ no
1200 possibilities = newtree234(xyd_cmp_nc);
1203 add234(possibilities, new_xyd(cx, cy, R));
1205 add234(possibilities, new_xyd(cx, cy, U));
1207 add234(possibilities, new_xyd(cx, cy, L));
1209 add234(possibilities, new_xyd(cx, cy, D));
1211 while (count234(possibilities) > 0) {
1214 int x1, y1, d1, x2, y2, d2, d;
1217 * Extract a randomly chosen possibility from the list.
1219 i = random_upto(rs, count234(possibilities));
1220 xyd = delpos234(possibilities, i);
1223 d1 = xyd->direction;
1226 OFFSET(x2, y2, x1, y1, d1, params);
1228 #ifdef GENERATION_DIAGNOSTICS
1229 printf("picked (%d,%d,%c) <-> (%d,%d,%c)\n",
1230 x1, y1, "0RU3L567D9abcdef"[d1], x2, y2, "0RU3L567D9abcdef"[d2]);
1234 * Make the connection. (We should be moving to an as yet
1237 index(params, tiles, x1, y1) |= d1;
1238 assert(index(params, tiles, x2, y2) == 0);
1239 index(params, tiles, x2, y2) |= d2;
1242 * If we have created a T-piece, remove its last
1245 if (COUNT(index(params, tiles, x1, y1)) == 3) {
1246 struct xyd xyd1, *xydp;
1250 xyd1.direction = 0x0F ^ index(params, tiles, x1, y1);
1252 xydp = find234(possibilities, &xyd1, NULL);
1255 #ifdef GENERATION_DIAGNOSTICS
1256 printf("T-piece; removing (%d,%d,%c)\n",
1257 xydp->x, xydp->y, "0RU3L567D9abcdef"[xydp->direction]);
1259 del234(possibilities, xydp);
1265 * Remove all other possibilities that were pointing at the
1266 * tile we've just moved into.
1268 for (d = 1; d < 0x10; d <<= 1) {
1270 struct xyd xyd1, *xydp;
1272 OFFSET(x3, y3, x2, y2, d, params);
1277 xyd1.direction = d3;
1279 xydp = find234(possibilities, &xyd1, NULL);
1282 #ifdef GENERATION_DIAGNOSTICS
1283 printf("Loop avoidance; removing (%d,%d,%c)\n",
1284 xydp->x, xydp->y, "0RU3L567D9abcdef"[xydp->direction]);
1286 del234(possibilities, xydp);
1292 * Add new possibilities to the list for moving _out_ of
1293 * the tile we have just moved into.
1295 for (d = 1; d < 0x10; d <<= 1) {
1299 continue; /* we've got this one already */
1301 if (!params->wrapping) {
1302 if (d == U && y2 == 0)
1304 if (d == D && y2 == h-1)
1306 if (d == L && x2 == 0)
1308 if (d == R && x2 == w-1)
1312 OFFSET(x3, y3, x2, y2, d, params);
1314 if (index(params, tiles, x3, y3))
1315 continue; /* this would create a loop */
1317 #ifdef GENERATION_DIAGNOSTICS
1318 printf("New frontier; adding (%d,%d,%c)\n",
1319 x2, y2, "0RU3L567D9abcdef"[d]);
1321 add234(possibilities, new_xyd(x2, y2, d));
1324 /* Having done that, we should have no possibilities remaining. */
1325 assert(count234(possibilities) == 0);
1326 freetree234(possibilities);
1328 if (params->unique) {
1332 * Run the solver to check unique solubility.
1334 while (!net_solver(w, h, tiles, NULL, params->wrapping)) {
1338 * We expect (in most cases) that most of the grid will
1339 * be uniquely specified already, and the remaining
1340 * ambiguous sections will be small and separate. So
1341 * our strategy is to find each individual such
1342 * section, and perform a perturbation on the network
1345 for (y = 0; y < h; y++) for (x = 0; x < w; x++) {
1346 if (x+1 < w && ((tiles[y*w+x] ^ tiles[y*w+x+1]) & LOCKED)) {
1348 if (tiles[y*w+x] & LOCKED)
1349 perturb(w, h, tiles, params->wrapping, rs, x+1, y, L);
1351 perturb(w, h, tiles, params->wrapping, rs, x, y, R);
1353 if (y+1 < h && ((tiles[y*w+x] ^ tiles[(y+1)*w+x]) & LOCKED)) {
1355 if (tiles[y*w+x] & LOCKED)
1356 perturb(w, h, tiles, params->wrapping, rs, x, y+1, U);
1358 perturb(w, h, tiles, params->wrapping, rs, x, y, D);
1363 * Now n counts the number of ambiguous sections we
1364 * have fiddled with. If we haven't managed to decrease
1365 * it from the last time we ran the solver, give up and
1366 * regenerate the entire grid.
1368 if (prevn != -1 && prevn <= n)
1369 goto begin_generation; /* (sorry) */
1375 * The solver will have left a lot of LOCKED bits lying
1376 * around in the tiles array. Remove them.
1378 for (x = 0; x < w*h; x++)
1379 tiles[x] &= ~LOCKED;
1383 * Now compute a list of the possible barrier locations.
1385 barriertree = newtree234(xyd_cmp_nc);
1386 for (y = 0; y < h; y++) {
1387 for (x = 0; x < w; x++) {
1389 if (!(index(params, tiles, x, y) & R) &&
1390 (params->wrapping || x < w-1))
1391 add234(barriertree, new_xyd(x, y, R));
1392 if (!(index(params, tiles, x, y) & D) &&
1393 (params->wrapping || y < h-1))
1394 add234(barriertree, new_xyd(x, y, D));
1399 * Save the unshuffled grid in aux.
1405 solution = snewn(w * h + 1, char);
1406 for (i = 0; i < w * h; i++)
1407 solution[i] = "0123456789abcdef"[tiles[i] & 0xF];
1408 solution[w*h] = '\0';
1414 * Now shuffle the grid.
1416 for (y = 0; y < h; y++) {
1417 for (x = 0; x < w; x++) {
1418 int orig = index(params, tiles, x, y);
1419 int rot = random_upto(rs, 4);
1420 index(params, tiles, x, y) = ROT(orig, rot);
1425 * And now choose barrier locations. (We carefully do this
1426 * _after_ shuffling, so that changing the barrier rate in the
1427 * params while keeping the random seed the same will give the
1428 * same shuffled grid and _only_ change the barrier locations.
1429 * Also the way we choose barrier locations, by repeatedly
1430 * choosing one possibility from the list until we have enough,
1431 * is designed to ensure that raising the barrier rate while
1432 * keeping the seed the same will provide a superset of the
1433 * previous barrier set - i.e. if you ask for 10 barriers, and
1434 * then decide that's still too hard and ask for 20, you'll get
1435 * the original 10 plus 10 more, rather than getting 20 new
1436 * ones and the chance of remembering your first 10.)
1438 nbarriers = (int)(params->barrier_probability * count234(barriertree));
1439 assert(nbarriers >= 0 && nbarriers <= count234(barriertree));
1441 while (nbarriers > 0) {
1444 int x1, y1, d1, x2, y2, d2;
1447 * Extract a randomly chosen barrier from the list.
1449 i = random_upto(rs, count234(barriertree));
1450 xyd = delpos234(barriertree, i);
1452 assert(xyd != NULL);
1456 d1 = xyd->direction;
1459 OFFSET(x2, y2, x1, y1, d1, params);
1462 index(params, barriers, x1, y1) |= d1;
1463 index(params, barriers, x2, y2) |= d2;
1469 * Clean up the rest of the barrier list.
1474 while ( (xyd = delpos234(barriertree, 0)) != NULL)
1477 freetree234(barriertree);
1481 * Finally, encode the grid into a string game description.
1483 * My syntax is extremely simple: each square is encoded as a
1484 * hex digit in which bit 0 means a connection on the right,
1485 * bit 1 means up, bit 2 left and bit 3 down. (i.e. the same
1486 * encoding as used internally). Each digit is followed by
1487 * optional barrier indicators: `v' means a vertical barrier to
1488 * the right of it, and `h' means a horizontal barrier below
1491 desc = snewn(w * h * 3 + 1, char);
1493 for (y = 0; y < h; y++) {
1494 for (x = 0; x < w; x++) {
1495 *p++ = "0123456789abcdef"[index(params, tiles, x, y)];
1496 if ((params->wrapping || x < w-1) &&
1497 (index(params, barriers, x, y) & R))
1499 if ((params->wrapping || y < h-1) &&
1500 (index(params, barriers, x, y) & D))
1504 assert(p - desc <= w*h*3);
1513 static char *validate_desc(game_params *params, char *desc)
1515 int w = params->width, h = params->height;
1518 for (i = 0; i < w*h; i++) {
1519 if (*desc >= '0' && *desc <= '9')
1521 else if (*desc >= 'a' && *desc <= 'f')
1523 else if (*desc >= 'A' && *desc <= 'F')
1526 return "Game description shorter than expected";
1528 return "Game description contained unexpected character";
1530 while (*desc == 'h' || *desc == 'v')
1534 return "Game description longer than expected";
1539 /* ----------------------------------------------------------------------
1540 * Construct an initial game state, given a description and parameters.
1543 static game_state *new_game(midend_data *me, game_params *params, char *desc)
1548 assert(params->width > 0 && params->height > 0);
1549 assert(params->width > 1 || params->height > 1);
1552 * Create a blank game state.
1554 state = snew(game_state);
1555 w = state->width = params->width;
1556 h = state->height = params->height;
1557 state->wrapping = params->wrapping;
1558 state->last_rotate_dir = state->last_rotate_x = state->last_rotate_y = 0;
1559 state->completed = state->used_solve = state->just_used_solve = FALSE;
1560 state->tiles = snewn(state->width * state->height, unsigned char);
1561 memset(state->tiles, 0, state->width * state->height);
1562 state->barriers = snewn(state->width * state->height, unsigned char);
1563 memset(state->barriers, 0, state->width * state->height);
1566 * Parse the game description into the grid.
1568 for (y = 0; y < h; y++) {
1569 for (x = 0; x < w; x++) {
1570 if (*desc >= '0' && *desc <= '9')
1571 tile(state, x, y) = *desc - '0';
1572 else if (*desc >= 'a' && *desc <= 'f')
1573 tile(state, x, y) = *desc - 'a' + 10;
1574 else if (*desc >= 'A' && *desc <= 'F')
1575 tile(state, x, y) = *desc - 'A' + 10;
1578 while (*desc == 'h' || *desc == 'v') {
1585 OFFSET(x2, y2, x, y, d1, state);
1588 barrier(state, x, y) |= d1;
1589 barrier(state, x2, y2) |= d2;
1597 * Set up border barriers if this is a non-wrapping game.
1599 if (!state->wrapping) {
1600 for (x = 0; x < state->width; x++) {
1601 barrier(state, x, 0) |= U;
1602 barrier(state, x, state->height-1) |= D;
1604 for (y = 0; y < state->height; y++) {
1605 barrier(state, 0, y) |= L;
1606 barrier(state, state->width-1, y) |= R;
1610 * We check whether this is de-facto a non-wrapping game
1611 * despite the parameters, in case we were passed the
1612 * description of a non-wrapping game. This is so that we
1613 * can change some aspects of the UI behaviour.
1615 state->wrapping = FALSE;
1616 for (x = 0; x < state->width; x++)
1617 if (!(barrier(state, x, 0) & U) ||
1618 !(barrier(state, x, state->height-1) & D))
1619 state->wrapping = TRUE;
1620 for (y = 0; y < state->width; y++)
1621 if (!(barrier(state, 0, y) & L) ||
1622 !(barrier(state, state->width-1, y) & R))
1623 state->wrapping = TRUE;
1629 static game_state *dup_game(game_state *state)
1633 ret = snew(game_state);
1634 ret->width = state->width;
1635 ret->height = state->height;
1636 ret->wrapping = state->wrapping;
1637 ret->completed = state->completed;
1638 ret->used_solve = state->used_solve;
1639 ret->just_used_solve = state->just_used_solve;
1640 ret->last_rotate_dir = state->last_rotate_dir;
1641 ret->last_rotate_x = state->last_rotate_x;
1642 ret->last_rotate_y = state->last_rotate_y;
1643 ret->tiles = snewn(state->width * state->height, unsigned char);
1644 memcpy(ret->tiles, state->tiles, state->width * state->height);
1645 ret->barriers = snewn(state->width * state->height, unsigned char);
1646 memcpy(ret->barriers, state->barriers, state->width * state->height);
1651 static void free_game(game_state *state)
1653 sfree(state->tiles);
1654 sfree(state->barriers);
1658 static char *solve_game(game_state *state, game_state *currstate,
1659 char *aux, char **error)
1661 unsigned char *tiles;
1663 int retlen, retsize;
1666 tiles = snewn(state->width * state->height, unsigned char);
1670 * Run the internal solver on the provided grid. This might
1671 * not yield a complete solution.
1673 memcpy(tiles, state->tiles, state->width * state->height);
1674 net_solver(state->width, state->height, tiles,
1675 state->barriers, state->wrapping);
1677 for (i = 0; i < state->width * state->height; i++) {
1680 if (c >= '0' && c <= '9')
1682 else if (c >= 'a' && c <= 'f')
1683 tiles[i] = c - 'a' + 10;
1684 else if (c >= 'A' && c <= 'F')
1685 tiles[i] = c - 'A' + 10;
1690 * Now construct a string which can be passed to execute_move()
1691 * to transform the current grid into the solved one.
1694 ret = snewn(retsize, char);
1696 ret[retlen++] = 'S';
1698 for (i = 0; i < state->width * state->height; i++) {
1699 int from = currstate->tiles[i], to = tiles[i];
1700 int ft = from & (R|L|U|D), tt = to & (R|L|U|D);
1701 int x = i % state->width, y = i / state->width;
1703 char buf[80], *p = buf;
1706 continue; /* nothing needs doing at all */
1709 * To transform this tile into the desired tile: first
1710 * unlock the tile if it's locked, then rotate it if
1711 * necessary, then lock it if necessary.
1714 p += sprintf(p, ";L%d,%d", x, y);
1718 else if (tt == C(ft))
1720 else if (tt == F(ft))
1727 p += sprintf(p, ";%c%d,%d", chr, x, y);
1730 p += sprintf(p, ";L%d,%d", x, y);
1733 if (retlen + (p - buf) >= retsize) {
1734 retsize = retlen + (p - buf) + 512;
1735 ret = sresize(ret, retsize, char);
1737 memcpy(ret+retlen, buf, p - buf);
1742 assert(retlen < retsize);
1744 ret = sresize(ret, retlen+1, char);
1751 static char *game_text_format(game_state *state)
1756 /* ----------------------------------------------------------------------
1761 * Compute which squares are reachable from the centre square, as a
1762 * quick visual aid to determining how close the game is to
1763 * completion. This is also a simple way to tell if the game _is_
1764 * completed - just call this function and see whether every square
1767 static unsigned char *compute_active(game_state *state, int cx, int cy)
1769 unsigned char *active;
1773 active = snewn(state->width * state->height, unsigned char);
1774 memset(active, 0, state->width * state->height);
1777 * We only store (x,y) pairs in todo, but it's easier to reuse
1778 * xyd_cmp and just store direction 0 every time.
1780 todo = newtree234(xyd_cmp_nc);
1781 index(state, active, cx, cy) = ACTIVE;
1782 add234(todo, new_xyd(cx, cy, 0));
1784 while ( (xyd = delpos234(todo, 0)) != NULL) {
1785 int x1, y1, d1, x2, y2, d2;
1791 for (d1 = 1; d1 < 0x10; d1 <<= 1) {
1792 OFFSET(x2, y2, x1, y1, d1, state);
1796 * If the next tile in this direction is connected to
1797 * us, and there isn't a barrier in the way, and it
1798 * isn't already marked active, then mark it active and
1799 * add it to the to-examine list.
1801 if ((tile(state, x1, y1) & d1) &&
1802 (tile(state, x2, y2) & d2) &&
1803 !(barrier(state, x1, y1) & d1) &&
1804 !index(state, active, x2, y2)) {
1805 index(state, active, x2, y2) = ACTIVE;
1806 add234(todo, new_xyd(x2, y2, 0));
1810 /* Now we expect the todo list to have shrunk to zero size. */
1811 assert(count234(todo) == 0);
1818 int org_x, org_y; /* origin */
1819 int cx, cy; /* source tile (game coordinates) */
1822 random_state *rs; /* used for jumbling */
1825 static game_ui *new_ui(game_state *state)
1829 game_ui *ui = snew(game_ui);
1830 ui->org_x = ui->org_y = 0;
1831 ui->cur_x = ui->cx = state->width / 2;
1832 ui->cur_y = ui->cy = state->height / 2;
1833 ui->cur_visible = FALSE;
1834 get_random_seed(&seed, &seedsize);
1835 ui->rs = random_init(seed, seedsize);
1841 static void free_ui(game_ui *ui)
1843 random_free(ui->rs);
1847 static char *encode_ui(game_ui *ui)
1851 * We preserve the origin and centre-point coordinates over a
1854 sprintf(buf, "O%d,%d;C%d,%d", ui->org_x, ui->org_y, ui->cx, ui->cy);
1858 static void decode_ui(game_ui *ui, char *encoding)
1860 sscanf(encoding, "O%d,%d;C%d,%d",
1861 &ui->org_x, &ui->org_y, &ui->cx, &ui->cy);
1864 static void game_changed_state(game_ui *ui, game_state *oldstate,
1865 game_state *newstate)
1869 struct game_drawstate {
1874 unsigned char *visible;
1877 /* ----------------------------------------------------------------------
1880 static char *interpret_move(game_state *state, game_ui *ui,
1881 game_drawstate *ds, int x, int y, int button)
1884 int tx = -1, ty = -1, dir = 0;
1885 int shift = button & MOD_SHFT, ctrl = button & MOD_CTRL;
1887 NONE, ROTATE_LEFT, ROTATE_180, ROTATE_RIGHT, TOGGLE_LOCK, JUMBLE,
1888 MOVE_ORIGIN, MOVE_SOURCE, MOVE_ORIGIN_AND_SOURCE, MOVE_CURSOR
1891 button &= ~MOD_MASK;
1895 if (button == LEFT_BUTTON ||
1896 button == MIDDLE_BUTTON ||
1897 button == RIGHT_BUTTON) {
1899 if (ui->cur_visible) {
1900 ui->cur_visible = FALSE;
1905 * The button must have been clicked on a valid tile.
1907 x -= WINDOW_OFFSET + TILE_BORDER;
1908 y -= WINDOW_OFFSET + TILE_BORDER;
1913 if (tx >= state->width || ty >= state->height)
1915 /* Transform from physical to game coords */
1916 tx = (tx + ui->org_x) % state->width;
1917 ty = (ty + ui->org_y) % state->height;
1918 if (x % TILE_SIZE >= TILE_SIZE - TILE_BORDER ||
1919 y % TILE_SIZE >= TILE_SIZE - TILE_BORDER)
1922 action = button == LEFT_BUTTON ? ROTATE_LEFT :
1923 button == RIGHT_BUTTON ? ROTATE_RIGHT : TOGGLE_LOCK;
1924 } else if (button == CURSOR_UP || button == CURSOR_DOWN ||
1925 button == CURSOR_RIGHT || button == CURSOR_LEFT) {
1927 case CURSOR_UP: dir = U; break;
1928 case CURSOR_DOWN: dir = D; break;
1929 case CURSOR_LEFT: dir = L; break;
1930 case CURSOR_RIGHT: dir = R; break;
1931 default: return nullret;
1933 if (shift && ctrl) action = MOVE_ORIGIN_AND_SOURCE;
1934 else if (shift) action = MOVE_ORIGIN;
1935 else if (ctrl) action = MOVE_SOURCE;
1936 else action = MOVE_CURSOR;
1937 } else if (button == 'a' || button == 's' || button == 'd' ||
1938 button == 'A' || button == 'S' || button == 'D' ||
1939 button == 'f' || button == 'F' ||
1940 button == CURSOR_SELECT) {
1943 if (button == 'a' || button == 'A' || button == CURSOR_SELECT)
1944 action = ROTATE_LEFT;
1945 else if (button == 's' || button == 'S')
1946 action = TOGGLE_LOCK;
1947 else if (button == 'd' || button == 'D')
1948 action = ROTATE_RIGHT;
1949 else if (button == 'f' || button == 'F')
1950 action = ROTATE_180;
1951 ui->cur_visible = TRUE;
1952 } else if (button == 'j' || button == 'J') {
1953 /* XXX should we have some mouse control for this? */
1959 * The middle button locks or unlocks a tile. (A locked tile
1960 * cannot be turned, and is visually marked as being locked.
1961 * This is a convenience for the player, so that once they are
1962 * sure which way round a tile goes, they can lock it and thus
1963 * avoid forgetting later on that they'd already done that one;
1964 * and the locking also prevents them turning the tile by
1965 * accident. If they change their mind, another middle click
1968 if (action == TOGGLE_LOCK) {
1970 sprintf(buf, "L%d,%d", tx, ty);
1972 } else if (action == ROTATE_LEFT || action == ROTATE_RIGHT ||
1973 action == ROTATE_180) {
1977 * The left and right buttons have no effect if clicked on a
1980 if (tile(state, tx, ty) & LOCKED)
1984 * Otherwise, turn the tile one way or the other. Left button
1985 * turns anticlockwise; right button turns clockwise.
1987 sprintf(buf, "%c%d,%d", (int)(action == ROTATE_LEFT ? 'A' :
1988 action == ROTATE_RIGHT ? 'C' : 'F'), tx, ty);
1990 } else if (action == JUMBLE) {
1992 * Jumble all unlocked tiles to random orientations.
1999 * Maximum string length assumes no int can be converted to
2000 * decimal and take more than 11 digits!
2002 maxlen = state->width * state->height * 25 + 3;
2004 ret = snewn(maxlen, char);
2008 for (jy = 0; jy < state->height; jy++) {
2009 for (jx = 0; jx < state->width; jx++) {
2010 if (!(tile(state, jx, jy) & LOCKED)) {
2011 int rot = random_upto(ui->rs, 4);
2013 p += sprintf(p, ";%c%d,%d", "AFC"[rot-1], jx, jy);
2019 assert(p - ret < maxlen);
2020 ret = sresize(ret, p - ret, char);
2023 } else if (action == MOVE_ORIGIN || action == MOVE_SOURCE ||
2024 action == MOVE_ORIGIN_AND_SOURCE || action == MOVE_CURSOR) {
2026 if (action == MOVE_ORIGIN || action == MOVE_ORIGIN_AND_SOURCE) {
2027 if (state->wrapping) {
2028 OFFSET(ui->org_x, ui->org_y, ui->org_x, ui->org_y, dir, state);
2029 } else return nullret; /* disallowed for non-wrapping grids */
2031 if (action == MOVE_SOURCE || action == MOVE_ORIGIN_AND_SOURCE) {
2032 OFFSET(ui->cx, ui->cy, ui->cx, ui->cy, dir, state);
2034 if (action == MOVE_CURSOR) {
2035 OFFSET(ui->cur_x, ui->cur_y, ui->cur_x, ui->cur_y, dir, state);
2036 ui->cur_visible = TRUE;
2044 static game_state *execute_move(game_state *from, char *move)
2047 int tx, ty, n, noanim, orig;
2049 ret = dup_game(from);
2050 ret->just_used_solve = FALSE;
2052 if (move[0] == 'J' || move[0] == 'S') {
2054 ret->just_used_solve = ret->used_solve = TRUE;
2063 ret->last_rotate_dir = 0; /* suppress animation */
2064 ret->last_rotate_x = ret->last_rotate_y = 0;
2067 if ((move[0] == 'A' || move[0] == 'C' ||
2068 move[0] == 'F' || move[0] == 'L') &&
2069 sscanf(move+1, "%d,%d%n", &tx, &ty, &n) >= 2 &&
2070 tx >= 0 && tx < from->width && ty >= 0 && ty < from->height) {
2071 orig = tile(ret, tx, ty);
2072 if (move[0] == 'A') {
2073 tile(ret, tx, ty) = A(orig);
2075 ret->last_rotate_dir = +1;
2076 } else if (move[0] == 'F') {
2077 tile(ret, tx, ty) = F(orig);
2079 ret->last_rotate_dir = +2; /* + for sake of argument */
2080 } else if (move[0] == 'C') {
2081 tile(ret, tx, ty) = C(orig);
2083 ret->last_rotate_dir = -1;
2085 assert(move[0] == 'L');
2086 tile(ret, tx, ty) ^= LOCKED;
2090 if (*move == ';') move++;
2097 ret->last_rotate_x = tx;
2098 ret->last_rotate_y = ty;
2102 * Check whether the game has been completed.
2104 * For this purpose it doesn't matter where the source square
2105 * is, because we can start from anywhere and correctly
2106 * determine whether the game is completed.
2109 unsigned char *active = compute_active(ret, 0, 0);
2111 int complete = TRUE;
2113 for (x1 = 0; x1 < ret->width; x1++)
2114 for (y1 = 0; y1 < ret->height; y1++)
2115 if ((tile(ret, x1, y1) & 0xF) && !index(ret, active, x1, y1)) {
2117 goto break_label; /* break out of two loops at once */
2124 ret->completed = TRUE;
2131 /* ----------------------------------------------------------------------
2132 * Routines for drawing the game position on the screen.
2135 static game_drawstate *game_new_drawstate(game_state *state)
2137 game_drawstate *ds = snew(game_drawstate);
2139 ds->started = FALSE;
2140 ds->width = state->width;
2141 ds->height = state->height;
2142 ds->org_x = ds->org_y = -1;
2143 ds->visible = snewn(state->width * state->height, unsigned char);
2144 ds->tilesize = 0; /* undecided yet */
2145 memset(ds->visible, 0xFF, state->width * state->height);
2150 static void game_free_drawstate(game_drawstate *ds)
2156 static void game_compute_size(game_params *params, int tilesize,
2159 *x = WINDOW_OFFSET * 2 + tilesize * params->width + TILE_BORDER;
2160 *y = WINDOW_OFFSET * 2 + tilesize * params->height + TILE_BORDER;
2163 static void game_set_size(game_drawstate *ds, game_params *params,
2166 ds->tilesize = tilesize;
2169 static float *game_colours(frontend *fe, game_state *state, int *ncolours)
2173 ret = snewn(NCOLOURS * 3, float);
2174 *ncolours = NCOLOURS;
2177 * Basic background colour is whatever the front end thinks is
2178 * a sensible default.
2180 frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
2185 ret[COL_WIRE * 3 + 0] = 0.0F;
2186 ret[COL_WIRE * 3 + 1] = 0.0F;
2187 ret[COL_WIRE * 3 + 2] = 0.0F;
2190 * Powered wires and powered endpoints are cyan.
2192 ret[COL_POWERED * 3 + 0] = 0.0F;
2193 ret[COL_POWERED * 3 + 1] = 1.0F;
2194 ret[COL_POWERED * 3 + 2] = 1.0F;
2199 ret[COL_BARRIER * 3 + 0] = 1.0F;
2200 ret[COL_BARRIER * 3 + 1] = 0.0F;
2201 ret[COL_BARRIER * 3 + 2] = 0.0F;
2204 * Unpowered endpoints are blue.
2206 ret[COL_ENDPOINT * 3 + 0] = 0.0F;
2207 ret[COL_ENDPOINT * 3 + 1] = 0.0F;
2208 ret[COL_ENDPOINT * 3 + 2] = 1.0F;
2211 * Tile borders are a darker grey than the background.
2213 ret[COL_BORDER * 3 + 0] = 0.5F * ret[COL_BACKGROUND * 3 + 0];
2214 ret[COL_BORDER * 3 + 1] = 0.5F * ret[COL_BACKGROUND * 3 + 1];
2215 ret[COL_BORDER * 3 + 2] = 0.5F * ret[COL_BACKGROUND * 3 + 2];
2218 * Locked tiles are a grey in between those two.
2220 ret[COL_LOCKED * 3 + 0] = 0.75F * ret[COL_BACKGROUND * 3 + 0];
2221 ret[COL_LOCKED * 3 + 1] = 0.75F * ret[COL_BACKGROUND * 3 + 1];
2222 ret[COL_LOCKED * 3 + 2] = 0.75F * ret[COL_BACKGROUND * 3 + 2];
2227 static void draw_thick_line(frontend *fe, int x1, int y1, int x2, int y2,
2230 draw_line(fe, x1-1, y1, x2-1, y2, COL_WIRE);
2231 draw_line(fe, x1+1, y1, x2+1, y2, COL_WIRE);
2232 draw_line(fe, x1, y1-1, x2, y2-1, COL_WIRE);
2233 draw_line(fe, x1, y1+1, x2, y2+1, COL_WIRE);
2234 draw_line(fe, x1, y1, x2, y2, colour);
2237 static void draw_rect_coords(frontend *fe, int x1, int y1, int x2, int y2,
2240 int mx = (x1 < x2 ? x1 : x2);
2241 int my = (y1 < y2 ? y1 : y2);
2242 int dx = (x2 + x1 - 2*mx + 1);
2243 int dy = (y2 + y1 - 2*my + 1);
2245 draw_rect(fe, mx, my, dx, dy, colour);
2249 * draw_barrier_corner() and draw_barrier() are passed physical coords
2251 static void draw_barrier_corner(frontend *fe, game_drawstate *ds,
2252 int x, int y, int dx, int dy, int phase)
2254 int bx = WINDOW_OFFSET + TILE_SIZE * x;
2255 int by = WINDOW_OFFSET + TILE_SIZE * y;
2258 x1 = (dx > 0 ? TILE_SIZE+TILE_BORDER-1 : 0);
2259 y1 = (dy > 0 ? TILE_SIZE+TILE_BORDER-1 : 0);
2262 draw_rect_coords(fe, bx+x1+dx, by+y1,
2263 bx+x1-TILE_BORDER*dx, by+y1-(TILE_BORDER-1)*dy,
2265 draw_rect_coords(fe, bx+x1, by+y1+dy,
2266 bx+x1-(TILE_BORDER-1)*dx, by+y1-TILE_BORDER*dy,
2269 draw_rect_coords(fe, bx+x1, by+y1,
2270 bx+x1-(TILE_BORDER-1)*dx, by+y1-(TILE_BORDER-1)*dy,
2275 static void draw_barrier(frontend *fe, game_drawstate *ds,
2276 int x, int y, int dir, int phase)
2278 int bx = WINDOW_OFFSET + TILE_SIZE * x;
2279 int by = WINDOW_OFFSET + TILE_SIZE * y;
2282 x1 = (X(dir) > 0 ? TILE_SIZE : X(dir) == 0 ? TILE_BORDER : 0);
2283 y1 = (Y(dir) > 0 ? TILE_SIZE : Y(dir) == 0 ? TILE_BORDER : 0);
2284 w = (X(dir) ? TILE_BORDER : TILE_SIZE - TILE_BORDER);
2285 h = (Y(dir) ? TILE_BORDER : TILE_SIZE - TILE_BORDER);
2288 draw_rect(fe, bx+x1-X(dir), by+y1-Y(dir), w, h, COL_WIRE);
2290 draw_rect(fe, bx+x1, by+y1, w, h, COL_BARRIER);
2295 * draw_tile() is passed physical coordinates
2297 static void draw_tile(frontend *fe, game_state *state, game_drawstate *ds,
2298 int x, int y, int tile, int src, float angle, int cursor)
2300 int bx = WINDOW_OFFSET + TILE_SIZE * x;
2301 int by = WINDOW_OFFSET + TILE_SIZE * y;
2303 float cx, cy, ex, ey, tx, ty;
2304 int dir, col, phase;
2307 * When we draw a single tile, we must draw everything up to
2308 * and including the borders around the tile. This means that
2309 * if the neighbouring tiles have connections to those borders,
2310 * we must draw those connections on the borders themselves.
2313 clip(fe, bx, by, TILE_SIZE+TILE_BORDER, TILE_SIZE+TILE_BORDER);
2316 * So. First blank the tile out completely: draw a big
2317 * rectangle in border colour, and a smaller rectangle in
2318 * background colour to fill it in.
2320 draw_rect(fe, bx, by, TILE_SIZE+TILE_BORDER, TILE_SIZE+TILE_BORDER,
2322 draw_rect(fe, bx+TILE_BORDER, by+TILE_BORDER,
2323 TILE_SIZE-TILE_BORDER, TILE_SIZE-TILE_BORDER,
2324 tile & LOCKED ? COL_LOCKED : COL_BACKGROUND);
2327 * Draw an inset outline rectangle as a cursor, in whichever of
2328 * COL_LOCKED and COL_BACKGROUND we aren't currently drawing
2332 draw_line(fe, bx+TILE_SIZE/8, by+TILE_SIZE/8,
2333 bx+TILE_SIZE/8, by+TILE_SIZE-TILE_SIZE/8,
2334 tile & LOCKED ? COL_BACKGROUND : COL_LOCKED);
2335 draw_line(fe, bx+TILE_SIZE/8, by+TILE_SIZE/8,
2336 bx+TILE_SIZE-TILE_SIZE/8, by+TILE_SIZE/8,
2337 tile & LOCKED ? COL_BACKGROUND : COL_LOCKED);
2338 draw_line(fe, bx+TILE_SIZE-TILE_SIZE/8, by+TILE_SIZE/8,
2339 bx+TILE_SIZE-TILE_SIZE/8, by+TILE_SIZE-TILE_SIZE/8,
2340 tile & LOCKED ? COL_BACKGROUND : COL_LOCKED);
2341 draw_line(fe, bx+TILE_SIZE/8, by+TILE_SIZE-TILE_SIZE/8,
2342 bx+TILE_SIZE-TILE_SIZE/8, by+TILE_SIZE-TILE_SIZE/8,
2343 tile & LOCKED ? COL_BACKGROUND : COL_LOCKED);
2347 * Set up the rotation matrix.
2349 matrix[0] = (float)cos(angle * PI / 180.0);
2350 matrix[1] = (float)-sin(angle * PI / 180.0);
2351 matrix[2] = (float)sin(angle * PI / 180.0);
2352 matrix[3] = (float)cos(angle * PI / 180.0);
2357 cx = cy = TILE_BORDER + (TILE_SIZE-TILE_BORDER) / 2.0F - 0.5F;
2358 col = (tile & ACTIVE ? COL_POWERED : COL_WIRE);
2359 for (dir = 1; dir < 0x10; dir <<= 1) {
2361 ex = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * X(dir);
2362 ey = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * Y(dir);
2363 MATMUL(tx, ty, matrix, ex, ey);
2364 draw_thick_line(fe, bx+(int)cx, by+(int)cy,
2365 bx+(int)(cx+tx), by+(int)(cy+ty),
2369 for (dir = 1; dir < 0x10; dir <<= 1) {
2371 ex = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * X(dir);
2372 ey = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * Y(dir);
2373 MATMUL(tx, ty, matrix, ex, ey);
2374 draw_line(fe, bx+(int)cx, by+(int)cy,
2375 bx+(int)(cx+tx), by+(int)(cy+ty), col);
2380 * Draw the box in the middle. We do this in blue if the tile
2381 * is an unpowered endpoint, in cyan if the tile is a powered
2382 * endpoint, in black if the tile is the centrepiece, and
2383 * otherwise not at all.
2388 else if (COUNT(tile) == 1) {
2389 col = (tile & ACTIVE ? COL_POWERED : COL_ENDPOINT);
2394 points[0] = +1; points[1] = +1;
2395 points[2] = +1; points[3] = -1;
2396 points[4] = -1; points[5] = -1;
2397 points[6] = -1; points[7] = +1;
2399 for (i = 0; i < 8; i += 2) {
2400 ex = (TILE_SIZE * 0.24F) * points[i];
2401 ey = (TILE_SIZE * 0.24F) * points[i+1];
2402 MATMUL(tx, ty, matrix, ex, ey);
2403 points[i] = bx+(int)(cx+tx);
2404 points[i+1] = by+(int)(cy+ty);
2407 draw_polygon(fe, points, 4, col, COL_WIRE);
2411 * Draw the points on the border if other tiles are connected
2414 for (dir = 1; dir < 0x10; dir <<= 1) {
2415 int dx, dy, px, py, lx, ly, vx, vy, ox, oy;
2423 if (ox < 0 || ox >= state->width || oy < 0 || oy >= state->height)
2426 if (!(tile(state, GX(ox), GY(oy)) & F(dir)))
2429 px = bx + (int)(dx>0 ? TILE_SIZE + TILE_BORDER - 1 : dx<0 ? 0 : cx);
2430 py = by + (int)(dy>0 ? TILE_SIZE + TILE_BORDER - 1 : dy<0 ? 0 : cy);
2431 lx = dx * (TILE_BORDER-1);
2432 ly = dy * (TILE_BORDER-1);
2436 if (angle == 0.0 && (tile & dir)) {
2438 * If we are fully connected to the other tile, we must
2439 * draw right across the tile border. (We can use our
2440 * own ACTIVE state to determine what colour to do this
2441 * in: if we are fully connected to the other tile then
2442 * the two ACTIVE states will be the same.)
2444 draw_rect_coords(fe, px-vx, py-vy, px+lx+vx, py+ly+vy, COL_WIRE);
2445 draw_rect_coords(fe, px, py, px+lx, py+ly,
2446 (tile & ACTIVE) ? COL_POWERED : COL_WIRE);
2449 * The other tile extends into our border, but isn't
2450 * actually connected to us. Just draw a single black
2453 draw_rect_coords(fe, px, py, px, py, COL_WIRE);
2458 * Draw barrier corners, and then barriers.
2460 for (phase = 0; phase < 2; phase++) {
2461 for (dir = 1; dir < 0x10; dir <<= 1) {
2462 int x1, y1, corner = FALSE;
2464 * If at least one barrier terminates at the corner
2465 * between dir and A(dir), draw a barrier corner.
2467 if (barrier(state, GX(x), GY(y)) & (dir | A(dir))) {
2471 * Only count barriers terminating at this corner
2472 * if they're physically next to the corner. (That
2473 * is, if they've wrapped round from the far side
2474 * of the screen, they don't count.)
2478 if (x1 >= 0 && x1 < state->width &&
2479 y1 >= 0 && y1 < state->height &&
2480 (barrier(state, GX(x1), GY(y1)) & A(dir))) {
2485 if (x1 >= 0 && x1 < state->width &&
2486 y1 >= 0 && y1 < state->height &&
2487 (barrier(state, GX(x1), GY(y1)) & dir))
2494 * At least one barrier terminates here. Draw a
2497 draw_barrier_corner(fe, ds, x, y,
2498 X(dir)+X(A(dir)), Y(dir)+Y(A(dir)),
2503 for (dir = 1; dir < 0x10; dir <<= 1)
2504 if (barrier(state, GX(x), GY(y)) & dir)
2505 draw_barrier(fe, ds, x, y, dir, phase);
2510 draw_update(fe, bx, by, TILE_SIZE+TILE_BORDER, TILE_SIZE+TILE_BORDER);
2513 static void game_redraw(frontend *fe, game_drawstate *ds, game_state *oldstate,
2514 game_state *state, int dir, game_ui *ui, float t, float ft)
2516 int x, y, tx, ty, frame, last_rotate_dir, moved_origin = FALSE;
2517 unsigned char *active;
2521 * Clear the screen, and draw the exterior barrier lines, if
2522 * this is our first call or if the origin has changed.
2524 if (!ds->started || ui->org_x != ds->org_x || ui->org_y != ds->org_y) {
2530 WINDOW_OFFSET * 2 + TILE_SIZE * state->width + TILE_BORDER,
2531 WINDOW_OFFSET * 2 + TILE_SIZE * state->height + TILE_BORDER,
2534 ds->org_x = ui->org_x;
2535 ds->org_y = ui->org_y;
2536 moved_origin = TRUE;
2538 draw_update(fe, 0, 0,
2539 WINDOW_OFFSET*2 + TILE_SIZE*state->width + TILE_BORDER,
2540 WINDOW_OFFSET*2 + TILE_SIZE*state->height + TILE_BORDER);
2542 for (phase = 0; phase < 2; phase++) {
2544 for (x = 0; x < ds->width; x++) {
2545 if (x+1 < ds->width) {
2546 if (barrier(state, GX(x), GY(0)) & R)
2547 draw_barrier_corner(fe, ds, x, -1, +1, +1, phase);
2548 if (barrier(state, GX(x), GY(ds->height-1)) & R)
2549 draw_barrier_corner(fe, ds, x, ds->height, +1, -1, phase);
2551 if (barrier(state, GX(x), GY(0)) & U) {
2552 draw_barrier_corner(fe, ds, x, -1, -1, +1, phase);
2553 draw_barrier_corner(fe, ds, x, -1, +1, +1, phase);
2554 draw_barrier(fe, ds, x, -1, D, phase);
2556 if (barrier(state, GX(x), GY(ds->height-1)) & D) {
2557 draw_barrier_corner(fe, ds, x, ds->height, -1, -1, phase);
2558 draw_barrier_corner(fe, ds, x, ds->height, +1, -1, phase);
2559 draw_barrier(fe, ds, x, ds->height, U, phase);
2563 for (y = 0; y < ds->height; y++) {
2564 if (y+1 < ds->height) {
2565 if (barrier(state, GX(0), GY(y)) & D)
2566 draw_barrier_corner(fe, ds, -1, y, +1, +1, phase);
2567 if (barrier(state, GX(ds->width-1), GY(y)) & D)
2568 draw_barrier_corner(fe, ds, ds->width, y, -1, +1, phase);
2570 if (barrier(state, GX(0), GY(y)) & L) {
2571 draw_barrier_corner(fe, ds, -1, y, +1, -1, phase);
2572 draw_barrier_corner(fe, ds, -1, y, +1, +1, phase);
2573 draw_barrier(fe, ds, -1, y, R, phase);
2575 if (barrier(state, GX(ds->width-1), GY(y)) & R) {
2576 draw_barrier_corner(fe, ds, ds->width, y, -1, -1, phase);
2577 draw_barrier_corner(fe, ds, ds->width, y, -1, +1, phase);
2578 draw_barrier(fe, ds, ds->width, y, L, phase);
2585 last_rotate_dir = dir==-1 ? oldstate->last_rotate_dir :
2586 state->last_rotate_dir;
2587 if (oldstate && (t < ROTATE_TIME) && last_rotate_dir) {
2589 * We're animating a single tile rotation. Find the turning
2592 tx = (dir==-1 ? oldstate->last_rotate_x : state->last_rotate_x);
2593 ty = (dir==-1 ? oldstate->last_rotate_y : state->last_rotate_y);
2594 angle = last_rotate_dir * dir * 90.0F * (t / ROTATE_TIME);
2601 * We're animating a completion flash. Find which frame
2604 frame = (int)(ft / FLASH_FRAME);
2608 * Draw any tile which differs from the way it was last drawn.
2610 active = compute_active(state, ui->cx, ui->cy);
2612 for (x = 0; x < ds->width; x++)
2613 for (y = 0; y < ds->height; y++) {
2614 unsigned char c = tile(state, GX(x), GY(y)) |
2615 index(state, active, GX(x), GY(y));
2616 int is_src = GX(x) == ui->cx && GY(y) == ui->cy;
2617 int is_anim = GX(x) == tx && GY(y) == ty;
2618 int is_cursor = ui->cur_visible &&
2619 GX(x) == ui->cur_x && GY(y) == ui->cur_y;
2622 * In a completion flash, we adjust the LOCKED bit
2623 * depending on our distance from the centre point and
2627 int rcx = RX(ui->cx), rcy = RY(ui->cy);
2628 int xdist, ydist, dist;
2629 xdist = (x < rcx ? rcx - x : x - rcx);
2630 ydist = (y < rcy ? rcy - y : y - rcy);
2631 dist = (xdist > ydist ? xdist : ydist);
2633 if (frame >= dist && frame < dist+4) {
2634 int lock = (frame - dist) & 1;
2635 lock = lock ? LOCKED : 0;
2636 c = (c &~ LOCKED) | lock;
2641 index(state, ds->visible, x, y) != c ||
2642 index(state, ds->visible, x, y) == 0xFF ||
2643 is_src || is_anim || is_cursor) {
2644 draw_tile(fe, state, ds, x, y, c,
2645 is_src, (is_anim ? angle : 0.0F), is_cursor);
2646 if (is_src || is_anim || is_cursor)
2647 index(state, ds->visible, x, y) = 0xFF;
2649 index(state, ds->visible, x, y) = c;
2654 * Update the status bar.
2657 char statusbuf[256];
2660 n = state->width * state->height;
2661 for (i = a = n2 = 0; i < n; i++) {
2664 if (state->tiles[i] & 0xF)
2668 sprintf(statusbuf, "%sActive: %d/%d",
2669 (state->used_solve ? "Auto-solved. " :
2670 state->completed ? "COMPLETED! " : ""), a, n2);
2672 status_bar(fe, statusbuf);
2678 static float game_anim_length(game_state *oldstate,
2679 game_state *newstate, int dir, game_ui *ui)
2681 int last_rotate_dir;
2684 * Don't animate an auto-solve move.
2686 if ((dir > 0 && newstate->just_used_solve) ||
2687 (dir < 0 && oldstate->just_used_solve))
2691 * Don't animate if last_rotate_dir is zero.
2693 last_rotate_dir = dir==-1 ? oldstate->last_rotate_dir :
2694 newstate->last_rotate_dir;
2695 if (last_rotate_dir)
2701 static float game_flash_length(game_state *oldstate,
2702 game_state *newstate, int dir, game_ui *ui)
2705 * If the game has just been completed, we display a completion
2708 if (!oldstate->completed && newstate->completed &&
2709 !oldstate->used_solve && !newstate->used_solve) {
2711 if (size < newstate->width)
2712 size = newstate->width;
2713 if (size < newstate->height)
2714 size = newstate->height;
2715 return FLASH_FRAME * (size+4);
2721 static int game_wants_statusbar(void)
2726 static int game_timing_state(game_state *state, game_ui *ui)
2735 const struct game thegame = {
2743 TRUE, game_configure, custom_params,
2751 FALSE, game_text_format,
2759 PREFERRED_TILE_SIZE, game_compute_size, game_set_size,
2762 game_free_drawstate,
2766 game_wants_statusbar,
2767 FALSE, game_timing_state,
2768 0, /* mouse_priorities */