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clientobject: add null checks
[waspsaliva.git] / src / mapgen / dungeongen.cpp
blobacdb1a0f0f27edd0348f5cf8b72d6f2f4563e4de
1 /*
2 Minetest
3 Copyright (C) 2010-2018 celeron55, Perttu Ahola <celeron55@gmail.com>
4 Copyright (C) 2015-2018 paramat
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU Lesser General Public License as published by
8 the Free Software Foundation; either version 2.1 of the License, or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public License along
17 with this program; if not, write to the Free Software Foundation, Inc.,
18 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
19 */
20
21 #include "dungeongen.h"
22 #include <cmath>
23 #include "mapgen.h"
24 #include "voxel.h"
25 #include "noise.h"
26 #include "mapblock.h"
27 #include "mapnode.h"
28 #include "map.h"
29 #include "nodedef.h"
30 #include "settings.h"
31
32 //#define DGEN_USE_TORCHES
33
34
35 ///////////////////////////////////////////////////////////////////////////////
36
37
38 DungeonGen::DungeonGen(const NodeDefManager *ndef,
39 GenerateNotifier *gennotify, DungeonParams *dparams)
40 {
41 assert(ndef);
42
43 this->ndef = ndef;
44 this->gennotify = gennotify;
45
46 #ifdef DGEN_USE_TORCHES
47 c_torch = ndef->getId("default:torch");
48 #endif
49
50 if (dparams) {
51 dp = *dparams;
52 } else {
53 // Default dungeon parameters
54 dp.seed = 0;
55
56 dp.c_wall = ndef->getId("mapgen_cobble");
57 dp.c_alt_wall = ndef->getId("mapgen_mossycobble");
58 dp.c_stair = ndef->getId("mapgen_stair_cobble");
59
60 dp.diagonal_dirs = false;
61 dp.only_in_ground = true;
62 dp.holesize = v3s16(1, 2, 1);
63 dp.corridor_len_min = 1;
64 dp.corridor_len_max = 13;
65 dp.room_size_min = v3s16(4, 4, 4);
66 dp.room_size_max = v3s16(8, 6, 8);
67 dp.room_size_large_min = v3s16(8, 8, 8);
68 dp.room_size_large_max = v3s16(16, 16, 16);
69 dp.large_room_chance = 1;
70 dp.num_rooms = 8;
71 dp.num_dungeons = 1;
72 dp.notifytype = GENNOTIFY_DUNGEON;
73
74 dp.np_alt_wall =
75 NoiseParams(-0.4, 1.0, v3f(40.0, 40.0, 40.0), 32474, 6, 1.1, 2.0);
76 }
77 }
78
79
80 void DungeonGen::generate(MMVManip *vm, u32 bseed, v3s16 nmin, v3s16 nmax)
81 {
82 if (dp.num_dungeons == 0)
83 return;
84
85 assert(vm);
86
87 //TimeTaker t("gen dungeons");
88
89 this->vm = vm;
90 this->blockseed = bseed;
91 random.seed(bseed + 2);
92
93 // Dungeon generator doesn't modify places which have this set
94 vm->clearFlag(VMANIP_FLAG_DUNGEON_INSIDE | VMANIP_FLAG_DUNGEON_PRESERVE);
95
96 if (dp.only_in_ground) {
97 // Set all air and liquid drawtypes to be untouchable to make dungeons generate
98 // in ground only.
99 // Set 'ignore' to be untouchable to prevent generation in ungenerated neighbor
100 // mapchunks, to avoid dungeon rooms generating outside ground.
101 // Like randomwalk caves, preserve nodes that have 'is_ground_content = false',
102 // to avoid dungeons that generate out beyond the edge of a mapchunk destroying
103 // nodes added by mods in 'register_on_generated()'.
104 for (s16 z = nmin.Z; z <= nmax.Z; z++) {
105 for (s16 y = nmin.Y; y <= nmax.Y; y++) {
106 u32 i = vm->m_area.index(nmin.X, y, z);
107 for (s16 x = nmin.X; x <= nmax.X; x++) {
108 content_t c = vm->m_data[i].getContent();
109 NodeDrawType dtype = ndef->get(c).drawtype;
110 if (dtype == NDT_AIRLIKE || dtype == NDT_LIQUID ||
111 c == CONTENT_IGNORE || !ndef->get(c).is_ground_content)
112 vm->m_flags[i] |= VMANIP_FLAG_DUNGEON_PRESERVE;
113 i++;
114 }
115 }
116 }
117 }
118
119 // Add them
120 for (u32 i = 0; i < dp.num_dungeons; i++)
121 makeDungeon(v3s16(1, 1, 1) * MAP_BLOCKSIZE);
122
123 // Optionally convert some structure to alternative structure
124 if (dp.c_alt_wall == CONTENT_IGNORE)
125 return;
126
127 for (s16 z = nmin.Z; z <= nmax.Z; z++)
128 for (s16 y = nmin.Y; y <= nmax.Y; y++) {
129 u32 i = vm->m_area.index(nmin.X, y, z);
130 for (s16 x = nmin.X; x <= nmax.X; x++) {
131 if (vm->m_data[i].getContent() == dp.c_wall) {
132 if (NoisePerlin3D(&dp.np_alt_wall, x, y, z, blockseed) > 0.0f)
133 vm->m_data[i].setContent(dp.c_alt_wall);
134 }
135 i++;
136 }
137 }
138
139 //printf("== gen dungeons: %dms\n", t.stop());
140 }
141
142
143 void DungeonGen::makeDungeon(v3s16 start_padding)
144 {
145 const v3s16 &areasize = vm->m_area.getExtent();
146 v3s16 roomsize;
147 v3s16 roomplace;
148
149 /*
150 Find place for first room.
151 */
152 bool fits = false;
153 for (u32 i = 0; i < 100 && !fits; i++) {
154 if (dp.large_room_chance >= 1) {
155 roomsize.Z = random.range(dp.room_size_large_min.Z, dp.room_size_large_max.Z);
156 roomsize.Y = random.range(dp.room_size_large_min.Y, dp.room_size_large_max.Y);
157 roomsize.X = random.range(dp.room_size_large_min.X, dp.room_size_large_max.X);
158 } else {
159 roomsize.Z = random.range(dp.room_size_min.Z, dp.room_size_max.Z);
160 roomsize.Y = random.range(dp.room_size_min.Y, dp.room_size_max.Y);
161 roomsize.X = random.range(dp.room_size_min.X, dp.room_size_max.X);
162 }
163
164 // start_padding is used to disallow starting the generation of
165 // a dungeon in a neighboring generation chunk
166 roomplace = vm->m_area.MinEdge + start_padding;
167 roomplace.Z += random.range(0, areasize.Z - roomsize.Z - start_padding.Z);
168 roomplace.Y += random.range(0, areasize.Y - roomsize.Y - start_padding.Y);
169 roomplace.X += random.range(0, areasize.X - roomsize.X - start_padding.X);
170
171 /*
172 Check that we're not putting the room to an unknown place,
173 otherwise it might end up floating in the air
174 */
175 fits = true;
176 for (s16 z = 0; z < roomsize.Z; z++)
177 for (s16 y = 0; y < roomsize.Y; y++)
178 for (s16 x = 0; x < roomsize.X; x++) {
179 v3s16 p = roomplace + v3s16(x, y, z);
180 u32 vi = vm->m_area.index(p);
181 if ((vm->m_flags[vi] & VMANIP_FLAG_DUNGEON_UNTOUCHABLE) ||
182 vm->m_data[vi].getContent() == CONTENT_IGNORE) {
183 fits = false;
184 break;
185 }
186 }
187 }
188 // No place found
189 if (!fits)
190 return;
191
192 /*
193 Stores the center position of the last room made, so that
194 a new corridor can be started from the last room instead of
195 the new room, if chosen so.
196 */
197 v3s16 last_room_center = roomplace + v3s16(roomsize.X / 2, 1, roomsize.Z / 2);
198
199 for (u32 i = 0; i < dp.num_rooms; i++) {
200 // Make a room to the determined place
201 makeRoom(roomsize, roomplace);
202
203 v3s16 room_center = roomplace + v3s16(roomsize.X / 2, 1, roomsize.Z / 2);
204 if (gennotify)
205 gennotify->addEvent(dp.notifytype, room_center);
206
207 #ifdef DGEN_USE_TORCHES
208 // Place torch at room center (for testing)
209 vm->m_data[vm->m_area.index(room_center)] = MapNode(c_torch);
210 #endif
211
212 // Quit if last room
213 if (i + 1 == dp.num_rooms)
214 break;
215
216 // Determine walker start position
217
218 bool start_in_last_room = (random.range(0, 2) != 0);
219
220 v3s16 walker_start_place;
221
222 if (start_in_last_room) {
223 walker_start_place = last_room_center;
224 } else {
225 walker_start_place = room_center;
226 // Store center of current room as the last one
227 last_room_center = room_center;
228 }
229
230 // Create walker and find a place for a door
231 v3s16 doorplace;
232 v3s16 doordir;
233
234 m_pos = walker_start_place;
235 if (!findPlaceForDoor(doorplace, doordir))
236 return;
237
238 if (random.range(0, 1) == 0)
239 // Make the door
240 makeDoor(doorplace, doordir);
241 else
242 // Don't actually make a door
243 doorplace -= doordir;
244
245 // Make a random corridor starting from the door
246 v3s16 corridor_end;
247 v3s16 corridor_end_dir;
248 makeCorridor(doorplace, doordir, corridor_end, corridor_end_dir);
249
250 // Find a place for a random sized room
251 if (dp.large_room_chance > 1 && random.range(1, dp.large_room_chance) == 1) {
252 // Large room
253 roomsize.Z = random.range(dp.room_size_large_min.Z, dp.room_size_large_max.Z);
254 roomsize.Y = random.range(dp.room_size_large_min.Y, dp.room_size_large_max.Y);
255 roomsize.X = random.range(dp.room_size_large_min.X, dp.room_size_large_max.X);
256 } else {
257 roomsize.Z = random.range(dp.room_size_min.Z, dp.room_size_max.Z);
258 roomsize.Y = random.range(dp.room_size_min.Y, dp.room_size_max.Y);
259 roomsize.X = random.range(dp.room_size_min.X, dp.room_size_max.X);
260 }
261
262 m_pos = corridor_end;
263 m_dir = corridor_end_dir;
264 if (!findPlaceForRoomDoor(roomsize, doorplace, doordir, roomplace))
265 return;
266
267 if (random.range(0, 1) == 0)
268 // Make the door
269 makeDoor(doorplace, doordir);
270 else
271 // Don't actually make a door
272 roomplace -= doordir;
273 }
274 }
275
276
277 void DungeonGen::makeRoom(v3s16 roomsize, v3s16 roomplace)
278 {
279 MapNode n_wall(dp.c_wall);
280 MapNode n_air(CONTENT_AIR);
281
282 // Make +-X walls
283 for (s16 z = 0; z < roomsize.Z; z++)
284 for (s16 y = 0; y < roomsize.Y; y++) {
285 {
286 v3s16 p = roomplace + v3s16(0, y, z);
287 if (!vm->m_area.contains(p))
288 continue;
289 u32 vi = vm->m_area.index(p);
290 if (vm->m_flags[vi] & VMANIP_FLAG_DUNGEON_UNTOUCHABLE)
291 continue;
292 vm->m_data[vi] = n_wall;
293 }
294 {
295 v3s16 p = roomplace + v3s16(roomsize.X - 1, y, z);
296 if (!vm->m_area.contains(p))
297 continue;
298 u32 vi = vm->m_area.index(p);
299 if (vm->m_flags[vi] & VMANIP_FLAG_DUNGEON_UNTOUCHABLE)
300 continue;
301 vm->m_data[vi] = n_wall;
302 }
303 }
304
305 // Make +-Z walls
306 for (s16 x = 0; x < roomsize.X; x++)
307 for (s16 y = 0; y < roomsize.Y; y++) {
308 {
309 v3s16 p = roomplace + v3s16(x, y, 0);
310 if (!vm->m_area.contains(p))
311 continue;
312 u32 vi = vm->m_area.index(p);
313 if (vm->m_flags[vi] & VMANIP_FLAG_DUNGEON_UNTOUCHABLE)
314 continue;
315 vm->m_data[vi] = n_wall;
316 }
317 {
318 v3s16 p = roomplace + v3s16(x, y, roomsize.Z - 1);
319 if (!vm->m_area.contains(p))
320 continue;
321 u32 vi = vm->m_area.index(p);
322 if (vm->m_flags[vi] & VMANIP_FLAG_DUNGEON_UNTOUCHABLE)
323 continue;
324 vm->m_data[vi] = n_wall;
325 }
326 }
327
328 // Make +-Y walls (floor and ceiling)
329 for (s16 z = 0; z < roomsize.Z; z++)
330 for (s16 x = 0; x < roomsize.X; x++) {
331 {
332 v3s16 p = roomplace + v3s16(x, 0, z);
333 if (!vm->m_area.contains(p))
334 continue;
335 u32 vi = vm->m_area.index(p);
336 if (vm->m_flags[vi] & VMANIP_FLAG_DUNGEON_UNTOUCHABLE)
337 continue;
338 vm->m_data[vi] = n_wall;
339 }
340 {
341 v3s16 p = roomplace + v3s16(x,roomsize. Y - 1, z);
342 if (!vm->m_area.contains(p))
343 continue;
344 u32 vi = vm->m_area.index(p);
345 if (vm->m_flags[vi] & VMANIP_FLAG_DUNGEON_UNTOUCHABLE)
346 continue;
347 vm->m_data[vi] = n_wall;
348 }
349 }
350
351 // Fill with air
352 for (s16 z = 1; z < roomsize.Z - 1; z++)
353 for (s16 y = 1; y < roomsize.Y - 1; y++)
354 for (s16 x = 1; x < roomsize.X - 1; x++) {
355 v3s16 p = roomplace + v3s16(x, y, z);
356 if (!vm->m_area.contains(p))
357 continue;
358 u32 vi = vm->m_area.index(p);
359 vm->m_flags[vi] |= VMANIP_FLAG_DUNGEON_UNTOUCHABLE;
360 vm->m_data[vi] = n_air;
361 }
362 }
363
364
365 void DungeonGen::makeFill(v3s16 place, v3s16 size,
366 u8 avoid_flags, MapNode n, u8 or_flags)
367 {
368 for (s16 z = 0; z < size.Z; z++)
369 for (s16 y = 0; y < size.Y; y++)
370 for (s16 x = 0; x < size.X; x++) {
371 v3s16 p = place + v3s16(x, y, z);
372 if (!vm->m_area.contains(p))
373 continue;
374 u32 vi = vm->m_area.index(p);
375 if (vm->m_flags[vi] & avoid_flags)
376 continue;
377 vm->m_flags[vi] |= or_flags;
378 vm->m_data[vi] = n;
379 }
380 }
381
382
383 void DungeonGen::makeHole(v3s16 place)
384 {
385 makeFill(place, dp.holesize, 0, MapNode(CONTENT_AIR),
386 VMANIP_FLAG_DUNGEON_INSIDE);
387 }
388
389
390 void DungeonGen::makeDoor(v3s16 doorplace, v3s16 doordir)
391 {
392 makeHole(doorplace);
393
394 #ifdef DGEN_USE_TORCHES
395 // Place torch (for testing)
396 vm->m_data[vm->m_area.index(doorplace)] = MapNode(c_torch);
397 #endif
398 }
399
400
401 void DungeonGen::makeCorridor(v3s16 doorplace, v3s16 doordir,
402 v3s16 &result_place, v3s16 &result_dir)
403 {
404 makeHole(doorplace);
405 v3s16 p0 = doorplace;
406 v3s16 dir = doordir;
407 u32 length = random.range(dp.corridor_len_min, dp.corridor_len_max);
408 u32 partlength = random.range(dp.corridor_len_min, dp.corridor_len_max);
409 u32 partcount = 0;
410 s16 make_stairs = 0;
411
412 if (random.next() % 2 == 0 && partlength >= 3)
413 make_stairs = random.next() % 2 ? 1 : -1;
414
415 for (u32 i = 0; i < length; i++) {
416 v3s16 p = p0 + dir;
417 if (partcount != 0)
418 p.Y += make_stairs;
419
420 // Check segment of minimum size corridor is in voxelmanip
421 if (vm->m_area.contains(p) && vm->m_area.contains(p + v3s16(0, 1, 0))) {
422 if (make_stairs) {
423 makeFill(p + v3s16(-1, -1, -1),
424 dp.holesize + v3s16(2, 3, 2),
425 VMANIP_FLAG_DUNGEON_UNTOUCHABLE,
426 MapNode(dp.c_wall),
427 0);
428 makeFill(p, dp.holesize, VMANIP_FLAG_DUNGEON_UNTOUCHABLE,
429 MapNode(CONTENT_AIR), VMANIP_FLAG_DUNGEON_INSIDE);
430 makeFill(p - dir, dp.holesize, VMANIP_FLAG_DUNGEON_UNTOUCHABLE,
431 MapNode(CONTENT_AIR), VMANIP_FLAG_DUNGEON_INSIDE);
432
433 // TODO: fix stairs code so it works 100%
434 // (quite difficult)
435
436 // exclude stairs from the bottom step
437 // exclude stairs from diagonal steps
438 if (((dir.X ^ dir.Z) & 1) &&
439 (((make_stairs == 1) && i != 0) ||
440 ((make_stairs == -1) && i != length - 1))) {
441 // rotate face 180 deg if
442 // making stairs backwards
443 int facedir = dir_to_facedir(dir * make_stairs);
444 v3s16 ps = p;
445 u16 stair_width = (dir.Z != 0) ? dp.holesize.X : dp.holesize.Z;
446 // Stair width direction vector
447 v3s16 swv = (dir.Z != 0) ? v3s16(1, 0, 0) : v3s16(0, 0, 1);
448
449 for (u16 st = 0; st < stair_width; st++) {
450 if (make_stairs == -1) {
451 u32 vi = vm->m_area.index(ps.X - dir.X, ps.Y - 1, ps.Z - dir.Z);
452 if (vm->m_area.contains(ps + v3s16(-dir.X, -1, -dir.Z)) &&
453 vm->m_data[vi].getContent() == dp.c_wall) {
454 vm->m_flags[vi] |= VMANIP_FLAG_DUNGEON_UNTOUCHABLE;
455 vm->m_data[vi] = MapNode(dp.c_stair, 0, facedir);
456 }
457 } else if (make_stairs == 1) {
458 u32 vi = vm->m_area.index(ps.X, ps.Y - 1, ps.Z);
459 if (vm->m_area.contains(ps + v3s16(0, -1, 0)) &&
460 vm->m_data[vi].getContent() == dp.c_wall) {
461 vm->m_flags[vi] |= VMANIP_FLAG_DUNGEON_UNTOUCHABLE;
462 vm->m_data[vi] = MapNode(dp.c_stair, 0, facedir);
463 }
464 }
465 ps += swv;
466 }
467 }
468 } else {
469 makeFill(p + v3s16(-1, -1, -1),
470 dp.holesize + v3s16(2, 2, 2),
471 VMANIP_FLAG_DUNGEON_UNTOUCHABLE,
472 MapNode(dp.c_wall),
473 0);
474 makeHole(p);
475 }
476
477 p0 = p;
478 } else {
479 // Can't go here, turn away
480 dir = turn_xz(dir, random.range(0, 1));
481 make_stairs = -make_stairs;
482 partcount = 0;
483 partlength = random.range(1, length);
484 continue;
485 }
486
487 partcount++;
488 if (partcount >= partlength) {
489 partcount = 0;
490
491 random_turn(random, dir);
492
493 partlength = random.range(1, length);
494
495 make_stairs = 0;
496 if (random.next() % 2 == 0 && partlength >= 3)
497 make_stairs = random.next() % 2 ? 1 : -1;
498 }
499 }
500 result_place = p0;
501 result_dir = dir;
502 }
503
504
505 bool DungeonGen::findPlaceForDoor(v3s16 &result_place, v3s16 &result_dir)
506 {
507 for (u32 i = 0; i < 100; i++) {
508 v3s16 p = m_pos + m_dir;
509 v3s16 p1 = p + v3s16(0, 1, 0);
510 if (!vm->m_area.contains(p) || !vm->m_area.contains(p1) || i % 4 == 0) {
511 randomizeDir();
512 continue;
513 }
514 if (vm->getNodeNoExNoEmerge(p).getContent() == dp.c_wall &&
515 vm->getNodeNoExNoEmerge(p1).getContent() == dp.c_wall) {
516 // Found wall, this is a good place!
517 result_place = p;
518 result_dir = m_dir;
519 // Randomize next direction
520 randomizeDir();
521 return true;
522 }
523 /*
524 Determine where to move next
525 */
526 // Jump one up if the actual space is there
527 if (vm->getNodeNoExNoEmerge(p +
528 v3s16(0, 0, 0)).getContent() == dp.c_wall &&
529 vm->getNodeNoExNoEmerge(p +
530 v3s16(0, 1, 0)).getContent() == CONTENT_AIR &&
531 vm->getNodeNoExNoEmerge(p +
532 v3s16(0, 2, 0)).getContent() == CONTENT_AIR)
533 p += v3s16(0,1,0);
534 // Jump one down if the actual space is there
535 if (vm->getNodeNoExNoEmerge(p +
536 v3s16(0, 1, 0)).getContent() == dp.c_wall &&
537 vm->getNodeNoExNoEmerge(p +
538 v3s16(0, 0, 0)).getContent() == CONTENT_AIR &&
539 vm->getNodeNoExNoEmerge(p +
540 v3s16(0, -1, 0)).getContent() == CONTENT_AIR)
541 p += v3s16(0, -1, 0);
542 // Check if walking is now possible
543 if (vm->getNodeNoExNoEmerge(p).getContent() != CONTENT_AIR ||
544 vm->getNodeNoExNoEmerge(p +
545 v3s16(0, 1, 0)).getContent() != CONTENT_AIR) {
546 // Cannot continue walking here
547 randomizeDir();
548 continue;
549 }
550 // Move there
551 m_pos = p;
552 }
553 return false;
554 }
555
556
557 bool DungeonGen::findPlaceForRoomDoor(v3s16 roomsize, v3s16 &result_doorplace,
558 v3s16 &result_doordir, v3s16 &result_roomplace)
559 {
560 for (s16 trycount = 0; trycount < 30; trycount++) {
561 v3s16 doorplace;
562 v3s16 doordir;
563 bool r = findPlaceForDoor(doorplace, doordir);
564 if (!r)
565 continue;
566 v3s16 roomplace;
567 // X east, Z north, Y up
568 if (doordir == v3s16(1, 0, 0)) // X+
569 roomplace = doorplace +
570 v3s16(0, -1, random.range(-roomsize.Z + 2, -2));
571 if (doordir == v3s16(-1, 0, 0)) // X-
572 roomplace = doorplace +
573 v3s16(-roomsize.X + 1, -1, random.range(-roomsize.Z + 2, -2));
574 if (doordir == v3s16(0, 0, 1)) // Z+
575 roomplace = doorplace +
576 v3s16(random.range(-roomsize.X + 2, -2), -1, 0);
577 if (doordir == v3s16(0, 0, -1)) // Z-
578 roomplace = doorplace +
579 v3s16(random.range(-roomsize.X + 2, -2), -1, -roomsize.Z + 1);
580
581 // Check fit
582 bool fits = true;
583 for (s16 z = 1; z < roomsize.Z - 1; z++)
584 for (s16 y = 1; y < roomsize.Y - 1; y++)
585 for (s16 x = 1; x < roomsize.X - 1; x++) {
586 v3s16 p = roomplace + v3s16(x, y, z);
587 if (!vm->m_area.contains(p)) {
588 fits = false;
589 break;
590 }
591 if (vm->m_flags[vm->m_area.index(p)] & VMANIP_FLAG_DUNGEON_INSIDE) {
592 fits = false;
593 break;
594 }
595 }
596 if (!fits) {
597 // Find new place
598 continue;
599 }
600 result_doorplace = doorplace;
601 result_doordir = doordir;
602 result_roomplace = roomplace;
603 return true;
604 }
605 return false;
606 }
607
608
609 v3s16 rand_ortho_dir(PseudoRandom &random, bool diagonal_dirs)
610 {
611 // Make diagonal directions somewhat rare
612 if (diagonal_dirs && (random.next() % 4 == 0)) {
613 v3s16 dir;
614 int trycount = 0;
615
616 do {
617 trycount++;
618
619 dir.Z = random.next() % 3 - 1;
620 dir.Y = 0;
621 dir.X = random.next() % 3 - 1;
622 } while ((dir.X == 0 || dir.Z == 0) && trycount < 10);
623
624 return dir;
625 }
626
627 if (random.next() % 2 == 0)
628 return random.next() % 2 ? v3s16(-1, 0, 0) : v3s16(1, 0, 0);
629
630 return random.next() % 2 ? v3s16(0, 0, -1) : v3s16(0, 0, 1);
631 }
632
633
634 v3s16 turn_xz(v3s16 olddir, int t)
635 {
636 v3s16 dir;
637 if (t == 0) {
638 // Turn right
639 dir.X = olddir.Z;
640 dir.Z = -olddir.X;
641 dir.Y = olddir.Y;
642 } else {
643 // Turn left
644 dir.X = -olddir.Z;
645 dir.Z = olddir.X;
646 dir.Y = olddir.Y;
647 }
648 return dir;
649 }
650
651
652 void random_turn(PseudoRandom &random, v3s16 &dir)
653 {
654 int turn = random.range(0, 2);
655 if (turn == 0) {
656 // Go straight: nothing to do
657 return;
658 } else if (turn == 1) {
659 // Turn right
660 dir = turn_xz(dir, 0);
661 } else {
662 // Turn left
663 dir = turn_xz(dir, 1);
664 }
665 }
666
667
668 int dir_to_facedir(v3s16 d)
669 {
670 if (abs(d.X) > abs(d.Z))
671 return d.X < 0 ? 3 : 1;
672
673 return d.Z < 0 ? 2 : 0;
674 }
minetest hacked client (dragonfire fork)