puzzles.h

   1 /*
   2  * puzzles.h: header file for my puzzle collection
   3  */
   4
   5 #ifndef PUZZLES_PUZZLES_H
   6 #define PUZZLES_PUZZLES_H
   7
   8 #include <stdio.h>  /* for FILE */
   9 #include <stdlib.h> /* for size_t */
  10 #include <limits.h> /* for UINT_MAX */
  11
  12 #ifndef TRUE
  13 #define TRUE 1
  14 #endif
  15 #ifndef FALSE
  16 #define FALSE 0
  17 #endif
  18
  19 #define PI 3.141592653589793238462643383279502884197169399
  20
  21 #define lenof(array) ( sizeof(array) / sizeof(*(array)) )
  22
  23 #define STR_INT(x) #x
  24 #define STR(x) STR_INT(x)
  25
  26 /* NB not perfect because they evaluate arguments multiple times. */
  27 #ifndef max
  28 #define max(x,y) ( (x)>(y) ? (x) : (y) )
  29 #endif /* max */
  30 #ifndef min
  31 #define min(x,y) ( (x)<(y) ? (x) : (y) )
  32 #endif /* min */
  33
  34 enum {
  35     LEFT_BUTTON = 0x0200,
  36     MIDDLE_BUTTON,
  37     RIGHT_BUTTON,
  38     LEFT_DRAG,
  39     MIDDLE_DRAG,
  40     RIGHT_DRAG,
  41     LEFT_RELEASE,
  42     MIDDLE_RELEASE,
  43     RIGHT_RELEASE,
  44     CURSOR_UP,
  45     CURSOR_DOWN,
  46     CURSOR_LEFT,
  47     CURSOR_RIGHT,
  48     CURSOR_SELECT,
  49     CURSOR_SELECT2,
  50
  51     /* made smaller because of 'limited range of datatype' errors. */
  52     MOD_CTRL       = 0x1000,
  53     MOD_SHFT       = 0x2000,
  54     MOD_NUM_KEYPAD = 0x4000,
  55     MOD_MASK       = 0x7000 /* mask for all modifiers */
  56 };
  57
  58 #define IS_MOUSE_DOWN(m) ( (unsigned)((m) - LEFT_BUTTON) <= \
  59                                (unsigned)(RIGHT_BUTTON - LEFT_BUTTON))
  60 #define IS_MOUSE_DRAG(m) ( (unsigned)((m) - LEFT_DRAG) <= \
  61                                (unsigned)(RIGHT_DRAG - LEFT_DRAG))
  62 #define IS_MOUSE_RELEASE(m) ( (unsigned)((m) - LEFT_RELEASE) <= \
  63                                (unsigned)(RIGHT_RELEASE - LEFT_RELEASE))
  64 #define IS_CURSOR_MOVE(m) ( (m) == CURSOR_UP || (m) == CURSOR_DOWN || \
  65                             (m) == CURSOR_RIGHT || (m) == CURSOR_LEFT )
  66 #define IS_CURSOR_SELECT(m) ( (m) == CURSOR_SELECT || (m) == CURSOR_SELECT2)
  67
  68 /*
  69  * Flags in the back end's `flags' word.
  70  */
  71 /* Bit flags indicating mouse button priorities */
  72 #define BUTTON_BEATS(x,y) ( 1 << (((x)-LEFT_BUTTON)*3+(y)-LEFT_BUTTON) )
  73 /* Flag indicating that Solve operations should be animated */
  74 #define SOLVE_ANIMATES ( 1 << 9 )
  75 /* Pocket PC: Game requires right mouse button emulation */
  76 #define REQUIRE_RBUTTON ( 1 << 10 )
  77 /* Pocket PC: Game requires numeric input */
  78 #define REQUIRE_NUMPAD ( 1 << 11 )
  79 /* end of `flags' word definitions */
  80
  81 #ifdef _WIN32_WCE
  82   /* Pocket PC devices have small, portrait screen that requires more vivid colours */
  83   #define SMALL_SCREEN
  84   #define PORTRAIT_SCREEN
  85   #define VIVID_COLOURS
  86   #define STYLUS_BASED
  87 #endif
  88
  89 #define IGNOREARG(x) ( (x) = (x) )
  90
  91 typedef struct frontend frontend;
  92 typedef struct config_item config_item;
  93 typedef struct midend midend;
  94 typedef struct random_state random_state;
  95 typedef struct game_params game_params;
  96 typedef struct game_state game_state;
  97 typedef struct game_ui game_ui;
  98 typedef struct game_drawstate game_drawstate;
  99 typedef struct game game;
 100 typedef struct blitter blitter;
 101 typedef struct document document;
 102 typedef struct drawing_api drawing_api;
 103 typedef struct drawing drawing;
 104 typedef struct psdata psdata;
 105
 106 #define ALIGN_VNORMAL 0x000
 107 #define ALIGN_VCENTRE 0x100
 108
 109 #define ALIGN_HLEFT   0x000
 110 #define ALIGN_HCENTRE 0x001
 111 #define ALIGN_HRIGHT  0x002
 112
 113 #define FONT_FIXED    0
 114 #define FONT_VARIABLE 1
 115
 116 /* For printing colours */
 117 #define HATCH_SLASH     1
 118 #define HATCH_BACKSLASH 2
 119 #define HATCH_HORIZ     3
 120 #define HATCH_VERT      4
 121 #define HATCH_PLUS      5
 122 #define HATCH_X         6
 123
 124 /*
 125  * Structure used to pass configuration data between frontend and
 126  * game
 127  */
 128 enum { C_STRING, C_CHOICES, C_BOOLEAN, C_END };
 129 struct config_item {
 130     /*
 131      * `name' is never dynamically allocated.
 132      */
 133     char *name;
 134     /*
 135      * `type' contains one of the above values.
 136      */
 137     int type;
 138     /*
 139      * For C_STRING, `sval' is always dynamically allocated and
 140      * non-NULL. For C_BOOLEAN and C_END, `sval' is always NULL.
 141      * For C_CHOICES, `sval' is non-NULL, _not_ dynamically
 142      * allocated, and contains a set of option strings separated by
 143      * a delimiter. The delimeter is also the first character in
 144      * the string, so for example ":Foo:Bar:Baz" gives three
 145      * options `Foo', `Bar' and `Baz'.
 146      */
 147     char *sval;
 148     /*
 149      * For C_BOOLEAN, this is TRUE or FALSE. For C_CHOICES, it
 150      * indicates the chosen index from the `sval' list. In the
 151      * above example, 0==Foo, 1==Bar and 2==Baz.
 152      */
 153     int ival;
 154 };
 155
 156 /*
 157  * Platform routines
 158  */
 159
 160 /* We can't use #ifdef DEBUG, because Cygwin defines it by default. */
 161 #ifdef DEBUGGING
 162 #define debug(x) (debug_printf x)
 163 void debug_printf(char *fmt, ...);
 164 #else
 165 #define debug(x)
 166 #endif
 167
 168 void fatal(char *fmt, ...);
 169 void frontend_default_colour(frontend *fe, float *output);
 170 void deactivate_timer(frontend *fe);
 171 void activate_timer(frontend *fe);
 172 void get_random_seed(void **randseed, int *randseedsize);
 173
 174 /*
 175  * drawing.c
 176  */
 177 drawing *drawing_new(const drawing_api *api, midend *me, void *handle);
 178 void drawing_free(drawing *dr);
 179 void draw_text(drawing *dr, int x, int y, int fonttype, int fontsize,
 180                int align, int colour, char *text);
 181 void draw_rect(drawing *dr, int x, int y, int w, int h, int colour);
 182 void draw_line(drawing *dr, int x1, int y1, int x2, int y2, int colour);
 183 void draw_polygon(drawing *dr, int *coords, int npoints,
 184                   int fillcolour, int outlinecolour);
 185 void draw_circle(drawing *dr, int cx, int cy, int radius,
 186                  int fillcolour, int outlinecolour);
 187 void draw_thick_line(drawing *dr, float thickness,
 188                      float x1, float y1, float x2, float y2, int colour);
 189 void clip(drawing *dr, int x, int y, int w, int h);
 190 void unclip(drawing *dr);
 191 void start_draw(drawing *dr);
 192 void draw_update(drawing *dr, int x, int y, int w, int h);
 193 void end_draw(drawing *dr);
 194 char *text_fallback(drawing *dr, const char *const *strings, int nstrings);
 195 void status_bar(drawing *dr, char *text);
 196 blitter *blitter_new(drawing *dr, int w, int h);
 197 void blitter_free(drawing *dr, blitter *bl);
 198 /* save puts the portion of the current display with top-left corner
 199  * (x,y) to the blitter. load puts it back again to the specified
 200  * coords, or else wherever it was saved from
 201  * (if x = y = BLITTER_FROMSAVED). */
 202 void blitter_save(drawing *dr, blitter *bl, int x, int y);
 203 #define BLITTER_FROMSAVED (-1)
 204 void blitter_load(drawing *dr, blitter *bl, int x, int y);
 205 void print_begin_doc(drawing *dr, int pages);
 206 void print_begin_page(drawing *dr, int number);
 207 void print_begin_puzzle(drawing *dr, float xm, float xc,
 208                         float ym, float yc, int pw, int ph, float wmm,
 209                         float scale);
 210 void print_end_puzzle(drawing *dr);
 211 void print_end_page(drawing *dr, int number);
 212 void print_end_doc(drawing *dr);
 213 void print_get_colour(drawing *dr, int colour, int printing_in_colour,
 214                       int *hatch, float *r, float *g, float *b);
 215 int print_mono_colour(drawing *dr, int grey); /* 0==black, 1==white */
 216 int print_grey_colour(drawing *dr, float grey);
 217 int print_hatched_colour(drawing *dr, int hatch);
 218 int print_rgb_mono_colour(drawing *dr, float r, float g, float b, int mono);
 219 int print_rgb_grey_colour(drawing *dr, float r, float g, float b, float grey);
 220 int print_rgb_hatched_colour(drawing *dr, float r, float g, float b,
 221                              int hatch);
 222 void print_line_width(drawing *dr, int width);
 223 void print_line_dotted(drawing *dr, int dotted);
 224
 225 /*
 226  * midend.c
 227  */
 228 midend *midend_new(frontend *fe, const game *ourgame,
 229                    const drawing_api *drapi, void *drhandle);
 230 void midend_free(midend *me);
 231 void midend_set_params(midend *me, game_params *params);
 232 game_params *midend_get_params(midend *me);
 233 void midend_size(midend *me, int *x, int *y, int user_size);
 234 void midend_new_game(midend *me);
 235 void midend_restart_game(midend *me);
 236 void midend_stop_anim(midend *me);
 237 int midend_process_key(midend *me, int x, int y, int button);
 238 void midend_force_redraw(midend *me);
 239 void midend_redraw(midend *me);
 240 float *midend_colours(midend *me, int *ncolours);
 241 void midend_freeze_timer(midend *me, float tprop);
 242 void midend_timer(midend *me, float tplus);
 243 int midend_num_presets(midend *me);
 244 void midend_fetch_preset(midend *me, int n,
 245                          char **name, game_params **params);
 246 int midend_which_preset(midend *me);
 247 int midend_wants_statusbar(midend *me);
 248 enum { CFG_SETTINGS, CFG_SEED, CFG_DESC, CFG_FRONTEND_SPECIFIC };
 249 config_item *midend_get_config(midend *me, int which, char **wintitle);
 250 char *midend_set_config(midend *me, int which, config_item *cfg);
 251 char *midend_game_id(midend *me, char *id);
 252 char *midend_get_game_id(midend *me);
 253 int midend_can_format_as_text_now(midend *me);
 254 char *midend_text_format(midend *me);
 255 char *midend_solve(midend *me);
 256 int midend_status(midend *me);
 257 int midend_can_undo(midend *me);
 258 int midend_can_redo(midend *me);
 259 void midend_supersede_game_desc(midend *me, char *desc, char *privdesc);
 260 char *midend_rewrite_statusbar(midend *me, char *text);
 261 void midend_serialise(midend *me,
 262                       void (*write)(void *ctx, void *buf, int len),
 263                       void *wctx);
 264 char *midend_deserialise(midend *me,
 265                          int (*read)(void *ctx, void *buf, int len),
 266                          void *rctx);
 267 /* Printing functions supplied by the mid-end */
 268 char *midend_print_puzzle(midend *me, document *doc, int with_soln);
 269 int midend_tilesize(midend *me);
 270
 271 /*
 272  * malloc.c
 273  */
 274 void *smalloc(size_t size);
 275 void *srealloc(void *p, size_t size);
 276 void sfree(void *p);
 277 char *dupstr(const char *s);
 278 #define snew(type) \
 279     ( (type *) smalloc (sizeof (type)) )
 280 #define snewn(number, type) \
 281     ( (type *) smalloc ((number) * sizeof (type)) )
 282 #define sresize(array, number, type) \
 283     ( (type *) srealloc ((array), (number) * sizeof (type)) )
 284
 285 /*
 286  * misc.c
 287  */
 288 void free_cfg(config_item *cfg);
 289 void obfuscate_bitmap(unsigned char *bmp, int bits, int decode);
 290
 291 /* allocates output each time. len is always in bytes of binary data.
 292  * May assert (or just go wrong) if lengths are unchecked. */
 293 char *bin2hex(const unsigned char *in, int inlen);
 294 unsigned char *hex2bin(const char *in, int outlen);
 295
 296 /* Sets (and possibly dims) background from frontend default colour,
 297  * and auto-generates highlight and lowlight colours too. */
 298 void game_mkhighlight(frontend *fe, float *ret,
 299                       int background, int highlight, int lowlight);
 300 /* As above, but starts from a provided background colour rather
 301  * than the frontend default. */
 302 void game_mkhighlight_specific(frontend *fe, float *ret,
 303                                int background, int highlight, int lowlight);
 304
 305 /* Randomly shuffles an array of items. */
 306 void shuffle(void *array, int nelts, int eltsize, random_state *rs);
 307
 308 /* Draw a rectangle outline, using the drawing API's draw_line. */
 309 void draw_rect_outline(drawing *dr, int x, int y, int w, int h,
 310                        int colour);
 311
 312 /* Draw a set of rectangle corners (e.g. for a cursor display). */
 313 void draw_rect_corners(drawing *dr, int cx, int cy, int r, int col);
 314
 315 void move_cursor(int button, int *x, int *y, int maxw, int maxh, int wrap);
 316
 317 /* Used in netslide.c and sixteen.c for cursor movement around edge. */
 318 int c2pos(int w, int h, int cx, int cy);
 319 int c2diff(int w, int h, int cx, int cy, int button);
 320 void pos2c(int w, int h, int pos, int *cx, int *cy);
 321
 322 /* Draws text with an 'outline' formed by offsetting the text
 323  * by one pixel; useful for highlighting. Outline is omitted if -1. */
 324 void draw_text_outline(drawing *dr, int x, int y, int fonttype,
 325                        int fontsize, int align,
 326                        int text_colour, int outline_colour, char *text);
 327 /*
 328  * dsf.c
 329  */
 330 int *snew_dsf(int size);
 331
 332 void print_dsf(int *dsf, int size);
 333
 334 /* Return the canonical element of the equivalence class containing element
 335  * val.  If 'inverse' is non-NULL, this function will put into it a flag
 336  * indicating whether the canonical element is inverse to val. */
 337 int edsf_canonify(int *dsf, int val, int *inverse);
 338 int dsf_canonify(int *dsf, int val);
 339 int dsf_size(int *dsf, int val);
 340
 341 /* Allow the caller to specify that two elements should be in the same
 342  * equivalence class.  If 'inverse' is TRUE, the elements are actually opposite
 343  * to one another in some sense.  This function will fail an assertion if the
 344  * caller gives it self-contradictory data, ie if two elements are claimed to
 345  * be both opposite and non-opposite. */
 346 void edsf_merge(int *dsf, int v1, int v2, int inverse);
 347 void dsf_merge(int *dsf, int v1, int v2);
 348 void dsf_init(int *dsf, int len);
 349
 350 /*
 351  * tdq.c
 352  */
 353
 354 /*
 355  * Data structure implementing a 'to-do queue', a simple
 356  * de-duplicating to-do list mechanism.
 357  *
 358  * Specification: a tdq is a queue which can hold integers from 0 to
 359  * n-1, where n was some constant specified at tdq creation time. No
 360  * integer may appear in the queue's current contents more than once;
 361  * an attempt to add an already-present integer again will do nothing,
 362  * so that that integer is removed from the queue at the position
 363  * where it was _first_ inserted. The add and remove operations take
 364  * constant time.
 365  *
 366  * The idea is that you might use this in applications like solvers:
 367  * keep a tdq listing the indices of grid squares that you currently
 368  * need to process in some way. Whenever you modify a square in a way
 369  * that will require you to re-scan its neighbours, add them to the
 370  * list with tdq_add; meanwhile you're constantly taking elements off
 371  * the list when you need another square to process. In solvers where
 372  * deductions are mostly localised, this should prevent repeated
 373  * O(N^2) loops over the whole grid looking for something to do. (But
 374  * if only _most_ of the deductions are localised, then you should
 375  * respond to an empty to-do list by re-adding everything using
 376  * tdq_fill, so _then_ you rescan the whole grid looking for newly
 377  * enabled non-local deductions. Only if you've done that and emptied
 378  * the list again finding nothing new to do are you actually done.)
 379  */
 380 typedef struct tdq tdq;
 381 tdq *tdq_new(int n);
 382 void tdq_free(tdq *tdq);
 383 void tdq_add(tdq *tdq, int k);
 384 int tdq_remove(tdq *tdq);        /* returns -1 if nothing available */
 385 void tdq_fill(tdq *tdq);         /* add everything to the tdq at once */
 386
 387 /*
 388  * laydomino.c
 389  */
 390 int *domino_layout(int w, int h, random_state *rs);
 391 void domino_layout_prealloc(int w, int h, random_state *rs,
 392                             int *grid, int *grid2, int *list);
 393 /*
 394  * version.c
 395  */
 396 extern char ver[];
 397
 398 /*
 399  * random.c
 400  */
 401 random_state *random_new(char *seed, int len);
 402 random_state *random_copy(random_state *tocopy);
 403 unsigned long random_bits(random_state *state, int bits);
 404 unsigned long random_upto(random_state *state, unsigned long limit);
 405 void random_free(random_state *state);
 406 char *random_state_encode(random_state *state);
 407 random_state *random_state_decode(char *input);
 408 /* random.c also exports SHA, which occasionally comes in useful. */
 409 #if __STDC_VERSION__ >= 199901L
 410 #include <stdint.h>
 411 typedef uint32_t uint32;
 412 #elif UINT_MAX >= 4294967295L
 413 typedef unsigned int uint32;
 414 #else
 415 typedef unsigned long uint32;
 416 #endif
 417 typedef struct {
 418     uint32 h[5];
 419     unsigned char block[64];
 420     int blkused;
 421     uint32 lenhi, lenlo;
 422 } SHA_State;
 423 void SHA_Init(SHA_State *s);
 424 void SHA_Bytes(SHA_State *s, void *p, int len);
 425 void SHA_Final(SHA_State *s, unsigned char *output);
 426 void SHA_Simple(void *p, int len, unsigned char *output);
 427
 428 /*
 429  * printing.c
 430  */
 431 document *document_new(int pw, int ph, float userscale);
 432 void document_free(document *doc);
 433 void document_add_puzzle(document *doc, const game *game, game_params *par,
 434                          game_state *st, game_state *st2);
 435 void document_print(document *doc, drawing *dr);
 436
 437 /*
 438  * ps.c
 439  */
 440 psdata *ps_init(FILE *outfile, int colour);
 441 void ps_free(psdata *ps);
 442 drawing *ps_drawing_api(psdata *ps);
 443
 444 /*
 445  * combi.c: provides a structure and functions for iterating over
 446  * combinations (i.e. choosing r things out of n).
 447  */
 448 typedef struct _combi_ctx {
 449   int r, n, nleft, total;
 450   int *a;
 451 } combi_ctx;
 452
 453 combi_ctx *new_combi(int r, int n);
 454 void reset_combi(combi_ctx *combi);
 455 combi_ctx *next_combi(combi_ctx *combi); /* returns NULL for end */
 456 void free_combi(combi_ctx *combi);
 457
 458 /*
 459  * divvy.c
 460  */
 461 /* divides w*h rectangle into pieces of size k. Returns w*h dsf. */
 462 int *divvy_rectangle(int w, int h, int k, random_state *rs);
 463
 464 /*
 465  * Data structure containing the function calls and data specific
 466  * to a particular game. This is enclosed in a data structure so
 467  * that a particular platform can choose, if it wishes, to compile
 468  * all the games into a single combined executable rather than
 469  * having lots of little ones.
 470  */
 471 struct game {
 472     const char *name;
 473     const char *winhelp_topic, *htmlhelp_topic;
 474     game_params *(*default_params)(void);
 475     int (*fetch_preset)(int i, char **name, game_params **params);
 476     void (*decode_params)(game_params *, char const *string);
 477     char *(*encode_params)(game_params *, int full);
 478     void (*free_params)(game_params *params);
 479     game_params *(*dup_params)(game_params *params);
 480     int can_configure;
 481     config_item *(*configure)(game_params *params);
 482     game_params *(*custom_params)(config_item *cfg);
 483     char *(*validate_params)(game_params *params, int full);
 484     char *(*new_desc)(game_params *params, random_state *rs,
 485                       char **aux, int interactive);
 486     char *(*validate_desc)(game_params *params, char *desc);
 487     game_state *(*new_game)(midend *me, game_params *params, char *desc);
 488     game_state *(*dup_game)(game_state *state);
 489     void (*free_game)(game_state *state);
 490     int can_solve;
 491     char *(*solve)(game_state *orig, game_state *curr,
 492                    char *aux, char **error);
 493     int can_format_as_text_ever;
 494     int (*can_format_as_text_now)(game_params *params);
 495     char *(*text_format)(game_state *state);
 496     game_ui *(*new_ui)(game_state *state);
 497     void (*free_ui)(game_ui *ui);
 498     char *(*encode_ui)(game_ui *ui);
 499     void (*decode_ui)(game_ui *ui, char *encoding);
 500     void (*changed_state)(game_ui *ui, game_state *oldstate,
 501                           game_state *newstate);
 502     char *(*interpret_move)(game_state *state, game_ui *ui, game_drawstate *ds,
 503                             int x, int y, int button);
 504     game_state *(*execute_move)(game_state *state, char *move);
 505     int preferred_tilesize;
 506     void (*compute_size)(game_params *params, int tilesize, int *x, int *y);
 507     void (*set_size)(drawing *dr, game_drawstate *ds,
 508                      game_params *params, int tilesize);
 509     float *(*colours)(frontend *fe, int *ncolours);
 510     game_drawstate *(*new_drawstate)(drawing *dr, game_state *state);
 511     void (*free_drawstate)(drawing *dr, game_drawstate *ds);
 512     void (*redraw)(drawing *dr, game_drawstate *ds, game_state *oldstate,
 513                    game_state *newstate, int dir, game_ui *ui, float anim_time,
 514                    float flash_time);
 515     float (*anim_length)(game_state *oldstate, game_state *newstate, int dir,
 516                          game_ui *ui);
 517     float (*flash_length)(game_state *oldstate, game_state *newstate, int dir,
 518                           game_ui *ui);
 519     int (*status)(game_state *state);
 520     int can_print, can_print_in_colour;
 521     void (*print_size)(game_params *params, float *x, float *y);
 522     void (*print)(drawing *dr, game_state *state, int tilesize);
 523     int wants_statusbar;
 524     int is_timed;
 525     int (*timing_state)(game_state *state, game_ui *ui);
 526     int flags;
 527 };
 528
 529 /*
 530  * Data structure containing the drawing API implemented by the
 531  * front end and also by cross-platform printing modules such as
 532  * PostScript.
 533  */
 534 struct drawing_api {
 535     void (*draw_text)(void *handle, int x, int y, int fonttype, int fontsize,
 536                       int align, int colour, char *text);
 537     void (*draw_rect)(void *handle, int x, int y, int w, int h, int colour);
 538     void (*draw_line)(void *handle, int x1, int y1, int x2, int y2,
 539                       int colour);
 540     void (*draw_polygon)(void *handle, int *coords, int npoints,
 541                          int fillcolour, int outlinecolour);
 542     void (*draw_circle)(void *handle, int cx, int cy, int radius,
 543                         int fillcolour, int outlinecolour);
 544     void (*draw_update)(void *handle, int x, int y, int w, int h);
 545     void (*clip)(void *handle, int x, int y, int w, int h);
 546     void (*unclip)(void *handle);
 547     void (*start_draw)(void *handle);
 548     void (*end_draw)(void *handle);
 549     void (*status_bar)(void *handle, char *text);
 550     blitter *(*blitter_new)(void *handle, int w, int h);
 551     void (*blitter_free)(void *handle, blitter *bl);
 552     void (*blitter_save)(void *handle, blitter *bl, int x, int y);
 553     void (*blitter_load)(void *handle, blitter *bl, int x, int y);
 554     void (*begin_doc)(void *handle, int pages);
 555     void (*begin_page)(void *handle, int number);
 556     void (*begin_puzzle)(void *handle, float xm, float xc,
 557                          float ym, float yc, int pw, int ph, float wmm);
 558     void (*end_puzzle)(void *handle);
 559     void (*end_page)(void *handle, int number);
 560     void (*end_doc)(void *handle);
 561     void (*line_width)(void *handle, float width);
 562     void (*line_dotted)(void *handle, int dotted);
 563     char *(*text_fallback)(void *handle, const char *const *strings,
 564                            int nstrings);
 565     void (*draw_thick_line)(void *handle, float thickness,
 566                             float x1, float y1, float x2, float y2,
 567                             int colour);
 568 };
 569
 570 /*
 571  * For one-game-at-a-time platforms, there's a single structure
 572  * like the above, under a fixed name. For all-at-once platforms,
 573  * there's a list of all available puzzles in array form.
 574  */
 575 #ifdef COMBINED
 576 extern const game *gamelist[];
 577 extern const int gamecount;
 578 #else
 579 extern const game thegame;
 580 #endif
 581
 582 #endif /* PUZZLES_PUZZLES_H */