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
= snew_dsf(w
* h
);
527 * On a non-wrapping grid, we instantly know that all the edges
528 * round the edge are closed.
531 for (i
= 0; i
< w
; i
++) {
532 edgestate
[i
* 5 + 2] = edgestate
[((h
-1) * w
+ i
) * 5 + 8] = 2;
534 for (i
= 0; i
< h
; i
++) {
535 edgestate
[(i
* w
+ w
-1) * 5 + 1] = edgestate
[(i
* w
) * 5 + 4] = 2;
540 * If we have barriers available, we can mark those edges as
544 for (y
= 0; y
< h
; y
++) for (x
= 0; x
< w
; x
++) {
546 for (d
= 1; d
<= 8; d
+= d
) {
547 if (barriers
[y
*w
+x
] & d
) {
550 * In principle the barrier list should already
551 * contain each barrier from each side, but
552 * let's not take chances with our internal
555 OFFSETWH(x2
, y2
, x
, y
, d
, w
, h
);
556 edgestate
[(y
*w
+x
) * 5 + d
] = 2;
557 edgestate
[(y2
*w
+x2
) * 5 + F(d
)] = 2;
564 * Since most deductions made by this solver are local (the
565 * exception is loop avoidance, where joining two tiles
566 * together on one side of the grid can theoretically permit a
567 * fresh deduction on the other), we can address the scaling
568 * problem inherent in iterating repeatedly over the entire
569 * grid by instead working with a to-do list.
571 todo
= todo_new(w
* h
);
574 * Main deductive loop.
576 done_something
= TRUE
; /* prevent instant termination! */
581 * Take a tile index off the todo list and process it.
583 index
= todo_get(todo
);
586 * If we have run out of immediate things to do, we
587 * have no choice but to scan the whole grid for
588 * longer-range things we've missed. Hence, I now add
589 * every square on the grid back on to the to-do list.
590 * I also set `done_something' to FALSE at this point;
591 * if we later come back here and find it still FALSE,
592 * we will know we've scanned the entire grid without
593 * finding anything new to do, and we can terminate.
597 for (i
= 0; i
< w
*h
; i
++)
599 done_something
= FALSE
;
601 index
= todo_get(todo
);
607 int d
, ourclass
= dsf_canonify(equivalence
, y
*w
+x
);
610 deadendmax
[1] = deadendmax
[2] = deadendmax
[4] = deadendmax
[8] = 0;
612 for (i
= j
= 0; i
< 4 && tilestate
[(y
*w
+x
) * 4 + i
] != 255; i
++) {
614 int nnondeadends
, nondeadends
[4], deadendtotal
;
615 int nequiv
, equiv
[5];
616 int val
= tilestate
[(y
*w
+x
) * 4 + i
];
619 nnondeadends
= deadendtotal
= 0;
622 for (d
= 1; d
<= 8; d
+= d
) {
624 * Immediately rule out this orientation if it
625 * conflicts with any known edge.
627 if ((edgestate
[(y
*w
+x
) * 5 + d
] == 1 && !(val
& d
)) ||
628 (edgestate
[(y
*w
+x
) * 5 + d
] == 2 && (val
& d
)))
633 * Count up the dead-end statistics.
635 if (deadends
[(y
*w
+x
) * 5 + d
] <= area
) {
636 deadendtotal
+= deadends
[(y
*w
+x
) * 5 + d
];
638 nondeadends
[nnondeadends
++] = d
;
642 * Ensure we aren't linking to any tiles,
643 * through edges not already known to be
644 * open, which create a loop.
646 if (edgestate
[(y
*w
+x
) * 5 + d
] == 0) {
649 OFFSETWH(x2
, y2
, x
, y
, d
, w
, h
);
650 c
= dsf_canonify(equivalence
, y2
*w
+x2
);
651 for (k
= 0; k
< nequiv
; k
++)
662 if (nnondeadends
== 0) {
664 * If this orientation links together dead-ends
665 * with a total area of less than the entire
666 * grid, it is invalid.
668 * (We add 1 to deadendtotal because of the
669 * tile itself, of course; one tile linking
670 * dead ends of size 2 and 3 forms a subnetwork
671 * with a total area of 6, not 5.)
673 if (deadendtotal
> 0 && deadendtotal
+1 < area
)
675 } else if (nnondeadends
== 1) {
677 * If this orientation links together one or
678 * more dead-ends with precisely one
679 * non-dead-end, then we may have to mark that
680 * non-dead-end as a dead end going the other
681 * way. However, it depends on whether all
682 * other orientations share the same property.
685 if (deadendmax
[nondeadends
[0]] < deadendtotal
)
686 deadendmax
[nondeadends
[0]] = deadendtotal
;
689 * If this orientation links together two or
690 * more non-dead-ends, then we can rule out the
691 * possibility of putting in new dead-end
692 * markings in those directions.
695 for (k
= 0; k
< nnondeadends
; k
++)
696 deadendmax
[nondeadends
[k
]] = area
+1;
700 tilestate
[(y
*w
+x
) * 4 + j
++] = val
;
701 #ifdef SOLVER_DIAGNOSTICS
703 printf("ruling out orientation %x at %d,%d\n", val
, x
, y
);
707 assert(j
> 0); /* we can't lose _all_ possibilities! */
710 done_something
= TRUE
;
713 * We have ruled out at least one tile orientation.
714 * Make sure the rest are blanked.
717 tilestate
[(y
*w
+x
) * 4 + j
++] = 255;
721 * Now go through the tile orientations again and see
722 * if we've deduced anything new about any edges.
728 for (i
= 0; i
< 4 && tilestate
[(y
*w
+x
) * 4 + i
] != 255; i
++) {
729 a
&= tilestate
[(y
*w
+x
) * 4 + i
];
730 o
|= tilestate
[(y
*w
+x
) * 4 + i
];
732 for (d
= 1; d
<= 8; d
+= d
)
733 if (edgestate
[(y
*w
+x
) * 5 + d
] == 0) {
735 OFFSETWH(x2
, y2
, x
, y
, d
, w
, h
);
738 /* This edge is open in all orientations. */
739 #ifdef SOLVER_DIAGNOSTICS
740 printf("marking edge %d,%d:%d open\n", x
, y
, d
);
742 edgestate
[(y
*w
+x
) * 5 + d
] = 1;
743 edgestate
[(y2
*w
+x2
) * 5 + d2
] = 1;
744 dsf_merge(equivalence
, y
*w
+x
, y2
*w
+x2
);
745 done_something
= TRUE
;
746 todo_add(todo
, y2
*w
+x2
);
747 } else if (!(o
& d
)) {
748 /* This edge is closed in all orientations. */
749 #ifdef SOLVER_DIAGNOSTICS
750 printf("marking edge %d,%d:%d closed\n", x
, y
, d
);
752 edgestate
[(y
*w
+x
) * 5 + d
] = 2;
753 edgestate
[(y2
*w
+x2
) * 5 + d2
] = 2;
754 done_something
= TRUE
;
755 todo_add(todo
, y2
*w
+x2
);
762 * Now check the dead-end markers and see if any of
763 * them has lowered from the real ones.
765 for (d
= 1; d
<= 8; d
+= d
) {
767 OFFSETWH(x2
, y2
, x
, y
, d
, w
, h
);
769 if (deadendmax
[d
] > 0 &&
770 deadends
[(y2
*w
+x2
) * 5 + d2
] > deadendmax
[d
]) {
771 #ifdef SOLVER_DIAGNOSTICS
772 printf("setting dead end value %d,%d:%d to %d\n",
773 x2
, y2
, d2
, deadendmax
[d
]);
775 deadends
[(y2
*w
+x2
) * 5 + d2
] = deadendmax
[d
];
776 done_something
= TRUE
;
777 todo_add(todo
, y2
*w
+x2
);
785 * Mark all completely determined tiles as locked.
788 for (i
= 0; i
< w
*h
; i
++) {
789 if (tilestate
[i
* 4 + 1] == 255) {
790 assert(tilestate
[i
* 4 + 0] != 255);
791 tiles
[i
] = tilestate
[i
* 4] | LOCKED
;
799 * Free up working space.
810 /* ----------------------------------------------------------------------
811 * Randomly select a new game description.
815 * Function to randomly perturb an ambiguous section in a grid, to
816 * attempt to ensure unique solvability.
818 static void perturb(int w
, int h
, unsigned char *tiles
, int wrapping
,
819 random_state
*rs
, int startx
, int starty
, int startd
)
821 struct xyd
*perimeter
, *perim2
, *loop
[2], looppos
[2];
822 int nperim
, perimsize
, nloop
[2], loopsize
[2];
826 * We know that the tile at (startx,starty) is part of an
827 * ambiguous section, and we also know that its neighbour in
828 * direction startd is fully specified. We begin by tracing all
829 * the way round the ambiguous area.
831 nperim
= perimsize
= 0;
836 #ifdef PERTURB_DIAGNOSTICS
837 printf("perturb %d,%d:%d\n", x
, y
, d
);
842 if (nperim
>= perimsize
) {
843 perimsize
= perimsize
* 3 / 2 + 32;
844 perimeter
= sresize(perimeter
, perimsize
, struct xyd
);
846 perimeter
[nperim
].x
= x
;
847 perimeter
[nperim
].y
= y
;
848 perimeter
[nperim
].direction
= d
;
850 #ifdef PERTURB_DIAGNOSTICS
851 printf("perimeter: %d,%d:%d\n", x
, y
, d
);
855 * First, see if we can simply turn left from where we are
856 * and find another locked square.
859 OFFSETWH(x2
, y2
, x
, y
, d2
, w
, h
);
860 if ((!wrapping
&& (abs(x2
-x
) > 1 || abs(y2
-y
) > 1)) ||
861 (tiles
[y2
*w
+x2
] & LOCKED
)) {
865 * Failing that, step left into the new square and look
870 OFFSETWH(x2
, y2
, x
, y
, d
, w
, h
);
871 if ((wrapping
|| (abs(x2
-x
) <= 1 && abs(y2
-y
) <= 1)) &&
872 !(tiles
[y2
*w
+x2
] & LOCKED
)) {
874 * And failing _that_, we're going to have to step
875 * forward into _that_ square and look right at the
876 * same locked square as we started with.
884 } while (x
!= startx
|| y
!= starty
|| d
!= startd
);
887 * Our technique for perturbing this ambiguous area is to
888 * search round its edge for a join we can make: that is, an
889 * edge on the perimeter which is (a) not currently connected,
890 * and (b) connecting it would not yield a full cross on either
891 * side. Then we make that join, search round the network to
892 * find the loop thus constructed, and sever the loop at a
893 * randomly selected other point.
895 perim2
= snewn(nperim
, struct xyd
);
896 memcpy(perim2
, perimeter
, nperim
* sizeof(struct xyd
));
897 /* Shuffle the perimeter, so as to search it without directional bias. */
898 shuffle(perim2
, nperim
, sizeof(*perim2
), rs
);
899 for (i
= 0; i
< nperim
; i
++) {
904 d
= perim2
[i
].direction
;
906 OFFSETWH(x2
, y2
, x
, y
, d
, w
, h
);
907 if (!wrapping
&& (abs(x2
-x
) > 1 || abs(y2
-y
) > 1))
908 continue; /* can't link across non-wrapping border */
909 if (tiles
[y
*w
+x
] & d
)
910 continue; /* already linked in this direction! */
911 if (((tiles
[y
*w
+x
] | d
) & 15) == 15)
912 continue; /* can't turn this tile into a cross */
913 if (((tiles
[y2
*w
+x2
] | F(d
)) & 15) == 15)
914 continue; /* can't turn other tile into a cross */
917 * We've found the point at which we're going to make a new
920 #ifdef PERTURB_DIAGNOSTICS
921 printf("linking %d,%d:%d\n", x
, y
, d
);
924 tiles
[y2
*w
+x2
] |= F(d
);
931 return; /* nothing we can do! */
934 * Now we've constructed a new link, we need to find the entire
935 * loop of which it is a part.
937 * In principle, this involves doing a complete search round
938 * the network. However, I anticipate that in the vast majority
939 * of cases the loop will be quite small, so what I'm going to
940 * do is make _two_ searches round the network in parallel, one
941 * keeping its metaphorical hand on the left-hand wall while
942 * the other keeps its hand on the right. As soon as one of
943 * them gets back to its starting point, I abandon the other.
945 for (i
= 0; i
< 2; i
++) {
946 loopsize
[i
] = nloop
[i
] = 0;
950 looppos
[i
].direction
= d
;
953 for (i
= 0; i
< 2; i
++) {
958 d
= looppos
[i
].direction
;
960 OFFSETWH(x2
, y2
, x
, y
, d
, w
, h
);
963 * Add this path segment to the loop, unless it exactly
964 * reverses the previous one on the loop in which case
965 * we take it away again.
967 #ifdef PERTURB_DIAGNOSTICS
968 printf("looppos[%d] = %d,%d:%d\n", i
, x
, y
, d
);
971 loop
[i
][nloop
[i
]-1].x
== x2
&&
972 loop
[i
][nloop
[i
]-1].y
== y2
&&
973 loop
[i
][nloop
[i
]-1].direction
== F(d
)) {
974 #ifdef PERTURB_DIAGNOSTICS
975 printf("removing path segment %d,%d:%d from loop[%d]\n",
980 if (nloop
[i
] >= loopsize
[i
]) {
981 loopsize
[i
] = loopsize
[i
] * 3 / 2 + 32;
982 loop
[i
] = sresize(loop
[i
], loopsize
[i
], struct xyd
);
984 #ifdef PERTURB_DIAGNOSTICS
985 printf("adding path segment %d,%d:%d to loop[%d]\n",
988 loop
[i
][nloop
[i
]++] = looppos
[i
];
991 #ifdef PERTURB_DIAGNOSTICS
992 printf("tile at new location is %x\n", tiles
[y2
*w
+x2
] & 0xF);
995 for (j
= 0; j
< 4; j
++) {
1000 #ifdef PERTURB_DIAGNOSTICS
1001 printf("trying dir %d\n", d
);
1003 if (tiles
[y2
*w
+x2
] & d
) {
1006 looppos
[i
].direction
= d
;
1012 assert(nloop
[i
] > 0);
1014 if (looppos
[i
].x
== loop
[i
][0].x
&&
1015 looppos
[i
].y
== loop
[i
][0].y
&&
1016 looppos
[i
].direction
== loop
[i
][0].direction
) {
1017 #ifdef PERTURB_DIAGNOSTICS
1018 printf("loop %d finished tracking\n", i
);
1022 * Having found our loop, we now sever it at a
1023 * randomly chosen point - absolutely any will do -
1024 * which is not the one we joined it at to begin
1025 * with. Conveniently, the one we joined it at is
1026 * loop[i][0], so we just avoid that one.
1028 j
= random_upto(rs
, nloop
[i
]-1) + 1;
1031 d
= loop
[i
][j
].direction
;
1032 OFFSETWH(x2
, y2
, x
, y
, d
, w
, h
);
1034 tiles
[y2
*w
+x2
] &= ~F(d
);
1046 * Finally, we must mark the entire disputed section as locked,
1047 * to prevent the perturb function being called on it multiple
1050 * To do this, we _sort_ the perimeter of the area. The
1051 * existing xyd_cmp function will arrange things into columns
1052 * for us, in such a way that each column has the edges in
1053 * vertical order. Then we can work down each column and fill
1054 * in all the squares between an up edge and a down edge.
1056 qsort(perimeter
, nperim
, sizeof(struct xyd
), xyd_cmp
);
1058 for (i
= 0; i
<= nperim
; i
++) {
1059 if (i
== nperim
|| perimeter
[i
].x
> x
) {
1061 * Fill in everything from the last Up edge to the
1062 * bottom of the grid, if necessary.
1066 #ifdef PERTURB_DIAGNOSTICS
1067 printf("resolved: locking tile %d,%d\n", x
, y
);
1069 tiles
[y
* w
+ x
] |= LOCKED
;
1082 if (perimeter
[i
].direction
== U
) {
1085 } else if (perimeter
[i
].direction
== D
) {
1087 * Fill in everything from the last Up edge to here.
1089 assert(x
== perimeter
[i
].x
&& y
<= perimeter
[i
].y
);
1090 while (y
<= perimeter
[i
].y
) {
1091 #ifdef PERTURB_DIAGNOSTICS
1092 printf("resolved: locking tile %d,%d\n", x
, y
);
1094 tiles
[y
* w
+ x
] |= LOCKED
;
1104 static char *new_game_desc(game_params
*params
, random_state
*rs
,
1105 char **aux
, int interactive
)
1107 tree234
*possibilities
, *barriertree
;
1108 int w
, h
, x
, y
, cx
, cy
, nbarriers
;
1109 unsigned char *tiles
, *barriers
;
1118 tiles
= snewn(w
* h
, unsigned char);
1119 barriers
= snewn(w
* h
, unsigned char);
1123 memset(tiles
, 0, w
* h
);
1124 memset(barriers
, 0, w
* h
);
1127 * Construct the unshuffled grid.
1129 * To do this, we simply start at the centre point, repeatedly
1130 * choose a random possibility out of the available ways to
1131 * extend a used square into an unused one, and do it. After
1132 * extending the third line out of a square, we remove the
1133 * fourth from the possibilities list to avoid any full-cross
1134 * squares (which would make the game too easy because they
1135 * only have one orientation).
1137 * The slightly worrying thing is the avoidance of full-cross
1138 * squares. Can this cause our unsophisticated construction
1139 * algorithm to paint itself into a corner, by getting into a
1140 * situation where there are some unreached squares and the
1141 * only way to reach any of them is to extend a T-piece into a
1144 * Answer: no it can't, and here's a proof.
1146 * Any contiguous group of such unreachable squares must be
1147 * surrounded on _all_ sides by T-pieces pointing away from the
1148 * group. (If not, then there is a square which can be extended
1149 * into one of the `unreachable' ones, and so it wasn't
1150 * unreachable after all.) In particular, this implies that
1151 * each contiguous group of unreachable squares must be
1152 * rectangular in shape (any deviation from that yields a
1153 * non-T-piece next to an `unreachable' square).
1155 * So we have a rectangle of unreachable squares, with T-pieces
1156 * forming a solid border around the rectangle. The corners of
1157 * that border must be connected (since every tile connects all
1158 * the lines arriving in it), and therefore the border must
1159 * form a closed loop around the rectangle.
1161 * But this can't have happened in the first place, since we
1162 * _know_ we've avoided creating closed loops! Hence, no such
1163 * situation can ever arise, and the naive grid construction
1164 * algorithm will guaranteeably result in a complete grid
1165 * containing no unreached squares, no full crosses _and_ no
1168 possibilities
= newtree234(xyd_cmp_nc
);
1171 add234(possibilities
, new_xyd(cx
, cy
, R
));
1173 add234(possibilities
, new_xyd(cx
, cy
, U
));
1175 add234(possibilities
, new_xyd(cx
, cy
, L
));
1177 add234(possibilities
, new_xyd(cx
, cy
, D
));
1179 while (count234(possibilities
) > 0) {
1182 int x1
, y1
, d1
, x2
, y2
, d2
, d
;
1185 * Extract a randomly chosen possibility from the list.
1187 i
= random_upto(rs
, count234(possibilities
));
1188 xyd
= delpos234(possibilities
, i
);
1191 d1
= xyd
->direction
;
1194 OFFSET(x2
, y2
, x1
, y1
, d1
, params
);
1196 #ifdef GENERATION_DIAGNOSTICS
1197 printf("picked (%d,%d,%c) <-> (%d,%d,%c)\n",
1198 x1
, y1
, "0RU3L567D9abcdef"[d1
], x2
, y2
, "0RU3L567D9abcdef"[d2
]);
1202 * Make the connection. (We should be moving to an as yet
1205 index(params
, tiles
, x1
, y1
) |= d1
;
1206 assert(index(params
, tiles
, x2
, y2
) == 0);
1207 index(params
, tiles
, x2
, y2
) |= d2
;
1210 * If we have created a T-piece, remove its last
1213 if (COUNT(index(params
, tiles
, x1
, y1
)) == 3) {
1214 struct xyd xyd1
, *xydp
;
1218 xyd1
.direction
= 0x0F ^ index(params
, tiles
, x1
, y1
);
1220 xydp
= find234(possibilities
, &xyd1
, NULL
);
1223 #ifdef GENERATION_DIAGNOSTICS
1224 printf("T-piece; removing (%d,%d,%c)\n",
1225 xydp
->x
, xydp
->y
, "0RU3L567D9abcdef"[xydp
->direction
]);
1227 del234(possibilities
, xydp
);
1233 * Remove all other possibilities that were pointing at the
1234 * tile we've just moved into.
1236 for (d
= 1; d
< 0x10; d
<<= 1) {
1238 struct xyd xyd1
, *xydp
;
1240 OFFSET(x3
, y3
, x2
, y2
, d
, params
);
1245 xyd1
.direction
= d3
;
1247 xydp
= find234(possibilities
, &xyd1
, NULL
);
1250 #ifdef GENERATION_DIAGNOSTICS
1251 printf("Loop avoidance; removing (%d,%d,%c)\n",
1252 xydp
->x
, xydp
->y
, "0RU3L567D9abcdef"[xydp
->direction
]);
1254 del234(possibilities
, xydp
);
1260 * Add new possibilities to the list for moving _out_ of
1261 * the tile we have just moved into.
1263 for (d
= 1; d
< 0x10; d
<<= 1) {
1267 continue; /* we've got this one already */
1269 if (!params
->wrapping
) {
1270 if (d
== U
&& y2
== 0)
1272 if (d
== D
&& y2
== h
-1)
1274 if (d
== L
&& x2
== 0)
1276 if (d
== R
&& x2
== w
-1)
1280 OFFSET(x3
, y3
, x2
, y2
, d
, params
);
1282 if (index(params
, tiles
, x3
, y3
))
1283 continue; /* this would create a loop */
1285 #ifdef GENERATION_DIAGNOSTICS
1286 printf("New frontier; adding (%d,%d,%c)\n",
1287 x2
, y2
, "0RU3L567D9abcdef"[d
]);
1289 add234(possibilities
, new_xyd(x2
, y2
, d
));
1292 /* Having done that, we should have no possibilities remaining. */
1293 assert(count234(possibilities
) == 0);
1294 freetree234(possibilities
);
1296 if (params
->unique
) {
1300 * Run the solver to check unique solubility.
1302 while (!net_solver(w
, h
, tiles
, NULL
, params
->wrapping
)) {
1306 * We expect (in most cases) that most of the grid will
1307 * be uniquely specified already, and the remaining
1308 * ambiguous sections will be small and separate. So
1309 * our strategy is to find each individual such
1310 * section, and perform a perturbation on the network
1313 for (y
= 0; y
< h
; y
++) for (x
= 0; x
< w
; x
++) {
1314 if (x
+1 < w
&& ((tiles
[y
*w
+x
] ^ tiles
[y
*w
+x
+1]) & LOCKED
)) {
1316 if (tiles
[y
*w
+x
] & LOCKED
)
1317 perturb(w
, h
, tiles
, params
->wrapping
, rs
, x
+1, y
, L
);
1319 perturb(w
, h
, tiles
, params
->wrapping
, rs
, x
, y
, R
);
1321 if (y
+1 < h
&& ((tiles
[y
*w
+x
] ^ tiles
[(y
+1)*w
+x
]) & LOCKED
)) {
1323 if (tiles
[y
*w
+x
] & LOCKED
)
1324 perturb(w
, h
, tiles
, params
->wrapping
, rs
, x
, y
+1, U
);
1326 perturb(w
, h
, tiles
, params
->wrapping
, rs
, x
, y
, D
);
1331 * Now n counts the number of ambiguous sections we
1332 * have fiddled with. If we haven't managed to decrease
1333 * it from the last time we ran the solver, give up and
1334 * regenerate the entire grid.
1336 if (prevn
!= -1 && prevn
<= n
)
1337 goto begin_generation
; /* (sorry) */
1343 * The solver will have left a lot of LOCKED bits lying
1344 * around in the tiles array. Remove them.
1346 for (x
= 0; x
< w
*h
; x
++)
1347 tiles
[x
] &= ~LOCKED
;
1351 * Now compute a list of the possible barrier locations.
1353 barriertree
= newtree234(xyd_cmp_nc
);
1354 for (y
= 0; y
< h
; y
++) {
1355 for (x
= 0; x
< w
; x
++) {
1357 if (!(index(params
, tiles
, x
, y
) & R
) &&
1358 (params
->wrapping
|| x
< w
-1))
1359 add234(barriertree
, new_xyd(x
, y
, R
));
1360 if (!(index(params
, tiles
, x
, y
) & D
) &&
1361 (params
->wrapping
|| y
< h
-1))
1362 add234(barriertree
, new_xyd(x
, y
, D
));
1367 * Save the unshuffled grid in aux.
1373 solution
= snewn(w
* h
+ 1, char);
1374 for (i
= 0; i
< w
* h
; i
++)
1375 solution
[i
] = "0123456789abcdef"[tiles
[i
] & 0xF];
1376 solution
[w
*h
] = '\0';
1382 * Now shuffle the grid.
1384 for (y
= 0; y
< h
; y
++) {
1385 for (x
= 0; x
< w
; x
++) {
1386 int orig
= index(params
, tiles
, x
, y
);
1387 int rot
= random_upto(rs
, 4);
1388 index(params
, tiles
, x
, y
) = ROT(orig
, rot
);
1393 * And now choose barrier locations. (We carefully do this
1394 * _after_ shuffling, so that changing the barrier rate in the
1395 * params while keeping the random seed the same will give the
1396 * same shuffled grid and _only_ change the barrier locations.
1397 * Also the way we choose barrier locations, by repeatedly
1398 * choosing one possibility from the list until we have enough,
1399 * is designed to ensure that raising the barrier rate while
1400 * keeping the seed the same will provide a superset of the
1401 * previous barrier set - i.e. if you ask for 10 barriers, and
1402 * then decide that's still too hard and ask for 20, you'll get
1403 * the original 10 plus 10 more, rather than getting 20 new
1404 * ones and the chance of remembering your first 10.)
1406 nbarriers
= (int)(params
->barrier_probability
* count234(barriertree
));
1407 assert(nbarriers
>= 0 && nbarriers
<= count234(barriertree
));
1409 while (nbarriers
> 0) {
1412 int x1
, y1
, d1
, x2
, y2
, d2
;
1415 * Extract a randomly chosen barrier from the list.
1417 i
= random_upto(rs
, count234(barriertree
));
1418 xyd
= delpos234(barriertree
, i
);
1420 assert(xyd
!= NULL
);
1424 d1
= xyd
->direction
;
1427 OFFSET(x2
, y2
, x1
, y1
, d1
, params
);
1430 index(params
, barriers
, x1
, y1
) |= d1
;
1431 index(params
, barriers
, x2
, y2
) |= d2
;
1437 * Clean up the rest of the barrier list.
1442 while ( (xyd
= delpos234(barriertree
, 0)) != NULL
)
1445 freetree234(barriertree
);
1449 * Finally, encode the grid into a string game description.
1451 * My syntax is extremely simple: each square is encoded as a
1452 * hex digit in which bit 0 means a connection on the right,
1453 * bit 1 means up, bit 2 left and bit 3 down. (i.e. the same
1454 * encoding as used internally). Each digit is followed by
1455 * optional barrier indicators: `v' means a vertical barrier to
1456 * the right of it, and `h' means a horizontal barrier below
1459 desc
= snewn(w
* h
* 3 + 1, char);
1461 for (y
= 0; y
< h
; y
++) {
1462 for (x
= 0; x
< w
; x
++) {
1463 *p
++ = "0123456789abcdef"[index(params
, tiles
, x
, y
)];
1464 if ((params
->wrapping
|| x
< w
-1) &&
1465 (index(params
, barriers
, x
, y
) & R
))
1467 if ((params
->wrapping
|| y
< h
-1) &&
1468 (index(params
, barriers
, x
, y
) & D
))
1472 assert(p
- desc
<= w
*h
*3);
1481 static char *validate_desc(game_params
*params
, char *desc
)
1483 int w
= params
->width
, h
= params
->height
;
1486 for (i
= 0; i
< w
*h
; i
++) {
1487 if (*desc
>= '0' && *desc
<= '9')
1489 else if (*desc
>= 'a' && *desc
<= 'f')
1491 else if (*desc
>= 'A' && *desc
<= 'F')
1494 return "Game description shorter than expected";
1496 return "Game description contained unexpected character";
1498 while (*desc
== 'h' || *desc
== 'v')
1502 return "Game description longer than expected";
1507 /* ----------------------------------------------------------------------
1508 * Construct an initial game state, given a description and parameters.
1511 static game_state
*new_game(midend
*me
, game_params
*params
, char *desc
)
1516 assert(params
->width
> 0 && params
->height
> 0);
1517 assert(params
->width
> 1 || params
->height
> 1);
1520 * Create a blank game state.
1522 state
= snew(game_state
);
1523 w
= state
->width
= params
->width
;
1524 h
= state
->height
= params
->height
;
1525 state
->wrapping
= params
->wrapping
;
1526 state
->last_rotate_dir
= state
->last_rotate_x
= state
->last_rotate_y
= 0;
1527 state
->completed
= state
->used_solve
= FALSE
;
1528 state
->tiles
= snewn(state
->width
* state
->height
, unsigned char);
1529 memset(state
->tiles
, 0, state
->width
* state
->height
);
1530 state
->barriers
= snewn(state
->width
* state
->height
, unsigned char);
1531 memset(state
->barriers
, 0, state
->width
* state
->height
);
1534 * Parse the game description into the grid.
1536 for (y
= 0; y
< h
; y
++) {
1537 for (x
= 0; x
< w
; x
++) {
1538 if (*desc
>= '0' && *desc
<= '9')
1539 tile(state
, x
, y
) = *desc
- '0';
1540 else if (*desc
>= 'a' && *desc
<= 'f')
1541 tile(state
, x
, y
) = *desc
- 'a' + 10;
1542 else if (*desc
>= 'A' && *desc
<= 'F')
1543 tile(state
, x
, y
) = *desc
- 'A' + 10;
1546 while (*desc
== 'h' || *desc
== 'v') {
1553 OFFSET(x2
, y2
, x
, y
, d1
, state
);
1556 barrier(state
, x
, y
) |= d1
;
1557 barrier(state
, x2
, y2
) |= d2
;
1565 * Set up border barriers if this is a non-wrapping game.
1567 if (!state
->wrapping
) {
1568 for (x
= 0; x
< state
->width
; x
++) {
1569 barrier(state
, x
, 0) |= U
;
1570 barrier(state
, x
, state
->height
-1) |= D
;
1572 for (y
= 0; y
< state
->height
; y
++) {
1573 barrier(state
, 0, y
) |= L
;
1574 barrier(state
, state
->width
-1, y
) |= R
;
1578 * We check whether this is de-facto a non-wrapping game
1579 * despite the parameters, in case we were passed the
1580 * description of a non-wrapping game. This is so that we
1581 * can change some aspects of the UI behaviour.
1583 state
->wrapping
= FALSE
;
1584 for (x
= 0; x
< state
->width
; x
++)
1585 if (!(barrier(state
, x
, 0) & U
) ||
1586 !(barrier(state
, x
, state
->height
-1) & D
))
1587 state
->wrapping
= TRUE
;
1588 for (y
= 0; y
< state
->width
; y
++)
1589 if (!(barrier(state
, 0, y
) & L
) ||
1590 !(barrier(state
, state
->width
-1, y
) & R
))
1591 state
->wrapping
= TRUE
;
1597 static game_state
*dup_game(game_state
*state
)
1601 ret
= snew(game_state
);
1602 ret
->width
= state
->width
;
1603 ret
->height
= state
->height
;
1604 ret
->wrapping
= state
->wrapping
;
1605 ret
->completed
= state
->completed
;
1606 ret
->used_solve
= state
->used_solve
;
1607 ret
->last_rotate_dir
= state
->last_rotate_dir
;
1608 ret
->last_rotate_x
= state
->last_rotate_x
;
1609 ret
->last_rotate_y
= state
->last_rotate_y
;
1610 ret
->tiles
= snewn(state
->width
* state
->height
, unsigned char);
1611 memcpy(ret
->tiles
, state
->tiles
, state
->width
* state
->height
);
1612 ret
->barriers
= snewn(state
->width
* state
->height
, unsigned char);
1613 memcpy(ret
->barriers
, state
->barriers
, state
->width
* state
->height
);
1618 static void free_game(game_state
*state
)
1620 sfree(state
->tiles
);
1621 sfree(state
->barriers
);
1625 static char *solve_game(game_state
*state
, game_state
*currstate
,
1626 char *aux
, char **error
)
1628 unsigned char *tiles
;
1630 int retlen
, retsize
;
1633 tiles
= snewn(state
->width
* state
->height
, unsigned char);
1637 * Run the internal solver on the provided grid. This might
1638 * not yield a complete solution.
1640 memcpy(tiles
, state
->tiles
, state
->width
* state
->height
);
1641 net_solver(state
->width
, state
->height
, tiles
,
1642 state
->barriers
, state
->wrapping
);
1644 for (i
= 0; i
< state
->width
* state
->height
; i
++) {
1647 if (c
>= '0' && c
<= '9')
1649 else if (c
>= 'a' && c
<= 'f')
1650 tiles
[i
] = c
- 'a' + 10;
1651 else if (c
>= 'A' && c
<= 'F')
1652 tiles
[i
] = c
- 'A' + 10;
1659 * Now construct a string which can be passed to execute_move()
1660 * to transform the current grid into the solved one.
1663 ret
= snewn(retsize
, char);
1665 ret
[retlen
++] = 'S';
1667 for (i
= 0; i
< state
->width
* state
->height
; i
++) {
1668 int from
= currstate
->tiles
[i
], to
= tiles
[i
];
1669 int ft
= from
& (R
|L
|U
|D
), tt
= to
& (R
|L
|U
|D
);
1670 int x
= i
% state
->width
, y
= i
/ state
->width
;
1672 char buf
[80], *p
= buf
;
1675 continue; /* nothing needs doing at all */
1678 * To transform this tile into the desired tile: first
1679 * unlock the tile if it's locked, then rotate it if
1680 * necessary, then lock it if necessary.
1683 p
+= sprintf(p
, ";L%d,%d", x
, y
);
1687 else if (tt
== C(ft
))
1689 else if (tt
== F(ft
))
1696 p
+= sprintf(p
, ";%c%d,%d", chr
, x
, y
);
1699 p
+= sprintf(p
, ";L%d,%d", x
, y
);
1702 if (retlen
+ (p
- buf
) >= retsize
) {
1703 retsize
= retlen
+ (p
- buf
) + 512;
1704 ret
= sresize(ret
, retsize
, char);
1706 memcpy(ret
+retlen
, buf
, p
- buf
);
1711 assert(retlen
< retsize
);
1713 ret
= sresize(ret
, retlen
+1, char);
1720 static char *game_text_format(game_state
*state
)
1725 /* ----------------------------------------------------------------------
1730 * Compute which squares are reachable from the centre square, as a
1731 * quick visual aid to determining how close the game is to
1732 * completion. This is also a simple way to tell if the game _is_
1733 * completed - just call this function and see whether every square
1736 static unsigned char *compute_active(game_state
*state
, int cx
, int cy
)
1738 unsigned char *active
;
1742 active
= snewn(state
->width
* state
->height
, unsigned char);
1743 memset(active
, 0, state
->width
* state
->height
);
1746 * We only store (x,y) pairs in todo, but it's easier to reuse
1747 * xyd_cmp and just store direction 0 every time.
1749 todo
= newtree234(xyd_cmp_nc
);
1750 index(state
, active
, cx
, cy
) = ACTIVE
;
1751 add234(todo
, new_xyd(cx
, cy
, 0));
1753 while ( (xyd
= delpos234(todo
, 0)) != NULL
) {
1754 int x1
, y1
, d1
, x2
, y2
, d2
;
1760 for (d1
= 1; d1
< 0x10; d1
<<= 1) {
1761 OFFSET(x2
, y2
, x1
, y1
, d1
, state
);
1765 * If the next tile in this direction is connected to
1766 * us, and there isn't a barrier in the way, and it
1767 * isn't already marked active, then mark it active and
1768 * add it to the to-examine list.
1770 if ((tile(state
, x1
, y1
) & d1
) &&
1771 (tile(state
, x2
, y2
) & d2
) &&
1772 !(barrier(state
, x1
, y1
) & d1
) &&
1773 !index(state
, active
, x2
, y2
)) {
1774 index(state
, active
, x2
, y2
) = ACTIVE
;
1775 add234(todo
, new_xyd(x2
, y2
, 0));
1779 /* Now we expect the todo list to have shrunk to zero size. */
1780 assert(count234(todo
) == 0);
1787 int org_x
, org_y
; /* origin */
1788 int cx
, cy
; /* source tile (game coordinates) */
1791 random_state
*rs
; /* used for jumbling */
1794 static game_ui
*new_ui(game_state
*state
)
1798 game_ui
*ui
= snew(game_ui
);
1799 ui
->org_x
= ui
->org_y
= 0;
1800 ui
->cur_x
= ui
->cx
= state
->width
/ 2;
1801 ui
->cur_y
= ui
->cy
= state
->height
/ 2;
1802 ui
->cur_visible
= FALSE
;
1803 get_random_seed(&seed
, &seedsize
);
1804 ui
->rs
= random_new(seed
, seedsize
);
1810 static void free_ui(game_ui
*ui
)
1812 random_free(ui
->rs
);
1816 static char *encode_ui(game_ui
*ui
)
1820 * We preserve the origin and centre-point coordinates over a
1823 sprintf(buf
, "O%d,%d;C%d,%d", ui
->org_x
, ui
->org_y
, ui
->cx
, ui
->cy
);
1827 static void decode_ui(game_ui
*ui
, char *encoding
)
1829 sscanf(encoding
, "O%d,%d;C%d,%d",
1830 &ui
->org_x
, &ui
->org_y
, &ui
->cx
, &ui
->cy
);
1833 static void game_changed_state(game_ui
*ui
, game_state
*oldstate
,
1834 game_state
*newstate
)
1838 struct game_drawstate
{
1843 unsigned char *visible
;
1846 /* ----------------------------------------------------------------------
1849 static char *interpret_move(game_state
*state
, game_ui
*ui
,
1850 game_drawstate
*ds
, int x
, int y
, int button
)
1853 int tx
= -1, ty
= -1, dir
= 0;
1854 int shift
= button
& MOD_SHFT
, ctrl
= button
& MOD_CTRL
;
1856 NONE
, ROTATE_LEFT
, ROTATE_180
, ROTATE_RIGHT
, TOGGLE_LOCK
, JUMBLE
,
1857 MOVE_ORIGIN
, MOVE_SOURCE
, MOVE_ORIGIN_AND_SOURCE
, MOVE_CURSOR
1860 button
&= ~MOD_MASK
;
1864 if (button
== LEFT_BUTTON
||
1865 button
== MIDDLE_BUTTON
||
1866 button
== RIGHT_BUTTON
) {
1868 if (ui
->cur_visible
) {
1869 ui
->cur_visible
= FALSE
;
1874 * The button must have been clicked on a valid tile.
1876 x
-= WINDOW_OFFSET
+ TILE_BORDER
;
1877 y
-= WINDOW_OFFSET
+ TILE_BORDER
;
1882 if (tx
>= state
->width
|| ty
>= state
->height
)
1884 /* Transform from physical to game coords */
1885 tx
= (tx
+ ui
->org_x
) % state
->width
;
1886 ty
= (ty
+ ui
->org_y
) % state
->height
;
1887 if (x
% TILE_SIZE
>= TILE_SIZE
- TILE_BORDER
||
1888 y
% TILE_SIZE
>= TILE_SIZE
- TILE_BORDER
)
1891 action
= button
== LEFT_BUTTON ? ROTATE_LEFT
:
1892 button
== RIGHT_BUTTON ? ROTATE_RIGHT
: TOGGLE_LOCK
;
1893 } else if (button
== CURSOR_UP
|| button
== CURSOR_DOWN
||
1894 button
== CURSOR_RIGHT
|| button
== CURSOR_LEFT
) {
1896 case CURSOR_UP
: dir
= U
; break;
1897 case CURSOR_DOWN
: dir
= D
; break;
1898 case CURSOR_LEFT
: dir
= L
; break;
1899 case CURSOR_RIGHT
: dir
= R
; break;
1900 default: return nullret
;
1902 if (shift
&& ctrl
) action
= MOVE_ORIGIN_AND_SOURCE
;
1903 else if (shift
) action
= MOVE_ORIGIN
;
1904 else if (ctrl
) action
= MOVE_SOURCE
;
1905 else action
= MOVE_CURSOR
;
1906 } else if (button
== 'a' || button
== 's' || button
== 'd' ||
1907 button
== 'A' || button
== 'S' || button
== 'D' ||
1908 button
== 'f' || button
== 'F' ||
1909 button
== CURSOR_SELECT
) {
1912 if (button
== 'a' || button
== 'A' || button
== CURSOR_SELECT
)
1913 action
= ROTATE_LEFT
;
1914 else if (button
== 's' || button
== 'S')
1915 action
= TOGGLE_LOCK
;
1916 else if (button
== 'd' || button
== 'D')
1917 action
= ROTATE_RIGHT
;
1918 else if (button
== 'f' || button
== 'F')
1919 action
= ROTATE_180
;
1920 ui
->cur_visible
= TRUE
;
1921 } else if (button
== 'j' || button
== 'J') {
1922 /* XXX should we have some mouse control for this? */
1928 * The middle button locks or unlocks a tile. (A locked tile
1929 * cannot be turned, and is visually marked as being locked.
1930 * This is a convenience for the player, so that once they are
1931 * sure which way round a tile goes, they can lock it and thus
1932 * avoid forgetting later on that they'd already done that one;
1933 * and the locking also prevents them turning the tile by
1934 * accident. If they change their mind, another middle click
1937 if (action
== TOGGLE_LOCK
) {
1939 sprintf(buf
, "L%d,%d", tx
, ty
);
1941 } else if (action
== ROTATE_LEFT
|| action
== ROTATE_RIGHT
||
1942 action
== ROTATE_180
) {
1946 * The left and right buttons have no effect if clicked on a
1949 if (tile(state
, tx
, ty
) & LOCKED
)
1953 * Otherwise, turn the tile one way or the other. Left button
1954 * turns anticlockwise; right button turns clockwise.
1956 sprintf(buf
, "%c%d,%d", (int)(action
== ROTATE_LEFT ?
'A' :
1957 action
== ROTATE_RIGHT ?
'C' : 'F'), tx
, ty
);
1959 } else if (action
== JUMBLE
) {
1961 * Jumble all unlocked tiles to random orientations.
1968 * Maximum string length assumes no int can be converted to
1969 * decimal and take more than 11 digits!
1971 maxlen
= state
->width
* state
->height
* 25 + 3;
1973 ret
= snewn(maxlen
, char);
1977 for (jy
= 0; jy
< state
->height
; jy
++) {
1978 for (jx
= 0; jx
< state
->width
; jx
++) {
1979 if (!(tile(state
, jx
, jy
) & LOCKED
)) {
1980 int rot
= random_upto(ui
->rs
, 4);
1982 p
+= sprintf(p
, ";%c%d,%d", "AFC"[rot
-1], jx
, jy
);
1988 assert(p
- ret
< maxlen
);
1989 ret
= sresize(ret
, p
- ret
, char);
1992 } else if (action
== MOVE_ORIGIN
|| action
== MOVE_SOURCE
||
1993 action
== MOVE_ORIGIN_AND_SOURCE
|| action
== MOVE_CURSOR
) {
1995 if (action
== MOVE_ORIGIN
|| action
== MOVE_ORIGIN_AND_SOURCE
) {
1996 if (state
->wrapping
) {
1997 OFFSET(ui
->org_x
, ui
->org_y
, ui
->org_x
, ui
->org_y
, dir
, state
);
1998 } else return nullret
; /* disallowed for non-wrapping grids */
2000 if (action
== MOVE_SOURCE
|| action
== MOVE_ORIGIN_AND_SOURCE
) {
2001 OFFSET(ui
->cx
, ui
->cy
, ui
->cx
, ui
->cy
, dir
, state
);
2003 if (action
== MOVE_CURSOR
) {
2004 OFFSET(ui
->cur_x
, ui
->cur_y
, ui
->cur_x
, ui
->cur_y
, dir
, state
);
2005 ui
->cur_visible
= TRUE
;
2013 static game_state
*execute_move(game_state
*from
, char *move
)
2016 int tx
, ty
, n
, noanim
, orig
;
2018 ret
= dup_game(from
);
2020 if (move
[0] == 'J' || move
[0] == 'S') {
2022 ret
->used_solve
= TRUE
;
2031 ret
->last_rotate_dir
= 0; /* suppress animation */
2032 ret
->last_rotate_x
= ret
->last_rotate_y
= 0;
2035 if ((move
[0] == 'A' || move
[0] == 'C' ||
2036 move
[0] == 'F' || move
[0] == 'L') &&
2037 sscanf(move
+1, "%d,%d%n", &tx
, &ty
, &n
) >= 2 &&
2038 tx
>= 0 && tx
< from
->width
&& ty
>= 0 && ty
< from
->height
) {
2039 orig
= tile(ret
, tx
, ty
);
2040 if (move
[0] == 'A') {
2041 tile(ret
, tx
, ty
) = A(orig
);
2043 ret
->last_rotate_dir
= +1;
2044 } else if (move
[0] == 'F') {
2045 tile(ret
, tx
, ty
) = F(orig
);
2047 ret
->last_rotate_dir
= +2; /* + for sake of argument */
2048 } else if (move
[0] == 'C') {
2049 tile(ret
, tx
, ty
) = C(orig
);
2051 ret
->last_rotate_dir
= -1;
2053 assert(move
[0] == 'L');
2054 tile(ret
, tx
, ty
) ^= LOCKED
;
2058 if (*move
== ';') move
++;
2065 ret
->last_rotate_x
= tx
;
2066 ret
->last_rotate_y
= ty
;
2070 * Check whether the game has been completed.
2072 * For this purpose it doesn't matter where the source square
2073 * is, because we can start from anywhere and correctly
2074 * determine whether the game is completed.
2077 unsigned char *active
= compute_active(ret
, 0, 0);
2079 int complete
= TRUE
;
2081 for (x1
= 0; x1
< ret
->width
; x1
++)
2082 for (y1
= 0; y1
< ret
->height
; y1
++)
2083 if ((tile(ret
, x1
, y1
) & 0xF) && !index(ret
, active
, x1
, y1
)) {
2085 goto break_label
; /* break out of two loops at once */
2092 ret
->completed
= TRUE
;
2099 /* ----------------------------------------------------------------------
2100 * Routines for drawing the game position on the screen.
2103 static game_drawstate
*game_new_drawstate(drawing
*dr
, game_state
*state
)
2105 game_drawstate
*ds
= snew(game_drawstate
);
2107 ds
->started
= FALSE
;
2108 ds
->width
= state
->width
;
2109 ds
->height
= state
->height
;
2110 ds
->org_x
= ds
->org_y
= -1;
2111 ds
->visible
= snewn(state
->width
* state
->height
, unsigned char);
2112 ds
->tilesize
= 0; /* undecided yet */
2113 memset(ds
->visible
, 0xFF, state
->width
* state
->height
);
2118 static void game_free_drawstate(drawing
*dr
, game_drawstate
*ds
)
2124 static void game_compute_size(game_params
*params
, int tilesize
,
2127 *x
= WINDOW_OFFSET
* 2 + tilesize
* params
->width
+ TILE_BORDER
;
2128 *y
= WINDOW_OFFSET
* 2 + tilesize
* params
->height
+ TILE_BORDER
;
2131 static void game_set_size(drawing
*dr
, game_drawstate
*ds
,
2132 game_params
*params
, int tilesize
)
2134 ds
->tilesize
= tilesize
;
2137 static float *game_colours(frontend
*fe
, int *ncolours
)
2141 ret
= snewn(NCOLOURS
* 3, float);
2142 *ncolours
= NCOLOURS
;
2145 * Basic background colour is whatever the front end thinks is
2146 * a sensible default.
2148 frontend_default_colour(fe
, &ret
[COL_BACKGROUND
* 3]);
2153 ret
[COL_WIRE
* 3 + 0] = 0.0F
;
2154 ret
[COL_WIRE
* 3 + 1] = 0.0F
;
2155 ret
[COL_WIRE
* 3 + 2] = 0.0F
;
2158 * Powered wires and powered endpoints are cyan.
2160 ret
[COL_POWERED
* 3 + 0] = 0.0F
;
2161 ret
[COL_POWERED
* 3 + 1] = 1.0F
;
2162 ret
[COL_POWERED
* 3 + 2] = 1.0F
;
2167 ret
[COL_BARRIER
* 3 + 0] = 1.0F
;
2168 ret
[COL_BARRIER
* 3 + 1] = 0.0F
;
2169 ret
[COL_BARRIER
* 3 + 2] = 0.0F
;
2172 * Unpowered endpoints are blue.
2174 ret
[COL_ENDPOINT
* 3 + 0] = 0.0F
;
2175 ret
[COL_ENDPOINT
* 3 + 1] = 0.0F
;
2176 ret
[COL_ENDPOINT
* 3 + 2] = 1.0F
;
2179 * Tile borders are a darker grey than the background.
2181 ret
[COL_BORDER
* 3 + 0] = 0.5F
* ret
[COL_BACKGROUND
* 3 + 0];
2182 ret
[COL_BORDER
* 3 + 1] = 0.5F
* ret
[COL_BACKGROUND
* 3 + 1];
2183 ret
[COL_BORDER
* 3 + 2] = 0.5F
* ret
[COL_BACKGROUND
* 3 + 2];
2186 * Locked tiles are a grey in between those two.
2188 ret
[COL_LOCKED
* 3 + 0] = 0.75F
* ret
[COL_BACKGROUND
* 3 + 0];
2189 ret
[COL_LOCKED
* 3 + 1] = 0.75F
* ret
[COL_BACKGROUND
* 3 + 1];
2190 ret
[COL_LOCKED
* 3 + 2] = 0.75F
* ret
[COL_BACKGROUND
* 3 + 2];
2195 static void draw_thick_line(drawing
*dr
, int x1
, int y1
, int x2
, int y2
,
2198 draw_line(dr
, x1
-1, y1
, x2
-1, y2
, COL_WIRE
);
2199 draw_line(dr
, x1
+1, y1
, x2
+1, y2
, COL_WIRE
);
2200 draw_line(dr
, x1
, y1
-1, x2
, y2
-1, COL_WIRE
);
2201 draw_line(dr
, x1
, y1
+1, x2
, y2
+1, COL_WIRE
);
2202 draw_line(dr
, x1
, y1
, x2
, y2
, colour
);
2205 static void draw_rect_coords(drawing
*dr
, int x1
, int y1
, int x2
, int y2
,
2208 int mx
= (x1
< x2 ? x1
: x2
);
2209 int my
= (y1
< y2 ? y1
: y2
);
2210 int dx
= (x2
+ x1
- 2*mx
+ 1);
2211 int dy
= (y2
+ y1
- 2*my
+ 1);
2213 draw_rect(dr
, mx
, my
, dx
, dy
, colour
);
2217 * draw_barrier_corner() and draw_barrier() are passed physical coords
2219 static void draw_barrier_corner(drawing
*dr
, game_drawstate
*ds
,
2220 int x
, int y
, int dx
, int dy
, int phase
)
2222 int bx
= WINDOW_OFFSET
+ TILE_SIZE
* x
;
2223 int by
= WINDOW_OFFSET
+ TILE_SIZE
* y
;
2226 x1
= (dx
> 0 ? TILE_SIZE
+TILE_BORDER
-1 : 0);
2227 y1
= (dy
> 0 ? TILE_SIZE
+TILE_BORDER
-1 : 0);
2230 draw_rect_coords(dr
, bx
+x1
+dx
, by
+y1
,
2231 bx
+x1
-TILE_BORDER
*dx
, by
+y1
-(TILE_BORDER
-1)*dy
,
2233 draw_rect_coords(dr
, bx
+x1
, by
+y1
+dy
,
2234 bx
+x1
-(TILE_BORDER
-1)*dx
, by
+y1
-TILE_BORDER
*dy
,
2237 draw_rect_coords(dr
, bx
+x1
, by
+y1
,
2238 bx
+x1
-(TILE_BORDER
-1)*dx
, by
+y1
-(TILE_BORDER
-1)*dy
,
2243 static void draw_barrier(drawing
*dr
, game_drawstate
*ds
,
2244 int x
, int y
, int dir
, int phase
)
2246 int bx
= WINDOW_OFFSET
+ TILE_SIZE
* x
;
2247 int by
= WINDOW_OFFSET
+ TILE_SIZE
* y
;
2250 x1
= (X(dir
) > 0 ? TILE_SIZE
: X(dir
) == 0 ? TILE_BORDER
: 0);
2251 y1
= (Y(dir
) > 0 ? TILE_SIZE
: Y(dir
) == 0 ? TILE_BORDER
: 0);
2252 w
= (X(dir
) ? TILE_BORDER
: TILE_SIZE
- TILE_BORDER
);
2253 h
= (Y(dir
) ? TILE_BORDER
: TILE_SIZE
- TILE_BORDER
);
2256 draw_rect(dr
, bx
+x1
-X(dir
), by
+y1
-Y(dir
), w
, h
, COL_WIRE
);
2258 draw_rect(dr
, bx
+x1
, by
+y1
, w
, h
, COL_BARRIER
);
2263 * draw_tile() is passed physical coordinates
2265 static void draw_tile(drawing
*dr
, game_state
*state
, game_drawstate
*ds
,
2266 int x
, int y
, int tile
, int src
, float angle
, int cursor
)
2268 int bx
= WINDOW_OFFSET
+ TILE_SIZE
* x
;
2269 int by
= WINDOW_OFFSET
+ TILE_SIZE
* y
;
2271 float cx
, cy
, ex
, ey
, tx
, ty
;
2272 int dir
, col
, phase
;
2275 * When we draw a single tile, we must draw everything up to
2276 * and including the borders around the tile. This means that
2277 * if the neighbouring tiles have connections to those borders,
2278 * we must draw those connections on the borders themselves.
2281 clip(dr
, bx
, by
, TILE_SIZE
+TILE_BORDER
, TILE_SIZE
+TILE_BORDER
);
2284 * So. First blank the tile out completely: draw a big
2285 * rectangle in border colour, and a smaller rectangle in
2286 * background colour to fill it in.
2288 draw_rect(dr
, bx
, by
, TILE_SIZE
+TILE_BORDER
, TILE_SIZE
+TILE_BORDER
,
2290 draw_rect(dr
, bx
+TILE_BORDER
, by
+TILE_BORDER
,
2291 TILE_SIZE
-TILE_BORDER
, TILE_SIZE
-TILE_BORDER
,
2292 tile
& LOCKED ? COL_LOCKED
: COL_BACKGROUND
);
2295 * Draw an inset outline rectangle as a cursor, in whichever of
2296 * COL_LOCKED and COL_BACKGROUND we aren't currently drawing
2300 draw_line(dr
, bx
+TILE_SIZE
/8, by
+TILE_SIZE
/8,
2301 bx
+TILE_SIZE
/8, by
+TILE_SIZE
-TILE_SIZE
/8,
2302 tile
& LOCKED ? COL_BACKGROUND
: COL_LOCKED
);
2303 draw_line(dr
, bx
+TILE_SIZE
/8, by
+TILE_SIZE
/8,
2304 bx
+TILE_SIZE
-TILE_SIZE
/8, by
+TILE_SIZE
/8,
2305 tile
& LOCKED ? COL_BACKGROUND
: COL_LOCKED
);
2306 draw_line(dr
, bx
+TILE_SIZE
-TILE_SIZE
/8, by
+TILE_SIZE
/8,
2307 bx
+TILE_SIZE
-TILE_SIZE
/8, by
+TILE_SIZE
-TILE_SIZE
/8,
2308 tile
& LOCKED ? COL_BACKGROUND
: COL_LOCKED
);
2309 draw_line(dr
, bx
+TILE_SIZE
/8, by
+TILE_SIZE
-TILE_SIZE
/8,
2310 bx
+TILE_SIZE
-TILE_SIZE
/8, by
+TILE_SIZE
-TILE_SIZE
/8,
2311 tile
& LOCKED ? COL_BACKGROUND
: COL_LOCKED
);
2315 * Set up the rotation matrix.
2317 matrix
[0] = (float)cos(angle
* PI
/ 180.0);
2318 matrix
[1] = (float)-sin(angle
* PI
/ 180.0);
2319 matrix
[2] = (float)sin(angle
* PI
/ 180.0);
2320 matrix
[3] = (float)cos(angle
* PI
/ 180.0);
2325 cx
= cy
= TILE_BORDER
+ (TILE_SIZE
-TILE_BORDER
) / 2.0F
- 0.5F
;
2326 col
= (tile
& ACTIVE ? COL_POWERED
: COL_WIRE
);
2327 for (dir
= 1; dir
< 0x10; dir
<<= 1) {
2329 ex
= (TILE_SIZE
- TILE_BORDER
- 1.0F
) / 2.0F
* X(dir
);
2330 ey
= (TILE_SIZE
- TILE_BORDER
- 1.0F
) / 2.0F
* Y(dir
);
2331 MATMUL(tx
, ty
, matrix
, ex
, ey
);
2332 draw_thick_line(dr
, bx
+(int)cx
, by
+(int)cy
,
2333 bx
+(int)(cx
+tx
), by
+(int)(cy
+ty
),
2337 for (dir
= 1; dir
< 0x10; dir
<<= 1) {
2339 ex
= (TILE_SIZE
- TILE_BORDER
- 1.0F
) / 2.0F
* X(dir
);
2340 ey
= (TILE_SIZE
- TILE_BORDER
- 1.0F
) / 2.0F
* Y(dir
);
2341 MATMUL(tx
, ty
, matrix
, ex
, ey
);
2342 draw_line(dr
, bx
+(int)cx
, by
+(int)cy
,
2343 bx
+(int)(cx
+tx
), by
+(int)(cy
+ty
), col
);
2348 * Draw the box in the middle. We do this in blue if the tile
2349 * is an unpowered endpoint, in cyan if the tile is a powered
2350 * endpoint, in black if the tile is the centrepiece, and
2351 * otherwise not at all.
2356 else if (COUNT(tile
) == 1) {
2357 col
= (tile
& ACTIVE ? COL_POWERED
: COL_ENDPOINT
);
2362 points
[0] = +1; points
[1] = +1;
2363 points
[2] = +1; points
[3] = -1;
2364 points
[4] = -1; points
[5] = -1;
2365 points
[6] = -1; points
[7] = +1;
2367 for (i
= 0; i
< 8; i
+= 2) {
2368 ex
= (TILE_SIZE
* 0.24F
) * points
[i
];
2369 ey
= (TILE_SIZE
* 0.24F
) * points
[i
+1];
2370 MATMUL(tx
, ty
, matrix
, ex
, ey
);
2371 points
[i
] = bx
+(int)(cx
+tx
);
2372 points
[i
+1] = by
+(int)(cy
+ty
);
2375 draw_polygon(dr
, points
, 4, col
, COL_WIRE
);
2379 * Draw the points on the border if other tiles are connected
2382 for (dir
= 1; dir
< 0x10; dir
<<= 1) {
2383 int dx
, dy
, px
, py
, lx
, ly
, vx
, vy
, ox
, oy
;
2391 if (ox
< 0 || ox
>= state
->width
|| oy
< 0 || oy
>= state
->height
)
2394 if (!(tile(state
, GX(ox
), GY(oy
)) & F(dir
)))
2397 px
= bx
+ (int)(dx
>0 ? TILE_SIZE
+ TILE_BORDER
- 1 : dx
<0 ?
0 : cx
);
2398 py
= by
+ (int)(dy
>0 ? TILE_SIZE
+ TILE_BORDER
- 1 : dy
<0 ?
0 : cy
);
2399 lx
= dx
* (TILE_BORDER
-1);
2400 ly
= dy
* (TILE_BORDER
-1);
2404 if (angle
== 0.0 && (tile
& dir
)) {
2406 * If we are fully connected to the other tile, we must
2407 * draw right across the tile border. (We can use our
2408 * own ACTIVE state to determine what colour to do this
2409 * in: if we are fully connected to the other tile then
2410 * the two ACTIVE states will be the same.)
2412 draw_rect_coords(dr
, px
-vx
, py
-vy
, px
+lx
+vx
, py
+ly
+vy
, COL_WIRE
);
2413 draw_rect_coords(dr
, px
, py
, px
+lx
, py
+ly
,
2414 (tile
& ACTIVE
) ? COL_POWERED
: COL_WIRE
);
2417 * The other tile extends into our border, but isn't
2418 * actually connected to us. Just draw a single black
2421 draw_rect_coords(dr
, px
, py
, px
, py
, COL_WIRE
);
2426 * Draw barrier corners, and then barriers.
2428 for (phase
= 0; phase
< 2; phase
++) {
2429 for (dir
= 1; dir
< 0x10; dir
<<= 1) {
2430 int x1
, y1
, corner
= FALSE
;
2432 * If at least one barrier terminates at the corner
2433 * between dir and A(dir), draw a barrier corner.
2435 if (barrier(state
, GX(x
), GY(y
)) & (dir
| A(dir
))) {
2439 * Only count barriers terminating at this corner
2440 * if they're physically next to the corner. (That
2441 * is, if they've wrapped round from the far side
2442 * of the screen, they don't count.)
2446 if (x1
>= 0 && x1
< state
->width
&&
2447 y1
>= 0 && y1
< state
->height
&&
2448 (barrier(state
, GX(x1
), GY(y1
)) & A(dir
))) {
2453 if (x1
>= 0 && x1
< state
->width
&&
2454 y1
>= 0 && y1
< state
->height
&&
2455 (barrier(state
, GX(x1
), GY(y1
)) & dir
))
2462 * At least one barrier terminates here. Draw a
2465 draw_barrier_corner(dr
, ds
, x
, y
,
2466 X(dir
)+X(A(dir
)), Y(dir
)+Y(A(dir
)),
2471 for (dir
= 1; dir
< 0x10; dir
<<= 1)
2472 if (barrier(state
, GX(x
), GY(y
)) & dir
)
2473 draw_barrier(dr
, ds
, x
, y
, dir
, phase
);
2478 draw_update(dr
, bx
, by
, TILE_SIZE
+TILE_BORDER
, TILE_SIZE
+TILE_BORDER
);
2481 static void game_redraw(drawing
*dr
, game_drawstate
*ds
, game_state
*oldstate
,
2482 game_state
*state
, int dir
, game_ui
*ui
, float t
, float ft
)
2484 int x
, y
, tx
, ty
, frame
, last_rotate_dir
, moved_origin
= FALSE
;
2485 unsigned char *active
;
2489 * Clear the screen, and draw the exterior barrier lines, if
2490 * this is our first call or if the origin has changed.
2492 if (!ds
->started
|| ui
->org_x
!= ds
->org_x
|| ui
->org_y
!= ds
->org_y
) {
2498 WINDOW_OFFSET
* 2 + TILE_SIZE
* state
->width
+ TILE_BORDER
,
2499 WINDOW_OFFSET
* 2 + TILE_SIZE
* state
->height
+ TILE_BORDER
,
2502 ds
->org_x
= ui
->org_x
;
2503 ds
->org_y
= ui
->org_y
;
2504 moved_origin
= TRUE
;
2506 draw_update(dr
, 0, 0,
2507 WINDOW_OFFSET
*2 + TILE_SIZE
*state
->width
+ TILE_BORDER
,
2508 WINDOW_OFFSET
*2 + TILE_SIZE
*state
->height
+ TILE_BORDER
);
2510 for (phase
= 0; phase
< 2; phase
++) {
2512 for (x
= 0; x
< ds
->width
; x
++) {
2513 if (x
+1 < ds
->width
) {
2514 if (barrier(state
, GX(x
), GY(0)) & R
)
2515 draw_barrier_corner(dr
, ds
, x
, -1, +1, +1, phase
);
2516 if (barrier(state
, GX(x
), GY(ds
->height
-1)) & R
)
2517 draw_barrier_corner(dr
, ds
, x
, ds
->height
, +1, -1, phase
);
2519 if (barrier(state
, GX(x
), GY(0)) & U
) {
2520 draw_barrier_corner(dr
, ds
, x
, -1, -1, +1, phase
);
2521 draw_barrier_corner(dr
, ds
, x
, -1, +1, +1, phase
);
2522 draw_barrier(dr
, ds
, x
, -1, D
, phase
);
2524 if (barrier(state
, GX(x
), GY(ds
->height
-1)) & D
) {
2525 draw_barrier_corner(dr
, ds
, x
, ds
->height
, -1, -1, phase
);
2526 draw_barrier_corner(dr
, ds
, x
, ds
->height
, +1, -1, phase
);
2527 draw_barrier(dr
, ds
, x
, ds
->height
, U
, phase
);
2531 for (y
= 0; y
< ds
->height
; y
++) {
2532 if (y
+1 < ds
->height
) {
2533 if (barrier(state
, GX(0), GY(y
)) & D
)
2534 draw_barrier_corner(dr
, ds
, -1, y
, +1, +1, phase
);
2535 if (barrier(state
, GX(ds
->width
-1), GY(y
)) & D
)
2536 draw_barrier_corner(dr
, ds
, ds
->width
, y
, -1, +1, phase
);
2538 if (barrier(state
, GX(0), GY(y
)) & L
) {
2539 draw_barrier_corner(dr
, ds
, -1, y
, +1, -1, phase
);
2540 draw_barrier_corner(dr
, ds
, -1, y
, +1, +1, phase
);
2541 draw_barrier(dr
, ds
, -1, y
, R
, phase
);
2543 if (barrier(state
, GX(ds
->width
-1), GY(y
)) & R
) {
2544 draw_barrier_corner(dr
, ds
, ds
->width
, y
, -1, -1, phase
);
2545 draw_barrier_corner(dr
, ds
, ds
->width
, y
, -1, +1, phase
);
2546 draw_barrier(dr
, ds
, ds
->width
, y
, L
, phase
);
2553 last_rotate_dir
= dir
==-1 ? oldstate
->last_rotate_dir
:
2554 state
->last_rotate_dir
;
2555 if (oldstate
&& (t
< ROTATE_TIME
) && last_rotate_dir
) {
2557 * We're animating a single tile rotation. Find the turning
2560 tx
= (dir
==-1 ? oldstate
->last_rotate_x
: state
->last_rotate_x
);
2561 ty
= (dir
==-1 ? oldstate
->last_rotate_y
: state
->last_rotate_y
);
2562 angle
= last_rotate_dir
* dir
* 90.0F
* (t
/ ROTATE_TIME
);
2569 * We're animating a completion flash. Find which frame
2572 frame
= (int)(ft
/ FLASH_FRAME
);
2576 * Draw any tile which differs from the way it was last drawn.
2578 active
= compute_active(state
, ui
->cx
, ui
->cy
);
2580 for (x
= 0; x
< ds
->width
; x
++)
2581 for (y
= 0; y
< ds
->height
; y
++) {
2582 unsigned char c
= tile(state
, GX(x
), GY(y
)) |
2583 index(state
, active
, GX(x
), GY(y
));
2584 int is_src
= GX(x
) == ui
->cx
&& GY(y
) == ui
->cy
;
2585 int is_anim
= GX(x
) == tx
&& GY(y
) == ty
;
2586 int is_cursor
= ui
->cur_visible
&&
2587 GX(x
) == ui
->cur_x
&& GY(y
) == ui
->cur_y
;
2590 * In a completion flash, we adjust the LOCKED bit
2591 * depending on our distance from the centre point and
2595 int rcx
= RX(ui
->cx
), rcy
= RY(ui
->cy
);
2596 int xdist
, ydist
, dist
;
2597 xdist
= (x
< rcx ? rcx
- x
: x
- rcx
);
2598 ydist
= (y
< rcy ? rcy
- y
: y
- rcy
);
2599 dist
= (xdist
> ydist ? xdist
: ydist
);
2601 if (frame
>= dist
&& frame
< dist
+4) {
2602 int lock
= (frame
- dist
) & 1;
2603 lock
= lock ? LOCKED
: 0;
2604 c
= (c
&~ LOCKED
) | lock
;
2609 index(state
, ds
->visible
, x
, y
) != c
||
2610 index(state
, ds
->visible
, x
, y
) == 0xFF ||
2611 is_src
|| is_anim
|| is_cursor
) {
2612 draw_tile(dr
, state
, ds
, x
, y
, c
,
2613 is_src
, (is_anim ? angle
: 0.0F
), is_cursor
);
2614 if (is_src
|| is_anim
|| is_cursor
)
2615 index(state
, ds
->visible
, x
, y
) = 0xFF;
2617 index(state
, ds
->visible
, x
, y
) = c
;
2622 * Update the status bar.
2625 char statusbuf
[256];
2628 n
= state
->width
* state
->height
;
2629 for (i
= a
= n2
= 0; i
< n
; i
++) {
2632 if (state
->tiles
[i
] & 0xF)
2636 sprintf(statusbuf
, "%sActive: %d/%d",
2637 (state
->used_solve ?
"Auto-solved. " :
2638 state
->completed ?
"COMPLETED! " : ""), a
, n2
);
2640 status_bar(dr
, statusbuf
);
2646 static float game_anim_length(game_state
*oldstate
,
2647 game_state
*newstate
, int dir
, game_ui
*ui
)
2649 int last_rotate_dir
;
2652 * Don't animate if last_rotate_dir is zero.
2654 last_rotate_dir
= dir
==-1 ? oldstate
->last_rotate_dir
:
2655 newstate
->last_rotate_dir
;
2656 if (last_rotate_dir
)
2662 static float game_flash_length(game_state
*oldstate
,
2663 game_state
*newstate
, int dir
, game_ui
*ui
)
2666 * If the game has just been completed, we display a completion
2669 if (!oldstate
->completed
&& newstate
->completed
&&
2670 !oldstate
->used_solve
&& !newstate
->used_solve
) {
2672 if (size
< newstate
->width
)
2673 size
= newstate
->width
;
2674 if (size
< newstate
->height
)
2675 size
= newstate
->height
;
2676 return FLASH_FRAME
* (size
+4);
2682 static int game_timing_state(game_state
*state
, game_ui
*ui
)
2687 static void game_print_size(game_params
*params
, float *x
, float *y
)
2692 * I'll use 8mm squares by default.
2694 game_compute_size(params
, 800, &pw
, &ph
);
2699 static void draw_diagram(drawing
*dr
, game_drawstate
*ds
, int x
, int y
,
2700 int topleft
, int v
, int drawlines
, int ink
)
2702 int tx
, ty
, cx
, cy
, r
, br
, k
, thick
;
2704 tx
= WINDOW_OFFSET
+ TILE_SIZE
* x
;
2705 ty
= WINDOW_OFFSET
+ TILE_SIZE
* y
;
2708 * Find our centre point.
2711 cx
= tx
+ (v
& L ? TILE_SIZE
/ 4 : TILE_SIZE
/ 6);
2712 cy
= ty
+ (v
& U ? TILE_SIZE
/ 4 : TILE_SIZE
/ 6);
2714 br
= TILE_SIZE
/ 32;
2716 cx
= tx
+ TILE_SIZE
/ 2;
2717 cy
= ty
+ TILE_SIZE
/ 2;
2724 * Draw the square block if we have an endpoint.
2726 if (v
== 1 || v
== 2 || v
== 4 || v
== 8)
2727 draw_rect(dr
, cx
- br
, cy
- br
, br
*2, br
*2, ink
);
2730 * Draw each radial line.
2733 for (k
= 1; k
< 16; k
*= 2)
2735 int x1
= min(cx
, cx
+ (r
-thick
) * X(k
));
2736 int x2
= max(cx
, cx
+ (r
-thick
) * X(k
));
2737 int y1
= min(cy
, cy
+ (r
-thick
) * Y(k
));
2738 int y2
= max(cy
, cy
+ (r
-thick
) * Y(k
));
2739 draw_rect(dr
, x1
- thick
, y1
- thick
,
2740 (x2
- x1
) + 2*thick
, (y2
- y1
) + 2*thick
, ink
);
2745 static void game_print(drawing
*dr
, game_state
*state
, int tilesize
)
2747 int w
= state
->width
, h
= state
->height
;
2748 int ink
= print_mono_colour(dr
, 0);
2751 /* Ick: fake up `ds->tilesize' for macro expansion purposes */
2752 game_drawstate ads
, *ds
= &ads
;
2753 game_set_size(dr
, ds
, NULL
, tilesize
);
2758 print_line_width(dr
, TILE_SIZE
/ (state
->wrapping ?
128 : 12));
2759 draw_rect_outline(dr
, WINDOW_OFFSET
, WINDOW_OFFSET
,
2760 TILE_SIZE
* w
, TILE_SIZE
* h
, ink
);
2765 print_line_width(dr
, TILE_SIZE
/ 128);
2766 for (x
= 1; x
< w
; x
++)
2767 draw_line(dr
, WINDOW_OFFSET
+ TILE_SIZE
* x
, WINDOW_OFFSET
,
2768 WINDOW_OFFSET
+ TILE_SIZE
* x
, WINDOW_OFFSET
+ TILE_SIZE
* h
,
2770 for (y
= 1; y
< h
; y
++)
2771 draw_line(dr
, WINDOW_OFFSET
, WINDOW_OFFSET
+ TILE_SIZE
* y
,
2772 WINDOW_OFFSET
+ TILE_SIZE
* w
, WINDOW_OFFSET
+ TILE_SIZE
* y
,
2778 for (y
= 0; y
<= h
; y
++)
2779 for (x
= 0; x
<= w
; x
++) {
2780 int b
= barrier(state
, x
% w
, y
% h
);
2781 if (x
< w
&& (b
& U
))
2782 draw_rect(dr
, WINDOW_OFFSET
+ TILE_SIZE
* x
- TILE_SIZE
/24,
2783 WINDOW_OFFSET
+ TILE_SIZE
* y
- TILE_SIZE
/24,
2784 TILE_SIZE
+ TILE_SIZE
/24 * 2, TILE_SIZE
/24 * 2, ink
);
2785 if (y
< h
&& (b
& L
))
2786 draw_rect(dr
, WINDOW_OFFSET
+ TILE_SIZE
* x
- TILE_SIZE
/24,
2787 WINDOW_OFFSET
+ TILE_SIZE
* y
- TILE_SIZE
/24,
2788 TILE_SIZE
/24 * 2, TILE_SIZE
+ TILE_SIZE
/24 * 2, ink
);
2794 for (y
= 0; y
< h
; y
++)
2795 for (x
= 0; x
< w
; x
++) {
2796 int vx
, v
= tile(state
, x
, y
);
2797 int locked
= v
& LOCKED
;
2802 * Rotate into a standard orientation for the top left
2806 while (vx
!= 0 && vx
!= 15 && vx
!= 1 && vx
!= 9 && vx
!= 13 &&
2811 * Draw the top left corner diagram.
2813 draw_diagram(dr
, ds
, x
, y
, TRUE
, vx
, TRUE
, ink
);
2816 * Draw the real solution diagram, if we're doing so.
2818 draw_diagram(dr
, ds
, x
, y
, FALSE
, v
, locked
, ink
);
2826 const struct game thegame
= {
2827 "Net", "games.net", "net",
2834 TRUE
, game_configure
, custom_params
,
2842 FALSE
, game_text_format
,
2850 PREFERRED_TILE_SIZE
, game_compute_size
, game_set_size
,
2853 game_free_drawstate
,
2857 TRUE
, FALSE
, game_print_size
, game_print
,
2858 TRUE
, /* wants_statusbar */
2859 FALSE
, game_timing_state
,