1 /*
2 * cube.c: Cube game.
3 */
4
5 #include <stdio.h>
6 #include <stdlib.h>
7 #include <string.h>
8 #include <assert.h>
9 #include <ctype.h>
10 #include <math.h>
11
12 #include "puzzles.h"
13
14 #define MAXVERTICES 20
15 #define MAXFACES 20
16 #define MAXORDER 4
17 struct solid {
18 int nvertices;
19 float vertices[MAXVERTICES * 3]; /* 3*npoints coordinates */
20 int order;
21 int nfaces;
22 int faces[MAXFACES * MAXORDER]; /* order*nfaces point indices */
23 float normals[MAXFACES * 3]; /* 3*npoints vector components */
24 float shear; /* isometric shear for nice drawing */
25 float border; /* border required around arena */
26 };
27
28 static const struct solid s_tetrahedron = {
29 4,
30 {
31 0.0F, -0.57735026919F, -0.20412414523F,
32 -0.5F, 0.28867513459F, -0.20412414523F,
33 0.0F, -0.0F, 0.6123724357F,
34 0.5F, 0.28867513459F, -0.20412414523F,
35 },
36 3, 4,
37 {
38 0,2,1, 3,1,2, 2,0,3, 1,3,0
39 },
40 {
41 -0.816496580928F, -0.471404520791F, 0.333333333334F,
42 0.0F, 0.942809041583F, 0.333333333333F,
43 0.816496580928F, -0.471404520791F, 0.333333333334F,
44 0.0F, 0.0F, -1.0F,
45 },
46 0.0F, 0.3F
47 };
48
49 static const struct solid s_cube = {
50 8,
51 {
52 -0.5F,-0.5F,-0.5F, -0.5F,-0.5F,+0.5F,
53 -0.5F,+0.5F,-0.5F, -0.5F,+0.5F,+0.5F,
54 +0.5F,-0.5F,-0.5F, +0.5F,-0.5F,+0.5F,
55 +0.5F,+0.5F,-0.5F, +0.5F,+0.5F,+0.5F,
56 },
57 4, 6,
58 {
59 0,1,3,2, 1,5,7,3, 5,4,6,7, 4,0,2,6, 0,4,5,1, 3,7,6,2
60 },
61 {
62 -1.0F,0.0F,0.0F, 0.0F,0.0F,+1.0F,
63 +1.0F,0.0F,0.0F, 0.0F,0.0F,-1.0F,
64 0.0F,-1.0F,0.0F, 0.0F,+1.0F,0.0F
65 },
66 0.3F, 0.5F
67 };
68
69 static const struct solid s_octahedron = {
70 6,
71 {
72 -0.5F, -0.28867513459472505F, 0.4082482904638664F,
73 0.5F, 0.28867513459472505F, -0.4082482904638664F,
74 -0.5F, 0.28867513459472505F, -0.4082482904638664F,
75 0.5F, -0.28867513459472505F, 0.4082482904638664F,
76 0.0F, -0.57735026918945009F, -0.4082482904638664F,
77 0.0F, 0.57735026918945009F, 0.4082482904638664F,
78 },
79 3, 8,
80 {
81 4,0,2, 0,5,2, 0,4,3, 5,0,3, 1,4,2, 5,1,2, 4,1,3, 1,5,3
82 },
83 {
84 -0.816496580928F, -0.471404520791F, -0.333333333334F,
85 -0.816496580928F, 0.471404520791F, 0.333333333334F,
86 0.0F, -0.942809041583F, 0.333333333333F,
87 0.0F, 0.0F, 1.0F,
88 0.0F, 0.0F, -1.0F,
89 0.0F, 0.942809041583F, -0.333333333333F,
90 0.816496580928F, -0.471404520791F, -0.333333333334F,
91 0.816496580928F, 0.471404520791F, 0.333333333334F,
92 },
93 0.0F, 0.5F
94 };
95
96 static const struct solid s_icosahedron = {
97 12,
98 {
99 0.0F, 0.57735026919F, 0.75576131408F,
100 0.0F, -0.93417235896F, 0.17841104489F,
101 0.0F, 0.93417235896F, -0.17841104489F,
102 0.0F, -0.57735026919F, -0.75576131408F,
103 -0.5F, -0.28867513459F, 0.75576131408F,
104 -0.5F, 0.28867513459F, -0.75576131408F,
105 0.5F, -0.28867513459F, 0.75576131408F,
106 0.5F, 0.28867513459F, -0.75576131408F,
107 -0.80901699437F, 0.46708617948F, 0.17841104489F,
108 0.80901699437F, 0.46708617948F, 0.17841104489F,
109 -0.80901699437F, -0.46708617948F, -0.17841104489F,
110 0.80901699437F, -0.46708617948F, -0.17841104489F,
111 },
112 3, 20,
113 {
114 8,0,2, 0,9,2, 1,10,3, 11,1,3, 0,4,6,
115 4,1,6, 5,2,7, 3,5,7, 4,8,10, 8,5,10,
116 9,6,11, 7,9,11, 0,8,4, 9,0,6, 10,1,4,
117 1,11,6, 8,2,5, 2,9,7, 3,10,5, 11,3,7,
118 },
119 {
120 -0.356822089773F, 0.87267799625F, 0.333333333333F,
121 0.356822089773F, 0.87267799625F, 0.333333333333F,
122 -0.356822089773F, -0.87267799625F, -0.333333333333F,
123 0.356822089773F, -0.87267799625F, -0.333333333333F,
124 -0.0F, 0.0F, 1.0F,
125 0.0F, -0.666666666667F, 0.745355992501F,
126 0.0F, 0.666666666667F, -0.745355992501F,
127 0.0F, 0.0F, -1.0F,
128 -0.934172358963F, -0.12732200375F, 0.333333333333F,
129 -0.934172358963F, 0.12732200375F, -0.333333333333F,
130 0.934172358963F, -0.12732200375F, 0.333333333333F,
131 0.934172358963F, 0.12732200375F, -0.333333333333F,
132 -0.57735026919F, 0.333333333334F, 0.745355992501F,
133 0.57735026919F, 0.333333333334F, 0.745355992501F,
134 -0.57735026919F, -0.745355992501F, 0.333333333334F,
135 0.57735026919F, -0.745355992501F, 0.333333333334F,
136 -0.57735026919F, 0.745355992501F, -0.333333333334F,
137 0.57735026919F, 0.745355992501F, -0.333333333334F,
138 -0.57735026919F, -0.333333333334F, -0.745355992501F,
139 0.57735026919F, -0.333333333334F, -0.745355992501F,
140 },
141 0.0F, 0.8F
142 };
143
144 enum {
145 TETRAHEDRON, CUBE, OCTAHEDRON, ICOSAHEDRON
146 };
147 static const struct solid *solids[] = {
148 &s_tetrahedron, &s_cube, &s_octahedron, &s_icosahedron
149 };
150
151 enum {
152 COL_BACKGROUND,
153 COL_BORDER,
154 COL_BLUE,
155 NCOLOURS
156 };
157
158 enum { LEFT, RIGHT, UP, DOWN, UP_LEFT, UP_RIGHT, DOWN_LEFT, DOWN_RIGHT };
159
160 #define PREFERRED_GRID_SCALE 48
161 #define GRID_SCALE (ds->gridscale)
162 #define ROLLTIME 0.13F
163
164 #define SQ(x) ( (x) * (x) )
165
166 #define MATMUL(ra,m,a) do { \
167 float rx, ry, rz, xx = (a)[0], yy = (a)[1], zz = (a)[2], *mat = (m); \
168 rx = mat[0] * xx + mat[3] * yy + mat[6] * zz; \
169 ry = mat[1] * xx + mat[4] * yy + mat[7] * zz; \
170 rz = mat[2] * xx + mat[5] * yy + mat[8] * zz; \
171 (ra)[0] = rx; (ra)[1] = ry; (ra)[2] = rz; \
172 } while (0)
173
174 #define APPROXEQ(x,y) ( SQ(x-y) < 0.1 )
175
176 struct grid_square {
177 float x, y;
178 int npoints;
179 float points[8]; /* maximum */
180 int directions[8]; /* bit masks showing point pairs */
181 bool flip;
182 int tetra_class;
183 };
184
185 struct game_params {
186 int solid;
187 /*
188 * Grid dimensions. For a square grid these are width and
189 * height respectively; otherwise the grid is a hexagon, with
190 * the top side and the two lower diagonals having length d1
191 * and the remaining three sides having length d2 (so that
192 * d1==d2 gives a regular hexagon, and d2==0 gives a triangle).
193 */
194 int d1, d2;
195 };
196
197 typedef struct game_grid game_grid;
198 struct game_grid {
199 int refcount;
200 struct grid_square *squares;
201 int nsquares;
202 };
203
204 #define SET_SQUARE(state, i, val) \
205 ((state)->bluemask[(i)/32] &= ~(1 << ((i)%32)), \
206 (state)->bluemask[(i)/32] |= ((!!val) << ((i)%32)))
207 #define GET_SQUARE(state, i) \
208 (((state)->bluemask[(i)/32] >> ((i)%32)) & 1)
209
210 struct game_state {
211 struct game_params params;
212 const struct solid *solid;
213 int *facecolours;
214 game_grid *grid;
215 unsigned long *bluemask;
216 int current; /* index of current grid square */
217 int sgkey[2]; /* key-point indices into grid sq */
218 int dgkey[2]; /* key-point indices into grid sq */
219 int spkey[2]; /* key-point indices into polyhedron */
220 int dpkey[2]; /* key-point indices into polyhedron */
221 int previous;
222 float angle;
223 int completed; /* stores move count at completion */
224 int movecount;
225 };
226
default_params(void)227 static game_params *default_params(void)
228 {
229 game_params *ret = snew(game_params);
230
231 ret->solid = CUBE;
232 ret->d1 = 4;
233 ret->d2 = 4;
234
235 return ret;
236 }
237
game_fetch_preset(int i,char ** name,game_params ** params)238 static bool game_fetch_preset(int i, char **name, game_params **params)
239 {
240 game_params *ret = snew(game_params);
241 const char *str;
242
243 switch (i) {
244 case 0:
245 str = "Cube";
246 ret->solid = CUBE;
247 ret->d1 = 4;
248 ret->d2 = 4;
249 break;
250 case 1:
251 str = "Tetrahedron";
252 ret->solid = TETRAHEDRON;
253 ret->d1 = 1;
254 ret->d2 = 2;
255 break;
256 case 2:
257 str = "Octahedron";
258 ret->solid = OCTAHEDRON;
259 ret->d1 = 2;
260 ret->d2 = 2;
261 break;
262 case 3:
263 str = "Icosahedron";
264 ret->solid = ICOSAHEDRON;
265 ret->d1 = 3;
266 ret->d2 = 3;
267 break;
268 default:
269 sfree(ret);
270 return false;
271 }
272
273 *name = dupstr(str);
274 *params = ret;
275 return true;
276 }
277
free_params(game_params * params)278 static void free_params(game_params *params)
279 {
280 sfree(params);
281 }
282
dup_params(const game_params * params)283 static game_params *dup_params(const game_params *params)
284 {
285 game_params *ret = snew(game_params);
286 *ret = *params; /* structure copy */
287 return ret;
288 }
289
decode_params(game_params * ret,char const * string)290 static void decode_params(game_params *ret, char const *string)
291 {
292 switch (*string) {
293 case 't': ret->solid = TETRAHEDRON; string++; break;
294 case 'c': ret->solid = CUBE; string++; break;
295 case 'o': ret->solid = OCTAHEDRON; string++; break;
296 case 'i': ret->solid = ICOSAHEDRON; string++; break;
297 default: break;
298 }
299 ret->d1 = ret->d2 = atoi(string);
300 while (*string && isdigit((unsigned char)*string)) string++;
301 if (*string == 'x') {
302 string++;
303 ret->d2 = atoi(string);
304 }
305 }
306
encode_params(const game_params * params,bool full)307 static char *encode_params(const game_params *params, bool full)
308 {
309 char data[256];
310
311 assert(params->solid >= 0 && params->solid < 4);
312 sprintf(data, "%c%dx%d", "tcoi"[params->solid], params->d1, params->d2);
313
314 return dupstr(data);
315 }
316 typedef void (*egc_callback)(void *, struct grid_square *);
317
enum_grid_squares(const game_params * params,egc_callback callback,void * ctx)318 static void enum_grid_squares(const game_params *params, egc_callback callback,
319 void *ctx)
320 {
321 const struct solid *solid = solids[params->solid];
322
323 if (solid->order == 4) {
324 int x, y;
325
326 for (y = 0; y < params->d2; y++)
327 for (x = 0; x < params->d1; x++) {
328 struct grid_square sq;
329
330 sq.x = (float)x;
331 sq.y = (float)y;
332 sq.points[0] = x - 0.5F;
333 sq.points[1] = y - 0.5F;
334 sq.points[2] = x - 0.5F;
335 sq.points[3] = y + 0.5F;
336 sq.points[4] = x + 0.5F;
337 sq.points[5] = y + 0.5F;
338 sq.points[6] = x + 0.5F;
339 sq.points[7] = y - 0.5F;
340 sq.npoints = 4;
341
342 sq.directions[LEFT] = 0x03; /* 0,1 */
343 sq.directions[RIGHT] = 0x0C; /* 2,3 */
344 sq.directions[UP] = 0x09; /* 0,3 */
345 sq.directions[DOWN] = 0x06; /* 1,2 */
346 sq.directions[UP_LEFT] = 0; /* no diagonals in a square */
347 sq.directions[UP_RIGHT] = 0; /* no diagonals in a square */
348 sq.directions[DOWN_LEFT] = 0; /* no diagonals in a square */
349 sq.directions[DOWN_RIGHT] = 0; /* no diagonals in a square */
350
351 sq.flip = false;
352
353 /*
354 * This is supremely irrelevant, but just to avoid
355 * having any uninitialised structure members...
356 */
357 sq.tetra_class = 0;
358
359 callback(ctx, &sq);
360 }
361 } else {
362 int row, rowlen, other, i, firstix = -1;
363 float theight = (float)(sqrt(3) / 2.0);
364
365 for (row = 0; row < params->d1 + params->d2; row++) {
366 if (row < params->d2) {
367 other = +1;
368 rowlen = row + params->d1;
369 } else {
370 other = -1;
371 rowlen = 2*params->d2 + params->d1 - row;
372 }
373
374 /*
375 * There are `rowlen' down-pointing triangles.
376 */
377 for (i = 0; i < rowlen; i++) {
378 struct grid_square sq;
379 int ix;
380 float x, y;
381
382 ix = (2 * i - (rowlen-1));
383 x = ix * 0.5F;
384 y = theight * row;
385 sq.x = x;
386 sq.y = y + theight / 3;
387 sq.points[0] = x - 0.5F;
388 sq.points[1] = y;
389 sq.points[2] = x;
390 sq.points[3] = y + theight;
391 sq.points[4] = x + 0.5F;
392 sq.points[5] = y;
393 sq.npoints = 3;
394
395 sq.directions[LEFT] = 0x03; /* 0,1 */
396 sq.directions[RIGHT] = 0x06; /* 1,2 */
397 sq.directions[UP] = 0x05; /* 0,2 */
398 sq.directions[DOWN] = 0; /* invalid move */
399
400 /*
401 * Down-pointing triangle: both the up diagonals go
402 * up, and the down ones go left and right.
403 */
404 sq.directions[UP_LEFT] = sq.directions[UP_RIGHT] =
405 sq.directions[UP];
406 sq.directions[DOWN_LEFT] = sq.directions[LEFT];
407 sq.directions[DOWN_RIGHT] = sq.directions[RIGHT];
408
409 sq.flip = true;
410
411 if (firstix < 0)
412 firstix = ix & 3;
413 ix -= firstix;
414 sq.tetra_class = ((row+(ix&1)) & 2) ^ (ix & 3);
415
416 callback(ctx, &sq);
417 }
418
419 /*
420 * There are `rowlen+other' up-pointing triangles.
421 */
422 for (i = 0; i < rowlen+other; i++) {
423 struct grid_square sq;
424 int ix;
425 float x, y;
426
427 ix = (2 * i - (rowlen+other-1));
428 x = ix * 0.5F;
429 y = theight * row;
430 sq.x = x;
431 sq.y = y + 2*theight / 3;
432 sq.points[0] = x + 0.5F;
433 sq.points[1] = y + theight;
434 sq.points[2] = x;
435 sq.points[3] = y;
436 sq.points[4] = x - 0.5F;
437 sq.points[5] = y + theight;
438 sq.npoints = 3;
439
440 sq.directions[LEFT] = 0x06; /* 1,2 */
441 sq.directions[RIGHT] = 0x03; /* 0,1 */
442 sq.directions[DOWN] = 0x05; /* 0,2 */
443 sq.directions[UP] = 0; /* invalid move */
444
445 /*
446 * Up-pointing triangle: both the down diagonals go
447 * down, and the up ones go left and right.
448 */
449 sq.directions[DOWN_LEFT] = sq.directions[DOWN_RIGHT] =
450 sq.directions[DOWN];
451 sq.directions[UP_LEFT] = sq.directions[LEFT];
452 sq.directions[UP_RIGHT] = sq.directions[RIGHT];
453
454 sq.flip = false;
455
456 if (firstix < 0)
457 firstix = (ix - 1) & 3;
458 ix -= firstix;
459 sq.tetra_class = ((row+(ix&1)) & 2) ^ (ix & 3);
460
461 callback(ctx, &sq);
462 }
463 }
464 }
465 }
466
grid_area(int d1,int d2,int order)467 static int grid_area(int d1, int d2, int order)
468 {
469 /*
470 * An NxM grid of squares has NM squares in it.
471 *
472 * A grid of triangles with dimensions A and B has a total of
473 * A^2 + B^2 + 4AB triangles in it. (You can divide it up into
474 * a side-A triangle containing A^2 subtriangles, a side-B
475 * triangle containing B^2, and two congruent parallelograms,
476 * each with side lengths A and B, each therefore containing AB
477 * two-triangle rhombuses.)
478 */
479 if (order == 4)
480 return d1 * d2;
481 else
482 return d1*d1 + d2*d2 + 4*d1*d2;
483 }
484
game_configure(const game_params * params)485 static config_item *game_configure(const game_params *params)
486 {
487 config_item *ret = snewn(4, config_item);
488 char buf[80];
489
490 ret[0].name = "Type of solid";
491 ret[0].type = C_CHOICES;
492 ret[0].u.choices.choicenames = ":Tetrahedron:Cube:Octahedron:Icosahedron";
493 ret[0].u.choices.selected = params->solid;
494
495 ret[1].name = "Width / top";
496 ret[1].type = C_STRING;
497 sprintf(buf, "%d", params->d1);
498 ret[1].u.string.sval = dupstr(buf);
499
500 ret[2].name = "Height / bottom";
501 ret[2].type = C_STRING;
502 sprintf(buf, "%d", params->d2);
503 ret[2].u.string.sval = dupstr(buf);
504
505 ret[3].name = NULL;
506 ret[3].type = C_END;
507
508 return ret;
509 }
510
custom_params(const config_item * cfg)511 static game_params *custom_params(const config_item *cfg)
512 {
513 game_params *ret = snew(game_params);
514
515 ret->solid = cfg[0].u.choices.selected;
516 ret->d1 = atoi(cfg[1].u.string.sval);
517 ret->d2 = atoi(cfg[2].u.string.sval);
518
519 return ret;
520 }
521
count_grid_square_callback(void * ctx,struct grid_square * sq)522 static void count_grid_square_callback(void *ctx, struct grid_square *sq)
523 {
524 int *classes = (int *)ctx;
525 int thisclass;
526
527 if (classes[4] == 4)
528 thisclass = sq->tetra_class;
529 else if (classes[4] == 2)
530 thisclass = sq->flip;
531 else
532 thisclass = 0;
533
534 classes[thisclass]++;
535 }
536
validate_params(const game_params * params,bool full)537 static const char *validate_params(const game_params *params, bool full)
538 {
539 int classes[5];
540 int i;
541
542 if (params->solid < 0 || params->solid >= lenof(solids))
543 return "Unrecognised solid type";
544
545 if (solids[params->solid]->order == 4) {
546 if (params->d1 <= 1 || params->d2 <= 1)
547 return "Both grid dimensions must be greater than one";
548 } else {
549 if (params->d1 <= 0 && params->d2 <= 0)
550 return "At least one grid dimension must be greater than zero";
551 }
552
553 for (i = 0; i < 4; i++)
554 classes[i] = 0;
555 if (params->solid == TETRAHEDRON)
556 classes[4] = 4;
557 else if (params->solid == OCTAHEDRON)
558 classes[4] = 2;
559 else
560 classes[4] = 1;
561 enum_grid_squares(params, count_grid_square_callback, classes);
562
563 for (i = 0; i < classes[4]; i++)
564 if (classes[i] < solids[params->solid]->nfaces / classes[4])
565 return "Not enough grid space to place all blue faces";
566
567 if (grid_area(params->d1, params->d2, solids[params->solid]->order) <
568 solids[params->solid]->nfaces + 1)
569 return "Not enough space to place the solid on an empty square";
570
571 return NULL;
572 }
573
574 struct grid_data {
575 int *gridptrs[4];
576 int nsquares[4];
577 int nclasses;
578 int squareindex;
579 };
580
classify_grid_square_callback(void * ctx,struct grid_square * sq)581 static void classify_grid_square_callback(void *ctx, struct grid_square *sq)
582 {
583 struct grid_data *data = (struct grid_data *)ctx;
584 int thisclass;
585
586 if (data->nclasses == 4)
587 thisclass = sq->tetra_class;
588 else if (data->nclasses == 2)
589 thisclass = sq->flip;
590 else
591 thisclass = 0;
592
593 data->gridptrs[thisclass][data->nsquares[thisclass]++] =
594 data->squareindex++;
595 }
596
new_game_desc(const game_params * params,random_state * rs,char ** aux,bool interactive)597 static char *new_game_desc(const game_params *params, random_state *rs,
598 char **aux, bool interactive)
599 {
600 struct grid_data data;
601 int i, j, k, m, area, facesperclass;
602 bool *flags;
603 char *desc, *p;
604
605 /*
606 * Enumerate the grid squares, dividing them into equivalence
607 * classes as appropriate. (For the tetrahedron, there is one
608 * equivalence class for each face; for the octahedron there
609 * are two classes; for the other two solids there's only one.)
610 */
611
612 area = grid_area(params->d1, params->d2, solids[params->solid]->order);
613 if (params->solid == TETRAHEDRON)
614 data.nclasses = 4;
615 else if (params->solid == OCTAHEDRON)
616 data.nclasses = 2;
617 else
618 data.nclasses = 1;
619 data.gridptrs[0] = snewn(data.nclasses * area, int);
620 for (i = 0; i < data.nclasses; i++) {
621 data.gridptrs[i] = data.gridptrs[0] + i * area;
622 data.nsquares[i] = 0;
623 }
624 data.squareindex = 0;
625 enum_grid_squares(params, classify_grid_square_callback, &data);
626
627 facesperclass = solids[params->solid]->nfaces / data.nclasses;
628
629 for (i = 0; i < data.nclasses; i++)
630 assert(data.nsquares[i] >= facesperclass);
631 assert(data.squareindex == area);
632
633 /*
634 * So now we know how many faces to allocate in each class. Get
635 * on with it.
636 */
637 flags = snewn(area, bool);
638 for (i = 0; i < area; i++)
639 flags[i] = false;
640
641 for (i = 0; i < data.nclasses; i++) {
642 for (j = 0; j < facesperclass; j++) {
643 int n = random_upto(rs, data.nsquares[i]);
644
645 assert(!flags[data.gridptrs[i][n]]);
646 flags[data.gridptrs[i][n]] = true;
647
648 /*
649 * Move everything else up the array. I ought to use a
650 * better data structure for this, but for such small
651 * numbers it hardly seems worth the effort.
652 */
653 while (n < data.nsquares[i]-1) {
654 data.gridptrs[i][n] = data.gridptrs[i][n+1];
655 n++;
656 }
657 data.nsquares[i]--;
658 }
659 }
660
661 /*
662 * Now we know precisely which squares are blue. Encode this
663 * information in hex. While we're looping over this, collect
664 * the non-blue squares into a list in the now-unused gridptrs
665 * array.
666 */
667 desc = snewn(area / 4 + 40, char);
668 p = desc;
669 j = 0;
670 k = 8;
671 m = 0;
672 for (i = 0; i < area; i++) {
673 if (flags[i]) {
674 j |= k;
675 } else {
676 data.gridptrs[0][m++] = i;
677 }
678 k >>= 1;
679 if (!k) {
680 *p++ = "0123456789ABCDEF"[j];
681 k = 8;
682 j = 0;
683 }
684 }
685 if (k != 8)
686 *p++ = "0123456789ABCDEF"[j];
687
688 /*
689 * Choose a non-blue square for the polyhedron.
690 */
691 sprintf(p, ",%d", data.gridptrs[0][random_upto(rs, m)]);
692
693 sfree(data.gridptrs[0]);
694 sfree(flags);
695
696 return desc;
697 }
698
add_grid_square_callback(void * ctx,struct grid_square * sq)699 static void add_grid_square_callback(void *ctx, struct grid_square *sq)
700 {
701 game_grid *grid = (game_grid *)ctx;
702
703 grid->squares[grid->nsquares++] = *sq; /* structure copy */
704 }
705
lowest_face(const struct solid * solid)706 static int lowest_face(const struct solid *solid)
707 {
708 int i, j, best;
709 float zmin;
710
711 best = 0;
712 zmin = 0.0;
713 for (i = 0; i < solid->nfaces; i++) {
714 float z = 0;
715
716 for (j = 0; j < solid->order; j++) {
717 int f = solid->faces[i*solid->order + j];
718 z += solid->vertices[f*3+2];
719 }
720
721 if (i == 0 || zmin > z) {
722 zmin = z;
723 best = i;
724 }
725 }
726
727 return best;
728 }
729
align_poly(const struct solid * solid,struct grid_square * sq,int * pkey)730 static bool align_poly(const struct solid *solid, struct grid_square *sq,
731 int *pkey)
732 {
733 float zmin;
734 int i, j;
735 int flip = (sq->flip ? -1 : +1);
736
737 /*
738 * First, find the lowest z-coordinate present in the solid.
739 */
740 zmin = 0.0;
741 for (i = 0; i < solid->nvertices; i++)
742 if (zmin > solid->vertices[i*3+2])
743 zmin = solid->vertices[i*3+2];
744
745 /*
746 * Now go round the grid square. For each point in the grid
747 * square, we're looking for a point of the polyhedron with the
748 * same x- and y-coordinates (relative to the square's centre),
749 * and z-coordinate equal to zmin (near enough).
750 */
751 for (j = 0; j < sq->npoints; j++) {
752 int matches, index;
753
754 matches = 0;
755 index = -1;
756
757 for (i = 0; i < solid->nvertices; i++) {
758 float dist = 0;
759
760 dist += SQ(solid->vertices[i*3+0] * flip - sq->points[j*2+0] + sq->x);
761 dist += SQ(solid->vertices[i*3+1] * flip - sq->points[j*2+1] + sq->y);
762 dist += SQ(solid->vertices[i*3+2] - zmin);
763
764 if (dist < 0.1) {
765 matches++;
766 index = i;
767 }
768 }
769
770 if (matches != 1 || index < 0)
771 return false;
772 pkey[j] = index;
773 }
774
775 return true;
776 }
777
flip_poly(struct solid * solid,bool flip)778 static void flip_poly(struct solid *solid, bool flip)
779 {
780 int i;
781
782 if (flip) {
783 for (i = 0; i < solid->nvertices; i++) {
784 solid->vertices[i*3+0] *= -1;
785 solid->vertices[i*3+1] *= -1;
786 }
787 for (i = 0; i < solid->nfaces; i++) {
788 solid->normals[i*3+0] *= -1;
789 solid->normals[i*3+1] *= -1;
790 }
791 }
792 }
793
transform_poly(const struct solid * solid,bool flip,int key0,int key1,float angle)794 static struct solid *transform_poly(const struct solid *solid, bool flip,
795 int key0, int key1, float angle)
796 {
797 struct solid *ret = snew(struct solid);
798 float vx, vy, ax, ay;
799 float vmatrix[9], amatrix[9], vmatrix2[9];
800 int i;
801
802 *ret = *solid; /* structure copy */
803
804 flip_poly(ret, flip);
805
806 /*
807 * Now rotate the polyhedron through the given angle. We must
808 * rotate about the Z-axis to bring the two vertices key0 and
809 * key1 into horizontal alignment, then rotate about the
810 * X-axis, then rotate back again.
811 */
812 vx = ret->vertices[key1*3+0] - ret->vertices[key0*3+0];
813 vy = ret->vertices[key1*3+1] - ret->vertices[key0*3+1];
814 assert(APPROXEQ(vx*vx + vy*vy, 1.0));
815
816 vmatrix[0] = vx; vmatrix[3] = vy; vmatrix[6] = 0;
817 vmatrix[1] = -vy; vmatrix[4] = vx; vmatrix[7] = 0;
818 vmatrix[2] = 0; vmatrix[5] = 0; vmatrix[8] = 1;
819
820 ax = (float)cos(angle);
821 ay = (float)sin(angle);
822
823 amatrix[0] = 1; amatrix[3] = 0; amatrix[6] = 0;
824 amatrix[1] = 0; amatrix[4] = ax; amatrix[7] = ay;
825 amatrix[2] = 0; amatrix[5] = -ay; amatrix[8] = ax;
826
827 memcpy(vmatrix2, vmatrix, sizeof(vmatrix));
828 vmatrix2[1] = vy;
829 vmatrix2[3] = -vy;
830
831 for (i = 0; i < ret->nvertices; i++) {
832 MATMUL(ret->vertices + 3*i, vmatrix, ret->vertices + 3*i);
833 MATMUL(ret->vertices + 3*i, amatrix, ret->vertices + 3*i);
834 MATMUL(ret->vertices + 3*i, vmatrix2, ret->vertices + 3*i);
835 }
836 for (i = 0; i < ret->nfaces; i++) {
837 MATMUL(ret->normals + 3*i, vmatrix, ret->normals + 3*i);
838 MATMUL(ret->normals + 3*i, amatrix, ret->normals + 3*i);
839 MATMUL(ret->normals + 3*i, vmatrix2, ret->normals + 3*i);
840 }
841
842 return ret;
843 }
844
validate_desc(const game_params * params,const char * desc)845 static const char *validate_desc(const game_params *params, const char *desc)
846 {
847 int area = grid_area(params->d1, params->d2, solids[params->solid]->order);
848 int i, j;
849
850 i = (area + 3) / 4;
851 for (j = 0; j < i; j++) {
852 int c = desc[j];
853 if (c >= '0' && c <= '9') continue;
854 if (c >= 'A' && c <= 'F') continue;
855 if (c >= 'a' && c <= 'f') continue;
856 return "Not enough hex digits at start of string";
857 /* NB if desc[j]=='\0' that will also be caught here, so we're safe */
858 }
859
860 if (desc[i] != ',')
861 return "Expected ',' after hex digits";
862
863 i++;
864 do {
865 if (desc[i] < '0' || desc[i] > '9')
866 return "Expected decimal integer after ','";
867 i++;
868 } while (desc[i]);
869
870 return NULL;
871 }
872
new_game(midend * me,const game_params * params,const char * desc)873 static game_state *new_game(midend *me, const game_params *params,
874 const char *desc)
875 {
876 game_grid *grid = snew(game_grid);
877 game_state *state = snew(game_state);
878 int area;
879
880 state->params = *params; /* structure copy */
881 state->solid = solids[params->solid];
882
883 area = grid_area(params->d1, params->d2, state->solid->order);
884 grid->squares = snewn(area, struct grid_square);
885 grid->nsquares = 0;
886 enum_grid_squares(params, add_grid_square_callback, grid);
887 assert(grid->nsquares == area);
888 state->grid = grid;
889 grid->refcount = 1;
890
891 state->facecolours = snewn(state->solid->nfaces, int);
892 memset(state->facecolours, 0, state->solid->nfaces * sizeof(int));
893
894 state->bluemask = snewn((state->grid->nsquares + 31) / 32, unsigned long);
895 memset(state->bluemask, 0, (state->grid->nsquares + 31) / 32 *
896 sizeof(unsigned long));
897
898 /*
899 * Set up the blue squares and polyhedron position according to
900 * the game description.
901 */
902 {
903 const char *p = desc;
904 int i, j, v;
905
906 j = 8;
907 v = 0;
908 for (i = 0; i < state->grid->nsquares; i++) {
909 if (j == 8) {
910 v = *p++;
911 if (v >= '0' && v <= '9')
912 v -= '0';
913 else if (v >= 'A' && v <= 'F')
914 v -= 'A' - 10;
915 else if (v >= 'a' && v <= 'f')
916 v -= 'a' - 10;
917 else
918 break;
919 }
920 if (v & j)
921 SET_SQUARE(state, i, true);
922 j >>= 1;
923 if (j == 0)
924 j = 8;
925 }
926
927 if (*p == ',')
928 p++;
929
930 state->current = atoi(p);
931 if (state->current < 0 || state->current >= state->grid->nsquares)
932 state->current = 0; /* got to do _something_ */
933 }
934
935 /*
936 * Align the polyhedron with its grid square and determine
937 * initial key points.
938 */
939 {
940 int pkey[4];
941 bool ret;
942
943 ret = align_poly(state->solid, &state->grid->squares[state->current], pkey);
944 assert(ret);
945
946 state->dpkey[0] = state->spkey[0] = pkey[0];
947 state->dpkey[1] = state->spkey[0] = pkey[1];
948 state->dgkey[0] = state->sgkey[0] = 0;
949 state->dgkey[1] = state->sgkey[0] = 1;
950 }
951
952 state->previous = state->current;
953 state->angle = 0.0;
954 state->completed = 0;
955 state->movecount = 0;
956
957 return state;
958 }
959
dup_game(const game_state * state)960 static game_state *dup_game(const game_state *state)
961 {
962 game_state *ret = snew(game_state);
963
964 ret->params = state->params; /* structure copy */
965 ret->solid = state->solid;
966 ret->facecolours = snewn(ret->solid->nfaces, int);
967 memcpy(ret->facecolours, state->facecolours,
968 ret->solid->nfaces * sizeof(int));
969 ret->current = state->current;
970 ret->grid = state->grid;
971 ret->grid->refcount++;
972 ret->bluemask = snewn((ret->grid->nsquares + 31) / 32, unsigned long);
973 memcpy(ret->bluemask, state->bluemask, (ret->grid->nsquares + 31) / 32 *
974 sizeof(unsigned long));
975 ret->dpkey[0] = state->dpkey[0];
976 ret->dpkey[1] = state->dpkey[1];
977 ret->dgkey[0] = state->dgkey[0];
978 ret->dgkey[1] = state->dgkey[1];
979 ret->spkey[0] = state->spkey[0];
980 ret->spkey[1] = state->spkey[1];
981 ret->sgkey[0] = state->sgkey[0];
982 ret->sgkey[1] = state->sgkey[1];
983 ret->previous = state->previous;
984 ret->angle = state->angle;
985 ret->completed = state->completed;
986 ret->movecount = state->movecount;
987
988 return ret;
989 }
990
free_game(game_state * state)991 static void free_game(game_state *state)
992 {
993 if (--state->grid->refcount <= 0) {
994 sfree(state->grid->squares);
995 sfree(state->grid);
996 }
997 sfree(state->bluemask);
998 sfree(state->facecolours);
999 sfree(state);
1000 }
1001
solve_game(const game_state * state,const game_state * currstate,const char * aux,const char ** error)1002 static char *solve_game(const game_state *state, const game_state *currstate,
1003 const char *aux, const char **error)
1004 {
1005 return NULL;
1006 }
1007
game_can_format_as_text_now(const game_params * params)1008 static bool game_can_format_as_text_now(const game_params *params)
1009 {
1010 return true;
1011 }
1012
game_text_format(const game_state * state)1013 static char *game_text_format(const game_state *state)
1014 {
1015 return NULL;
1016 }
1017
new_ui(const game_state * state)1018 static game_ui *new_ui(const game_state *state)
1019 {
1020 return NULL;
1021 }
1022
free_ui(game_ui * ui)1023 static void free_ui(game_ui *ui)
1024 {
1025 }
1026
encode_ui(const game_ui * ui)1027 static char *encode_ui(const game_ui *ui)
1028 {
1029 return NULL;
1030 }
1031
decode_ui(game_ui * ui,const char * encoding)1032 static void decode_ui(game_ui *ui, const char *encoding)
1033 {
1034 }
1035
game_changed_state(game_ui * ui,const game_state * oldstate,const game_state * newstate)1036 static void game_changed_state(game_ui *ui, const game_state *oldstate,
1037 const game_state *newstate)
1038 {
1039 }
1040
1041 struct game_drawstate {
1042 float gridscale;
1043 int ox, oy; /* pixel position of float origin */
1044 };
1045
1046 /*
1047 * Code shared between interpret_move() and execute_move().
1048 */
find_move_dest(const game_state * from,int direction,int * skey,int * dkey)1049 static int find_move_dest(const game_state *from, int direction,
1050 int *skey, int *dkey)
1051 {
1052 int mask, dest, i, j;
1053 float points[4];
1054
1055 /*
1056 * Find the two points in the current grid square which
1057 * correspond to this move.
1058 */
1059 mask = from->grid->squares[from->current].directions[direction];
1060 if (mask == 0)
1061 return -1;
1062 for (i = j = 0; i < from->grid->squares[from->current].npoints; i++)
1063 if (mask & (1 << i)) {
1064 points[j*2] = from->grid->squares[from->current].points[i*2];
1065 points[j*2+1] = from->grid->squares[from->current].points[i*2+1];
1066 skey[j] = i;
1067 j++;
1068 }
1069 assert(j == 2);
1070
1071 /*
1072 * Now find the other grid square which shares those points.
1073 * This is our move destination.
1074 */
1075 dest = -1;
1076 for (i = 0; i < from->grid->nsquares; i++)
1077 if (i != from->current) {
1078 int match = 0;
1079 float dist;
1080
1081 for (j = 0; j < from->grid->squares[i].npoints; j++) {
1082 dist = (SQ(from->grid->squares[i].points[j*2] - points[0]) +
1083 SQ(from->grid->squares[i].points[j*2+1] - points[1]));
1084 if (dist < 0.1)
1085 dkey[match++] = j;
1086 dist = (SQ(from->grid->squares[i].points[j*2] - points[2]) +
1087 SQ(from->grid->squares[i].points[j*2+1] - points[3]));
1088 if (dist < 0.1)
1089 dkey[match++] = j;
1090 }
1091
1092 if (match == 2) {
1093 dest = i;
1094 break;
1095 }
1096 }
1097
1098 return dest;
1099 }
1100
interpret_move(const game_state * state,game_ui * ui,const game_drawstate * ds,int x,int y,int button)1101 static char *interpret_move(const game_state *state, game_ui *ui,
1102 const game_drawstate *ds,
1103 int x, int y, int button)
1104 {
1105 int direction, mask, i;
1106 int skey[2], dkey[2];
1107
1108 button = button & (~MOD_MASK | MOD_NUM_KEYPAD);
1109
1110 /*
1111 * Moves can be made with the cursor keys or numeric keypad, or
1112 * alternatively you can left-click and the polyhedron will
1113 * move in the general direction of the mouse pointer.
1114 */
1115 if (button == CURSOR_UP || button == (MOD_NUM_KEYPAD | '8'))
1116 direction = UP;
1117 else if (button == CURSOR_DOWN || button == (MOD_NUM_KEYPAD | '2'))
1118 direction = DOWN;
1119 else if (button == CURSOR_LEFT || button == (MOD_NUM_KEYPAD | '4'))
1120 direction = LEFT;
1121 else if (button == CURSOR_RIGHT || button == (MOD_NUM_KEYPAD | '6'))
1122 direction = RIGHT;
1123 else if (button == (MOD_NUM_KEYPAD | '7'))
1124 direction = UP_LEFT;
1125 else if (button == (MOD_NUM_KEYPAD | '1'))
1126 direction = DOWN_LEFT;
1127 else if (button == (MOD_NUM_KEYPAD | '9'))
1128 direction = UP_RIGHT;
1129 else if (button == (MOD_NUM_KEYPAD | '3'))
1130 direction = DOWN_RIGHT;
1131 else if (button == LEFT_BUTTON) {
1132 /*
1133 * Find the bearing of the click point from the current
1134 * square's centre.
1135 */
1136 int cx, cy;
1137 double angle;
1138
1139 cx = (int)(state->grid->squares[state->current].x * GRID_SCALE) + ds->ox;
1140 cy = (int)(state->grid->squares[state->current].y * GRID_SCALE) + ds->oy;
1141
1142 if (x == cx && y == cy)
1143 return NULL; /* clicked in exact centre! */
1144 angle = atan2(y - cy, x - cx);
1145
1146 /*
1147 * There are three possibilities.
1148 *
1149 * - This square is a square, so we choose between UP,
1150 * DOWN, LEFT and RIGHT by dividing the available angle
1151 * at the 45-degree points.
1152 *
1153 * - This square is an up-pointing triangle, so we choose
1154 * between DOWN, LEFT and RIGHT by dividing into
1155 * 120-degree arcs.
1156 *
1157 * - This square is a down-pointing triangle, so we choose
1158 * between UP, LEFT and RIGHT in the inverse manner.
1159 *
1160 * Don't forget that since our y-coordinates increase
1161 * downwards, `angle' is measured _clockwise_ from the
1162 * x-axis, not anticlockwise as most mathematicians would
1163 * instinctively assume.
1164 */
1165 if (state->grid->squares[state->current].npoints == 4) {
1166 /* Square. */
1167 if (fabs(angle) > 3*PI/4)
1168 direction = LEFT;
1169 else if (fabs(angle) < PI/4)
1170 direction = RIGHT;
1171 else if (angle > 0)
1172 direction = DOWN;
1173 else
1174 direction = UP;
1175 } else if (state->grid->squares[state->current].directions[UP] == 0) {
1176 /* Up-pointing triangle. */
1177 if (angle < -PI/2 || angle > 5*PI/6)
1178 direction = LEFT;
1179 else if (angle > PI/6)
1180 direction = DOWN;
1181 else
1182 direction = RIGHT;
1183 } else {
1184 /* Down-pointing triangle. */
1185 assert(state->grid->squares[state->current].directions[DOWN] == 0);
1186 if (angle > PI/2 || angle < -5*PI/6)
1187 direction = LEFT;
1188 else if (angle < -PI/6)
1189 direction = UP;
1190 else
1191 direction = RIGHT;
1192 }
1193 } else
1194 return NULL;
1195
1196 mask = state->grid->squares[state->current].directions[direction];
1197 if (mask == 0)
1198 return NULL;
1199
1200 /*
1201 * Translate diagonal directions into orthogonal ones.
1202 */
1203 if (direction > DOWN) {
1204 for (i = LEFT; i <= DOWN; i++)
1205 if (state->grid->squares[state->current].directions[i] == mask) {
1206 direction = i;
1207 break;
1208 }
1209 assert(direction <= DOWN);
1210 }
1211
1212 if (find_move_dest(state, direction, skey, dkey) < 0)
1213 return NULL;
1214
1215 if (direction == LEFT) return dupstr("L");
1216 if (direction == RIGHT) return dupstr("R");
1217 if (direction == UP) return dupstr("U");
1218 if (direction == DOWN) return dupstr("D");
1219
1220 return NULL; /* should never happen */
1221 }
1222
execute_move(const game_state * from,const char * move)1223 static game_state *execute_move(const game_state *from, const char *move)
1224 {
1225 game_state *ret;
1226 float angle;
1227 struct solid *poly;
1228 int pkey[2];
1229 int skey[2], dkey[2];
1230 int i, j, dest;
1231 int direction;
1232
1233 switch (*move) {
1234 case 'L': direction = LEFT; break;
1235 case 'R': direction = RIGHT; break;
1236 case 'U': direction = UP; break;
1237 case 'D': direction = DOWN; break;
1238 default: return NULL;
1239 }
1240
1241 dest = find_move_dest(from, direction, skey, dkey);
1242 if (dest < 0)
1243 return NULL;
1244
1245 ret = dup_game(from);
1246 ret->current = dest;
1247
1248 /*
1249 * So we know what grid square we're aiming for, and we also
1250 * know the two key points (as indices in both the source and
1251 * destination grid squares) which are invariant between source
1252 * and destination.
1253 *
1254 * Next we must roll the polyhedron on to that square. So we
1255 * find the indices of the key points within the polyhedron's
1256 * vertex array, then use those in a call to transform_poly,
1257 * and align the result on the new grid square.
1258 */
1259 {
1260 int all_pkey[4];
1261 align_poly(from->solid, &from->grid->squares[from->current], all_pkey);
1262 pkey[0] = all_pkey[skey[0]];
1263 pkey[1] = all_pkey[skey[1]];
1264 /*
1265 * Now pkey[0] corresponds to skey[0] and dkey[0], and
1266 * likewise [1].
1267 */
1268 }
1269
1270 /*
1271 * Now find the angle through which to rotate the polyhedron.
1272 * Do this by finding the two faces that share the two vertices
1273 * we've found, and taking the dot product of their normals.
1274 */
1275 {
1276 int f[2], nf = 0;
1277 float dp;
1278
1279 for (i = 0; i < from->solid->nfaces; i++) {
1280 int match = 0;
1281 for (j = 0; j < from->solid->order; j++)
1282 if (from->solid->faces[i*from->solid->order + j] == pkey[0] ||
1283 from->solid->faces[i*from->solid->order + j] == pkey[1])
1284 match++;
1285 if (match == 2) {
1286 assert(nf < 2);
1287 f[nf++] = i;
1288 }
1289 }
1290
1291 assert(nf == 2);
1292
1293 dp = 0;
1294 for (i = 0; i < 3; i++)
1295 dp += (from->solid->normals[f[0]*3+i] *
1296 from->solid->normals[f[1]*3+i]);
1297 angle = (float)acos(dp);
1298 }
1299
1300 /*
1301 * Now transform the polyhedron. We aren't entirely sure
1302 * whether we need to rotate through angle or -angle, and the
1303 * simplest way round this is to try both and see which one
1304 * aligns successfully!
1305 *
1306 * Unfortunately, _both_ will align successfully if this is a
1307 * cube, which won't tell us anything much. So for that
1308 * particular case, I resort to gross hackery: I simply negate
1309 * the angle before trying the alignment, depending on the
1310 * direction. Which directions work which way is determined by
1311 * pure trial and error. I said it was gross :-/
1312 */
1313 {
1314 int all_pkey[4];
1315 bool success;
1316
1317 if (from->solid->order == 4 && direction == UP)
1318 angle = -angle; /* HACK */
1319
1320 poly = transform_poly(from->solid,
1321 from->grid->squares[from->current].flip,
1322 pkey[0], pkey[1], angle);
1323 flip_poly(poly, from->grid->squares[ret->current].flip);
1324 success = align_poly(poly, &from->grid->squares[ret->current], all_pkey);
1325
1326 if (!success) {
1327 sfree(poly);
1328 angle = -angle;
1329 poly = transform_poly(from->solid,
1330 from->grid->squares[from->current].flip,
1331 pkey[0], pkey[1], angle);
1332 flip_poly(poly, from->grid->squares[ret->current].flip);
1333 success = align_poly(poly, &from->grid->squares[ret->current], all_pkey);
1334 }
1335
1336 assert(success);
1337 }
1338
1339 /*
1340 * Now we have our rotated polyhedron, which we expect to be
1341 * exactly congruent to the one we started with - but with the
1342 * faces permuted. So we map that congruence and thereby figure
1343 * out how to permute the faces as a result of the polyhedron
1344 * having rolled.
1345 */
1346 {
1347 int *newcolours = snewn(from->solid->nfaces, int);
1348
1349 for (i = 0; i < from->solid->nfaces; i++)
1350 newcolours[i] = -1;
1351
1352 for (i = 0; i < from->solid->nfaces; i++) {
1353 int nmatch = 0;
1354
1355 /*
1356 * Now go through the transformed polyhedron's faces
1357 * and figure out which one's normal is approximately
1358 * equal to this one.
1359 */
1360 for (j = 0; j < poly->nfaces; j++) {
1361 float dist;
1362 int k;
1363
1364 dist = 0;
1365
1366 for (k = 0; k < 3; k++)
1367 dist += SQ(poly->normals[j*3+k] -
1368 from->solid->normals[i*3+k]);
1369
1370 if (APPROXEQ(dist, 0)) {
1371 nmatch++;
1372 newcolours[i] = ret->facecolours[j];
1373 }
1374 }
1375
1376 assert(nmatch == 1);
1377 }
1378
1379 for (i = 0; i < from->solid->nfaces; i++)
1380 assert(newcolours[i] != -1);
1381
1382 sfree(ret->facecolours);
1383 ret->facecolours = newcolours;
1384 }
1385
1386 ret->movecount++;
1387
1388 /*
1389 * And finally, swap the colour between the bottom face of the
1390 * polyhedron and the face we've just landed on.
1391 *
1392 * We don't do this if the game is already complete, since we
1393 * allow the user to roll the fully blue polyhedron around the
1394 * grid as a feeble reward.
1395 */
1396 if (!ret->completed) {
1397 i = lowest_face(from->solid);
1398 j = ret->facecolours[i];
1399 ret->facecolours[i] = GET_SQUARE(ret, ret->current);
1400 SET_SQUARE(ret, ret->current, j);
1401
1402 /*
1403 * Detect game completion.
1404 */
1405 j = 0;
1406 for (i = 0; i < ret->solid->nfaces; i++)
1407 if (ret->facecolours[i])
1408 j++;
1409 if (j == ret->solid->nfaces)
1410 ret->completed = ret->movecount;
1411 }
1412
1413 sfree(poly);
1414
1415 /*
1416 * Align the normal polyhedron with its grid square, to get key
1417 * points for non-animated display.
1418 */
1419 {
1420 int pkey[4];
1421 bool success;
1422
1423 success = align_poly(ret->solid, &ret->grid->squares[ret->current], pkey);
1424 assert(success);
1425
1426 ret->dpkey[0] = pkey[0];
1427 ret->dpkey[1] = pkey[1];
1428 ret->dgkey[0] = 0;
1429 ret->dgkey[1] = 1;
1430 }
1431
1432
1433 ret->spkey[0] = pkey[0];
1434 ret->spkey[1] = pkey[1];
1435 ret->sgkey[0] = skey[0];
1436 ret->sgkey[1] = skey[1];
1437 ret->previous = from->current;
1438 ret->angle = angle;
1439
1440 return ret;
1441 }
1442
1443 /* ----------------------------------------------------------------------
1444 * Drawing routines.
1445 */
1446
1447 struct bbox {
1448 float l, r, u, d;
1449 };
1450
find_bbox_callback(void * ctx,struct grid_square * sq)1451 static void find_bbox_callback(void *ctx, struct grid_square *sq)
1452 {
1453 struct bbox *bb = (struct bbox *)ctx;
1454 int i;
1455
1456 for (i = 0; i < sq->npoints; i++) {
1457 if (bb->l > sq->points[i*2]) bb->l = sq->points[i*2];
1458 if (bb->r < sq->points[i*2]) bb->r = sq->points[i*2];
1459 if (bb->u > sq->points[i*2+1]) bb->u = sq->points[i*2+1];
1460 if (bb->d < sq->points[i*2+1]) bb->d = sq->points[i*2+1];
1461 }
1462 }
1463
find_bbox(const game_params * params)1464 static struct bbox find_bbox(const game_params *params)
1465 {
1466 struct bbox bb;
1467
1468 /*
1469 * These should be hugely more than the real bounding box will
1470 * be.
1471 */
1472 bb.l = 2.0F * (params->d1 + params->d2);
1473 bb.r = -2.0F * (params->d1 + params->d2);
1474 bb.u = 2.0F * (params->d1 + params->d2);
1475 bb.d = -2.0F * (params->d1 + params->d2);
1476 enum_grid_squares(params, find_bbox_callback, &bb);
1477
1478 return bb;
1479 }
1480
1481 #define XSIZE(gs, bb, solid) \
1482 ((int)(((bb).r - (bb).l + 2*(solid)->border) * gs))
1483 #define YSIZE(gs, bb, solid) \
1484 ((int)(((bb).d - (bb).u + 2*(solid)->border) * gs))
1485
game_compute_size(const game_params * params,int tilesize,int * x,int * y)1486 static void game_compute_size(const game_params *params, int tilesize,
1487 int *x, int *y)
1488 {
1489 struct bbox bb = find_bbox(params);
1490
1491 *x = XSIZE(tilesize, bb, solids[params->solid]);
1492 *y = YSIZE(tilesize, bb, solids[params->solid]);
1493 }
1494
game_set_size(drawing * dr,game_drawstate * ds,const game_params * params,int tilesize)1495 static void game_set_size(drawing *dr, game_drawstate *ds,
1496 const game_params *params, int tilesize)
1497 {
1498 struct bbox bb = find_bbox(params);
1499
1500 ds->gridscale = (float)tilesize;
1501 ds->ox = (int)(-(bb.l - solids[params->solid]->border) * ds->gridscale);
1502 ds->oy = (int)(-(bb.u - solids[params->solid]->border) * ds->gridscale);
1503 }
1504
game_colours(frontend * fe,int * ncolours)1505 static float *game_colours(frontend *fe, int *ncolours)
1506 {
1507 float *ret = snewn(3 * NCOLOURS, float);
1508
1509 frontend_default_colour(fe, &ret[COL_BACKGROUND * 3]);
1510
1511 ret[COL_BORDER * 3 + 0] = 0.0;
1512 ret[COL_BORDER * 3 + 1] = 0.0;
1513 ret[COL_BORDER * 3 + 2] = 0.0;
1514
1515 ret[COL_BLUE * 3 + 0] = 0.0;
1516 ret[COL_BLUE * 3 + 1] = 0.0;
1517 ret[COL_BLUE * 3 + 2] = 1.0;
1518
1519 *ncolours = NCOLOURS;
1520 return ret;
1521 }
1522
game_new_drawstate(drawing * dr,const game_state * state)1523 static game_drawstate *game_new_drawstate(drawing *dr, const game_state *state)
1524 {
1525 struct game_drawstate *ds = snew(struct game_drawstate);
1526
1527 ds->ox = ds->oy = 0;
1528 ds->gridscale = 0.0F; /* not decided yet */
1529
1530 return ds;
1531 }
1532
game_free_drawstate(drawing * dr,game_drawstate * ds)1533 static void game_free_drawstate(drawing *dr, game_drawstate *ds)
1534 {
1535 sfree(ds);
1536 }
1537
game_get_cursor_location(const game_ui * ui,const game_drawstate * ds,const game_state * state,const game_params * params,int * x,int * y,int * w,int * h)1538 static void game_get_cursor_location(const game_ui *ui,
1539 const game_drawstate *ds,
1540 const game_state *state,
1541 const game_params *params,
1542 int *x, int *y, int *w, int *h)
1543 {
1544 struct bbox bb;
1545
1546 bb.l = 2.0F * (params->d1 + params->d2);
1547 bb.r = -2.0F * (params->d1 + params->d2);
1548 bb.u = 2.0F * (params->d1 + params->d2);
1549 bb.d = -2.0F * (params->d1 + params->d2);
1550
1551 find_bbox_callback(&bb, state->grid->squares + state->current);
1552
1553 *x = ((int)(bb.l * GRID_SCALE) + ds->ox);
1554 *y = ((int)(bb.u * GRID_SCALE) + ds->oy);
1555 *w = (bb.r - bb.l) * GRID_SCALE;
1556 *h = (bb.d - bb.u) * GRID_SCALE;
1557 }
1558
game_redraw(drawing * dr,game_drawstate * ds,const game_state * oldstate,const game_state * state,int dir,const game_ui * ui,float animtime,float flashtime)1559 static void game_redraw(drawing *dr, game_drawstate *ds,
1560 const game_state *oldstate, const game_state *state,
1561 int dir, const game_ui *ui,
1562 float animtime, float flashtime)
1563 {
1564 int i, j;
1565 struct bbox bb = find_bbox(&state->params);
1566 struct solid *poly;
1567 const int *pkey, *gkey;
1568 float t[3];
1569 float angle;
1570 int square;
1571
1572 draw_rect(dr, 0, 0, XSIZE(GRID_SCALE, bb, state->solid),
1573 YSIZE(GRID_SCALE, bb, state->solid), COL_BACKGROUND);
1574
1575 if (dir < 0) {
1576 const game_state *t;
1577
1578 /*
1579 * This is an Undo. So reverse the order of the states, and
1580 * run the roll timer backwards.
1581 */
1582 assert(oldstate);
1583
1584 t = oldstate;
1585 oldstate = state;
1586 state = t;
1587
1588 animtime = ROLLTIME - animtime;
1589 }
1590
1591 if (!oldstate) {
1592 oldstate = state;
1593 angle = 0.0;
1594 square = state->current;
1595 pkey = state->dpkey;
1596 gkey = state->dgkey;
1597 } else {
1598 angle = state->angle * animtime / ROLLTIME;
1599 square = state->previous;
1600 pkey = state->spkey;
1601 gkey = state->sgkey;
1602 }
1603 state = oldstate;
1604
1605 for (i = 0; i < state->grid->nsquares; i++) {
1606 int coords[8];
1607
1608 for (j = 0; j < state->grid->squares[i].npoints; j++) {
1609 coords[2*j] = ((int)(state->grid->squares[i].points[2*j] * GRID_SCALE)
1610 + ds->ox);
1611 coords[2*j+1] = ((int)(state->grid->squares[i].points[2*j+1]*GRID_SCALE)
1612 + ds->oy);
1613 }
1614
1615 draw_polygon(dr, coords, state->grid->squares[i].npoints,
1616 GET_SQUARE(state, i) ? COL_BLUE : COL_BACKGROUND,
1617 COL_BORDER);
1618 }
1619
1620 /*
1621 * Now compute and draw the polyhedron.
1622 */
1623 poly = transform_poly(state->solid, state->grid->squares[square].flip,
1624 pkey[0], pkey[1], angle);
1625
1626 /*
1627 * Compute the translation required to align the two key points
1628 * on the polyhedron with the same key points on the current
1629 * face.
1630 */
1631 for (i = 0; i < 3; i++) {
1632 float tc = 0.0;
1633
1634 for (j = 0; j < 2; j++) {
1635 float grid_coord;
1636
1637 if (i < 2) {
1638 grid_coord =
1639 state->grid->squares[square].points[gkey[j]*2+i];
1640 } else {
1641 grid_coord = 0.0;
1642 }
1643
1644 tc += (grid_coord - poly->vertices[pkey[j]*3+i]);
1645 }
1646
1647 t[i] = tc / 2;
1648 }
1649 for (i = 0; i < poly->nvertices; i++)
1650 for (j = 0; j < 3; j++)
1651 poly->vertices[i*3+j] += t[j];
1652
1653 /*
1654 * Now actually draw each face.
1655 */
1656 for (i = 0; i < poly->nfaces; i++) {
1657 float points[8];
1658 int coords[8];
1659
1660 for (j = 0; j < poly->order; j++) {
1661 int f = poly->faces[i*poly->order + j];
1662 points[j*2] = (poly->vertices[f*3+0] -
1663 poly->vertices[f*3+2] * poly->shear);
1664 points[j*2+1] = (poly->vertices[f*3+1] -
1665 poly->vertices[f*3+2] * poly->shear);
1666 }
1667
1668 for (j = 0; j < poly->order; j++) {
1669 coords[j*2] = (int)floor(points[j*2] * GRID_SCALE) + ds->ox;
1670 coords[j*2+1] = (int)floor(points[j*2+1] * GRID_SCALE) + ds->oy;
1671 }
1672
1673 /*
1674 * Find out whether these points are in a clockwise or
1675 * anticlockwise arrangement. If the latter, discard the
1676 * face because it's facing away from the viewer.
1677 *
1678 * This would involve fiddly winding-number stuff for a
1679 * general polygon, but for the simple parallelograms we'll
1680 * be seeing here, all we have to do is check whether the
1681 * corners turn right or left. So we'll take the vector
1682 * from point 0 to point 1, turn it right 90 degrees,
1683 * and check the sign of the dot product with that and the
1684 * next vector (point 1 to point 2).
1685 */
1686 {
1687 float v1x = points[2]-points[0];
1688 float v1y = points[3]-points[1];
1689 float v2x = points[4]-points[2];
1690 float v2y = points[5]-points[3];
1691 float dp = v1x * v2y - v1y * v2x;
1692
1693 if (dp <= 0)
1694 continue;
1695 }
1696
1697 draw_polygon(dr, coords, poly->order,
1698 state->facecolours[i] ? COL_BLUE : COL_BACKGROUND,
1699 COL_BORDER);
1700 }
1701 sfree(poly);
1702
1703 draw_update(dr, 0, 0, XSIZE(GRID_SCALE, bb, state->solid),
1704 YSIZE(GRID_SCALE, bb, state->solid));
1705
1706 /*
1707 * Update the status bar.
1708 */
1709 {
1710 char statusbuf[256];
1711
1712 sprintf(statusbuf, "%sMoves: %d",
1713 (state->completed ? "COMPLETED! " : ""),
1714 (state->completed ? state->completed : state->movecount));
1715
1716 status_bar(dr, statusbuf);
1717 }
1718 }
1719
game_anim_length(const game_state * oldstate,const game_state * newstate,int dir,game_ui * ui)1720 static float game_anim_length(const game_state *oldstate,
1721 const game_state *newstate, int dir, game_ui *ui)
1722 {
1723 return ROLLTIME;
1724 }
1725
game_flash_length(const game_state * oldstate,const game_state * newstate,int dir,game_ui * ui)1726 static float game_flash_length(const game_state *oldstate,
1727 const game_state *newstate, int dir, game_ui *ui)
1728 {
1729 return 0.0F;
1730 }
1731
game_status(const game_state * state)1732 static int game_status(const game_state *state)
1733 {
1734 return state->completed ? +1 : 0;
1735 }
1736
game_timing_state(const game_state * state,game_ui * ui)1737 static bool game_timing_state(const game_state *state, game_ui *ui)
1738 {
1739 return true;
1740 }
1741
game_print_size(const game_params * params,float * x,float * y)1742 static void game_print_size(const game_params *params, float *x, float *y)
1743 {
1744 }
1745
game_print(drawing * dr,const game_state * state,int tilesize)1746 static void game_print(drawing *dr, const game_state *state, int tilesize)
1747 {
1748 }
1749
1750 #ifdef COMBINED
1751 #define thegame cube
1752 #endif
1753
1754 const struct game thegame = {
1755 "Cube", "games.cube", "cube",
1756 default_params,
1757 game_fetch_preset, NULL,
1758 decode_params,
1759 encode_params,
1760 free_params,
1761 dup_params,
1762 true, game_configure, custom_params,
1763 validate_params,
1764 new_game_desc,
1765 validate_desc,
1766 new_game,
1767 dup_game,
1768 free_game,
1769 false, solve_game,
1770 false, game_can_format_as_text_now, game_text_format,
1771 new_ui,
1772 free_ui,
1773 encode_ui,
1774 decode_ui,
1775 NULL, /* game_request_keys */
1776 game_changed_state,
1777 interpret_move,
1778 execute_move,
1779 PREFERRED_GRID_SCALE, game_compute_size, game_set_size,
1780 game_colours,
1781 game_new_drawstate,
1782 game_free_drawstate,
1783 game_redraw,
1784 game_anim_length,
1785 game_flash_length,
1786 game_get_cursor_location,
1787 game_status,
1788 false, false, game_print_size, game_print,
1789 true, /* wants_statusbar */
1790 false, game_timing_state,
1791 0, /* flags */
1792 };
1793