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 void decode_params(game_params *ret, char const *string)
100 ret->w = ret->h = atoi(string);
102 while (*string && isdigit(*string)) string++;
103 if (*string == 'x') {
105 ret->h = atoi(string);
106 while (*string && isdigit((unsigned char)*string))
109 if (*string == 'm') {
111 ret->movetarget = atoi(string);
112 while (*string && isdigit((unsigned char)*string))
117 static char *encode_params(game_params *params, int full)
121 sprintf(data, "%dx%d", params->w, params->h);
122 /* Shuffle limit is part of the limited parameters, because we have to
123 * supply the target move count. */
124 if (params->movetarget)
125 sprintf(data + strlen(data), "m%d", params->movetarget);
130 static config_item *game_configure(game_params *params)
135 ret = snewn(4, config_item);
137 ret[0].name = "Width";
138 ret[0].type = C_STRING;
139 sprintf(buf, "%d", params->w);
140 ret[0].sval = dupstr(buf);
143 ret[1].name = "Height";
144 ret[1].type = C_STRING;
145 sprintf(buf, "%d", params->h);
146 ret[1].sval = dupstr(buf);
149 ret[2].name = "Number of shuffling moves";
150 ret[2].type = C_STRING;
151 sprintf(buf, "%d", params->movetarget);
152 ret[2].sval = dupstr(buf);
163 static game_params *custom_params(config_item *cfg)
165 game_params *ret = snew(game_params);
167 ret->w = atoi(cfg[0].sval);
168 ret->h = atoi(cfg[1].sval);
169 ret->movetarget = atoi(cfg[2].sval);
174 static char *validate_params(game_params *params)
176 if (params->w < 2 && params->h < 2)
177 return "Width and height must both be at least two";
182 static int perm_parity(int *perm, int n)
188 for (i = 0; i < n-1; i++)
189 for (j = i+1; j < n; j++)
190 if (perm[i] > perm[j])
196 static char *new_game_desc(game_params *params, random_state *rs,
197 game_aux_info **aux, int interactive)
205 n = params->w * params->h;
207 tiles = snewn(n, int);
209 if (params->movetarget) {
211 int max = (params->w > params->h ? params->w : params->h);
212 int *prevmoves = snewn(max, int);
215 * Shuffle the old-fashioned way, by making a series of
216 * single moves on the grid.
219 for (i = 0; i < n; i++)
222 for (i = 0; i < params->movetarget; i++) {
223 int start, offset, len, direction, index;
227 * Choose a move to make. We can choose from any row
231 j = random_upto(rs, params->w + params->h);
241 index = j - params->w;
242 start = index * params->w;
247 direction = -1 + 2 * random_upto(rs, 2);
250 * To at least _try_ to avoid boring cases, check
251 * that this move doesn't directly undo a previous
252 * one, or repeat it so many times as to turn it
253 * into fewer moves in the opposite direction. (For
254 * example, in a row of length 4, we're allowed to
255 * move it the same way twice, but not three
258 * We track this for each individual row/column,
259 * and clear all the counters as soon as a
260 * perpendicular move is made. This isn't perfect
261 * (it _can't_ guaranteeably be perfect - there
262 * will always come a move count beyond which a
263 * shorter solution will be possible than the one
264 * which constructed the position) but it should
265 * sort out all the obvious cases.
267 if (offset == prevoffset) {
268 tmp = prevmoves[index] + direction;
269 if (abs(2*tmp) > len || abs(tmp) < abs(prevmoves[index]))
273 /* If we didn't `continue', we've found an OK move to make. */
274 if (offset != prevoffset) {
276 for (i = 0; i < max; i++)
280 prevmoves[index] += direction;
288 start += (len-1) * offset;
292 for (j = 0; j+1 < len; j++)
293 tiles[start + j*offset] = tiles[start + (j+1)*offset];
294 tiles[start + (len-1) * offset] = tmp;
301 used = snewn(n, int);
303 for (i = 0; i < n; i++) {
309 * If both dimensions are odd, there is a parity
312 if (params->w & params->h & 1)
318 * Place everything except (possibly) the last two tiles.
320 for (x = 0, i = n; i > stop; i--) {
321 int k = i > 1 ? random_upto(rs, i) : 0;
324 for (j = 0; j < n; j++)
325 if (!used[j] && (k-- == 0))
328 assert(j < n && !used[j]);
331 while (tiles[x] >= 0)
339 * Find the last two locations, and the last two
342 while (tiles[x] >= 0)
347 while (tiles[x] >= 0)
352 for (i = 0; i < n; i++)
356 for (i = p1+1; i < n; i++)
362 * Try the last two tiles one way round. If that fails,
367 if (perm_parity(tiles, n) != 0) {
370 assert(perm_parity(tiles, n) == 0);
378 * Now construct the game description, by describing the tile
379 * array as a simple sequence of comma-separated integers.
383 for (i = 0; i < n; i++) {
387 k = sprintf(buf, "%d,", tiles[i]+1);
389 ret = sresize(ret, retlen + k + 1, char);
390 strcpy(ret + retlen, buf);
393 ret[retlen-1] = '\0'; /* delete last comma */
400 static void game_free_aux_info(game_aux_info *aux)
402 assert(!"Shouldn't happen");
406 static char *validate_desc(game_params *params, char *desc)
412 area = params->w * params->h;
416 used = snewn(area, int);
417 for (i = 0; i < area; i++)
420 for (i = 0; i < area; i++) {
424 if (*p < '0' || *p > '9') {
425 err = "Not enough numbers in string";
428 while (*p >= '0' && *p <= '9')
430 if (i < area-1 && *p != ',') {
431 err = "Expected comma after number";
434 else if (i == area-1 && *p) {
435 err = "Excess junk at end of string";
439 if (n < 1 || n > area) {
440 err = "Number out of range";
444 err = "Number used twice";
449 if (*p) p++; /* eat comma */
457 static game_state *new_game(midend_data *me, game_params *params, char *desc)
459 game_state *state = snew(game_state);
463 state->w = params->w;
464 state->h = params->h;
465 state->n = params->w * params->h;
466 state->tiles = snewn(state->n, int);
470 for (i = 0; i < state->n; i++) {
472 state->tiles[i] = atoi(p);
473 while (*p && *p != ',')
475 if (*p) p++; /* eat comma */
479 state->completed = state->movecount = 0;
480 state->movetarget = params->movetarget;
481 state->used_solve = state->just_used_solve = FALSE;
482 state->last_movement_sense = 0;
487 static game_state *dup_game(game_state *state)
489 game_state *ret = snew(game_state);
494 ret->tiles = snewn(state->w * state->h, int);
495 memcpy(ret->tiles, state->tiles, state->w * state->h * sizeof(int));
496 ret->completed = state->completed;
497 ret->movecount = state->movecount;
498 ret->movetarget = state->movetarget;
499 ret->used_solve = state->used_solve;
500 ret->just_used_solve = state->just_used_solve;
501 ret->last_movement_sense = state->last_movement_sense;
506 static void free_game(game_state *state)
511 static game_state *solve_game(game_state *state, game_aux_info *aux,
514 game_state *ret = dup_game(state);
518 * Simply replace the grid with a solved one. For this game,
519 * this isn't a useful operation for actually telling the user
520 * what they should have done, but it is useful for
521 * conveniently being able to get hold of a clean state from
522 * which to practise manoeuvres.
524 for (i = 0; i < ret->n; i++)
526 ret->used_solve = ret->just_used_solve = TRUE;
527 ret->completed = ret->movecount = 1;
532 static char *game_text_format(game_state *state)
534 char *ret, *p, buf[80];
535 int x, y, col, maxlen;
538 * First work out how many characters we need to display each
541 col = sprintf(buf, "%d", state->n);
544 * Now we know the exact total size of the grid we're going to
545 * produce: it's got h rows, each containing w lots of col, w-1
546 * spaces and a trailing newline.
548 maxlen = state->h * state->w * (col+1);
550 ret = snewn(maxlen+1, char);
553 for (y = 0; y < state->h; y++) {
554 for (x = 0; x < state->w; x++) {
555 int v = state->tiles[state->w*y+x];
556 sprintf(buf, "%*d", col, v);
566 assert(p - ret == maxlen);
571 static game_ui *new_ui(game_state *state)
576 static void free_ui(game_ui *ui)
580 static game_state *make_move(game_state *from, game_ui *ui, game_drawstate *ds,
581 int x, int y, int button) {
583 int dx, dy, tx, ty, n;
587 if (button != LEFT_BUTTON && button != RIGHT_BUTTON)
592 if (cx == -1 && cy >= 0 && cy < from->h)
593 n = from->w, dx = +1, dy = 0;
594 else if (cx == from->w && cy >= 0 && cy < from->h)
595 n = from->w, dx = -1, dy = 0;
596 else if (cy == -1 && cx >= 0 && cx < from->w)
597 n = from->h, dy = +1, dx = 0;
598 else if (cy == from->h && cx >= 0 && cx < from->w)
599 n = from->h, dy = -1, dx = 0;
601 return NULL; /* invalid click location */
603 /* reverse direction if right hand button is pressed */
604 if (button == RIGHT_BUTTON)
606 dx = -dx; if (dx) cx = from->w - 1 - cx;
607 dy = -dy; if (dy) cy = from->h - 1 - cy;
610 ret = dup_game(from);
611 ret->just_used_solve = FALSE; /* zero this in a hurry */
616 tx = (cx + dx + from->w) % from->w;
617 ty = (cy + dy + from->h) % from->h;
618 ret->tiles[C(ret, cx, cy)] = from->tiles[C(from, tx, ty)];
623 ret->last_movement_sense = -(dx+dy);
626 * See if the game has been completed.
628 if (!ret->completed) {
629 ret->completed = ret->movecount;
630 for (n = 0; n < ret->n; n++)
631 if (ret->tiles[n] != n+1)
632 ret->completed = FALSE;
638 /* ----------------------------------------------------------------------
642 struct game_drawstate {
648 static void game_size(game_params *params, int *x, int *y)
650 *x = TILE_SIZE * params->w + 2 * BORDER;
651 *y = TILE_SIZE * params->h + 2 * BORDER;
654 static float *game_colours(frontend *fe, game_state *state, int *ncolours)
656 float *ret = snewn(3 * NCOLOURS, float);
660 frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
663 * Drop the background colour so that the highlight is
664 * noticeably brighter than it while still being under 1.
666 max = ret[COL_BACKGROUND*3];
667 for (i = 1; i < 3; i++)
668 if (ret[COL_BACKGROUND*3+i] > max)
669 max = ret[COL_BACKGROUND*3+i];
670 if (max * 1.2F > 1.0F) {
671 for (i = 0; i < 3; i++)
672 ret[COL_BACKGROUND*3+i] /= (max * 1.2F);
675 for (i = 0; i < 3; i++) {
676 ret[COL_HIGHLIGHT * 3 + i] = ret[COL_BACKGROUND * 3 + i] * 1.2F;
677 ret[COL_LOWLIGHT * 3 + i] = ret[COL_BACKGROUND * 3 + i] * 0.8F;
678 ret[COL_TEXT * 3 + i] = 0.0;
681 *ncolours = NCOLOURS;
685 static game_drawstate *game_new_drawstate(game_state *state)
687 struct game_drawstate *ds = snew(struct game_drawstate);
693 ds->bgcolour = COL_BACKGROUND;
694 ds->tiles = snewn(ds->w*ds->h, int);
695 for (i = 0; i < ds->w*ds->h; i++)
701 static void game_free_drawstate(game_drawstate *ds)
707 static void draw_tile(frontend *fe, game_state *state, int x, int y,
708 int tile, int flash_colour)
711 draw_rect(fe, x, y, TILE_SIZE, TILE_SIZE,
717 coords[0] = x + TILE_SIZE - 1;
718 coords[1] = y + TILE_SIZE - 1;
719 coords[2] = x + TILE_SIZE - 1;
722 coords[5] = y + TILE_SIZE - 1;
723 draw_polygon(fe, coords, 3, TRUE, COL_LOWLIGHT);
724 draw_polygon(fe, coords, 3, FALSE, COL_LOWLIGHT);
728 draw_polygon(fe, coords, 3, TRUE, COL_HIGHLIGHT);
729 draw_polygon(fe, coords, 3, FALSE, COL_HIGHLIGHT);
731 draw_rect(fe, x + HIGHLIGHT_WIDTH, y + HIGHLIGHT_WIDTH,
732 TILE_SIZE - 2*HIGHLIGHT_WIDTH, TILE_SIZE - 2*HIGHLIGHT_WIDTH,
735 sprintf(str, "%d", tile);
736 draw_text(fe, x + TILE_SIZE/2, y + TILE_SIZE/2,
737 FONT_VARIABLE, TILE_SIZE/3, ALIGN_VCENTRE | ALIGN_HCENTRE,
740 draw_update(fe, x, y, TILE_SIZE, TILE_SIZE);
743 static void draw_arrow(frontend *fe, int x, int y, int xdx, int xdy)
746 int ydy = -xdx, ydx = xdy;
748 #define POINT(n, xx, yy) ( \
749 coords[2*(n)+0] = x + (xx)*xdx + (yy)*ydx, \
750 coords[2*(n)+1] = y + (xx)*xdy + (yy)*ydy)
752 POINT(0, TILE_SIZE / 2, 3 * TILE_SIZE / 4); /* top of arrow */
753 POINT(1, 3 * TILE_SIZE / 4, TILE_SIZE / 2); /* right corner */
754 POINT(2, 5 * TILE_SIZE / 8, TILE_SIZE / 2); /* right concave */
755 POINT(3, 5 * TILE_SIZE / 8, TILE_SIZE / 4); /* bottom right */
756 POINT(4, 3 * TILE_SIZE / 8, TILE_SIZE / 4); /* bottom left */
757 POINT(5, 3 * TILE_SIZE / 8, TILE_SIZE / 2); /* left concave */
758 POINT(6, TILE_SIZE / 4, TILE_SIZE / 2); /* left corner */
760 draw_polygon(fe, coords, 7, TRUE, COL_LOWLIGHT);
761 draw_polygon(fe, coords, 7, FALSE, COL_TEXT);
764 static void game_redraw(frontend *fe, game_drawstate *ds, game_state *oldstate,
765 game_state *state, int dir, game_ui *ui,
766 float animtime, float flashtime)
771 int frame = (int)(flashtime / FLASH_FRAME);
772 bgcolour = (frame % 2 ? COL_LOWLIGHT : COL_HIGHLIGHT);
774 bgcolour = COL_BACKGROUND;
780 TILE_SIZE * state->w + 2 * BORDER,
781 TILE_SIZE * state->h + 2 * BORDER, COL_BACKGROUND);
782 draw_update(fe, 0, 0,
783 TILE_SIZE * state->w + 2 * BORDER,
784 TILE_SIZE * state->h + 2 * BORDER);
787 * Recessed area containing the whole puzzle.
789 coords[0] = COORD(state->w) + HIGHLIGHT_WIDTH - 1;
790 coords[1] = COORD(state->h) + HIGHLIGHT_WIDTH - 1;
791 coords[2] = COORD(state->w) + HIGHLIGHT_WIDTH - 1;
792 coords[3] = COORD(0) - HIGHLIGHT_WIDTH;
793 coords[4] = COORD(0) - HIGHLIGHT_WIDTH;
794 coords[5] = COORD(state->h) + HIGHLIGHT_WIDTH - 1;
795 draw_polygon(fe, coords, 3, TRUE, COL_HIGHLIGHT);
796 draw_polygon(fe, coords, 3, FALSE, COL_HIGHLIGHT);
798 coords[1] = COORD(0) - HIGHLIGHT_WIDTH;
799 coords[0] = COORD(0) - HIGHLIGHT_WIDTH;
800 draw_polygon(fe, coords, 3, TRUE, COL_LOWLIGHT);
801 draw_polygon(fe, coords, 3, FALSE, COL_LOWLIGHT);
804 * Arrows for making moves.
806 for (i = 0; i < state->w; i++) {
807 draw_arrow(fe, COORD(i), COORD(0), +1, 0);
808 draw_arrow(fe, COORD(i+1), COORD(state->h), -1, 0);
810 for (i = 0; i < state->h; i++) {
811 draw_arrow(fe, COORD(state->w), COORD(i), 0, +1);
812 draw_arrow(fe, COORD(0), COORD(i+1), 0, -1);
819 * Now draw each tile.
822 clip(fe, COORD(0), COORD(0), TILE_SIZE*state->w, TILE_SIZE*state->h);
824 for (i = 0; i < state->n; i++) {
827 * Figure out what should be displayed at this
828 * location. It's either a simple tile, or it's a
829 * transition between two tiles (in which case we say
830 * -1 because it must always be drawn).
833 if (oldstate && oldstate->tiles[i] != state->tiles[i])
840 if (ds->bgcolour != bgcolour || /* always redraw when flashing */
841 ds->tiles[i] != t || ds->tiles[i] == -1 || t == -1) {
845 * Figure out what to _actually_ draw, and where to
849 int x0, y0, x1, y1, dx, dy;
856 sense = -oldstate->last_movement_sense;
858 sense = state->last_movement_sense;
864 * FIXME: must be prepared to draw a double
865 * tile in some situations.
869 * Find the coordinates of this tile in the old and
872 x1 = COORD(X(state, i));
873 y1 = COORD(Y(state, i));
874 for (j = 0; j < oldstate->n; j++)
875 if (oldstate->tiles[j] == state->tiles[i])
877 assert(j < oldstate->n);
878 x0 = COORD(X(state, j));
879 y0 = COORD(Y(state, j));
883 dx != TILE_SIZE * sense) {
884 dx = (dx < 0 ? dx + TILE_SIZE * state->w :
885 dx - TILE_SIZE * state->w);
886 assert(abs(dx) == TILE_SIZE);
890 dy != TILE_SIZE * sense) {
891 dy = (dy < 0 ? dy + TILE_SIZE * state->h :
892 dy - TILE_SIZE * state->h);
893 assert(abs(dy) == TILE_SIZE);
896 c = (animtime / ANIM_TIME);
897 if (c < 0.0F) c = 0.0F;
898 if (c > 1.0F) c = 1.0F;
900 x = x0 + (int)(c * dx);
901 y = y0 + (int)(c * dy);
902 x2 = x1 - dx + (int)(c * dx);
903 y2 = y1 - dy + (int)(c * dy);
905 x = COORD(X(state, i));
906 y = COORD(Y(state, i));
910 draw_tile(fe, state, x, y, t, bgcolour);
911 if (x2 != -1 || y2 != -1)
912 draw_tile(fe, state, x2, y2, t, bgcolour);
919 ds->bgcolour = bgcolour;
922 * Update the status bar.
928 * Don't show the new status until we're also showing the
929 * new _state_ - after the game animation is complete.
934 if (state->used_solve)
935 sprintf(statusbuf, "Moves since auto-solve: %d",
936 state->movecount - state->completed);
938 sprintf(statusbuf, "%sMoves: %d",
939 (state->completed ? "COMPLETED! " : ""),
940 (state->completed ? state->completed : state->movecount));
941 if (state->movetarget)
942 sprintf(statusbuf+strlen(statusbuf), " (target %d)",
946 status_bar(fe, statusbuf);
950 static float game_anim_length(game_state *oldstate,
951 game_state *newstate, int dir, game_ui *ui)
953 if ((dir > 0 && newstate->just_used_solve) ||
954 (dir < 0 && oldstate->just_used_solve))
960 static float game_flash_length(game_state *oldstate,
961 game_state *newstate, int dir, game_ui *ui)
963 if (!oldstate->completed && newstate->completed &&
964 !oldstate->used_solve && !newstate->used_solve)
965 return 2 * FLASH_FRAME;
970 static int game_wants_statusbar(void)
975 static int game_timing_state(game_state *state)
981 #define thegame sixteen
984 const struct game thegame = {
985 "Sixteen", "games.sixteen",
992 TRUE, game_configure, custom_params,
1001 TRUE, game_text_format,
1008 game_free_drawstate,
1012 game_wants_statusbar,
1013 FALSE, game_timing_state,
1014 0, /* mouse_priorities */