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->fractal    = sp->fractal;
  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         this->formula = fractal / 2 + fractal % 2;
  81         this->julia   = fractal % 2 == 0;
  82
  83         //// 2D terrain noise
  84         noise_seabed       = new Noise(&sp->np_seabed, seed, csize.X, csize.Z);
  85         noise_filler_depth = new Noise(&sp->np_filler_depth, seed, csize.X, csize.Z);
  86
  87         //// 3D terrain noise
  88         noise_cave1 = new Noise(&sp->np_cave1, seed, csize.X, csize.Y + 2, csize.Z);
  89         noise_cave2 = new Noise(&sp->np_cave2, seed, csize.X, csize.Y + 2, csize.Z);
  90
  91         //// Biome noise
  92         noise_heat           = new Noise(&params->np_biome_heat,           seed, csize.X, csize.Z);
  93         noise_humidity       = new Noise(&params->np_biome_humidity,       seed, csize.X, csize.Z);
  94         noise_heat_blend     = new Noise(&params->np_biome_heat_blend,     seed, csize.X, csize.Z);
  95         noise_humidity_blend = new Noise(&params->np_biome_humidity_blend, seed, csize.X, csize.Z);
  96
  97         //// Resolve nodes to be used
  98         INodeDefManager *ndef = emerge->ndef;
  99
 100         c_stone                = ndef->getId("mapgen_stone");
 101         c_water_source         = ndef->getId("mapgen_water_source");
 102         c_lava_source          = ndef->getId("mapgen_lava_source");
 103         c_desert_stone         = ndef->getId("mapgen_desert_stone");
 104         c_ice                  = ndef->getId("mapgen_ice");
 105         c_sandstone            = ndef->getId("mapgen_sandstone");
 106
 107         c_cobble               = ndef->getId("mapgen_cobble");
 108         c_stair_cobble         = ndef->getId("mapgen_stair_cobble");
 109         c_mossycobble          = ndef->getId("mapgen_mossycobble");
 110         c_sandstonebrick       = ndef->getId("mapgen_sandstonebrick");
 111         c_stair_sandstonebrick = ndef->getId("mapgen_stair_sandstonebrick");
 112
 113         if (c_ice == CONTENT_IGNORE)
 114                 c_ice = CONTENT_AIR;
 115         if (c_mossycobble == CONTENT_IGNORE)
 116                 c_mossycobble = c_cobble;
 117         if (c_stair_cobble == CONTENT_IGNORE)
 118                 c_stair_cobble = c_cobble;
 119         if (c_sandstonebrick == CONTENT_IGNORE)
 120                 c_sandstonebrick = c_sandstone;
 121         if (c_stair_sandstonebrick == CONTENT_IGNORE)
 122                 c_stair_sandstonebrick = c_sandstone;
 123 }
 124
 125
 126 MapgenFractal::~MapgenFractal()
 127 {
 128         delete noise_seabed;
 129         delete noise_filler_depth;
 130         delete noise_cave1;
 131         delete noise_cave2;
 132
 133         delete noise_heat;
 134         delete noise_humidity;
 135         delete noise_heat_blend;
 136         delete noise_humidity_blend;
 137
 138         delete[] heightmap;
 139         delete[] biomemap;
 140 }
 141
 142
 143 MapgenFractalParams::MapgenFractalParams()
 144 {
 145         spflags = 0;
 146
 147         fractal = 1;
 148         iterations = 11;
 149         scale = v3f(4096.0, 1024.0, 4096.0);
 150         offset = v3f(1.79, 0.0, 0.0);
 151         slice_w = 0.0;
 152
 153         julia_x = 0.33;
 154         julia_y = 0.33;
 155         julia_z = 0.33;
 156         julia_w = 0.33;
 157
 158         np_seabed       = NoiseParams(-14, 9,   v3f(600, 600, 600), 41900, 5, 0.6, 2.0);
 159         np_filler_depth = NoiseParams(0,   1.2, v3f(150, 150, 150), 261,   3, 0.7, 2.0);
 160         np_cave1        = NoiseParams(0,   12,  v3f(96,  96,  96),  52534, 4, 0.5, 2.0);
 161         np_cave2        = NoiseParams(0,   12,  v3f(96,  96,  96),  10325, 4, 0.5, 2.0);
 162 }
 163
 164
 165 void MapgenFractalParams::readParams(const Settings *settings)
 166 {
 167         settings->getFlagStrNoEx("mgfractal_spflags", spflags, flagdesc_mapgen_fractal);
 168
 169         settings->getU16NoEx("mgfractal_fractal", fractal);
 170         settings->getU16NoEx("mgfractal_iterations", iterations);
 171         settings->getV3FNoEx("mgfractal_scale", scale);
 172         settings->getV3FNoEx("mgfractal_offset", offset);
 173         settings->getFloatNoEx("mgfractal_slice_w", slice_w);
 174
 175         settings->getFloatNoEx("mgfractal_julia_x", julia_x);
 176         settings->getFloatNoEx("mgfractal_julia_y", julia_y);
 177         settings->getFloatNoEx("mgfractal_julia_z", julia_z);
 178         settings->getFloatNoEx("mgfractal_julia_w", julia_w);
 179
 180         settings->getNoiseParams("mgfractal_np_seabed", np_seabed);
 181         settings->getNoiseParams("mgfractal_np_filler_depth", np_filler_depth);
 182         settings->getNoiseParams("mgfractal_np_cave1", np_cave1);
 183         settings->getNoiseParams("mgfractal_np_cave2", np_cave2);
 184 }
 185
 186
 187 void MapgenFractalParams::writeParams(Settings *settings) const
 188 {
 189         settings->setFlagStr("mgfractal_spflags", spflags, flagdesc_mapgen_fractal, U32_MAX);
 190
 191         settings->setU16("mgfractal_fractal", fractal);
 192         settings->setU16("mgfractal_iterations", iterations);
 193         settings->setV3F("mgfractal_scale", scale);
 194         settings->setV3F("mgfractal_offset", offset);
 195         settings->setFloat("mgfractal_slice_w", slice_w);
 196
 197         settings->setFloat("mgfractal_julia_x", julia_x);
 198         settings->setFloat("mgfractal_julia_y", julia_y);
 199         settings->setFloat("mgfractal_julia_z", julia_z);
 200         settings->setFloat("mgfractal_julia_w", julia_w);
 201
 202         settings->setNoiseParams("mgfractal_np_seabed", np_seabed);
 203         settings->setNoiseParams("mgfractal_np_filler_depth", np_filler_depth);
 204         settings->setNoiseParams("mgfractal_np_cave1", np_cave1);
 205         settings->setNoiseParams("mgfractal_np_cave2", np_cave2);
 206 }
 207
 208
 209 /////////////////////////////////////////////////////////////////
 210
 211
 212 int MapgenFractal::getGroundLevelAtPoint(v2s16 p)
 213 {
 214         s16 search_start = 128;
 215         s16 search_end = -128;
 216
 217         for (s16 y = search_start; y >= search_end; y--) {
 218                 if (getFractalAtPoint(p.X, y, p.Y))
 219                         return y;
 220         }
 221
 222         return -MAX_MAP_GENERATION_LIMIT;
 223 }
 224
 225
 226 void MapgenFractal::makeChunk(BlockMakeData *data)
 227 {
 228         // Pre-conditions
 229         assert(data->vmanip);
 230         assert(data->nodedef);
 231         assert(data->blockpos_requested.X >= data->blockpos_min.X &&
 232                 data->blockpos_requested.Y >= data->blockpos_min.Y &&
 233                 data->blockpos_requested.Z >= data->blockpos_min.Z);
 234         assert(data->blockpos_requested.X <= data->blockpos_max.X &&
 235                 data->blockpos_requested.Y <= data->blockpos_max.Y &&
 236                 data->blockpos_requested.Z <= data->blockpos_max.Z);
 237
 238         this->generating = true;
 239         this->vm   = data->vmanip;
 240         this->ndef = data->nodedef;
 241         //TimeTaker t("makeChunk");
 242
 243         v3s16 blockpos_min = data->blockpos_min;
 244         v3s16 blockpos_max = data->blockpos_max;
 245         node_min = blockpos_min * MAP_BLOCKSIZE;
 246         node_max = (blockpos_max + v3s16(1, 1, 1)) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
 247         full_node_min = (blockpos_min - 1) * MAP_BLOCKSIZE;
 248         full_node_max = (blockpos_max + 2) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
 249
 250         blockseed = getBlockSeed2(full_node_min, seed);
 251
 252         // Make some noise
 253         calculateNoise();
 254
 255         // Generate base terrain, mountains, and ridges with initial heightmaps
 256         s16 stone_surface_max_y = generateTerrain();
 257
 258         // Create heightmap
 259         updateHeightmap(node_min, node_max);
 260
 261         // Create biomemap at heightmap surface
 262         bmgr->calcBiomes(csize.X, csize.Z, noise_heat->result,
 263                 noise_humidity->result, heightmap, biomemap);
 264
 265         // Actually place the biome-specific nodes
 266         MgStoneType stone_type = generateBiomes(noise_heat->result, noise_humidity->result);
 267
 268         if (flags & MG_CAVES)
 269                 generateCaves(stone_surface_max_y);
 270
 271         if ((flags & MG_DUNGEONS) && (stone_surface_max_y >= node_min.Y)) {
 272                 DungeonParams dp;
 273
 274                 dp.np_rarity  = nparams_dungeon_rarity;
 275                 dp.np_density = nparams_dungeon_density;
 276                 dp.np_wetness = nparams_dungeon_wetness;
 277                 dp.c_water    = c_water_source;
 278                 if (stone_type == STONE) {
 279                         dp.c_cobble = c_cobble;
 280                         dp.c_moss   = c_mossycobble;
 281                         dp.c_stair  = c_stair_cobble;
 282
 283                         dp.diagonal_dirs = false;
 284                         dp.mossratio     = 3.0;
 285                         dp.holesize      = v3s16(1, 2, 1);
 286                         dp.roomsize      = v3s16(0, 0, 0);
 287                         dp.notifytype    = GENNOTIFY_DUNGEON;
 288                 } else if (stone_type == DESERT_STONE) {
 289                         dp.c_cobble = c_desert_stone;
 290                         dp.c_moss   = c_desert_stone;
 291                         dp.c_stair  = c_desert_stone;
 292
 293                         dp.diagonal_dirs = true;
 294                         dp.mossratio     = 0.0;
 295                         dp.holesize      = v3s16(2, 3, 2);
 296                         dp.roomsize      = v3s16(2, 5, 2);
 297                         dp.notifytype    = GENNOTIFY_TEMPLE;
 298                 } else if (stone_type == SANDSTONE) {
 299                         dp.c_cobble = c_sandstonebrick;
 300                         dp.c_moss   = c_sandstonebrick;
 301                         dp.c_stair  = c_sandstonebrick;
 302
 303                         dp.diagonal_dirs = false;
 304                         dp.mossratio     = 0.0;
 305                         dp.holesize      = v3s16(2, 2, 2);
 306                         dp.roomsize      = v3s16(2, 0, 2);
 307                         dp.notifytype    = GENNOTIFY_DUNGEON;
 308                 }
 309
 310                 DungeonGen dgen(this, &dp);
 311                 dgen.generate(blockseed, full_node_min, full_node_max);
 312         }
 313
 314         // Generate the registered decorations
 315         if (flags & MG_DECORATIONS)
 316                 m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
 317
 318         // Generate the registered ores
 319         m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max);
 320
 321         // Sprinkle some dust on top after everything else was generated
 322         dustTopNodes();
 323
 324         //printf("makeChunk: %dms\n", t.stop());
 325
 326         updateLiquid(&data->transforming_liquid, full_node_min, full_node_max);
 327
 328         if (flags & MG_LIGHT)
 329                 calcLighting(node_min - v3s16(0, 1, 0), node_max + v3s16(0, 1, 0),
 330                         full_node_min, full_node_max);
 331
 332         //setLighting(node_min - v3s16(1, 0, 1) * MAP_BLOCKSIZE,
 333         //                      node_max + v3s16(1, 0, 1) * MAP_BLOCKSIZE, 0xFF);
 334
 335         this->generating = false;
 336 }
 337
 338
 339 void MapgenFractal::calculateNoise()
 340 {
 341         //TimeTaker t("calculateNoise", NULL, PRECISION_MICRO);
 342         s16 x = node_min.X;
 343         s16 z = node_min.Z;
 344
 345         noise_seabed->perlinMap2D(x, z);
 346
 347         // Cave noises are calculated in generateCaves()
 348         // only if solid terrain is present in mapchunk
 349
 350         noise_filler_depth->perlinMap2D(x, z);
 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 (julia) {  // Julia set
 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 set
 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         float nx = 0.0f;
 392         float ny = 0.0f;
 393         float nz = 0.0f;
 394         float nw = 0.0f;
 395
 396         for (u16 iter = 0; iter < iterations; iter++) {
 397
 398                 if (formula == 1) {  // 4D "Roundy"
 399                         nx = ox * ox - oy * oy - oz * oz - ow * ow + cx;
 400                         ny = 2.0f * (ox * oy + oz * ow) + cy;
 401                         nz = 2.0f * (ox * oz + oy * ow) + cz;
 402                         nw = 2.0f * (ox * ow + oy * oz) + cw;
 403                 } else if (formula == 2) {  // 4D "Squarry"
 404                         nx = ox * ox - oy * oy - oz * oz - ow * ow + cx;
 405                         ny = 2.0f * (ox * oy + oz * ow) + cy;
 406                         nz = 2.0f * (ox * oz + oy * ow) + cz;
 407                         nw = 2.0f * (ox * ow - oy * oz) + cw;
 408                 } else if (formula == 3) {  // 4D "Mandy Cousin"
 409                         nx = ox * ox - oy * oy - oz * oz + ow * ow + cx;
 410                         ny = 2.0f * (ox * oy + oz * ow) + cy;
 411                         nz = 2.0f * (ox * oz + oy * ow) + cz;
 412                         nw = 2.0f * (ox * ow + oy * oz) + cw;
 413                 } else if (formula == 4) {  // 4D "Variation"
 414                         nx = ox * ox - oy * oy - oz * oz - ow * ow + cx;
 415                         ny = 2.0f * (ox * oy + oz * ow) + cy;
 416                         nz = 2.0f * (ox * oz - oy * ow) + cz;
 417                         nw = 2.0f * (ox * ow + oy * oz) + cw;
 418                 } else if (formula == 5) {  // 3D "Mandelbrot/Mandelbar"
 419                         nx = ox * ox - oy * oy - oz * oz + cx;
 420                         ny = 2.0f * ox * oy + cy;
 421                         nz = -2.0f * ox * oz + cz;
 422                 } else if (formula == 6) {  // 3D "Christmas Tree"
 423                         // Altering the formula here is necessary to avoid division by zero
 424                         if (fabs(oz) < 0.000000001f) {
 425                                 nx = ox * ox - oy * oy - oz * oz + cx;
 426                                 ny = 2.0f * oy * ox + cy;
 427                                 nz = 4.0f * oz * ox + cz;
 428                         } else {
 429                                 float a = (2.0f * ox) / (sqrt(oy * oy + oz * oz));
 430                                 nx = ox * ox - oy * oy - oz * oz + cx;
 431                                 ny = a * (oy * oy - oz * oz) + cy;
 432                                 nz = a * 2.0f * oy * oz + cz;
 433                         }
 434                 } else if (formula == 7) {  // 3D "Mandelbulb"
 435                         if (fabs(oy) < 0.000000001f) {
 436                                 nx = ox * ox - oz * oz + cx;
 437                                 ny = cy;
 438                                 nz = -2.0f * oz * sqrt(ox * ox) + cz;
 439                         } else {
 440                                 float a = 1.0f - (oz * oz) / (ox * ox + oy * oy);
 441                                 nx = (ox * ox - oy * oy) * a + cx;
 442                                 ny = 2.0f * ox * oy * a + cy;
 443                                 nz = -2.0f * oz * sqrt(ox * ox + oy * oy) + cz;
 444                         }
 445                 } else if (formula == 8) {  // 3D "Cosine Mandelbulb"
 446                         if (fabs(oy) < 0.000000001f) {
 447                                 nx = 2.0f * ox * oz + cx;
 448                                 ny = 4.0f * oy * oz + cy;
 449                                 nz = oz * oz - ox * ox - oy * oy + cz;
 450                         } else {
 451                                 float a = (2.0f * oz) / sqrt(ox * ox + oy * oy);
 452                                 nx = (ox * ox - oy * oy) * a + cx;
 453                                 ny = 2.0f * ox * oy * a + cy;
 454                                 nz = oz * oz - ox * ox - oy * oy + cz;
 455                         }
 456                 } else if (formula == 9) {  // 4D "Mandelbulb"
 457                         float rxy = sqrt(ox * ox + oy * oy);
 458                         float rxyz = sqrt(ox * ox + oy * oy + oz * oz);
 459                         if (fabs(ow) < 0.000000001f && fabs(oz) < 0.000000001f) {
 460                                 nx = (ox * ox - oy * oy) + cx;
 461                                 ny = 2.0f * ox * oy + cy;
 462                                 nz = -2.0f * rxy * oz + cz;
 463                                 nw = 2.0f * rxyz * ow + cw;
 464                         } else {
 465                                 float a = 1.0f - (ow * ow) / (rxyz * rxyz);
 466                                 float b = a * (1.0f - (oz * oz) / (rxy * rxy));
 467                                 nx = (ox * ox - oy * oy) * b + cx;
 468                                 ny = 2.0f * ox * oy * b + cy;
 469                                 nz = -2.0f * rxy * oz * a + cz;
 470                                 nw = 2.0f * rxyz * ow + cw;
 471                         }
 472                 }
 473
 474                 if (nx * nx + ny * ny + nz * nz + nw * nw > 4.0f)
 475                         return false;
 476
 477                 ox = nx;
 478                 oy = ny;
 479                 oz = nz;
 480                 ow = nw;
 481         }
 482
 483         return true;
 484 }
 485
 486
 487 s16 MapgenFractal::generateTerrain()
 488 {
 489         MapNode n_air(CONTENT_AIR);
 490         MapNode n_stone(c_stone);
 491         MapNode n_water(c_water_source);
 492
 493         s16 stone_surface_max_y = -MAX_MAP_GENERATION_LIMIT;
 494         u32 index2d = 0;
 495
 496         for (s16 z = node_min.Z; z <= node_max.Z; z++) {
 497                 for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
 498                         u32 vi = vm->m_area.index(node_min.X, y, z);
 499                         for (s16 x = node_min.X; x <= node_max.X; x++, vi++, index2d++) {
 500                                 if (vm->m_data[vi].getContent() == CONTENT_IGNORE) {
 501                                         s16 seabed_height = noise_seabed->result[index2d];
 502
 503                                         if (y <= seabed_height || getFractalAtPoint(x, y, z)) {
 504                                                 vm->m_data[vi] = n_stone;
 505                                                 if (y > stone_surface_max_y)
 506                                                         stone_surface_max_y = y;
 507                                         } else if (y <= water_level) {
 508                                                 vm->m_data[vi] = n_water;
 509                                         } else {
 510                                                 vm->m_data[vi] = n_air;
 511                                         }
 512                                 }
 513                         }
 514                         index2d -= ystride;
 515                 }
 516                 index2d += ystride;
 517         }
 518
 519         return stone_surface_max_y;
 520 }
 521
 522
 523 MgStoneType MapgenFractal::generateBiomes(float *heat_map, float *humidity_map)
 524 {
 525         v3s16 em = vm->m_area.getExtent();
 526         u32 index = 0;
 527         MgStoneType stone_type = STONE;
 528
 529         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 530         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
 531                 Biome *biome = NULL;
 532                 u16 depth_top = 0;
 533                 u16 base_filler = 0;
 534                 u16 depth_water_top = 0;
 535                 u32 vi = vm->m_area.index(x, node_max.Y, z);
 536
 537                 // Check node at base of mapchunk above, either a node of a previously
 538                 // generated mapchunk or if not, a node of overgenerated base terrain.
 539                 content_t c_above = vm->m_data[vi + em.X].getContent();
 540                 bool air_above = c_above == CONTENT_AIR;
 541                 bool water_above = c_above == c_water_source;
 542
 543                 // If there is air or water above enable top/filler placement, otherwise force
 544                 // nplaced to stone level by setting a number exceeding any possible filler depth.
 545                 u16 nplaced = (air_above || water_above) ? 0 : U16_MAX;
 546
 547
 548                 for (s16 y = node_max.Y; y >= node_min.Y; y--) {
 549                         content_t c = vm->m_data[vi].getContent();
 550
 551                         // Biome is recalculated each time an upper surface is detected while
 552                         // working down a column. The selected biome then remains in effect for
 553                         // all nodes below until the next surface and biome recalculation.
 554                         // Biome is recalculated:
 555                         // 1. At the surface of stone below air or water.
 556                         // 2. At the surface of water below air.
 557                         // 3. When stone or water is detected but biome has not yet been calculated.
 558                         if ((c == c_stone && (air_above || water_above || !biome)) ||
 559                                         (c == c_water_source && (air_above || !biome))) {
 560                                 biome = bmgr->getBiome(heat_map[index], humidity_map[index], y);
 561                                 depth_top = biome->depth_top;
 562                                 base_filler = MYMAX(depth_top + biome->depth_filler
 563                                         + noise_filler_depth->result[index], 0);
 564                                 depth_water_top = biome->depth_water_top;
 565
 566                                 // Detect stone type for dungeons during every biome calculation.
 567                                 // This is more efficient than detecting per-node and will not
 568                                 // miss any desert stone or sandstone biomes.
 569                                 if (biome->c_stone == c_desert_stone)
 570                                         stone_type = DESERT_STONE;
 571                                 else if (biome->c_stone == c_sandstone)
 572                                         stone_type = SANDSTONE;
 573                         }
 574
 575                         if (c == c_stone) {
 576                                 content_t c_below = vm->m_data[vi - em.X].getContent();
 577
 578                                 // If the node below isn't solid, make this node stone, so that
 579                                 // any top/filler nodes above are structurally supported.
 580                                 // This is done by aborting the cycle of top/filler placement
 581                                 // immediately by forcing nplaced to stone level.
 582                                 if (c_below == CONTENT_AIR || c_below == c_water_source)
 583                                         nplaced = U16_MAX;
 584
 585                                 if (nplaced < depth_top) {
 586                                         vm->m_data[vi] = MapNode(biome->c_top);
 587                                         nplaced++;
 588                                 } else if (nplaced < base_filler) {
 589                                         vm->m_data[vi] = MapNode(biome->c_filler);
 590                                         nplaced++;
 591                                 } else {
 592                                         vm->m_data[vi] = MapNode(biome->c_stone);
 593                                 }
 594
 595                                 air_above = false;
 596                                 water_above = false;
 597                         } else if (c == c_water_source) {
 598                                 vm->m_data[vi] = MapNode((y > (s32)(water_level - depth_water_top)) ?
 599                                                 biome->c_water_top : biome->c_water);
 600                                 nplaced = 0;  // Enable top/filler placement for next surface
 601                                 air_above = false;
 602                                 water_above = true;
 603                         } else if (c == CONTENT_AIR) {
 604                                 nplaced = 0;  // Enable top/filler placement for next surface
 605                                 air_above = true;
 606                                 water_above = false;
 607                         } else {  // Possible various nodes overgenerated from neighbouring mapchunks
 608                                 nplaced = U16_MAX;  // Disable top/filler placement
 609                                 air_above = false;
 610                                 water_above = false;
 611                         }
 612
 613                         vm->m_area.add_y(em, vi, -1);
 614                 }
 615         }
 616
 617         return stone_type;
 618 }
 619
 620
 621 void MapgenFractal::dustTopNodes()
 622 {
 623         if (node_max.Y < water_level)
 624                 return;
 625
 626         v3s16 em = vm->m_area.getExtent();
 627         u32 index = 0;
 628
 629         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 630         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
 631                 Biome *biome = (Biome *)bmgr->getRaw(biomemap[index]);
 632
 633                 if (biome->c_dust == CONTENT_IGNORE)
 634                         continue;
 635
 636                 u32 vi = vm->m_area.index(x, full_node_max.Y, z);
 637                 content_t c_full_max = vm->m_data[vi].getContent();
 638                 s16 y_start;
 639
 640                 if (c_full_max == CONTENT_AIR) {
 641                         y_start = full_node_max.Y - 1;
 642                 } else if (c_full_max == CONTENT_IGNORE) {
 643                         vi = vm->m_area.index(x, node_max.Y + 1, z);
 644                         content_t c_max = vm->m_data[vi].getContent();
 645
 646                         if (c_max == CONTENT_AIR)
 647                                 y_start = node_max.Y;
 648                         else
 649                                 continue;
 650                 } else {
 651                         continue;
 652                 }
 653
 654                 vi = vm->m_area.index(x, y_start, z);
 655                 for (s16 y = y_start; y >= node_min.Y - 1; y--) {
 656                         if (vm->m_data[vi].getContent() != CONTENT_AIR)
 657                                 break;
 658
 659                         vm->m_area.add_y(em, vi, -1);
 660                 }
 661
 662                 content_t c = vm->m_data[vi].getContent();
 663                 if (!ndef->get(c).buildable_to && c != CONTENT_IGNORE && c != biome->c_dust) {
 664                         vm->m_area.add_y(em, vi, 1);
 665                         vm->m_data[vi] = MapNode(biome->c_dust);
 666                 }
 667         }
 668 }
 669
 670
 671 void MapgenFractal::generateCaves(s16 max_stone_y)
 672 {
 673         if (max_stone_y < node_min.Y)
 674                 return;
 675
 676         noise_cave1->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
 677         noise_cave2->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
 678
 679         v3s16 em = vm->m_area.getExtent();
 680         u32 index2d = 0;
 681
 682         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 683         for (s16 x = node_min.X; x <= node_max.X; x++, index2d++) {
 684                 bool column_is_open = false;  // Is column open to overground
 685                 u32 vi = vm->m_area.index(x, node_max.Y + 1, z);
 686                 u32 index3d = (z - node_min.Z) * zstride + (csize.Y + 1) * ystride +
 687                         (x - node_min.X);
 688                 // Biome of column
 689                 Biome *biome = (Biome *)bmgr->getRaw(biomemap[index2d]);
 690
 691                 for (s16 y = node_max.Y + 1; y >= node_min.Y - 1;
 692                                 y--, index3d -= ystride, vm->m_area.add_y(em, vi, -1)) {
 693                         content_t c = vm->m_data[vi].getContent();
 694                         if (c == CONTENT_AIR || c == biome->c_water_top ||
 695                                         c == biome->c_water) {
 696                                 column_is_open = true;
 697                                 continue;
 698                         }
 699                         // Ground
 700                         float d1 = contour(noise_cave1->result[index3d]);
 701                         float d2 = contour(noise_cave2->result[index3d]);
 702                         if (d1 * d2 > 0.3f && ndef->get(c).is_ground_content) {
 703                                 // In tunnel and ground content, excavate
 704                                 vm->m_data[vi] = MapNode(CONTENT_AIR);
 705                         } else if (column_is_open &&
 706                                         (c == biome->c_filler || c == biome->c_stone)) {
 707                                 // Tunnel entrance floor
 708                                 vm->m_data[vi] = MapNode(biome->c_top);
 709                                 column_is_open = false;
 710                         } else {
 711                                 column_is_open = false;
 712                         }
 713                 }
 714         }
 715
 716         if (node_max.Y > MGFRACTAL_LARGE_CAVE_DEPTH)
 717                 return;
 718
 719         PseudoRandom ps(blockseed + 21343);
 720         u32 bruises_count = ps.range(0, 2);
 721         for (u32 i = 0; i < bruises_count; i++) {
 722                 CaveV5 cave(this, &ps);
 723                 cave.makeCave(node_min, node_max, max_stone_y);
 724         }
 725 }