[sgt/puzzles] / sixteen.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)
{
    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 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 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", TRUE,
    default_params,
    game_fetch_preset,
    decode_params,
    encode_params,
    free_params,
    dup_params,
    game_configure,
    custom_params,
    validate_params,
    new_game_seed,
    validate_seed,
    new_game,
    dup_game,
    free_game,
    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,
};
Commit	Line	Data
4efb3868	1	/*
	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
	4	* at a time.
	5	*/
	6
	7	#include <stdio.h>
	8	#include <stdlib.h>
	9	#include <string.h>
	10	#include <assert.h>
b0e26073	11	#include <ctype.h>
4efb3868	12	#include <math.h>
	13
	14	#include "puzzles.h"
	15
4efb3868	16	#define TILE_SIZE 48
	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 )
	21
8c1fd974	22	#define ANIM_TIME 0.13F
8c1fd974	23	#define FLASH_FRAME 0.13F
4efb3868	24
	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) )
	28
	29	enum {
	30	COL_BACKGROUND,
	31	COL_TEXT,
	32	COL_HIGHLIGHT,
	33	COL_LOWLIGHT,
	34	NCOLOURS
	35	};
	36
	37	struct game_params {
	38	int w, h;
	39	};
	40
	41	struct game_state {
	42	int w, h, n;
	43	int *tiles;
	44	int completed;
fd1a1a2b	45	int movecount;
c8230524	46	int last_movement_sense;
4efb3868	47	};
4efb3868	48
be8d5aa1	49	static game_params *default_params(void)
4efb3868	50	{
	51	game_params *ret = snew(game_params);
	52
	53	ret->w = ret->h = 4;
	54
	55	return ret;
	56	}
	57
be8d5aa1	58	static int game_fetch_preset(int i, char name, game_params params)
4efb3868	59	{
	60	game_params *ret;
	61	int w, h;
	62	char buf[80];
	63
	64	switch (i) {
	65	case 0: w = 3, h = 3; break;
	66	case 1: w = 4, h = 3; break;
	67	case 2: w = 4, h = 4; break;
	68	case 3: w = 5, h = 4; break;
	69	case 4: w = 5, h = 5; break;
	70	default: return FALSE;
	71	}
	72
	73	sprintf(buf, "%dx%d", w, h);
	74	*name = dupstr(buf);
	75	*params = ret = snew(game_params);
	76	ret->w = w;
	77	ret->h = h;
	78	return TRUE;
	79	}
	80
be8d5aa1	81	static void free_params(game_params *params)
4efb3868	82	{
	83	sfree(params);
	84	}
	85
be8d5aa1	86	static game_params dup_params(game_params params)
4efb3868	87	{
	88	game_params *ret = snew(game_params);
	89	ret = params; /* structure copy */
	90	return ret;
	91	}
	92
be8d5aa1	93	static game_params decode_params(char const string)
b0e26073	94	{
	95	game_params *ret = default_params();
	96
	97	ret->w = ret->h = atoi(string);
	98	while (string && isdigit(string)) string++;
	99	if (*string == 'x') {
	100	string++;
	101	ret->h = atoi(string);
	102	}
	103
	104	return ret;
	105	}
	106
be8d5aa1	107	static char encode_params(game_params params)
b0e26073	108	{
	109	char data[256];
	110
	111	sprintf(data, "%dx%d", params->w, params->h);
	112
	113	return dupstr(data);
	114	}
	115
be8d5aa1	116	static config_item game_configure(game_params params)
c8230524	117	{
	118	config_item *ret;
	119	char buf[80];
	120
	121	ret = snewn(3, config_item);
	122
	123	ret[0].name = "Width";
95709966	124	ret[0].type = C_STRING;
c8230524	125	sprintf(buf, "%d", params->w);
	126	ret[0].sval = dupstr(buf);
	127	ret[0].ival = 0;
	128
	129	ret[1].name = "Height";
95709966	130	ret[1].type = C_STRING;
c8230524	131	sprintf(buf, "%d", params->h);
	132	ret[1].sval = dupstr(buf);
	133	ret[1].ival = 0;
	134
	135	ret[2].name = NULL;
95709966	136	ret[2].type = C_END;
c8230524	137	ret[2].sval = NULL;
	138	ret[2].ival = 0;
	139
	140	return ret;
	141	}
	142
be8d5aa1	143	static game_params custom_params(config_item cfg)
c8230524	144	{
	145	game_params *ret = snew(game_params);
	146
	147	ret->w = atoi(cfg[0].sval);
	148	ret->h = atoi(cfg[1].sval);
	149
	150	return ret;
	151	}
	152
be8d5aa1	153	static char validate_params(game_params params)
c8230524	154	{
	155	if (params->w < 2 && params->h < 2)
	156	return "Width and height must both be at least two";
	157
	158	return NULL;
	159	}
	160
be8d5aa1	161	static int perm_parity(int *perm, int n)
4efb3868	162	{
	163	int i, j, ret;
	164
	165	ret = 0;
	166
	167	for (i = 0; i < n-1; i++)
	168	for (j = i+1; j < n; j++)
	169	if (perm[i] > perm[j])
	170	ret = !ret;
	171
	172	return ret;
	173	}
	174
be8d5aa1	175	static char new_game_seed(game_params params, random_state *rs)
4efb3868	176	{
	177	int stop, n, i, x;
	178	int x1, x2, p1, p2;
	179	int tiles, used;
	180	char *ret;
	181	int retlen;
	182
	183	n = params->w * params->h;
	184
	185	tiles = snewn(n, int);
	186	used = snewn(n, int);
	187
	188	for (i = 0; i < n; i++) {
	189	tiles[i] = -1;
	190	used[i] = FALSE;
	191	}
	192
	193	/*
	194	* If both dimensions are odd, there is a parity constraint.
	195	*/
	196	if (params->w & params->h & 1)
	197	stop = 2;
	198	else
	199	stop = 0;
	200
	201	/*
	202	* Place everything except (possibly) the last two tiles.
	203	*/
	204	for (x = 0, i = n; i > stop; i--) {
48d70ca9	205	int k = i > 1 ? random_upto(rs, i) : 0;
4efb3868	206	int j;
	207
	208	for (j = 0; j < n; j++)
	209	if (!used[j] && (k-- == 0))
	210	break;
	211
	212	assert(j < n && !used[j]);
	213	used[j] = TRUE;
	214
	215	while (tiles[x] >= 0)
	216	x++;
	217	assert(x < n);
	218	tiles[x] = j;
	219	}
	220
	221	if (stop) {
	222	/*
	223	* Find the last two locations, and the last two pieces.
	224	*/
	225	while (tiles[x] >= 0)
	226	x++;
	227	assert(x < n);
	228	x1 = x;
	229	x++;
	230	while (tiles[x] >= 0)
	231	x++;
	232	assert(x < n);
	233	x2 = x;
	234
	235	for (i = 0; i < n; i++)
	236	if (!used[i])
	237	break;
	238	p1 = i;
	239	for (i = p1+1; i < n; i++)
	240	if (!used[i])
	241	break;
	242	p2 = i;
	243
	244	/*
	245	* Try the last two tiles one way round. If that fails, swap
	246	* them.
	247	*/
	248	tiles[x1] = p1;
	249	tiles[x2] = p2;
	250	if (perm_parity(tiles, n) != 0) {
	251	tiles[x1] = p2;
	252	tiles[x2] = p1;
	253	assert(perm_parity(tiles, n) == 0);
	254	}
	255	}
	256
	257	/*
	258	* Now construct the game seed, by describing the tile array as
	259	* a simple sequence of comma-separated integers.
	260	*/
	261	ret = NULL;
	262	retlen = 0;
	263	for (i = 0; i < n; i++) {
	264	char buf[80];
	265	int k;
	266
	267	k = sprintf(buf, "%d,", tiles[i]+1);
	268
	269	ret = sresize(ret, retlen + k + 1, char);
270	strcpy(ret + retlen, buf);
271	retlen += k;
272	}
273	ret[retlen-1] = '\0'; /* delete last comma */
274
275	sfree(tiles);
276	sfree(used);
277
278	return ret;
279	}
280
5928817c	281
be8d5aa1	282	static char validate_seed(game_params params, char *seed)
5928817c	283	{
	284	char p, err;
	285	int i, area;
	286	int *used;
	287
	288	area = params->w * params->h;
	289	p = seed;
	290	err = NULL;
	291
	292	used = snewn(area, int);
	293	for (i = 0; i < area; i++)
	294	used[i] = FALSE;
	295
	296	for (i = 0; i < area; i++) {
	297	char *q = p;
	298	int n;
	299
	300	if (p < '0' \|\| p > '9') {
	301	err = "Not enough numbers in string";
	302	goto leave;
	303	}
	304	while (p >= '0' && p <= '9')
	305	p++;
	306	if (i < area-1 && *p != ',') {
	307	err = "Expected comma after number";
	308	goto leave;
	309	}
	310	else if (i == area-1 && *p) {
	311	err = "Excess junk at end of string";
	312	goto leave;
	313	}
	314	n = atoi(q);
	315	if (n < 1 \|\| n > area) {
	316	err = "Number out of range";
	317	goto leave;
	318	}
	319	if (used[n-1]) {
	320	err = "Number used twice";
	321	goto leave;
	322	}
	323	used[n-1] = TRUE;
	324
	325	if (p) p++; / eat comma */
	326	}
	327
	328	leave:
	329	sfree(used);
	330	return err;
	331	}
	332
be8d5aa1	333	static game_state new_game(game_params params, char *seed)
4efb3868	334	{
	335	game_state *state = snew(game_state);
	336	int i;
	337	char *p;
	338
	339	state->w = params->w;
	340	state->h = params->h;
	341	state->n = params->w * params->h;
	342	state->tiles = snewn(state->n, int);
	343
	344	p = seed;
	345	i = 0;
	346	for (i = 0; i < state->n; i++) {
	347	assert(*p);
	348	state->tiles[i] = atoi(p);
	349	while (p && p != ',')
	350	p++;
	351	if (p) p++; / eat comma */
	352	}
	353	assert(!*p);
	354
fd1a1a2b	355	state->completed = state->movecount = 0;
c8230524	356	state->last_movement_sense = 0;
4efb3868	357
	358	return state;
	359	}
	360
be8d5aa1	361	static game_state dup_game(game_state state)
4efb3868	362	{
	363	game_state *ret = snew(game_state);
	364
	365	ret->w = state->w;
	366	ret->h = state->h;
	367	ret->n = state->n;
	368	ret->tiles = snewn(state->w * state->h, int);
	369	memcpy(ret->tiles, state->tiles, state->w * state->h * sizeof(int));
	370	ret->completed = state->completed;
fd1a1a2b	371	ret->movecount = state->movecount;
c8230524	372	ret->last_movement_sense = state->last_movement_sense;
4efb3868	373
	374	return ret;
	375	}
	376
be8d5aa1	377	static void free_game(game_state *state)
4efb3868	378	{
	379	sfree(state);
	380	}
	381
be8d5aa1	382	static game_ui new_ui(game_state state)
74a4e547	383	{
	384	return NULL;
	385	}
	386
be8d5aa1	387	static void free_ui(game_ui *ui)
74a4e547	388	{
	389	}
	390
be8d5aa1	391	static game_state make_move(game_state from, game_ui *ui,
be8d5aa1	392	int x, int y, int button)
4efb3868	393	{
	394	int cx, cy;
	395	int dx, dy, tx, ty, n;
	396	game_state *ret;
	397
e91825f8	398	if (button != LEFT_BUTTON && button != RIGHT_BUTTON)
4efb3868	399	return NULL;
	400
	401	cx = FROMCOORD(x);
	402	cy = FROMCOORD(y);
	403	if (cx == -1 && cy >= 0 && cy < from->h)
	404	n = from->w, dx = +1, dy = 0;
	405	else if (cx == from->w && cy >= 0 && cy < from->h)
	406	n = from->w, dx = -1, dy = 0;
	407	else if (cy == -1 && cx >= 0 && cx < from->w)
	408	n = from->h, dy = +1, dx = 0;
	409	else if (cy == from->h && cx >= 0 && cx < from->w)
	410	n = from->h, dy = -1, dx = 0;
	411	else
	412	return NULL; /* invalid click location */
	413
e91825f8	414	/* reverse direction if right hand button is pressed */
	415	if (button == RIGHT_BUTTON)
	416	{
	417	dx = -dx; if (dx) cx = from->w - 1 - cx;
	418	dy = -dy; if (dy) cy = from->h - 1 - cy;
	419	}
	420
4efb3868	421	ret = dup_game(from);
	422
	423	do {
	424	cx += dx;
	425	cy += dy;
	426	tx = (cx + dx + from->w) % from->w;
	427	ty = (cy + dy + from->h) % from->h;
	428	ret->tiles[C(ret, cx, cy)] = from->tiles[C(from, tx, ty)];
	429	} while (--n > 0);
	430
fd1a1a2b	431	ret->movecount++;
fd1a1a2b	432
c8230524	433	ret->last_movement_sense = -(dx+dy);
c8230524	434
4efb3868	435	/*
	436	* See if the game has been completed.
	437	*/
	438	if (!ret->completed) {
fd1a1a2b	439	ret->completed = ret->movecount;
4efb3868	440	for (n = 0; n < ret->n; n++)
	441	if (ret->tiles[n] != n+1)
	442	ret->completed = FALSE;
	443	}
	444
	445	return ret;
	446	}
	447
	448	/* ----------------------------------------------------------------------
	449	* Drawing routines.
	450	*/
	451
	452	struct game_drawstate {
	453	int started;
	454	int w, h, bgcolour;
	455	int *tiles;
	456	};
	457
be8d5aa1	458	static void game_size(game_params params, int x, int *y)
4efb3868	459	{
	460	x = TILE_SIZE params->w + 2 * BORDER;
	461	y = TILE_SIZE params->h + 2 * BORDER;
	462	}
	463
be8d5aa1	464	static float game_colours(frontend fe, game_state state, int ncolours)
4efb3868	465	{
	466	float ret = snewn(3 NCOLOURS, float);
	467	int i;
	468	float max;
	469
	470	frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
	471
	472	/*
	473	* Drop the background colour so that the highlight is
	474	* noticeably brighter than it while still being under 1.
	475	*/
	476	max = ret[COL_BACKGROUND*3];
	477	for (i = 1; i < 3; i++)
	478	if (ret[COL_BACKGROUND*3+i] > max)
	479	max = ret[COL_BACKGROUND*3+i];
	480	if (max * 1.2F > 1.0F) {
	481	for (i = 0; i < 3; i++)
	482	ret[COL_BACKGROUND3+i] /= (max 1.2F);
	483	}
	484
	485	for (i = 0; i < 3; i++) {
	486	ret[COL_HIGHLIGHT * 3 + i] = ret[COL_BACKGROUND * 3 + i] * 1.2F;
	487	ret[COL_LOWLIGHT * 3 + i] = ret[COL_BACKGROUND * 3 + i] * 0.8F;
	488	ret[COL_TEXT * 3 + i] = 0.0;
	489	}
	490
	491	*ncolours = NCOLOURS;
	492	return ret;
	493	}
	494
be8d5aa1	495	static game_drawstate game_new_drawstate(game_state state)
4efb3868	496	{
	497	struct game_drawstate *ds = snew(struct game_drawstate);
	498	int i;
	499
	500	ds->started = FALSE;
	501	ds->w = state->w;
	502	ds->h = state->h;
	503	ds->bgcolour = COL_BACKGROUND;
	504	ds->tiles = snewn(ds->w*ds->h, int);
	505	for (i = 0; i < ds->w*ds->h; i++)
	506	ds->tiles[i] = -1;
	507
	508	return ds;
	509	}
	510
be8d5aa1	511	static void game_free_drawstate(game_drawstate *ds)
4efb3868	512	{
	513	sfree(ds->tiles);
	514	sfree(ds);
	515	}
	516
	517	static void draw_tile(frontend fe, game_state state, int x, int y,
	518	int tile, int flash_colour)
	519	{
	520	if (tile == 0) {
	521	draw_rect(fe, x, y, TILE_SIZE, TILE_SIZE,
	522	flash_colour);
	523	} else {
	524	int coords[6];
	525	char str[40];
	526
	527	coords[0] = x + TILE_SIZE - 1;
	528	coords[1] = y + TILE_SIZE - 1;
	529	coords[2] = x + TILE_SIZE - 1;
	530	coords[3] = y;
	531	coords[4] = x;
	532	coords[5] = y + TILE_SIZE - 1;
	533	draw_polygon(fe, coords, 3, TRUE, COL_LOWLIGHT);
	534	draw_polygon(fe, coords, 3, FALSE, COL_LOWLIGHT);
	535
	536	coords[0] = x;
	537	coords[1] = y;
	538	draw_polygon(fe, coords, 3, TRUE, COL_HIGHLIGHT);
	539	draw_polygon(fe, coords, 3, FALSE, COL_HIGHLIGHT);
	540
	541	draw_rect(fe, x + HIGHLIGHT_WIDTH, y + HIGHLIGHT_WIDTH,
	542	TILE_SIZE - 2HIGHLIGHT_WIDTH, TILE_SIZE - 2HIGHLIGHT_WIDTH,
	543	flash_colour);
	544
	545	sprintf(str, "%d", tile);
	546	draw_text(fe, x + TILE_SIZE/2, y + TILE_SIZE/2,
	547	FONT_VARIABLE, TILE_SIZE/3, ALIGN_VCENTRE \| ALIGN_HCENTRE,
	548	COL_TEXT, str);
	549	}
	550	draw_update(fe, x, y, TILE_SIZE, TILE_SIZE);
	551	}
	552
	553	static void draw_arrow(frontend *fe, int x, int y, int xdx, int xdy)
	554	{
	555	int coords[14];
	556	int ydy = -xdx, ydx = xdy;
	557
	558	#define POINT(n, xx, yy) ( \
	559	coords[2(n)+0] = x + (xx)xdx + (yy)*ydx, \
	560	coords[2(n)+1] = y + (xx)xdy + (yy)*ydy)
	561
	562	POINT(0, TILE_SIZE / 2, 3 * TILE_SIZE / 4); /* top of arrow */
	563	POINT(1, 3 * TILE_SIZE / 4, TILE_SIZE / 2); /* right corner */
	564	POINT(2, 5 * TILE_SIZE / 8, TILE_SIZE / 2); /* right concave */
	565	POINT(3, 5 * TILE_SIZE / 8, TILE_SIZE / 4); /* bottom right */
	566	POINT(4, 3 * TILE_SIZE / 8, TILE_SIZE / 4); /* bottom left */
	567	POINT(5, 3 * TILE_SIZE / 8, TILE_SIZE / 2); /* left concave */
	568	POINT(6, TILE_SIZE / 4, TILE_SIZE / 2); /* left corner */
	569
	570	draw_polygon(fe, coords, 7, TRUE, COL_LOWLIGHT);
	571	draw_polygon(fe, coords, 7, FALSE, COL_TEXT);
	572	}
	573
be8d5aa1	574	static void game_redraw(frontend fe, game_drawstate ds, game_state *oldstate,
c822de4a	575	game_state state, int dir, game_ui ui,
74a4e547	576	float animtime, float flashtime)
4efb3868	577	{
b443c381	578	int i, bgcolour;
4efb3868	579
	580	if (flashtime > 0) {
	581	int frame = (int)(flashtime / FLASH_FRAME);
	582	bgcolour = (frame % 2 ? COL_LOWLIGHT : COL_HIGHLIGHT);
	583	} else
	584	bgcolour = COL_BACKGROUND;
	585
	586	if (!ds->started) {
	587	int coords[6];
	588
	589	draw_rect(fe, 0, 0,
	590	TILE_SIZE * state->w + 2 * BORDER,
	591	TILE_SIZE * state->h + 2 * BORDER, COL_BACKGROUND);
	592	draw_update(fe, 0, 0,
	593	TILE_SIZE * state->w + 2 * BORDER,
	594	TILE_SIZE * state->h + 2 * BORDER);
	595
	596	/*
	597	* Recessed area containing the whole puzzle.
	598	*/
	599	coords[0] = COORD(state->w) + HIGHLIGHT_WIDTH - 1;
	600	coords[1] = COORD(state->h) + HIGHLIGHT_WIDTH - 1;
	601	coords[2] = COORD(state->w) + HIGHLIGHT_WIDTH - 1;
	602	coords[3] = COORD(0) - HIGHLIGHT_WIDTH;
	603	coords[4] = COORD(0) - HIGHLIGHT_WIDTH;
	604	coords[5] = COORD(state->h) + HIGHLIGHT_WIDTH - 1;
	605	draw_polygon(fe, coords, 3, TRUE, COL_HIGHLIGHT);
	606	draw_polygon(fe, coords, 3, FALSE, COL_HIGHLIGHT);
	607
	608	coords[1] = COORD(0) - HIGHLIGHT_WIDTH;
	609	coords[0] = COORD(0) - HIGHLIGHT_WIDTH;
	610	draw_polygon(fe, coords, 3, TRUE, COL_LOWLIGHT);
	611	draw_polygon(fe, coords, 3, FALSE, COL_LOWLIGHT);
	612
	613	/*
	614	* Arrows for making moves.
	615	*/
	616	for (i = 0; i < state->w; i++) {
	617	draw_arrow(fe, COORD(i), COORD(0), +1, 0);
	618	draw_arrow(fe, COORD(i+1), COORD(state->h), -1, 0);
	619	}
	620	for (i = 0; i < state->h; i++) {
	621	draw_arrow(fe, COORD(state->w), COORD(i), 0, +1);
	622	draw_arrow(fe, COORD(0), COORD(i+1), 0, -1);
	623	}
	624
	625	ds->started = TRUE;
	626	}
	627
	628	/*
b443c381	629	* Now draw each tile.
4efb3868	630	*/
	631
	632	clip(fe, COORD(0), COORD(0), TILE_SIZEstate->w, TILE_SIZEstate->h);
	633
b443c381	634	for (i = 0; i < state->n; i++) {
	635	int t, t0;
	636	/*
	637	* Figure out what should be displayed at this
	638	* location. It's either a simple tile, or it's a
	639	* transition between two tiles (in which case we say
	640	* -1 because it must always be drawn).
	641	*/
	642
	643	if (oldstate && oldstate->tiles[i] != state->tiles[i])
	644	t = -1;
	645	else
	646	t = state->tiles[i];
	647
	648	t0 = t;
	649
	650	if (ds->bgcolour != bgcolour \|\| /* always redraw when flashing */
	651	ds->tiles[i] != t \|\| ds->tiles[i] == -1 \|\| t == -1) {
	652	int x, y, x2, y2;
	653
	654	/*
	655	* Figure out what to _actually_ draw, and where to
	656	* draw it.
	657	*/
	658	if (t == -1) {
	659	int x0, y0, x1, y1, dx, dy;
	660	int j;
	661	float c;
	662	int sense;
	663
5b5c6b12	664	if (dir < 0) {
5b5c6b12	665	assert(oldstate);
b443c381	666	sense = -oldstate->last_movement_sense;
5b5c6b12	667	} else {
b443c381	668	sense = state->last_movement_sense;
5b5c6b12	669	}
b443c381	670
	671	t = state->tiles[i];
	672
	673	/*
	674	* FIXME: must be prepared to draw a double
	675	* tile in some situations.
	676	*/
	677
	678	/*
	679	* Find the coordinates of this tile in the old and
	680	* new states.
	681	*/
	682	x1 = COORD(X(state, i));
	683	y1 = COORD(Y(state, i));
	684	for (j = 0; j < oldstate->n; j++)
	685	if (oldstate->tiles[j] == state->tiles[i])
	686	break;
	687	assert(j < oldstate->n);
	688	x0 = COORD(X(state, j));
	689	y0 = COORD(Y(state, j));
	690
	691	dx = (x1 - x0);
	692	if (dx != 0 &&
	693	dx != TILE_SIZE * sense) {
	694	dx = (dx < 0 ? dx + TILE_SIZE * state->w :
	695	dx - TILE_SIZE * state->w);
	696	assert(abs(dx) == TILE_SIZE);
	697	}
	698	dy = (y1 - y0);
	699	if (dy != 0 &&
	700	dy != TILE_SIZE * sense) {
	701	dy = (dy < 0 ? dy + TILE_SIZE * state->h :
	702	dy - TILE_SIZE * state->h);
	703	assert(abs(dy) == TILE_SIZE);
	704	}
	705
	706	c = (animtime / ANIM_TIME);
	707	if (c < 0.0F) c = 0.0F;
	708	if (c > 1.0F) c = 1.0F;
	709
	710	x = x0 + (int)(c * dx);
	711	y = y0 + (int)(c * dy);
	712	x2 = x1 - dx + (int)(c * dx);
	713	y2 = y1 - dy + (int)(c * dy);
	714	} else {
	715	x = COORD(X(state, i));
	716	y = COORD(Y(state, i));
	717	x2 = y2 = -1;
	718	}
	719
	720	draw_tile(fe, state, x, y, t, bgcolour);
	721	if (x2 != -1 \|\| y2 != -1)
	722	draw_tile(fe, state, x2, y2, t, bgcolour);
	723	}
	724	ds->tiles[i] = t0;
4efb3868	725	}
	726
	727	unclip(fe);
	728
	729	ds->bgcolour = bgcolour;
fd1a1a2b	730
	731	/*
	732	* Update the status bar.
	733	*/
	734	{
	735	char statusbuf[256];
	736
d108c342	737	/*
	738	* Don't show the new status until we're also showing the
	739	* new _state_ - after the game animation is complete.
	740	*/
	741	if (oldstate)
	742	state = oldstate;
	743
fd1a1a2b	744	sprintf(statusbuf, "%sMoves: %d",
	745	(state->completed ? "COMPLETED! " : ""),
	746	(state->completed ? state->completed : state->movecount));
	747
	748	status_bar(fe, statusbuf);
	749	}
4efb3868	750	}
4efb3868	751
be8d5aa1	752	static float game_anim_length(game_state *oldstate,
be8d5aa1	753	game_state *newstate, int dir)
4efb3868	754	{
	755	return ANIM_TIME;
	756	}
	757
be8d5aa1	758	static float game_flash_length(game_state *oldstate,
be8d5aa1	759	game_state *newstate, int dir)
4efb3868	760	{
	761	if (!oldstate->completed && newstate->completed)
	762	return 2 * FLASH_FRAME;
	763	else
	764	return 0.0F;
	765	}
fd1a1a2b	766
be8d5aa1	767	static int game_wants_statusbar(void)
fd1a1a2b	768	{
	769	return TRUE;
	770	}
be8d5aa1	771
19ef4855	772	#ifdef COMBINED
	773	#define thegame sixteen
	774	#endif
	775
be8d5aa1	776	const struct game thegame = {
	777	"Sixteen", "games.sixteen", TRUE,
	778	default_params,
	779	game_fetch_preset,
	780	decode_params,
	781	encode_params,
	782	free_params,
	783	dup_params,
	784	game_configure,
	785	custom_params,
	786	validate_params,
	787	new_game_seed,
	788	validate_seed,
	789	new_game,
	790	dup_game,
	791	free_game,
	792	new_ui,
	793	free_ui,
	794	make_move,
	795	game_size,
	796	game_colours,
	797	game_new_drawstate,
	798	game_free_drawstate,
	799	game_redraw,
	800	game_anim_length,
	801	game_flash_length,
	802	game_wants_statusbar,
	803	};