src/mapgen_fractal.cpp

   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_fractal.h"
  41
  42
  43 FlagDesc flagdesc_mapgen_fractal[] = {
  44         {NULL,    0}
  45 };
  46
  47 ///////////////////////////////////////////////////////////////////////////////////////
  48
  49
  50 MapgenFractal::MapgenFractal(int mapgenid, MapgenParams *params, EmergeManager *emerge)
  51         : Mapgen(mapgenid, params, emerge)
  52 {
  53         this->m_emerge = emerge;
  54         this->bmgr     = emerge->biomemgr;
  55
  56         //// amount of elements to skip for the next index
  57         //// for noise/height/biome maps (not vmanip)
  58         this->ystride = csize.X;
  59         this->zstride = csize.X * (csize.Y + 2);
  60
  61         this->biomemap  = new u8[csize.X * csize.Z];
  62         this->heightmap = new s16[csize.X * csize.Z];
  63         this->heatmap   = NULL;
  64         this->humidmap  = NULL;
  65
  66         MapgenFractalParams *sp = (MapgenFractalParams *)params->sparams;
  67         this->spflags = sp->spflags;
  68
  69         this->formula    = sp->formula;
  70         this->iterations = sp->iterations;
  71         this->scale      = sp->scale;
  72         this->offset     = sp->offset;
  73         this->slice_w    = sp->slice_w;
  74
  75         this->julia_x = sp->julia_x;
  76         this->julia_y = sp->julia_y;
  77         this->julia_z = sp->julia_z;
  78         this->julia_w = sp->julia_w;
  79
  80         //// 2D terrain noise
  81         noise_seabed       = new Noise(&sp->np_seabed, seed, csize.X, csize.Z);
  82         noise_filler_depth = new Noise(&sp->np_filler_depth, seed, csize.X, csize.Z);
  83
  84         //// 3D terrain noise
  85         noise_cave1 = new Noise(&sp->np_cave1, seed, csize.X, csize.Y + 2, csize.Z);
  86         noise_cave2 = new Noise(&sp->np_cave2, seed, csize.X, csize.Y + 2, csize.Z);
  87
  88         //// Biome noise
  89         noise_heat           = new Noise(&params->np_biome_heat,           seed, csize.X, csize.Z);
  90         noise_humidity       = new Noise(&params->np_biome_humidity,       seed, csize.X, csize.Z);
  91         noise_heat_blend     = new Noise(&params->np_biome_heat_blend,     seed, csize.X, csize.Z);
  92         noise_humidity_blend = new Noise(&params->np_biome_humidity_blend, seed, csize.X, csize.Z);
  93
  94         //// Resolve nodes to be used
  95         INodeDefManager *ndef = emerge->ndef;
  96
  97         c_stone                = ndef->getId("mapgen_stone");
  98         c_water_source         = ndef->getId("mapgen_water_source");
  99         c_lava_source          = ndef->getId("mapgen_lava_source");
 100         c_desert_stone         = ndef->getId("mapgen_desert_stone");
 101         c_ice                  = ndef->getId("mapgen_ice");
 102         c_sandstone            = ndef->getId("mapgen_sandstone");
 103
 104         c_cobble               = ndef->getId("mapgen_cobble");
 105         c_stair_cobble         = ndef->getId("mapgen_stair_cobble");
 106         c_mossycobble          = ndef->getId("mapgen_mossycobble");
 107         c_sandstonebrick       = ndef->getId("mapgen_sandstonebrick");
 108         c_stair_sandstonebrick = ndef->getId("mapgen_stair_sandstonebrick");
 109
 110         if (c_ice == CONTENT_IGNORE)
 111                 c_ice = CONTENT_AIR;
 112         if (c_mossycobble == CONTENT_IGNORE)
 113                 c_mossycobble = c_cobble;
 114         if (c_stair_cobble == CONTENT_IGNORE)
 115                 c_stair_cobble = c_cobble;
 116         if (c_sandstonebrick == CONTENT_IGNORE)
 117                 c_sandstonebrick = c_sandstone;
 118         if (c_stair_sandstonebrick == CONTENT_IGNORE)
 119                 c_stair_sandstonebrick = c_sandstone;
 120 }
 121
 122
 123 MapgenFractal::~MapgenFractal()
 124 {
 125         delete noise_seabed;
 126         delete noise_filler_depth;
 127         delete noise_cave1;
 128         delete noise_cave2;
 129
 130         delete noise_heat;
 131         delete noise_humidity;
 132         delete noise_heat_blend;
 133         delete noise_humidity_blend;
 134
 135         delete[] heightmap;
 136         delete[] biomemap;
 137 }
 138
 139
 140 MapgenFractalParams::MapgenFractalParams()
 141 {
 142         spflags = 0;
 143
 144         formula = 1;
 145         iterations = 11;
 146         scale = v3f(4096.0, 1024.0, 4096.0);
 147         offset = v3f(1.79, 0.0, 0.0);
 148         slice_w = 0.0;
 149
 150         julia_x = 0.33;
 151         julia_y = 0.33;
 152         julia_z = 0.33;
 153         julia_w = 0.33;
 154
 155         np_seabed       = NoiseParams(-14, 9,   v3f(600, 600, 600), 41900, 5, 0.6, 2.0);
 156         np_filler_depth = NoiseParams(0,   1.2, v3f(150, 150, 150), 261,   3, 0.7, 2.0);
 157         np_cave1        = NoiseParams(0,   12,  v3f(128, 128, 128), 52534, 4, 0.5, 2.0);
 158         np_cave2        = NoiseParams(0,   12,  v3f(128, 128, 128), 10325, 4, 0.5, 2.0);
 159 }
 160
 161
 162 void MapgenFractalParams::readParams(const Settings *settings)
 163 {
 164         settings->getFlagStrNoEx("mgfractal_spflags", spflags, flagdesc_mapgen_fractal);
 165
 166         settings->getU16NoEx("mgfractal_formula", formula);
 167         settings->getU16NoEx("mgfractal_iterations", iterations);
 168         settings->getV3FNoEx("mgfractal_scale", scale);
 169         settings->getV3FNoEx("mgfractal_offset", offset);
 170         settings->getFloatNoEx("mgfractal_slice_w", slice_w);
 171
 172         settings->getFloatNoEx("mgfractal_julia_x", julia_x);
 173         settings->getFloatNoEx("mgfractal_julia_y", julia_y);
 174         settings->getFloatNoEx("mgfractal_julia_z", julia_z);
 175         settings->getFloatNoEx("mgfractal_julia_w", julia_w);
 176
 177         settings->getNoiseParams("mgfractal_np_seabed", np_seabed);
 178         settings->getNoiseParams("mgfractal_np_filler_depth", np_filler_depth);
 179         settings->getNoiseParams("mgfractal_np_cave1", np_cave1);
 180         settings->getNoiseParams("mgfractal_np_cave2", np_cave2);
 181 }
 182
 183
 184 void MapgenFractalParams::writeParams(Settings *settings) const
 185 {
 186         settings->setFlagStr("mgfractal_spflags", spflags, flagdesc_mapgen_fractal, U32_MAX);
 187
 188         settings->setU16("mgfractal_formula", formula);
 189         settings->setU16("mgfractal_iterations", iterations);
 190         settings->setV3F("mgfractal_scale", scale);
 191         settings->setV3F("mgfractal_offset", offset);
 192         settings->setFloat("mgfractal_slice_w", slice_w);
 193
 194         settings->setFloat("mgfractal_julia_x", julia_x);
 195         settings->setFloat("mgfractal_julia_y", julia_y);
 196         settings->setFloat("mgfractal_julia_z", julia_z);
 197         settings->setFloat("mgfractal_julia_w", julia_w);
 198
 199         settings->setNoiseParams("mgfractal_np_seabed", np_seabed);
 200         settings->setNoiseParams("mgfractal_np_filler_depth", np_filler_depth);
 201         settings->setNoiseParams("mgfractal_np_cave1", np_cave1);
 202         settings->setNoiseParams("mgfractal_np_cave2", np_cave2);
 203 }
 204
 205
 206 /////////////////////////////////////////////////////////////////
 207
 208
 209 int MapgenFractal::getGroundLevelAtPoint(v2s16 p)
 210 {
 211         s16 search_start = 128;
 212         s16 search_end = -128;
 213
 214         for (s16 y = search_start; y >= search_end; y--) {
 215                 if (getFractalAtPoint(p.X, y, p.Y))
 216                         return y;
 217         }
 218
 219         return -MAX_MAP_GENERATION_LIMIT;
 220 }
 221
 222
 223 void MapgenFractal::makeChunk(BlockMakeData *data)
 224 {
 225         // Pre-conditions
 226         assert(data->vmanip);
 227         assert(data->nodedef);
 228         assert(data->blockpos_requested.X >= data->blockpos_min.X &&
 229                 data->blockpos_requested.Y >= data->blockpos_min.Y &&
 230                 data->blockpos_requested.Z >= data->blockpos_min.Z);
 231         assert(data->blockpos_requested.X <= data->blockpos_max.X &&
 232                 data->blockpos_requested.Y <= data->blockpos_max.Y &&
 233                 data->blockpos_requested.Z <= data->blockpos_max.Z);
 234
 235         this->generating = true;
 236         this->vm   = data->vmanip;
 237         this->ndef = data->nodedef;
 238         //TimeTaker t("makeChunk");
 239
 240         v3s16 blockpos_min = data->blockpos_min;
 241         v3s16 blockpos_max = data->blockpos_max;
 242         node_min = blockpos_min * MAP_BLOCKSIZE;
 243         node_max = (blockpos_max + v3s16(1, 1, 1)) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
 244         full_node_min = (blockpos_min - 1) * MAP_BLOCKSIZE;
 245         full_node_max = (blockpos_max + 2) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
 246
 247         blockseed = getBlockSeed2(full_node_min, seed);
 248
 249         // Make some noise
 250         calculateNoise();
 251
 252         // Generate base terrain, mountains, and ridges with initial heightmaps
 253         s16 stone_surface_max_y = generateTerrain();
 254
 255         // Create heightmap
 256         updateHeightmap(node_min, node_max);
 257
 258         // Create biomemap at heightmap surface
 259         bmgr->calcBiomes(csize.X, csize.Z, noise_heat->result,
 260                 noise_humidity->result, heightmap, biomemap);
 261
 262         // Actually place the biome-specific nodes
 263         MgStoneType stone_type = generateBiomes(noise_heat->result, noise_humidity->result);
 264
 265         if (flags & MG_CAVES)
 266                 generateCaves(stone_surface_max_y);
 267
 268         if ((flags & MG_DUNGEONS) && (stone_surface_max_y >= node_min.Y)) {
 269                 DungeonParams dp;
 270
 271                 dp.np_rarity  = nparams_dungeon_rarity;
 272                 dp.np_density = nparams_dungeon_density;
 273                 dp.np_wetness = nparams_dungeon_wetness;
 274                 dp.c_water    = c_water_source;
 275                 if (stone_type == STONE) {
 276                         dp.c_cobble = c_cobble;
 277                         dp.c_moss   = c_mossycobble;
 278                         dp.c_stair  = c_stair_cobble;
 279
 280                         dp.diagonal_dirs = false;
 281                         dp.mossratio     = 3.0;
 282                         dp.holesize      = v3s16(1, 2, 1);
 283                         dp.roomsize      = v3s16(0, 0, 0);
 284                         dp.notifytype    = GENNOTIFY_DUNGEON;
 285                 } else if (stone_type == DESERT_STONE) {
 286                         dp.c_cobble = c_desert_stone;
 287                         dp.c_moss   = c_desert_stone;
 288                         dp.c_stair  = c_desert_stone;
 289
 290                         dp.diagonal_dirs = true;
 291                         dp.mossratio     = 0.0;
 292                         dp.holesize      = v3s16(2, 3, 2);
 293                         dp.roomsize      = v3s16(2, 5, 2);
 294                         dp.notifytype    = GENNOTIFY_TEMPLE;
 295                 } else if (stone_type == SANDSTONE) {
 296                         dp.c_cobble = c_sandstonebrick;
 297                         dp.c_moss   = c_sandstonebrick;
 298                         dp.c_stair  = c_sandstonebrick;
 299
 300                         dp.diagonal_dirs = false;
 301                         dp.mossratio     = 0.0;
 302                         dp.holesize      = v3s16(2, 2, 2);
 303                         dp.roomsize      = v3s16(2, 0, 2);
 304                         dp.notifytype    = GENNOTIFY_DUNGEON;
 305                 }
 306
 307                 DungeonGen dgen(this, &dp);
 308                 dgen.generate(blockseed, full_node_min, full_node_max);
 309         }
 310
 311         // Generate the registered decorations
 312         if (flags & MG_DECORATIONS)
 313                 m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
 314
 315         // Generate the registered ores
 316         m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max);
 317
 318         // Sprinkle some dust on top after everything else was generated
 319         dustTopNodes();
 320
 321         //printf("makeChunk: %dms\n", t.stop());
 322
 323         updateLiquid(&data->transforming_liquid, full_node_min, full_node_max);
 324
 325         if (flags & MG_LIGHT)
 326                 calcLighting(node_min - v3s16(0, 1, 0), node_max + v3s16(0, 1, 0),
 327                         full_node_min, full_node_max);
 328
 329         //setLighting(node_min - v3s16(1, 0, 1) * MAP_BLOCKSIZE,
 330         //                      node_max + v3s16(1, 0, 1) * MAP_BLOCKSIZE, 0xFF);
 331
 332         this->generating = false;
 333 }
 334
 335
 336 void MapgenFractal::calculateNoise()
 337 {
 338         //TimeTaker t("calculateNoise", NULL, PRECISION_MICRO);
 339         int x = node_min.X;
 340         int y = node_min.Y - 1;
 341         int z = node_min.Z;
 342
 343         noise_seabed->perlinMap2D(x, z);
 344         noise_filler_depth->perlinMap2D(x, z);
 345
 346         if (flags & MG_CAVES) {
 347                 noise_cave1->perlinMap3D(x, y, z);
 348                 noise_cave2->perlinMap3D(x, y, z);
 349         }
 350
 351         noise_heat->perlinMap2D(x, z);
 352         noise_humidity->perlinMap2D(x, z);
 353         noise_heat_blend->perlinMap2D(x, z);
 354         noise_humidity_blend->perlinMap2D(x, z);
 355
 356         for (s32 i = 0; i < csize.X * csize.Z; i++) {
 357                 noise_heat->result[i] += noise_heat_blend->result[i];
 358                 noise_humidity->result[i] += noise_humidity_blend->result[i];
 359         }
 360
 361         heatmap = noise_heat->result;
 362         humidmap = noise_humidity->result;
 363         //printf("calculateNoise: %dus\n", t.stop());
 364 }
 365
 366
 367 bool MapgenFractal::getFractalAtPoint(s16 x, s16 y, s16 z)
 368 {
 369         float cx, cy, cz, cw, ox, oy, oz, ow;
 370
 371         if (formula % 2 == 0) {  // Julia sets, formula = 2, 4, 6, 8
 372                 cx = julia_x;
 373                 cy = julia_y;
 374                 cz = julia_z;
 375                 cw = julia_w;
 376                 ox = (float)x / scale.X - offset.X;
 377                 oy = (float)y / scale.Y - offset.Y;
 378                 oz = (float)z / scale.Z - offset.Z;
 379                 ow = slice_w;
 380         } else {  // Mandelbrot sets, formula = 1, 3, 5, 7
 381                 cx = (float)x / scale.X - offset.X;
 382                 cy = (float)y / scale.Y - offset.Y;
 383                 cz = (float)z / scale.Z - offset.Z;
 384                 cw = slice_w;
 385                 ox = 0.0f;
 386                 oy = 0.0f;
 387                 oz = 0.0f;
 388                 ow = 0.0f;
 389         }
 390
 391         for (u16 iter = 0; iter < iterations; iter++) {
 392                 float nx = 0.0f;
 393                 float ny = 0.0f;
 394                 float nz = 0.0f;
 395                 float nw = 0.0f;
 396
 397                 if (formula == 1 || formula == 2) {  // 4D "Roundy" Mandelbrot/Julia Set
 398                         nx = ox * ox - oy * oy - oz * oz - ow * ow + cx;
 399                         ny = 2.0f * (ox * oy + oz * ow) + cy;
 400                         nz = 2.0f * (ox * oz + oy * ow) + cz;
 401                         nw = 2.0f * (ox * ow + oy * oz) + cw;
 402                 } else if (formula == 3 || formula == 4) {  // 4D "Squarry" Mandelbrot/Julia Set
 403                         nx = ox * ox - oy * oy - oz * oz - ow * ow + cx;
 404                         ny = 2.0f * (ox * oy + oz * ow) + cy;
 405                         nz = 2.0f * (ox * oz + oy * ow) + cz;
 406                         nw = 2.0f * (ox * ow - oy * oz) + cw;
 407                 } else if (formula == 5 || formula == 6) {  // 4D "Mandy Cousin" Mandelbrot/Julia Set
 408                         nx = ox * ox - oy * oy - oz * oz + ow * ow + cx;
 409                         ny = 2.0f * (ox * oy + oz * ow) + cy;
 410                         nz = 2.0f * (ox * oz + oy * ow) + cz;
 411                         nw = 2.0f * (ox * ow + oy * oz) + cw;
 412                 } else if (formula == 7 || formula == 8) {  // 4D "Variation" Mandelbrot/Julia Set
 413                         nx = ox * ox - oy * oy - oz * oz - ow * ow + cx;
 414                         ny = 2.0f * (ox * oy + oz * ow) + cy;
 415                         nz = 2.0f * (ox * oz - oy * ow) + cz;
 416                         nw = 2.0f * (ox * ow + oy * oz) + cw;
 417                 }
 418
 419                 if (nx * nx + ny * ny + nz * nz + nw * nw > 4.0f)
 420                         return false;
 421
 422                 ox = nx;
 423                 oy = ny;
 424                 oz = nz;
 425                 ow = nw;
 426         }
 427
 428         return true;
 429 }
 430
 431
 432 s16 MapgenFractal::generateTerrain()
 433 {
 434         MapNode n_air(CONTENT_AIR);
 435         MapNode n_stone(c_stone);
 436         MapNode n_water(c_water_source);
 437
 438         s16 stone_surface_max_y = -MAX_MAP_GENERATION_LIMIT;
 439         u32 index2d = 0;
 440
 441         for (s16 z = node_min.Z; z <= node_max.Z; z++) {
 442                 for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
 443                         u32 vi = vm->m_area.index(node_min.X, y, z);
 444                         for (s16 x = node_min.X; x <= node_max.X; x++, vi++, index2d++) {
 445                                 if (vm->m_data[vi].getContent() == CONTENT_IGNORE) {
 446                                         s16 seabed_height = noise_seabed->result[index2d];
 447
 448                                         if (y <= seabed_height || getFractalAtPoint(x, y, z)) {
 449                                                 vm->m_data[vi] = n_stone;
 450                                                 if (y > stone_surface_max_y)
 451                                                         stone_surface_max_y = y;
 452                                         } else if (y <= water_level) {
 453                                                 vm->m_data[vi] = n_water;
 454                                         } else {
 455                                                 vm->m_data[vi] = n_air;
 456                                         }
 457                                 }
 458                         }
 459                         index2d -= ystride;
 460                 }
 461                 index2d += ystride;
 462         }
 463
 464         return stone_surface_max_y;
 465 }
 466
 467
 468 MgStoneType MapgenFractal::generateBiomes(float *heat_map, float *humidity_map)
 469 {
 470         v3s16 em = vm->m_area.getExtent();
 471         u32 index = 0;
 472         MgStoneType stone_type = STONE;
 473
 474         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 475         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
 476                 Biome *biome = NULL;
 477                 u16 depth_top = 0;
 478                 u16 base_filler = 0;
 479                 u16 depth_water_top = 0;
 480                 u32 vi = vm->m_area.index(x, node_max.Y, z);
 481
 482                 // Check node at base of mapchunk above, either a node of a previously
 483                 // generated mapchunk or if not, a node of overgenerated base terrain.
 484                 content_t c_above = vm->m_data[vi + em.X].getContent();
 485                 bool air_above = c_above == CONTENT_AIR;
 486                 bool water_above = c_above == c_water_source;
 487
 488                 // If there is air or water above enable top/filler placement, otherwise force
 489                 // nplaced to stone level by setting a number exceeding any possible filler depth.
 490                 u16 nplaced = (air_above || water_above) ? 0 : U16_MAX;
 491
 492
 493                 for (s16 y = node_max.Y; y >= node_min.Y; y--) {
 494                         content_t c = vm->m_data[vi].getContent();
 495
 496                         // Biome is recalculated each time an upper surface is detected while
 497                         // working down a column. The selected biome then remains in effect for
 498                         // all nodes below until the next surface and biome recalculation.
 499                         // Biome is recalculated:
 500                         // 1. At the surface of stone below air or water.
 501                         // 2. At the surface of water below air.
 502                         // 3. When stone or water is detected but biome has not yet been calculated.
 503                         if ((c == c_stone && (air_above || water_above || !biome)) ||
 504                                         (c == c_water_source && (air_above || !biome))) {
 505                                 biome = bmgr->getBiome(heat_map[index], humidity_map[index], y);
 506                                 depth_top = biome->depth_top;
 507                                 base_filler = MYMAX(depth_top + biome->depth_filler
 508                                         + noise_filler_depth->result[index], 0);
 509                                 depth_water_top = biome->depth_water_top;
 510
 511                                 // Detect stone type for dungeons during every biome calculation.
 512                                 // This is more efficient than detecting per-node and will not
 513                                 // miss any desert stone or sandstone biomes.
 514                                 if (biome->c_stone == c_desert_stone)
 515                                         stone_type = DESERT_STONE;
 516                                 else if (biome->c_stone == c_sandstone)
 517                                         stone_type = SANDSTONE;
 518                         }
 519
 520                         if (c == c_stone) {
 521                                 content_t c_below = vm->m_data[vi - em.X].getContent();
 522
 523                                 // If the node below isn't solid, make this node stone, so that
 524                                 // any top/filler nodes above are structurally supported.
 525                                 // This is done by aborting the cycle of top/filler placement
 526                                 // immediately by forcing nplaced to stone level.
 527                                 if (c_below == CONTENT_AIR || c_below == c_water_source)
 528                                         nplaced = U16_MAX;
 529
 530                                 if (nplaced < depth_top) {
 531                                         vm->m_data[vi] = MapNode(biome->c_top);
 532                                         nplaced++;
 533                                 } else if (nplaced < base_filler) {
 534                                         vm->m_data[vi] = MapNode(biome->c_filler);
 535                                         nplaced++;
 536                                 } else {
 537                                         vm->m_data[vi] = MapNode(biome->c_stone);
 538                                 }
 539
 540                                 air_above = false;
 541                                 water_above = false;
 542                         } else if (c == c_water_source) {
 543                                 vm->m_data[vi] = MapNode((y > (s32)(water_level - depth_water_top)) ?
 544                                                 biome->c_water_top : biome->c_water);
 545                                 nplaced = 0;  // Enable top/filler placement for next surface
 546                                 air_above = false;
 547                                 water_above = true;
 548                         } else if (c == CONTENT_AIR) {
 549                                 nplaced = 0;  // Enable top/filler placement for next surface
 550                                 air_above = true;
 551                                 water_above = false;
 552                         } else {  // Possible various nodes overgenerated from neighbouring mapchunks
 553                                 nplaced = U16_MAX;  // Disable top/filler placement
 554                                 air_above = false;
 555                                 water_above = false;
 556                         }
 557
 558                         vm->m_area.add_y(em, vi, -1);
 559                 }
 560         }
 561
 562         return stone_type;
 563 }
 564
 565
 566 void MapgenFractal::dustTopNodes()
 567 {
 568         if (node_max.Y < water_level)
 569                 return;
 570
 571         v3s16 em = vm->m_area.getExtent();
 572         u32 index = 0;
 573
 574         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 575         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
 576                 Biome *biome = (Biome *)bmgr->getRaw(biomemap[index]);
 577
 578                 if (biome->c_dust == CONTENT_IGNORE)
 579                         continue;
 580
 581                 u32 vi = vm->m_area.index(x, full_node_max.Y, z);
 582                 content_t c_full_max = vm->m_data[vi].getContent();
 583                 s16 y_start;
 584
 585                 if (c_full_max == CONTENT_AIR) {
 586                         y_start = full_node_max.Y - 1;
 587                 } else if (c_full_max == CONTENT_IGNORE) {
 588                         vi = vm->m_area.index(x, node_max.Y + 1, z);
 589                         content_t c_max = vm->m_data[vi].getContent();
 590
 591                         if (c_max == CONTENT_AIR)
 592                                 y_start = node_max.Y;
 593                         else
 594                                 continue;
 595                 } else {
 596                         continue;
 597                 }
 598
 599                 vi = vm->m_area.index(x, y_start, z);
 600                 for (s16 y = y_start; y >= node_min.Y - 1; y--) {
 601                         if (vm->m_data[vi].getContent() != CONTENT_AIR)
 602                                 break;
 603
 604                         vm->m_area.add_y(em, vi, -1);
 605                 }
 606
 607                 content_t c = vm->m_data[vi].getContent();
 608                 if (!ndef->get(c).buildable_to && c != CONTENT_IGNORE && c != biome->c_dust) {
 609                         vm->m_area.add_y(em, vi, 1);
 610                         vm->m_data[vi] = MapNode(biome->c_dust);
 611                 }
 612         }
 613 }
 614
 615
 616 void MapgenFractal::generateCaves(s16 max_stone_y)
 617 {
 618         if (max_stone_y >= node_min.Y) {
 619                 u32 index = 0;
 620
 621                 for (s16 z = node_min.Z; z <= node_max.Z; z++)
 622                 for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
 623                         u32 vi = vm->m_area.index(node_min.X, y, z);
 624                         for (s16 x = node_min.X; x <= node_max.X; x++, vi++, index++) {
 625                                 float d1 = contour(noise_cave1->result[index]);
 626                                 float d2 = contour(noise_cave2->result[index]);
 627                                 if (d1 * d2 > 0.4f) {
 628                                         content_t c = vm->m_data[vi].getContent();
 629                                         if (!ndef->get(c).is_ground_content || c == CONTENT_AIR)
 630                                                 continue;
 631
 632                                         vm->m_data[vi] = MapNode(CONTENT_AIR);
 633                                 }
 634                         }
 635                 }
 636         }
 637
 638         if (node_max.Y > MGFRACTAL_LARGE_CAVE_DEPTH)
 639                 return;
 640
 641         PseudoRandom ps(blockseed + 21343);
 642         u32 bruises_count = (ps.range(1, 4) == 1) ? ps.range(1, 2) : 0;
 643         for (u32 i = 0; i < bruises_count; i++) {
 644                 CaveV5 cave(this, &ps);
 645                 cave.makeCave(node_min, node_max, max_stone_y);
 646         }
 647 }