ref: 622a5ff678773eefd3fe1a246d1c14dcd7c3ce40
parent: 067f06053cb6283da3f2fb76c813ec3f50de8b48
author: Simon Tatham <anakin@pobox.com>
date: Sat Aug 27 05:21:22 EDT 2005
New puzzle: `Inertia', originally written for Windows by Ben Olmstead and reimplemented with the help of his source code which he was kind enough to release into the public domain. [originally from svn r6222]
--- a/Recipe
+++ b/Recipe
@@ -28,7 +28,7 @@
ALL = list NET NETSLIDE cube fifteen sixteen rect pattern solo twiddle
+ MINES samegame FLIP guess PEGS dominosa UNTANGLE blackbox SLANT
- + lightup MAP LOOPY
+ + lightup MAP LOOPY inertia
GTK = gtk printing ps
@@ -53,6 +53,7 @@
lightup : [X] GTK COMMON lightup
map : [X] GTK COMMON MAP
loopy : [X] GTK COMMON LOOPY
+inertia : [X] GTK COMMON inertia
# Auxiliary command-line programs.
solosolver : [U] solo[STANDALONE_SOLVER] malloc
@@ -88,6 +89,7 @@
lightup : [G] WINDOWS COMMON lightup
map : [G] WINDOWS COMMON MAP
loopy : [G] WINDOWS COMMON LOOPY
+inertia : [G] WINDOWS COMMON inertia
# Mac OS X unified application containing all the puzzles.
Puzzles : [MX] osx osx.icns osx-info.plist COMMON ALL
@@ -180,7 +182,7 @@
for i in cube net netslide fifteen sixteen twiddle \
pattern rect solo mines samegame flip guess \
pegs dominosa untangle blackbox slant lightup \
- map loopy; do \
+ map loopy inertia; do \
$(INSTALL_PROGRAM) -m 755 $$i $(DESTDIR)$(gamesdir)/$$i; \
done
!end
--- /dev/null
+++ b/inertia.c
@@ -1,0 +1,1323 @@
+/*
+ * inertia.c: Game involving navigating round a grid picking up
+ * gems.
+ *
+ * Game rules and basic generator design by Ben Olmstead.
+ * This re-implementation was written by Simon Tatham.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+#include <ctype.h>
+#include <math.h>
+
+#include "puzzles.h"
+
+/* Used in the game_state */
+#define BLANK 'b'
+#define GEM 'g'
+#define MINE 'm'
+#define STOP 's'
+#define WALL 'w'
+
+/* Used in the game IDs */
+#define START 'S'
+
+/* Used in the game generation */
+#define POSSGEM 'G'
+
+/* Used only in the game_drawstate*/
+#define UNDRAWN '?'
+
+#define DIRECTIONS 8
+#define DX(dir) ( (dir) & 3 ? (((dir) & 7) > 4 ? -1 : +1) : 0 )
+#define DY(dir) ( DX((dir)+6) )
+
+/*
+ * Lvalue macro which expects x and y to be in range.
+ */
+#define LV_AT(w, h, grid, x, y) ( (grid)[(y)*(w)+(x)] )
+
+/*
+ * Rvalue macro which can cope with x and y being out of range.
+ */
+#define AT(w, h, grid, x, y) ( (x)<0 || (x)>=(w) || (y)<0 || (y)>=(h) ? \
+ WALL : LV_AT(w, h, grid, x, y) )
+
+enum {+ COL_BACKGROUND,
+ COL_OUTLINE,
+ COL_HIGHLIGHT,
+ COL_LOWLIGHT,
+ COL_PLAYER,
+ COL_DEAD_PLAYER,
+ COL_MINE,
+ COL_GEM,
+ COL_WALL,
+ NCOLOURS
+};
+
+struct game_params {+ int w, h;
+};
+
+struct game_state {+ game_params p;
+ int px, py;
+ int gems;
+ char *grid;
+ int distance_moved;
+ int dead;
+};
+
+static game_params *default_params(void)
+{+ game_params *ret = snew(game_params);
+
+ ret->w = 10;
+ ret->h = 8;
+
+ return ret;
+}
+
+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 const struct game_params inertia_presets[] = {+ { 10, 8 },+ { 15, 12 },+ { 20, 16 },+};
+
+static int game_fetch_preset(int i, char **name, game_params **params)
+{+ game_params p, *ret;
+ char *retname;
+ char namebuf[80];
+
+ if (i < 0 || i >= lenof(inertia_presets))
+ return FALSE;
+
+ p = inertia_presets[i];
+ ret = dup_params(&p);
+ sprintf(namebuf, "%dx%d", ret->w, ret->h);
+ retname = dupstr(namebuf);
+
+ *params = ret;
+ *name = retname;
+ return TRUE;
+}
+
+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)
+{+ /*
+ * Avoid completely degenerate cases which only have one
+ * row/column. We probably could generate completable puzzles
+ * of that shape, but they'd be forced to be extremely boring
+ * and at large sizes would take a while to happen upon at
+ * random as well.
+ */
+ if (params->w < 2 || params->h < 2)
+ return "Width and height must both be at least two";
+
+ /*
+ * The grid construction algorithm creates 1/5 as many gems as
+ * grid squares, and must create at least one gem to have an
+ * actual puzzle. However, an area-five grid is ruled out by
+ * the above constraint, so the practical minimum is six.
+ */
+ if (params->w * params->h < 6)
+ return "Grid area must be at least six squares";
+
+ return NULL;
+}
+
+/* ----------------------------------------------------------------------
+ * Solver used by grid generator.
+ */
+
+struct solver_scratch {+ unsigned char *reachable_from, *reachable_to;
+ int *positions;
+};
+
+static struct solver_scratch *new_scratch(int w, int h)
+{+ struct solver_scratch *sc = snew(struct solver_scratch);
+
+ sc->reachable_from = snewn(w * h * DIRECTIONS, unsigned char);
+ sc->reachable_to = snewn(w * h * DIRECTIONS, unsigned char);
+ sc->positions = snewn(w * h * DIRECTIONS, int);
+
+ return sc;
+}
+
+static void free_scratch(struct solver_scratch *sc)
+{+ sfree(sc);
+}
+
+static int can_go(int w, int h, char *grid,
+ int x1, int y1, int dir1, int x2, int y2, int dir2)
+{+ /*
+ * Returns TRUE if we can transition directly from (x1,y1)
+ * going in direction dir1, to (x2,y2) going in direction dir2.
+ */
+
+ /*
+ * If we're actually in the middle of an unoccupyable square,
+ * we cannot make any move.
+ */
+ if (AT(w, h, grid, x1, y1) == WALL ||
+ AT(w, h, grid, x1, y1) == MINE)
+ return FALSE;
+
+ /*
+ * If a move is capable of stopping at x1,y1,dir1, and x2,y2 is
+ * the same coordinate as x1,y1, then we can make the
+ * transition (by stopping and changing direction).
+ *
+ * For this to be the case, we have to either have a wall
+ * beyond x1,y1,dir1, or have a stop on x1,y1.
+ */
+ if (x2 == x1 && y2 == y1 &&
+ (AT(w, h, grid, x1, y1) == STOP ||
+ AT(w, h, grid, x1, y1) == START ||
+ AT(w, h, grid, x1+DX(dir1), y1+DY(dir1)) == WALL))
+ return TRUE;
+
+ /*
+ * If a move is capable of continuing here, then x1,y1,dir1 can
+ * move one space further on.
+ */
+ if (x2 == x1+DX(dir1) && y2 == y1+DY(dir1) && dir1 == dir2 &&
+ (AT(w, h, grid, x2, y2) == BLANK ||
+ AT(w, h, grid, x2, y2) == GEM ||
+ AT(w, h, grid, x2, y2) == STOP ||
+ AT(w, h, grid, x2, y2) == START))
+ return TRUE;
+
+ /*
+ * That's it.
+ */
+ return FALSE;
+}
+
+static int find_gem_candidates(int w, int h, char *grid,
+ struct solver_scratch *sc)
+{+ int wh = w*h;
+ int head, tail;
+ int sx, sy, gx, gy, gd, pass, possgems;
+
+ /*
+ * This function finds all the candidate gem squares, which are
+ * precisely those squares which can be picked up on a loop
+ * from the starting point back to the starting point. Doing
+ * this may involve passing through such a square in the middle
+ * of a move; so simple breadth-first search over the _squares_
+ * of the grid isn't quite adequate, because it might be that
+ * we can only reach a gem from the start by moving over it in
+ * one direction, but can only return to the start if we were
+ * moving over it in another direction.
+ *
+ * Instead, we BFS over a space which mentions each grid square
+ * eight times - once for each direction. We also BFS twice:
+ * once to find out what square+direction pairs we can reach
+ * _from_ the start point, and once to find out what pairs we
+ * can reach the start point from. Then a square is reachable
+ * if any of the eight directions for that square has both
+ * flags set.
+ */
+
+ memset(sc->reachable_from, 0, wh * DIRECTIONS);
+ memset(sc->reachable_to, 0, wh * DIRECTIONS);
+
+ /*
+ * Find the starting square.
+ */
+ for (sy = 0; sy < h; sy++) {+ for (sx = 0; sx < w; sx++)
+ if (AT(w, h, grid, sx, sy) == START)
+ break;
+ if (sx < w)
+ break;
+ }
+ assert(sy < h);
+
+ for (pass = 0; pass < 2; pass++) {+ unsigned char *reachable = (pass == 0 ? sc->reachable_from :
+ sc->reachable_to);
+ int sign = (pass == 0 ? +1 : -1);
+ int dir;
+
+#ifdef SOLVER_DIAGNOSTICS
+ printf("starting pass %d\n", pass);+#endif
+
+ /*
+ * `head' and `tail' are indices within sc->positions which
+ * track the list of board positions left to process.
+ */
+ head = tail = 0;
+ for (dir = 0; dir < DIRECTIONS; dir++) {+ int index = (sy*w+sx)*DIRECTIONS+dir;
+ sc->positions[tail++] = index;
+ reachable[index] = TRUE;
+#ifdef SOLVER_DIAGNOSTICS
+ printf("starting point %d,%d,%d\n", sx, sy, dir);+#endif
+ }
+
+ /*
+ * Now repeatedly pick an element off the list and process
+ * it.
+ */
+ while (head < tail) {+ int index = sc->positions[head++];
+ int dir = index % DIRECTIONS;
+ int x = (index / DIRECTIONS) % w;
+ int y = index / (w * DIRECTIONS);
+ int n, x2, y2, d2, i2;
+
+#ifdef SOLVER_DIAGNOSTICS
+ printf("processing point %d,%d,%d\n", x, y, dir);+#endif
+ /*
+ * The places we attempt to switch to here are:
+ * - each possible direction change (all the other
+ * directions in this square)
+ * - one step further in the direction we're going (or
+ * one step back, if we're in the reachable_to pass).
+ */
+ for (n = -1; n < DIRECTIONS; n++) {+ if (n < 0) {+ x2 = x + sign * DX(dir);
+ y2 = y + sign * DY(dir);
+ d2 = dir;
+ } else {+ x2 = x;
+ y2 = y;
+ d2 = n;
+ }
+ i2 = (y2*w+x2)*DIRECTIONS+d2;
+ if (!reachable[i2]) {+ int ok;
+#ifdef SOLVER_DIAGNOSTICS
+ printf(" trying point %d,%d,%d", x2, y2, d2);+#endif
+ if (pass == 0)
+ ok = can_go(w, h, grid, x, y, dir, x2, y2, d2);
+ else
+ ok = can_go(w, h, grid, x2, y2, d2, x, y, dir);
+#ifdef SOLVER_DIAGNOSTICS
+ printf(" - %sok\n", ok ? "" : "not ");+#endif
+ if (ok) {+ sc->positions[tail++] = i2;
+ reachable[i2] = TRUE;
+ }
+ }
+ }
+ }
+ }
+
+ /*
+ * And that should be it. Now all we have to do is find the
+ * squares for which there exists _some_ direction such that
+ * the square plus that direction form a tuple which is both
+ * reachable from the start and reachable to the start.
+ */
+ possgems = 0;
+ for (gy = 0; gy < h; gy++)
+ for (gx = 0; gx < w; gx++)
+ if (AT(w, h, grid, gx, gy) == BLANK) {+ for (gd = 0; gd < DIRECTIONS; gd++) {+ int index = (gy*w+gx)*DIRECTIONS+gd;
+ if (sc->reachable_from[index] && sc->reachable_to[index]) {+#ifdef SOLVER_DIAGNOSTICS
+ printf("space at %d,%d is reachable via"+ " direction %d\n", gx, gy, gd);
+#endif
+ LV_AT(w, h, grid, gx, gy) = POSSGEM;
+ possgems++;
+ break;
+ }
+ }
+ }
+
+ return possgems;
+}
+
+/* ----------------------------------------------------------------------
+ * Grid generation code.
+ */
+
+static char *gengrid(int w, int h, random_state *rs)
+{+ int wh = w*h;
+ char *grid = snewn(wh+1, char);
+ struct solver_scratch *sc = new_scratch(w, h);
+ int maxdist_threshold, tries;
+
+ maxdist_threshold = 2;
+ tries = 0;
+
+ while (1) {+ int i, j;
+ int possgems;
+ int *dist, *list, head, tail, maxdist;
+
+ /*
+ * We're going to fill the grid with the five basic piece
+ * types in about 1/5 proportion. For the moment, though,
+ * we leave out the gems, because we'll put those in
+ * _after_ we run the solver to tell us where the viable
+ * locations are.
+ */
+ i = 0;
+ for (j = 0; j < wh/5; j++)
+ grid[i++] = WALL;
+ for (j = 0; j < wh/5; j++)
+ grid[i++] = STOP;
+ for (j = 0; j < wh/5; j++)
+ grid[i++] = MINE;
+ assert(i < wh);
+ grid[i++] = START;
+ while (i < wh)
+ grid[i++] = BLANK;
+ shuffle(grid, wh, sizeof(*grid), rs);
+
+ /*
+ * Find the viable gem locations, and immediately give up
+ * and try again if there aren't enough of them.
+ */
+ possgems = find_gem_candidates(w, h, grid, sc);
+ if (possgems < wh/5)
+ continue;
+
+ /*
+ * We _could_ now select wh/5 of the POSSGEMs and set them
+ * to GEM, and have a viable level. However, there's a
+ * chance that a large chunk of the level will turn out to
+ * be unreachable, so first we test for that.
+ *
+ * We do this by finding the largest distance from any
+ * square to the nearest POSSGEM, by breadth-first search.
+ * If this is above a critical threshold, we abort and try
+ * again.
+ *
+ * (This search is purely geometric, without regard to
+ * walls and long ways round.)
+ */
+ dist = sc->positions;
+ list = sc->positions + wh;
+ for (i = 0; i < wh; i++)
+ dist[i] = -1;
+ head = tail = 0;
+ for (i = 0; i < wh; i++)
+ if (grid[i] == POSSGEM) {+ dist[i] = 0;
+ list[tail++] = i;
+ }
+ maxdist = 0;
+ while (head < tail) {+ int pos, x, y, d;
+
+ pos = list[head++];
+ if (maxdist < dist[pos])
+ maxdist = dist[pos];
+
+ x = pos % w;
+ y = pos / w;
+
+ for (d = 0; d < DIRECTIONS; d++) {+ int x2, y2, p2;
+
+ x2 = x + DX(d);
+ y2 = y + DY(d);
+
+ if (x2 >= 0 && x2 < w && y2 >= 0 && y2 < h) {+ p2 = y2*w+x2;
+ if (dist[p2] < 0) {+ dist[p2] = dist[pos] + 1;
+ list[tail++] = p2;
+ }
+ }
+ }
+ }
+ assert(head == wh && tail == wh);
+
+ /*
+ * Now abandon this grid and go round again if maxdist is
+ * above the required threshold.
+ *
+ * We can safely start the threshold as low as 2. As we
+ * accumulate failed generation attempts, we gradually
+ * raise it as we get more desperate.
+ */
+ if (maxdist > maxdist_threshold) {+ tries++;
+ if (tries == 50) {+ maxdist_threshold++;
+ tries = 0;
+ }
+ continue;
+ }
+
+ /*
+ * Now our reachable squares are plausibly evenly
+ * distributed over the grid. I'm not actually going to
+ * _enforce_ that I place the gems in such a way as not to
+ * increase that maxdist value; I'm now just going to trust
+ * to the RNG to pick a sensible subset of the POSSGEMs.
+ */
+ j = 0;
+ for (i = 0; i < wh; i++)
+ if (grid[i] == POSSGEM)
+ list[j++] = i;
+ shuffle(list, j, sizeof(*list), rs);
+ for (i = 0; i < j; i++)
+ grid[list[i]] = (i < wh/5 ? GEM : BLANK);
+ break;
+ }
+
+ free_scratch(sc);
+
+ grid[wh] = '\0';
+
+ return grid;
+}
+
+static char *new_game_desc(game_params *params, random_state *rs,
+ char **aux, int interactive)
+{+ return gengrid(params->w, params->h, rs);
+}
+
+static char *validate_desc(game_params *params, char *desc)
+{+ int w = params->w, h = params->h, wh = w*h;
+ int starts = 0, gems = 0, i;
+
+ for (i = 0; i < wh; i++) {+ if (!desc[i])
+ return "Not enough data to fill grid";
+ if (desc[i] != WALL && desc[i] != START && desc[i] != STOP &&
+ desc[i] != GEM && desc[i] != MINE && desc[i] != BLANK)
+ return "Unrecognised character in game description";
+ if (desc[i] == START)
+ starts++;
+ if (desc[i] == GEM)
+ gems++;
+ }
+ if (desc[i])
+ return "Too much data to fill grid";
+ if (starts < 1)
+ return "No starting square specified";
+ if (starts > 1)
+ return "More than one starting square specified";
+ if (gems < 1)
+ return "No gems specified";
+
+ return NULL;
+}
+
+static game_state *new_game(midend *me, game_params *params, char *desc)
+{+ int w = params->w, h = params->h, wh = w*h;
+ int i;
+ game_state *state = snew(game_state);
+
+ state->p = *params; /* structure copy */
+
+ state->grid = snewn(wh, char);
+ assert(strlen(desc) == wh);
+ memcpy(state->grid, desc, wh);
+
+ state->px = state->py = -1;
+ state->gems = 0;
+ for (i = 0; i < wh; i++) {+ if (state->grid[i] == START) {+ state->grid[i] = STOP;
+ state->px = i % w;
+ state->py = i / w;
+ } else if (state->grid[i] == GEM) {+ state->gems++;
+ }
+ }
+
+ assert(state->gems > 0);
+ assert(state->px >= 0 && state->py >= 0);
+
+ state->distance_moved = 0;
+ state->dead = FALSE;
+
+ return state;
+}
+
+static game_state *dup_game(game_state *state)
+{+ int w = state->p.w, h = state->p.h, wh = w*h;
+ game_state *ret = snew(game_state);
+
+ ret->p = state->p;
+ ret->px = state->px;
+ ret->py = state->py;
+ ret->gems = state->gems;
+ ret->grid = snewn(wh, char);
+ ret->distance_moved = state->distance_moved;
+ ret->dead = FALSE;
+ memcpy(ret->grid, state->grid, wh);
+
+ return ret;
+}
+
+static void free_game(game_state *state)
+{+ sfree(state->grid);
+ sfree(state);
+}
+
+static char *solve_game(game_state *state, game_state *currstate,
+ char *aux, char **error)
+{+ return NULL;
+}
+
+static char *game_text_format(game_state *state)
+{+ return NULL;
+}
+
+struct game_ui {+ float anim_length;
+ int flashtype;
+ int deaths;
+ int just_made_move;
+ int just_died;
+};
+
+static game_ui *new_ui(game_state *state)
+{+ game_ui *ui = snew(game_ui);
+ ui->anim_length = 0.0F;
+ ui->flashtype = 0;
+ ui->deaths = 0;
+ ui->just_made_move = FALSE;
+ ui->just_died = FALSE;
+ return ui;
+}
+
+static void free_ui(game_ui *ui)
+{+ sfree(ui);
+}
+
+static char *encode_ui(game_ui *ui)
+{+ char buf[80];
+ /*
+ * The deaths counter needs preserving across a serialisation.
+ */
+ sprintf(buf, "D%d", ui->deaths);
+ return dupstr(buf);
+}
+
+static void decode_ui(game_ui *ui, char *encoding)
+{+ int p = 0;
+ sscanf(encoding, "D%d%n", &ui->deaths, &p);
+}
+
+static void game_changed_state(game_ui *ui, game_state *oldstate,
+ game_state *newstate)
+{+ /*
+ * Increment the deaths counter. We only do this if
+ * ui->just_made_move is set (redoing a suicide move doesn't
+ * kill you _again_), and also we only do it if the game isn't
+ * completed (once you're finished, you can play).
+ */
+ if (!oldstate->dead && newstate->dead && ui->just_made_move &&
+ newstate->gems) {+ ui->deaths++;
+ ui->just_died = TRUE;
+ } else {+ ui->just_died = FALSE;
+ }
+ ui->just_made_move = FALSE;
+}
+
+struct game_drawstate {+ game_params p;
+ int tilesize;
+ int started;
+ unsigned short *grid;
+ blitter *player_background;
+ int player_bg_saved, pbgx, pbgy;
+};
+
+#define PREFERRED_TILESIZE 32
+#define TILESIZE (ds->tilesize)
+#define BORDER (TILESIZE)
+#define HIGHLIGHT_WIDTH (TILESIZE / 10)
+#define COORD(x) ( (x) * TILESIZE + BORDER )
+#define FROMCOORD(x) ( ((x) - BORDER + TILESIZE) / TILESIZE - 1 )
+
+static char *interpret_move(game_state *state, game_ui *ui, game_drawstate *ds,
+ int x, int y, int button)
+{+ int w = state->p.w, h = state->p.h /*, wh = w*h */;
+ int dir;
+ char buf[80];
+
+ dir = -1;
+
+ if (button == LEFT_BUTTON) {+ /*
+ * Mouse-clicking near the target point (or, more
+ * accurately, in the appropriate octant) is an alternative
+ * way to input moves.
+ */
+
+ if (FROMCOORD(x) != state->px || FROMCOORD(y) != state->py) {+ int dx, dy;
+ float angle;
+
+ dx = FROMCOORD(x) - state->px;
+ dy = FROMCOORD(y) - state->py;
+ /* I pass dx,dy rather than dy,dx so that the octants
+ * end up the right way round. */
+ angle = atan2(dx, -dy);
+
+ angle = (angle + (PI/8)) / (PI/4);
+ assert(angle > -16.0F);
+ dir = (int)(angle + 16.0F) & 7;
+ }
+ } else if (button == CURSOR_UP || button == (MOD_NUM_KEYPAD | '8'))
+ dir = 0;
+ else if (button == CURSOR_DOWN || button == (MOD_NUM_KEYPAD | '2'))
+ dir = 4;
+ else if (button == CURSOR_LEFT || button == (MOD_NUM_KEYPAD | '4'))
+ dir = 6;
+ else if (button == CURSOR_RIGHT || button == (MOD_NUM_KEYPAD | '6'))
+ dir = 2;
+ else if (button == (MOD_NUM_KEYPAD | '7'))
+ dir = 7;
+ else if (button == (MOD_NUM_KEYPAD | '1'))
+ dir = 5;
+ else if (button == (MOD_NUM_KEYPAD | '9'))
+ dir = 1;
+ else if (button == (MOD_NUM_KEYPAD | '3'))
+ dir = 3;
+
+ if (dir < 0)
+ return NULL;
+
+ /*
+ * Reject the move if we can't make it at all due to a wall
+ * being in the way.
+ */
+ if (AT(w, h, state->grid, state->px+DX(dir), state->py+DY(dir)) == WALL)
+ return NULL;
+
+ /*
+ * Reject the move if we're dead!
+ */
+ if (state->dead)
+ return NULL;
+
+ /*
+ * Otherwise, we can make the move. All we need to specify is
+ * the direction.
+ */
+ ui->just_made_move = TRUE;
+ sprintf(buf, "%d", dir);
+ return dupstr(buf);
+}
+
+static game_state *execute_move(game_state *state, char *move)
+{+ int w = state->p.w, h = state->p.h /*, wh = w*h */;
+ int dir = atoi(move);
+ game_state *ret;
+
+ if (dir < 0 || dir >= DIRECTIONS)
+ return NULL; /* huh? */
+
+ if (state->dead)
+ return NULL;
+
+ if (AT(w, h, state->grid, state->px+DX(dir), state->py+DY(dir)) == WALL)
+ return NULL; /* wall in the way! */
+
+ /*
+ * Now make the move.
+ */
+ ret = dup_game(state);
+ ret->distance_moved = 0;
+ while (1) {+ ret->px += DX(dir);
+ ret->py += DY(dir);
+ ret->distance_moved++;
+
+ if (AT(w, h, ret->grid, ret->px, ret->py) == GEM) {+ LV_AT(w, h, ret->grid, ret->px, ret->py) = BLANK;
+ ret->gems--;
+ }
+
+ if (AT(w, h, ret->grid, ret->px, ret->py) == MINE) {+ ret->dead = TRUE;
+ break;
+ }
+
+ if (AT(w, h, ret->grid, ret->px, ret->py) == STOP ||
+ AT(w, h, ret->grid, ret->px+DX(dir),
+ ret->py+DY(dir)) == WALL)
+ break;
+ }
+
+ return ret;
+}
+
+/* ----------------------------------------------------------------------
+ * Drawing routines.
+ */
+
+static void game_compute_size(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 = 2 * BORDER + 1 + params->w * TILESIZE;
+ *y = 2 * BORDER + 1 + params->h * TILESIZE;
+}
+
+static void game_set_size(drawing *dr, game_drawstate *ds,
+ game_params *params, int tilesize)
+{+ ds->tilesize = tilesize;
+
+ assert(!ds->player_bg_saved);
+
+ if (ds->player_background)
+ blitter_free(dr, ds->player_background);
+ ds->player_background = blitter_new(dr, TILESIZE, TILESIZE);
+}
+
+static float *game_colours(frontend *fe, game_state *state, int *ncolours)
+{+ float *ret = snewn(3 * NCOLOURS, float);
+ int i;
+
+ game_mkhighlight(fe, ret, COL_BACKGROUND, COL_HIGHLIGHT, COL_LOWLIGHT);
+
+ ret[COL_OUTLINE * 3 + 0] = 0.0F;
+ ret[COL_OUTLINE * 3 + 1] = 0.0F;
+ ret[COL_OUTLINE * 3 + 2] = 0.0F;
+
+ ret[COL_PLAYER * 3 + 0] = 0.0F;
+ ret[COL_PLAYER * 3 + 1] = 1.0F;
+ ret[COL_PLAYER * 3 + 2] = 0.0F;
+
+ ret[COL_DEAD_PLAYER * 3 + 0] = 1.0F;
+ ret[COL_DEAD_PLAYER * 3 + 1] = 0.0F;
+ ret[COL_DEAD_PLAYER * 3 + 2] = 0.0F;
+
+ ret[COL_MINE * 3 + 0] = 0.0F;
+ ret[COL_MINE * 3 + 1] = 0.0F;
+ ret[COL_MINE * 3 + 2] = 0.0F;
+
+ ret[COL_GEM * 3 + 0] = 0.6F;
+ ret[COL_GEM * 3 + 1] = 1.0F;
+ ret[COL_GEM * 3 + 2] = 1.0F;
+
+ for (i = 0; i < 3; i++) {+ ret[COL_WALL * 3 + i] = (3 * ret[COL_BACKGROUND * 3 + i] +
+ 1 * ret[COL_HIGHLIGHT * 3 + i]) / 4;
+ }
+
+ *ncolours = NCOLOURS;
+ return ret;
+}
+
+static game_drawstate *game_new_drawstate(drawing *dr, game_state *state)
+{+ int w = state->p.w, h = state->p.h, wh = w*h;
+ struct game_drawstate *ds = snew(struct game_drawstate);
+ int i;
+
+ ds->tilesize = 0;
+
+ /* We can't allocate the blitter rectangle for the player background
+ * until we know what size to make it. */
+ ds->player_background = NULL;
+ ds->player_bg_saved = FALSE;
+ ds->pbgx = ds->pbgy = -1;
+
+ ds->p = state->p; /* structure copy */
+ ds->started = FALSE;
+ ds->grid = snewn(wh, unsigned short);
+ for (i = 0; i < wh; i++)
+ ds->grid[i] = UNDRAWN;
+
+ return ds;
+}
+
+static void game_free_drawstate(drawing *dr, game_drawstate *ds)
+{+ sfree(ds->grid);
+ sfree(ds);
+}
+
+static void draw_player(drawing *dr, game_drawstate *ds, int x, int y,
+ int dead)
+{+ if (dead) {+ int coords[DIRECTIONS*4];
+ int d;
+
+ for (d = 0; d < DIRECTIONS; d++) {+ float x1, y1, x2, y2, x3, y3, len;
+
+ x1 = DX(d);
+ y1 = DY(d);
+ len = sqrt(x1*x1+y1*y1); x1 /= len; y1 /= len;
+
+ x3 = DX(d+1);
+ y3 = DY(d+1);
+ len = sqrt(x3*x3+y3*y3); x3 /= len; y3 /= len;
+
+ x2 = (x1+x3) / 4;
+ y2 = (y1+y3) / 4;
+
+ coords[d*4+0] = x + TILESIZE/2 + (int)((TILESIZE*3/7) * x1);
+ coords[d*4+1] = y + TILESIZE/2 + (int)((TILESIZE*3/7) * y1);
+ coords[d*4+2] = x + TILESIZE/2 + (int)((TILESIZE*3/7) * x2);
+ coords[d*4+3] = y + TILESIZE/2 + (int)((TILESIZE*3/7) * y2);
+ }
+ draw_polygon(dr, coords, DIRECTIONS*2, COL_DEAD_PLAYER, COL_OUTLINE);
+ } else {+ draw_circle(dr, x + TILESIZE/2, y + TILESIZE/2,
+ TILESIZE/3, COL_PLAYER, COL_OUTLINE);
+ }
+ draw_update(dr, x, y, TILESIZE, TILESIZE);
+}
+
+#define FLASH_DEAD 0x100
+#define FLASH_WIN 0x200
+#define FLASH_MASK 0x300
+
+static void draw_tile(drawing *dr, game_drawstate *ds, int x, int y, int v)
+{+ int tx = COORD(x), ty = COORD(y);
+ int bg = (v & FLASH_DEAD ? COL_DEAD_PLAYER :
+ v & FLASH_WIN ? COL_HIGHLIGHT : COL_BACKGROUND);
+
+ v &= ~FLASH_MASK;
+
+ clip(dr, tx+1, ty+1, TILESIZE-1, TILESIZE-1);
+ draw_rect(dr, tx+1, ty+1, TILESIZE-1, TILESIZE-1, bg);
+
+ if (v == WALL) {+ int coords[6];
+
+ coords[0] = tx + TILESIZE;
+ coords[1] = ty + TILESIZE;
+ coords[2] = tx + TILESIZE;
+ coords[3] = ty + 1;
+ coords[4] = tx + 1;
+ coords[5] = ty + TILESIZE;
+ draw_polygon(dr, coords, 3, COL_LOWLIGHT, COL_LOWLIGHT);
+
+ coords[0] = tx + 1;
+ coords[1] = ty + 1;
+ draw_polygon(dr, coords, 3, COL_HIGHLIGHT, COL_HIGHLIGHT);
+
+ draw_rect(dr, tx + 1 + HIGHLIGHT_WIDTH, ty + 1 + HIGHLIGHT_WIDTH,
+ TILESIZE - 2*HIGHLIGHT_WIDTH,
+ TILESIZE - 2*HIGHLIGHT_WIDTH, COL_WALL);
+ } else if (v == MINE) {+ int cx = tx + TILESIZE / 2;
+ int cy = ty + TILESIZE / 2;
+ int r = TILESIZE / 2 - 3;
+ int coords[4*5*2];
+ int xdx = 1, xdy = 0, ydx = 0, ydy = 1;
+ int tdx, tdy, i;
+
+ for (i = 0; i < 4*5*2; i += 5*2) {+ coords[i+2*0+0] = cx - r/6*xdx + r*4/5*ydx;
+ coords[i+2*0+1] = cy - r/6*xdy + r*4/5*ydy;
+ coords[i+2*1+0] = cx - r/6*xdx + r*ydx;
+ coords[i+2*1+1] = cy - r/6*xdy + r*ydy;
+ coords[i+2*2+0] = cx + r/6*xdx + r*ydx;
+ coords[i+2*2+1] = cy + r/6*xdy + r*ydy;
+ coords[i+2*3+0] = cx + r/6*xdx + r*4/5*ydx;
+ coords[i+2*3+1] = cy + r/6*xdy + r*4/5*ydy;
+ coords[i+2*4+0] = cx + r*3/5*xdx + r*3/5*ydx;
+ coords[i+2*4+1] = cy + r*3/5*xdy + r*3/5*ydy;
+
+ tdx = ydx;
+ tdy = ydy;
+ ydx = xdx;
+ ydy = xdy;
+ xdx = -tdx;
+ xdy = -tdy;
+ }
+
+ draw_polygon(dr, coords, 5*4, COL_MINE, COL_MINE);
+
+ draw_rect(dr, cx-r/3, cy-r/3, r/3, r/4, COL_HIGHLIGHT);
+ } else if (v == STOP) {+ draw_circle(dr, tx + TILESIZE/2, ty + TILESIZE/2,
+ TILESIZE*3/7, -1, COL_OUTLINE);
+ draw_rect(dr, tx + TILESIZE*3/7, ty+1,
+ TILESIZE - 2*(TILESIZE*3/7) + 1, TILESIZE-1, bg);
+ draw_rect(dr, tx+1, ty + TILESIZE*3/7,
+ TILESIZE-1, TILESIZE - 2*(TILESIZE*3/7) + 1, bg);
+ } else if (v == GEM) {+ int coords[8];
+
+ coords[0] = tx+TILESIZE/2;
+ coords[1] = ty+TILESIZE*1/7;
+ coords[2] = tx+TILESIZE*1/7;
+ coords[3] = ty+TILESIZE/2;
+ coords[4] = tx+TILESIZE/2;
+ coords[5] = ty+TILESIZE-TILESIZE*1/7;
+ coords[6] = tx+TILESIZE-TILESIZE*1/7;
+ coords[7] = ty+TILESIZE/2;
+
+ draw_polygon(dr, coords, 4, COL_GEM, COL_OUTLINE);
+ }
+
+ unclip(dr);
+ draw_update(dr, tx, ty, TILESIZE, TILESIZE);
+}
+
+#define BASE_ANIM_LENGTH 0.1F
+#define FLASH_LENGTH 0.3F
+
+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->p.w, h = state->p.h /*, wh = w*h */;
+ int x, y;
+ float ap;
+ int player_dist;
+ int flashtype;
+ int gems, deaths;
+ char status[256];
+
+ if (flashtime &&
+ !((int)(flashtime * 3 / FLASH_LENGTH) % 2))
+ flashtype = ui->flashtype;
+ else
+ flashtype = 0;
+
+ /*
+ * Erase the player sprite.
+ */
+ if (ds->player_bg_saved) {+ assert(ds->player_background);
+ blitter_load(dr, ds->player_background, ds->pbgx, ds->pbgy);
+ draw_update(dr, ds->pbgx, ds->pbgy, TILESIZE, TILESIZE);
+ ds->player_bg_saved = FALSE;
+ }
+
+ /*
+ * Initialise a fresh drawstate.
+ */
+ if (!ds->started) {+ int wid, ht;
+
+ /*
+ * Blank out the window initially.
+ */
+ game_compute_size(&ds->p, TILESIZE, &wid, &ht);
+ draw_rect(dr, 0, 0, wid, ht, COL_BACKGROUND);
+ draw_update(dr, 0, 0, wid, ht);
+
+ /*
+ * Draw the grid lines.
+ */
+ for (y = 0; y <= h; y++)
+ draw_line(dr, COORD(0), COORD(y), COORD(w), COORD(y),
+ COL_LOWLIGHT);
+ for (x = 0; x <= w; x++)
+ draw_line(dr, COORD(x), COORD(0), COORD(x), COORD(h),
+ COL_LOWLIGHT);
+
+ ds->started = TRUE;
+ }
+
+ /*
+ * If we're in the process of animating a move, let's start by
+ * working out how far the player has moved from their _older_
+ * state.
+ */
+ if (oldstate) {+ ap = animtime / ui->anim_length;
+ player_dist = ap * (dir > 0 ? state : oldstate)->distance_moved;
+ } else {+ player_dist = 0;
+ ap = 0.0F;
+ }
+
+ /*
+ * Draw the grid contents.
+ *
+ * We count the gems as we go round this loop, for the purposes
+ * of the status bar. Of course we have a gems counter in the
+ * game_state already, but if we do the counting in this loop
+ * then it tracks gems being picked up in a sliding move, and
+ * updates one by one.
+ */
+ gems = 0;
+ for (y = 0; y < h; y++)
+ for (x = 0; x < w; x++) {+ unsigned short v = (unsigned char)state->grid[y*w+x];
+
+ /*
+ * Special case: if the player is in the process of
+ * moving over a gem, we draw the gem iff they haven't
+ * gone past it yet.
+ */
+ if (oldstate && oldstate->grid[y*w+x] != state->grid[y*w+x]) {+ /*
+ * Compute the distance from this square to the
+ * original player position.
+ */
+ int dist = max(abs(x - oldstate->px), abs(y - oldstate->py));
+
+ /*
+ * If the player has reached here, use the new grid
+ * element. Otherwise use the old one.
+ */
+ if (player_dist < dist)
+ v = oldstate->grid[y*w+x];
+ else
+ v = state->grid[y*w+x];
+ }
+
+ /*
+ * Special case: erase the mine the dead player is
+ * sitting on. Only at the end of the move.
+ */
+ if (v == MINE && !oldstate && state->dead &&
+ x == state->px && y == state->py)
+ v = BLANK;
+
+ if (v == GEM)
+ gems++;
+
+ v |= flashtype;
+
+ if (ds->grid[y*w+x] != v) {+ draw_tile(dr, ds, x, y, v);
+ ds->grid[y*w+x] = v;
+ }
+ }
+
+ /*
+ * Gem counter in the status bar. We replace it with
+ * `COMPLETED!' when it reaches zero ... or rather, when the
+ * _current state_'s gem counter is zero. (Thus, `Gems: 0' is
+ * shown between the collection of the last gem and the
+ * completion of the move animation that did it.)
+ */
+ if (state->dead && (!oldstate || oldstate->dead))
+ sprintf(status, "DEAD!");
+ else if (state->gems || (oldstate && oldstate->gems))
+ sprintf(status, "Gems: %d", gems);
+ else
+ sprintf(status, "COMPLETED!");
+ /* We subtract one from the visible death counter if we're still
+ * animating the move at the end of which the death took place. */
+ deaths = ui->deaths;
+ if (oldstate && ui->just_died) {+ assert(deaths > 0);
+ deaths--;
+ }
+ if (deaths)
+ sprintf(status + strlen(status), " Deaths: %d", deaths);
+ status_bar(dr, status);
+
+ /*
+ * Draw the player sprite.
+ */
+ assert(!ds->player_bg_saved);
+ assert(ds->player_background);
+ {+ int ox, oy, nx, ny;
+ nx = COORD(state->px);
+ ny = COORD(state->py);
+ if (oldstate) {+ ox = COORD(oldstate->px);
+ oy = COORD(oldstate->py);
+ } else {+ ox = nx;
+ oy = ny;
+ }
+ ds->pbgx = ox + ap * (nx - ox);
+ ds->pbgy = oy + ap * (ny - oy);
+ }
+ blitter_save(dr, ds->player_background, ds->pbgx, ds->pbgy);
+ draw_player(dr, ds, ds->pbgx, ds->pbgy, (state->dead && !oldstate));
+ ds->player_bg_saved = TRUE;
+}
+
+static float game_anim_length(game_state *oldstate, game_state *newstate,
+ int dir, game_ui *ui)
+{+ int dist;
+ if (dir > 0)
+ dist = newstate->distance_moved;
+ else
+ dist = oldstate->distance_moved;
+ ui->anim_length = sqrt(dist) * BASE_ANIM_LENGTH;
+ return ui->anim_length;
+}
+
+static float game_flash_length(game_state *oldstate, game_state *newstate,
+ int dir, game_ui *ui)
+{+ if (!oldstate->dead && newstate->dead) {+ ui->flashtype = FLASH_DEAD;
+ return FLASH_LENGTH;
+ } else if (oldstate->gems && !newstate->gems) {+ ui->flashtype = FLASH_WIN;
+ return FLASH_LENGTH;
+ }
+ return 0.0F;
+}
+
+static int game_wants_statusbar(void)
+{+ return TRUE;
+}
+
+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 inertia
+#endif
+
+const struct game thegame = {+ "Inertia", "games.inertia",
+ 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,
+ FALSE, 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,
+ game_wants_statusbar,
+ FALSE, game_timing_state,
+ 0, /* mouse_priorities */
+};
--- a/list.c
+++ b/list.c
@@ -23,6 +23,7 @@
extern const game fifteen;
extern const game flip;
extern const game guess;
+extern const game inertia;
extern const game lightup;
extern const game loopy;
extern const game map;
@@ -46,6 +47,7 @@
&fifteen,
&flip,
&guess,
+ &inertia,
&lightup,
&loopy,
&map,
--- a/puzzles.but
+++ b/puzzles.but
@@ -1715,6 +1715,58 @@
}
+\C{inertia} \i{Inertia}+
+\cfg{winhelp-topic}{games.inertia}+
+You are a small green ball sitting in a grid full of obstacles. Your
+aim is to collect all the gems without running into any mines.
+
+You can move the ball in any orthogonal \e{or diagonal} direction.+Once the ball starts moving, it will continue until something stops
+it. A wall directly in its path will stop it (but if it is moving
+diagonally, it will move through a diagonal gap between two other
+walls without stopping). Also, some of the squares are \q{stops};+when the ball moves on to a stop, it will stop moving no matter what
+direction it was going in. Gems do \e{not} stop the ball; it picks+them up and keeps on going.
+
+Running into a mine is fatal. Even if you picked up the last gem in
+the same move which then hit a mine, the game will count you as dead
+rather than victorious.
+
+This game was originally implemented for Windows by Ben Olmstead
+\k{bem}, who was kind enough to release his source code on request+so that it could be re-implemented for this collection.
+
+\B{bem} \W{http://xn13.com/}\cw{http://xn13.com/}+
+\H{inertia-controls} \i{Inertia controls}+
+\IM{Inertia controls} controls, for Inertia+\IM{Inertia controls} keys, for Inertia+\IM{Inertia controls} shortcuts (keyboard), for Inertia+
+You can move the ball in any of the eight directions using the
+numeric keypad. Alternatively, if you click the left mouse button on
+the grid, the ball will begin a move in the general direction of
+where you clicked.
+
+All the actions described in \k{common-actions} are also available.+In particular, if you do run into a mine and die, you can use the
+Undo function and resume playing from before the fatal move. The
+game will keep track of the number of times you have done this.
+
+\H{inertia-parameters} \I{parameters, for Inertia}Inertia parameters+
+These parameters are available from the \q{Custom...} option on the+\q{Type} menu.+
+\dt \e{Width}, \e{Height}+
+\dd Size of grid in squares.
+
+
\A{licence} \I{MIT licence}\ii{Licence} This software is \i{copyright} 2004-2005 Simon Tatham.--
⑨