ref: e500ef963734dcf35ffa146ee917e0e0e09c325c
dir: /netslide.c/
/*
* netslide.c: cross between Net and Sixteen, courtesy of Richard
* Boulton.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <ctype.h>
#include <math.h>
#include "puzzles.h"
#include "tree234.h"
#define PI 3.141592653589793238462643383279502884197169399
#define MATMUL(xr,yr,m,x,y) do { \
float rx, ry, xx = (x), yy = (y), *mat = (m); \
rx = mat[0] * xx + mat[2] * yy; \
ry = mat[1] * xx + mat[3] * yy; \
(xr) = rx; (yr) = ry; \
} while (0)
/* Direction and other bitfields */
#define R 0x01
#define U 0x02
#define L 0x04
#define D 0x08
#define FLASHING 0x10
#define ACTIVE 0x20
/* Corner flags go in the barriers array */
#define RU 0x10
#define UL 0x20
#define LD 0x40
#define DR 0x80
/* Get tile at given coordinate */
#define T(state, x, y) ( (y) * (state)->width + (x) )
/* Rotations: Anticlockwise, Clockwise, Flip, general rotate */
#define A(x) ( (((x) & 0x07) << 1) | (((x) & 0x08) >> 3) )
#define C(x) ( (((x) & 0x0E) >> 1) | (((x) & 0x01) << 3) )
#define F(x) ( (((x) & 0x0C) >> 2) | (((x) & 0x03) << 2) )
#define ROT(x, n) ( ((n)&3) == 0 ? (x) : \
((n)&3) == 1 ? A(x) : \
((n)&3) == 2 ? F(x) : C(x) )
/* X and Y displacements */
#define X(x) ( (x) == R ? +1 : (x) == L ? -1 : 0 )
#define Y(x) ( (x) == D ? +1 : (x) == U ? -1 : 0 )
/* Bit count */
#define COUNT(x) ( (((x) & 0x08) >> 3) + (((x) & 0x04) >> 2) + \
(((x) & 0x02) >> 1) + ((x) & 0x01) )
#define TILE_SIZE 48
#define BORDER TILE_SIZE
#define TILE_BORDER 1
#define WINDOW_OFFSET 0
#define ANIM_TIME 0.13F
#define FLASH_FRAME 0.07F
enum {
COL_BACKGROUND,
COL_FLASHING,
COL_BORDER,
COL_WIRE,
COL_ENDPOINT,
COL_POWERED,
COL_BARRIER,
COL_LOWLIGHT,
COL_TEXT,
NCOLOURS
};
struct game_params {
int width;
int height;
int wrapping;
float barrier_probability;
};
struct game_state {
int width, height, cx, cy, wrapping, completed;
int move_count;
/* position (row or col number, starting at 0) of last move. */
int last_move_row, last_move_col;
/* direction of last move: +1 or -1 */
int last_move_dir;
unsigned char *tiles;
unsigned char *barriers;
};
#define OFFSET(x2,y2,x1,y1,dir,state) \
( (x2) = ((x1) + (state)->width + X((dir))) % (state)->width, \
(y2) = ((y1) + (state)->height + Y((dir))) % (state)->height)
#define index(state, a, x, y) ( a[(y) * (state)->width + (x)] )
#define tile(state, x, y) index(state, (state)->tiles, x, y)
#define barrier(state, x, y) index(state, (state)->barriers, x, y)
struct xyd {
int x, y, direction;
};
static int xyd_cmp(void *av, void *bv) {
struct xyd *a = (struct xyd *)av;
struct xyd *b = (struct xyd *)bv;
if (a->x < b->x)
return -1;
if (a->x > b->x)
return +1;
if (a->y < b->y)
return -1;
if (a->y > b->y)
return +1;
if (a->direction < b->direction)
return -1;
if (a->direction > b->direction)
return +1;
return 0;
};
static struct xyd *new_xyd(int x, int y, int direction)
{
struct xyd *xyd = snew(struct xyd);
xyd->x = x;
xyd->y = y;
xyd->direction = direction;
return xyd;
}
static void slide_col(game_state *state, int dir, int col);
static void slide_row(game_state *state, int dir, int row);
/* ----------------------------------------------------------------------
* Manage game parameters.
*/
static game_params *default_params(void)
{
game_params *ret = snew(game_params);
ret->width = 3;
ret->height = 3;
ret->wrapping = FALSE;
ret->barrier_probability = 1.0;
return ret;
}
static int game_fetch_preset(int i, char **name, game_params **params)
{
game_params *ret;
char str[80];
static const struct { int x, y, wrap, bprob; const char* desc; } values[] = {
{3, 3, FALSE, 1.0, " easy"},
{3, 3, FALSE, 0.0, " medium"},
{3, 3, TRUE, 0.0, " hard"},
{4, 4, FALSE, 1.0, " easy"},
{4, 4, FALSE, 0.0, " medium"},
{4, 4, TRUE, 0.0, " hard"},
{5, 5, FALSE, 1.0, " easy"},
{5, 5, FALSE, 0.0, " medium"},
{5, 5, TRUE, 0.0, " hard"},
};
if (i < 0 || i >= lenof(values))
return FALSE;
ret = snew(game_params);
ret->width = values[i].x;
ret->height = values[i].y;
ret->wrapping = values[i].wrap;
ret->barrier_probability = values[i].bprob;
sprintf(str, "%dx%d%s", ret->width, ret->height,
values[i].desc);
*name = dupstr(str);
*params = ret;
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();
char const *p = string;
ret->wrapping = FALSE;
ret->barrier_probability = 0.0;
ret->width = atoi(p);
while (*p && isdigit(*p)) p++;
if (*p == 'x') {
p++;
ret->height = atoi(p);
while (*p && isdigit(*p)) p++;
if ( (ret->wrapping = (*p == 'w')) != 0 )
p++;
if (*p == 'b')
ret->barrier_probability = atof(p+1);
} else {
ret->height = ret->width;
}
return ret;
}
static char *encode_params(game_params *params)
{
char ret[400];
int len;
len = sprintf(ret, "%dx%d", params->width, params->height);
if (params->wrapping)
ret[len++] = 'w';
if (params->barrier_probability)
len += sprintf(ret+len, "b%g", params->barrier_probability);
assert(len < lenof(ret));
ret[len] = '\0';
return dupstr(ret);
}
static config_item *game_configure(game_params *params)
{
config_item *ret;
char buf[80];
ret = snewn(5, config_item);
ret[0].name = "Width";
ret[0].type = C_STRING;
sprintf(buf, "%d", params->width);
ret[0].sval = dupstr(buf);
ret[0].ival = 0;
ret[1].name = "Height";
ret[1].type = C_STRING;
sprintf(buf, "%d", params->height);
ret[1].sval = dupstr(buf);
ret[1].ival = 0;
ret[2].name = "Walls wrap around";
ret[2].type = C_BOOLEAN;
ret[2].sval = NULL;
ret[2].ival = params->wrapping;
ret[3].name = "Barrier probability";
ret[3].type = C_STRING;
sprintf(buf, "%g", params->barrier_probability);
ret[3].sval = dupstr(buf);
ret[3].ival = 0;
ret[4].name = NULL;
ret[4].type = C_END;
ret[4].sval = NULL;
ret[4].ival = 0;
return ret;
}
static game_params *custom_params(config_item *cfg)
{
game_params *ret = snew(game_params);
ret->width = atoi(cfg[0].sval);
ret->height = atoi(cfg[1].sval);
ret->wrapping = cfg[2].ival;
ret->barrier_probability = (float)atof(cfg[3].sval);
return ret;
}
static char *validate_params(game_params *params)
{
if (params->width <= 1 && params->height <= 1)
return "Width and height must both be greater than one";
if (params->width <= 1)
return "Width must be greater than one";
if (params->height <= 1)
return "Height must be greater than one";
if (params->barrier_probability < 0)
return "Barrier probability may not be negative";
if (params->barrier_probability > 1)
return "Barrier probability may not be greater than 1";
return NULL;
}
/* ----------------------------------------------------------------------
* Randomly select a new game seed.
*/
static char *new_game_seed(game_params *params, random_state *rs)
{
/*
* The full description of a Net game is far too large to
* encode directly in the seed, so by default we'll have to go
* for the simple approach of providing a random-number seed.
*
* (This does not restrict me from _later on_ inventing a seed
* string syntax which can never be generated by this code -
* for example, strings beginning with a letter - allowing me
* to type in a precise game, and have new_game detect it and
* understand it and do something completely different.)
*/
char buf[40];
sprintf(buf, "%lu", random_bits(rs, 32));
return dupstr(buf);
}
static char *validate_seed(game_params *params, char *seed)
{
/*
* Since any string at all will suffice to seed the RNG, there
* is no validation required.
*/
return NULL;
}
/* ----------------------------------------------------------------------
* Construct an initial game state, given a seed and parameters.
*/
static game_state *new_game(game_params *params, char *seed)
{
random_state *rs;
game_state *state;
tree234 *possibilities, *barriers;
int w, h, x, y, nbarriers;
assert(params->width > 0 && params->height > 0);
assert(params->width > 1 || params->height > 1);
/*
* Create a blank game state.
*/
state = snew(game_state);
w = state->width = params->width;
h = state->height = params->height;
state->cx = state->width / 2;
state->cy = state->height / 2;
state->wrapping = params->wrapping;
state->completed = 0;
state->move_count = 0;
state->last_move_row = -1;
state->last_move_col = -1;
state->last_move_dir = 0;
state->tiles = snewn(state->width * state->height, unsigned char);
memset(state->tiles, 0, state->width * state->height);
state->barriers = snewn(state->width * state->height, unsigned char);
memset(state->barriers, 0, state->width * state->height);
/*
* Set up border barriers if this is a non-wrapping game.
*/
if (!state->wrapping) {
for (x = 0; x < state->width; x++) {
barrier(state, x, 0) |= U;
barrier(state, x, state->height-1) |= D;
}
for (y = 0; y < state->height; y++) {
barrier(state, 0, y) |= L;
barrier(state, state->width-1, y) |= R;
}
}
/*
* Seed the internal random number generator.
*/
rs = random_init(seed, strlen(seed));
/*
* Construct the unshuffled grid.
*
* To do this, we simply start at the centre point, repeatedly
* choose a random possibility out of the available ways to
* extend a used square into an unused one, and do it. After
* extending the third line out of a square, we remove the
* fourth from the possibilities list to avoid any full-cross
* squares (which would make the game too easy because they
* only have one orientation).
*
* The slightly worrying thing is the avoidance of full-cross
* squares. Can this cause our unsophisticated construction
* algorithm to paint itself into a corner, by getting into a
* situation where there are some unreached squares and the
* only way to reach any of them is to extend a T-piece into a
* full cross?
*
* Answer: no it can't, and here's a proof.
*
* Any contiguous group of such unreachable squares must be
* surrounded on _all_ sides by T-pieces pointing away from the
* group. (If not, then there is a square which can be extended
* into one of the `unreachable' ones, and so it wasn't
* unreachable after all.) In particular, this implies that
* each contiguous group of unreachable squares must be
* rectangular in shape (any deviation from that yields a
* non-T-piece next to an `unreachable' square).
*
* So we have a rectangle of unreachable squares, with T-pieces
* forming a solid border around the rectangle. The corners of
* that border must be connected (since every tile connects all
* the lines arriving in it), and therefore the border must
* form a closed loop around the rectangle.
*
* But this can't have happened in the first place, since we
* _know_ we've avoided creating closed loops! Hence, no such
* situation can ever arise, and the naive grid construction
* algorithm will guaranteeably result in a complete grid
* containing no unreached squares, no full crosses _and_ no
* closed loops. []
*/
possibilities = newtree234(xyd_cmp);
if (state->cx+1 < state->width)
add234(possibilities, new_xyd(state->cx, state->cy, R));
if (state->cy-1 >= 0)
add234(possibilities, new_xyd(state->cx, state->cy, U));
if (state->cx-1 >= 0)
add234(possibilities, new_xyd(state->cx, state->cy, L));
if (state->cy+1 < state->height)
add234(possibilities, new_xyd(state->cx, state->cy, D));
while (count234(possibilities) > 0) {
int i;
struct xyd *xyd;
int x1, y1, d1, x2, y2, d2, d;
/*
* Extract a randomly chosen possibility from the list.
*/
i = random_upto(rs, count234(possibilities));
xyd = delpos234(possibilities, i);
x1 = xyd->x;
y1 = xyd->y;
d1 = xyd->direction;
sfree(xyd);
OFFSET(x2, y2, x1, y1, d1, state);
d2 = F(d1);
#ifdef DEBUG
printf("picked (%d,%d,%c) <-> (%d,%d,%c)\n",
x1, y1, "0RU3L567D9abcdef"[d1], x2, y2, "0RU3L567D9abcdef"[d2]);
#endif
/*
* Make the connection. (We should be moving to an as yet
* unused tile.)
*/
tile(state, x1, y1) |= d1;
assert(tile(state, x2, y2) == 0);
tile(state, x2, y2) |= d2;
/*
* If we have created a T-piece, remove its last
* possibility.
*/
if (COUNT(tile(state, x1, y1)) == 3) {
struct xyd xyd1, *xydp;
xyd1.x = x1;
xyd1.y = y1;
xyd1.direction = 0x0F ^ tile(state, x1, y1);
xydp = find234(possibilities, &xyd1, NULL);
if (xydp) {
#ifdef DEBUG
printf("T-piece; removing (%d,%d,%c)\n",
xydp->x, xydp->y, "0RU3L567D9abcdef"[xydp->direction]);
#endif
del234(possibilities, xydp);
sfree(xydp);
}
}
/*
* Remove all other possibilities that were pointing at the
* tile we've just moved into.
*/
for (d = 1; d < 0x10; d <<= 1) {
int x3, y3, d3;
struct xyd xyd1, *xydp;
OFFSET(x3, y3, x2, y2, d, state);
d3 = F(d);
xyd1.x = x3;
xyd1.y = y3;
xyd1.direction = d3;
xydp = find234(possibilities, &xyd1, NULL);
if (xydp) {
#ifdef DEBUG
printf("Loop avoidance; removing (%d,%d,%c)\n",
xydp->x, xydp->y, "0RU3L567D9abcdef"[xydp->direction]);
#endif
del234(possibilities, xydp);
sfree(xydp);
}
}
/*
* Add new possibilities to the list for moving _out_ of
* the tile we have just moved into.
*/
for (d = 1; d < 0x10; d <<= 1) {
int x3, y3;
if (d == d2)
continue; /* we've got this one already */
if (!state->wrapping) {
if (d == U && y2 == 0)
continue;
if (d == D && y2 == state->height-1)
continue;
if (d == L && x2 == 0)
continue;
if (d == R && x2 == state->width-1)
continue;
}
OFFSET(x3, y3, x2, y2, d, state);
if (tile(state, x3, y3))
continue; /* this would create a loop */
#ifdef DEBUG
printf("New frontier; adding (%d,%d,%c)\n",
x2, y2, "0RU3L567D9abcdef"[d]);
#endif
add234(possibilities, new_xyd(x2, y2, d));
}
}
/* Having done that, we should have no possibilities remaining. */
assert(count234(possibilities) == 0);
freetree234(possibilities);
/*
* Now compute a list of the possible barrier locations.
*/
barriers = newtree234(xyd_cmp);
for (y = 0; y < state->height; y++) {
for (x = 0; x < state->width; x++) {
if (!(tile(state, x, y) & R) &&
(state->wrapping || x < state->width-1))
add234(barriers, new_xyd(x, y, R));
if (!(tile(state, x, y) & D) &&
(state->wrapping || y < state->height-1))
add234(barriers, new_xyd(x, y, D));
}
}
/*
* Now shuffle the grid.
* FIXME - this simply does a set of random moves to shuffle the pieces.
* A better way would be to number all the pieces, generate a placement
* for all the numbers as for "sixteen", observing parity constraints if
* neccessary, and then place the pieces according to their numbering.
* BUT - I'm not sure if this will work, since we disallow movement of
* the middle row and column.
*/
{
int i;
int cols = state->width - 1;
int rows = state->height - 1;
for (i = 0; i < cols * rows * 2; i++) {
/* Choose a direction: 0,1,2,3 = up, right, down, left. */
int dir = random_upto(rs, 4);
if (dir % 2 == 0) {
int col = random_upto(rs, cols);
if (col >= state->cx) col += 1;
slide_col(state, 1 - dir, col);
} else {
int row = random_upto(rs, rows);
if (row >= state->cy) row += 1;
slide_row(state, 2 - dir, row);
}
}
}
/*
* And now choose barrier locations. (We carefully do this
* _after_ shuffling, so that changing the barrier rate in the
* params while keeping the game seed the same will give the
* same shuffled grid and _only_ change the barrier locations.
* Also the way we choose barrier locations, by repeatedly
* choosing one possibility from the list until we have enough,
* is designed to ensure that raising the barrier rate while
* keeping the seed the same will provide a superset of the
* previous barrier set - i.e. if you ask for 10 barriers, and
* then decide that's still too hard and ask for 20, you'll get
* the original 10 plus 10 more, rather than getting 20 new
* ones and the chance of remembering your first 10.)
*/
nbarriers = (int)(params->barrier_probability * count234(barriers));
assert(nbarriers >= 0 && nbarriers <= count234(barriers));
while (nbarriers > 0) {
int i;
struct xyd *xyd;
int x1, y1, d1, x2, y2, d2;
/*
* Extract a randomly chosen barrier from the list.
*/
i = random_upto(rs, count234(barriers));
xyd = delpos234(barriers, i);
assert(xyd != NULL);
x1 = xyd->x;
y1 = xyd->y;
d1 = xyd->direction;
sfree(xyd);
OFFSET(x2, y2, x1, y1, d1, state);
d2 = F(d1);
barrier(state, x1, y1) |= d1;
barrier(state, x2, y2) |= d2;
nbarriers--;
}
/*
* Clean up the rest of the barrier list.
*/
{
struct xyd *xyd;
while ( (xyd = delpos234(barriers, 0)) != NULL)
sfree(xyd);
freetree234(barriers);
}
/*
* Set up the barrier corner flags, for drawing barriers
* prettily when they meet.
*/
for (y = 0; y < state->height; y++) {
for (x = 0; x < state->width; x++) {
int dir;
for (dir = 1; dir < 0x10; dir <<= 1) {
int dir2 = A(dir);
int x1, y1, x2, y2, x3, y3;
int corner = FALSE;
if (!(barrier(state, x, y) & dir))
continue;
if (barrier(state, x, y) & dir2)
corner = TRUE;
x1 = x + X(dir), y1 = y + Y(dir);
if (x1 >= 0 && x1 < state->width &&
y1 >= 0 && y1 < state->height &&
(barrier(state, x1, y1) & dir2))
corner = TRUE;
x2 = x + X(dir2), y2 = y + Y(dir2);
if (x2 >= 0 && x2 < state->width &&
y2 >= 0 && y2 < state->height &&
(barrier(state, x2, y2) & dir))
corner = TRUE;
if (corner) {
barrier(state, x, y) |= (dir << 4);
if (x1 >= 0 && x1 < state->width &&
y1 >= 0 && y1 < state->height)
barrier(state, x1, y1) |= (A(dir) << 4);
if (x2 >= 0 && x2 < state->width &&
y2 >= 0 && y2 < state->height)
barrier(state, x2, y2) |= (C(dir) << 4);
x3 = x + X(dir) + X(dir2), y3 = y + Y(dir) + Y(dir2);
if (x3 >= 0 && x3 < state->width &&
y3 >= 0 && y3 < state->height)
barrier(state, x3, y3) |= (F(dir) << 4);
}
}
}
}
random_free(rs);
return state;
}
static game_state *dup_game(game_state *state)
{
game_state *ret;
ret = snew(game_state);
ret->width = state->width;
ret->height = state->height;
ret->cx = state->cx;
ret->cy = state->cy;
ret->wrapping = state->wrapping;
ret->completed = state->completed;
ret->move_count = state->move_count;
ret->last_move_row = state->last_move_row;
ret->last_move_col = state->last_move_col;
ret->last_move_dir = state->last_move_dir;
ret->tiles = snewn(state->width * state->height, unsigned char);
memcpy(ret->tiles, state->tiles, state->width * state->height);
ret->barriers = snewn(state->width * state->height, unsigned char);
memcpy(ret->barriers, state->barriers, state->width * state->height);
return ret;
}
static void free_game(game_state *state)
{
sfree(state->tiles);
sfree(state->barriers);
sfree(state);
}
/* ----------------------------------------------------------------------
* Utility routine.
*/
/*
* Compute which squares are reachable from the centre square, as a
* quick visual aid to determining how close the game is to
* completion. This is also a simple way to tell if the game _is_
* completed - just call this function and see whether every square
* is marked active.
*
* squares in the moving_row and moving_col are always inactive - this
* is so that "current" doesn't appear to jump across moving lines.
*/
static unsigned char *compute_active(game_state *state,
int moving_row, int moving_col)
{
unsigned char *active;
tree234 *todo;
struct xyd *xyd;
active = snewn(state->width * state->height, unsigned char);
memset(active, 0, state->width * state->height);
/*
* We only store (x,y) pairs in todo, but it's easier to reuse
* xyd_cmp and just store direction 0 every time.
*/
todo = newtree234(xyd_cmp);
index(state, active, state->cx, state->cy) = ACTIVE;
add234(todo, new_xyd(state->cx, state->cy, 0));
while ( (xyd = delpos234(todo, 0)) != NULL) {
int x1, y1, d1, x2, y2, d2;
x1 = xyd->x;
y1 = xyd->y;
sfree(xyd);
for (d1 = 1; d1 < 0x10; d1 <<= 1) {
OFFSET(x2, y2, x1, y1, d1, state);
d2 = F(d1);
/*
* If the next tile in this direction is connected to
* us, and there isn't a barrier in the way, and it
* isn't already marked active, then mark it active and
* add it to the to-examine list.
*/
if ((x2 != moving_col && y2 != moving_row) &&
(tile(state, x1, y1) & d1) &&
(tile(state, x2, y2) & d2) &&
!(barrier(state, x1, y1) & d1) &&
!index(state, active, x2, y2)) {
index(state, active, x2, y2) = ACTIVE;
add234(todo, new_xyd(x2, y2, 0));
}
}
}
/* Now we expect the todo list to have shrunk to zero size. */
assert(count234(todo) == 0);
freetree234(todo);
return active;
}
struct game_ui {
int cur_x, cur_y;
int cur_visible;
};
static game_ui *new_ui(game_state *state)
{
game_ui *ui = snew(game_ui);
ui->cur_x = state->width / 2;
ui->cur_y = state->height / 2;
ui->cur_visible = FALSE;
return ui;
}
static void free_ui(game_ui *ui)
{
sfree(ui);
}
/* ----------------------------------------------------------------------
* Process a move.
*/
static void slide_row(game_state *state, int dir, int row)
{
int x = dir > 0 ? -1 : state->width;
int tx = x + dir;
int n = state->width - 1;
unsigned char endtile = state->tiles[T(state, tx, row)];
do {
x = tx;
tx = (x + dir + state->width) % state->width;
state->tiles[T(state, x, row)] = state->tiles[T(state, tx, row)];
} while (--n > 0);
state->tiles[T(state, tx, row)] = endtile;
}
static void slide_col(game_state *state, int dir, int col)
{
int y = dir > 0 ? -1 : state->height;
int ty = y + dir;
int n = state->height - 1;
unsigned char endtile = state->tiles[T(state, col, ty)];
do {
y = ty;
ty = (y + dir + state->height) % state->height;
state->tiles[T(state, col, y)] = state->tiles[T(state, col, ty)];
} while (--n > 0);
state->tiles[T(state, col, ty)] = endtile;
}
static game_state *make_move(game_state *state, game_ui *ui,
int x, int y, int button)
{
int cx, cy;
int n, dx, dy;
game_state *ret;
if (button != LEFT_BUTTON && button != RIGHT_BUTTON)
return NULL;
cx = (x - (BORDER + WINDOW_OFFSET + TILE_BORDER) + 2*TILE_SIZE) / TILE_SIZE - 2;
cy = (y - (BORDER + WINDOW_OFFSET + TILE_BORDER) + 2*TILE_SIZE) / TILE_SIZE - 2;
if (cy >= 0 && cy < state->height && cy != state->cy)
{
if (cx == -1) dx = +1;
else if (cx == state->width) dx = -1;
else return NULL;
n = state->width;
dy = 0;
}
else if (cx >= 0 && cx < state->width && cx != state->cx)
{
if (cy == -1) dy = +1;
else if (cy == state->height) dy = -1;
else return NULL;
n = state->height;
dx = 0;
}
else
return NULL;
/* reverse direction if right hand button is pressed */
if (button == RIGHT_BUTTON)
{
dx = -dx;
dy = -dy;
}
ret = dup_game(state);
if (dx == 0) slide_col(ret, dy, cx);
else slide_row(ret, dx, cy);
ret->move_count++;
ret->last_move_row = dx ? cy : -1;
ret->last_move_col = dx ? -1 : cx;
ret->last_move_dir = dx + dy;
/*
* See if the game has been completed.
*/
if (!ret->completed) {
unsigned char *active = compute_active(ret, -1, -1);
int x1, y1;
int complete = TRUE;
for (x1 = 0; x1 < ret->width; x1++)
for (y1 = 0; y1 < ret->height; y1++)
if (!index(ret, active, x1, y1)) {
complete = FALSE;
goto break_label; /* break out of two loops at once */
}
break_label:
sfree(active);
if (complete)
ret->completed = ret->move_count;
}
return ret;
}
/* ----------------------------------------------------------------------
* Routines for drawing the game position on the screen.
*/
struct game_drawstate {
int started;
int width, height;
unsigned char *visible;
};
static game_drawstate *game_new_drawstate(game_state *state)
{
game_drawstate *ds = snew(game_drawstate);
ds->started = FALSE;
ds->width = state->width;
ds->height = state->height;
ds->visible = snewn(state->width * state->height, unsigned char);
memset(ds->visible, 0xFF, state->width * state->height);
return ds;
}
static void game_free_drawstate(game_drawstate *ds)
{
sfree(ds->visible);
sfree(ds);
}
static void game_size(game_params *params, int *x, int *y)
{
*x = BORDER * 2 + WINDOW_OFFSET * 2 + TILE_SIZE * params->width + TILE_BORDER;
*y = BORDER * 2 + WINDOW_OFFSET * 2 + TILE_SIZE * params->height + TILE_BORDER;
}
static float *game_colours(frontend *fe, game_state *state, int *ncolours)
{
float *ret;
ret = snewn(NCOLOURS * 3, float);
*ncolours = NCOLOURS;
/*
* Basic background colour is whatever the front end thinks is
* a sensible default.
*/
frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
/*
* Wires are black.
*/
ret[COL_WIRE * 3 + 0] = 0.0F;
ret[COL_WIRE * 3 + 1] = 0.0F;
ret[COL_WIRE * 3 + 2] = 0.0F;
/*
* Powered wires and powered endpoints are cyan.
*/
ret[COL_POWERED * 3 + 0] = 0.0F;
ret[COL_POWERED * 3 + 1] = 1.0F;
ret[COL_POWERED * 3 + 2] = 1.0F;
/*
* Barriers are red.
*/
ret[COL_BARRIER * 3 + 0] = 1.0F;
ret[COL_BARRIER * 3 + 1] = 0.0F;
ret[COL_BARRIER * 3 + 2] = 0.0F;
/*
* Unpowered endpoints are blue.
*/
ret[COL_ENDPOINT * 3 + 0] = 0.0F;
ret[COL_ENDPOINT * 3 + 1] = 0.0F;
ret[COL_ENDPOINT * 3 + 2] = 1.0F;
/*
* Tile borders are a darker grey than the background.
*/
ret[COL_BORDER * 3 + 0] = 0.5F * ret[COL_BACKGROUND * 3 + 0];
ret[COL_BORDER * 3 + 1] = 0.5F * ret[COL_BACKGROUND * 3 + 1];
ret[COL_BORDER * 3 + 2] = 0.5F * ret[COL_BACKGROUND * 3 + 2];
/*
* Flashing tiles are a grey in between those two.
*/
ret[COL_FLASHING * 3 + 0] = 0.75F * ret[COL_BACKGROUND * 3 + 0];
ret[COL_FLASHING * 3 + 1] = 0.75F * ret[COL_BACKGROUND * 3 + 1];
ret[COL_FLASHING * 3 + 2] = 0.75F * ret[COL_BACKGROUND * 3 + 2];
ret[COL_LOWLIGHT * 3 + 0] = ret[COL_BACKGROUND * 3 + 0] * 0.8F;
ret[COL_LOWLIGHT * 3 + 1] = ret[COL_BACKGROUND * 3 + 1] * 0.8F;
ret[COL_LOWLIGHT * 3 + 2] = ret[COL_BACKGROUND * 3 + 2] * 0.8F;
ret[COL_TEXT * 3 + 0] = 0.0;
ret[COL_TEXT * 3 + 1] = 0.0;
ret[COL_TEXT * 3 + 2] = 0.0;
return ret;
}
static void draw_thick_line(frontend *fe, int x1, int y1, int x2, int y2,
int colour)
{
draw_line(fe, x1-1, y1, x2-1, y2, COL_WIRE);
draw_line(fe, x1+1, y1, x2+1, y2, COL_WIRE);
draw_line(fe, x1, y1-1, x2, y2-1, COL_WIRE);
draw_line(fe, x1, y1+1, x2, y2+1, COL_WIRE);
draw_line(fe, x1, y1, x2, y2, colour);
}
static void draw_rect_coords(frontend *fe, int x1, int y1, int x2, int y2,
int colour)
{
int mx = (x1 < x2 ? x1 : x2);
int my = (y1 < y2 ? y1 : y2);
int dx = (x2 + x1 - 2*mx + 1);
int dy = (y2 + y1 - 2*my + 1);
draw_rect(fe, mx, my, dx, dy, colour);
}
static void draw_barrier_corner(frontend *fe, int x, int y, int dir, int phase)
{
int bx = BORDER + WINDOW_OFFSET + TILE_SIZE * x;
int by = BORDER + WINDOW_OFFSET + TILE_SIZE * y;
int x1, y1, dx, dy, dir2;
dir >>= 4;
dir2 = A(dir);
dx = X(dir) + X(dir2);
dy = Y(dir) + Y(dir2);
x1 = (dx > 0 ? TILE_SIZE+TILE_BORDER-1 : 0);
y1 = (dy > 0 ? TILE_SIZE+TILE_BORDER-1 : 0);
if (phase == 0) {
draw_rect_coords(fe, bx+x1, by+y1,
bx+x1-TILE_BORDER*dx, by+y1-(TILE_BORDER-1)*dy,
COL_WIRE);
draw_rect_coords(fe, bx+x1, by+y1,
bx+x1-(TILE_BORDER-1)*dx, by+y1-TILE_BORDER*dy,
COL_WIRE);
} else {
draw_rect_coords(fe, bx+x1, by+y1,
bx+x1-(TILE_BORDER-1)*dx, by+y1-(TILE_BORDER-1)*dy,
COL_BARRIER);
}
}
static void draw_barrier(frontend *fe, int x, int y, int dir, int phase)
{
int bx = BORDER + WINDOW_OFFSET + TILE_SIZE * x;
int by = BORDER + WINDOW_OFFSET + TILE_SIZE * y;
int x1, y1, w, h;
x1 = (X(dir) > 0 ? TILE_SIZE : X(dir) == 0 ? TILE_BORDER : 0);
y1 = (Y(dir) > 0 ? TILE_SIZE : Y(dir) == 0 ? TILE_BORDER : 0);
w = (X(dir) ? TILE_BORDER : TILE_SIZE - TILE_BORDER);
h = (Y(dir) ? TILE_BORDER : TILE_SIZE - TILE_BORDER);
if (phase == 0) {
draw_rect(fe, bx+x1-X(dir), by+y1-Y(dir), w, h, COL_WIRE);
} else {
draw_rect(fe, bx+x1, by+y1, w, h, COL_BARRIER);
}
}
static void draw_tile(frontend *fe, game_state *state, int x, int y, int tile,
float xshift, float yshift)
{
int bx = BORDER + WINDOW_OFFSET + TILE_SIZE * x + (xshift * TILE_SIZE);
int by = BORDER + WINDOW_OFFSET + TILE_SIZE * y + (yshift * TILE_SIZE);
float cx, cy, ex, ey;
int dir, col;
/*
* When we draw a single tile, we must draw everything up to
* and including the borders around the tile. This means that
* if the neighbouring tiles have connections to those borders,
* we must draw those connections on the borders themselves.
*
* This would be terribly fiddly if we ever had to draw a tile
* while its neighbour was in mid-rotate, because we'd have to
* arrange to _know_ that the neighbour was being rotated and
* hence had an anomalous effect on the redraw of this tile.
* Fortunately, the drawing algorithm avoids ever calling us in
* this circumstance: we're either drawing lots of straight
* tiles at game start or after a move is complete, or we're
* repeatedly drawing only the rotating tile. So no problem.
*/
/*
* So. First blank the tile out completely: draw a big
* rectangle in border colour, and a smaller rectangle in
* background colour to fill it in.
*/
draw_rect(fe, bx, by, TILE_SIZE+TILE_BORDER, TILE_SIZE+TILE_BORDER,
COL_BORDER);
draw_rect(fe, bx+TILE_BORDER, by+TILE_BORDER,
TILE_SIZE-TILE_BORDER, TILE_SIZE-TILE_BORDER,
tile & FLASHING ? COL_FLASHING : COL_BACKGROUND);
/*
* Draw the wires.
*/
cx = cy = TILE_BORDER + (TILE_SIZE-TILE_BORDER) / 2.0F - 0.5F;
col = (tile & ACTIVE ? COL_POWERED : COL_WIRE);
for (dir = 1; dir < 0x10; dir <<= 1) {
if (tile & dir) {
ex = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * X(dir);
ey = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * Y(dir);
draw_thick_line(fe, bx+(int)cx, by+(int)cy,
bx+(int)(cx+ex), by+(int)(cy+ey),
COL_WIRE);
}
}
for (dir = 1; dir < 0x10; dir <<= 1) {
if (tile & dir) {
ex = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * X(dir);
ey = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * Y(dir);
draw_line(fe, bx+(int)cx, by+(int)cy,
bx+(int)(cx+ex), by+(int)(cy+ey), col);
}
}
/*
* Draw the box in the middle. We do this in blue if the tile
* is an unpowered endpoint, in cyan if the tile is a powered
* endpoint, in black if the tile is the centrepiece, and
* otherwise not at all.
*/
col = -1;
if (x == state->cx && y == state->cy)
col = COL_WIRE;
else if (COUNT(tile) == 1) {
col = (tile & ACTIVE ? COL_POWERED : COL_ENDPOINT);
}
if (col >= 0) {
int i, points[8];
points[0] = +1; points[1] = +1;
points[2] = +1; points[3] = -1;
points[4] = -1; points[5] = -1;
points[6] = -1; points[7] = +1;
for (i = 0; i < 8; i += 2) {
ex = (TILE_SIZE * 0.24F) * points[i];
ey = (TILE_SIZE * 0.24F) * points[i+1];
points[i] = bx+(int)(cx+ex);
points[i+1] = by+(int)(cy+ey);
}
draw_polygon(fe, points, 4, TRUE, col);
draw_polygon(fe, points, 4, FALSE, COL_WIRE);
}
/*
* Draw the points on the border if other tiles are connected
* to us.
*/
for (dir = 1; dir < 0x10; dir <<= 1) {
int dx, dy, px, py, lx, ly, vx, vy, ox, oy;
dx = X(dir);
dy = Y(dir);
ox = x + dx;
oy = y + dy;
if (ox < 0 || ox >= state->width || oy < 0 || oy >= state->height)
continue;
if (!(tile(state, ox, oy) & F(dir)))
continue;
px = bx + (int)(dx>0 ? TILE_SIZE + TILE_BORDER - 1 : dx<0 ? 0 : cx);
py = by + (int)(dy>0 ? TILE_SIZE + TILE_BORDER - 1 : dy<0 ? 0 : cy);
lx = dx * (TILE_BORDER-1);
ly = dy * (TILE_BORDER-1);
vx = (dy ? 1 : 0);
vy = (dx ? 1 : 0);
if (xshift == 0.0 && yshift == 0.0 && (tile & dir)) {
/*
* If we are fully connected to the other tile, we must
* draw right across the tile border. (We can use our
* own ACTIVE state to determine what colour to do this
* in: if we are fully connected to the other tile then
* the two ACTIVE states will be the same.)
*/
draw_rect_coords(fe, px-vx, py-vy, px+lx+vx, py+ly+vy, COL_WIRE);
draw_rect_coords(fe, px, py, px+lx, py+ly,
(tile & ACTIVE) ? COL_POWERED : COL_WIRE);
} else {
/*
* The other tile extends into our border, but isn't
* actually connected to us. Just draw a single black
* dot.
*/
draw_rect_coords(fe, px, py, px, py, COL_WIRE);
}
}
draw_update(fe, bx, by, TILE_SIZE+TILE_BORDER, TILE_SIZE+TILE_BORDER);
}
static void draw_tile_barriers(frontend *fe, game_state *state, int x, int y)
{
int phase;
int dir;
int bx = BORDER + WINDOW_OFFSET + TILE_SIZE * x;
int by = BORDER + WINDOW_OFFSET + TILE_SIZE * y;
/*
* Draw barrier corners, and then barriers.
*/
for (phase = 0; phase < 2; phase++) {
for (dir = 1; dir < 0x10; dir <<= 1)
if (barrier(state, x, y) & (dir << 4))
draw_barrier_corner(fe, x, y, dir << 4, phase);
for (dir = 1; dir < 0x10; dir <<= 1)
if (barrier(state, x, y) & dir)
draw_barrier(fe, x, y, dir, phase);
}
draw_update(fe, bx, by, TILE_SIZE+TILE_BORDER, TILE_SIZE+TILE_BORDER);
}
static void draw_arrow(frontend *fe, int x, int y, int xdx, int xdy)
{
int coords[14];
int ydy = -xdx, ydx = xdy;
x = x * TILE_SIZE + BORDER + WINDOW_OFFSET;
y = y * TILE_SIZE + BORDER + WINDOW_OFFSET;
#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 t, float ft)
{
int x, y, tx, ty, frame;
unsigned char *active;
float xshift = 0.0;
float yshift = 0.0;
/*
* Clear the screen and draw the exterior barrier lines if this
* is our first call.
*/
if (!ds->started) {
int phase;
ds->started = TRUE;
draw_rect(fe, 0, 0,
BORDER * 2 + WINDOW_OFFSET * 2 + TILE_SIZE * state->width + TILE_BORDER,
BORDER * 2 + WINDOW_OFFSET * 2 + TILE_SIZE * state->height + TILE_BORDER,
COL_BACKGROUND);
draw_update(fe, 0, 0,
BORDER * 2 + WINDOW_OFFSET*2 + TILE_SIZE*state->width + TILE_BORDER,
BORDER * 2 + WINDOW_OFFSET*2 + TILE_SIZE*state->height + TILE_BORDER);
for (phase = 0; phase < 2; phase++) {
for (x = 0; x < ds->width; x++) {
if (barrier(state, x, 0) & UL)
draw_barrier_corner(fe, x, -1, LD, phase);
if (barrier(state, x, 0) & RU)
draw_barrier_corner(fe, x, -1, DR, phase);
if (barrier(state, x, 0) & U)
draw_barrier(fe, x, -1, D, phase);
if (barrier(state, x, ds->height-1) & DR)
draw_barrier_corner(fe, x, ds->height, RU, phase);
if (barrier(state, x, ds->height-1) & LD)
draw_barrier_corner(fe, x, ds->height, UL, phase);
if (barrier(state, x, ds->height-1) & D)
draw_barrier(fe, x, ds->height, U, phase);
}
for (y = 0; y < ds->height; y++) {
if (barrier(state, 0, y) & UL)
draw_barrier_corner(fe, -1, y, RU, phase);
if (barrier(state, 0, y) & LD)
draw_barrier_corner(fe, -1, y, DR, phase);
if (barrier(state, 0, y) & L)
draw_barrier(fe, -1, y, R, phase);
if (barrier(state, ds->width-1, y) & RU)
draw_barrier_corner(fe, ds->width, y, UL, phase);
if (barrier(state, ds->width-1, y) & DR)
draw_barrier_corner(fe, ds->width, y, LD, phase);
if (barrier(state, ds->width-1, y) & R)
draw_barrier(fe, ds->width, y, L, phase);
}
}
/*
* Arrows for making moves.
*/
for (x = 0; x < ds->width; x++) {
if (x == state->cx) continue;
draw_arrow(fe, x, 0, +1, 0);
draw_arrow(fe, x+1, ds->height, -1, 0);
}
for (y = 0; y < ds->height; y++) {
if (y == state->cy) continue;
draw_arrow(fe, ds->width, y, 0, +1);
draw_arrow(fe, 0, y+1, 0, -1);
}
}
/* Check if this is an undo. If so, we will need to run any animation
* backwards.
*/
if (oldstate && oldstate->move_count > state->move_count) {
game_state * tmpstate = state;
state = oldstate;
oldstate = tmpstate;
t = ANIM_TIME - t;
}
tx = ty = -1;
if (oldstate && (t < ANIM_TIME)) {
/*
* We're animating a slide, of row/column number
* state->last_move_pos, in direction
* state->last_move_dir
*/
xshift = state->last_move_row == -1 ? 0.0 :
(1 - t / ANIM_TIME) * state->last_move_dir;
yshift = state->last_move_col == -1 ? 0.0 :
(1 - t / ANIM_TIME) * state->last_move_dir;
}
frame = -1;
if (ft > 0) {
/*
* We're animating a completion flash. Find which frame
* we're at.
*/
frame = (int)(ft / FLASH_FRAME);
}
/*
* Draw any tile which differs from the way it was last drawn.
*/
if (xshift != 0.0 || yshift != 0.0) {
active = compute_active(state,
state->last_move_row, state->last_move_col);
} else {
active = compute_active(state, -1, -1);
}
clip(fe,
BORDER + WINDOW_OFFSET, BORDER + WINDOW_OFFSET,
TILE_SIZE * state->width + TILE_BORDER,
TILE_SIZE * state->height + TILE_BORDER);
for (x = 0; x < ds->width; x++)
for (y = 0; y < ds->height; y++) {
unsigned char c = tile(state, x, y) | index(state, active, x, y);
/*
* In a completion flash, we adjust the FLASHING bit
* depending on our distance from the centre point and
* the frame number.
*/
if (frame >= 0) {
int xdist, ydist, dist;
xdist = (x < state->cx ? state->cx - x : x - state->cx);
ydist = (y < state->cy ? state->cy - y : y - state->cy);
dist = (xdist > ydist ? xdist : ydist);
if (frame >= dist && frame < dist+4) {
int flash = (frame - dist) & 1;
flash = flash ? FLASHING : 0;
c = (c &~ FLASHING) | flash;
}
}
if (index(state, ds->visible, x, y) != c ||
index(state, ds->visible, x, y) == 0xFF ||
(x == state->last_move_col || y == state->last_move_row))
{
float xs = (y == state->last_move_row ? xshift : 0.0);
float ys = (x == state->last_move_col ? yshift : 0.0);
draw_tile(fe, state, x, y, c, xs, ys);
if (xs < 0 && x == 0)
draw_tile(fe, state, state->width, y, c, xs, ys);
else if (xs > 0 && x == state->width - 1)
draw_tile(fe, state, -1, y, c, xs, ys);
else if (ys < 0 && y == 0)
draw_tile(fe, state, x, state->height, c, xs, ys);
else if (ys > 0 && y == state->height - 1)
draw_tile(fe, state, x, -1, c, xs, ys);
if (x == state->last_move_col || y == state->last_move_row)
index(state, ds->visible, x, y) = 0xFF;
else
index(state, ds->visible, x, y) = c;
}
}
for (x = 0; x < ds->width; x++)
for (y = 0; y < ds->height; y++)
draw_tile_barriers(fe, state, x, y);
unclip(fe);
/*
* Update the status bar.
*/
{
char statusbuf[256];
int i, n, a;
n = state->width * state->height;
for (i = a = 0; i < n; i++)
if (active[i])
a++;
sprintf(statusbuf, "%sMoves: %d Active: %d/%d",
(state->completed ? "COMPLETED! " : ""),
(state->completed ? state->completed : state->move_count),
a, n);
status_bar(fe, statusbuf);
}
sfree(active);
}
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 the game has just been completed, we display a completion
* flash.
*/
if (!oldstate->completed && newstate->completed) {
int size;
size = 0;
if (size < newstate->cx+1)
size = newstate->cx+1;
if (size < newstate->cy+1)
size = newstate->cy+1;
if (size < newstate->width - newstate->cx)
size = newstate->width - newstate->cx;
if (size < newstate->height - newstate->cy)
size = newstate->height - newstate->cy;
return FLASH_FRAME * (size+4);
}
return 0.0F;
}
static int game_wants_statusbar(void)
{
return TRUE;
}
#ifdef COMBINED
#define thegame netslide
#endif
const struct game thegame = {
"Netslide", "games.netslide", 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,
};