2 * sixteen.c: `16-puzzle', a sliding-tiles jigsaw which differs
3 * from the 15-puzzle in that you toroidally rotate a row or column
17 #define BORDER TILE_SIZE /* big border to fill with arrows */
18 #define HIGHLIGHT_WIDTH (TILE_SIZE / 20)
19 #define COORD(x) ( (x) * TILE_SIZE + BORDER )
20 #define FROMCOORD(x) ( ((x) - BORDER + 2*TILE_SIZE) / TILE_SIZE - 2 )
22 #define ANIM_TIME 0.13F
23 #define FLASH_FRAME 0.13F
25 #define X(state, i) ( (i) % (state)->w )
26 #define Y(state, i) ( (i) / (state)->w )
27 #define C(state, x, y) ( (y) * (state)->w + (x) )
46 int just_used_solve; /* used to suppress undo animation */
47 int used_solve; /* used to suppress completion flash */
48 int movecount, movetarget;
49 int last_movement_sense;
52 static game_params *default_params(void)
54 game_params *ret = snew(game_params);
62 static int game_fetch_preset(int i, char **name, game_params **params)
69 case 0: w = 3, h = 3; break;
70 case 1: w = 4, h = 3; break;
71 case 2: w = 4, h = 4; break;
72 case 3: w = 5, h = 4; break;
73 case 4: w = 5, h = 5; break;
74 default: return FALSE;
77 sprintf(buf, "%dx%d", w, h);
79 *params = ret = snew(game_params);
86 static void free_params(game_params *params)
91 static game_params *dup_params(game_params *params)
93 game_params *ret = snew(game_params);
94 *ret = *params; /* structure copy */
98 static game_params *decode_params(char const *string)
100 game_params *ret = default_params();
102 ret->w = ret->h = atoi(string);
103 while (*string && isdigit(*string)) string++;
104 if (*string == 'x') {
106 ret->h = atoi(string);
107 while (*string && isdigit((unsigned char)*string))
110 if (*string == 'm') {
112 ret->movetarget = atoi(string);
113 while (*string && isdigit((unsigned char)*string))
120 static char *encode_params(game_params *params)
124 sprintf(data, "%dx%d", params->w, params->h);
129 static config_item *game_configure(game_params *params)
134 ret = snewn(4, config_item);
136 ret[0].name = "Width";
137 ret[0].type = C_STRING;
138 sprintf(buf, "%d", params->w);
139 ret[0].sval = dupstr(buf);
142 ret[1].name = "Height";
143 ret[1].type = C_STRING;
144 sprintf(buf, "%d", params->h);
145 ret[1].sval = dupstr(buf);
148 ret[2].name = "Number of shuffling moves";
149 ret[2].type = C_STRING;
150 sprintf(buf, "%d", params->movetarget);
151 ret[2].sval = dupstr(buf);
162 static game_params *custom_params(config_item *cfg)
164 game_params *ret = snew(game_params);
166 ret->w = atoi(cfg[0].sval);
167 ret->h = atoi(cfg[1].sval);
168 ret->movetarget = atoi(cfg[2].sval);
173 static char *validate_params(game_params *params)
175 if (params->w < 2 && params->h < 2)
176 return "Width and height must both be at least two";
181 static int perm_parity(int *perm, int n)
187 for (i = 0; i < n-1; i++)
188 for (j = i+1; j < n; j++)
189 if (perm[i] > perm[j])
195 static char *new_game_seed(game_params *params, random_state *rs,
204 n = params->w * params->h;
206 tiles = snewn(n, int);
208 if (params->movetarget) {
209 int prevstart = -1, prevoffset = -1, prevdirection = 0, nrepeats = 0;
212 * Shuffle the old-fashioned way, by making a series of
213 * single moves on the grid.
216 for (i = 0; i < n; i++)
219 for (i = 0; i < params->movetarget; i++) {
220 int start, offset, len, direction;
224 * Choose a move to make. We can choose from any row
228 j = random_upto(rs, params->w + params->h);
237 start = (j - params->w) * params->w;
242 direction = -1 + 2 * random_upto(rs, 2);
245 * To at least _try_ to avoid boring cases, check that
246 * this move doesn't directly undo the previous one, or
247 * repeat it so many times as to turn it into fewer
250 if (start == prevstart && offset == prevoffset) {
251 if (direction == -prevdirection)
252 continue; /* inverse of previous move */
253 else if (2 * (nrepeats+1) > len)
254 continue; /* previous move repeated too often */
257 /* If we didn't `continue', we've found an OK move to make. */
262 * Now save the move into the `prev' variables.
264 if (start == prevstart && offset == prevoffset) {
269 prevdirection = direction;
277 start += (len-1) * offset;
281 for (j = 0; j+1 < len; j++)
282 tiles[start + j*offset] = tiles[start + (j+1)*offset];
283 tiles[start + (len-1) * offset] = tmp;
288 used = snewn(n, int);
290 for (i = 0; i < n; i++) {
296 * If both dimensions are odd, there is a parity
299 if (params->w & params->h & 1)
305 * Place everything except (possibly) the last two tiles.
307 for (x = 0, i = n; i > stop; i--) {
308 int k = i > 1 ? random_upto(rs, i) : 0;
311 for (j = 0; j < n; j++)
312 if (!used[j] && (k-- == 0))
315 assert(j < n && !used[j]);
318 while (tiles[x] >= 0)
326 * Find the last two locations, and the last two
329 while (tiles[x] >= 0)
334 while (tiles[x] >= 0)
339 for (i = 0; i < n; i++)
343 for (i = p1+1; i < n; i++)
349 * Try the last two tiles one way round. If that fails,
354 if (perm_parity(tiles, n) != 0) {
357 assert(perm_parity(tiles, n) == 0);
365 * Now construct the game seed, by describing the tile array as
366 * a simple sequence of comma-separated integers.
370 for (i = 0; i < n; i++) {
374 k = sprintf(buf, "%d,", tiles[i]+1);
376 ret = sresize(ret, retlen + k + 1, char);
377 strcpy(ret + retlen, buf);
380 ret[retlen-1] = '\0'; /* delete last comma */
387 static void game_free_aux_info(game_aux_info *aux)
389 assert(!"Shouldn't happen");
393 static char *validate_seed(game_params *params, char *seed)
399 area = params->w * params->h;
403 used = snewn(area, int);
404 for (i = 0; i < area; i++)
407 for (i = 0; i < area; i++) {
411 if (*p < '0' || *p > '9') {
412 err = "Not enough numbers in string";
415 while (*p >= '0' && *p <= '9')
417 if (i < area-1 && *p != ',') {
418 err = "Expected comma after number";
421 else if (i == area-1 && *p) {
422 err = "Excess junk at end of string";
426 if (n < 1 || n > area) {
427 err = "Number out of range";
431 err = "Number used twice";
436 if (*p) p++; /* eat comma */
444 static game_state *new_game(game_params *params, char *seed)
446 game_state *state = snew(game_state);
450 state->w = params->w;
451 state->h = params->h;
452 state->n = params->w * params->h;
453 state->tiles = snewn(state->n, int);
457 for (i = 0; i < state->n; i++) {
459 state->tiles[i] = atoi(p);
460 while (*p && *p != ',')
462 if (*p) p++; /* eat comma */
466 state->completed = state->movecount = 0;
467 state->movetarget = params->movetarget;
468 state->used_solve = state->just_used_solve = FALSE;
469 state->last_movement_sense = 0;
474 static game_state *dup_game(game_state *state)
476 game_state *ret = snew(game_state);
481 ret->tiles = snewn(state->w * state->h, int);
482 memcpy(ret->tiles, state->tiles, state->w * state->h * sizeof(int));
483 ret->completed = state->completed;
484 ret->movecount = state->movecount;
485 ret->movetarget = state->movetarget;
486 ret->used_solve = state->used_solve;
487 ret->just_used_solve = state->just_used_solve;
488 ret->last_movement_sense = state->last_movement_sense;
493 static void free_game(game_state *state)
498 static game_state *solve_game(game_state *state, game_aux_info *aux,
501 game_state *ret = dup_game(state);
505 * Simply replace the grid with a solved one. For this game,
506 * this isn't a useful operation for actually telling the user
507 * what they should have done, but it is useful for
508 * conveniently being able to get hold of a clean state from
509 * which to practise manoeuvres.
511 for (i = 0; i < ret->n; i++)
513 ret->used_solve = ret->just_used_solve = TRUE;
514 ret->completed = ret->movecount = 1;
519 static char *game_text_format(game_state *state)
521 char *ret, *p, buf[80];
522 int x, y, col, maxlen;
525 * First work out how many characters we need to display each
528 col = sprintf(buf, "%d", state->n);
531 * Now we know the exact total size of the grid we're going to
532 * produce: it's got h rows, each containing w lots of col, w-1
533 * spaces and a trailing newline.
535 maxlen = state->h * state->w * (col+1);
537 ret = snewn(maxlen+1, char);
540 for (y = 0; y < state->h; y++) {
541 for (x = 0; x < state->w; x++) {
542 int v = state->tiles[state->w*y+x];
543 sprintf(buf, "%*d", col, v);
553 assert(p - ret == maxlen);
558 static game_ui *new_ui(game_state *state)
563 static void free_ui(game_ui *ui)
567 static game_state *make_move(game_state *from, game_ui *ui,
568 int x, int y, int button)
571 int dx, dy, tx, ty, n;
574 if (button != LEFT_BUTTON && button != RIGHT_BUTTON)
579 if (cx == -1 && cy >= 0 && cy < from->h)
580 n = from->w, dx = +1, dy = 0;
581 else if (cx == from->w && cy >= 0 && cy < from->h)
582 n = from->w, dx = -1, dy = 0;
583 else if (cy == -1 && cx >= 0 && cx < from->w)
584 n = from->h, dy = +1, dx = 0;
585 else if (cy == from->h && cx >= 0 && cx < from->w)
586 n = from->h, dy = -1, dx = 0;
588 return NULL; /* invalid click location */
590 /* reverse direction if right hand button is pressed */
591 if (button == RIGHT_BUTTON)
593 dx = -dx; if (dx) cx = from->w - 1 - cx;
594 dy = -dy; if (dy) cy = from->h - 1 - cy;
597 ret = dup_game(from);
598 ret->just_used_solve = FALSE; /* zero this in a hurry */
603 tx = (cx + dx + from->w) % from->w;
604 ty = (cy + dy + from->h) % from->h;
605 ret->tiles[C(ret, cx, cy)] = from->tiles[C(from, tx, ty)];
610 ret->last_movement_sense = -(dx+dy);
613 * See if the game has been completed.
615 if (!ret->completed) {
616 ret->completed = ret->movecount;
617 for (n = 0; n < ret->n; n++)
618 if (ret->tiles[n] != n+1)
619 ret->completed = FALSE;
625 /* ----------------------------------------------------------------------
629 struct game_drawstate {
635 static void game_size(game_params *params, int *x, int *y)
637 *x = TILE_SIZE * params->w + 2 * BORDER;
638 *y = TILE_SIZE * params->h + 2 * BORDER;
641 static float *game_colours(frontend *fe, game_state *state, int *ncolours)
643 float *ret = snewn(3 * NCOLOURS, float);
647 frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
650 * Drop the background colour so that the highlight is
651 * noticeably brighter than it while still being under 1.
653 max = ret[COL_BACKGROUND*3];
654 for (i = 1; i < 3; i++)
655 if (ret[COL_BACKGROUND*3+i] > max)
656 max = ret[COL_BACKGROUND*3+i];
657 if (max * 1.2F > 1.0F) {
658 for (i = 0; i < 3; i++)
659 ret[COL_BACKGROUND*3+i] /= (max * 1.2F);
662 for (i = 0; i < 3; i++) {
663 ret[COL_HIGHLIGHT * 3 + i] = ret[COL_BACKGROUND * 3 + i] * 1.2F;
664 ret[COL_LOWLIGHT * 3 + i] = ret[COL_BACKGROUND * 3 + i] * 0.8F;
665 ret[COL_TEXT * 3 + i] = 0.0;
668 *ncolours = NCOLOURS;
672 static game_drawstate *game_new_drawstate(game_state *state)
674 struct game_drawstate *ds = snew(struct game_drawstate);
680 ds->bgcolour = COL_BACKGROUND;
681 ds->tiles = snewn(ds->w*ds->h, int);
682 for (i = 0; i < ds->w*ds->h; i++)
688 static void game_free_drawstate(game_drawstate *ds)
694 static void draw_tile(frontend *fe, game_state *state, int x, int y,
695 int tile, int flash_colour)
698 draw_rect(fe, x, y, TILE_SIZE, TILE_SIZE,
704 coords[0] = x + TILE_SIZE - 1;
705 coords[1] = y + TILE_SIZE - 1;
706 coords[2] = x + TILE_SIZE - 1;
709 coords[5] = y + TILE_SIZE - 1;
710 draw_polygon(fe, coords, 3, TRUE, COL_LOWLIGHT);
711 draw_polygon(fe, coords, 3, FALSE, COL_LOWLIGHT);
715 draw_polygon(fe, coords, 3, TRUE, COL_HIGHLIGHT);
716 draw_polygon(fe, coords, 3, FALSE, COL_HIGHLIGHT);
718 draw_rect(fe, x + HIGHLIGHT_WIDTH, y + HIGHLIGHT_WIDTH,
719 TILE_SIZE - 2*HIGHLIGHT_WIDTH, TILE_SIZE - 2*HIGHLIGHT_WIDTH,
722 sprintf(str, "%d", tile);
723 draw_text(fe, x + TILE_SIZE/2, y + TILE_SIZE/2,
724 FONT_VARIABLE, TILE_SIZE/3, ALIGN_VCENTRE | ALIGN_HCENTRE,
727 draw_update(fe, x, y, TILE_SIZE, TILE_SIZE);
730 static void draw_arrow(frontend *fe, int x, int y, int xdx, int xdy)
733 int ydy = -xdx, ydx = xdy;
735 #define POINT(n, xx, yy) ( \
736 coords[2*(n)+0] = x + (xx)*xdx + (yy)*ydx, \
737 coords[2*(n)+1] = y + (xx)*xdy + (yy)*ydy)
739 POINT(0, TILE_SIZE / 2, 3 * TILE_SIZE / 4); /* top of arrow */
740 POINT(1, 3 * TILE_SIZE / 4, TILE_SIZE / 2); /* right corner */
741 POINT(2, 5 * TILE_SIZE / 8, TILE_SIZE / 2); /* right concave */
742 POINT(3, 5 * TILE_SIZE / 8, TILE_SIZE / 4); /* bottom right */
743 POINT(4, 3 * TILE_SIZE / 8, TILE_SIZE / 4); /* bottom left */
744 POINT(5, 3 * TILE_SIZE / 8, TILE_SIZE / 2); /* left concave */
745 POINT(6, TILE_SIZE / 4, TILE_SIZE / 2); /* left corner */
747 draw_polygon(fe, coords, 7, TRUE, COL_LOWLIGHT);
748 draw_polygon(fe, coords, 7, FALSE, COL_TEXT);
751 static void game_redraw(frontend *fe, game_drawstate *ds, game_state *oldstate,
752 game_state *state, int dir, game_ui *ui,
753 float animtime, float flashtime)
758 int frame = (int)(flashtime / FLASH_FRAME);
759 bgcolour = (frame % 2 ? COL_LOWLIGHT : COL_HIGHLIGHT);
761 bgcolour = COL_BACKGROUND;
767 TILE_SIZE * state->w + 2 * BORDER,
768 TILE_SIZE * state->h + 2 * BORDER, COL_BACKGROUND);
769 draw_update(fe, 0, 0,
770 TILE_SIZE * state->w + 2 * BORDER,
771 TILE_SIZE * state->h + 2 * BORDER);
774 * Recessed area containing the whole puzzle.
776 coords[0] = COORD(state->w) + HIGHLIGHT_WIDTH - 1;
777 coords[1] = COORD(state->h) + HIGHLIGHT_WIDTH - 1;
778 coords[2] = COORD(state->w) + HIGHLIGHT_WIDTH - 1;
779 coords[3] = COORD(0) - HIGHLIGHT_WIDTH;
780 coords[4] = COORD(0) - HIGHLIGHT_WIDTH;
781 coords[5] = COORD(state->h) + HIGHLIGHT_WIDTH - 1;
782 draw_polygon(fe, coords, 3, TRUE, COL_HIGHLIGHT);
783 draw_polygon(fe, coords, 3, FALSE, COL_HIGHLIGHT);
785 coords[1] = COORD(0) - HIGHLIGHT_WIDTH;
786 coords[0] = COORD(0) - HIGHLIGHT_WIDTH;
787 draw_polygon(fe, coords, 3, TRUE, COL_LOWLIGHT);
788 draw_polygon(fe, coords, 3, FALSE, COL_LOWLIGHT);
791 * Arrows for making moves.
793 for (i = 0; i < state->w; i++) {
794 draw_arrow(fe, COORD(i), COORD(0), +1, 0);
795 draw_arrow(fe, COORD(i+1), COORD(state->h), -1, 0);
797 for (i = 0; i < state->h; i++) {
798 draw_arrow(fe, COORD(state->w), COORD(i), 0, +1);
799 draw_arrow(fe, COORD(0), COORD(i+1), 0, -1);
806 * Now draw each tile.
809 clip(fe, COORD(0), COORD(0), TILE_SIZE*state->w, TILE_SIZE*state->h);
811 for (i = 0; i < state->n; i++) {
814 * Figure out what should be displayed at this
815 * location. It's either a simple tile, or it's a
816 * transition between two tiles (in which case we say
817 * -1 because it must always be drawn).
820 if (oldstate && oldstate->tiles[i] != state->tiles[i])
827 if (ds->bgcolour != bgcolour || /* always redraw when flashing */
828 ds->tiles[i] != t || ds->tiles[i] == -1 || t == -1) {
832 * Figure out what to _actually_ draw, and where to
836 int x0, y0, x1, y1, dx, dy;
843 sense = -oldstate->last_movement_sense;
845 sense = state->last_movement_sense;
851 * FIXME: must be prepared to draw a double
852 * tile in some situations.
856 * Find the coordinates of this tile in the old and
859 x1 = COORD(X(state, i));
860 y1 = COORD(Y(state, i));
861 for (j = 0; j < oldstate->n; j++)
862 if (oldstate->tiles[j] == state->tiles[i])
864 assert(j < oldstate->n);
865 x0 = COORD(X(state, j));
866 y0 = COORD(Y(state, j));
870 dx != TILE_SIZE * sense) {
871 dx = (dx < 0 ? dx + TILE_SIZE * state->w :
872 dx - TILE_SIZE * state->w);
873 assert(abs(dx) == TILE_SIZE);
877 dy != TILE_SIZE * sense) {
878 dy = (dy < 0 ? dy + TILE_SIZE * state->h :
879 dy - TILE_SIZE * state->h);
880 assert(abs(dy) == TILE_SIZE);
883 c = (animtime / ANIM_TIME);
884 if (c < 0.0F) c = 0.0F;
885 if (c > 1.0F) c = 1.0F;
887 x = x0 + (int)(c * dx);
888 y = y0 + (int)(c * dy);
889 x2 = x1 - dx + (int)(c * dx);
890 y2 = y1 - dy + (int)(c * dy);
892 x = COORD(X(state, i));
893 y = COORD(Y(state, i));
897 draw_tile(fe, state, x, y, t, bgcolour);
898 if (x2 != -1 || y2 != -1)
899 draw_tile(fe, state, x2, y2, t, bgcolour);
906 ds->bgcolour = bgcolour;
909 * Update the status bar.
915 * Don't show the new status until we're also showing the
916 * new _state_ - after the game animation is complete.
921 if (state->used_solve)
922 sprintf(statusbuf, "Moves since auto-solve: %d",
923 state->movecount - state->completed);
925 sprintf(statusbuf, "%sMoves: %d",
926 (state->completed ? "COMPLETED! " : ""),
927 (state->completed ? state->completed : state->movecount));
928 if (state->movetarget)
929 sprintf(statusbuf+strlen(statusbuf), " (target %d)",
933 status_bar(fe, statusbuf);
937 static float game_anim_length(game_state *oldstate,
938 game_state *newstate, int dir)
940 if ((dir > 0 && newstate->just_used_solve) ||
941 (dir < 0 && oldstate->just_used_solve))
947 static float game_flash_length(game_state *oldstate,
948 game_state *newstate, int dir)
950 if (!oldstate->completed && newstate->completed &&
951 !oldstate->used_solve && !newstate->used_solve)
952 return 2 * FLASH_FRAME;
957 static int game_wants_statusbar(void)
963 #define thegame sixteen
966 const struct game thegame = {
967 "Sixteen", "games.sixteen",
974 TRUE, game_configure, custom_params,
983 TRUE, game_text_format,
994 game_wants_statusbar,