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
16 #define PREFERRED_TILE_SIZE 48
17 #define TILE_SIZE (ds->tilesize)
18 #define BORDER TILE_SIZE
19 #define HIGHLIGHT_WIDTH (TILE_SIZE / 20)
20 #define COORD(x) ( (x) * TILE_SIZE + BORDER )
21 #define FROMCOORD(x) ( ((x) - BORDER + 2*TILE_SIZE) / TILE_SIZE - 2 )
23 #define ANIM_TIME 0.13F
24 #define FLASH_FRAME 0.13F
26 #define X(state, i) ( (i) % (state)->w )
27 #define Y(state, i) ( (i) / (state)->w )
28 #define C(state, x, y) ( (y) * (state)->w + (x) )
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(const 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((unsigned char)*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(const 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(const 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(const 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(const game_params *params, int full)
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(const game_params *params, random_state *rs,
197 char **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 */
401 static char *validate_desc(const game_params *params, const char *desc)
408 area = params->w * params->h;
412 used = snewn(area, int);
413 for (i = 0; i < area; i++)
416 for (i = 0; i < area; i++) {
420 if (*p < '0' || *p > '9') {
421 err = "Not enough numbers in string";
424 while (*p >= '0' && *p <= '9')
426 if (i < area-1 && *p != ',') {
427 err = "Expected comma after number";
430 else if (i == area-1 && *p) {
431 err = "Excess junk at end of string";
435 if (n < 1 || n > area) {
436 err = "Number out of range";
440 err = "Number used twice";
445 if (*p) p++; /* eat comma */
453 static game_state *new_game(midend *me, const game_params *params,
456 game_state *state = snew(game_state);
460 state->w = params->w;
461 state->h = params->h;
462 state->n = params->w * params->h;
463 state->tiles = snewn(state->n, int);
467 for (i = 0; i < state->n; i++) {
469 state->tiles[i] = atoi(p);
470 while (*p && *p != ',')
472 if (*p) p++; /* eat comma */
476 state->completed = state->movecount = 0;
477 state->movetarget = params->movetarget;
478 state->used_solve = FALSE;
479 state->last_movement_sense = 0;
484 static game_state *dup_game(const game_state *state)
486 game_state *ret = snew(game_state);
491 ret->tiles = snewn(state->w * state->h, int);
492 memcpy(ret->tiles, state->tiles, state->w * state->h * sizeof(int));
493 ret->completed = state->completed;
494 ret->movecount = state->movecount;
495 ret->movetarget = state->movetarget;
496 ret->used_solve = state->used_solve;
497 ret->last_movement_sense = state->last_movement_sense;
502 static void free_game(game_state *state)
508 static char *solve_game(const game_state *state, const game_state *currstate,
509 const char *aux, char **error)
514 static int game_can_format_as_text_now(const game_params *params)
519 static char *game_text_format(const 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);
563 static game_ui *new_ui(const game_state *state)
565 game_ui *ui = snew(game_ui);
568 ui->cur_visible = FALSE;
573 static void free_ui(game_ui *ui)
578 static char *encode_ui(const game_ui *ui)
583 static void decode_ui(game_ui *ui, const char *encoding)
587 static void game_changed_state(game_ui *ui, const game_state *oldstate,
588 const game_state *newstate)
592 struct game_drawstate {
600 static char *interpret_move(const game_state *state, game_ui *ui,
601 const game_drawstate *ds,
602 int x, int y, int button)
604 int cx = -1, cy = -1, dx, dy;
609 if (IS_CURSOR_MOVE(button)) {
610 /* right/down rotates cursor clockwise,
611 * left/up rotates anticlockwise. */
613 cpos = c2pos(state->w, state->h, ui->cur_x, ui->cur_y);
614 diff = c2diff(state->w, state->h, ui->cur_x, ui->cur_y, button);
617 pos2c(state->w, state->h, cpos, &ui->cur_x, &ui->cur_y);
623 if (button == LEFT_BUTTON || button == RIGHT_BUTTON) {
627 } else if (IS_CURSOR_SELECT(button)) {
628 if (ui->cur_visible) {
639 if (cx == -1 && cy >= 0 && cy < state->h)
641 else if (cx == state->w && cy >= 0 && cy < state->h)
643 else if (cy == -1 && cx >= 0 && cx < state->w)
645 else if (cy == state->h && cx >= 0 && cx < state->w)
648 return ""; /* invalid click location */
650 /* reverse direction if right hand button is pressed */
651 if (button == RIGHT_BUTTON || button == CURSOR_SELECT2) {
657 sprintf(buf, "R%d,%d", cy, dx);
659 sprintf(buf, "C%d,%d", cx, dy);
663 static game_state *execute_move(const game_state *from, const char *move)
669 if (!strcmp(move, "S")) {
672 ret = dup_game(from);
675 * Simply replace the grid with a solved one. For this game,
676 * this isn't a useful operation for actually telling the user
677 * what they should have done, but it is useful for
678 * conveniently being able to get hold of a clean state from
679 * which to practise manoeuvres.
681 for (i = 0; i < ret->n; i++)
683 ret->used_solve = TRUE;
684 ret->completed = ret->movecount = 1;
689 if (move[0] == 'R' && sscanf(move+1, "%d,%d", &cy, &dx) == 2 &&
690 cy >= 0 && cy < from->h) {
693 } else if (move[0] == 'C' && sscanf(move+1, "%d,%d", &cx, &dy) == 2 &&
694 cx >= 0 && cx < from->w) {
700 ret = dup_game(from);
703 tx = (cx - dx + from->w) % from->w;
704 ty = (cy - dy + from->h) % from->h;
705 ret->tiles[C(ret, cx, cy)] = from->tiles[C(from, tx, ty)];
712 ret->last_movement_sense = dx+dy;
715 * See if the game has been completed.
717 if (!ret->completed) {
718 ret->completed = ret->movecount;
719 for (n = 0; n < ret->n; n++)
720 if (ret->tiles[n] != n+1)
721 ret->completed = FALSE;
727 /* ----------------------------------------------------------------------
731 static void game_compute_size(const game_params *params, int tilesize,
734 /* Ick: fake up `ds->tilesize' for macro expansion purposes */
735 struct { int tilesize; } ads, *ds = &ads;
736 ads.tilesize = tilesize;
738 *x = TILE_SIZE * params->w + 2 * BORDER;
739 *y = TILE_SIZE * params->h + 2 * BORDER;
742 static void game_set_size(drawing *dr, game_drawstate *ds,
743 const game_params *params, int tilesize)
745 ds->tilesize = tilesize;
748 static float *game_colours(frontend *fe, int *ncolours)
750 float *ret = snewn(3 * NCOLOURS, float);
753 game_mkhighlight(fe, ret, COL_BACKGROUND, COL_HIGHLIGHT, COL_LOWLIGHT);
755 for (i = 0; i < 3; i++)
756 ret[COL_TEXT * 3 + i] = 0.0;
758 *ncolours = NCOLOURS;
762 static game_drawstate *game_new_drawstate(drawing *dr, const game_state *state)
764 struct game_drawstate *ds = snew(struct game_drawstate);
770 ds->bgcolour = COL_BACKGROUND;
771 ds->tiles = snewn(ds->w*ds->h, int);
772 ds->tilesize = 0; /* haven't decided yet */
773 for (i = 0; i < ds->w*ds->h; i++)
775 ds->cur_x = ds->cur_y = -1;
780 static void game_free_drawstate(drawing *dr, game_drawstate *ds)
786 static void draw_tile(drawing *dr, game_drawstate *ds,
787 const game_state *state, int x, int y,
788 int tile, int flash_colour)
791 draw_rect(dr, x, y, TILE_SIZE, TILE_SIZE,
797 coords[0] = x + TILE_SIZE - 1;
798 coords[1] = y + TILE_SIZE - 1;
799 coords[2] = x + TILE_SIZE - 1;
802 coords[5] = y + TILE_SIZE - 1;
803 draw_polygon(dr, coords, 3, COL_LOWLIGHT, COL_LOWLIGHT);
807 draw_polygon(dr, coords, 3, COL_HIGHLIGHT, COL_HIGHLIGHT);
809 draw_rect(dr, x + HIGHLIGHT_WIDTH, y + HIGHLIGHT_WIDTH,
810 TILE_SIZE - 2*HIGHLIGHT_WIDTH, TILE_SIZE - 2*HIGHLIGHT_WIDTH,
813 sprintf(str, "%d", tile);
814 draw_text(dr, x + TILE_SIZE/2, y + TILE_SIZE/2,
815 FONT_VARIABLE, TILE_SIZE/3, ALIGN_VCENTRE | ALIGN_HCENTRE,
818 draw_update(dr, x, y, TILE_SIZE, TILE_SIZE);
821 static void draw_arrow(drawing *dr, game_drawstate *ds,
822 int x, int y, int xdx, int xdy, int cur)
825 int ydy = -xdx, ydx = xdy;
827 #define POINT(n, xx, yy) ( \
828 coords[2*(n)+0] = x + (xx)*xdx + (yy)*ydx, \
829 coords[2*(n)+1] = y + (xx)*xdy + (yy)*ydy)
831 POINT(0, TILE_SIZE / 2, 3 * TILE_SIZE / 4); /* top of arrow */
832 POINT(1, 3 * TILE_SIZE / 4, TILE_SIZE / 2); /* right corner */
833 POINT(2, 5 * TILE_SIZE / 8, TILE_SIZE / 2); /* right concave */
834 POINT(3, 5 * TILE_SIZE / 8, TILE_SIZE / 4); /* bottom right */
835 POINT(4, 3 * TILE_SIZE / 8, TILE_SIZE / 4); /* bottom left */
836 POINT(5, 3 * TILE_SIZE / 8, TILE_SIZE / 2); /* left concave */
837 POINT(6, TILE_SIZE / 4, TILE_SIZE / 2); /* left corner */
839 draw_polygon(dr, coords, 7, cur ? COL_HIGHLIGHT : COL_LOWLIGHT, COL_TEXT);
842 static void draw_arrow_for_cursor(drawing *dr, game_drawstate *ds,
843 int cur_x, int cur_y, int cur)
845 if (cur_x == -1 && cur_y == -1)
846 return; /* 'no cursur here */
847 else if (cur_x == -1) /* LH column. */
848 draw_arrow(dr, ds, COORD(0), COORD(cur_y+1), 0, -1, cur);
849 else if (cur_x == ds->w) /* RH column */
850 draw_arrow(dr, ds, COORD(ds->w), COORD(cur_y), 0, +1, cur);
851 else if (cur_y == -1) /* Top row */
852 draw_arrow(dr, ds, COORD(cur_x), COORD(0), +1, 0, cur);
853 else if (cur_y == ds->h) /* Bottom row */
854 draw_arrow(dr, ds, COORD(cur_x+1), COORD(ds->h), -1, 0, cur);
856 assert(!"Invalid cursor position");
858 draw_update(dr, COORD(cur_x), COORD(cur_y),
859 TILE_SIZE, TILE_SIZE);
862 static void game_redraw(drawing *dr, game_drawstate *ds,
863 const game_state *oldstate, const game_state *state,
864 int dir, const game_ui *ui,
865 float animtime, float flashtime)
868 int cur_x = -1, cur_y = -1;
871 int frame = (int)(flashtime / FLASH_FRAME);
872 bgcolour = (frame % 2 ? COL_LOWLIGHT : COL_HIGHLIGHT);
874 bgcolour = COL_BACKGROUND;
880 TILE_SIZE * state->w + 2 * BORDER,
881 TILE_SIZE * state->h + 2 * BORDER, COL_BACKGROUND);
882 draw_update(dr, 0, 0,
883 TILE_SIZE * state->w + 2 * BORDER,
884 TILE_SIZE * state->h + 2 * BORDER);
887 * Recessed area containing the whole puzzle.
889 coords[0] = COORD(state->w) + HIGHLIGHT_WIDTH - 1;
890 coords[1] = COORD(state->h) + HIGHLIGHT_WIDTH - 1;
891 coords[2] = COORD(state->w) + HIGHLIGHT_WIDTH - 1;
892 coords[3] = COORD(0) - HIGHLIGHT_WIDTH;
893 coords[4] = coords[2] - TILE_SIZE;
894 coords[5] = coords[3] + TILE_SIZE;
895 coords[8] = COORD(0) - HIGHLIGHT_WIDTH;
896 coords[9] = COORD(state->h) + HIGHLIGHT_WIDTH - 1;
897 coords[6] = coords[8] + TILE_SIZE;
898 coords[7] = coords[9] - TILE_SIZE;
899 draw_polygon(dr, coords, 5, COL_HIGHLIGHT, COL_HIGHLIGHT);
901 coords[1] = COORD(0) - HIGHLIGHT_WIDTH;
902 coords[0] = COORD(0) - HIGHLIGHT_WIDTH;
903 draw_polygon(dr, coords, 5, COL_LOWLIGHT, COL_LOWLIGHT);
906 * Arrows for making moves.
908 for (i = 0; i < state->w; i++) {
909 draw_arrow(dr, ds, COORD(i), COORD(0), +1, 0, 0);
910 draw_arrow(dr, ds, COORD(i+1), COORD(state->h), -1, 0, 0);
912 for (i = 0; i < state->h; i++) {
913 draw_arrow(dr, ds, COORD(state->w), COORD(i), 0, +1, 0);
914 draw_arrow(dr, ds, COORD(0), COORD(i+1), 0, -1, 0);
920 * Cursor (highlighted arrow around edge)
922 if (ui->cur_visible) {
923 cur_x = ui->cur_x; cur_y = ui->cur_y;
925 if (cur_x != ds->cur_x || cur_y != ds->cur_y) {
926 /* Cursor has changed; redraw two (prev and curr) arrows. */
927 draw_arrow_for_cursor(dr, ds, cur_x, cur_y, 1);
928 draw_arrow_for_cursor(dr, ds, ds->cur_x, ds->cur_y, 0);
929 ds->cur_x = cur_x; ds->cur_y = cur_y;
933 * Now draw each tile.
936 clip(dr, COORD(0), COORD(0), TILE_SIZE*state->w, TILE_SIZE*state->h);
938 for (i = 0; i < state->n; i++) {
941 * Figure out what should be displayed at this
942 * location. It's either a simple tile, or it's a
943 * transition between two tiles (in which case we say
944 * -1 because it must always be drawn).
947 if (oldstate && oldstate->tiles[i] != state->tiles[i])
954 if (ds->bgcolour != bgcolour || /* always redraw when flashing */
955 ds->tiles[i] != t || ds->tiles[i] == -1 || t == -1) {
959 * Figure out what to _actually_ draw, and where to
963 int x0, y0, x1, y1, dx, dy;
970 sense = -oldstate->last_movement_sense;
972 sense = state->last_movement_sense;
978 * FIXME: must be prepared to draw a double
979 * tile in some situations.
983 * Find the coordinates of this tile in the old and
986 x1 = COORD(X(state, i));
987 y1 = COORD(Y(state, i));
988 for (j = 0; j < oldstate->n; j++)
989 if (oldstate->tiles[j] == state->tiles[i])
991 assert(j < oldstate->n);
992 x0 = COORD(X(state, j));
993 y0 = COORD(Y(state, j));
997 dx != TILE_SIZE * sense) {
998 dx = (dx < 0 ? dx + TILE_SIZE * state->w :
999 dx - TILE_SIZE * state->w);
1000 assert(abs(dx) == TILE_SIZE);
1004 dy != TILE_SIZE * sense) {
1005 dy = (dy < 0 ? dy + TILE_SIZE * state->h :
1006 dy - TILE_SIZE * state->h);
1007 assert(abs(dy) == TILE_SIZE);
1010 c = (animtime / ANIM_TIME);
1011 if (c < 0.0F) c = 0.0F;
1012 if (c > 1.0F) c = 1.0F;
1014 x = x0 + (int)(c * dx);
1015 y = y0 + (int)(c * dy);
1016 x2 = x1 - dx + (int)(c * dx);
1017 y2 = y1 - dy + (int)(c * dy);
1019 x = COORD(X(state, i));
1020 y = COORD(Y(state, i));
1024 draw_tile(dr, ds, state, x, y, t, bgcolour);
1025 if (x2 != -1 || y2 != -1)
1026 draw_tile(dr, ds, state, x2, y2, t, bgcolour);
1033 ds->bgcolour = bgcolour;
1036 * Update the status bar.
1039 char statusbuf[256];
1042 * Don't show the new status until we're also showing the
1043 * new _state_ - after the game animation is complete.
1048 if (state->used_solve)
1049 sprintf(statusbuf, "Moves since auto-solve: %d",
1050 state->movecount - state->completed);
1052 sprintf(statusbuf, "%sMoves: %d",
1053 (state->completed ? "COMPLETED! " : ""),
1054 (state->completed ? state->completed : state->movecount));
1055 if (state->movetarget)
1056 sprintf(statusbuf+strlen(statusbuf), " (target %d)",
1060 status_bar(dr, statusbuf);
1064 static float game_anim_length(const game_state *oldstate,
1065 const game_state *newstate, int dir, game_ui *ui)
1070 static float game_flash_length(const game_state *oldstate,
1071 const game_state *newstate, int dir, game_ui *ui)
1073 if (!oldstate->completed && newstate->completed &&
1074 !oldstate->used_solve && !newstate->used_solve)
1075 return 2 * FLASH_FRAME;
1080 static int game_status(const game_state *state)
1082 return state->completed ? +1 : 0;
1085 static int game_timing_state(const game_state *state, game_ui *ui)
1090 static void game_print_size(const game_params *params, float *x, float *y)
1094 static void game_print(drawing *dr, const game_state *state, int tilesize)
1099 #define thegame sixteen
1102 const struct game thegame = {
1103 "Sixteen", "games.sixteen", "sixteen",
1110 TRUE, game_configure, custom_params,
1118 TRUE, game_can_format_as_text_now, game_text_format,
1126 PREFERRED_TILE_SIZE, game_compute_size, game_set_size,
1129 game_free_drawstate,
1134 FALSE, FALSE, game_print_size, game_print,
1135 TRUE, /* wants_statusbar */
1136 FALSE, game_timing_state,
1140 /* vim: set shiftwidth=4 tabstop=8: */