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-rw-r--r--apps/plugins/puzzles/netslide.c1893
1 files changed, 1893 insertions, 0 deletions
diff --git a/apps/plugins/puzzles/netslide.c b/apps/plugins/puzzles/netslide.c
new file mode 100644
index 0000000000..e299b96eb3
--- /dev/null
+++ b/apps/plugins/puzzles/netslide.c
@@ -0,0 +1,1893 @@
+/*
+ * netslide.c: cross between Net and Sixteen, courtesy of Richard
+ * Boulton.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "rbassert.h"
+#include <ctype.h>
+#include <math.h>
+
+#include "puzzles.h"
+#include "tree234.h"
+
+#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 PREFERRED_TILE_SIZE 48
+#define TILE_SIZE (ds->tilesize)
+#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;
+ int movetarget;
+};
+
+struct game_state {
+ int width, height, cx, cy, wrapping, completed;
+ int used_solve;
+ int move_count, movetarget;
+
+ /* 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_col_int(int w, int h, unsigned char *tiles, int dir, int col);
+static void slide_row(game_state *state, int dir, int row);
+static void slide_row_int(int w, int h, unsigned char *tiles, 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;
+ ret->movetarget = 0;
+
+ return ret;
+}
+
+static const struct { int x, y, wrap, bprob; const char* desc; }
+netslide_presets[] = {
+ {3, 3, FALSE, 1, " easy"},
+ {3, 3, FALSE, 0, " medium"},
+ {3, 3, TRUE, 0, " hard"},
+ {4, 4, FALSE, 1, " easy"},
+ {4, 4, FALSE, 0, " medium"},
+ {4, 4, TRUE, 0, " hard"},
+ {5, 5, FALSE, 1, " easy"},
+ {5, 5, FALSE, 0, " medium"},
+ {5, 5, TRUE, 0, " hard"},
+};
+
+static int game_fetch_preset(int i, char **name, game_params **params)
+{
+ game_params *ret;
+ char str[80];
+
+ if (i < 0 || i >= lenof(netslide_presets))
+ return FALSE;
+
+ ret = snew(game_params);
+ ret->width = netslide_presets[i].x;
+ ret->height = netslide_presets[i].y;
+ ret->wrapping = netslide_presets[i].wrap;
+ ret->barrier_probability = (float)netslide_presets[i].bprob;
+ ret->movetarget = 0;
+
+ sprintf(str, "%dx%d%s", ret->width, ret->height, netslide_presets[i].desc);
+
+ *name = dupstr(str);
+ *params = ret;
+ return TRUE;
+}
+
+static void free_params(game_params *params)
+{
+ sfree(params);
+}
+
+static game_params *dup_params(const game_params *params)
+{
+ game_params *ret = snew(game_params);
+ *ret = *params; /* structure copy */
+ return ret;
+}
+
+static void decode_params(game_params *ret, char const *string)
+{
+ char const *p = string;
+
+ ret->wrapping = FALSE;
+ ret->barrier_probability = 0.0;
+ ret->movetarget = 0;
+
+ ret->width = atoi(p);
+ while (*p && isdigit((unsigned char)*p)) p++;
+ if (*p == 'x') {
+ p++;
+ ret->height = atoi(p);
+ while (*p && isdigit((unsigned char)*p)) p++;
+ if ( (ret->wrapping = (*p == 'w')) != 0 )
+ p++;
+ if (*p == 'b') {
+ ret->barrier_probability = (float)atof(++p);
+ while (*p && (isdigit((unsigned char)*p) || *p == '.')) p++;
+ }
+ if (*p == 'm') {
+ ret->movetarget = atoi(++p);
+ }
+ } else {
+ ret->height = ret->width;
+ }
+}
+
+static char *encode_params(const game_params *params, int full)
+{
+ char ret[400];
+ int len;
+
+ len = sprintf(ret, "%dx%d", params->width, params->height);
+ if (params->wrapping)
+ ret[len++] = 'w';
+ if (full && params->barrier_probability)
+ len += sprintf(ret+len, "b%g", params->barrier_probability);
+ /* Shuffle limit is part of the limited parameters, because we have to
+ * provide the target move count. */
+ if (params->movetarget)
+ len += sprintf(ret+len, "m%d", params->movetarget);
+ assert(len < lenof(ret));
+ ret[len] = '\0';
+
+ return dupstr(ret);
+}
+
+static config_item *game_configure(const game_params *params)
+{
+ config_item *ret;
+ char buf[80];
+
+ ret = snewn(6, 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 = "Number of shuffling moves";
+ ret[4].type = C_STRING;
+ sprintf(buf, "%d", params->movetarget);
+ ret[4].sval = dupstr(buf);
+ ret[4].ival = 0;
+
+ ret[5].name = NULL;
+ ret[5].type = C_END;
+ ret[5].sval = NULL;
+ ret[5].ival = 0;
+
+ return ret;
+}
+
+static game_params *custom_params(const 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);
+ ret->movetarget = atoi(cfg[4].sval);
+
+ return ret;
+}
+
+static char *validate_params(const game_params *params, int full)
+{
+ if (params->width <= 1 || params->height <= 1)
+ return "Width and height must both 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 description.
+ */
+
+static char *new_game_desc(const game_params *params, random_state *rs,
+ char **aux, int interactive)
+{
+ tree234 *possibilities, *barriertree;
+ int w, h, x, y, cx, cy, nbarriers;
+ unsigned char *tiles, *barriers;
+ char *desc, *p;
+
+ w = params->width;
+ h = params->height;
+
+ tiles = snewn(w * h, unsigned char);
+ memset(tiles, 0, w * h);
+ barriers = snewn(w * h, unsigned char);
+ memset(barriers, 0, w * h);
+
+ cx = w / 2;
+ cy = h / 2;
+
+ /*
+ * 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 (cx+1 < w)
+ add234(possibilities, new_xyd(cx, cy, R));
+ if (cy-1 >= 0)
+ add234(possibilities, new_xyd(cx, cy, U));
+ if (cx-1 >= 0)
+ add234(possibilities, new_xyd(cx, cy, L));
+ if (cy+1 < h)
+ add234(possibilities, new_xyd(cx, 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, params);
+ d2 = F(d1);
+#ifdef GENERATION_DIAGNOSTICS
+ 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.)
+ */
+ index(params, tiles, x1, y1) |= d1;
+ assert(index(params, tiles, x2, y2) == 0);
+ index(params, tiles, x2, y2) |= d2;
+
+ /*
+ * If we have created a T-piece, remove its last
+ * possibility.
+ */
+ if (COUNT(index(params, tiles, x1, y1)) == 3) {
+ struct xyd xyd1, *xydp;
+
+ xyd1.x = x1;
+ xyd1.y = y1;
+ xyd1.direction = 0x0F ^ index(params, tiles, x1, y1);
+
+ xydp = find234(possibilities, &xyd1, NULL);
+
+ if (xydp) {
+#ifdef GENERATION_DIAGNOSTICS
+ 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, params);
+ d3 = F(d);
+
+ xyd1.x = x3;
+ xyd1.y = y3;
+ xyd1.direction = d3;
+
+ xydp = find234(possibilities, &xyd1, NULL);
+
+ if (xydp) {
+#ifdef GENERATION_DIAGNOSTICS
+ 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 (!params->wrapping) {
+ if (d == U && y2 == 0)
+ continue;
+ if (d == D && y2 == h-1)
+ continue;
+ if (d == L && x2 == 0)
+ continue;
+ if (d == R && x2 == w-1)
+ continue;
+ }
+
+ OFFSET(x3, y3, x2, y2, d, params);
+
+ if (index(params, tiles, x3, y3))
+ continue; /* this would create a loop */
+
+#ifdef GENERATION_DIAGNOSTICS
+ 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.
+ */
+ barriertree = newtree234(xyd_cmp);
+ for (y = 0; y < h; y++) {
+ for (x = 0; x < w; x++) {
+
+ if (!(index(params, tiles, x, y) & R) &&
+ (params->wrapping || x < w-1))
+ add234(barriertree, new_xyd(x, y, R));
+ if (!(index(params, tiles, x, y) & D) &&
+ (params->wrapping || y < h-1))
+ add234(barriertree, new_xyd(x, y, D));
+ }
+ }
+
+ /*
+ * Save the unshuffled grid in aux.
+ */
+ {
+ char *solution;
+ int i;
+
+ /*
+ * String format is exactly the same as a solve move, so we
+ * can just dupstr this in solve_game().
+ */
+
+ solution = snewn(w * h + 2, char);
+ solution[0] = 'S';
+ for (i = 0; i < w * h; i++)
+ solution[i+1] = "0123456789abcdef"[tiles[i] & 0xF];
+ solution[w*h+1] = '\0';
+
+ *aux = solution;
+ }
+
+ /*
+ * Now shuffle the grid.
+ * FIXME - this simply does a set of random moves to shuffle the pieces,
+ * although we make a token effort to avoid boring cases by avoiding moves
+ * that directly undo the previous one, or that repeat so often as to
+ * turn into fewer moves.
+ *
+ * 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 = w - 1;
+ int rows = h - 1;
+ int moves = params->movetarget;
+ int prevdir = -1, prevrowcol = -1, nrepeats = 0;
+ if (!moves) moves = cols * rows * 2;
+ for (i = 0; i < moves; /* incremented conditionally */) {
+ /* Choose a direction: 0,1,2,3 = up, right, down, left. */
+ int dir = random_upto(rs, 4);
+ int rowcol;
+ if (dir % 2 == 0) {
+ int col = random_upto(rs, cols);
+ if (col >= cx) col += 1; /* avoid centre */
+ if (col == prevrowcol) {
+ if (dir == 2-prevdir)
+ continue; /* undoes last move */
+ else if (dir == prevdir && (nrepeats+1)*2 > h)
+ continue; /* makes fewer moves */
+ }
+ slide_col_int(w, h, tiles, 1 - dir, col);
+ rowcol = col;
+ } else {
+ int row = random_upto(rs, rows);
+ if (row >= cy) row += 1; /* avoid centre */
+ if (row == prevrowcol) {
+ if (dir == 4-prevdir)
+ continue; /* undoes last move */
+ else if (dir == prevdir && (nrepeats+1)*2 > w)
+ continue; /* makes fewer moves */
+ }
+ slide_row_int(w, h, tiles, 2 - dir, row);
+ rowcol = row;
+ }
+ if (dir == prevdir && rowcol == prevrowcol)
+ nrepeats++;
+ else
+ nrepeats = 1;
+ prevdir = dir;
+ prevrowcol = rowcol;
+ i++; /* if we got here, the move was accepted */
+ }
+ }
+
+ /*
+ * And now choose barrier locations. (We carefully do this
+ * _after_ shuffling, so that changing the barrier rate in the
+ * params while keeping the random 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(barriertree));
+ assert(nbarriers >= 0 && nbarriers <= count234(barriertree));
+
+ 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(barriertree));
+ xyd = delpos234(barriertree, i);
+
+ assert(xyd != NULL);
+
+ x1 = xyd->x;
+ y1 = xyd->y;
+ d1 = xyd->direction;
+ sfree(xyd);
+
+ OFFSET(x2, y2, x1, y1, d1, params);
+ d2 = F(d1);
+
+ index(params, barriers, x1, y1) |= d1;
+ index(params, barriers, x2, y2) |= d2;
+
+ nbarriers--;
+ }
+
+ /*
+ * Clean up the rest of the barrier list.
+ */
+ {
+ struct xyd *xyd;
+
+ while ( (xyd = delpos234(barriertree, 0)) != NULL)
+ sfree(xyd);
+
+ freetree234(barriertree);
+ }
+
+ /*
+ * Finally, encode the grid into a string game description.
+ *
+ * My syntax is extremely simple: each square is encoded as a
+ * hex digit in which bit 0 means a connection on the right,
+ * bit 1 means up, bit 2 left and bit 3 down. (i.e. the same
+ * encoding as used internally). Each digit is followed by
+ * optional barrier indicators: `v' means a vertical barrier to
+ * the right of it, and `h' means a horizontal barrier below
+ * it.
+ */
+ desc = snewn(w * h * 3 + 1, char);
+ p = desc;
+ for (y = 0; y < h; y++) {
+ for (x = 0; x < w; x++) {
+ *p++ = "0123456789abcdef"[index(params, tiles, x, y)];
+ if ((params->wrapping || x < w-1) &&
+ (index(params, barriers, x, y) & R))
+ *p++ = 'v';
+ if ((params->wrapping || y < h-1) &&
+ (index(params, barriers, x, y) & D))
+ *p++ = 'h';
+ }
+ }
+ assert(p - desc <= w*h*3);
+ *p = '\0';
+
+ sfree(tiles);
+ sfree(barriers);
+
+ return desc;
+}
+
+static char *validate_desc(const game_params *params, const char *desc)
+{
+ int w = params->width, h = params->height;
+ int i;
+
+ for (i = 0; i < w*h; i++) {
+ if (*desc >= '0' && *desc <= '9')
+ /* OK */;
+ else if (*desc >= 'a' && *desc <= 'f')
+ /* OK */;
+ else if (*desc >= 'A' && *desc <= 'F')
+ /* OK */;
+ else if (!*desc)
+ return "Game description shorter than expected";
+ else
+ return "Game description contained unexpected character";
+ desc++;
+ while (*desc == 'h' || *desc == 'v')
+ desc++;
+ }
+ if (*desc)
+ return "Game description longer than expected";
+
+ return NULL;
+}
+
+/* ----------------------------------------------------------------------
+ * Construct an initial game state, given a description and parameters.
+ */
+
+static game_state *new_game(midend *me, const game_params *params,
+ const char *desc)
+{
+ game_state *state;
+ int w, h, x, y;
+
+ 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->movetarget = params->movetarget;
+ state->completed = 0;
+ state->used_solve = FALSE;
+ 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);
+
+
+ /*
+ * Parse the game description into the grid.
+ */
+ for (y = 0; y < h; y++) {
+ for (x = 0; x < w; x++) {
+ if (*desc >= '0' && *desc <= '9')
+ tile(state, x, y) = *desc - '0';
+ else if (*desc >= 'a' && *desc <= 'f')
+ tile(state, x, y) = *desc - 'a' + 10;
+ else if (*desc >= 'A' && *desc <= 'F')
+ tile(state, x, y) = *desc - 'A' + 10;
+ if (*desc)
+ desc++;
+ while (*desc == 'h' || *desc == 'v') {
+ int x2, y2, d1, d2;
+ if (*desc == 'v')
+ d1 = R;
+ else
+ d1 = D;
+
+ OFFSET(x2, y2, x, y, d1, state);
+ d2 = F(d1);
+
+ barrier(state, x, y) |= d1;
+ barrier(state, x2, y2) |= d2;
+
+ desc++;
+ }
+ }
+ }
+
+ /*
+ * 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;
+ }
+ }
+
+ /*
+ * 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);
+ }
+ }
+ }
+ }
+
+ return state;
+}
+
+static game_state *dup_game(const 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->movetarget = state->movetarget;
+ ret->completed = state->completed;
+ ret->used_solve = state->used_solve;
+ 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);
+}
+
+static char *solve_game(const game_state *state, const game_state *currstate,
+ const char *aux, char **error)
+{
+ if (!aux) {
+ *error = "Solution not known for this puzzle";
+ return NULL;
+ }
+
+ return dupstr(aux);
+}
+
+static int game_can_format_as_text_now(const game_params *params)
+{
+ return TRUE;
+}
+
+static char *game_text_format(const game_state *state)
+{
+ return NULL;
+}
+
+/* ----------------------------------------------------------------------
+ * 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(const 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(const game_state *state)
+{
+ game_ui *ui = snew(game_ui);
+ ui->cur_x = 0;
+ ui->cur_y = -1;
+ ui->cur_visible = FALSE;
+
+ return ui;
+}
+
+static void free_ui(game_ui *ui)
+{
+ sfree(ui);
+}
+
+static char *encode_ui(const game_ui *ui)
+{
+ return NULL;
+}
+
+static void decode_ui(game_ui *ui, const char *encoding)
+{
+}
+
+/* ----------------------------------------------------------------------
+ * Process a move.
+ */
+
+static void slide_row_int(int w, int h, unsigned char *tiles, int dir, int row)
+{
+ int x = dir > 0 ? -1 : w;
+ int tx = x + dir;
+ int n = w - 1;
+ unsigned char endtile = tiles[row * w + tx];
+ do {
+ x = tx;
+ tx = (x + dir + w) % w;
+ tiles[row * w + x] = tiles[row * w + tx];
+ } while (--n > 0);
+ tiles[row * w + tx] = endtile;
+}
+
+static void slide_col_int(int w, int h, unsigned char *tiles, int dir, int col)
+{
+ int y = dir > 0 ? -1 : h;
+ int ty = y + dir;
+ int n = h - 1;
+ unsigned char endtile = tiles[ty * w + col];
+ do {
+ y = ty;
+ ty = (y + dir + h) % h;
+ tiles[y * w + col] = tiles[ty * w + col];
+ } while (--n > 0);
+ tiles[ty * w + col] = endtile;
+}
+
+static void slide_row(game_state *state, int dir, int row)
+{
+ slide_row_int(state->width, state->height, state->tiles, dir, row);
+}
+
+static void slide_col(game_state *state, int dir, int col)
+{
+ slide_col_int(state->width, state->height, state->tiles, dir, col);
+}
+
+static void game_changed_state(game_ui *ui, const game_state *oldstate,
+ const game_state *newstate)
+{
+}
+
+struct game_drawstate {
+ int started;
+ int width, height;
+ int tilesize;
+ unsigned char *visible;
+ int cur_x, cur_y;
+};
+
+static char *interpret_move(const game_state *state, game_ui *ui,
+ const game_drawstate *ds,
+ int x, int y, int button)
+{
+ int cx, cy;
+ int dx, dy;
+ char buf[80];
+
+ button &= ~MOD_MASK;
+
+ if (IS_CURSOR_MOVE(button)) {
+ int cpos, diff = 0;
+ cpos = c2pos(state->width, state->height, ui->cur_x, ui->cur_y);
+ diff = c2diff(state->width, state->height, ui->cur_x, ui->cur_y, button);
+
+ if (diff != 0) {
+ do { /* we might have to do this more than once to skip missing arrows */
+ cpos += diff;
+ pos2c(state->width, state->height, cpos, &ui->cur_x, &ui->cur_y);
+ } while (ui->cur_x == state->cx || ui->cur_y == state->cy);
+ }
+
+ ui->cur_visible = 1;
+ return "";
+ }
+
+ if (button == LEFT_BUTTON || button == RIGHT_BUTTON) {
+ 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;
+ ui->cur_visible = 0;
+ } else if (IS_CURSOR_SELECT(button)) {
+ if (ui->cur_visible) {
+ cx = ui->cur_x;
+ cy = ui->cur_y;
+ } else {
+ /* 'click' when cursor is invisible just makes cursor visible. */
+ ui->cur_visible = 1;
+ return "";
+ }
+ } else
+ return NULL;
+
+ if (cy >= 0 && cy < state->height && cy != state->cy)
+ {
+ if (cx == -1) dx = +1;
+ else if (cx == state->width) dx = -1;
+ else return NULL;
+ 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;
+ dx = 0;
+ }
+ else
+ return NULL;
+
+ /* reverse direction if right hand button is pressed */
+ if (button == RIGHT_BUTTON)
+ {
+ dx = -dx;
+ dy = -dy;
+ }
+
+ if (dx == 0)
+ sprintf(buf, "C%d,%d", cx, dy);
+ else
+ sprintf(buf, "R%d,%d", cy, dx);
+ return dupstr(buf);
+}
+
+static game_state *execute_move(const game_state *from, const char *move)
+{
+ game_state *ret;
+ int c, d, col;
+
+ if ((move[0] == 'C' || move[0] == 'R') &&
+ sscanf(move+1, "%d,%d", &c, &d) == 2 &&
+ c >= 0 && c < (move[0] == 'C' ? from->width : from->height)) {
+ col = (move[0] == 'C');
+ } else if (move[0] == 'S' &&
+ strlen(move) == from->width * from->height + 1) {
+ int i;
+ ret = dup_game(from);
+ ret->used_solve = TRUE;
+ ret->completed = ret->move_count = 1;
+
+ for (i = 0; i < from->width * from->height; i++) {
+ c = move[i+1];
+ if (c >= '0' && c <= '9')
+ c -= '0';
+ else if (c >= 'A' && c <= 'F')
+ c -= 'A' - 10;
+ else if (c >= 'a' && c <= 'f')
+ c -= 'a' - 10;
+ else {
+ free_game(ret);
+ return NULL;
+ }
+ ret->tiles[i] = c;
+ }
+ return ret;
+ } else
+ return NULL; /* can't parse move string */
+
+ ret = dup_game(from);
+
+ if (col)
+ slide_col(ret, d, c);
+ else
+ slide_row(ret, d, c);
+
+ ret->move_count++;
+ ret->last_move_row = col ? -1 : c;
+ ret->last_move_col = col ? c : -1;
+ ret->last_move_dir = d;
+
+ /*
+ * 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.
+ */
+
+static game_drawstate *game_new_drawstate(drawing *dr, const 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);
+ ds->tilesize = 0; /* not decided yet */
+ memset(ds->visible, 0xFF, state->width * state->height);
+ ds->cur_x = ds->cur_y = -1;
+
+ return ds;
+}
+
+static void game_free_drawstate(drawing *dr, game_drawstate *ds)
+{
+ sfree(ds->visible);
+ sfree(ds);
+}
+
+static void game_compute_size(const game_params *params, int tilesize,
+ int *x, int *y)
+{
+ /* Ick: fake up `ds->tilesize' for macro expansion purposes */
+ struct { int tilesize; } ads, *ds = &ads;
+ ads.tilesize = tilesize;
+
+ *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 void game_set_size(drawing *dr, game_drawstate *ds,
+ const game_params *params, int tilesize)
+{
+ ds->tilesize = tilesize;
+}
+
+static float *game_colours(frontend *fe, 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_filled_line(drawing *dr, int x1, int y1, int x2, int y2,
+ int colour)
+{
+ draw_line(dr, x1-1, y1, x2-1, y2, COL_WIRE);
+ draw_line(dr, x1+1, y1, x2+1, y2, COL_WIRE);
+ draw_line(dr, x1, y1-1, x2, y2-1, COL_WIRE);
+ draw_line(dr, x1, y1+1, x2, y2+1, COL_WIRE);
+ draw_line(dr, x1, y1, x2, y2, colour);
+}
+
+static void draw_rect_coords(drawing *dr, 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(dr, mx, my, dx, dy, colour);
+}
+
+static void draw_barrier_corner(drawing *dr, game_drawstate *ds,
+ 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(dr, bx+x1, by+y1,
+ bx+x1-TILE_BORDER*dx, by+y1-(TILE_BORDER-1)*dy,
+ COL_WIRE);
+ draw_rect_coords(dr, bx+x1, by+y1,
+ bx+x1-(TILE_BORDER-1)*dx, by+y1-TILE_BORDER*dy,
+ COL_WIRE);
+ } else {
+ draw_rect_coords(dr, bx+x1, by+y1,
+ bx+x1-(TILE_BORDER-1)*dx, by+y1-(TILE_BORDER-1)*dy,
+ COL_BARRIER);
+ }
+}
+
+static void draw_barrier(drawing *dr, game_drawstate *ds,
+ 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(dr, bx+x1-X(dir), by+y1-Y(dir), w, h, COL_WIRE);
+ } else {
+ draw_rect(dr, bx+x1, by+y1, w, h, COL_BARRIER);
+ }
+}
+
+static void draw_tile(drawing *dr, game_drawstate *ds, const game_state *state,
+ int x, int y, int tile, float xshift, float yshift)
+{
+ int bx = BORDER + WINDOW_OFFSET + TILE_SIZE * x + (int)(xshift * TILE_SIZE);
+ int by = BORDER + WINDOW_OFFSET + TILE_SIZE * y + (int)(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(dr, bx, by, TILE_SIZE+TILE_BORDER, TILE_SIZE+TILE_BORDER,
+ COL_BORDER);
+ draw_rect(dr, 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_filled_line(dr, 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(dr, 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(dr, points, 4, col, 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(dr, px-vx, py-vy, px+lx+vx, py+ly+vy, COL_WIRE);
+ draw_rect_coords(dr, 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(dr, px, py, px, py, COL_WIRE);
+ }
+ }
+
+ draw_update(dr, bx, by, TILE_SIZE+TILE_BORDER, TILE_SIZE+TILE_BORDER);
+}
+
+static void draw_tile_barriers(drawing *dr, game_drawstate *ds,
+ const 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(dr, ds, x, y, dir << 4, phase);
+ for (dir = 1; dir < 0x10; dir <<= 1)
+ if (barrier(state, x, y) & dir)
+ draw_barrier(dr, ds, x, y, dir, phase);
+ }
+
+ draw_update(dr, bx, by, TILE_SIZE+TILE_BORDER, TILE_SIZE+TILE_BORDER);
+}
+
+static void draw_arrow(drawing *dr, game_drawstate *ds,
+ int x, int y, int xdx, int xdy, int cur)
+{
+ 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(dr, coords, 7, cur ? COL_POWERED : COL_LOWLIGHT, COL_TEXT);
+}
+
+static void draw_arrow_for_cursor(drawing *dr, game_drawstate *ds,
+ int cur_x, int cur_y, int cur)
+{
+ if (cur_x == -1 && cur_y == -1)
+ return; /* 'no cursur here */
+ else if (cur_x == -1) /* LH column. */
+ draw_arrow(dr, ds, 0, cur_y+1, 0, -1, cur);
+ else if (cur_x == ds->width) /* RH column */
+ draw_arrow(dr, ds, ds->width, cur_y, 0, +1, cur);
+ else if (cur_y == -1) /* Top row */
+ draw_arrow(dr, ds, cur_x, 0, +1, 0, cur);
+ else if (cur_y == ds->height) /* Bottom row */
+ draw_arrow(dr, ds, cur_x+1, ds->height, -1, 0, cur);
+ else
+ assert(!"Invalid cursor position");
+
+ draw_update(dr,
+ cur_x * TILE_SIZE + BORDER + WINDOW_OFFSET,
+ cur_y * TILE_SIZE + BORDER + WINDOW_OFFSET,
+ TILE_SIZE, TILE_SIZE);
+}
+
+static void game_redraw(drawing *dr, game_drawstate *ds,
+ const game_state *oldstate, const game_state *state,
+ int dir, const game_ui *ui,
+ float t, float ft)
+{
+ int x, y, frame;
+ unsigned char *active;
+ float xshift = 0.0;
+ float yshift = 0.0;
+ int cur_x = -1, cur_y = -1;
+
+ /*
+ * 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(dr, 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(dr, 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(dr, ds, x, -1, LD, phase);
+ if (barrier(state, x, 0) & RU)
+ draw_barrier_corner(dr, ds, x, -1, DR, phase);
+ if (barrier(state, x, 0) & U)
+ draw_barrier(dr, ds, x, -1, D, phase);
+ if (barrier(state, x, ds->height-1) & DR)
+ draw_barrier_corner(dr, ds, x, ds->height, RU, phase);
+ if (barrier(state, x, ds->height-1) & LD)
+ draw_barrier_corner(dr, ds, x, ds->height, UL, phase);
+ if (barrier(state, x, ds->height-1) & D)
+ draw_barrier(dr, ds, x, ds->height, U, phase);
+ }
+
+ for (y = 0; y < ds->height; y++) {
+ if (barrier(state, 0, y) & UL)
+ draw_barrier_corner(dr, ds, -1, y, RU, phase);
+ if (barrier(state, 0, y) & LD)
+ draw_barrier_corner(dr, ds, -1, y, DR, phase);
+ if (barrier(state, 0, y) & L)
+ draw_barrier(dr, ds, -1, y, R, phase);
+ if (barrier(state, ds->width-1, y) & RU)
+ draw_barrier_corner(dr, ds, ds->width, y, UL, phase);
+ if (barrier(state, ds->width-1, y) & DR)
+ draw_barrier_corner(dr, ds, ds->width, y, LD, phase);
+ if (barrier(state, ds->width-1, y) & R)
+ draw_barrier(dr, ds, ds->width, y, L, phase);
+ }
+ }
+
+ /*
+ * Arrows for making moves.
+ */
+ for (x = 0; x < ds->width; x++) {
+ if (x == state->cx) continue;
+ draw_arrow(dr, ds, x, 0, +1, 0, 0);
+ draw_arrow(dr, ds, x+1, ds->height, -1, 0, 0);
+ }
+ for (y = 0; y < ds->height; y++) {
+ if (y == state->cy) continue;
+ draw_arrow(dr, ds, ds->width, y, 0, +1, 0);
+ draw_arrow(dr, ds, 0, y+1, 0, -1, 0);
+ }
+ }
+ if (ui->cur_visible) {
+ cur_x = ui->cur_x; cur_y = ui->cur_y;
+ }
+ if (cur_x != ds->cur_x || cur_y != ds->cur_y) {
+ /* Cursor has changed; redraw two (prev and curr) arrows. */
+ assert(cur_x != state->cx && cur_y != state->cy);
+
+ draw_arrow_for_cursor(dr, ds, cur_x, cur_y, 1);
+ draw_arrow_for_cursor(dr, ds, ds->cur_x, ds->cur_y, 0);
+ ds->cur_x = cur_x; ds->cur_y = cur_y;
+ }
+
+ /* Check if this is an undo. If so, we will need to run any animation
+ * backwards.
+ */
+ if (oldstate && oldstate->move_count > state->move_count) {
+ const game_state * tmpstate = state;
+ state = oldstate;
+ oldstate = tmpstate;
+ t = ANIM_TIME - t;
+ }
+
+ 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 ? 0.0F :
+ (1 - t / ANIM_TIME) * state->last_move_dir;
+ yshift = state->last_move_col == -1 ? 0.0F :
+ (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(dr,
+ 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 : (float)0.0);
+ float ys = (x == state->last_move_col ? yshift : (float)0.0);
+
+ draw_tile(dr, ds, state, x, y, c, xs, ys);
+ if (xs < 0 && x == 0)
+ draw_tile(dr, ds, state, state->width, y, c, xs, ys);
+ else if (xs > 0 && x == state->width - 1)
+ draw_tile(dr, ds, state, -1, y, c, xs, ys);
+ else if (ys < 0 && y == 0)
+ draw_tile(dr, ds, state, x, state->height, c, xs, ys);
+ else if (ys > 0 && y == state->height - 1)
+ draw_tile(dr, ds, 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(dr, ds, state, x, y);
+
+ unclip(dr);
+
+ /*
+ * 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++;
+
+ if (state->used_solve)
+ sprintf(statusbuf, "Moves since auto-solve: %d",
+ state->move_count - state->completed);
+ else
+ sprintf(statusbuf, "%sMoves: %d",
+ (state->completed ? "COMPLETED! " : ""),
+ (state->completed ? state->completed : state->move_count));
+
+ if (state->movetarget)
+ sprintf(statusbuf + strlen(statusbuf), " (target %d)",
+ state->movetarget);
+
+ sprintf(statusbuf + strlen(statusbuf), " Active: %d/%d", a, n);
+
+ status_bar(dr, statusbuf);
+ }
+
+ sfree(active);
+}
+
+static float game_anim_length(const game_state *oldstate,
+ const game_state *newstate, int dir, game_ui *ui)
+{
+ return ANIM_TIME;
+}
+
+static float game_flash_length(const game_state *oldstate,
+ const game_state *newstate, int dir, game_ui *ui)
+{
+ /*
+ * If the game has just been completed, we display a completion
+ * flash.
+ */
+ if (!oldstate->completed && newstate->completed &&
+ !oldstate->used_solve && !newstate->used_solve) {
+ 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_status(const game_state *state)
+{
+ return state->completed ? +1 : 0;
+}
+
+static int game_timing_state(const game_state *state, game_ui *ui)
+{
+ return FALSE;
+}
+
+static void game_print_size(const game_params *params, float *x, float *y)
+{
+}
+
+static void game_print(drawing *dr, const game_state *state, int tilesize)
+{
+}
+
+#ifdef COMBINED
+#define thegame netslide
+#endif
+
+const struct game thegame = {
+ "Netslide", "games.netslide", "netslide",
+ 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,
+ TRUE, solve_game,
+ FALSE, game_can_format_as_text_now, game_text_format,
+ new_ui,
+ free_ui,
+ encode_ui,
+ decode_ui,
+ game_changed_state,
+ interpret_move,
+ execute_move,
+ PREFERRED_TILE_SIZE, game_compute_size, game_set_size,
+ game_colours,
+ game_new_drawstate,
+ game_free_drawstate,
+ game_redraw,
+ game_anim_length,
+ game_flash_length,
+ game_status,
+ FALSE, FALSE, game_print_size, game_print,
+ TRUE, /* wants_statusbar */
+ FALSE, game_timing_state,
+ 0, /* flags */
+};
+
+/* vim: set shiftwidth=4 tabstop=8: */