Files
puzzles/sixteen.c
Simon Tatham 9e240e45df Introduce the concept of a `game_aux_info' structure. This is
constructed at the same time as an internally generated game seed,
so that it can preserve any interesting information known by the
program at generation time but not physically contained within the
text of the game seed itself. (Such as, for example, the solution.)
Currently not used for anything yet, but it will be.

[originally from svn r5729]
2005-05-02 10:12:26 +00:00

850 lines
19 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 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;
}
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->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->last_movement_sense = state->last_movement_sense;
return ret;
}
static void free_game(game_state *state)
{
sfree(state);
}
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, 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);
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;
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)
{
return ANIM_TIME;
}
static float game_flash_length(game_state *oldstate,
game_state *newstate, int dir)
{
if (!oldstate->completed && newstate->completed)
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, 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,
};