Files
puzzles/sixteen.c
Simon Tatham 751d7a2524 solve_game() is passed the _initial_ game state, not the most recent
one; so we can't just set `ret->completed = ret->movecount' and hope
it's been set to something other than zero. Instead, we set both
move counts to 1, which is entirely arbitrary but works.

This fixes a subtle bug with the Solve feature: if you pressed
Solve, then disturbed the grid, then brought it back to the solved
state by making more forward moves (rather than using Undo), then
the first time you did this the `Moves since auto-solve' status line
would reset to zero.

[originally from svn r5759]
2005-05-07 16:07:26 +00:00

887 lines
20 KiB
C

/*
* sixteen.c: `16-puzzle', a sliding-tiles jigsaw which differs
* from the 15-puzzle in that you toroidally rotate a row or column
* at a time.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <ctype.h>
#include <math.h>
#include "puzzles.h"
#define TILE_SIZE 48
#define BORDER TILE_SIZE /* big border to fill with arrows */
#define HIGHLIGHT_WIDTH (TILE_SIZE / 20)
#define COORD(x) ( (x) * TILE_SIZE + BORDER )
#define FROMCOORD(x) ( ((x) - BORDER + 2*TILE_SIZE) / TILE_SIZE - 2 )
#define ANIM_TIME 0.13F
#define FLASH_FRAME 0.13F
#define X(state, i) ( (i) % (state)->w )
#define Y(state, i) ( (i) / (state)->w )
#define C(state, x, y) ( (y) * (state)->w + (x) )
enum {
COL_BACKGROUND,
COL_TEXT,
COL_HIGHLIGHT,
COL_LOWLIGHT,
NCOLOURS
};
struct game_params {
int w, h;
};
struct game_state {
int w, h, n;
int *tiles;
int completed;
int just_used_solve; /* used to suppress undo animation */
int used_solve; /* used to suppress completion flash */
int movecount;
int last_movement_sense;
};
static game_params *default_params(void)
{
game_params *ret = snew(game_params);
ret->w = ret->h = 4;
return ret;
}
static int game_fetch_preset(int i, char **name, game_params **params)
{
game_params *ret;
int w, h;
char buf[80];
switch (i) {
case 0: w = 3, h = 3; break;
case 1: w = 4, h = 3; break;
case 2: w = 4, h = 4; break;
case 3: w = 5, h = 4; break;
case 4: w = 5, h = 5; break;
default: return FALSE;
}
sprintf(buf, "%dx%d", w, h);
*name = dupstr(buf);
*params = ret = snew(game_params);
ret->w = w;
ret->h = h;
return TRUE;
}
static void free_params(game_params *params)
{
sfree(params);
}
static game_params *dup_params(game_params *params)
{
game_params *ret = snew(game_params);
*ret = *params; /* structure copy */
return ret;
}
static game_params *decode_params(char const *string)
{
game_params *ret = default_params();
ret->w = ret->h = atoi(string);
while (*string && isdigit(*string)) string++;
if (*string == 'x') {
string++;
ret->h = atoi(string);
}
return ret;
}
static char *encode_params(game_params *params)
{
char data[256];
sprintf(data, "%dx%d", params->w, params->h);
return dupstr(data);
}
static config_item *game_configure(game_params *params)
{
config_item *ret;
char buf[80];
ret = snewn(3, config_item);
ret[0].name = "Width";
ret[0].type = C_STRING;
sprintf(buf, "%d", params->w);
ret[0].sval = dupstr(buf);
ret[0].ival = 0;
ret[1].name = "Height";
ret[1].type = C_STRING;
sprintf(buf, "%d", params->h);
ret[1].sval = dupstr(buf);
ret[1].ival = 0;
ret[2].name = NULL;
ret[2].type = C_END;
ret[2].sval = NULL;
ret[2].ival = 0;
return ret;
}
static game_params *custom_params(config_item *cfg)
{
game_params *ret = snew(game_params);
ret->w = atoi(cfg[0].sval);
ret->h = atoi(cfg[1].sval);
return ret;
}
static char *validate_params(game_params *params)
{
if (params->w < 2 && params->h < 2)
return "Width and height must both be at least two";
return NULL;
}
static int perm_parity(int *perm, int n)
{
int i, j, ret;
ret = 0;
for (i = 0; i < n-1; i++)
for (j = i+1; j < n; j++)
if (perm[i] > perm[j])
ret = !ret;
return ret;
}
static char *new_game_seed(game_params *params, random_state *rs,
game_aux_info **aux)
{
int stop, n, i, x;
int x1, x2, p1, p2;
int *tiles, *used;
char *ret;
int retlen;
n = params->w * params->h;
tiles = snewn(n, int);
used = snewn(n, int);
for (i = 0; i < n; i++) {
tiles[i] = -1;
used[i] = FALSE;
}
/*
* If both dimensions are odd, there is a parity constraint.
*/
if (params->w & params->h & 1)
stop = 2;
else
stop = 0;
/*
* Place everything except (possibly) the last two tiles.
*/
for (x = 0, i = n; i > stop; i--) {
int k = i > 1 ? random_upto(rs, i) : 0;
int j;
for (j = 0; j < n; j++)
if (!used[j] && (k-- == 0))
break;
assert(j < n && !used[j]);
used[j] = TRUE;
while (tiles[x] >= 0)
x++;
assert(x < n);
tiles[x] = j;
}
if (stop) {
/*
* Find the last two locations, and the last two pieces.
*/
while (tiles[x] >= 0)
x++;
assert(x < n);
x1 = x;
x++;
while (tiles[x] >= 0)
x++;
assert(x < n);
x2 = x;
for (i = 0; i < n; i++)
if (!used[i])
break;
p1 = i;
for (i = p1+1; i < n; i++)
if (!used[i])
break;
p2 = i;
/*
* Try the last two tiles one way round. If that fails, swap
* them.
*/
tiles[x1] = p1;
tiles[x2] = p2;
if (perm_parity(tiles, n) != 0) {
tiles[x1] = p2;
tiles[x2] = p1;
assert(perm_parity(tiles, n) == 0);
}
}
/*
* Now construct the game seed, by describing the tile array as
* a simple sequence of comma-separated integers.
*/
ret = NULL;
retlen = 0;
for (i = 0; i < n; i++) {
char buf[80];
int k;
k = sprintf(buf, "%d,", tiles[i]+1);
ret = sresize(ret, retlen + k + 1, char);
strcpy(ret + retlen, buf);
retlen += k;
}
ret[retlen-1] = '\0'; /* delete last comma */
sfree(tiles);
sfree(used);
return ret;
}
static void game_free_aux_info(game_aux_info *aux)
{
assert(!"Shouldn't happen");
}
static char *validate_seed(game_params *params, char *seed)
{
char *p, *err;
int i, area;
int *used;
area = params->w * params->h;
p = seed;
err = NULL;
used = snewn(area, int);
for (i = 0; i < area; i++)
used[i] = FALSE;
for (i = 0; i < area; i++) {
char *q = p;
int n;
if (*p < '0' || *p > '9') {
err = "Not enough numbers in string";
goto leave;
}
while (*p >= '0' && *p <= '9')
p++;
if (i < area-1 && *p != ',') {
err = "Expected comma after number";
goto leave;
}
else if (i == area-1 && *p) {
err = "Excess junk at end of string";
goto leave;
}
n = atoi(q);
if (n < 1 || n > area) {
err = "Number out of range";
goto leave;
}
if (used[n-1]) {
err = "Number used twice";
goto leave;
}
used[n-1] = TRUE;
if (*p) p++; /* eat comma */
}
leave:
sfree(used);
return err;
}
static game_state *new_game(game_params *params, char *seed)
{
game_state *state = snew(game_state);
int i;
char *p;
state->w = params->w;
state->h = params->h;
state->n = params->w * params->h;
state->tiles = snewn(state->n, int);
p = seed;
i = 0;
for (i = 0; i < state->n; i++) {
assert(*p);
state->tiles[i] = atoi(p);
while (*p && *p != ',')
p++;
if (*p) p++; /* eat comma */
}
assert(!*p);
state->completed = state->movecount = 0;
state->used_solve = state->just_used_solve = FALSE;
state->last_movement_sense = 0;
return state;
}
static game_state *dup_game(game_state *state)
{
game_state *ret = snew(game_state);
ret->w = state->w;
ret->h = state->h;
ret->n = state->n;
ret->tiles = snewn(state->w * state->h, int);
memcpy(ret->tiles, state->tiles, state->w * state->h * sizeof(int));
ret->completed = state->completed;
ret->movecount = state->movecount;
ret->used_solve = state->used_solve;
ret->just_used_solve = state->just_used_solve;
ret->last_movement_sense = state->last_movement_sense;
return ret;
}
static void free_game(game_state *state)
{
sfree(state);
}
static game_state *solve_game(game_state *state, game_aux_info *aux,
char **error)
{
game_state *ret = dup_game(state);
int i;
/*
* Simply replace the grid with a solved one. For this game,
* this isn't a useful operation for actually telling the user
* what they should have done, but it is useful for
* conveniently being able to get hold of a clean state from
* which to practise manoeuvres.
*/
for (i = 0; i < ret->n; i++)
ret->tiles[i] = i+1;
ret->used_solve = ret->just_used_solve = TRUE;
ret->completed = ret->movecount = 1;
return ret;
}
static char *game_text_format(game_state *state)
{
char *ret, *p, buf[80];
int x, y, col, maxlen;
/*
* First work out how many characters we need to display each
* number.
*/
col = sprintf(buf, "%d", state->n);
/*
* Now we know the exact total size of the grid we're going to
* produce: it's got h rows, each containing w lots of col, w-1
* spaces and a trailing newline.
*/
maxlen = state->h * state->w * (col+1);
ret = snewn(maxlen+1, char);
p = ret;
for (y = 0; y < state->h; y++) {
for (x = 0; x < state->w; x++) {
int v = state->tiles[state->w*y+x];
sprintf(buf, "%*d", col, v);
memcpy(p, buf, col);
p += col;
if (x+1 == state->w)
*p++ = '\n';
else
*p++ = ' ';
}
}
assert(p - ret == maxlen);
*p = '\0';
return ret;
}
static game_ui *new_ui(game_state *state)
{
return NULL;
}
static void free_ui(game_ui *ui)
{
}
static game_state *make_move(game_state *from, game_ui *ui,
int x, int y, int button)
{
int cx, cy;
int dx, dy, tx, ty, n;
game_state *ret;
if (button != LEFT_BUTTON && button != RIGHT_BUTTON)
return NULL;
cx = FROMCOORD(x);
cy = FROMCOORD(y);
if (cx == -1 && cy >= 0 && cy < from->h)
n = from->w, dx = +1, dy = 0;
else if (cx == from->w && cy >= 0 && cy < from->h)
n = from->w, dx = -1, dy = 0;
else if (cy == -1 && cx >= 0 && cx < from->w)
n = from->h, dy = +1, dx = 0;
else if (cy == from->h && cx >= 0 && cx < from->w)
n = from->h, dy = -1, dx = 0;
else
return NULL; /* invalid click location */
/* reverse direction if right hand button is pressed */
if (button == RIGHT_BUTTON)
{
dx = -dx; if (dx) cx = from->w - 1 - cx;
dy = -dy; if (dy) cy = from->h - 1 - cy;
}
ret = dup_game(from);
ret->just_used_solve = FALSE; /* zero this in a hurry */
do {
cx += dx;
cy += dy;
tx = (cx + dx + from->w) % from->w;
ty = (cy + dy + from->h) % from->h;
ret->tiles[C(ret, cx, cy)] = from->tiles[C(from, tx, ty)];
} while (--n > 0);
ret->movecount++;
ret->last_movement_sense = -(dx+dy);
/*
* See if the game has been completed.
*/
if (!ret->completed) {
ret->completed = ret->movecount;
for (n = 0; n < ret->n; n++)
if (ret->tiles[n] != n+1)
ret->completed = FALSE;
}
return ret;
}
/* ----------------------------------------------------------------------
* Drawing routines.
*/
struct game_drawstate {
int started;
int w, h, bgcolour;
int *tiles;
};
static void game_size(game_params *params, int *x, int *y)
{
*x = TILE_SIZE * params->w + 2 * BORDER;
*y = TILE_SIZE * params->h + 2 * BORDER;
}
static float *game_colours(frontend *fe, game_state *state, int *ncolours)
{
float *ret = snewn(3 * NCOLOURS, float);
int i;
float max;
frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
/*
* Drop the background colour so that the highlight is
* noticeably brighter than it while still being under 1.
*/
max = ret[COL_BACKGROUND*3];
for (i = 1; i < 3; i++)
if (ret[COL_BACKGROUND*3+i] > max)
max = ret[COL_BACKGROUND*3+i];
if (max * 1.2F > 1.0F) {
for (i = 0; i < 3; i++)
ret[COL_BACKGROUND*3+i] /= (max * 1.2F);
}
for (i = 0; i < 3; i++) {
ret[COL_HIGHLIGHT * 3 + i] = ret[COL_BACKGROUND * 3 + i] * 1.2F;
ret[COL_LOWLIGHT * 3 + i] = ret[COL_BACKGROUND * 3 + i] * 0.8F;
ret[COL_TEXT * 3 + i] = 0.0;
}
*ncolours = NCOLOURS;
return ret;
}
static game_drawstate *game_new_drawstate(game_state *state)
{
struct game_drawstate *ds = snew(struct game_drawstate);
int i;
ds->started = FALSE;
ds->w = state->w;
ds->h = state->h;
ds->bgcolour = COL_BACKGROUND;
ds->tiles = snewn(ds->w*ds->h, int);
for (i = 0; i < ds->w*ds->h; i++)
ds->tiles[i] = -1;
return ds;
}
static void game_free_drawstate(game_drawstate *ds)
{
sfree(ds->tiles);
sfree(ds);
}
static void draw_tile(frontend *fe, game_state *state, int x, int y,
int tile, int flash_colour)
{
if (tile == 0) {
draw_rect(fe, x, y, TILE_SIZE, TILE_SIZE,
flash_colour);
} else {
int coords[6];
char str[40];
coords[0] = x + TILE_SIZE - 1;
coords[1] = y + TILE_SIZE - 1;
coords[2] = x + TILE_SIZE - 1;
coords[3] = y;
coords[4] = x;
coords[5] = y + TILE_SIZE - 1;
draw_polygon(fe, coords, 3, TRUE, COL_LOWLIGHT);
draw_polygon(fe, coords, 3, FALSE, COL_LOWLIGHT);
coords[0] = x;
coords[1] = y;
draw_polygon(fe, coords, 3, TRUE, COL_HIGHLIGHT);
draw_polygon(fe, coords, 3, FALSE, COL_HIGHLIGHT);
draw_rect(fe, x + HIGHLIGHT_WIDTH, y + HIGHLIGHT_WIDTH,
TILE_SIZE - 2*HIGHLIGHT_WIDTH, TILE_SIZE - 2*HIGHLIGHT_WIDTH,
flash_colour);
sprintf(str, "%d", tile);
draw_text(fe, x + TILE_SIZE/2, y + TILE_SIZE/2,
FONT_VARIABLE, TILE_SIZE/3, ALIGN_VCENTRE | ALIGN_HCENTRE,
COL_TEXT, str);
}
draw_update(fe, x, y, TILE_SIZE, TILE_SIZE);
}
static void draw_arrow(frontend *fe, int x, int y, int xdx, int xdy)
{
int coords[14];
int ydy = -xdx, ydx = xdy;
#define POINT(n, xx, yy) ( \
coords[2*(n)+0] = x + (xx)*xdx + (yy)*ydx, \
coords[2*(n)+1] = y + (xx)*xdy + (yy)*ydy)
POINT(0, TILE_SIZE / 2, 3 * TILE_SIZE / 4); /* top of arrow */
POINT(1, 3 * TILE_SIZE / 4, TILE_SIZE / 2); /* right corner */
POINT(2, 5 * TILE_SIZE / 8, TILE_SIZE / 2); /* right concave */
POINT(3, 5 * TILE_SIZE / 8, TILE_SIZE / 4); /* bottom right */
POINT(4, 3 * TILE_SIZE / 8, TILE_SIZE / 4); /* bottom left */
POINT(5, 3 * TILE_SIZE / 8, TILE_SIZE / 2); /* left concave */
POINT(6, TILE_SIZE / 4, TILE_SIZE / 2); /* left corner */
draw_polygon(fe, coords, 7, TRUE, COL_LOWLIGHT);
draw_polygon(fe, coords, 7, FALSE, COL_TEXT);
}
static void game_redraw(frontend *fe, game_drawstate *ds, game_state *oldstate,
game_state *state, int dir, game_ui *ui,
float animtime, float flashtime)
{
int i, bgcolour;
if (flashtime > 0) {
int frame = (int)(flashtime / FLASH_FRAME);
bgcolour = (frame % 2 ? COL_LOWLIGHT : COL_HIGHLIGHT);
} else
bgcolour = COL_BACKGROUND;
if (!ds->started) {
int coords[6];
draw_rect(fe, 0, 0,
TILE_SIZE * state->w + 2 * BORDER,
TILE_SIZE * state->h + 2 * BORDER, COL_BACKGROUND);
draw_update(fe, 0, 0,
TILE_SIZE * state->w + 2 * BORDER,
TILE_SIZE * state->h + 2 * BORDER);
/*
* Recessed area containing the whole puzzle.
*/
coords[0] = COORD(state->w) + HIGHLIGHT_WIDTH - 1;
coords[1] = COORD(state->h) + HIGHLIGHT_WIDTH - 1;
coords[2] = COORD(state->w) + HIGHLIGHT_WIDTH - 1;
coords[3] = COORD(0) - HIGHLIGHT_WIDTH;
coords[4] = COORD(0) - HIGHLIGHT_WIDTH;
coords[5] = COORD(state->h) + HIGHLIGHT_WIDTH - 1;
draw_polygon(fe, coords, 3, TRUE, COL_HIGHLIGHT);
draw_polygon(fe, coords, 3, FALSE, COL_HIGHLIGHT);
coords[1] = COORD(0) - HIGHLIGHT_WIDTH;
coords[0] = COORD(0) - HIGHLIGHT_WIDTH;
draw_polygon(fe, coords, 3, TRUE, COL_LOWLIGHT);
draw_polygon(fe, coords, 3, FALSE, COL_LOWLIGHT);
/*
* Arrows for making moves.
*/
for (i = 0; i < state->w; i++) {
draw_arrow(fe, COORD(i), COORD(0), +1, 0);
draw_arrow(fe, COORD(i+1), COORD(state->h), -1, 0);
}
for (i = 0; i < state->h; i++) {
draw_arrow(fe, COORD(state->w), COORD(i), 0, +1);
draw_arrow(fe, COORD(0), COORD(i+1), 0, -1);
}
ds->started = TRUE;
}
/*
* Now draw each tile.
*/
clip(fe, COORD(0), COORD(0), TILE_SIZE*state->w, TILE_SIZE*state->h);
for (i = 0; i < state->n; i++) {
int t, t0;
/*
* Figure out what should be displayed at this
* location. It's either a simple tile, or it's a
* transition between two tiles (in which case we say
* -1 because it must always be drawn).
*/
if (oldstate && oldstate->tiles[i] != state->tiles[i])
t = -1;
else
t = state->tiles[i];
t0 = t;
if (ds->bgcolour != bgcolour || /* always redraw when flashing */
ds->tiles[i] != t || ds->tiles[i] == -1 || t == -1) {
int x, y, x2, y2;
/*
* Figure out what to _actually_ draw, and where to
* draw it.
*/
if (t == -1) {
int x0, y0, x1, y1, dx, dy;
int j;
float c;
int sense;
if (dir < 0) {
assert(oldstate);
sense = -oldstate->last_movement_sense;
} else {
sense = state->last_movement_sense;
}
t = state->tiles[i];
/*
* FIXME: must be prepared to draw a double
* tile in some situations.
*/
/*
* Find the coordinates of this tile in the old and
* new states.
*/
x1 = COORD(X(state, i));
y1 = COORD(Y(state, i));
for (j = 0; j < oldstate->n; j++)
if (oldstate->tiles[j] == state->tiles[i])
break;
assert(j < oldstate->n);
x0 = COORD(X(state, j));
y0 = COORD(Y(state, j));
dx = (x1 - x0);
if (dx != 0 &&
dx != TILE_SIZE * sense) {
dx = (dx < 0 ? dx + TILE_SIZE * state->w :
dx - TILE_SIZE * state->w);
assert(abs(dx) == TILE_SIZE);
}
dy = (y1 - y0);
if (dy != 0 &&
dy != TILE_SIZE * sense) {
dy = (dy < 0 ? dy + TILE_SIZE * state->h :
dy - TILE_SIZE * state->h);
assert(abs(dy) == TILE_SIZE);
}
c = (animtime / ANIM_TIME);
if (c < 0.0F) c = 0.0F;
if (c > 1.0F) c = 1.0F;
x = x0 + (int)(c * dx);
y = y0 + (int)(c * dy);
x2 = x1 - dx + (int)(c * dx);
y2 = y1 - dy + (int)(c * dy);
} else {
x = COORD(X(state, i));
y = COORD(Y(state, i));
x2 = y2 = -1;
}
draw_tile(fe, state, x, y, t, bgcolour);
if (x2 != -1 || y2 != -1)
draw_tile(fe, state, x2, y2, t, bgcolour);
}
ds->tiles[i] = t0;
}
unclip(fe);
ds->bgcolour = bgcolour;
/*
* Update the status bar.
*/
{
char statusbuf[256];
/*
* Don't show the new status until we're also showing the
* new _state_ - after the game animation is complete.
*/
if (oldstate)
state = oldstate;
if (state->used_solve)
sprintf(statusbuf, "Moves since auto-solve: %d",
state->movecount - state->completed);
else
sprintf(statusbuf, "%sMoves: %d",
(state->completed ? "COMPLETED! " : ""),
(state->completed ? state->completed : state->movecount));
status_bar(fe, statusbuf);
}
}
static float game_anim_length(game_state *oldstate,
game_state *newstate, int dir)
{
if ((dir > 0 && newstate->just_used_solve) ||
(dir < 0 && oldstate->just_used_solve))
return 0.0F;
else
return ANIM_TIME;
}
static float game_flash_length(game_state *oldstate,
game_state *newstate, int dir)
{
if (!oldstate->completed && newstate->completed &&
!oldstate->used_solve && !newstate->used_solve)
return 2 * FLASH_FRAME;
else
return 0.0F;
}
static int game_wants_statusbar(void)
{
return TRUE;
}
#ifdef COMBINED
#define thegame sixteen
#endif
const struct game thegame = {
"Sixteen", "games.sixteen",
default_params,
game_fetch_preset,
decode_params,
encode_params,
free_params,
dup_params,
TRUE, game_configure, custom_params,
validate_params,
new_game_seed,
game_free_aux_info,
validate_seed,
new_game,
dup_game,
free_game,
TRUE, solve_game,
TRUE, game_text_format,
new_ui,
free_ui,
make_move,
game_size,
game_colours,
game_new_drawstate,
game_free_drawstate,
game_redraw,
game_anim_length,
game_flash_length,
game_wants_statusbar,
};