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1 /*
2 Minetest
3 Copyright (C) 2010-2015 kwolekr, Ryan Kwolek <kwolekr@minetest.net>
4 Copyright (C) 2010-2015 paramat, Matt Gregory
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
22 #include "mapgen.h"
23 #include "voxel.h"
24 #include "noise.h"
25 #include "mapblock.h"
26 #include "mapnode.h"
27 #include "map.h"
28 #include "content_sao.h"
29 #include "nodedef.h"
30 #include "voxelalgorithms.h"
31 //#include "profiler.h" // For TimeTaker
32 #include "settings.h" // For g_settings
33 #include "emerge.h"
34 #include "dungeongen.h"
35 #include "cavegen.h"
36 #include "treegen.h"
37 #include "mg_biome.h"
38 #include "mg_ore.h"
39 #include "mg_decoration.h"
40 #include "mapgen_v5.h"
41 #include "util/directiontables.h"
42
43
44 FlagDesc flagdesc_mapgen_v5[] = {
45         {NULL,         0}
46 };
47
48
49 MapgenV5::MapgenV5(int mapgenid, MapgenParams *params, EmergeManager *emerge)
50         : Mapgen(mapgenid, params, emerge)
51 {
52         this->m_emerge = emerge;
53         this->bmgr     = emerge->biomemgr;
54
55         // amount of elements to skip for the next index
56         // for noise/height/biome maps (not vmanip)
57         this->ystride = csize.X;
58         this->zstride = csize.X * (csize.Y + 2);
59
60         this->biomemap  = new u8[csize.X * csize.Z];
61         this->heightmap = new s16[csize.X * csize.Z];
62         this->heatmap   = NULL;
63         this->humidmap  = NULL;
64
65         MapgenV5Params *sp = (MapgenV5Params *)params->sparams;
66         this->spflags      = sp->spflags;
67
68         // Terrain noise
69         noise_filler_depth = new Noise(&sp->np_filler_depth, seed, csize.X, csize.Z);
70         noise_factor       = new Noise(&sp->np_factor,       seed, csize.X, csize.Z);
71         noise_height       = new Noise(&sp->np_height,       seed, csize.X, csize.Z);
72
73         // 3D terrain noise
74         noise_cave1  = new Noise(&sp->np_cave1,  seed, csize.X, csize.Y + 2, csize.Z);
75         noise_cave2  = new Noise(&sp->np_cave2,  seed, csize.X, csize.Y + 2, csize.Z);
76         noise_ground = new Noise(&sp->np_ground, seed, csize.X, csize.Y + 2, csize.Z);
77
78         // Biome noise
79         noise_heat           = new Noise(&params->np_biome_heat,           seed, csize.X, csize.Z);
80         noise_humidity       = new Noise(&params->np_biome_humidity,       seed, csize.X, csize.Z);
81         noise_heat_blend     = new Noise(&params->np_biome_heat_blend,     seed, csize.X, csize.Z);
82         noise_humidity_blend = new Noise(&params->np_biome_humidity_blend, seed, csize.X, csize.Z);
83
84         //// Resolve nodes to be used
85         INodeDefManager *ndef = emerge->ndef;
86
87         c_stone                = ndef->getId("mapgen_stone");
88         c_water_source         = ndef->getId("mapgen_water_source");
89         c_lava_source          = ndef->getId("mapgen_lava_source");
90         c_desert_stone         = ndef->getId("mapgen_desert_stone");
91         c_ice                  = ndef->getId("mapgen_ice");
92         c_sandstone            = ndef->getId("mapgen_sandstone");
93
94         c_cobble               = ndef->getId("mapgen_cobble");
95         c_stair_cobble         = ndef->getId("mapgen_stair_cobble");
96         c_mossycobble          = ndef->getId("mapgen_mossycobble");
97         c_sandstonebrick       = ndef->getId("mapgen_sandstonebrick");
98         c_stair_sandstonebrick = ndef->getId("mapgen_stair_sandstonebrick");
99
100         if (c_ice == CONTENT_IGNORE)
101                 c_ice = CONTENT_AIR;
102         if (c_mossycobble == CONTENT_IGNORE)
103                 c_mossycobble = c_cobble;
104         if (c_stair_cobble == CONTENT_IGNORE)
105                 c_stair_cobble = c_cobble;
106         if (c_sandstonebrick == CONTENT_IGNORE)
107                 c_sandstonebrick = c_sandstone;
108         if (c_stair_sandstonebrick == CONTENT_IGNORE)
109                 c_stair_sandstonebrick = c_sandstone;
110 }
111
112
113 MapgenV5::~MapgenV5()
114 {
115         delete noise_filler_depth;
116         delete noise_factor;
117         delete noise_height;
118         delete noise_cave1;
119         delete noise_cave2;
120         delete noise_ground;
121
122         delete noise_heat;
123         delete noise_humidity;
124         delete noise_heat_blend;
125         delete noise_humidity_blend;
126
127         delete[] heightmap;
128         delete[] biomemap;
129 }
130
131
132 MapgenV5Params::MapgenV5Params()
133 {
134         spflags = 0;
135
136         np_filler_depth = NoiseParams(0, 1,  v3f(150, 150, 150), 261,    4, 0.7,  2.0);
137         np_factor       = NoiseParams(0, 1,  v3f(250, 250, 250), 920381, 3, 0.45, 2.0);
138         np_height       = NoiseParams(0, 10, v3f(250, 250, 250), 84174,  4, 0.5,  2.0);
139         np_cave1        = NoiseParams(0, 12, v3f(50,  50,  50),  52534,  4, 0.5,  2.0);
140         np_cave2        = NoiseParams(0, 12, v3f(50,  50,  50),  10325,  4, 0.5,  2.0);
141         np_ground       = NoiseParams(0, 40, v3f(80,  80,  80),  983240, 4, 0.55, 2.0, NOISE_FLAG_EASED);
142 }
143
144
145 //#define CAVE_NOISE_SCALE 12.0
146 //#define CAVE_NOISE_THRESHOLD (1.5/CAVE_NOISE_SCALE) = 0.125
147
148
149 void MapgenV5Params::readParams(const Settings *settings)
150 {
151         settings->getFlagStrNoEx("mgv5_spflags", spflags, flagdesc_mapgen_v5);
152
153         settings->getNoiseParams("mgv5_np_filler_depth", np_filler_depth);
154         settings->getNoiseParams("mgv5_np_factor",       np_factor);
155         settings->getNoiseParams("mgv5_np_height",       np_height);
156         settings->getNoiseParams("mgv5_np_cave1",        np_cave1);
157         settings->getNoiseParams("mgv5_np_cave2",        np_cave2);
158         settings->getNoiseParams("mgv5_np_ground",       np_ground);
159 }
160
161
162 void MapgenV5Params::writeParams(Settings *settings) const
163 {
164         settings->setFlagStr("mgv5_spflags", spflags, flagdesc_mapgen_v5, U32_MAX);
165
166         settings->setNoiseParams("mgv5_np_filler_depth", np_filler_depth);
167         settings->setNoiseParams("mgv5_np_factor",       np_factor);
168         settings->setNoiseParams("mgv5_np_height",       np_height);
169         settings->setNoiseParams("mgv5_np_cave1",        np_cave1);
170         settings->setNoiseParams("mgv5_np_cave2",        np_cave2);
171         settings->setNoiseParams("mgv5_np_ground",       np_ground);
172 }
173
174
175 int MapgenV5::getGroundLevelAtPoint(v2s16 p)
176 {
177         //TimeTaker t("getGroundLevelAtPoint", NULL, PRECISION_MICRO);
178
179         float f = 0.55 + NoisePerlin2D(&noise_factor->np, p.X, p.Y, seed);
180         if (f < 0.01)
181                 f = 0.01;
182         else if (f >= 1.0)
183                 f *= 1.6;
184         float h = NoisePerlin2D(&noise_height->np, p.X, p.Y, seed);
185
186         s16 search_start = 128; // Only bother searching this range, actual
187         s16 search_end = -128;  // ground level is rarely higher or lower.
188
189         for (s16 y = search_start; y >= search_end; y--) {
190                 float n_ground = NoisePerlin3D(&noise_ground->np, p.X, y, p.Y, seed);
191                 // If solid
192                 if (n_ground * f > y - h) {
193                         // If either top 2 nodes of search are solid this is inside a
194                         // mountain or floatland with no space for the player to spawn.
195                         if (y >= search_start - 1)
196                                 return MAX_MAP_GENERATION_LIMIT;
197                         else
198                                 return y; // Ground below at least 2 nodes of space
199                 }
200         }
201
202         //printf("getGroundLevelAtPoint: %dus\n", t.stop());
203         return -MAX_MAP_GENERATION_LIMIT;
204 }
205
206
207 void MapgenV5::makeChunk(BlockMakeData *data)
208 {
209         // Pre-conditions
210         assert(data->vmanip);
211         assert(data->nodedef);
212         assert(data->blockpos_requested.X >= data->blockpos_min.X &&
213                 data->blockpos_requested.Y >= data->blockpos_min.Y &&
214                 data->blockpos_requested.Z >= data->blockpos_min.Z);
215         assert(data->blockpos_requested.X <= data->blockpos_max.X &&
216                 data->blockpos_requested.Y <= data->blockpos_max.Y &&
217                 data->blockpos_requested.Z <= data->blockpos_max.Z);
218
219         generating = true;
220         vm   = data->vmanip;
221         ndef = data->nodedef;
222         //TimeTaker t("makeChunk");
223
224         v3s16 blockpos_min = data->blockpos_min;
225         v3s16 blockpos_max = data->blockpos_max;
226         node_min = blockpos_min * MAP_BLOCKSIZE;
227         node_max = (blockpos_max + v3s16(1, 1, 1)) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
228         full_node_min = (blockpos_min - 1) * MAP_BLOCKSIZE;
229         full_node_max = (blockpos_max + 2) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
230
231         // Create a block-specific seed
232         blockseed = getBlockSeed2(full_node_min, seed);
233
234         // Make some noise
235         calculateNoise();
236
237         // Generate base terrain
238         s16 stone_surface_max_y = generateBaseTerrain();
239
240         // Create heightmap
241         updateHeightmap(node_min, node_max);
242
243         // Create biomemap at heightmap surface
244         bmgr->calcBiomes(csize.X, csize.Z, noise_heat->result,
245                 noise_humidity->result, heightmap, biomemap);
246
247         // Actually place the biome-specific nodes
248         MgStoneType stone_type = generateBiomes(noise_heat->result, noise_humidity->result);
249
250         // Generate caves
251         if ((flags & MG_CAVES) && (stone_surface_max_y >= node_min.Y))
252                 generateCaves(stone_surface_max_y);
253
254         // Generate dungeons and desert temples
255         if ((flags & MG_DUNGEONS) && (stone_surface_max_y >= node_min.Y)) {
256                 DungeonParams dp;
257
258                 dp.np_rarity  = nparams_dungeon_rarity;
259                 dp.np_density = nparams_dungeon_density;
260                 dp.np_wetness = nparams_dungeon_wetness;
261                 dp.c_water    = c_water_source;
262                 if (stone_type == STONE) {
263                         dp.c_cobble = c_cobble;
264                         dp.c_moss   = c_mossycobble;
265                         dp.c_stair  = c_stair_cobble;
266
267                         dp.diagonal_dirs = false;
268                         dp.mossratio     = 3.0;
269                         dp.holesize      = v3s16(1, 2, 1);
270                         dp.roomsize      = v3s16(0, 0, 0);
271                         dp.notifytype    = GENNOTIFY_DUNGEON;
272                 } else if (stone_type == DESERT_STONE) {
273                         dp.c_cobble = c_desert_stone;
274                         dp.c_moss   = c_desert_stone;
275                         dp.c_stair  = c_desert_stone;
276
277                         dp.diagonal_dirs = true;
278                         dp.mossratio     = 0.0;
279                         dp.holesize      = v3s16(2, 3, 2);
280                         dp.roomsize      = v3s16(2, 5, 2);
281                         dp.notifytype    = GENNOTIFY_TEMPLE;
282                 } else if (stone_type == SANDSTONE) {
283                         dp.c_cobble = c_sandstonebrick;
284                         dp.c_moss   = c_sandstonebrick;
285                         dp.c_stair  = c_sandstonebrick;
286
287                         dp.diagonal_dirs = false;
288                         dp.mossratio     = 0.0;
289                         dp.holesize      = v3s16(2, 2, 2);
290                         dp.roomsize      = v3s16(2, 0, 2);
291                         dp.notifytype    = GENNOTIFY_DUNGEON;
292                 }
293
294                 DungeonGen dgen(this, &dp);
295                 dgen.generate(blockseed, full_node_min, full_node_max);
296         }
297
298         // Generate the registered decorations
299         if (flags & MG_DECORATIONS)
300                 m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
301
302         // Generate the registered ores
303         m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max);
304
305         // Sprinkle some dust on top after everything else was generated
306         dustTopNodes();
307
308         //printf("makeChunk: %dms\n", t.stop());
309
310         // Add top and bottom side of water to transforming_liquid queue
311         updateLiquid(&data->transforming_liquid, full_node_min, full_node_max);
312
313         // Calculate lighting
314         if (flags & MG_LIGHT) {
315                 calcLighting(node_min - v3s16(0, 1, 0), node_max + v3s16(0, 1, 0),
316                         full_node_min, full_node_max);
317         }
318
319         this->generating = false;
320 }
321
322
323 void MapgenV5::calculateNoise()
324 {
325         //TimeTaker t("calculateNoise", NULL, PRECISION_MICRO);
326         int x = node_min.X;
327         int y = node_min.Y - 1;
328         int z = node_min.Z;
329
330         noise_factor->perlinMap2D(x, z);
331         noise_height->perlinMap2D(x, z);
332         noise_ground->perlinMap3D(x, y, z);
333
334         if (flags & MG_CAVES) {
335                 noise_cave1->perlinMap3D(x, y, z);
336                 noise_cave2->perlinMap3D(x, y, z);
337         }
338
339         noise_filler_depth->perlinMap2D(x, z);
340         noise_heat->perlinMap2D(x, z);
341         noise_humidity->perlinMap2D(x, z);
342         noise_heat_blend->perlinMap2D(x, z);
343         noise_humidity_blend->perlinMap2D(x, z);
344
345         for (s32 i = 0; i < csize.X * csize.Z; i++) {
346                 noise_heat->result[i] += noise_heat_blend->result[i];
347                 noise_humidity->result[i] += noise_humidity_blend->result[i];
348         }
349
350         heatmap = noise_heat->result;
351         humidmap = noise_humidity->result;
352         //printf("calculateNoise: %dus\n", t.stop());
353 }
354
355
356 //bool is_cave(u32 index) {
357 //      double d1 = contour(noise_cave1->result[index]);
358 //      double d2 = contour(noise_cave2->result[index]);
359 //      return d1*d2 > CAVE_NOISE_THRESHOLD;
360 //}
361
362 //bool val_is_ground(v3s16 p, u32 index, u32 index2d) {
363 //      double f = 0.55 + noise_factor->result[index2d];
364 //      if(f < 0.01)
365 //              f = 0.01;
366 //      else if(f >= 1.0)
367 //              f *= 1.6;
368 //      double h = WATER_LEVEL + 10 * noise_height->result[index2d];
369 //      return (noise_ground->result[index] * f > (double)p.Y - h);
370 //}
371
372
373 int MapgenV5::generateBaseTerrain()
374 {
375         u32 index = 0;
376         u32 index2d = 0;
377         int stone_surface_max_y = -MAX_MAP_GENERATION_LIMIT;
378
379         for (s16 z=node_min.Z; z<=node_max.Z; z++) {
380                 for (s16 y=node_min.Y - 1; y<=node_max.Y + 1; y++) {
381                         u32 i = vm->m_area.index(node_min.X, y, z);
382                         for (s16 x=node_min.X; x<=node_max.X; x++, i++, index++, index2d++) {
383                                 if (vm->m_data[i].getContent() != CONTENT_IGNORE)
384                                         continue;
385
386                                 float f = 0.55 + noise_factor->result[index2d];
387                                 if (f < 0.01)
388                                         f = 0.01;
389                                 else if (f >= 1.0)
390                                         f *= 1.6;
391                                 float h = noise_height->result[index2d];
392
393                                 if (noise_ground->result[index] * f < y - h) {
394                                         if (y <= water_level)
395                                                 vm->m_data[i] = MapNode(c_water_source);
396                                         else
397                                                 vm->m_data[i] = MapNode(CONTENT_AIR);
398                                 } else {
399                                         vm->m_data[i] = MapNode(c_stone);
400                                         if (y > stone_surface_max_y)
401                                                 stone_surface_max_y = y;
402                                 }
403                         }
404                         index2d -= ystride;
405                 }
406                 index2d += ystride;
407         }
408
409         return stone_surface_max_y;
410 }
411
412
413 MgStoneType MapgenV5::generateBiomes(float *heat_map, float *humidity_map)
414 {
415         v3s16 em = vm->m_area.getExtent();
416         u32 index = 0;
417         MgStoneType stone_type = STONE;
418
419         for (s16 z = node_min.Z; z <= node_max.Z; z++)
420         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
421                 Biome *biome = NULL;
422                 u16 depth_top = 0;
423                 u16 base_filler = 0;
424                 u16 depth_water_top = 0;
425                 u32 vi = vm->m_area.index(x, node_max.Y, z);
426
427                 // Check node at base of mapchunk above, either a node of a previously
428                 // generated mapchunk or if not, a node of overgenerated base terrain.
429                 content_t c_above = vm->m_data[vi + em.X].getContent();
430                 bool air_above = c_above == CONTENT_AIR;
431                 bool water_above = c_above == c_water_source;
432
433                 // If there is air or water above enable top/filler placement, otherwise force
434                 // nplaced to stone level by setting a number exceeding any possible filler depth.
435                 u16 nplaced = (air_above || water_above) ? 0 : U16_MAX;
436
437                 for (s16 y = node_max.Y; y >= node_min.Y; y--) {
438                         content_t c = vm->m_data[vi].getContent();
439
440                         // Biome is recalculated each time an upper surface is detected while
441                         // working down a column. The selected biome then remains in effect for
442                         // all nodes below until the next surface and biome recalculation.
443                         // Biome is recalculated:
444                         // 1. At the surface of stone below air or water.
445                         // 2. At the surface of water below air.
446                         // 3. When stone or water is detected but biome has not yet been calculated.
447                         if ((c == c_stone && (air_above || water_above || !biome)) ||
448                                         (c == c_water_source && (air_above || !biome))) {
449                                 biome = bmgr->getBiome(heat_map[index], humidity_map[index], y);
450                                 depth_top = biome->depth_top;
451                                 base_filler = MYMAX(depth_top + biome->depth_filler
452                                                 + noise_filler_depth->result[index], 0);
453                                 depth_water_top = biome->depth_water_top;
454
455                                 // Detect stone type for dungeons during every biome calculation.
456                                 // This is more efficient than detecting per-node and will not
457                                 // miss any desert stone or sandstone biomes.
458                                 if (biome->c_stone == c_desert_stone)
459                                         stone_type = DESERT_STONE;
460                                 else if (biome->c_stone == c_sandstone)
461                                         stone_type = SANDSTONE;
462                         }
463
464                         if (c == c_stone) {
465                                 content_t c_below = vm->m_data[vi - em.X].getContent();
466
467                                 // If the node below isn't solid, make this node stone, so that
468                                 // any top/filler nodes above are structurally supported.
469                                 // This is done by aborting the cycle of top/filler placement
470                                 // immediately by forcing nplaced to stone level.
471                                 if (c_below == CONTENT_AIR || c_below == c_water_source)
472                                         nplaced = U16_MAX;
473
474                                 if (nplaced < depth_top) {
475                                         vm->m_data[vi] = MapNode(biome->c_top);
476                                         nplaced++;
477                                 } else if (nplaced < base_filler) {
478                                         vm->m_data[vi] = MapNode(biome->c_filler);
479                                         nplaced++;
480                                 } else {
481                                         vm->m_data[vi] = MapNode(biome->c_stone);
482                                 }
483
484                                 air_above = false;
485                                 water_above = false;
486                         } else if (c == c_water_source) {
487                                 vm->m_data[vi] = MapNode((y > (s32)(water_level - depth_water_top)) ?
488                                                 biome->c_water_top : biome->c_water);
489                                 nplaced = 0;  // Enable top/filler placement for next surface
490                                 air_above = false;
491                                 water_above = true;
492                         } else if (c == CONTENT_AIR) {
493                                 nplaced = 0;  // Enable top/filler placement for next surface
494                                 air_above = true;
495                                 water_above = false;
496                         } else {  // Possible various nodes overgenerated from neighbouring mapchunks
497                                 nplaced = U16_MAX;  // Disable top/filler placement
498                                 air_above = false;
499                                 water_above = false;
500                         }
501
502                         vm->m_area.add_y(em, vi, -1);
503                 }
504         }
505
506         return stone_type;
507 }
508
509
510 void MapgenV5::generateCaves(int max_stone_y)
511 {
512         if (max_stone_y >= node_min.Y) {
513                 u32 index = 0;
514
515                 for (s16 z = node_min.Z; z <= node_max.Z; z++)
516                 for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
517                         u32 i = vm->m_area.index(node_min.X, y, z);
518                         for (s16 x = node_min.X; x <= node_max.X; x++, i++, index++) {
519                                 float d1 = contour(noise_cave1->result[index]);
520                                 float d2 = contour(noise_cave2->result[index]);
521                                 if (d1 * d2 > 0.125f) {
522                                         content_t c = vm->m_data[i].getContent();
523                                         if (!ndef->get(c).is_ground_content || c == CONTENT_AIR)
524                                                 continue;
525
526                                         vm->m_data[i] = MapNode(CONTENT_AIR);
527                                 }
528                         }
529                 }
530         }
531
532         if (node_max.Y > MGV5_LARGE_CAVE_DEPTH)
533                 return;
534
535         PseudoRandom ps(blockseed + 21343);
536         u32 bruises_count = ps.range(0, 2);
537         for (u32 i = 0; i < bruises_count; i++) {
538                 CaveV5 cave(this, &ps);
539                 cave.makeCave(node_min, node_max, max_stone_y);
540         }
541 }
542
543
544 void MapgenV5::dustTopNodes()
545 {
546         if (node_max.Y < water_level)
547                 return;
548
549         v3s16 em = vm->m_area.getExtent();
550         u32 index = 0;
551
552         for (s16 z = node_min.Z; z <= node_max.Z; z++)
553         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
554                 Biome *biome = (Biome *)bmgr->getRaw(biomemap[index]);
555
556                 if (biome->c_dust == CONTENT_IGNORE)
557                         continue;
558
559                 u32 vi = vm->m_area.index(x, full_node_max.Y, z);
560                 content_t c_full_max = vm->m_data[vi].getContent();
561                 s16 y_start;
562
563                 if (c_full_max == CONTENT_AIR) {
564                         y_start = full_node_max.Y - 1;
565                 } else if (c_full_max == CONTENT_IGNORE) {
566                         vi = vm->m_area.index(x, node_max.Y + 1, z);
567                         content_t c_max = vm->m_data[vi].getContent();
568
569                         if (c_max == CONTENT_AIR)
570                                 y_start = node_max.Y;
571                         else
572                                 continue;
573                 } else {
574                         continue;
575                 }
576
577                 vi = vm->m_area.index(x, y_start, z);
578                 for (s16 y = y_start; y >= node_min.Y - 1; y--) {
579                         if (vm->m_data[vi].getContent() != CONTENT_AIR)
580                                 break;
581
582                         vm->m_area.add_y(em, vi, -1);
583                 }
584
585                 content_t c = vm->m_data[vi].getContent();
586                 if (!ndef->get(c).buildable_to && c != CONTENT_IGNORE && c != biome->c_dust) {
587                         vm->m_area.add_y(em, vi, 1);
588                         vm->m_data[vi] = MapNode(biome->c_dust);
589                 }
590         }
591 }