14 const char *const game_name = "Net";
15 const int game_can_configure = TRUE;
17 #define PI 3.141592653589793238462643383279502884197169399
19 #define MATMUL(xr,yr,m,x,y) do { \
20 float rx, ry, xx = (x), yy = (y), *mat = (m); \
21 rx = mat[0] * xx + mat[2] * yy; \
22 ry = mat[1] * xx + mat[3] * yy; \
23 (xr) = rx; (yr) = ry; \
26 /* Direction and other bitfields */
33 /* Corner flags go in the barriers array */
39 /* Rotations: Anticlockwise, Clockwise, Flip, general rotate */
40 #define A(x) ( (((x) & 0x07) << 1) | (((x) & 0x08) >> 3) )
41 #define C(x) ( (((x) & 0x0E) >> 1) | (((x) & 0x01) << 3) )
42 #define F(x) ( (((x) & 0x0C) >> 2) | (((x) & 0x03) << 2) )
43 #define ROT(x, n) ( ((n)&3) == 0 ? (x) : \
44 ((n)&3) == 1 ? A(x) : \
45 ((n)&3) == 2 ? F(x) : C(x) )
47 /* X and Y displacements */
48 #define X(x) ( (x) == R ? +1 : (x) == L ? -1 : 0 )
49 #define Y(x) ( (x) == D ? +1 : (x) == U ? -1 : 0 )
52 #define COUNT(x) ( (((x) & 0x08) >> 3) + (((x) & 0x04) >> 2) + \
53 (((x) & 0x02) >> 1) + ((x) & 0x01) )
57 #define WINDOW_OFFSET 16
59 #define ROTATE_TIME 0.1F
60 #define FLASH_FRAME 0.05F
77 float barrier_probability;
81 int width, height, cx, cy, wrapping, completed, last_rotate_dir;
83 unsigned char *barriers;
86 #define OFFSET(x2,y2,x1,y1,dir,state) \
87 ( (x2) = ((x1) + (state)->width + X((dir))) % (state)->width, \
88 (y2) = ((y1) + (state)->height + Y((dir))) % (state)->height)
90 #define index(state, a, x, y) ( a[(y) * (state)->width + (x)] )
91 #define tile(state, x, y) index(state, (state)->tiles, x, y)
92 #define barrier(state, x, y) index(state, (state)->barriers, x, y)
98 static int xyd_cmp(void *av, void *bv) {
99 struct xyd *a = (struct xyd *)av;
100 struct xyd *b = (struct xyd *)bv;
109 if (a->direction < b->direction)
111 if (a->direction > b->direction)
116 static struct xyd *new_xyd(int x, int y, int direction)
118 struct xyd *xyd = snew(struct xyd);
121 xyd->direction = direction;
125 /* ----------------------------------------------------------------------
126 * Manage game parameters.
128 game_params *default_params(void)
130 game_params *ret = snew(game_params);
134 ret->wrapping = FALSE;
135 ret->barrier_probability = 0.0;
140 int game_fetch_preset(int i, char **name, game_params **params)
144 static const struct { int x, y, wrap; } values[] = {
157 if (i < 0 || i >= lenof(values))
160 ret = snew(game_params);
161 ret->width = values[i].x;
162 ret->height = values[i].y;
163 ret->wrapping = values[i].wrap;
164 ret->barrier_probability = 0.0;
166 sprintf(str, "%dx%d%s", ret->width, ret->height,
167 ret->wrapping ? " wrapping" : "");
174 void free_params(game_params *params)
179 game_params *dup_params(game_params *params)
181 game_params *ret = snew(game_params);
182 *ret = *params; /* structure copy */
186 config_item *game_configure(game_params *params)
191 ret = snewn(5, config_item);
193 ret[0].name = "Width";
194 ret[0].type = C_STRING;
195 sprintf(buf, "%d", params->width);
196 ret[0].sval = dupstr(buf);
199 ret[1].name = "Height";
200 ret[1].type = C_STRING;
201 sprintf(buf, "%d", params->height);
202 ret[1].sval = dupstr(buf);
205 ret[2].name = "Walls wrap around";
206 ret[2].type = C_BOOLEAN;
208 ret[2].ival = params->wrapping;
210 ret[3].name = "Barrier probability";
211 ret[3].type = C_STRING;
212 sprintf(buf, "%g", params->barrier_probability);
213 ret[3].sval = dupstr(buf);
224 game_params *custom_params(config_item *cfg)
226 game_params *ret = snew(game_params);
228 ret->width = atoi(cfg[0].sval);
229 ret->height = atoi(cfg[1].sval);
230 ret->wrapping = cfg[2].ival;
231 ret->barrier_probability = (float)atof(cfg[3].sval);
236 char *validate_params(game_params *params)
238 if (params->width <= 0 && params->height <= 0)
239 return "Width and height must both be greater than zero";
240 if (params->width <= 0)
241 return "Width must be greater than zero";
242 if (params->height <= 0)
243 return "Height must be greater than zero";
244 if (params->width <= 1 && params->height <= 1)
245 return "At least one of width and height must be greater than one";
246 if (params->barrier_probability < 0)
247 return "Barrier probability may not be negative";
248 if (params->barrier_probability > 1)
249 return "Barrier probability may not be greater than 1";
253 /* ----------------------------------------------------------------------
254 * Randomly select a new game seed.
257 char *new_game_seed(game_params *params, random_state *rs)
260 * The full description of a Net game is far too large to
261 * encode directly in the seed, so by default we'll have to go
262 * for the simple approach of providing a random-number seed.
264 * (This does not restrict me from _later on_ inventing a seed
265 * string syntax which can never be generated by this code -
266 * for example, strings beginning with a letter - allowing me
267 * to type in a precise game, and have new_game detect it and
268 * understand it and do something completely different.)
271 sprintf(buf, "%lu", random_bits(rs, 32));
275 char *validate_seed(game_params *params, char *seed)
278 * Since any string at all will suffice to seed the RNG, there
279 * is no validation required.
284 /* ----------------------------------------------------------------------
285 * Construct an initial game state, given a seed and parameters.
288 game_state *new_game(game_params *params, char *seed)
292 tree234 *possibilities, *barriers;
293 int w, h, x, y, nbarriers;
295 assert(params->width > 0 && params->height > 0);
296 assert(params->width > 1 || params->height > 1);
299 * Create a blank game state.
301 state = snew(game_state);
302 w = state->width = params->width;
303 h = state->height = params->height;
304 state->cx = state->width / 2;
305 state->cy = state->height / 2;
306 state->wrapping = params->wrapping;
307 state->last_rotate_dir = +1; /* *shrug* */
308 state->completed = FALSE;
309 state->tiles = snewn(state->width * state->height, unsigned char);
310 memset(state->tiles, 0, state->width * state->height);
311 state->barriers = snewn(state->width * state->height, unsigned char);
312 memset(state->barriers, 0, state->width * state->height);
315 * Set up border barriers if this is a non-wrapping game.
317 if (!state->wrapping) {
318 for (x = 0; x < state->width; x++) {
319 barrier(state, x, 0) |= U;
320 barrier(state, x, state->height-1) |= D;
322 for (y = 0; y < state->height; y++) {
323 barrier(state, 0, y) |= L;
324 barrier(state, state->width-1, y) |= R;
329 * Seed the internal random number generator.
331 rs = random_init(seed, strlen(seed));
334 * Construct the unshuffled grid.
336 * To do this, we simply start at the centre point, repeatedly
337 * choose a random possibility out of the available ways to
338 * extend a used square into an unused one, and do it. After
339 * extending the third line out of a square, we remove the
340 * fourth from the possibilities list to avoid any full-cross
341 * squares (which would make the game too easy because they
342 * only have one orientation).
344 * The slightly worrying thing is the avoidance of full-cross
345 * squares. Can this cause our unsophisticated construction
346 * algorithm to paint itself into a corner, by getting into a
347 * situation where there are some unreached squares and the
348 * only way to reach any of them is to extend a T-piece into a
351 * Answer: no it can't, and here's a proof.
353 * Any contiguous group of such unreachable squares must be
354 * surrounded on _all_ sides by T-pieces pointing away from the
355 * group. (If not, then there is a square which can be extended
356 * into one of the `unreachable' ones, and so it wasn't
357 * unreachable after all.) In particular, this implies that
358 * each contiguous group of unreachable squares must be
359 * rectangular in shape (any deviation from that yields a
360 * non-T-piece next to an `unreachable' square).
362 * So we have a rectangle of unreachable squares, with T-pieces
363 * forming a solid border around the rectangle. The corners of
364 * that border must be connected (since every tile connects all
365 * the lines arriving in it), and therefore the border must
366 * form a closed loop around the rectangle.
368 * But this can't have happened in the first place, since we
369 * _know_ we've avoided creating closed loops! Hence, no such
370 * situation can ever arise, and the naive grid construction
371 * algorithm will guaranteeably result in a complete grid
372 * containing no unreached squares, no full crosses _and_ no
375 possibilities = newtree234(xyd_cmp);
377 if (state->cx+1 < state->width)
378 add234(possibilities, new_xyd(state->cx, state->cy, R));
379 if (state->cy-1 >= 0)
380 add234(possibilities, new_xyd(state->cx, state->cy, U));
381 if (state->cx-1 >= 0)
382 add234(possibilities, new_xyd(state->cx, state->cy, L));
383 if (state->cy+1 < state->height)
384 add234(possibilities, new_xyd(state->cx, state->cy, D));
386 while (count234(possibilities) > 0) {
389 int x1, y1, d1, x2, y2, d2, d;
392 * Extract a randomly chosen possibility from the list.
394 i = random_upto(rs, count234(possibilities));
395 xyd = delpos234(possibilities, i);
401 OFFSET(x2, y2, x1, y1, d1, state);
404 printf("picked (%d,%d,%c) <-> (%d,%d,%c)\n",
405 x1, y1, "0RU3L567D9abcdef"[d1], x2, y2, "0RU3L567D9abcdef"[d2]);
409 * Make the connection. (We should be moving to an as yet
412 tile(state, x1, y1) |= d1;
413 assert(tile(state, x2, y2) == 0);
414 tile(state, x2, y2) |= d2;
417 * If we have created a T-piece, remove its last
420 if (COUNT(tile(state, x1, y1)) == 3) {
421 struct xyd xyd1, *xydp;
425 xyd1.direction = 0x0F ^ tile(state, x1, y1);
427 xydp = find234(possibilities, &xyd1, NULL);
431 printf("T-piece; removing (%d,%d,%c)\n",
432 xydp->x, xydp->y, "0RU3L567D9abcdef"[xydp->direction]);
434 del234(possibilities, xydp);
440 * Remove all other possibilities that were pointing at the
441 * tile we've just moved into.
443 for (d = 1; d < 0x10; d <<= 1) {
445 struct xyd xyd1, *xydp;
447 OFFSET(x3, y3, x2, y2, d, state);
454 xydp = find234(possibilities, &xyd1, NULL);
458 printf("Loop avoidance; removing (%d,%d,%c)\n",
459 xydp->x, xydp->y, "0RU3L567D9abcdef"[xydp->direction]);
461 del234(possibilities, xydp);
467 * Add new possibilities to the list for moving _out_ of
468 * the tile we have just moved into.
470 for (d = 1; d < 0x10; d <<= 1) {
474 continue; /* we've got this one already */
476 if (!state->wrapping) {
477 if (d == U && y2 == 0)
479 if (d == D && y2 == state->height-1)
481 if (d == L && x2 == 0)
483 if (d == R && x2 == state->width-1)
487 OFFSET(x3, y3, x2, y2, d, state);
489 if (tile(state, x3, y3))
490 continue; /* this would create a loop */
493 printf("New frontier; adding (%d,%d,%c)\n",
494 x2, y2, "0RU3L567D9abcdef"[d]);
496 add234(possibilities, new_xyd(x2, y2, d));
499 /* Having done that, we should have no possibilities remaining. */
500 assert(count234(possibilities) == 0);
501 freetree234(possibilities);
504 * Now compute a list of the possible barrier locations.
506 barriers = newtree234(xyd_cmp);
507 for (y = 0; y < state->height; y++) {
508 for (x = 0; x < state->width; x++) {
510 if (!(tile(state, x, y) & R) &&
511 (state->wrapping || x < state->width-1))
512 add234(barriers, new_xyd(x, y, R));
513 if (!(tile(state, x, y) & D) &&
514 (state->wrapping || y < state->height-1))
515 add234(barriers, new_xyd(x, y, D));
520 * Now shuffle the grid.
522 for (y = 0; y < state->height; y++) {
523 for (x = 0; x < state->width; x++) {
524 int orig = tile(state, x, y);
525 int rot = random_upto(rs, 4);
526 tile(state, x, y) = ROT(orig, rot);
531 * And now choose barrier locations. (We carefully do this
532 * _after_ shuffling, so that changing the barrier rate in the
533 * params while keeping the game seed the same will give the
534 * same shuffled grid and _only_ change the barrier locations.
535 * Also the way we choose barrier locations, by repeatedly
536 * choosing one possibility from the list until we have enough,
537 * is designed to ensure that raising the barrier rate while
538 * keeping the seed the same will provide a superset of the
539 * previous barrier set - i.e. if you ask for 10 barriers, and
540 * then decide that's still too hard and ask for 20, you'll get
541 * the original 10 plus 10 more, rather than getting 20 new
542 * ones and the chance of remembering your first 10.)
544 nbarriers = (int)(params->barrier_probability * count234(barriers));
545 assert(nbarriers >= 0 && nbarriers <= count234(barriers));
547 while (nbarriers > 0) {
550 int x1, y1, d1, x2, y2, d2;
553 * Extract a randomly chosen barrier from the list.
555 i = random_upto(rs, count234(barriers));
556 xyd = delpos234(barriers, i);
565 OFFSET(x2, y2, x1, y1, d1, state);
568 barrier(state, x1, y1) |= d1;
569 barrier(state, x2, y2) |= d2;
575 * Clean up the rest of the barrier list.
580 while ( (xyd = delpos234(barriers, 0)) != NULL)
583 freetree234(barriers);
587 * Set up the barrier corner flags, for drawing barriers
588 * prettily when they meet.
590 for (y = 0; y < state->height; y++) {
591 for (x = 0; x < state->width; x++) {
594 for (dir = 1; dir < 0x10; dir <<= 1) {
596 int x1, y1, x2, y2, x3, y3;
599 if (!(barrier(state, x, y) & dir))
602 if (barrier(state, x, y) & dir2)
605 x1 = x + X(dir), y1 = y + Y(dir);
606 if (x1 >= 0 && x1 < state->width &&
607 y1 >= 0 && y1 < state->height &&
608 (barrier(state, x1, y1) & dir2))
611 x2 = x + X(dir2), y2 = y + Y(dir2);
612 if (x2 >= 0 && x2 < state->width &&
613 y2 >= 0 && y2 < state->height &&
614 (barrier(state, x2, y2) & dir))
618 barrier(state, x, y) |= (dir << 4);
619 if (x1 >= 0 && x1 < state->width &&
620 y1 >= 0 && y1 < state->height)
621 barrier(state, x1, y1) |= (A(dir) << 4);
622 if (x2 >= 0 && x2 < state->width &&
623 y2 >= 0 && y2 < state->height)
624 barrier(state, x2, y2) |= (C(dir) << 4);
625 x3 = x + X(dir) + X(dir2), y3 = y + Y(dir) + Y(dir2);
626 if (x3 >= 0 && x3 < state->width &&
627 y3 >= 0 && y3 < state->height)
628 barrier(state, x3, y3) |= (F(dir) << 4);
639 game_state *dup_game(game_state *state)
643 ret = snew(game_state);
644 ret->width = state->width;
645 ret->height = state->height;
648 ret->wrapping = state->wrapping;
649 ret->completed = state->completed;
650 ret->last_rotate_dir = state->last_rotate_dir;
651 ret->tiles = snewn(state->width * state->height, unsigned char);
652 memcpy(ret->tiles, state->tiles, state->width * state->height);
653 ret->barriers = snewn(state->width * state->height, unsigned char);
654 memcpy(ret->barriers, state->barriers, state->width * state->height);
659 void free_game(game_state *state)
662 sfree(state->barriers);
666 /* ----------------------------------------------------------------------
671 * Compute which squares are reachable from the centre square, as a
672 * quick visual aid to determining how close the game is to
673 * completion. This is also a simple way to tell if the game _is_
674 * completed - just call this function and see whether every square
677 static unsigned char *compute_active(game_state *state)
679 unsigned char *active;
683 active = snewn(state->width * state->height, unsigned char);
684 memset(active, 0, state->width * state->height);
687 * We only store (x,y) pairs in todo, but it's easier to reuse
688 * xyd_cmp and just store direction 0 every time.
690 todo = newtree234(xyd_cmp);
691 index(state, active, state->cx, state->cy) = ACTIVE;
692 add234(todo, new_xyd(state->cx, state->cy, 0));
694 while ( (xyd = delpos234(todo, 0)) != NULL) {
695 int x1, y1, d1, x2, y2, d2;
701 for (d1 = 1; d1 < 0x10; d1 <<= 1) {
702 OFFSET(x2, y2, x1, y1, d1, state);
706 * If the next tile in this direction is connected to
707 * us, and there isn't a barrier in the way, and it
708 * isn't already marked active, then mark it active and
709 * add it to the to-examine list.
711 if ((tile(state, x1, y1) & d1) &&
712 (tile(state, x2, y2) & d2) &&
713 !(barrier(state, x1, y1) & d1) &&
714 !index(state, active, x2, y2)) {
715 index(state, active, x2, y2) = ACTIVE;
716 add234(todo, new_xyd(x2, y2, 0));
720 /* Now we expect the todo list to have shrunk to zero size. */
721 assert(count234(todo) == 0);
727 /* ----------------------------------------------------------------------
730 game_state *make_move(game_state *state, int x, int y, int button)
736 * All moves in Net are made with the mouse.
738 if (button != LEFT_BUTTON &&
739 button != MIDDLE_BUTTON &&
740 button != RIGHT_BUTTON)
744 * The button must have been clicked on a valid tile.
746 x -= WINDOW_OFFSET + TILE_BORDER;
747 y -= WINDOW_OFFSET + TILE_BORDER;
752 if (tx >= state->width || ty >= state->height)
754 if (tx % TILE_SIZE >= TILE_SIZE - TILE_BORDER ||
755 ty % TILE_SIZE >= TILE_SIZE - TILE_BORDER)
759 * The middle button locks or unlocks a tile. (A locked tile
760 * cannot be turned, and is visually marked as being locked.
761 * This is a convenience for the player, so that once they are
762 * sure which way round a tile goes, they can lock it and thus
763 * avoid forgetting later on that they'd already done that one;
764 * and the locking also prevents them turning the tile by
765 * accident. If they change their mind, another middle click
768 if (button == MIDDLE_BUTTON) {
769 ret = dup_game(state);
770 tile(ret, tx, ty) ^= LOCKED;
775 * The left and right buttons have no effect if clicked on a
778 if (tile(state, tx, ty) & LOCKED)
782 * Otherwise, turn the tile one way or the other. Left button
783 * turns anticlockwise; right button turns clockwise.
785 ret = dup_game(state);
786 orig = tile(ret, tx, ty);
787 if (button == LEFT_BUTTON) {
788 tile(ret, tx, ty) = A(orig);
789 ret->last_rotate_dir = +1;
791 tile(ret, tx, ty) = C(orig);
792 ret->last_rotate_dir = -1;
796 * Check whether the game has been completed.
799 unsigned char *active = compute_active(ret);
803 for (x1 = 0; x1 < ret->width; x1++)
804 for (y1 = 0; y1 < ret->height; y1++)
805 if (!index(ret, active, x1, y1)) {
807 goto break_label; /* break out of two loops at once */
814 ret->completed = TRUE;
820 /* ----------------------------------------------------------------------
821 * Routines for drawing the game position on the screen.
824 struct game_drawstate {
827 unsigned char *visible;
830 game_drawstate *game_new_drawstate(game_state *state)
832 game_drawstate *ds = snew(game_drawstate);
835 ds->width = state->width;
836 ds->height = state->height;
837 ds->visible = snewn(state->width * state->height, unsigned char);
838 memset(ds->visible, 0xFF, state->width * state->height);
843 void game_free_drawstate(game_drawstate *ds)
849 void game_size(game_params *params, int *x, int *y)
851 *x = WINDOW_OFFSET * 2 + TILE_SIZE * params->width + TILE_BORDER;
852 *y = WINDOW_OFFSET * 2 + TILE_SIZE * params->height + TILE_BORDER;
855 float *game_colours(frontend *fe, game_state *state, int *ncolours)
859 ret = snewn(NCOLOURS * 3, float);
860 *ncolours = NCOLOURS;
863 * Basic background colour is whatever the front end thinks is
864 * a sensible default.
866 frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
871 ret[COL_WIRE * 3 + 0] = 0.0F;
872 ret[COL_WIRE * 3 + 1] = 0.0F;
873 ret[COL_WIRE * 3 + 2] = 0.0F;
876 * Powered wires and powered endpoints are cyan.
878 ret[COL_POWERED * 3 + 0] = 0.0F;
879 ret[COL_POWERED * 3 + 1] = 1.0F;
880 ret[COL_POWERED * 3 + 2] = 1.0F;
885 ret[COL_BARRIER * 3 + 0] = 1.0F;
886 ret[COL_BARRIER * 3 + 1] = 0.0F;
887 ret[COL_BARRIER * 3 + 2] = 0.0F;
890 * Unpowered endpoints are blue.
892 ret[COL_ENDPOINT * 3 + 0] = 0.0F;
893 ret[COL_ENDPOINT * 3 + 1] = 0.0F;
894 ret[COL_ENDPOINT * 3 + 2] = 1.0F;
897 * Tile borders are a darker grey than the background.
899 ret[COL_BORDER * 3 + 0] = 0.5F * ret[COL_BACKGROUND * 3 + 0];
900 ret[COL_BORDER * 3 + 1] = 0.5F * ret[COL_BACKGROUND * 3 + 1];
901 ret[COL_BORDER * 3 + 2] = 0.5F * ret[COL_BACKGROUND * 3 + 2];
904 * Locked tiles are a grey in between those two.
906 ret[COL_LOCKED * 3 + 0] = 0.75F * ret[COL_BACKGROUND * 3 + 0];
907 ret[COL_LOCKED * 3 + 1] = 0.75F * ret[COL_BACKGROUND * 3 + 1];
908 ret[COL_LOCKED * 3 + 2] = 0.75F * ret[COL_BACKGROUND * 3 + 2];
913 static void draw_thick_line(frontend *fe, int x1, int y1, int x2, int y2,
916 draw_line(fe, x1-1, y1, x2-1, y2, COL_WIRE);
917 draw_line(fe, x1+1, y1, x2+1, y2, COL_WIRE);
918 draw_line(fe, x1, y1-1, x2, y2-1, COL_WIRE);
919 draw_line(fe, x1, y1+1, x2, y2+1, COL_WIRE);
920 draw_line(fe, x1, y1, x2, y2, colour);
923 static void draw_rect_coords(frontend *fe, int x1, int y1, int x2, int y2,
926 int mx = (x1 < x2 ? x1 : x2);
927 int my = (y1 < y2 ? y1 : y2);
928 int dx = (x2 + x1 - 2*mx + 1);
929 int dy = (y2 + y1 - 2*my + 1);
931 draw_rect(fe, mx, my, dx, dy, colour);
934 static void draw_barrier_corner(frontend *fe, int x, int y, int dir, int phase)
936 int bx = WINDOW_OFFSET + TILE_SIZE * x;
937 int by = WINDOW_OFFSET + TILE_SIZE * y;
938 int x1, y1, dx, dy, dir2;
943 dx = X(dir) + X(dir2);
944 dy = Y(dir) + Y(dir2);
945 x1 = (dx > 0 ? TILE_SIZE+TILE_BORDER-1 : 0);
946 y1 = (dy > 0 ? TILE_SIZE+TILE_BORDER-1 : 0);
949 draw_rect_coords(fe, bx+x1, by+y1,
950 bx+x1-TILE_BORDER*dx, by+y1-(TILE_BORDER-1)*dy,
952 draw_rect_coords(fe, bx+x1, by+y1,
953 bx+x1-(TILE_BORDER-1)*dx, by+y1-TILE_BORDER*dy,
956 draw_rect_coords(fe, bx+x1, by+y1,
957 bx+x1-(TILE_BORDER-1)*dx, by+y1-(TILE_BORDER-1)*dy,
962 static void draw_barrier(frontend *fe, int x, int y, int dir, int phase)
964 int bx = WINDOW_OFFSET + TILE_SIZE * x;
965 int by = WINDOW_OFFSET + TILE_SIZE * y;
968 x1 = (X(dir) > 0 ? TILE_SIZE : X(dir) == 0 ? TILE_BORDER : 0);
969 y1 = (Y(dir) > 0 ? TILE_SIZE : Y(dir) == 0 ? TILE_BORDER : 0);
970 w = (X(dir) ? TILE_BORDER : TILE_SIZE - TILE_BORDER);
971 h = (Y(dir) ? TILE_BORDER : TILE_SIZE - TILE_BORDER);
974 draw_rect(fe, bx+x1-X(dir), by+y1-Y(dir), w, h, COL_WIRE);
976 draw_rect(fe, bx+x1, by+y1, w, h, COL_BARRIER);
980 static void draw_tile(frontend *fe, game_state *state, int x, int y, int tile,
983 int bx = WINDOW_OFFSET + TILE_SIZE * x;
984 int by = WINDOW_OFFSET + TILE_SIZE * y;
986 float cx, cy, ex, ey, tx, ty;
990 * When we draw a single tile, we must draw everything up to
991 * and including the borders around the tile. This means that
992 * if the neighbouring tiles have connections to those borders,
993 * we must draw those connections on the borders themselves.
995 * This would be terribly fiddly if we ever had to draw a tile
996 * while its neighbour was in mid-rotate, because we'd have to
997 * arrange to _know_ that the neighbour was being rotated and
998 * hence had an anomalous effect on the redraw of this tile.
999 * Fortunately, the drawing algorithm avoids ever calling us in
1000 * this circumstance: we're either drawing lots of straight
1001 * tiles at game start or after a move is complete, or we're
1002 * repeatedly drawing only the rotating tile. So no problem.
1006 * So. First blank the tile out completely: draw a big
1007 * rectangle in border colour, and a smaller rectangle in
1008 * background colour to fill it in.
1010 draw_rect(fe, bx, by, TILE_SIZE+TILE_BORDER, TILE_SIZE+TILE_BORDER,
1012 draw_rect(fe, bx+TILE_BORDER, by+TILE_BORDER,
1013 TILE_SIZE-TILE_BORDER, TILE_SIZE-TILE_BORDER,
1014 tile & LOCKED ? COL_LOCKED : COL_BACKGROUND);
1017 * Set up the rotation matrix.
1019 matrix[0] = (float)cos(angle * PI / 180.0);
1020 matrix[1] = (float)-sin(angle * PI / 180.0);
1021 matrix[2] = (float)sin(angle * PI / 180.0);
1022 matrix[3] = (float)cos(angle * PI / 180.0);
1027 cx = cy = TILE_BORDER + (TILE_SIZE-TILE_BORDER) / 2.0F - 0.5F;
1028 col = (tile & ACTIVE ? COL_POWERED : COL_WIRE);
1029 for (dir = 1; dir < 0x10; dir <<= 1) {
1031 ex = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * X(dir);
1032 ey = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * Y(dir);
1033 MATMUL(tx, ty, matrix, ex, ey);
1034 draw_thick_line(fe, bx+(int)cx, by+(int)cy,
1035 bx+(int)(cx+tx), by+(int)(cy+ty),
1039 for (dir = 1; dir < 0x10; dir <<= 1) {
1041 ex = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * X(dir);
1042 ey = (TILE_SIZE - TILE_BORDER - 1.0F) / 2.0F * Y(dir);
1043 MATMUL(tx, ty, matrix, ex, ey);
1044 draw_line(fe, bx+(int)cx, by+(int)cy,
1045 bx+(int)(cx+tx), by+(int)(cy+ty), col);
1050 * Draw the box in the middle. We do this in blue if the tile
1051 * is an unpowered endpoint, in cyan if the tile is a powered
1052 * endpoint, in black if the tile is the centrepiece, and
1053 * otherwise not at all.
1056 if (x == state->cx && y == state->cy)
1058 else if (COUNT(tile) == 1) {
1059 col = (tile & ACTIVE ? COL_POWERED : COL_ENDPOINT);
1064 points[0] = +1; points[1] = +1;
1065 points[2] = +1; points[3] = -1;
1066 points[4] = -1; points[5] = -1;
1067 points[6] = -1; points[7] = +1;
1069 for (i = 0; i < 8; i += 2) {
1070 ex = (TILE_SIZE * 0.24F) * points[i];
1071 ey = (TILE_SIZE * 0.24F) * points[i+1];
1072 MATMUL(tx, ty, matrix, ex, ey);
1073 points[i] = bx+(int)(cx+tx);
1074 points[i+1] = by+(int)(cy+ty);
1077 draw_polygon(fe, points, 4, TRUE, col);
1078 draw_polygon(fe, points, 4, FALSE, COL_WIRE);
1082 * Draw the points on the border if other tiles are connected
1085 for (dir = 1; dir < 0x10; dir <<= 1) {
1086 int dx, dy, px, py, lx, ly, vx, vy, ox, oy;
1094 if (ox < 0 || ox >= state->width || oy < 0 || oy >= state->height)
1097 if (!(tile(state, ox, oy) & F(dir)))
1100 px = bx + (int)(dx>0 ? TILE_SIZE + TILE_BORDER - 1 : dx<0 ? 0 : cx);
1101 py = by + (int)(dy>0 ? TILE_SIZE + TILE_BORDER - 1 : dy<0 ? 0 : cy);
1102 lx = dx * (TILE_BORDER-1);
1103 ly = dy * (TILE_BORDER-1);
1107 if (angle == 0.0 && (tile & dir)) {
1109 * If we are fully connected to the other tile, we must
1110 * draw right across the tile border. (We can use our
1111 * own ACTIVE state to determine what colour to do this
1112 * in: if we are fully connected to the other tile then
1113 * the two ACTIVE states will be the same.)
1115 draw_rect_coords(fe, px-vx, py-vy, px+lx+vx, py+ly+vy, COL_WIRE);
1116 draw_rect_coords(fe, px, py, px+lx, py+ly,
1117 (tile & ACTIVE) ? COL_POWERED : COL_WIRE);
1120 * The other tile extends into our border, but isn't
1121 * actually connected to us. Just draw a single black
1124 draw_rect_coords(fe, px, py, px, py, COL_WIRE);
1129 * Draw barrier corners, and then barriers.
1131 for (phase = 0; phase < 2; phase++) {
1132 for (dir = 1; dir < 0x10; dir <<= 1)
1133 if (barrier(state, x, y) & (dir << 4))
1134 draw_barrier_corner(fe, x, y, dir << 4, phase);
1135 for (dir = 1; dir < 0x10; dir <<= 1)
1136 if (barrier(state, x, y) & dir)
1137 draw_barrier(fe, x, y, dir, phase);
1140 draw_update(fe, bx, by, TILE_SIZE+TILE_BORDER, TILE_SIZE+TILE_BORDER);
1143 void game_redraw(frontend *fe, game_drawstate *ds, game_state *oldstate,
1144 game_state *state, float t, float ft)
1146 int x, y, tx, ty, frame;
1147 unsigned char *active;
1151 * Clear the screen and draw the exterior barrier lines if this
1152 * is our first call.
1160 WINDOW_OFFSET * 2 + TILE_SIZE * state->width + TILE_BORDER,
1161 WINDOW_OFFSET * 2 + TILE_SIZE * state->height + TILE_BORDER,
1163 draw_update(fe, 0, 0,
1164 WINDOW_OFFSET*2 + TILE_SIZE*state->width + TILE_BORDER,
1165 WINDOW_OFFSET*2 + TILE_SIZE*state->height + TILE_BORDER);
1167 for (phase = 0; phase < 2; phase++) {
1169 for (x = 0; x < ds->width; x++) {
1170 if (barrier(state, x, 0) & UL)
1171 draw_barrier_corner(fe, x, -1, LD, phase);
1172 if (barrier(state, x, 0) & RU)
1173 draw_barrier_corner(fe, x, -1, DR, phase);
1174 if (barrier(state, x, 0) & U)
1175 draw_barrier(fe, x, -1, D, phase);
1176 if (barrier(state, x, ds->height-1) & DR)
1177 draw_barrier_corner(fe, x, ds->height, RU, phase);
1178 if (barrier(state, x, ds->height-1) & LD)
1179 draw_barrier_corner(fe, x, ds->height, UL, phase);
1180 if (barrier(state, x, ds->height-1) & D)
1181 draw_barrier(fe, x, ds->height, U, phase);
1184 for (y = 0; y < ds->height; y++) {
1185 if (barrier(state, 0, y) & UL)
1186 draw_barrier_corner(fe, -1, y, RU, phase);
1187 if (barrier(state, 0, y) & LD)
1188 draw_barrier_corner(fe, -1, y, DR, phase);
1189 if (barrier(state, 0, y) & L)
1190 draw_barrier(fe, -1, y, R, phase);
1191 if (barrier(state, ds->width-1, y) & RU)
1192 draw_barrier_corner(fe, ds->width, y, UL, phase);
1193 if (barrier(state, ds->width-1, y) & DR)
1194 draw_barrier_corner(fe, ds->width, y, LD, phase);
1195 if (barrier(state, ds->width-1, y) & R)
1196 draw_barrier(fe, ds->width, y, L, phase);
1202 if (oldstate && (t < ROTATE_TIME)) {
1204 * We're animating a tile rotation. Find the turning tile,
1207 for (x = 0; x < oldstate->width; x++)
1208 for (y = 0; y < oldstate->height; y++)
1209 if ((tile(oldstate, x, y) ^ tile(state, x, y)) & 0xF) {
1211 goto break_label; /* leave both loops at once */
1216 if (tile(state, tx, ty) == ROT(tile(oldstate, tx, ty),
1217 state->last_rotate_dir))
1218 angle = state->last_rotate_dir * 90.0F * (t / ROTATE_TIME);
1220 angle = state->last_rotate_dir * -90.0F * (t / ROTATE_TIME);
1228 * We're animating a completion flash. Find which frame
1231 frame = (int)(ft / FLASH_FRAME);
1235 * Draw any tile which differs from the way it was last drawn.
1237 active = compute_active(state);
1239 for (x = 0; x < ds->width; x++)
1240 for (y = 0; y < ds->height; y++) {
1241 unsigned char c = tile(state, x, y) | index(state, active, x, y);
1244 * In a completion flash, we adjust the LOCKED bit
1245 * depending on our distance from the centre point and
1249 int xdist, ydist, dist;
1250 xdist = (x < state->cx ? state->cx - x : x - state->cx);
1251 ydist = (y < state->cy ? state->cy - y : y - state->cy);
1252 dist = (xdist > ydist ? xdist : ydist);
1254 if (frame >= dist && frame < dist+4) {
1255 int lock = (frame - dist) & 1;
1256 lock = lock ? LOCKED : 0;
1257 c = (c &~ LOCKED) | lock;
1261 if (index(state, ds->visible, x, y) != c ||
1262 index(state, ds->visible, x, y) == 0xFF ||
1263 (x == tx && y == ty)) {
1264 draw_tile(fe, state, x, y, c,
1265 (x == tx && y == ty ? angle : 0.0F));
1266 if (x == tx && y == ty)
1267 index(state, ds->visible, x, y) = 0xFF;
1269 index(state, ds->visible, x, y) = c;
1274 * Update the status bar.
1277 char statusbuf[256];
1280 n = state->width * state->height;
1281 for (i = a = 0; i < n; i++)
1285 sprintf(statusbuf, "%sActive: %d/%d",
1286 (state->completed ? "COMPLETED! " : ""), a, n);
1288 status_bar(fe, statusbuf);
1294 float game_anim_length(game_state *oldstate, game_state *newstate)
1299 * If there's a tile which has been rotated, allow time to
1300 * animate its rotation.
1302 for (x = 0; x < oldstate->width; x++)
1303 for (y = 0; y < oldstate->height; y++)
1304 if ((tile(oldstate, x, y) ^ tile(newstate, x, y)) & 0xF) {
1311 float game_flash_length(game_state *oldstate, game_state *newstate)
1314 * If the game has just been completed, we display a completion
1317 if (!oldstate->completed && newstate->completed) {
1320 if (size < newstate->cx+1)
1321 size = newstate->cx+1;
1322 if (size < newstate->cy+1)
1323 size = newstate->cy+1;
1324 if (size < newstate->width - newstate->cx)
1325 size = newstate->width - newstate->cx;
1326 if (size < newstate->height - newstate->cy)
1327 size = newstate->height - newstate->cy;
1328 return FLASH_FRAME * (size+4);
1334 int game_wants_statusbar(void)