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;
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.
386 unsigned char *marked;
392 static struct todo *todo_new(int maxsize)
394 struct todo *todo = snew(struct todo);
395 todo->marked = snewn(maxsize, unsigned char);
396 memset(todo->marked, 0, maxsize);
397 todo->buflen = maxsize + 1;
398 todo->buffer = snewn(todo->buflen, int);
399 todo->head = todo->tail = 0;
403 static void todo_free(struct todo *todo)
410 static void todo_add(struct todo *todo, int index)
412 if (todo->marked[index])
413 return; /* already on the list */
414 todo->marked[index] = TRUE;
415 todo->buffer[todo->tail++] = index;
416 if (todo->tail == todo->buflen)
420 static int todo_get(struct todo *todo) {
423 if (todo->head == todo->tail)
424 return -1; /* list is empty */
425 ret = todo->buffer[todo->head++];
426 if (todo->head == todo->buflen)
428 todo->marked[ret] = FALSE;
433 static int net_solver(int w, int h, unsigned char *tiles,
434 unsigned char *barriers, int wrapping)
436 unsigned char *tilestate;
437 unsigned char *edgestate;
446 * Set up the solver's data structures.
450 * tilestate stores the possible orientations of each tile.
451 * There are up to four of these, so we'll index the array in
452 * fours. tilestate[(y * w + x) * 4] and its three successive
453 * members give the possible orientations, clearing to 255 from
454 * the end as things are ruled out.
456 * In this loop we also count up the area of the grid (which is
457 * not _necessarily_ equal to w*h, because there might be one
458 * or more blank squares present. This will never happen in a
459 * grid generated _by_ this program, but it's worth keeping the
460 * solver as general as possible.)
462 tilestate = snewn(w * h * 4, unsigned char);
464 for (i = 0; i < w*h; i++) {
465 tilestate[i * 4] = tiles[i] & 0xF;
466 for (j = 1; j < 4; j++) {
467 if (tilestate[i * 4 + j - 1] == 255 ||
468 A(tilestate[i * 4 + j - 1]) == tilestate[i * 4])
469 tilestate[i * 4 + j] = 255;
471 tilestate[i * 4 + j] = A(tilestate[i * 4 + j - 1]);
478 * edgestate stores the known state of each edge. It is 0 for
479 * unknown, 1 for open (connected) and 2 for closed (not
482 * In principle we need only worry about each edge once each,
483 * but in fact it's easier to track each edge twice so that we
484 * can reference it from either side conveniently. Also I'm
485 * going to allocate _five_ bytes per tile, rather than the
486 * obvious four, so that I can index edgestate[(y*w+x) * 5 + d]
487 * where d is 1,2,4,8 and they never overlap.
489 edgestate = snewn((w * h - 1) * 5 + 9, unsigned char);
490 memset(edgestate, 0, (w * h - 1) * 5 + 9);
493 * deadends tracks which edges have dead ends on them. It is
494 * indexed by tile and direction: deadends[(y*w+x) * 5 + d]
495 * tells you whether heading out of tile (x,y) in direction d
496 * can reach a limited amount of the grid. Values are area+1
497 * (no dead end known) or less than that (can reach _at most_
498 * this many other tiles by heading this way out of this tile).
500 deadends = snewn((w * h - 1) * 5 + 9, int);
501 for (i = 0; i < (w * h - 1) * 5 + 9; i++)
502 deadends[i] = area+1;
505 * equivalence tracks which sets of tiles are known to be
506 * connected to one another, so we can avoid creating loops by
507 * linking together tiles which are already linked through
510 * This is a disjoint set forest structure: equivalence[i]
511 * contains the index of another member of the equivalence
512 * class containing i, or contains i itself for precisely one
513 * member in each such class. To find a representative member
514 * of the equivalence class containing i, you keep replacing i
515 * with equivalence[i] until it stops changing; then you go
516 * _back_ along the same path and point everything on it
517 * directly at the representative member so as to speed up
518 * future searches. Then you test equivalence between tiles by
519 * finding the representative of each tile and seeing if
520 * they're the same; and you create new equivalence (merge
521 * classes) by finding the representative of each tile and
522 * setting equivalence[one]=the_other.
524 equivalence = snewn(w * h, int);
525 for (i = 0; i < w*h; i++)
526 equivalence[i] = i; /* initially all distinct */
529 * On a non-wrapping grid, we instantly know that all the edges
530 * round the edge are closed.
533 for (i = 0; i < w; i++) {
534 edgestate[i * 5 + 2] = edgestate[((h-1) * w + i) * 5 + 8] = 2;
536 for (i = 0; i < h; i++) {
537 edgestate[(i * w + w-1) * 5 + 1] = edgestate[(i * w) * 5 + 4] = 2;
542 * If we have barriers available, we can mark those edges as
546 for (y = 0; y < h; y++) for (x = 0; x < w; x++) {
548 for (d = 1; d <= 8; d += d) {
549 if (barriers[y*w+x] & d) {
552 * In principle the barrier list should already
553 * contain each barrier from each side, but
554 * let's not take chances with our internal
557 OFFSETWH(x2, y2, x, y, d, w, h);
558 edgestate[(y*w+x) * 5 + d] = 2;
559 edgestate[(y2*w+x2) * 5 + F(d)] = 2;
566 * Since most deductions made by this solver are local (the
567 * exception is loop avoidance, where joining two tiles
568 * together on one side of the grid can theoretically permit a
569 * fresh deduction on the other), we can address the scaling
570 * problem inherent in iterating repeatedly over the entire
571 * grid by instead working with a to-do list.
573 todo = todo_new(w * h);
576 * Main deductive loop.
578 done_something = TRUE; /* prevent instant termination! */
583 * Take a tile index off the todo list and process it.
585 index = todo_get(todo);
588 * If we have run out of immediate things to do, we
589 * have no choice but to scan the whole grid for
590 * longer-range things we've missed. Hence, I now add
591 * every square on the grid back on to the to-do list.
592 * I also set `done_something' to FALSE at this point;
593 * if we later come back here and find it still FALSE,
594 * we will know we've scanned the entire grid without
595 * finding anything new to do, and we can terminate.
599 for (i = 0; i < w*h; i++)
601 done_something = FALSE;
603 index = todo_get(todo);
609 int d, ourclass = dsf_canonify(equivalence, y*w+x);
612 deadendmax[1] = deadendmax[2] = deadendmax[4] = deadendmax[8] = 0;
614 for (i = j = 0; i < 4 && tilestate[(y*w+x) * 4 + i] != 255; i++) {
616 int nnondeadends, nondeadends[4], deadendtotal;
617 int nequiv, equiv[5];
618 int val = tilestate[(y*w+x) * 4 + i];
621 nnondeadends = deadendtotal = 0;
624 for (d = 1; d <= 8; d += d) {
626 * Immediately rule out this orientation if it
627 * conflicts with any known edge.
629 if ((edgestate[(y*w+x) * 5 + d] == 1 && !(val & d)) ||
630 (edgestate[(y*w+x) * 5 + d] == 2 && (val & d)))
635 * Count up the dead-end statistics.
637 if (deadends[(y*w+x) * 5 + d] <= area) {
638 deadendtotal += deadends[(y*w+x) * 5 + d];
640 nondeadends[nnondeadends++] = d;
644 * Ensure we aren't linking to any tiles,
645 * through edges not already known to be
646 * open, which create a loop.
648 if (edgestate[(y*w+x) * 5 + d] == 0) {
651 OFFSETWH(x2, y2, x, y, d, w, h);
652 c = dsf_canonify(equivalence, y2*w+x2);
653 for (k = 0; k < nequiv; k++)
664 if (nnondeadends == 0) {
666 * If this orientation links together dead-ends
667 * with a total area of less than the entire
668 * grid, it is invalid.
670 * (We add 1 to deadendtotal because of the
671 * tile itself, of course; one tile linking
672 * dead ends of size 2 and 3 forms a subnetwork
673 * with a total area of 6, not 5.)
675 if (deadendtotal > 0 && deadendtotal+1 < area)
677 } else if (nnondeadends == 1) {
679 * If this orientation links together one or
680 * more dead-ends with precisely one
681 * non-dead-end, then we may have to mark that
682 * non-dead-end as a dead end going the other
683 * way. However, it depends on whether all
684 * other orientations share the same property.
687 if (deadendmax[nondeadends[0]] < deadendtotal)
688 deadendmax[nondeadends[0]] = deadendtotal;
691 * If this orientation links together two or
692 * more non-dead-ends, then we can rule out the
693 * possibility of putting in new dead-end
694 * markings in those directions.
697 for (k = 0; k < nnondeadends; k++)
698 deadendmax[nondeadends[k]] = area+1;
702 tilestate[(y*w+x) * 4 + j++] = val;
703 #ifdef SOLVER_DIAGNOSTICS
705 printf("ruling out orientation %x at %d,%d\n", val, x, y);
709 assert(j > 0); /* we can't lose _all_ possibilities! */
712 done_something = TRUE;
715 * We have ruled out at least one tile orientation.
716 * Make sure the rest are blanked.
719 tilestate[(y*w+x) * 4 + j++] = 255;
723 * Now go through the tile orientations again and see
724 * if we've deduced anything new about any edges.
730 for (i = 0; i < 4 && tilestate[(y*w+x) * 4 + i] != 255; i++) {
731 a &= tilestate[(y*w+x) * 4 + i];
732 o |= tilestate[(y*w+x) * 4 + i];
734 for (d = 1; d <= 8; d += d)
735 if (edgestate[(y*w+x) * 5 + d] == 0) {
737 OFFSETWH(x2, y2, x, y, d, w, h);
740 /* This edge is open in all orientations. */
741 #ifdef SOLVER_DIAGNOSTICS
742 printf("marking edge %d,%d:%d open\n", x, y, d);
744 edgestate[(y*w+x) * 5 + d] = 1;
745 edgestate[(y2*w+x2) * 5 + d2] = 1;
746 dsf_merge(equivalence, y*w+x, y2*w+x2);
747 done_something = TRUE;
748 todo_add(todo, y2*w+x2);
749 } else if (!(o & d)) {
750 /* This edge is closed in all orientations. */
751 #ifdef SOLVER_DIAGNOSTICS
752 printf("marking edge %d,%d:%d closed\n", x, y, d);
754 edgestate[(y*w+x) * 5 + d] = 2;
755 edgestate[(y2*w+x2) * 5 + d2] = 2;
756 done_something = TRUE;
757 todo_add(todo, y2*w+x2);
764 * Now check the dead-end markers and see if any of
765 * them has lowered from the real ones.
767 for (d = 1; d <= 8; d += d) {
769 OFFSETWH(x2, y2, x, y, d, w, h);
771 if (deadendmax[d] > 0 &&
772 deadends[(y2*w+x2) * 5 + d2] > deadendmax[d]) {
773 #ifdef SOLVER_DIAGNOSTICS
774 printf("setting dead end value %d,%d:%d to %d\n",
775 x2, y2, d2, deadendmax[d]);
777 deadends[(y2*w+x2) * 5 + d2] = deadendmax[d];
778 done_something = TRUE;
779 todo_add(todo, y2*w+x2);
787 * Mark all completely determined tiles as locked.
790 for (i = 0; i < w*h; i++) {
791 if (tilestate[i * 4 + 1] == 255) {
792 assert(tilestate[i * 4 + 0] != 255);
793 tiles[i] = tilestate[i * 4] | LOCKED;
801 * Free up working space.
812 /* ----------------------------------------------------------------------
813 * Randomly select a new game description.
817 * Function to randomly perturb an ambiguous section in a grid, to
818 * attempt to ensure unique solvability.
820 static void perturb(int w, int h, unsigned char *tiles, int wrapping,
821 random_state *rs, int startx, int starty, int startd)
823 struct xyd *perimeter, *perim2, *loop[2], looppos[2];
824 int nperim, perimsize, nloop[2], loopsize[2];
828 * We know that the tile at (startx,starty) is part of an
829 * ambiguous section, and we also know that its neighbour in
830 * direction startd is fully specified. We begin by tracing all
831 * the way round the ambiguous area.
833 nperim = perimsize = 0;
838 #ifdef PERTURB_DIAGNOSTICS
839 printf("perturb %d,%d:%d\n", x, y, d);
844 if (nperim >= perimsize) {
845 perimsize = perimsize * 3 / 2 + 32;
846 perimeter = sresize(perimeter, perimsize, struct xyd);
848 perimeter[nperim].x = x;
849 perimeter[nperim].y = y;
850 perimeter[nperim].direction = d;
852 #ifdef PERTURB_DIAGNOSTICS
853 printf("perimeter: %d,%d:%d\n", x, y, d);
857 * First, see if we can simply turn left from where we are
858 * and find another locked square.
861 OFFSETWH(x2, y2, x, y, d2, w, h);
862 if ((!wrapping && (abs(x2-x) > 1 || abs(y2-y) > 1)) ||
863 (tiles[y2*w+x2] & LOCKED)) {
867 * Failing that, step left into the new square and look
872 OFFSETWH(x2, y2, x, y, d, w, h);
873 if ((wrapping || (abs(x2-x) <= 1 && abs(y2-y) <= 1)) &&
874 !(tiles[y2*w+x2] & LOCKED)) {
876 * And failing _that_, we're going to have to step
877 * forward into _that_ square and look right at the
878 * same locked square as we started with.
886 } while (x != startx || y != starty || d != startd);
889 * Our technique for perturbing this ambiguous area is to
890 * search round its edge for a join we can make: that is, an
891 * edge on the perimeter which is (a) not currently connected,
892 * and (b) connecting it would not yield a full cross on either
893 * side. Then we make that join, search round the network to
894 * find the loop thus constructed, and sever the loop at a
895 * randomly selected other point.
897 perim2 = snewn(nperim, struct xyd);
898 memcpy(perim2, perimeter, nperim * sizeof(struct xyd));
899 /* Shuffle the perimeter, so as to search it without directional bias. */
900 shuffle(perim2, nperim, sizeof(*perim2), rs);
901 for (i = 0; i < nperim; i++) {
906 d = perim2[i].direction;
908 OFFSETWH(x2, y2, x, y, d, w, h);
909 if (!wrapping && (abs(x2-x) > 1 || abs(y2-y) > 1))
910 continue; /* can't link across non-wrapping border */
911 if (tiles[y*w+x] & d)
912 continue; /* already linked in this direction! */
913 if (((tiles[y*w+x] | d) & 15) == 15)
914 continue; /* can't turn this tile into a cross */
915 if (((tiles[y2*w+x2] | F(d)) & 15) == 15)
916 continue; /* can't turn other tile into a cross */
919 * We've found the point at which we're going to make a new
922 #ifdef PERTURB_DIAGNOSTICS
923 printf("linking %d,%d:%d\n", x, y, d);
926 tiles[y2*w+x2] |= F(d);
933 return; /* nothing we can do! */
936 * Now we've constructed a new link, we need to find the entire
937 * loop of which it is a part.
939 * In principle, this involves doing a complete search round
940 * the network. However, I anticipate that in the vast majority
941 * of cases the loop will be quite small, so what I'm going to
942 * do is make _two_ searches round the network in parallel, one
943 * keeping its metaphorical hand on the left-hand wall while
944 * the other keeps its hand on the right. As soon as one of
945 * them gets back to its starting point, I abandon the other.
947 for (i = 0; i < 2; i++) {
948 loopsize[i] = nloop[i] = 0;
952 looppos[i].direction = d;
955 for (i = 0; i < 2; i++) {
960 d = looppos[i].direction;
962 OFFSETWH(x2, y2, x, y, d, w, h);
965 * Add this path segment to the loop, unless it exactly
966 * reverses the previous one on the loop in which case
967 * we take it away again.
969 #ifdef PERTURB_DIAGNOSTICS
970 printf("looppos[%d] = %d,%d:%d\n", i, x, y, d);
973 loop[i][nloop[i]-1].x == x2 &&
974 loop[i][nloop[i]-1].y == y2 &&
975 loop[i][nloop[i]-1].direction == F(d)) {
976 #ifdef PERTURB_DIAGNOSTICS
977 printf("removing path segment %d,%d:%d from loop[%d]\n",
982 if (nloop[i] >= loopsize[i]) {
983 loopsize[i] = loopsize[i] * 3 / 2 + 32;
984 loop[i] = sresize(loop[i], loopsize[i], struct xyd);
986 #ifdef PERTURB_DIAGNOSTICS
987 printf("adding path segment %d,%d:%d to loop[%d]\n",
990 loop[i][nloop[i]++] = looppos[i];
993 #ifdef PERTURB_DIAGNOSTICS
994 printf("tile at new location is %x\n", tiles[y2*w+x2] & 0xF);
997 for (j = 0; j < 4; j++) {
1002 #ifdef PERTURB_DIAGNOSTICS
1003 printf("trying dir %d\n", d);
1005 if (tiles[y2*w+x2] & d) {
1008 looppos[i].direction = d;
1014 assert(nloop[i] > 0);
1016 if (looppos[i].x == loop[i][0].x &&
1017 looppos[i].y == loop[i][0].y &&
1018 looppos[i].direction == loop[i][0].direction) {
1019 #ifdef PERTURB_DIAGNOSTICS
1020 printf("loop %d finished tracking\n", i);
1024 * Having found our loop, we now sever it at a
1025 * randomly chosen point - absolutely any will do -
1026 * which is not the one we joined it at to begin
1027 * with. Conveniently, the one we joined it at is
1028 * loop[i][0], so we just avoid that one.
1030 j = random_upto(rs, nloop[i]-1) + 1;
1033 d = loop[i][j].direction;
1034 OFFSETWH(x2, y2, x, y, d, w, h);
1036 tiles[y2*w+x2] &= ~F(d);
1048 * Finally, we must mark the entire disputed section as locked,
1049 * to prevent the perturb function being called on it multiple
1052 * To do this, we _sort_ the perimeter of the area. The
1053 * existing xyd_cmp function will arrange things into columns
1054 * for us, in such a way that each column has the edges in
1055 * vertical order. Then we can work down each column and fill
1056 * in all the squares between an up edge and a down edge.
1058 qsort(perimeter, nperim, sizeof(struct xyd), xyd_cmp);
1060 for (i = 0; i <= nperim; i++) {
1061 if (i == nperim || perimeter[i].x > x) {
1063 * Fill in everything from the last Up edge to the
1064 * bottom of the grid, if necessary.
1068 #ifdef PERTURB_DIAGNOSTICS
1069 printf("resolved: locking tile %d,%d\n", x, y);
1071 tiles[y * w + x] |= LOCKED;
1084 if (perimeter[i].direction == U) {
1087 } else if (perimeter[i].direction == D) {
1089 * Fill in everything from the last Up edge to here.
1091 assert(x == perimeter[i].x && y <= perimeter[i].y);
1092 while (y <= perimeter[i].y) {
1093 #ifdef PERTURB_DIAGNOSTICS
1094 printf("resolved: locking tile %d,%d\n", x, y);
1096 tiles[y * w + x] |= LOCKED;
1106 static char *new_game_desc(game_params *params, random_state *rs,
1107 char **aux, int interactive)
1109 tree234 *possibilities, *barriertree;
1110 int w, h, x, y, cx, cy, nbarriers;
1111 unsigned char *tiles, *barriers;
1120 tiles = snewn(w * h, unsigned char);
1121 barriers = snewn(w * h, unsigned char);
1125 memset(tiles, 0, w * h);
1126 memset(barriers, 0, w * h);
1129 * Construct the unshuffled grid.
1131 * To do this, we simply start at the centre point, repeatedly
1132 * choose a random possibility out of the available ways to
1133 * extend a used square into an unused one, and do it. After
1134 * extending the third line out of a square, we remove the
1135 * fourth from the possibilities list to avoid any full-cross
1136 * squares (which would make the game too easy because they
1137 * only have one orientation).
1139 * The slightly worrying thing is the avoidance of full-cross
1140 * squares. Can this cause our unsophisticated construction
1141 * algorithm to paint itself into a corner, by getting into a
1142 * situation where there are some unreached squares and the
1143 * only way to reach any of them is to extend a T-piece into a
1146 * Answer: no it can't, and here's a proof.
1148 * Any contiguous group of such unreachable squares must be
1149 * surrounded on _all_ sides by T-pieces pointing away from the
1150 * group. (If not, then there is a square which can be extended
1151 * into one of the `unreachable' ones, and so it wasn't
1152 * unreachable after all.) In particular, this implies that
1153 * each contiguous group of unreachable squares must be
1154 * rectangular in shape (any deviation from that yields a
1155 * non-T-piece next to an `unreachable' square).
1157 * So we have a rectangle of unreachable squares, with T-pieces
1158 * forming a solid border around the rectangle. The corners of
1159 * that border must be connected (since every tile connects all
1160 * the lines arriving in it), and therefore the border must
1161 * form a closed loop around the rectangle.
1163 * But this can't have happened in the first place, since we
1164 * _know_ we've avoided creating closed loops! Hence, no such
1165 * situation can ever arise, and the naive grid construction
1166 * algorithm will guaranteeably result in a complete grid
1167 * containing no unreached squares, no full crosses _and_ no
1170 possibilities = newtree234(xyd_cmp_nc);
1173 add234(possibilities, new_xyd(cx, cy, R));
1175 add234(possibilities, new_xyd(cx, cy, U));
1177 add234(possibilities, new_xyd(cx, cy, L));
1179 add234(possibilities, new_xyd(cx, cy, D));
1181 while (count234(possibilities) > 0) {
1184 int x1, y1, d1, x2, y2, d2, d;
1187 * Extract a randomly chosen possibility from the list.
1189 i = random_upto(rs, count234(possibilities));
1190 xyd = delpos234(possibilities, i);
1193 d1 = xyd->direction;
1196 OFFSET(x2, y2, x1, y1, d1, params);
1198 #ifdef GENERATION_DIAGNOSTICS
1199 printf("picked (%d,%d,%c) <-> (%d,%d,%c)\n",
1200 x1, y1, "0RU3L567D9abcdef"[d1], x2, y2, "0RU3L567D9abcdef"[d2]);
1204 * Make the connection. (We should be moving to an as yet
1207 index(params, tiles, x1, y1) |= d1;
1208 assert(index(params, tiles, x2, y2) == 0);
1209 index(params, tiles, x2, y2) |= d2;
1212 * If we have created a T-piece, remove its last
1215 if (COUNT(index(params, tiles, x1, y1)) == 3) {
1216 struct xyd xyd1, *xydp;
1220 xyd1.direction = 0x0F ^ index(params, tiles, x1, y1);
1222 xydp = find234(possibilities, &xyd1, NULL);
1225 #ifdef GENERATION_DIAGNOSTICS
1226 printf("T-piece; removing (%d,%d,%c)\n",
1227 xydp->x, xydp->y, "0RU3L567D9abcdef"[xydp->direction]);
1229 del234(possibilities, xydp);
1235 * Remove all other possibilities that were pointing at the
1236 * tile we've just moved into.
1238 for (d = 1; d < 0x10; d <<= 1) {
1240 struct xyd xyd1, *xydp;
1242 OFFSET(x3, y3, x2, y2, d, params);
1247 xyd1.direction = d3;
1249 xydp = find234(possibilities, &xyd1, NULL);
1252 #ifdef GENERATION_DIAGNOSTICS
1253 printf("Loop avoidance; removing (%d,%d,%c)\n",
1254 xydp->x, xydp->y, "0RU3L567D9abcdef"[xydp->direction]);
1256 del234(possibilities, xydp);
1262 * Add new possibilities to the list for moving _out_ of
1263 * the tile we have just moved into.
1265 for (d = 1; d < 0x10; d <<= 1) {
1269 continue; /* we've got this one already */
1271 if (!params->wrapping) {
1272 if (d == U && y2 == 0)
1274 if (d == D && y2 == h-1)
1276 if (d == L && x2 == 0)
1278 if (d == R && x2 == w-1)
1282 OFFSET(x3, y3, x2, y2, d, params);
1284 if (index(params, tiles, x3, y3))
1285 continue; /* this would create a loop */
1287 #ifdef GENERATION_DIAGNOSTICS
1288 printf("New frontier; adding (%d,%d,%c)\n",
1289 x2, y2, "0RU3L567D9abcdef"[d]);
1291 add234(possibilities, new_xyd(x2, y2, d));
1294 /* Having done that, we should have no possibilities remaining. */
1295 assert(count234(possibilities) == 0);
1296 freetree234(possibilities);
1298 if (params->unique) {
1302 * Run the solver to check unique solubility.
1304 while (!net_solver(w, h, tiles, NULL, params->wrapping)) {
1308 * We expect (in most cases) that most of the grid will
1309 * be uniquely specified already, and the remaining
1310 * ambiguous sections will be small and separate. So
1311 * our strategy is to find each individual such
1312 * section, and perform a perturbation on the network
1315 for (y = 0; y < h; y++) for (x = 0; x < w; x++) {
1316 if (x+1 < w && ((tiles[y*w+x] ^ tiles[y*w+x+1]) & LOCKED)) {
1318 if (tiles[y*w+x] & LOCKED)
1319 perturb(w, h, tiles, params->wrapping, rs, x+1, y, L);
1321 perturb(w, h, tiles, params->wrapping, rs, x, y, R);
1323 if (y+1 < h && ((tiles[y*w+x] ^ tiles[(y+1)*w+x]) & LOCKED)) {
1325 if (tiles[y*w+x] & LOCKED)
1326 perturb(w, h, tiles, params->wrapping, rs, x, y+1, U);
1328 perturb(w, h, tiles, params->wrapping, rs, x, y, D);
1333 * Now n counts the number of ambiguous sections we
1334 * have fiddled with. If we haven't managed to decrease
1335 * it from the last time we ran the solver, give up and
1336 * regenerate the entire grid.
1338 if (prevn != -1 && prevn <= n)
1339 goto begin_generation; /* (sorry) */
1345 * The solver will have left a lot of LOCKED bits lying
1346 * around in the tiles array. Remove them.
1348 for (x = 0; x < w*h; x++)
1349 tiles[x] &= ~LOCKED;
1353 * Now compute a list of the possible barrier locations.
1355 barriertree = newtree234(xyd_cmp_nc);
1356 for (y = 0; y < h; y++) {
1357 for (x = 0; x < w; x++) {
1359 if (!(index(params, tiles, x, y) & R) &&
1360 (params->wrapping || x < w-1))
1361 add234(barriertree, new_xyd(x, y, R));
1362 if (!(index(params, tiles, x, y) & D) &&
1363 (params->wrapping || y < h-1))
1364 add234(barriertree, new_xyd(x, y, D));
1369 * Save the unshuffled grid in aux.
1375 solution = snewn(w * h + 1, char);
1376 for (i = 0; i < w * h; i++)
1377 solution[i] = "0123456789abcdef"[tiles[i] & 0xF];
1378 solution[w*h] = '\0';
1384 * Now shuffle the grid.
1386 for (y = 0; y < h; y++) {
1387 for (x = 0; x < w; x++) {
1388 int orig = index(params, tiles, x, y);
1389 int rot = random_upto(rs, 4);
1390 index(params, tiles, x, y) = ROT(orig, rot);
1395 * And now choose barrier locations. (We carefully do this
1396 * _after_ shuffling, so that changing the barrier rate in the
1397 * params while keeping the random seed the same will give the
1398 * same shuffled grid and _only_ change the barrier locations.
1399 * Also the way we choose barrier locations, by repeatedly
1400 * choosing one possibility from the list until we have enough,
1401 * is designed to ensure that raising the barrier rate while
1402 * keeping the seed the same will provide a superset of the
1403 * previous barrier set - i.e. if you ask for 10 barriers, and
1404 * then decide that's still too hard and ask for 20, you'll get
1405 * the original 10 plus 10 more, rather than getting 20 new
1406 * ones and the chance of remembering your first 10.)
1408 nbarriers = (int)(params->barrier_probability * count234(barriertree));
1409 assert(nbarriers >= 0 && nbarriers <= count234(barriertree));
1411 while (nbarriers > 0) {
1414 int x1, y1, d1, x2, y2, d2;
1417 * Extract a randomly chosen barrier from the list.
1419 i = random_upto(rs, count234(barriertree));
1420 xyd = delpos234(barriertree, i);
1422 assert(xyd != NULL);
1426 d1 = xyd->direction;
1429 OFFSET(x2, y2, x1, y1, d1, params);
1432 index(params, barriers, x1, y1) |= d1;
1433 index(params, barriers, x2, y2) |= d2;
1439 * Clean up the rest of the barrier list.
1444 while ( (xyd = delpos234(barriertree, 0)) != NULL)
1447 freetree234(barriertree);
1451 * Finally, encode the grid into a string game description.
1453 * My syntax is extremely simple: each square is encoded as a
1454 * hex digit in which bit 0 means a connection on the right,
1455 * bit 1 means up, bit 2 left and bit 3 down. (i.e. the same
1456 * encoding as used internally). Each digit is followed by
1457 * optional barrier indicators: `v' means a vertical barrier to
1458 * the right of it, and `h' means a horizontal barrier below
1461 desc = snewn(w * h * 3 + 1, char);
1463 for (y = 0; y < h; y++) {
1464 for (x = 0; x < w; x++) {
1465 *p++ = "0123456789abcdef"[index(params, tiles, x, y)];
1466 if ((params->wrapping || x < w-1) &&
1467 (index(params, barriers, x, y) & R))
1469 if ((params->wrapping || y < h-1) &&
1470 (index(params, barriers, x, y) & D))
1474 assert(p - desc <= w*h*3);
1483 static char *validate_desc(game_params *params, char *desc)
1485 int w = params->width, h = params->height;
1488 for (i = 0; i < w*h; i++) {
1489 if (*desc >= '0' && *desc <= '9')
1491 else if (*desc >= 'a' && *desc <= 'f')
1493 else if (*desc >= 'A' && *desc <= 'F')
1496 return "Game description shorter than expected";
1498 return "Game description contained unexpected character";
1500 while (*desc == 'h' || *desc == 'v')
1504 return "Game description longer than expected";
1509 /* ----------------------------------------------------------------------
1510 * Construct an initial game state, given a description and parameters.
1513 static game_state *new_game(midend *me, game_params *params, char *desc)
1518 assert(params->width > 0 && params->height > 0);
1519 assert(params->width > 1 || params->height > 1);
1522 * Create a blank game state.
1524 state = snew(game_state);
1525 w = state->width = params->width;
1526 h = state->height = params->height;
1527 state->wrapping = params->wrapping;
1528 state->last_rotate_dir = state->last_rotate_x = state->last_rotate_y = 0;
1529 state->completed = state->used_solve = FALSE;
1530 state->tiles = snewn(state->width * state->height, unsigned char);
1531 memset(state->tiles, 0, state->width * state->height);
1532 state->barriers = snewn(state->width * state->height, unsigned char);
1533 memset(state->barriers, 0, state->width * state->height);
1536 * Parse the game description into the grid.
1538 for (y = 0; y < h; y++) {
1539 for (x = 0; x < w; x++) {
1540 if (*desc >= '0' && *desc <= '9')
1541 tile(state, x, y) = *desc - '0';
1542 else if (*desc >= 'a' && *desc <= 'f')
1543 tile(state, x, y) = *desc - 'a' + 10;
1544 else if (*desc >= 'A' && *desc <= 'F')
1545 tile(state, x, y) = *desc - 'A' + 10;
1548 while (*desc == 'h' || *desc == 'v') {
1555 OFFSET(x2, y2, x, y, d1, state);
1558 barrier(state, x, y) |= d1;
1559 barrier(state, x2, y2) |= d2;
1567 * Set up border barriers if this is a non-wrapping game.
1569 if (!state->wrapping) {
1570 for (x = 0; x < state->width; x++) {
1571 barrier(state, x, 0) |= U;
1572 barrier(state, x, state->height-1) |= D;
1574 for (y = 0; y < state->height; y++) {
1575 barrier(state, 0, y) |= L;
1576 barrier(state, state->width-1, y) |= R;
1580 * We check whether this is de-facto a non-wrapping game
1581 * despite the parameters, in case we were passed the
1582 * description of a non-wrapping game. This is so that we
1583 * can change some aspects of the UI behaviour.
1585 state->wrapping = FALSE;
1586 for (x = 0; x < state->width; x++)
1587 if (!(barrier(state, x, 0) & U) ||
1588 !(barrier(state, x, state->height-1) & D))
1589 state->wrapping = TRUE;
1590 for (y = 0; y < state->width; y++)
1591 if (!(barrier(state, 0, y) & L) ||
1592 !(barrier(state, state->width-1, y) & R))
1593 state->wrapping = TRUE;
1599 static game_state *dup_game(game_state *state)
1603 ret = snew(game_state);
1604 ret->width = state->width;
1605 ret->height = state->height;
1606 ret->wrapping = state->wrapping;
1607 ret->completed = state->completed;
1608 ret->used_solve = state->used_solve;
1609 ret->last_rotate_dir = state->last_rotate_dir;
1610 ret->last_rotate_x = state->last_rotate_x;
1611 ret->last_rotate_y = state->last_rotate_y;
1612 ret->tiles = snewn(state->width * state->height, unsigned char);
1613 memcpy(ret->tiles, state->tiles, state->width * state->height);
1614 ret->barriers = snewn(state->width * state->height, unsigned char);
1615 memcpy(ret->barriers, state->barriers, state->width * state->height);
1620 static void free_game(game_state *state)
1622 sfree(state->tiles);
1623 sfree(state->barriers);
1627 static char *solve_game(game_state *state, game_state *currstate,
1628 char *aux, char **error)
1630 unsigned char *tiles;
1632 int retlen, retsize;
1635 tiles = snewn(state->width * state->height, unsigned char);
1639 * Run the internal solver on the provided grid. This might
1640 * not yield a complete solution.
1642 memcpy(tiles, state->tiles, state->width * state->height);
1643 net_solver(state->width, state->height, tiles,
1644 state->barriers, state->wrapping);
1646 for (i = 0; i < state->width * state->height; i++) {
1649 if (c >= '0' && c <= '9')
1651 else if (c >= 'a' && c <= 'f')
1652 tiles[i] = c - 'a' + 10;
1653 else if (c >= 'A' && c <= 'F')
1654 tiles[i] = c - 'A' + 10;
1661 * Now construct a string which can be passed to execute_move()
1662 * to transform the current grid into the solved one.
1665 ret = snewn(retsize, char);
1667 ret[retlen++] = 'S';
1669 for (i = 0; i < state->width * state->height; i++) {
1670 int from = currstate->tiles[i], to = tiles[i];
1671 int ft = from & (R|L|U|D), tt = to & (R|L|U|D);
1672 int x = i % state->width, y = i / state->width;
1674 char buf[80], *p = buf;
1677 continue; /* nothing needs doing at all */
1680 * To transform this tile into the desired tile: first
1681 * unlock the tile if it's locked, then rotate it if
1682 * necessary, then lock it if necessary.
1685 p += sprintf(p, ";L%d,%d", x, y);
1689 else if (tt == C(ft))
1691 else if (tt == F(ft))
1698 p += sprintf(p, ";%c%d,%d", chr, x, y);
1701 p += sprintf(p, ";L%d,%d", x, y);
1704 if (retlen + (p - buf) >= retsize) {
1705 retsize = retlen + (p - buf) + 512;
1706 ret = sresize(ret, retsize, char);
1708 memcpy(ret+retlen, buf, p - buf);
1713 assert(retlen < retsize);
1715 ret = sresize(ret, retlen+1, char);
1722 static char *game_text_format(game_state *state)
1727 /* ----------------------------------------------------------------------
1732 * Compute which squares are reachable from the centre square, as a
1733 * quick visual aid to determining how close the game is to
1734 * completion. This is also a simple way to tell if the game _is_
1735 * completed - just call this function and see whether every square
1738 static unsigned char *compute_active(game_state *state, int cx, int cy)
1740 unsigned char *active;
1744 active = snewn(state->width * state->height, unsigned char);
1745 memset(active, 0, state->width * state->height);
1748 * We only store (x,y) pairs in todo, but it's easier to reuse
1749 * xyd_cmp and just store direction 0 every time.
1751 todo = newtree234(xyd_cmp_nc);
1752 index(state, active, cx, cy) = ACTIVE;
1753 add234(todo, new_xyd(cx, cy, 0));
1755 while ( (xyd = delpos234(todo, 0)) != NULL) {
1756 int x1, y1, d1, x2, y2, d2;
1762 for (d1 = 1; d1 < 0x10; d1 <<= 1) {
1763 OFFSET(x2, y2, x1, y1, d1, state);
1767 * If the next tile in this direction is connected to
1768 * us, and there isn't a barrier in the way, and it
1769 * isn't already marked active, then mark it active and
1770 * add it to the to-examine list.
1772 if ((tile(state, x1, y1) & d1) &&
1773 (tile(state, x2, y2) & d2) &&
1774 !(barrier(state, x1, y1) & d1) &&
1775 !index(state, active, x2, y2)) {
1776 index(state, active, x2, y2) = ACTIVE;
1777 add234(todo, new_xyd(x2, y2, 0));
1781 /* Now we expect the todo list to have shrunk to zero size. */
1782 assert(count234(todo) == 0);
1789 int org_x, org_y; /* origin */
1790 int cx, cy; /* source tile (game coordinates) */
1793 random_state *rs; /* used for jumbling */
1796 static game_ui *new_ui(game_state *state)
1800 game_ui *ui = snew(game_ui);
1801 ui->org_x = ui->org_y = 0;
1802 ui->cur_x = ui->cx = state->width / 2;
1803 ui->cur_y = ui->cy = state->height / 2;
1804 ui->cur_visible = FALSE;
1805 get_random_seed(&seed, &seedsize);
1806 ui->rs = random_new(seed, seedsize);
1812 static void free_ui(game_ui *ui)
1814 random_free(ui->rs);
1818 static char *encode_ui(game_ui *ui)
1822 * We preserve the origin and centre-point coordinates over a
1825 sprintf(buf, "O%d,%d;C%d,%d", ui->org_x, ui->org_y, ui->cx, ui->cy);
1829 static void decode_ui(game_ui *ui, char *encoding)
1831 sscanf(encoding, "O%d,%d;C%d,%d",
1832 &ui->org_x, &ui->org_y, &ui->cx, &ui->cy);
1835 static void game_changed_state(game_ui *ui, game_state *oldstate,
1836 game_state *newstate)
1840 struct game_drawstate {
1845 unsigned char *visible;
1848 /* ----------------------------------------------------------------------
1851 static char *interpret_move(game_state *state, game_ui *ui,
1852 game_drawstate *ds, int x, int y, int button)
1855 int tx = -1, ty = -1, dir = 0;
1856 int shift = button & MOD_SHFT, ctrl = button & MOD_CTRL;
1858 NONE, ROTATE_LEFT, ROTATE_180, ROTATE_RIGHT, TOGGLE_LOCK, JUMBLE,
1859 MOVE_ORIGIN, MOVE_SOURCE, MOVE_ORIGIN_AND_SOURCE, MOVE_CURSOR
1862 button &= ~MOD_MASK;
1866 if (button == LEFT_BUTTON ||
1867 button == MIDDLE_BUTTON ||
1868 button == RIGHT_BUTTON) {
1870 if (ui->cur_visible) {
1871 ui->cur_visible = FALSE;
1876 * The button must have been clicked on a valid tile.
1878 x -= WINDOW_OFFSET + TILE_BORDER;
1879 y -= WINDOW_OFFSET + TILE_BORDER;
1884 if (tx >= state->width || ty >= state->height)
1886 /* Transform from physical to game coords */
1887 tx = (tx + ui->org_x) % state->width;
1888 ty = (ty + ui->org_y) % state->height;
1889 if (x % TILE_SIZE >= TILE_SIZE - TILE_BORDER ||
1890 y % TILE_SIZE >= TILE_SIZE - TILE_BORDER)
1893 action = button == LEFT_BUTTON ? ROTATE_LEFT :
1894 button == RIGHT_BUTTON ? ROTATE_RIGHT : TOGGLE_LOCK;
1895 } else if (button == CURSOR_UP || button == CURSOR_DOWN ||
1896 button == CURSOR_RIGHT || button == CURSOR_LEFT) {
1898 case CURSOR_UP: dir = U; break;
1899 case CURSOR_DOWN: dir = D; break;
1900 case CURSOR_LEFT: dir = L; break;
1901 case CURSOR_RIGHT: dir = R; break;
1902 default: return nullret;
1904 if (shift && ctrl) action = MOVE_ORIGIN_AND_SOURCE;
1905 else if (shift) action = MOVE_ORIGIN;
1906 else if (ctrl) action = MOVE_SOURCE;
1907 else action = MOVE_CURSOR;
1908 } else if (button == 'a' || button == 's' || button == 'd' ||
1909 button == 'A' || button == 'S' || button == 'D' ||
1910 button == 'f' || button == 'F' ||
1911 button == CURSOR_SELECT) {
1914 if (button == 'a' || button == 'A' || button == CURSOR_SELECT)
1915 action = ROTATE_LEFT;
1916 else if (button == 's' || button == 'S')
1917 action = TOGGLE_LOCK;
1918 else if (button == 'd' || button == 'D')
1919 action = ROTATE_RIGHT;
1920 else if (button == 'f' || button == 'F')
1921 action = ROTATE_180;
1922 ui->cur_visible = TRUE;
1923 } else if (button == 'j' || button == 'J') {
1924 /* XXX should we have some mouse control for this? */
1930 * The middle button locks or unlocks a tile. (A locked tile
1931 * cannot be turned, and is visually marked as being locked.
1932 * This is a convenience for the player, so that once they are
1933 * sure which way round a tile goes, they can lock it and thus
1934 * avoid forgetting later on that they'd already done that one;
1935 * and the locking also prevents them turning the tile by
1936 * accident. If they change their mind, another middle click
1939 if (action == TOGGLE_LOCK) {
1941 sprintf(buf, "L%d,%d", tx, ty);
1943 } else if (action == ROTATE_LEFT || action == ROTATE_RIGHT ||
1944 action == ROTATE_180) {
1948 * The left and right buttons have no effect if clicked on a
1951 if (tile(state, tx, ty) & LOCKED)
1955 * Otherwise, turn the tile one way or the other. Left button
1956 * turns anticlockwise; right button turns clockwise.
1958 sprintf(buf, "%c%d,%d", (int)(action == ROTATE_LEFT ? 'A' :
1959 action == ROTATE_RIGHT ? 'C' : 'F'), tx, ty);
1961 } else if (action == JUMBLE) {
1963 * Jumble all unlocked tiles to random orientations.
1970 * Maximum string length assumes no int can be converted to
1971 * decimal and take more than 11 digits!
1973 maxlen = state->width * state->height * 25 + 3;
1975 ret = snewn(maxlen, char);
1979 for (jy = 0; jy < state->height; jy++) {
1980 for (jx = 0; jx < state->width; jx++) {
1981 if (!(tile(state, jx, jy) & LOCKED)) {
1982 int rot = random_upto(ui->rs, 4);
1984 p += sprintf(p, ";%c%d,%d", "AFC"[rot-1], jx, jy);
1990 assert(p - ret < maxlen);
1991 ret = sresize(ret, p - ret, char);
1994 } else if (action == MOVE_ORIGIN || action == MOVE_SOURCE ||
1995 action == MOVE_ORIGIN_AND_SOURCE || action == MOVE_CURSOR) {
1997 if (action == MOVE_ORIGIN || action == MOVE_ORIGIN_AND_SOURCE) {
1998 if (state->wrapping) {
1999 OFFSET(ui->org_x, ui->org_y, ui->org_x, ui->org_y, dir, state);
2000 } else return nullret; /* disallowed for non-wrapping grids */
2002 if (action == MOVE_SOURCE || action == MOVE_ORIGIN_AND_SOURCE) {
2003 OFFSET(ui->cx, ui->cy, ui->cx, ui->cy, dir, state);
2005 if (action == MOVE_CURSOR) {
2006 OFFSET(ui->cur_x, ui->cur_y, ui->cur_x, ui->cur_y, dir, state);
2007 ui->cur_visible = TRUE;
2015 static game_state *execute_move(game_state *from, char *move)
2018 int tx, ty, n, noanim, orig;
2020 ret = dup_game(from);
2022 if (move[0] == 'J' || move[0] == 'S') {
2024 ret->used_solve = TRUE;
2033 ret->last_rotate_dir = 0; /* suppress animation */
2034 ret->last_rotate_x = ret->last_rotate_y = 0;
2037 if ((move[0] == 'A' || move[0] == 'C' ||
2038 move[0] == 'F' || move[0] == 'L') &&
2039 sscanf(move+1, "%d,%d%n", &tx, &ty, &n) >= 2 &&
2040 tx >= 0 && tx < from->width && ty >= 0 && ty < from->height) {
2041 orig = tile(ret, tx, ty);
2042 if (move[0] == 'A') {
2043 tile(ret, tx, ty) = A(orig);
2045 ret->last_rotate_dir = +1;
2046 } else if (move[0] == 'F') {
2047 tile(ret, tx, ty) = F(orig);
2049 ret->last_rotate_dir = +2; /* + for sake of argument */
2050 } else if (move[0] == 'C') {
2051 tile(ret, tx, ty) = C(orig);
2053 ret->last_rotate_dir = -1;
2055 assert(move[0] == 'L');
2056 tile(ret, tx, ty) ^= LOCKED;
2060 if (*move == ';') move++;
2067 ret->last_rotate_x = tx;
2068 ret->last_rotate_y = ty;
2072 * Check whether the game has been completed.
2074 * For this purpose it doesn't matter where the source square
2075 * is, because we can start from anywhere and correctly
2076 * determine whether the game is completed.
2079 unsigned char *active = compute_active(ret, 0, 0);
2081 int complete = TRUE;
2083 for (x1 = 0; x1 < ret->width; x1++)
2084 for (y1 = 0; y1 < ret->height; y1++)
2085 if ((tile(ret, x1, y1) & 0xF) && !index(ret, active, x1, y1)) {
2087 goto break_label; /* break out of two loops at once */
2094 ret->completed = TRUE;
2101 /* ----------------------------------------------------------------------
2102 * Routines for drawing the game position on the screen.
2105 static game_drawstate *game_new_drawstate(drawing *dr, game_state *state)
2107 game_drawstate *ds = snew(game_drawstate);
2109 ds->started = FALSE;
2110 ds->width = state->width;
2111 ds->height = state->height;
2112 ds->org_x = ds->org_y = -1;
2113 ds->visible = snewn(state->width * state->height, unsigned char);
2114 ds->tilesize = 0; /* undecided yet */
2115 memset(ds->visible, 0xFF, state->width * state->height);
2120 static void game_free_drawstate(drawing *dr, game_drawstate *ds)
2126 static void game_compute_size(game_params *params, int tilesize,
2129 *x = WINDOW_OFFSET * 2 + tilesize * params->width + TILE_BORDER;
2130 *y = WINDOW_OFFSET * 2 + tilesize * params->height + TILE_BORDER;
2133 static void game_set_size(drawing *dr, game_drawstate *ds,
2134 game_params *params, int tilesize)
2136 ds->tilesize = tilesize;
2139 static float *game_colours(frontend *fe, int *ncolours)
2143 ret = snewn(NCOLOURS * 3, float);
2144 *ncolours = NCOLOURS;
2147 * Basic background colour is whatever the front end thinks is
2148 * a sensible default.
2150 frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
2155 ret[COL_WIRE * 3 + 0] = 0.0F;
2156 ret[COL_WIRE * 3 + 1] = 0.0F;
2157 ret[COL_WIRE * 3 + 2] = 0.0F;
2160 * Powered wires and powered endpoints are cyan.
2162 ret[COL_POWERED * 3 + 0] = 0.0F;
2163 ret[COL_POWERED * 3 + 1] = 1.0F;
2164 ret[COL_POWERED * 3 + 2] = 1.0F;
2169 ret[COL_BARRIER * 3 + 0] = 1.0F;
2170 ret[COL_BARRIER * 3 + 1] = 0.0F;
2171 ret[COL_BARRIER * 3 + 2] = 0.0F;
2174 * Unpowered endpoints are blue.
2176 ret[COL_ENDPOINT * 3 + 0] = 0.0F;
2177 ret[COL_ENDPOINT * 3 + 1] = 0.0F;
2178 ret[COL_ENDPOINT * 3 + 2] = 1.0F;
2181 * Tile borders are a darker grey than the background.
2183 ret[COL_BORDER * 3 + 0] = 0.5F * ret[COL_BACKGROUND * 3 + 0];
2184 ret[COL_BORDER * 3 + 1] = 0.5F * ret[COL_BACKGROUND * 3 + 1];
2185 ret[COL_BORDER * 3 + 2] = 0.5F * ret[COL_BACKGROUND * 3 + 2];
2188 * Locked tiles are a grey in between those two.
2190 ret[COL_LOCKED * 3 + 0] = 0.75F * ret[COL_BACKGROUND * 3 + 0];
2191 ret[COL_LOCKED * 3 + 1] = 0.75F * ret[COL_BACKGROUND * 3 + 1];
2192 ret[COL_LOCKED * 3 + 2] = 0.75F * ret[COL_BACKGROUND * 3 + 2];
2197 static void draw_thick_line(drawing *dr, int x1, int y1, int x2, int y2,
2200 draw_line(dr, x1-1, y1, x2-1, y2, COL_WIRE);
2201 draw_line(dr, x1+1, y1, x2+1, y2, COL_WIRE);
2202 draw_line(dr, x1, y1-1, x2, y2-1, COL_WIRE);
2203 draw_line(dr, x1, y1+1, x2, y2+1, COL_WIRE);
2204 draw_line(dr, x1, y1, x2, y2, colour);
2207 static void draw_rect_coords(drawing *dr, int x1, int y1, int x2, int y2,
2210 int mx = (x1 < x2 ? x1 : x2);
2211 int my = (y1 < y2 ? y1 : y2);
2212 int dx = (x2 + x1 - 2*mx + 1);
2213 int dy = (y2 + y1 - 2*my + 1);
2215 draw_rect(dr, mx, my, dx, dy, colour);
2219 * draw_barrier_corner() and draw_barrier() are passed physical coords
2221 static void draw_barrier_corner(drawing *dr, game_drawstate *ds,
2222 int x, int y, int dx, int dy, int phase)
2224 int bx = WINDOW_OFFSET + TILE_SIZE * x;
2225 int by = WINDOW_OFFSET + TILE_SIZE * y;
2228 x1 = (dx > 0 ? TILE_SIZE+TILE_BORDER-1 : 0);
2229 y1 = (dy > 0 ? TILE_SIZE+TILE_BORDER-1 : 0);
2232 draw_rect_coords(dr, bx+x1+dx, by+y1,
2233 bx+x1-TILE_BORDER*dx, by+y1-(TILE_BORDER-1)*dy,
2235 draw_rect_coords(dr, bx+x1, by+y1+dy,
2236 bx+x1-(TILE_BORDER-1)*dx, by+y1-TILE_BORDER*dy,
2239 draw_rect_coords(dr, bx+x1, by+y1,
2240 bx+x1-(TILE_BORDER-1)*dx, by+y1-(TILE_BORDER-1)*dy,
2245 static void draw_barrier(drawing *dr, game_drawstate *ds,
2246 int x, int y, int dir, int phase)
2248 int bx = WINDOW_OFFSET + TILE_SIZE * x;
2249 int by = WINDOW_OFFSET + TILE_SIZE * y;
2252 x1 = (X(dir) > 0 ? TILE_SIZE : X(dir) == 0 ? TILE_BORDER : 0);
2253 y1 = (Y(dir) > 0 ? TILE_SIZE : Y(dir) == 0 ? TILE_BORDER : 0);
2254 w = (X(dir) ? TILE_BORDER : TILE_SIZE - TILE_BORDER);
2255 h = (Y(dir) ? TILE_BORDER : TILE_SIZE - TILE_BORDER);
2258 draw_rect(dr, bx+x1-X(dir), by+y1-Y(dir), w, h, COL_WIRE);
2260 draw_rect(dr, bx+x1, by+y1, w, h, COL_BARRIER);
2265 * draw_tile() is passed physical coordinates
2267 static void draw_tile(drawing *dr, game_state *state, game_drawstate *ds,
2268 int x, int y, int tile, int src, float angle, int cursor)
2270 int bx = WINDOW_OFFSET + TILE_SIZE * x;
2271 int by = WINDOW_OFFSET + TILE_SIZE * y;
2273 float cx, cy, ex, ey, tx, ty;
2274 int dir, col, phase;
2277 * When we draw a single tile, we must draw everything up to
2278 * and including the borders around the tile. This means that
2279 * if the neighbouring tiles have connections to those borders,
2280 * we must draw those connections on the borders themselves.
2283 clip(dr, bx, by, TILE_SIZE+TILE_BORDER, TILE_SIZE+TILE_BORDER);
2286 * So. First blank the tile out completely: draw a big
2287 * rectangle in border colour, and a smaller rectangle in
2288 * background colour to fill it in.
2290 draw_rect(dr, bx, by, TILE_SIZE+TILE_BORDER, TILE_SIZE+TILE_BORDER,
2292 draw_rect(dr, bx+TILE_BORDER, by+TILE_BORDER,
2293 TILE_SIZE-TILE_BORDER, TILE_SIZE-TILE_BORDER,
2294 tile & LOCKED ? COL_LOCKED : COL_BACKGROUND);
2297 * Draw an inset outline rectangle as a cursor, in whichever of
2298 * COL_LOCKED and COL_BACKGROUND we aren't currently drawing
2302 draw_line(dr, bx+TILE_SIZE/8, by+TILE_SIZE/8,
2303 bx+TILE_SIZE/8, by+TILE_SIZE-TILE_SIZE/8,
2304 tile & LOCKED ? COL_BACKGROUND : COL_LOCKED);
2305 draw_line(dr, bx+TILE_SIZE/8, by+TILE_SIZE/8,
2306 bx+TILE_SIZE-TILE_SIZE/8, by+TILE_SIZE/8,
2307 tile & LOCKED ? COL_BACKGROUND : COL_LOCKED);
2308 draw_line(dr, bx+TILE_SIZE-TILE_SIZE/8, by+TILE_SIZE/8,
2309 bx+TILE_SIZE-TILE_SIZE/8, by+TILE_SIZE-TILE_SIZE/8,
2310 tile & LOCKED ? COL_BACKGROUND : COL_LOCKED);
2311 draw_line(dr, bx+TILE_SIZE/8, by+TILE_SIZE-TILE_SIZE/8,
2312 bx+TILE_SIZE-TILE_SIZE/8, by+TILE_SIZE-TILE_SIZE/8,
2313 tile & LOCKED ? COL_BACKGROUND : COL_LOCKED);
2317 * Set up the rotation matrix.
2319 matrix[0] = (float)cos(angle * PI / 180.0);
2320 matrix[1] = (float)-sin(angle * PI / 180.0);
2321 matrix[2] = (float)sin(angle * PI / 180.0);
2322 matrix[3] = (float)cos(angle * PI / 180.0);
2327 cx = cy = TILE_BORDER + (TILE_SIZE-TILE_BORDER) / 2.0F - 0.5F;
2328 col = (tile & ACTIVE ? COL_POWERED : COL_WIRE);
2329 for (dir = 1; dir < 0x10; dir <<= 1) {
2331 ex = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * X(dir);
2332 ey = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * Y(dir);
2333 MATMUL(tx, ty, matrix, ex, ey);
2334 draw_thick_line(dr, bx+(int)cx, by+(int)cy,
2335 bx+(int)(cx+tx), by+(int)(cy+ty),
2339 for (dir = 1; dir < 0x10; dir <<= 1) {
2341 ex = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * X(dir);
2342 ey = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * Y(dir);
2343 MATMUL(tx, ty, matrix, ex, ey);
2344 draw_line(dr, bx+(int)cx, by+(int)cy,
2345 bx+(int)(cx+tx), by+(int)(cy+ty), col);
2350 * Draw the box in the middle. We do this in blue if the tile
2351 * is an unpowered endpoint, in cyan if the tile is a powered
2352 * endpoint, in black if the tile is the centrepiece, and
2353 * otherwise not at all.
2358 else if (COUNT(tile) == 1) {
2359 col = (tile & ACTIVE ? COL_POWERED : COL_ENDPOINT);
2364 points[0] = +1; points[1] = +1;
2365 points[2] = +1; points[3] = -1;
2366 points[4] = -1; points[5] = -1;
2367 points[6] = -1; points[7] = +1;
2369 for (i = 0; i < 8; i += 2) {
2370 ex = (TILE_SIZE * 0.24F) * points[i];
2371 ey = (TILE_SIZE * 0.24F) * points[i+1];
2372 MATMUL(tx, ty, matrix, ex, ey);
2373 points[i] = bx+(int)(cx+tx);
2374 points[i+1] = by+(int)(cy+ty);
2377 draw_polygon(dr, points, 4, col, COL_WIRE);
2381 * Draw the points on the border if other tiles are connected
2384 for (dir = 1; dir < 0x10; dir <<= 1) {
2385 int dx, dy, px, py, lx, ly, vx, vy, ox, oy;
2393 if (ox < 0 || ox >= state->width || oy < 0 || oy >= state->height)
2396 if (!(tile(state, GX(ox), GY(oy)) & F(dir)))
2399 px = bx + (int)(dx>0 ? TILE_SIZE + TILE_BORDER - 1 : dx<0 ? 0 : cx);
2400 py = by + (int)(dy>0 ? TILE_SIZE + TILE_BORDER - 1 : dy<0 ? 0 : cy);
2401 lx = dx * (TILE_BORDER-1);
2402 ly = dy * (TILE_BORDER-1);
2406 if (angle == 0.0 && (tile & dir)) {
2408 * If we are fully connected to the other tile, we must
2409 * draw right across the tile border. (We can use our
2410 * own ACTIVE state to determine what colour to do this
2411 * in: if we are fully connected to the other tile then
2412 * the two ACTIVE states will be the same.)
2414 draw_rect_coords(dr, px-vx, py-vy, px+lx+vx, py+ly+vy, COL_WIRE);
2415 draw_rect_coords(dr, px, py, px+lx, py+ly,
2416 (tile & ACTIVE) ? COL_POWERED : COL_WIRE);
2419 * The other tile extends into our border, but isn't
2420 * actually connected to us. Just draw a single black
2423 draw_rect_coords(dr, px, py, px, py, COL_WIRE);
2428 * Draw barrier corners, and then barriers.
2430 for (phase = 0; phase < 2; phase++) {
2431 for (dir = 1; dir < 0x10; dir <<= 1) {
2432 int x1, y1, corner = FALSE;
2434 * If at least one barrier terminates at the corner
2435 * between dir and A(dir), draw a barrier corner.
2437 if (barrier(state, GX(x), GY(y)) & (dir | A(dir))) {
2441 * Only count barriers terminating at this corner
2442 * if they're physically next to the corner. (That
2443 * is, if they've wrapped round from the far side
2444 * of the screen, they don't count.)
2448 if (x1 >= 0 && x1 < state->width &&
2449 y1 >= 0 && y1 < state->height &&
2450 (barrier(state, GX(x1), GY(y1)) & A(dir))) {
2455 if (x1 >= 0 && x1 < state->width &&
2456 y1 >= 0 && y1 < state->height &&
2457 (barrier(state, GX(x1), GY(y1)) & dir))
2464 * At least one barrier terminates here. Draw a
2467 draw_barrier_corner(dr, ds, x, y,
2468 X(dir)+X(A(dir)), Y(dir)+Y(A(dir)),
2473 for (dir = 1; dir < 0x10; dir <<= 1)
2474 if (barrier(state, GX(x), GY(y)) & dir)
2475 draw_barrier(dr, ds, x, y, dir, phase);
2480 draw_update(dr, bx, by, TILE_SIZE+TILE_BORDER, TILE_SIZE+TILE_BORDER);
2483 static void game_redraw(drawing *dr, game_drawstate *ds, game_state *oldstate,
2484 game_state *state, int dir, game_ui *ui, float t, float ft)
2486 int x, y, tx, ty, frame, last_rotate_dir, moved_origin = FALSE;
2487 unsigned char *active;
2491 * Clear the screen, and draw the exterior barrier lines, if
2492 * this is our first call or if the origin has changed.
2494 if (!ds->started || ui->org_x != ds->org_x || ui->org_y != ds->org_y) {
2500 WINDOW_OFFSET * 2 + TILE_SIZE * state->width + TILE_BORDER,
2501 WINDOW_OFFSET * 2 + TILE_SIZE * state->height + TILE_BORDER,
2504 ds->org_x = ui->org_x;
2505 ds->org_y = ui->org_y;
2506 moved_origin = TRUE;
2508 draw_update(dr, 0, 0,
2509 WINDOW_OFFSET*2 + TILE_SIZE*state->width + TILE_BORDER,
2510 WINDOW_OFFSET*2 + TILE_SIZE*state->height + TILE_BORDER);
2512 for (phase = 0; phase < 2; phase++) {
2514 for (x = 0; x < ds->width; x++) {
2515 if (x+1 < ds->width) {
2516 if (barrier(state, GX(x), GY(0)) & R)
2517 draw_barrier_corner(dr, ds, x, -1, +1, +1, phase);
2518 if (barrier(state, GX(x), GY(ds->height-1)) & R)
2519 draw_barrier_corner(dr, ds, x, ds->height, +1, -1, phase);
2521 if (barrier(state, GX(x), GY(0)) & U) {
2522 draw_barrier_corner(dr, ds, x, -1, -1, +1, phase);
2523 draw_barrier_corner(dr, ds, x, -1, +1, +1, phase);
2524 draw_barrier(dr, ds, x, -1, D, phase);
2526 if (barrier(state, GX(x), GY(ds->height-1)) & D) {
2527 draw_barrier_corner(dr, ds, x, ds->height, -1, -1, phase);
2528 draw_barrier_corner(dr, ds, x, ds->height, +1, -1, phase);
2529 draw_barrier(dr, ds, x, ds->height, U, phase);
2533 for (y = 0; y < ds->height; y++) {
2534 if (y+1 < ds->height) {
2535 if (barrier(state, GX(0), GY(y)) & D)
2536 draw_barrier_corner(dr, ds, -1, y, +1, +1, phase);
2537 if (barrier(state, GX(ds->width-1), GY(y)) & D)
2538 draw_barrier_corner(dr, ds, ds->width, y, -1, +1, phase);
2540 if (barrier(state, GX(0), GY(y)) & L) {
2541 draw_barrier_corner(dr, ds, -1, y, +1, -1, phase);
2542 draw_barrier_corner(dr, ds, -1, y, +1, +1, phase);
2543 draw_barrier(dr, ds, -1, y, R, phase);
2545 if (barrier(state, GX(ds->width-1), GY(y)) & R) {
2546 draw_barrier_corner(dr, ds, ds->width, y, -1, -1, phase);
2547 draw_barrier_corner(dr, ds, ds->width, y, -1, +1, phase);
2548 draw_barrier(dr, ds, ds->width, y, L, phase);
2555 last_rotate_dir = dir==-1 ? oldstate->last_rotate_dir :
2556 state->last_rotate_dir;
2557 if (oldstate && (t < ROTATE_TIME) && last_rotate_dir) {
2559 * We're animating a single tile rotation. Find the turning
2562 tx = (dir==-1 ? oldstate->last_rotate_x : state->last_rotate_x);
2563 ty = (dir==-1 ? oldstate->last_rotate_y : state->last_rotate_y);
2564 angle = last_rotate_dir * dir * 90.0F * (t / ROTATE_TIME);
2571 * We're animating a completion flash. Find which frame
2574 frame = (int)(ft / FLASH_FRAME);
2578 * Draw any tile which differs from the way it was last drawn.
2580 active = compute_active(state, ui->cx, ui->cy);
2582 for (x = 0; x < ds->width; x++)
2583 for (y = 0; y < ds->height; y++) {
2584 unsigned char c = tile(state, GX(x), GY(y)) |
2585 index(state, active, GX(x), GY(y));
2586 int is_src = GX(x) == ui->cx && GY(y) == ui->cy;
2587 int is_anim = GX(x) == tx && GY(y) == ty;
2588 int is_cursor = ui->cur_visible &&
2589 GX(x) == ui->cur_x && GY(y) == ui->cur_y;
2592 * In a completion flash, we adjust the LOCKED bit
2593 * depending on our distance from the centre point and
2597 int rcx = RX(ui->cx), rcy = RY(ui->cy);
2598 int xdist, ydist, dist;
2599 xdist = (x < rcx ? rcx - x : x - rcx);
2600 ydist = (y < rcy ? rcy - y : y - rcy);
2601 dist = (xdist > ydist ? xdist : ydist);
2603 if (frame >= dist && frame < dist+4) {
2604 int lock = (frame - dist) & 1;
2605 lock = lock ? LOCKED : 0;
2606 c = (c &~ LOCKED) | lock;
2611 index(state, ds->visible, x, y) != c ||
2612 index(state, ds->visible, x, y) == 0xFF ||
2613 is_src || is_anim || is_cursor) {
2614 draw_tile(dr, state, ds, x, y, c,
2615 is_src, (is_anim ? angle : 0.0F), is_cursor);
2616 if (is_src || is_anim || is_cursor)
2617 index(state, ds->visible, x, y) = 0xFF;
2619 index(state, ds->visible, x, y) = c;
2624 * Update the status bar.
2627 char statusbuf[256];
2630 n = state->width * state->height;
2631 for (i = a = n2 = 0; i < n; i++) {
2634 if (state->tiles[i] & 0xF)
2638 sprintf(statusbuf, "%sActive: %d/%d",
2639 (state->used_solve ? "Auto-solved. " :
2640 state->completed ? "COMPLETED! " : ""), a, n2);
2642 status_bar(dr, statusbuf);
2648 static float game_anim_length(game_state *oldstate,
2649 game_state *newstate, int dir, game_ui *ui)
2651 int last_rotate_dir;
2654 * Don't animate if last_rotate_dir is zero.
2656 last_rotate_dir = dir==-1 ? oldstate->last_rotate_dir :
2657 newstate->last_rotate_dir;
2658 if (last_rotate_dir)
2664 static float game_flash_length(game_state *oldstate,
2665 game_state *newstate, int dir, game_ui *ui)
2668 * If the game has just been completed, we display a completion
2671 if (!oldstate->completed && newstate->completed &&
2672 !oldstate->used_solve && !newstate->used_solve) {
2674 if (size < newstate->width)
2675 size = newstate->width;
2676 if (size < newstate->height)
2677 size = newstate->height;
2678 return FLASH_FRAME * (size+4);
2684 static int game_timing_state(game_state *state, game_ui *ui)
2689 static void game_print_size(game_params *params, float *x, float *y)
2694 * I'll use 8mm squares by default.
2696 game_compute_size(params, 800, &pw, &ph);
2701 static void draw_diagram(drawing *dr, game_drawstate *ds, int x, int y,
2702 int topleft, int v, int drawlines, int ink)
2704 int tx, ty, cx, cy, r, br, k, thick;
2706 tx = WINDOW_OFFSET + TILE_SIZE * x;
2707 ty = WINDOW_OFFSET + TILE_SIZE * y;
2710 * Find our centre point.
2713 cx = tx + (v & L ? TILE_SIZE / 4 : TILE_SIZE / 6);
2714 cy = ty + (v & U ? TILE_SIZE / 4 : TILE_SIZE / 6);
2716 br = TILE_SIZE / 32;
2718 cx = tx + TILE_SIZE / 2;
2719 cy = ty + TILE_SIZE / 2;
2726 * Draw the square block if we have an endpoint.
2728 if (v == 1 || v == 2 || v == 4 || v == 8)
2729 draw_rect(dr, cx - br, cy - br, br*2, br*2, ink);
2732 * Draw each radial line.
2735 for (k = 1; k < 16; k *= 2)
2737 int x1 = min(cx, cx + (r-thick) * X(k));
2738 int x2 = max(cx, cx + (r-thick) * X(k));
2739 int y1 = min(cy, cy + (r-thick) * Y(k));
2740 int y2 = max(cy, cy + (r-thick) * Y(k));
2741 draw_rect(dr, x1 - thick, y1 - thick,
2742 (x2 - x1) + 2*thick, (y2 - y1) + 2*thick, ink);
2747 static void game_print(drawing *dr, game_state *state, int tilesize)
2749 int w = state->width, h = state->height;
2750 int ink = print_mono_colour(dr, 0);
2753 /* Ick: fake up `ds->tilesize' for macro expansion purposes */
2754 game_drawstate ads, *ds = &ads;
2755 game_set_size(dr, ds, NULL, tilesize);
2760 print_line_width(dr, TILE_SIZE / (state->wrapping ? 128 : 12));
2761 draw_rect_outline(dr, WINDOW_OFFSET, WINDOW_OFFSET,
2762 TILE_SIZE * w, TILE_SIZE * h, ink);
2767 print_line_width(dr, TILE_SIZE / 128);
2768 for (x = 1; x < w; x++)
2769 draw_line(dr, WINDOW_OFFSET + TILE_SIZE * x, WINDOW_OFFSET,
2770 WINDOW_OFFSET + TILE_SIZE * x, WINDOW_OFFSET + TILE_SIZE * h,
2772 for (y = 1; y < h; y++)
2773 draw_line(dr, WINDOW_OFFSET, WINDOW_OFFSET + TILE_SIZE * y,
2774 WINDOW_OFFSET + TILE_SIZE * w, WINDOW_OFFSET + TILE_SIZE * y,
2780 for (y = 0; y <= h; y++)
2781 for (x = 0; x <= w; x++) {
2782 int b = barrier(state, x % w, y % h);
2783 if (x < w && (b & U))
2784 draw_rect(dr, WINDOW_OFFSET + TILE_SIZE * x - TILE_SIZE/24,
2785 WINDOW_OFFSET + TILE_SIZE * y - TILE_SIZE/24,
2786 TILE_SIZE + TILE_SIZE/24 * 2, TILE_SIZE/24 * 2, ink);
2787 if (y < h && (b & L))
2788 draw_rect(dr, WINDOW_OFFSET + TILE_SIZE * x - TILE_SIZE/24,
2789 WINDOW_OFFSET + TILE_SIZE * y - TILE_SIZE/24,
2790 TILE_SIZE/24 * 2, TILE_SIZE + TILE_SIZE/24 * 2, ink);
2796 for (y = 0; y < h; y++)
2797 for (x = 0; x < w; x++) {
2798 int vx, v = tile(state, x, y);
2799 int locked = v & LOCKED;
2804 * Rotate into a standard orientation for the top left
2808 while (vx != 0 && vx != 15 && vx != 1 && vx != 9 && vx != 13 &&
2813 * Draw the top left corner diagram.
2815 draw_diagram(dr, ds, x, y, TRUE, vx, TRUE, ink);
2818 * Draw the real solution diagram, if we're doing so.
2820 draw_diagram(dr, ds, x, y, FALSE, v, locked, ink);
2828 const struct game thegame = {
2836 TRUE, game_configure, custom_params,
2844 FALSE, game_text_format,
2852 PREFERRED_TILE_SIZE, game_compute_size, game_set_size,
2855 game_free_drawstate,
2859 TRUE, FALSE, game_print_size, game_print,
2860 TRUE, /* wants_statusbar */
2861 FALSE, game_timing_state,