X-Git-Url: https://git.distorted.org.uk/~mdw/sgt/puzzles/blobdiff_plain/f4afe2069b1c51f0982069c13ac6679ea7a3ce00..59dae0db4e2110631e1c7f2ea5990f6b406aff6e:/flip.c diff --git a/flip.c b/flip.c index fd31647..4f78ec7 100644 --- a/flip.c +++ b/flip.c @@ -3,15 +3,6 @@ * where each click toggles an overlapping set of lights. */ -/* - * TODO: - * - * - `Solve' could mark the squares you must click to solve - * + infrastructure change: this would mean the Solve operation - * must receive the current game_state as well as the initial - * one, which I've been wondering about for a while - */ - #include #include #include @@ -28,6 +19,7 @@ enum { COL_RIGHT, COL_GRID, COL_DIAG, + COL_HINT, NCOLOURS }; @@ -37,6 +29,7 @@ enum { #define COORD(x) ( (x) * TILE_SIZE + BORDER ) #define FROMCOORD(x) ( ((x) - BORDER + TILE_SIZE) / TILE_SIZE - 1 ) +#define ANIM_TIME 0.25F #define FLASH_FRAME 0.07F /* @@ -64,7 +57,7 @@ struct matrix { struct game_state { int w, h; - int moves, completed; + int moves, completed, cheated, hints_active; unsigned char *grid; /* array of w*h */ struct matrix *matrix; }; @@ -354,7 +347,7 @@ static void addneighbours(tree234 *t, int w, int h, int cx, int cy, } static char *new_game_desc(game_params *params, random_state *rs, - game_aux_info **aux, int interactive) + char **aux, int interactive) { int w = params->w, h = params->h, wh = w * h; int i, j; @@ -597,14 +590,11 @@ static char *new_game_desc(game_params *params, random_state *rs, sprintf(ret, "%s,%s", mbmp, gbmp); sfree(mbmp); sfree(gbmp); + sfree(matrix); + sfree(grid); return ret; } -static void game_free_aux_info(game_aux_info *aux) -{ - assert(!"Shouldn't happen"); -} - static char *validate_desc(game_params *params, char *desc) { int w = params->w, h = params->h, wh = w * h; @@ -632,6 +622,8 @@ static game_state *new_game(midend_data *me, game_params *params, char *desc) state->w = w; state->h = h; state->completed = FALSE; + state->cheated = FALSE; + state->hints_active = FALSE; state->moves = 0; state->matrix = snew(struct matrix); state->matrix->refcount = 1; @@ -650,6 +642,8 @@ static game_state *dup_game(game_state *state) ret->w = state->w; ret->h = state->h; ret->completed = state->completed; + ret->cheated = state->cheated; + ret->hints_active = state->hints_active; ret->moves = state->moves; ret->matrix = state->matrix; state->matrix->refcount++; @@ -669,10 +663,193 @@ static void free_game(game_state *state) sfree(state); } -static game_state *solve_game(game_state *state, game_aux_info *aux, - char **error) +static void rowxor(unsigned char *row1, unsigned char *row2, int len) { - return NULL; + int i; + for (i = 0; i < len; i++) + row1[i] ^= row2[i]; +} + +static char *solve_game(game_state *state, game_state *currstate, + char *aux, char **error) +{ + int w = state->w, h = state->h, wh = w * h; + unsigned char *equations, *solution, *shortest; + int *und, nund; + int rowsdone, colsdone; + int i, j, k, len, bestlen; + char *ret; + + /* + * Set up a list of simultaneous equations. Each one is of + * length (wh+1) and has wh coefficients followed by a value. + */ + equations = snewn((wh + 1) * wh, unsigned char); + for (i = 0; i < wh; i++) { + for (j = 0; j < wh; j++) + equations[i * (wh+1) + j] = currstate->matrix->matrix[j*wh+i]; + equations[i * (wh+1) + wh] = currstate->grid[i] & 1; + } + + /* + * Perform Gaussian elimination over GF(2). + */ + rowsdone = colsdone = 0; + nund = 0; + und = snewn(wh, int); + do { + /* + * Find the leftmost column which has a 1 in it somewhere + * outside the first `rowsdone' rows. + */ + j = -1; + for (i = colsdone; i < wh; i++) { + for (j = rowsdone; j < wh; j++) + if (equations[j * (wh+1) + i]) + break; + if (j < wh) + break; /* found one */ + /* + * This is a column which will not have an equation + * controlling it. Mark it as undetermined. + */ + und[nund++] = i; + } + + /* + * If there wasn't one, then we've finished: all remaining + * equations are of the form 0 = constant. Check to see if + * any of them wants 0 to be equal to 1; this is the + * condition which indicates an insoluble problem + * (therefore _hopefully_ one typed in by a user!). + */ + if (i == wh) { + for (j = rowsdone; j < wh; j++) + if (equations[j * (wh+1) + wh]) { + *error = "No solution exists for this position"; + sfree(equations); + sfree(und); + return NULL; + } + break; + } + + /* + * We've found a 1. It's in column i, and the topmost 1 in + * that column is in row j. Do a row-XOR to move it up to + * the topmost row if it isn't already there. + */ + assert(j != -1); + if (j > rowsdone) + rowxor(equations + rowsdone*(wh+1), equations + j*(wh+1), wh+1); + + /* + * Do row-XORs to eliminate that 1 from all rows below the + * topmost row. + */ + for (j = rowsdone + 1; j < wh; j++) + if (equations[j*(wh+1) + i]) + rowxor(equations + j*(wh+1), + equations + rowsdone*(wh+1), wh+1); + + /* + * Mark this row and column as done. + */ + rowsdone++; + colsdone = i+1; + + /* + * If we've done all the rows, terminate. + */ + } while (rowsdone < wh); + + /* + * If we reach here, we have the ability to produce a solution. + * So we go through _all_ possible solutions (each + * corresponding to a set of arbitrary choices of those + * components not directly determined by an equation), and pick + * one requiring the smallest number of flips. + */ + solution = snewn(wh, unsigned char); + shortest = snewn(wh, unsigned char); + memset(solution, 0, wh); + bestlen = wh + 1; + while (1) { + /* + * Find a solution based on the current values of the + * undetermined variables. + */ + for (j = rowsdone; j-- ;) { + int v; + + /* + * Find the leftmost set bit in this equation. + */ + for (i = 0; i < wh; i++) + if (equations[j * (wh+1) + i]) + break; + assert(i < wh); /* there must have been one! */ + + /* + * Compute this variable using the rest. + */ + v = equations[j * (wh+1) + wh]; + for (k = i+1; k < wh; k++) + if (equations[j * (wh+1) + k]) + v ^= solution[k]; + + solution[i] = v; + } + + /* + * Compare this solution to the current best one, and + * replace the best one if this one is shorter. + */ + len = 0; + for (i = 0; i < wh; i++) + if (solution[i]) + len++; + if (len < bestlen) { + bestlen = len; + memcpy(shortest, solution, wh); + } + + /* + * Now increment the binary number given by the + * undetermined variables: turn all 1s into 0s until we see + * a 0, at which point we turn it into a 1. + */ + for (i = 0; i < nund; i++) { + solution[und[i]] = !solution[und[i]]; + if (solution[und[i]]) + break; + } + + /* + * If we didn't find a 0 at any point, we have wrapped + * round and are back at the start, i.e. we have enumerated + * all solutions. + */ + if (i == nund) + break; + } + + /* + * We have a solution. Produce a move string encoding the + * solution. + */ + ret = snewn(wh + 2, char); + ret[0] = 'S'; + for (i = 0; i < wh; i++) + ret[i+1] = shortest[i] ? '1' : '0'; + ret[wh+1] = '\0'; + + sfree(shortest); + sfree(solution); + sfree(equations); + sfree(und); + + return ret; } static char *game_text_format(game_state *state) @@ -689,6 +866,15 @@ static void free_ui(game_ui *ui) { } +static char *encode_ui(game_ui *ui) +{ + return NULL; +} + +static void decode_ui(game_ui *ui, char *encoding) +{ +} + static void game_changed_state(game_ui *ui, game_state *oldstate, game_state *newstate) { @@ -700,38 +886,68 @@ struct game_drawstate { int tilesize; }; -static game_state *make_move(game_state *from, game_ui *ui, game_drawstate *ds, - int x, int y, int button) +static char *interpret_move(game_state *state, game_ui *ui, game_drawstate *ds, + int x, int y, int button) { - int w = from->w, h = from->h, wh = w * h; - game_state *ret; + int w = state->w, h = state->h /*, wh = w * h */; + char buf[80]; if (button == LEFT_BUTTON) { int tx = FROMCOORD(x), ty = FROMCOORD(y); if (tx >= 0 && tx < w && ty >= 0 && ty < h) { - int i, j, done; + sprintf(buf, "M%d,%d", tx, ty); + return dupstr(buf); + } + } - ret = dup_game(from); + return NULL; +} - if (!ret->completed) - ret->moves++; +static game_state *execute_move(game_state *from, char *move) +{ + int w = from->w, h = from->h, wh = w * h; + game_state *ret; + int x, y; + + if (move[0] == 'S' && strlen(move) == wh+1) { + int i; + + ret = dup_game(from); + ret->hints_active = TRUE; + ret->cheated = TRUE; + for (i = 0; i < wh; i++) { + ret->grid[i] &= ~2; + if (move[i+1] != '0') + ret->grid[i] |= 2; + } + return ret; + } else if (move[0] == 'M' && + sscanf(move+1, "%d,%d", &x, &y) == 2 && + x >= 0 && x < w && y >= 0 && y < h) { + int i, j, done; - i = ty * w + tx; + ret = dup_game(from); - done = TRUE; - for (j = 0; j < wh; j++) { - ret->grid[j] ^= ret->matrix->matrix[i*wh+j]; - if (ret->grid[j] & 1) - done = FALSE; - } - if (done) - ret->completed = TRUE; + if (!ret->completed) + ret->moves++; - return ret; - } - } + i = y * w + x; - return NULL; + done = TRUE; + for (j = 0; j < wh; j++) { + ret->grid[j] ^= ret->matrix->matrix[i*wh+j]; + if (ret->grid[j] & 1) + done = FALSE; + } + ret->grid[i] ^= 2; /* toggle hint */ + if (done) { + ret->completed = TRUE; + ret->hints_active = FALSE; + } + + return ret; + } else + return NULL; /* can't parse move string */ } /* ---------------------------------------------------------------------- @@ -781,6 +997,10 @@ static float *game_colours(frontend *fe, game_state *state, int *ncolours) ret[COL_DIAG * 3 + 1] = ret[COL_GRID * 3 + 1]; ret[COL_DIAG * 3 + 2] = ret[COL_GRID * 3 + 2]; + ret[COL_HINT * 3 + 0] = 1.0F; + ret[COL_HINT * 3 + 1] = 0.0F; + ret[COL_HINT * 3 + 2] = 0.0F; + *ncolours = NCOLOURS; return ret; } @@ -808,7 +1028,8 @@ static void game_free_drawstate(game_drawstate *ds) } static void draw_tile(frontend *fe, game_drawstate *ds, - game_state *state, int x, int y, int tile) + game_state *state, int x, int y, int tile, int anim, + float animtime) { int w = ds->w, h = ds->h, wh = w * h; int bx = x * TILE_SIZE + BORDER, by = y * TILE_SIZE + BORDER; @@ -817,7 +1038,30 @@ static void draw_tile(frontend *fe, game_drawstate *ds, clip(fe, bx+1, by+1, TILE_SIZE-1, TILE_SIZE-1); draw_rect(fe, bx+1, by+1, TILE_SIZE-1, TILE_SIZE-1, - tile == 1 ? COL_WRONG : COL_RIGHT); + anim ? COL_BACKGROUND : tile & 1 ? COL_WRONG : COL_RIGHT); + if (anim) { + /* + * Draw a polygon indicating that the square is diagonally + * flipping over. + */ + int coords[8], colour; + + coords[0] = bx + TILE_SIZE; + coords[1] = by; + coords[2] = bx + TILE_SIZE * animtime; + coords[3] = by + TILE_SIZE * animtime; + coords[4] = bx; + coords[5] = by + TILE_SIZE; + coords[6] = bx + TILE_SIZE - TILE_SIZE * animtime; + coords[7] = by + TILE_SIZE - TILE_SIZE * animtime; + + colour = (tile & 1 ? COL_WRONG : COL_RIGHT); + if (animtime < 0.5) + colour = COL_WRONG + COL_RIGHT - colour; + + draw_polygon(fe, coords, 4, TRUE, colour); + draw_polygon(fe, coords, 4, FALSE, COL_GRID); + } /* * Draw a little diagram in the tile which indicates which @@ -840,6 +1084,22 @@ static void draw_tile(frontend *fe, game_drawstate *ds, } } + /* + * Draw a hint rectangle if required. + */ + if (tile & 2) { + int x1 = bx + TILE_SIZE / 20, x2 = bx + TILE_SIZE - TILE_SIZE / 20; + int y1 = by + TILE_SIZE / 20, y2 = by + TILE_SIZE - TILE_SIZE / 20; + int i = 3; + while (i--) { + draw_line(fe, x1, y1, x2, y1, COL_HINT); + draw_line(fe, x1, y2, x2, y2, COL_HINT); + draw_line(fe, x1, y1, x1, y2, COL_HINT); + draw_line(fe, x2, y1, x2, y2, COL_HINT); + x1++, y1++, x2--, y2--; + } + } + unclip(fe); draw_update(fe, bx+1, by+1, TILE_SIZE-1, TILE_SIZE-1); @@ -879,10 +1139,13 @@ static void game_redraw(frontend *fe, game_drawstate *ds, game_state *oldstate, else flashframe = -1; + animtime /= ANIM_TIME; /* scale it so it goes from 0 to 1 */ + for (i = 0; i < wh; i++) { int x = i % w, y = i / w; int fx, fy, fd; int v = state->grid[i]; + int vv; if (flashframe >= 0) { fx = (w+1)/2 - min(x+1, w-x); @@ -893,17 +1156,28 @@ static void game_redraw(frontend *fe, game_drawstate *ds, game_state *oldstate, else if (fd == flashframe - 1) v &= ~1; } - - if (ds->tiles[i] != v) { - draw_tile(fe, ds, state, x, y, v); - ds->tiles[i] = v; + + if (!state->hints_active) + v &= ~2; + + if (oldstate && state->grid[i] != oldstate->grid[i]) + vv = 255; /* means `animated' */ + else + vv = v; + + if (ds->tiles[i] == 255 || vv == 255 || ds->tiles[i] != vv) { + draw_tile(fe, ds, state, x, y, v, vv == 255, animtime); + ds->tiles[i] = vv; } } { char buf[256]; - sprintf(buf, "%sMoves: %d", state->completed ? "COMPLETED! " : "", + sprintf(buf, "%sMoves: %d", + (state->completed ? + (state->cheated ? "Auto-solved. " : "COMPLETED! ") : + (state->cheated ? "Auto-solver used. " : "")), state->moves); status_bar(fe, buf); @@ -913,7 +1187,7 @@ static void game_redraw(frontend *fe, game_drawstate *ds, game_state *oldstate, static float game_anim_length(game_state *oldstate, game_state *newstate, int dir, game_ui *ui) { - return 0.0F; + return ANIM_TIME; } static float game_flash_length(game_state *oldstate, game_state *newstate, @@ -940,7 +1214,7 @@ static int game_timing_state(game_state *state) #endif const struct game thegame = { - "Flip", NULL, + "Flip", "games.flip", default_params, game_fetch_preset, decode_params, @@ -950,17 +1224,19 @@ const struct game thegame = { TRUE, game_configure, custom_params, validate_params, new_game_desc, - game_free_aux_info, validate_desc, new_game, dup_game, free_game, - FALSE, solve_game, + TRUE, solve_game, FALSE, game_text_format, new_ui, free_ui, + encode_ui, + decode_ui, game_changed_state, - make_move, + interpret_move, + execute_move, game_size, game_colours, game_new_drawstate,