From ac511ec9c1cd34babf973d3615abd30169c11050 Mon Sep 17 00:00:00 2001 From: simon Date: Mon, 7 May 2007 14:49:05 +0000 Subject: [PATCH] Close-to-finished auto-generating implementation of Klotski. git-svn-id: svn://svn.tartarus.org/sgt/puzzles@7547 cda61777-01e9-0310-a592-d414129be87e --- unfinished/slide.R | 21 + unfinished/slide.c | 1916 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 1937 insertions(+) create mode 100644 unfinished/slide.R create mode 100644 unfinished/slide.c diff --git a/unfinished/slide.R b/unfinished/slide.R new file mode 100644 index 0000000..c6df86c --- /dev/null +++ b/unfinished/slide.R @@ -0,0 +1,21 @@ +# -*- makefile -*- + +SLIDE = slide dsf tree234 + +slide : [X] GTK COMMON SLIDE slide-icon|no-icon + +slide : [G] WINDOWS COMMON SLIDE slide.res|noicon.res + +ALL += SLIDE + +!begin gtk +GAMES += slide +!end + +!begin >list.c + A(slide) \ +!end + +!begin >wingames.lst +slide.exe:Slide +!end diff --git a/unfinished/slide.c b/unfinished/slide.c new file mode 100644 index 0000000..c9afe41 --- /dev/null +++ b/unfinished/slide.c @@ -0,0 +1,1916 @@ +/* + * slide.c: Implementation of the block-sliding puzzle `Klotski'. + */ + +/* + * TODO: + * + * - Solve function: + * * try to generate a solution when Solve is pressed + * + from the start, or from here? From here, I fear. + * + hence, not much point saving the solution in an aux + * string + * * Inertia-like method for telling the user the solution + * * standalone solver which draws diagrams + * + * - The dragging semantics are still subtly wrong in complex + * cases. + * + * - Improve the generator. + * + * - All the colours are a bit wishy-washy. _Some_ dark colours + * would surely not be excessive? Probably darken the tiles, + * the walls and the main block, and leave the target marker + * pale. + */ + +#include +#include +#include +#include +#include +#include + +#include "puzzles.h" +#include "tree234.h" + +/* + * The implementation of this game revolves around the insight + * which makes an exhaustive-search solver feasible: although + * there are many blocks which can be rearranged in many ways, any + * two blocks of the same shape are _indistinguishable_ and hence + * the number of _distinct_ board layouts is generally much + * smaller. So we adopt a representation for board layouts which + * is inherently canonical, i.e. there are no two distinct + * representations which encode indistinguishable layouts. + * + * The way we do this is to encode each square of the board, in + * the normal left-to-right top-to-bottom order, as being one of + * the following things: + * - the first square (in the given order) of a block (`anchor') + * - special case of the above: the anchor for the _main_ block + * (i.e. the one which the aim of the game is to get to the + * target position) + * - a subsequent square of a block whose previous square was N + * squares ago + * - an impassable wall + * + * (We also separately store data about which board positions are + * forcefields only passable by the main block. We can't encode + * that in the main board data, because then the main block would + * destroy forcefields as it went over them.) + * + * Hence, for example, a 2x2 square block would be encoded as + * ANCHOR, followed by DIST(1), and w-2 squares later on there + * would be DIST(w-1) followed by DIST(1). So if you start at the + * last of those squares, the DIST numbers give you a linked list + * pointing back through all the other squares in the same block. + * + * So the solver simply does a bfs over all reachable positions, + * encoding them in this format and storing them in a tree234 to + * ensure it doesn't ever revisit an already-analysed position. + */ + +enum { + /* + * The colours are arranged here so that every base colour is + * directly followed by its highlight colour and then its + * lowlight colour. Do not break this, or draw_tile() will get + * confused. + */ + COL_BACKGROUND, + COL_HIGHLIGHT, + COL_LOWLIGHT, + COL_DRAGGING, + COL_DRAGGING_HIGHLIGHT, + COL_DRAGGING_LOWLIGHT, + COL_MAIN, + COL_MAIN_HIGHLIGHT, + COL_MAIN_LOWLIGHT, + COL_MAIN_DRAGGING, + COL_MAIN_DRAGGING_HIGHLIGHT, + COL_MAIN_DRAGGING_LOWLIGHT, + COL_TARGET, + COL_TARGET_HIGHLIGHT, + COL_TARGET_LOWLIGHT, + NCOLOURS +}; + +/* + * Board layout is a simple array of bytes. Each byte holds: + */ +#define ANCHOR 255 /* top-left-most square of some piece */ +#define MAINANCHOR 254 /* anchor of _main_ piece */ +#define EMPTY 253 /* empty square */ +#define WALL 252 /* immovable wall */ +#define MAXDIST 251 +/* all other values indicate distance back to previous square of same block */ +#define ISDIST(x) ( (unsigned char)((x)-1) <= MAXDIST-1 ) +#define DIST(x) (x) +#define ISANCHOR(x) ( (x)==ANCHOR || (x)==MAINANCHOR ) +#define ISBLOCK(x) ( ISANCHOR(x) || ISDIST(x) ) + +/* + * MAXDIST is the largest DIST value we can encode. This must + * therefore also be the maximum puzzle width in theory (although + * solver running time will dictate a much smaller limit in + * practice). + */ +#define MAXWID MAXDIST + +struct game_params { + int w, h; +}; + +struct game_immutable_state { + int refcount; + unsigned char *forcefield; +}; + +struct game_state { + int w, h; + unsigned char *board; + int tx, ty; /* target coords for MAINANCHOR */ + int minmoves; /* for display only */ + int lastmoved, lastmoved_pos; /* for move counting */ + int movecount; + int completed; + struct game_immutable_state *imm; +}; + +static game_params *default_params(void) +{ + game_params *ret = snew(game_params); + + ret->w = 8; + ret->h = 6; + + return ret; +} + +static const struct game_params slide_presets[] = { + {6, 5}, + {7, 5}, + {7, 6}, + {8, 6}, +}; + +static int game_fetch_preset(int i, char **name, game_params **params) +{ + game_params *ret; + char str[80]; + + if (i < 0 || i >= lenof(slide_presets)) + return FALSE; + + ret = snew(game_params); + *ret = slide_presets[i]; + + sprintf(str, "%dx%d", ret->w, ret->h); + + *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 void decode_params(game_params *params, char const *string) +{ + params->w = params->h = atoi(string); + while (*string && isdigit((unsigned char)*string)) string++; + if (*string == 'x') { + string++; + params->h = atoi(string); + } +} + +static char *encode_params(game_params *params, int full) +{ + 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, int full) +{ + if (params->w > MAXWID) + return "Width must be at most " STR(MAXWID); + + if (params->w < 5) + return "Width must be at least 5"; + if (params->h < 4) + return "Height must be at least 4"; + + return NULL; +} + +static char *board_text_format(int w, int h, unsigned char *data, + unsigned char *forcefield) +{ + int wh = w*h; + int *dsf = snew_dsf(wh); + int i, x, y; + int retpos, retlen = (w*2+2)*(h*2+1)+1; + char *ret = snewn(retlen, char); + + for (i = 0; i < wh; i++) + if (ISDIST(data[i])) + dsf_merge(dsf, i - data[i], i); + retpos = 0; + for (y = 0; y < 2*h+1; y++) { + for (x = 0; x < 2*w+1; x++) { + int v; + int i = (y/2)*w+(x/2); + +#define dtype(i) (ISBLOCK(data[i]) ? \ + dsf_canonify(dsf, i) : data[i]) +#define dchar(t) ((t)==EMPTY ? ' ' : (t)==WALL ? '#' : \ + data[t] == MAINANCHOR ? '*' : '%') + + if (y % 2 && x % 2) { + int j = dtype(i); + v = dchar(j); + } else if (y % 2 && !(x % 2)) { + int j1 = (x > 0 ? dtype(i-1) : -1); + int j2 = (x < 2*w ? dtype(i) : -1); + if (j1 != j2) + v = '|'; + else + v = dchar(j1); + } else if (!(y % 2) && (x % 2)) { + int j1 = (y > 0 ? dtype(i-w) : -1); + int j2 = (y < 2*h ? dtype(i) : -1); + if (j1 != j2) + v = '-'; + else + v = dchar(j1); + } else { + int j1 = (x > 0 && y > 0 ? dtype(i-w-1) : -1); + int j2 = (x > 0 && y < 2*h ? dtype(i-1) : -1); + int j3 = (x < 2*w && y > 0 ? dtype(i-w) : -1); + int j4 = (x < 2*w && y < 2*h ? dtype(i) : -1); + if (j1 == j2 && j2 == j3 && j3 == j4) + v = dchar(j1); + else if (j1 == j2 && j3 == j4) + v = '|'; + else if (j1 == j3 && j2 == j4) + v = '-'; + else + v = '+'; + } + + assert(retpos < retlen); + ret[retpos++] = v; + } + assert(retpos < retlen); + ret[retpos++] = '\n'; + } + assert(retpos < retlen); + ret[retpos++] = '\0'; + assert(retpos == retlen); + + return ret; +} + +/* ---------------------------------------------------------------------- + * Solver. + */ + +/* + * During solver execution, the set of visited board positions is + * stored as a tree234 of the following structures. `w', `h' and + * `data' are obvious in meaning; `dist' represents the minimum + * distance to reach this position from the starting point. + * + * `prev' links each board to the board position from which it was + * most efficiently derived. + */ +struct board { + int w, h; + int dist; + struct board *prev; + unsigned char *data; +}; + +static int boardcmp(void *av, void *bv) +{ + struct board *a = (struct board *)av; + struct board *b = (struct board *)bv; + return memcmp(a->data, b->data, a->w * a->h); +} + +static struct board *newboard(int w, int h, unsigned char *data) +{ + struct board *b = malloc(sizeof(struct board) + w*h); + b->data = (unsigned char *)b + sizeof(struct board); + memcpy(b->data, data, w*h); + b->w = w; + b->h = h; + b->dist = -1; + b->prev = NULL; + return b; +} + +/* + * The actual solver. Given a board, attempt to find the minimum + * length of move sequence which moves MAINANCHOR to (tx,ty), or + * -1 if no solution exists. Returns that minimum length, and + * (FIXME) optionally also writes out the actual moves into an + * as-yet-unprovided parameter. + */ +static int solve_board(int w, int h, unsigned char *board, + unsigned char *forcefield, int tx, int ty) +{ + int wh = w*h; + struct board *b, *b2, *b3; + int *next, *anchors, *which; + int *movereached, *movequeue, mqhead, mqtail; + tree234 *sorted, *queue; + int i, j, dir; + int qlen, lastdist; + int ret; + +#ifdef SOLVER_DIAGNOSTICS + { + char *t = board_text_format(w, h, board); + for (i = 0; i < h; i++) { + for (j = 0; j < w; j++) { + int c = board[i*w+j]; + if (ISDIST(c)) + printf("D%-3d", c); + else if (c == MAINANCHOR) + printf("M "); + else if (c == ANCHOR) + printf("A "); + else if (c == WALL) + printf("W "); + else if (c == EMPTY) + printf("E "); + } + printf("\n"); + } + + printf("Starting solver for:\n%s\n", t); + sfree(t); + } +#endif + + sorted = newtree234(boardcmp); + queue = newtree234(NULL); + + b = newboard(w, h, board); + b->dist = 0; + add234(sorted, b); + addpos234(queue, b, 0); + qlen = 1; + + next = snewn(wh, int); + anchors = snewn(wh, int); + which = snewn(wh, int); + movereached = snewn(wh, int); + movequeue = snewn(wh, int); + lastdist = -1; + + while ((b = delpos234(queue, 0)) != NULL) { + qlen--; + if (b->dist != lastdist) { +#ifdef SOLVER_DIAGNOSTICS + printf("dist %d (%d)\n", b->dist, count234(sorted)); +#endif + lastdist = b->dist; + } + /* + * Find all the anchors and form a linked list of the + * squares within each block. + */ + for (i = 0; i < wh; i++) { + next[i] = -1; + anchors[i] = FALSE; + which[i] = -1; + if (ISANCHOR(b->data[i])) { + anchors[i] = TRUE; + which[i] = i; + } else if (ISDIST(b->data[i])) { + j = i - b->data[i]; + next[j] = i; + which[i] = which[j]; + } + } + + /* + * For each anchor, do an array-based BFS to find all the + * places we can slide it to. + */ + for (i = 0; i < wh; i++) { + if (!anchors[i]) + continue; + + mqhead = mqtail = 0; + for (j = 0; j < wh; j++) + movereached[j] = FALSE; + movequeue[mqtail++] = i; + while (mqhead < mqtail) { + int pos = movequeue[mqhead++]; + + /* + * Try to move in each direction from here. + */ + for (dir = 0; dir < 4; dir++) { + int dx = (dir == 0 ? -1 : dir == 1 ? +1 : 0); + int dy = (dir == 2 ? -1 : dir == 3 ? +1 : 0); + int offset = dy*w + dx; + int newpos = pos + offset; + int d = newpos - i; + + /* + * For each square involved in this block, + * check to see if the square d spaces away + * from it is either empty or part of the same + * block. + */ + for (j = i; j >= 0; j = next[j]) { + int jy = (pos+j-i) / w + dy, jx = (pos+j-i) % w + dx; + if (jy >= 0 && jy < h && jx >= 0 && jx < w && + ((b->data[j+d] == EMPTY || which[j+d] == i) && + (b->data[i] == MAINANCHOR || !forcefield[j+d]))) + /* ok */; + else + break; + } + if (j >= 0) + continue; /* this direction wasn't feasible */ + + /* + * If we've already tried moving this piece + * here, leave it. + */ + if (movereached[newpos]) + continue; + movereached[newpos] = TRUE; + movequeue[mqtail++] = newpos; + + /* + * We have a viable move. Make it. + */ + b2 = newboard(w, h, b->data); + for (j = i; j >= 0; j = next[j]) + b2->data[j] = EMPTY; + for (j = i; j >= 0; j = next[j]) + b2->data[j+d] = b->data[j]; + + b3 = add234(sorted, b2); + if (b3 != b2) { + sfree(b2); /* we already got one */ + } else { + b2->dist = b->dist + 1; + b2->prev = b; + addpos234(queue, b2, qlen++); + if (b2->data[ty*w+tx] == MAINANCHOR) + goto done; /* search completed! */ + } + } + } + } + } + b2 = NULL; + + done: + + if (b2) + ret = b2->dist; + else + ret = -1; /* no solution */ + + freetree234(queue); + + while ((b = delpos234(sorted, 0)) != NULL) + sfree(b); + freetree234(sorted); + + sfree(next); + sfree(anchors); + sfree(movereached); + sfree(movequeue); + sfree(which); + + return ret; +} + +/* ---------------------------------------------------------------------- + * Random board generation. + */ + +static void generate_board(int w, int h, int *rtx, int *rty, int *minmoves, + random_state *rs, unsigned char **rboard, + unsigned char **rforcefield) +{ + int wh = w*h; + unsigned char *board, *board2, *forcefield; + int *list, nlist, pos; + int tx, ty; + int i, j; + int moves; + + /* + * Set up a board and fill it with singletons, except for a + * border of walls. + */ + board = snewn(wh, unsigned char); + forcefield = snewn(wh, unsigned char); + board2 = snewn(wh, unsigned char); + memset(board, ANCHOR, wh); + memset(forcefield, FALSE, wh); + for (i = 0; i < w; i++) + board[i] = board[i+w*(h-1)] = WALL; + for (i = 0; i < h; i++) + board[i*w] = board[i*w+(w-1)] = WALL; + + /* + * Invent a main piece at one extreme. (FIXME: vary the + * extreme, and the piece.) + */ + board[w+1] = MAINANCHOR; + board[w+2] = DIST(1); + board[w*2+1] = DIST(w-1); + board[w*2+2] = DIST(1); + + /* + * Invent a target position. (FIXME: vary this too.) + */ + tx = w-2; + ty = h-3; + forcefield[ty*w+tx+1] = forcefield[(ty+1)*w+tx+1] = TRUE; + board[ty*w+tx+1] = board[(ty+1)*w+tx+1] = EMPTY; + + /* + * Gradually remove singletons until the game becomes soluble. + */ + for (j = w; j-- > 0 ;) + for (i = h; i-- > 0 ;) + if (board[i*w+j] == ANCHOR) { + /* + * See if the board is already soluble. + */ + if ((moves = solve_board(w, h, board, forcefield, + tx, ty)) >= 0) + goto soluble; + + /* + * Otherwise, remove this piece. + */ + board[i*w+j] = EMPTY; + } + assert(!"We shouldn't get here"); + soluble: + + /* + * Make a list of all the inter-block edges on the board. + */ + list = snewn(wh*2, int); + nlist = 0; + for (i = 0; i+1 < w; i++) + for (j = 0; j < h; j++) + list[nlist++] = (j*w+i) * 2 + 0; /* edge to the right of j*w+i */ + for (j = 0; j+1 < h; j++) + for (i = 0; i < w; i++) + list[nlist++] = (j*w+i) * 2 + 1; /* edge below j*w+i */ + + /* + * Now go through that list in random order, trying to merge + * the blocks on each side of each edge. + * + * FIXME: this seems to produce unpleasantly unbalanced + * results. Perhaps we'd do better if we always tried to + * combine the _smallest_ block with something? + * + * FIXME: also one reason it's slow might be because we aren't + * tracking which blocks we've already tried to merge, when + * another edge ends up linking the same ones. + */ + shuffle(list, nlist, sizeof(*list), rs); + while (nlist > 0) { + int x1, y1, p1; + int x2, y2, p2; + + pos = list[--nlist]; + y1 = y2 = pos / (w*2); + x1 = x2 = (pos / 2) % w; + if (pos % 2) + y2++; + else + x2++; + p1 = y1*w+x1; + p2 = y2*w+x2; + + /* + * In order to be mergeable, these two squares must each + * either be, or belong to, a non-main anchor, and their + * anchors must also be distinct. + */ + if (!ISBLOCK(board[p1]) || !ISBLOCK(board[p2])) + continue; + while (ISDIST(board[p1])) + p1 -= board[p1]; + while (ISDIST(board[p2])) + p2 -= board[p2]; + if (board[p1] == MAINANCHOR || board[p2] == MAINANCHOR || p1 == p2) + continue; + + /* + * We can merge these blocks. Try it, and see if the + * puzzle remains soluble. + */ + memcpy(board2, board, wh); + j = -1; + while (p1 < wh || p2 < wh) { + /* + * p1 and p2 are the squares at the head of each block + * list. Pick the smaller one and put it on the output + * block list. + */ + i = min(p1, p2); + if (j < 0) { + board[i] = ANCHOR; + } else { + assert(i - j <= MAXDIST); + board[i] = DIST(i - j); + } + j = i; + + /* + * Now advance whichever list that came from. + */ + if (i == p1) { + do { + p1++; + } while (p1 < wh && board[p1] != DIST(p1-i)); + } else { + do { + p2++; + } while (p2 < wh && board[p2] != DIST(p2-i)); + } + } + j = solve_board(w, h, board, forcefield, tx, ty); + if (j < 0) { + /* + * Didn't work. Revert the merge. + */ + memcpy(board, board2, wh); + } else { + moves = j; + } + } + + sfree(board2); + + *rtx = tx; + *rty = ty; + *rboard = board; + *rforcefield = forcefield; + *minmoves = moves; +} + +/* ---------------------------------------------------------------------- + * End of solver/generator code. + */ + +static char *new_game_desc(game_params *params, random_state *rs, + char **aux, int interactive) +{ + int w = params->w, h = params->h, wh = w*h; + int tx, ty, minmoves; + unsigned char *board, *forcefield; + char *ret, *p; + int i; + + generate_board(params->w, params->h, &tx, &ty, &minmoves, rs, + &board, &forcefield); +#ifdef GENERATOR_DIAGNOSTICS + { + char *t = board_text_format(params->w, params->h, board); + printf("%s\n", t); + sfree(t); + } +#endif + + /* + * Encode as a game ID. + */ + ret = snewn(wh * 6 + 40, char); + p = ret; + i = 0; + while (i < wh) { + if (ISDIST(board[i])) { + p += sprintf(p, "d%d", board[i]); + i++; + } else { + int count = 1; + int b = board[i], f = forcefield[i]; + int c = (b == ANCHOR ? 'a' : + b == MAINANCHOR ? 'm' : + b == EMPTY ? 'e' : + /* b == WALL ? */ 'w'); + if (f) *p++ = 'f'; + *p++ = c; + i++; + while (i < wh && board[i] == b && forcefield[i] == f) + i++, count++; + if (count > 1) + p += sprintf(p, "%d", count); + } + } + p += sprintf(p, ",%d,%d,%d", tx, ty, minmoves); + ret = sresize(ret, p+1 - ret, char); + + /* + * FIXME: generate an aux string + */ + + sfree(board); + sfree(forcefield); + + return ret; +} + +static char *validate_desc(game_params *params, char *desc) +{ + int w = params->w, h = params->h, wh = w*h; + int *active, *link; + int mains = 0, mpos = -1; + int i, j, tx, ty, minmoves; + char *ret; + + active = snewn(wh, int); + link = snewn(wh, int); + i = 0; + + while (*desc && *desc != ',') { + if (i >= wh) { + ret = "Too much data in game description"; + goto done; + } + link[i] = -1; + active[i] = FALSE; + if (*desc == 'f' || *desc == 'F') { + desc++; + if (!*desc) { + ret = "Expected another character after 'f' in game " + "description"; + goto done; + } + } + + if (*desc == 'd' || *desc == 'D') { + int dist; + + desc++; + if (!isdigit((unsigned char)*desc)) { + ret = "Expected a number after 'd' in game description"; + goto done; + } + dist = atoi(desc); + while (*desc && isdigit((unsigned char)*desc)) desc++; + + if (dist <= 0 || dist > i) { + ret = "Out-of-range number after 'd' in game description"; + goto done; + } + + if (!active[i - dist]) { + ret = "Invalid back-reference in game description"; + goto done; + } + + link[i] = i - dist; + for (j = i; j > 0; j = link[j]) + if (j == i-1 || j == i-w) + break; + if (j < 0) { + ret = "Disconnected piece in game description"; + goto done; + } + + active[i] = TRUE; + active[link[i]] = FALSE; + i++; + } else { + int c = *desc++; + int count = 1; + + if (!strchr("aAmMeEwW", c)) { + ret = "Invalid character in game description"; + goto done; + } + if (isdigit((unsigned char)*desc)) { + count = atoi(desc); + while (*desc && isdigit((unsigned char)*desc)) desc++; + } + if (i + count > wh) { + ret = "Too much data in game description"; + goto done; + } + while (count-- > 0) { + active[i] = (strchr("aAmM", c) != NULL); + link[i] = -1; + if (strchr("mM", c) != NULL) { + mains++; + mpos = i; + } + i++; + } + } + } + if (mains != 1) { + ret = (mains == 0 ? "No main piece specified in game description" : + "More than one main piece specified in game description"); + goto done; + } + if (i < wh) { + ret = "Not enough data in game description"; + goto done; + } + + /* + * Now read the target coordinates. + */ + i = sscanf(desc, ",%d,%d,%d", &tx, &ty, &minmoves); + if (i < 2) { + ret = "No target coordinates specified"; + goto done; + /* + * (but minmoves is optional) + */ + } + + ret = NULL; + + done: + sfree(active); + sfree(link); + return ret; +} + +static game_state *new_game(midend *me, game_params *params, char *desc) +{ + int w = params->w, h = params->h, wh = w*h; + game_state *state; + int i; + + state = snew(game_state); + state->w = w; + state->h = h; + state->board = snewn(wh, unsigned char); + state->lastmoved = state->lastmoved_pos = -1; + state->movecount = 0; + state->imm = snew(struct game_immutable_state); + state->imm->refcount = 1; + state->imm->forcefield = snewn(wh, unsigned char); + + i = 0; + + while (*desc && *desc != ',') { + int f = FALSE; + + assert(i < wh); + + if (*desc == 'f') { + f = TRUE; + desc++; + assert(*desc); + } + + if (*desc == 'd' || *desc == 'D') { + int dist; + + desc++; + dist = atoi(desc); + while (*desc && isdigit((unsigned char)*desc)) desc++; + + state->board[i] = DIST(dist); + state->imm->forcefield[i] = f; + + i++; + } else { + int c = *desc++; + int count = 1; + + if (isdigit((unsigned char)*desc)) { + count = atoi(desc); + while (*desc && isdigit((unsigned char)*desc)) desc++; + } + assert(i + count <= wh); + + c = (c == 'a' || c == 'A' ? ANCHOR : + c == 'm' || c == 'M' ? MAINANCHOR : + c == 'e' || c == 'E' ? EMPTY : + /* c == 'w' || c == 'W' ? */ WALL); + + while (count-- > 0) { + state->board[i] = c; + state->imm->forcefield[i] = f; + i++; + } + } + } + + /* + * Now read the target coordinates. + */ + state->tx = state->ty = 0; + state->minmoves = -1; + i = sscanf(desc, ",%d,%d,%d", &state->tx, &state->ty, &state->minmoves); + + if (state->board[state->ty*w+state->tx] == MAINANCHOR) + state->completed = 0; /* already complete! */ + else + state->completed = -1; + + return state; +} + +static game_state *dup_game(game_state *state) +{ + int w = state->w, h = state->h, wh = w*h; + game_state *ret = snew(game_state); + + ret->w = state->w; + ret->h = state->h; + ret->board = snewn(wh, unsigned char); + memcpy(ret->board, state->board, wh); + ret->tx = state->tx; + ret->ty = state->ty; + ret->minmoves = state->minmoves; + ret->lastmoved = state->lastmoved; + ret->lastmoved_pos = state->lastmoved_pos; + ret->movecount = state->movecount; + ret->completed = state->completed; + ret->imm = state->imm; + ret->imm->refcount++; + + return ret; +} + +static void free_game(game_state *state) +{ + if (--state->imm->refcount <= 0) { + sfree(state->imm->forcefield); + sfree(state->imm); + } + sfree(state->board); + sfree(state); +} + +static char *solve_game(game_state *state, game_state *currstate, + char *aux, char **error) +{ + /* + * FIXME: we have a solver, so use it + * + * FIXME: we should have generated an aux string, so use that + */ + return NULL; +} + +static char *game_text_format(game_state *state) +{ + return board_text_format(state->w, state->h, state->board, + state->imm->forcefield); +} + +struct game_ui { + int dragging; + int drag_anchor; + int drag_offset_x, drag_offset_y; + int drag_currpos; + unsigned char *reachable; + int *bfs_queue; /* used as scratch in interpret_move */ +}; + +static game_ui *new_ui(game_state *state) +{ + int w = state->w, h = state->h, wh = w*h; + game_ui *ui = snew(game_ui); + + ui->dragging = FALSE; + ui->drag_anchor = ui->drag_currpos = -1; + ui->drag_offset_x = ui->drag_offset_y = -1; + ui->reachable = snewn(wh, unsigned char); + memset(ui->reachable, 0, wh); + ui->bfs_queue = snewn(wh, int); + + return ui; +} + +static void free_ui(game_ui *ui) +{ + sfree(ui->bfs_queue); + sfree(ui->reachable); + sfree(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) +{ +} + +#define PREFERRED_TILESIZE 32 +#define TILESIZE (ds->tilesize) +#define BORDER (TILESIZE/2) +#define COORD(x) ( (x) * TILESIZE + BORDER ) +#define FROMCOORD(x) ( ((x) - BORDER + TILESIZE) / TILESIZE - 1 ) +#define BORDER_WIDTH (1 + TILESIZE/20) +#define HIGHLIGHT_WIDTH (1 + TILESIZE/16) + +#define FLASH_INTERVAL 0.10F +#define FLASH_TIME 3*FLASH_INTERVAL + +struct game_drawstate { + int tilesize; + int w, h; + unsigned long *grid; /* what's currently displayed */ + int started; +}; + +static char *interpret_move(game_state *state, game_ui *ui, game_drawstate *ds, + int x, int y, int button) +{ + int w = state->w, h = state->h, wh = w*h; + int tx, ty, i, j; + int qhead, qtail; + + if (button == LEFT_BUTTON) { + tx = FROMCOORD(x); + ty = FROMCOORD(y); + + if (tx < 0 || tx >= w || ty < 0 || ty >= h || + !ISBLOCK(state->board[ty*w+tx])) + return NULL; /* this click has no effect */ + + /* + * User has clicked on a block. Find the block's anchor + * and register that we've started dragging it. + */ + i = ty*w+tx; + while (ISDIST(state->board[i])) + i -= state->board[i]; + assert(i >= 0 && i < wh); + + ui->dragging = TRUE; + ui->drag_anchor = i; + ui->drag_offset_x = tx - (i % w); + ui->drag_offset_y = ty - (i / w); + ui->drag_currpos = i; + + /* + * Now we immediately bfs out from the current location of + * the anchor, to find all the places to which this block + * can be dragged. + */ + memset(ui->reachable, FALSE, wh); + qhead = qtail = 0; + ui->reachable[i] = TRUE; + ui->bfs_queue[qtail++] = i; + for (j = i; j < wh; j++) + if (state->board[j] == DIST(j - i)) + i = j; + while (qhead < qtail) { + int pos = ui->bfs_queue[qhead++]; + int x = pos % w, y = pos / w; + int dir; + + for (dir = 0; dir < 4; dir++) { + int dx = (dir == 0 ? -1 : dir == 1 ? +1 : 0); + int dy = (dir == 2 ? -1 : dir == 3 ? +1 : 0); + int newpos; + + if (x + dx < 0 || x + dx >= w || + y + dy < 0 || y + dy >= h) + continue; + + newpos = pos + dy*w + dx; + if (ui->reachable[newpos]) + continue; /* already done this one */ + + /* + * Now search the grid to see if the block we're + * dragging could fit into this space. + */ + for (j = i; j >= 0; j = (ISDIST(state->board[j]) ? + j - state->board[j] : -1)) { + int jx = (j+pos-ui->drag_anchor) % w; + int jy = (j+pos-ui->drag_anchor) / w; + int j2; + + if (jx + dx < 0 || jx + dx >= w || + jy + dy < 0 || jy + dy >= h) + break; /* this position isn't valid at all */ + + j2 = (j+pos-ui->drag_anchor) + dy*w + dx; + + if (state->board[j2] == EMPTY && + (!state->imm->forcefield[j2] || + state->board[ui->drag_anchor] == MAINANCHOR)) + continue; + while (ISDIST(state->board[j2])) + j2 -= state->board[j2]; + assert(j2 >= 0 && j2 < wh); + if (j2 == ui->drag_anchor) + continue; + else + break; + } + + if (j < 0) { + /* + * If we got to the end of that loop without + * disqualifying this position, mark it as + * reachable for this drag. + */ + ui->reachable[newpos] = TRUE; + ui->bfs_queue[qtail++] = newpos; + } + } + } + + /* + * And that's it. Update the display to reflect the start + * of a drag. + */ + return ""; + } else if (button == LEFT_DRAG && ui->dragging) { + tx = FROMCOORD(x); + ty = FROMCOORD(y); + + tx -= ui->drag_offset_x; + ty -= ui->drag_offset_y; + if (tx < 0 || tx >= w || ty < 0 || ty >= h || + !ui->reachable[ty*w+tx]) + return NULL; /* this drag has no effect */ + + ui->drag_currpos = ty*w+tx; + return ""; + } else if (button == LEFT_RELEASE && ui->dragging) { + char data[256], *str; + + /* + * Terminate the drag, and if the piece has actually moved + * then return a move string quoting the old and new + * locations of the piece's anchor. + */ + if (ui->drag_anchor != ui->drag_currpos) { + sprintf(data, "M%d-%d", ui->drag_anchor, ui->drag_currpos); + str = dupstr(data); + } else + str = ""; /* null move; just update the UI */ + + ui->dragging = FALSE; + ui->drag_anchor = ui->drag_currpos = -1; + ui->drag_offset_x = ui->drag_offset_y = -1; + memset(ui->reachable, 0, wh); + + return str; + } + + return NULL; +} + +static int move_piece(int w, int h, const unsigned char *src, + unsigned char *dst, unsigned char *ff, int from, int to) +{ + int wh = w*h; + int i, j; + + if (!ISANCHOR(dst[from])) + return FALSE; + + /* + * Scan to the far end of the piece's linked list. + */ + for (i = j = from; j < wh; j++) + if (src[j] == DIST(j - i)) + i = j; + + /* + * Remove the piece from its old location in the new + * game state. + */ + for (j = i; j >= 0; j = (ISDIST(src[j]) ? j - src[j] : -1)) + dst[j] = EMPTY; + + /* + * And put it back in at the new location. + */ + for (j = i; j >= 0; j = (ISDIST(src[j]) ? j - src[j] : -1)) { + int jn = j + to - from; + if (jn < 0 || jn >= wh) + return FALSE; + if (dst[jn] == EMPTY && (!ff[jn] || src[from] == MAINANCHOR)) { + dst[jn] = src[j]; + } else { + return FALSE; + } + } + + return TRUE; +} + +static game_state *execute_move(game_state *state, char *move) +{ + int w = state->w, h = state->h /* , wh = w*h */; + char c; + int a1, a2, n; + game_state *ret = dup_game(state); + + while (*move) { + c = *move; + if (c == 'M') { + move++; + if (sscanf(move, "%d-%d%n", &a1, &a2, &n) != 2 || + !move_piece(w, h, state->board, ret->board, + state->imm->forcefield, a1, a2)) { + free_game(ret); + return NULL; + } + if (a1 == ret->lastmoved) { + /* + * If the player has moved the same piece as they + * moved last time, don't increment the move + * count. In fact, if they've put the piece back + * where it started from, _decrement_ the move + * count. + */ + if (a2 == ret->lastmoved_pos) { + ret->movecount--; /* reverted last move */ + ret->lastmoved = ret->lastmoved_pos = -1; + } else { + ret->lastmoved = a2; + /* don't change lastmoved_pos */ + } + } else { + ret->lastmoved = a2; + ret->lastmoved_pos = a1; + ret->movecount++; + } + if (ret->board[a2] == MAINANCHOR && + a2 == ret->ty * w + ret->tx && ret->completed < 0) + ret->completed = ret->movecount; + move += n; + } else { + free_game(ret); + return NULL; + } + if (*move == ';') + move++; + else if (*move) { + free_game(ret); + return NULL; + } + } + + return ret; +} + +/* ---------------------------------------------------------------------- + * Drawing routines. + */ + +static void game_compute_size(game_params *params, int tilesize, + int *x, int *y) +{ + /* fool the macros */ + struct dummy { int tilesize; } dummy = { tilesize }, *ds = &dummy; + + *x = params->w * TILESIZE + 2*BORDER; + *y = params->h * TILESIZE + 2*BORDER; +} + +static void game_set_size(drawing *dr, game_drawstate *ds, + game_params *params, int tilesize) +{ + ds->tilesize = tilesize; +} + +static void raise_colour(float *target, float *src, float *limit) +{ + int i; + for (i = 0; i < 3; i++) + target[i] = (2*src[i] + limit[i]) / 3; +} + +static float *game_colours(frontend *fe, int *ncolours) +{ + float *ret = snewn(3 * NCOLOURS, float); + + game_mkhighlight(fe, ret, COL_BACKGROUND, COL_HIGHLIGHT, COL_LOWLIGHT); + + /* + * When dragging a tile, we light it up a bit. + */ + raise_colour(ret+3*COL_DRAGGING, + ret+3*COL_BACKGROUND, ret+3*COL_HIGHLIGHT); + raise_colour(ret+3*COL_DRAGGING_HIGHLIGHT, + ret+3*COL_HIGHLIGHT, ret+3*COL_HIGHLIGHT); + raise_colour(ret+3*COL_DRAGGING_LOWLIGHT, + ret+3*COL_LOWLIGHT, ret+3*COL_HIGHLIGHT); + + /* + * The main tile is tinted blue. + */ + ret[COL_MAIN * 3 + 0] = ret[COL_BACKGROUND * 3 + 0]; + ret[COL_MAIN * 3 + 1] = ret[COL_BACKGROUND * 3 + 1]; + ret[COL_MAIN * 3 + 2] = ret[COL_HIGHLIGHT * 3 + 2]; + game_mkhighlight_specific(fe, ret, COL_MAIN, + COL_MAIN_HIGHLIGHT, COL_MAIN_LOWLIGHT); + + /* + * And we light that up a bit too when dragging. + */ + raise_colour(ret+3*COL_MAIN_DRAGGING, + ret+3*COL_MAIN, ret+3*COL_MAIN_HIGHLIGHT); + raise_colour(ret+3*COL_MAIN_DRAGGING_HIGHLIGHT, + ret+3*COL_MAIN_HIGHLIGHT, ret+3*COL_MAIN_HIGHLIGHT); + raise_colour(ret+3*COL_MAIN_DRAGGING_LOWLIGHT, + ret+3*COL_MAIN_LOWLIGHT, ret+3*COL_MAIN_HIGHLIGHT); + + /* + * The target area on the floor is tinted green. + */ + ret[COL_TARGET * 3 + 0] = ret[COL_BACKGROUND * 3 + 0]; + ret[COL_TARGET * 3 + 1] = ret[COL_HIGHLIGHT * 3 + 1]; + ret[COL_TARGET * 3 + 2] = ret[COL_BACKGROUND * 3 + 2]; + game_mkhighlight_specific(fe, ret, COL_TARGET, + COL_TARGET_HIGHLIGHT, COL_TARGET_LOWLIGHT); + + *ncolours = NCOLOURS; + return ret; +} + +static game_drawstate *game_new_drawstate(drawing *dr, game_state *state) +{ + int w = state->w, h = state->h, wh = w*h; + struct game_drawstate *ds = snew(struct game_drawstate); + int i; + + ds->tilesize = 0; + ds->w = w; + ds->h = h; + ds->started = FALSE; + ds->grid = snewn(wh, unsigned long); + for (i = 0; i < wh; i++) + ds->grid[i] = ~(unsigned long)0; + + return ds; +} + +static void game_free_drawstate(drawing *dr, game_drawstate *ds) +{ + sfree(ds->grid); + sfree(ds); +} + +#define BG_NORMAL 0x00000001UL +#define BG_TARGET 0x00000002UL +#define BG_FORCEFIELD 0x00000004UL +#define FLASH_LOW 0x00000008UL +#define FLASH_HIGH 0x00000010UL +#define FG_WALL 0x00000020UL +#define FG_MAIN 0x00000040UL +#define FG_NORMAL 0x00000080UL +#define FG_DRAGGING 0x00000100UL +#define FG_LBORDER 0x00000200UL +#define FG_TBORDER 0x00000400UL +#define FG_RBORDER 0x00000800UL +#define FG_BBORDER 0x00001000UL +#define FG_TLCORNER 0x00002000UL +#define FG_TRCORNER 0x00004000UL +#define FG_BLCORNER 0x00008000UL +#define FG_BRCORNER 0x00010000UL + +/* + * Utility function. + */ +#define TYPE_MASK 0xF000 +#define COL_MASK 0x0FFF +#define TYPE_RECT 0x0000 +#define TYPE_TLCIRC 0x4000 +#define TYPE_TRCIRC 0x5000 +#define TYPE_BLCIRC 0x6000 +#define TYPE_BRCIRC 0x7000 +static void maybe_rect(drawing *dr, int x, int y, int w, int h, int coltype) +{ + int colour = coltype & COL_MASK, type = coltype & TYPE_MASK; + + if (colour > NCOLOURS) + return; + if (type == TYPE_RECT) { + draw_rect(dr, x, y, w, h, colour); + } else { + int cx, cy, r; + + clip(dr, x, y, w, h); + + cx = x; + cy = y; + assert(w == h); + r = w-1; + if (type & 0x1000) + cx += r; + if (type & 0x2000) + cy += r; + draw_circle(dr, cx, cy, r, colour, colour); + + unclip(dr); + } +} + +static void draw_tile(drawing *dr, game_drawstate *ds, + int x, int y, unsigned long val) +{ + int tx = COORD(x), ty = COORD(y); + int cc, ch, cl; + + /* + * Draw the tile background. + */ + if (val & BG_TARGET) + cc = COL_TARGET; + else + cc = COL_BACKGROUND; + ch = cc+1; + cl = cc+2; + if (val & FLASH_LOW) + cc = cl; + else if (val & FLASH_HIGH) + cc = ch; + + draw_rect(dr, tx, ty, TILESIZE, TILESIZE, cc); + if (val & BG_FORCEFIELD) { + /* + * Cattle-grid effect to indicate that nothing but the + * main block can slide over this square. + */ + int n = 3 * (TILESIZE / (3*HIGHLIGHT_WIDTH)); + int i; + + for (i = 1; i < n; i += 3) { + draw_rect(dr, tx,ty+(TILESIZE*i/n), TILESIZE,HIGHLIGHT_WIDTH, cl); + draw_rect(dr, tx+(TILESIZE*i/n),ty, HIGHLIGHT_WIDTH,TILESIZE, cl); + } + } + + /* + * Draw the tile foreground, i.e. some section of a block or + * wall. + */ + if (val & FG_WALL) { + cc = COL_BACKGROUND; + ch = cc+1; + cl = cc+2; + if (val & FLASH_LOW) + cc = cl; + else if (val & FLASH_HIGH) + cc = ch; + + draw_rect(dr, tx, ty, TILESIZE, TILESIZE, cc); + if (val & FG_LBORDER) + draw_rect(dr, tx, ty, HIGHLIGHT_WIDTH, TILESIZE, + ch); + if (val & FG_RBORDER) + draw_rect(dr, tx+TILESIZE-HIGHLIGHT_WIDTH, ty, + HIGHLIGHT_WIDTH, TILESIZE, cl); + if (val & FG_TBORDER) + draw_rect(dr, tx, ty, TILESIZE, HIGHLIGHT_WIDTH, ch); + if (val & FG_BBORDER) + draw_rect(dr, tx, ty+TILESIZE-HIGHLIGHT_WIDTH, + TILESIZE, HIGHLIGHT_WIDTH, cl); + if (!((FG_BBORDER | FG_LBORDER) &~ val)) + draw_rect(dr, tx, ty+TILESIZE-HIGHLIGHT_WIDTH, + HIGHLIGHT_WIDTH, HIGHLIGHT_WIDTH, cc); + if (!((FG_TBORDER | FG_RBORDER) &~ val)) + draw_rect(dr, tx+TILESIZE-HIGHLIGHT_WIDTH, ty, + HIGHLIGHT_WIDTH, HIGHLIGHT_WIDTH, cc); + if (val & FG_TLCORNER) + draw_rect(dr, tx, ty, HIGHLIGHT_WIDTH, HIGHLIGHT_WIDTH, ch); + if (val & FG_BRCORNER) + draw_rect(dr, tx+TILESIZE-HIGHLIGHT_WIDTH, + ty+TILESIZE-HIGHLIGHT_WIDTH, + HIGHLIGHT_WIDTH, HIGHLIGHT_WIDTH, cl); + } else if (val & (FG_MAIN | FG_NORMAL)) { + int x[6], y[6]; + + if (val & FG_DRAGGING) + cc = (val & FG_MAIN ? COL_MAIN_DRAGGING : COL_DRAGGING); + else + cc = (val & FG_MAIN ? COL_MAIN : COL_BACKGROUND); + ch = cc+1; + cl = cc+2; + + if (val & FLASH_LOW) + cc = cl; + else if (val & FLASH_HIGH) + cc = ch; + + /* + * Drawing the blocks is hellishly fiddly. The blocks + * don't stretch to the full size of the tile; there's a + * border around them of size BORDER_WIDTH. Then they have + * bevelled borders of size HIGHLIGHT_WIDTH, and also + * rounded corners. + * + * I tried for some time to find a clean and clever way to + * figure out what needed drawing from the corner and + * border flags, but in the end the cleanest way I could + * find was the following. We divide the grid square into + * 25 parts by ruling four horizontal and four vertical + * lines across it; those lines are at BORDER_WIDTH and + * BORDER_WIDTH+HIGHLIGHT_WIDTH from the top, from the + * bottom, from the left and from the right. Then we + * carefully consider each of the resulting 25 sections of + * square, and decide separately what needs to go in it + * based on the flags. In complicated cases there can be + * up to five possibilities affecting any given section + * (no corner or border flags, just the corner flag, one + * border flag, the other border flag, both border flags). + * So there's a lot of very fiddly logic here and all I + * could really think to do was give it my best shot and + * then test it and correct all the typos. Not fun to + * write, and I'm sure it isn't fun to read either, but it + * seems to work. + */ + + x[0] = tx; + x[1] = x[0] + BORDER_WIDTH; + x[2] = x[1] + HIGHLIGHT_WIDTH; + x[5] = tx + TILESIZE; + x[4] = x[5] - BORDER_WIDTH; + x[3] = x[4] - HIGHLIGHT_WIDTH; + + y[0] = ty; + y[1] = y[0] + BORDER_WIDTH; + y[2] = y[1] + HIGHLIGHT_WIDTH; + y[5] = ty + TILESIZE; + y[4] = y[5] - BORDER_WIDTH; + y[3] = y[4] - HIGHLIGHT_WIDTH; + +#define RECT(p,q) x[p], y[q], x[(p)+1]-x[p], y[(q)+1]-y[q] + + maybe_rect(dr, RECT(0,0), + (val & (FG_TLCORNER | FG_TBORDER | FG_LBORDER)) ? -1 : cc); + maybe_rect(dr, RECT(1,0), + (val & FG_TLCORNER) ? ch : (val & FG_TBORDER) ? -1 : + (val & FG_LBORDER) ? ch : cc); + maybe_rect(dr, RECT(2,0), + (val & FG_TBORDER) ? -1 : cc); + maybe_rect(dr, RECT(3,0), + (val & FG_TRCORNER) ? cl : (val & FG_TBORDER) ? -1 : + (val & FG_RBORDER) ? cl : cc); + maybe_rect(dr, RECT(4,0), + (val & (FG_TRCORNER | FG_TBORDER | FG_RBORDER)) ? -1 : cc); + maybe_rect(dr, RECT(0,1), + (val & FG_TLCORNER) ? ch : (val & FG_LBORDER) ? -1 : + (val & FG_TBORDER) ? ch : cc); + maybe_rect(dr, RECT(1,1), + (val & FG_TLCORNER) ? cc : -1); + maybe_rect(dr, RECT(1,1), + (val & FG_TLCORNER) ? ch | TYPE_TLCIRC : + !((FG_TBORDER | FG_LBORDER) &~ val) ? ch | TYPE_BRCIRC : + (val & (FG_TBORDER | FG_LBORDER)) ? ch : cc); + maybe_rect(dr, RECT(2,1), + (val & FG_TBORDER) ? ch : cc); + maybe_rect(dr, RECT(3,1), + (val & (FG_TBORDER | FG_RBORDER)) == FG_TBORDER ? ch : + (val & (FG_TBORDER | FG_RBORDER)) == FG_RBORDER ? cl : + !((FG_TBORDER|FG_RBORDER) &~ val) ? cc | TYPE_BLCIRC : cc); + maybe_rect(dr, RECT(4,1), + (val & FG_TRCORNER) ? ch : (val & FG_RBORDER) ? -1 : + (val & FG_TBORDER) ? ch : cc); + maybe_rect(dr, RECT(0,2), + (val & FG_LBORDER) ? -1 : cc); + maybe_rect(dr, RECT(1,2), + (val & FG_LBORDER) ? ch : cc); + maybe_rect(dr, RECT(2,2), + cc); + maybe_rect(dr, RECT(3,2), + (val & FG_RBORDER) ? cl : cc); + maybe_rect(dr, RECT(4,2), + (val & FG_RBORDER) ? -1 : cc); + maybe_rect(dr, RECT(0,3), + (val & FG_BLCORNER) ? cl : (val & FG_LBORDER) ? -1 : + (val & FG_BBORDER) ? cl : cc); + maybe_rect(dr, RECT(1,3), + (val & (FG_BBORDER | FG_LBORDER)) == FG_BBORDER ? cl : + (val & (FG_BBORDER | FG_LBORDER)) == FG_LBORDER ? ch : + !((FG_BBORDER|FG_LBORDER) &~ val) ? cc | TYPE_TRCIRC : cc); + maybe_rect(dr, RECT(2,3), + (val & FG_BBORDER) ? cl : cc); + maybe_rect(dr, RECT(3,3), + (val & FG_BRCORNER) ? cc : -1); + maybe_rect(dr, RECT(3,3), + (val & FG_BRCORNER) ? cl | TYPE_BRCIRC : + !((FG_BBORDER | FG_RBORDER) &~ val) ? cl | TYPE_TLCIRC : + (val & (FG_BBORDER | FG_RBORDER)) ? cl : cc); + maybe_rect(dr, RECT(4,3), + (val & FG_BRCORNER) ? cl : (val & FG_RBORDER) ? -1 : + (val & FG_BBORDER) ? cl : cc); + maybe_rect(dr, RECT(0,4), + (val & (FG_BLCORNER | FG_BBORDER | FG_LBORDER)) ? -1 : cc); + maybe_rect(dr, RECT(1,4), + (val & FG_BLCORNER) ? ch : (val & FG_BBORDER) ? -1 : + (val & FG_LBORDER) ? ch : cc); + maybe_rect(dr, RECT(2,4), + (val & FG_BBORDER) ? -1 : cc); + maybe_rect(dr, RECT(3,4), + (val & FG_BRCORNER) ? cl : (val & FG_BBORDER) ? -1 : + (val & FG_RBORDER) ? cl : cc); + maybe_rect(dr, RECT(4,4), + (val & (FG_BRCORNER | FG_BBORDER | FG_RBORDER)) ? -1 : cc); + +#undef RECT + + } + + draw_update(dr, tx, ty, TILESIZE, TILESIZE); +} + +static void game_redraw(drawing *dr, game_drawstate *ds, game_state *oldstate, + game_state *state, int dir, game_ui *ui, + float animtime, float flashtime) +{ + int w = state->w, h = state->h, wh = w*h; + unsigned char *board; + int *dsf; + int x, y, mainanchor, mainpos, dragpos; + + if (!ds->started) { + /* + * The initial contents of the window are not guaranteed + * and can vary with front ends. To be on the safe side, + * all games should start by drawing a big + * background-colour rectangle covering the whole window. + */ + draw_rect(dr, 0, 0, 10*ds->tilesize, 10*ds->tilesize, COL_BACKGROUND); + ds->started = TRUE; + } + + /* + * Construct the board we'll be displaying (which may be + * different from the one in state if ui describes a drag in + * progress). + */ + board = snewn(wh, unsigned char); + memcpy(board, state->board, wh); + if (ui->dragging) { + int mpret = move_piece(w, h, state->board, board, + state->imm->forcefield, + ui->drag_anchor, ui->drag_currpos); + assert(mpret); + } + + /* + * Build a dsf out of that board, so we can conveniently tell + * which edges are connected and which aren't. + */ + dsf = snew_dsf(wh); + mainanchor = -1; + for (y = 0; y < h; y++) + for (x = 0; x < w; x++) { + int i = y*w+x; + + if (ISDIST(board[i])) + dsf_merge(dsf, i, i - board[i]); + if (board[i] == MAINANCHOR) + mainanchor = i; + if (board[i] == WALL) { + if (x > 0 && board[i-1] == WALL) + dsf_merge(dsf, i, i-1); + if (y > 0 && board[i-w] == WALL) + dsf_merge(dsf, i, i-w); + } + } + assert(mainanchor >= 0); + mainpos = dsf_canonify(dsf, mainanchor); + dragpos = ui->drag_currpos > 0 ? dsf_canonify(dsf, ui->drag_currpos) : -1; + + /* + * Now we can construct the data about what we want to draw. + */ + for (y = 0; y < h; y++) + for (x = 0; x < w; x++) { + int i = y*w+x; + int j; + unsigned long val; + int canon; + + /* + * See if this square is part of the target area. + */ + j = i + mainanchor - (state->ty * w + state->tx); + while (j >= 0 && j < wh && ISDIST(board[j])) + j -= board[j]; + if (j == mainanchor) + val = BG_TARGET; + else + val = BG_NORMAL; + + if (state->imm->forcefield[i]) + val |= BG_FORCEFIELD; + + if (flashtime > 0) { + int flashtype = (int)(flashtime / FLASH_INTERVAL) & 1; + val |= (flashtype ? FLASH_LOW : FLASH_HIGH); + } + + if (board[i] != EMPTY) { + canon = dsf_canonify(dsf, i); + + if (board[i] == WALL) + val |= FG_WALL; + else if (canon == mainpos) + val |= FG_MAIN; + else + val |= FG_NORMAL; + if (canon == dragpos) + val |= FG_DRAGGING; + + /* + * Now look around to see if other squares + * belonging to the same block are adjacent to us. + */ + if (x == 0 || canon != dsf_canonify(dsf, i-1)) + val |= FG_LBORDER; + if (y== 0 || canon != dsf_canonify(dsf, i-w)) + val |= FG_TBORDER; + if (x == w-1 || canon != dsf_canonify(dsf, i+1)) + val |= FG_RBORDER; + if (y == h-1 || canon != dsf_canonify(dsf, i+w)) + val |= FG_BBORDER; + if (!(val & (FG_TBORDER | FG_LBORDER)) && + canon != dsf_canonify(dsf, i-1-w)) + val |= FG_TLCORNER; + if (!(val & (FG_TBORDER | FG_RBORDER)) && + canon != dsf_canonify(dsf, i+1-w)) + val |= FG_TRCORNER; + if (!(val & (FG_BBORDER | FG_LBORDER)) && + canon != dsf_canonify(dsf, i-1+w)) + val |= FG_BLCORNER; + if (!(val & (FG_BBORDER | FG_RBORDER)) && + canon != dsf_canonify(dsf, i+1+w)) + val |= FG_BRCORNER; + } + + if (val != ds->grid[i]) { + draw_tile(dr, ds, x, y, val); + ds->grid[i] = val; + } + } + + /* + * Update the status bar. + */ + { + char statusbuf[256]; + + /* + * FIXME: do something about auto-solve? + */ + sprintf(statusbuf, "%sMoves: %d", + (state->completed >= 0 ? "COMPLETED! " : ""), + (state->completed >= 0 ? state->completed : state->movecount)); + if (state->minmoves) + sprintf(statusbuf+strlen(statusbuf), " (min %d)", + state->minmoves); + + status_bar(dr, statusbuf); + } + + sfree(dsf); + sfree(board); +} + +static float game_anim_length(game_state *oldstate, game_state *newstate, + int dir, game_ui *ui) +{ + return 0.0F; +} + +static float game_flash_length(game_state *oldstate, game_state *newstate, + int dir, game_ui *ui) +{ + if (oldstate->completed < 0 && newstate->completed >= 0) + return FLASH_TIME; + + return 0.0F; +} + +static int game_timing_state(game_state *state, game_ui *ui) +{ + return TRUE; +} + +static void game_print_size(game_params *params, float *x, float *y) +{ +} + +static void game_print(drawing *dr, game_state *state, int tilesize) +{ +} + +#ifdef COMBINED +#define thegame nullgame +#endif + +const struct game thegame = { + "Slide", NULL, NULL, + default_params, + game_fetch_preset, + decode_params, + encode_params, + free_params, + dup_params, + TRUE, game_configure, custom_params, + validate_params, + new_game_desc, + validate_desc, + new_game, + dup_game, + free_game, + FALSE, solve_game, /* FIXME */ + TRUE, game_text_format, + new_ui, + free_ui, + encode_ui, + decode_ui, + game_changed_state, + interpret_move, + execute_move, + PREFERRED_TILESIZE, game_compute_size, game_set_size, + game_colours, + game_new_drawstate, + game_free_drawstate, + game_redraw, + game_anim_length, + game_flash_length, + FALSE, FALSE, game_print_size, game_print, + TRUE, /* wants_statusbar */ + FALSE, game_timing_state, + 0, /* flags */ +}; -- 2.11.0