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         // 1-down overgeneration
  60         this->zstride_1d = csize.X * (csize.Y + 1);
  61
  62         this->heightmap = new s16[csize.X * csize.Z];
  63
  64         MapgenFractalParams *sp = (MapgenFractalParams *)params->sparams;
  65
  66         this->spflags    = sp->spflags;
  67         this->cave_width = sp->cave_width;
  68         this->fractal    = sp->fractal;
  69         this->iterations = sp->iterations;
  70         this->scale      = sp->scale;
  71         this->offset     = sp->offset;
  72         this->slice_w    = sp->slice_w;
  73         this->julia_x    = sp->julia_x;
  74         this->julia_y    = sp->julia_y;
  75         this->julia_z    = sp->julia_z;
  76         this->julia_w    = sp->julia_w;
  77
  78         //// 2D terrain noise
  79         noise_seabed       = new Noise(&sp->np_seabed, seed, csize.X, csize.Z);
  80         noise_filler_depth = new Noise(&sp->np_filler_depth, seed, csize.X, csize.Z);
  81
  82         //// 3D terrain noise
  83         // 1-down overgeneraion
  84         noise_cave1 = new Noise(&sp->np_cave1, seed, csize.X, csize.Y + 1, csize.Z);
  85         noise_cave2 = new Noise(&sp->np_cave2, seed, csize.X, csize.Y + 1, csize.Z);
  86
  87         //// Initialize biome generator
  88         biomegen = emerge->biomemgr->createBiomeGen(
  89                 BIOMEGEN_ORIGINAL, params->bparams, csize);
  90         biomemap = biomegen->biomemap;
  91
  92         this->formula = fractal / 2 + fractal % 2;
  93         this->julia   = fractal % 2 == 0;
  94
  95         //// Resolve nodes to be used
  96         c_stone                = ndef->getId("mapgen_stone");
  97         c_water_source         = ndef->getId("mapgen_water_source");
  98         c_lava_source          = ndef->getId("mapgen_lava_source");
  99         c_desert_stone         = ndef->getId("mapgen_desert_stone");
 100         c_ice                  = ndef->getId("mapgen_ice");
 101         c_sandstone            = ndef->getId("mapgen_sandstone");
 102
 103         c_cobble               = ndef->getId("mapgen_cobble");
 104         c_stair_cobble         = ndef->getId("mapgen_stair_cobble");
 105         c_mossycobble          = ndef->getId("mapgen_mossycobble");
 106         c_sandstonebrick       = ndef->getId("mapgen_sandstonebrick");
 107         c_stair_sandstonebrick = ndef->getId("mapgen_stair_sandstonebrick");
 108
 109         if (c_ice == CONTENT_IGNORE)
 110                 c_ice = CONTENT_AIR;
 111         if (c_mossycobble == CONTENT_IGNORE)
 112                 c_mossycobble = c_cobble;
 113         if (c_stair_cobble == CONTENT_IGNORE)
 114                 c_stair_cobble = c_cobble;
 115         if (c_sandstonebrick == CONTENT_IGNORE)
 116                 c_sandstonebrick = c_sandstone;
 117         if (c_stair_sandstonebrick == CONTENT_IGNORE)
 118                 c_stair_sandstonebrick = c_sandstone;
 119 }
 120
 121
 122 MapgenFractal::~MapgenFractal()
 123 {
 124         delete noise_seabed;
 125         delete noise_filler_depth;
 126         delete noise_cave1;
 127         delete noise_cave2;
 128
 129         delete biomegen;
 130
 131         delete[] heightmap;
 132 }
 133
 134
 135 MapgenFractalParams::MapgenFractalParams()
 136 {
 137         spflags    = 0;
 138         cave_width = 0.3;
 139         fractal    = 1;
 140         iterations = 11;
 141         scale      = v3f(4096.0, 1024.0, 4096.0);
 142         offset     = v3f(1.79, 0.0, 0.0);
 143         slice_w    = 0.0;
 144         julia_x    = 0.33;
 145         julia_y    = 0.33;
 146         julia_z    = 0.33;
 147         julia_w    = 0.33;
 148
 149         np_seabed       = NoiseParams(-14, 9,   v3f(600, 600, 600), 41900, 5, 0.6, 2.0);
 150         np_filler_depth = NoiseParams(0,   1.2, v3f(150, 150, 150), 261,   3, 0.7, 2.0);
 151         np_cave1        = NoiseParams(0,   12,  v3f(96,  96,  96),  52534, 4, 0.5, 2.0);
 152         np_cave2        = NoiseParams(0,   12,  v3f(96,  96,  96),  10325, 4, 0.5, 2.0);
 153 }
 154
 155
 156 void MapgenFractalParams::readParams(const Settings *settings)
 157 {
 158         settings->getFlagStrNoEx("mgfractal_spflags",  spflags, flagdesc_mapgen_fractal);
 159         settings->getFloatNoEx("mgfractal_cave_width", cave_width);
 160         settings->getU16NoEx("mgfractal_fractal",      fractal);
 161         settings->getU16NoEx("mgfractal_iterations",   iterations);
 162         settings->getV3FNoEx("mgfractal_scale",        scale);
 163         settings->getV3FNoEx("mgfractal_offset",       offset);
 164         settings->getFloatNoEx("mgfractal_slice_w",    slice_w);
 165         settings->getFloatNoEx("mgfractal_julia_x",    julia_x);
 166         settings->getFloatNoEx("mgfractal_julia_y",    julia_y);
 167         settings->getFloatNoEx("mgfractal_julia_z",    julia_z);
 168         settings->getFloatNoEx("mgfractal_julia_w",    julia_w);
 169
 170         settings->getNoiseParams("mgfractal_np_seabed",       np_seabed);
 171         settings->getNoiseParams("mgfractal_np_filler_depth", np_filler_depth);
 172         settings->getNoiseParams("mgfractal_np_cave1",        np_cave1);
 173         settings->getNoiseParams("mgfractal_np_cave2",        np_cave2);
 174 }
 175
 176
 177 void MapgenFractalParams::writeParams(Settings *settings) const
 178 {
 179         settings->setFlagStr("mgfractal_spflags",  spflags, flagdesc_mapgen_fractal, U32_MAX);
 180         settings->setFloat("mgfractal_cave_width", cave_width);
 181         settings->setU16("mgfractal_fractal",      fractal);
 182         settings->setU16("mgfractal_iterations",   iterations);
 183         settings->setV3F("mgfractal_scale",        scale);
 184         settings->setV3F("mgfractal_offset",       offset);
 185         settings->setFloat("mgfractal_slice_w",    slice_w);
 186         settings->setFloat("mgfractal_julia_x",    julia_x);
 187         settings->setFloat("mgfractal_julia_y",    julia_y);
 188         settings->setFloat("mgfractal_julia_z",    julia_z);
 189         settings->setFloat("mgfractal_julia_w",    julia_w);
 190
 191         settings->setNoiseParams("mgfractal_np_seabed",       np_seabed);
 192         settings->setNoiseParams("mgfractal_np_filler_depth", np_filler_depth);
 193         settings->setNoiseParams("mgfractal_np_cave1",        np_cave1);
 194         settings->setNoiseParams("mgfractal_np_cave2",        np_cave2);
 195 }
 196
 197
 198 /////////////////////////////////////////////////////////////////
 199
 200
 201 int MapgenFractal::getSpawnLevelAtPoint(v2s16 p)
 202 {
 203         bool solid_below = false;  // Dry solid node is present below to spawn on
 204         u8 air_count = 0;  // Consecutive air nodes above the dry solid node
 205         s16 seabed_level = NoisePerlin2D(&noise_seabed->np, p.X, p.Y, seed);
 206         // Seabed can rise above water_level or might be raised to create dry land
 207         s16 search_start = MYMAX(seabed_level, water_level + 1);
 208         if (seabed_level > water_level)
 209                 solid_below = true;
 210
 211         for (s16 y = search_start; y <= search_start + 128; y++) {
 212                 if (getFractalAtPoint(p.X, y, p.Y)) {  // Fractal node
 213                         solid_below = true;
 214                         air_count = 0;
 215                 } else if (solid_below) {  // Air above solid node
 216                         air_count++;
 217                         if (air_count == 2)
 218                                 return y - 2;
 219                 }
 220         }
 221
 222         return MAX_MAP_GENERATION_LIMIT;  // Unsuitable spawn point
 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         // Init biome generator, place biome-specific nodes, and build biomemap
 262         biomegen->calcBiomeNoise(node_min);
 263         biomegen->getBiomes(heightmap);
 264         MgStoneType stone_type = generateBiomes();
 265
 266         if (flags & MG_CAVES)
 267                 generateCaves(stone_surface_max_y);
 268
 269         if ((flags & MG_DUNGEONS) && (stone_surface_max_y >= node_min.Y)) {
 270                 DungeonParams dp;
 271
 272                 dp.np_rarity  = nparams_dungeon_rarity;
 273                 dp.np_density = nparams_dungeon_density;
 274                 dp.np_wetness = nparams_dungeon_wetness;
 275                 dp.c_water    = c_water_source;
 276                 if (stone_type == STONE) {
 277                         dp.c_cobble = c_cobble;
 278                         dp.c_moss   = c_mossycobble;
 279                         dp.c_stair  = c_stair_cobble;
 280
 281                         dp.diagonal_dirs = false;
 282                         dp.mossratio     = 3.0;
 283                         dp.holesize      = v3s16(1, 2, 1);
 284                         dp.roomsize      = v3s16(0, 0, 0);
 285                         dp.notifytype    = GENNOTIFY_DUNGEON;
 286                 } else if (stone_type == DESERT_STONE) {
 287                         dp.c_cobble = c_desert_stone;
 288                         dp.c_moss   = c_desert_stone;
 289                         dp.c_stair  = c_desert_stone;
 290
 291                         dp.diagonal_dirs = true;
 292                         dp.mossratio     = 0.0;
 293                         dp.holesize      = v3s16(2, 3, 2);
 294                         dp.roomsize      = v3s16(2, 5, 2);
 295                         dp.notifytype    = GENNOTIFY_TEMPLE;
 296                 } else if (stone_type == SANDSTONE) {
 297                         dp.c_cobble = c_sandstonebrick;
 298                         dp.c_moss   = c_sandstonebrick;
 299                         dp.c_stair  = c_sandstonebrick;
 300
 301                         dp.diagonal_dirs = false;
 302                         dp.mossratio     = 0.0;
 303                         dp.holesize      = v3s16(2, 2, 2);
 304                         dp.roomsize      = v3s16(2, 0, 2);
 305                         dp.notifytype    = GENNOTIFY_DUNGEON;
 306                 }
 307
 308                 DungeonGen dgen(this, &dp);
 309                 dgen.generate(blockseed, full_node_min, full_node_max);
 310         }
 311
 312         // Generate the registered decorations
 313         if (flags & MG_DECORATIONS)
 314                 m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
 315
 316         // Generate the registered ores
 317         m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max);
 318
 319         // Sprinkle some dust on top after everything else was generated
 320         dustTopNodes();
 321
 322         //printf("makeChunk: %dms\n", t.stop());
 323
 324         updateLiquid(&data->transforming_liquid, full_node_min, full_node_max);
 325
 326         if (flags & MG_LIGHT)
 327                 calcLighting(node_min - v3s16(0, 1, 0), node_max + v3s16(0, 1, 0),
 328                         full_node_min, full_node_max);
 329
 330         //setLighting(node_min - v3s16(1, 0, 1) * MAP_BLOCKSIZE,
 331         //                      node_max + v3s16(1, 0, 1) * MAP_BLOCKSIZE, 0xFF);
 332
 333         this->generating = false;
 334 }
 335
 336
 337 void MapgenFractal::calculateNoise()
 338 {
 339         //TimeTaker t("calculateNoise", NULL, PRECISION_MICRO);
 340         s16 x = node_min.X;
 341         s16 z = node_min.Z;
 342
 343         noise_seabed->perlinMap2D(x, z);
 344
 345         // Cave noises are calculated in generateCaves()
 346         // only if solid terrain is present in mapchunk
 347
 348         noise_filler_depth->perlinMap2D(x, z);
 349
 350         //printf("calculateNoise: %dus\n", t.stop());
 351 }
 352
 353
 354 bool MapgenFractal::getFractalAtPoint(s16 x, s16 y, s16 z)
 355 {
 356         float cx, cy, cz, cw, ox, oy, oz, ow;
 357
 358         if (julia) {  // Julia set
 359                 cx = julia_x;
 360                 cy = julia_y;
 361                 cz = julia_z;
 362                 cw = julia_w;
 363                 ox = (float)x / scale.X - offset.X;
 364                 oy = (float)y / scale.Y - offset.Y;
 365                 oz = (float)z / scale.Z - offset.Z;
 366                 ow = slice_w;
 367         } else {  // Mandelbrot set
 368                 cx = (float)x / scale.X - offset.X;
 369                 cy = (float)y / scale.Y - offset.Y;
 370                 cz = (float)z / scale.Z - offset.Z;
 371                 cw = slice_w;
 372                 ox = 0.0f;
 373                 oy = 0.0f;
 374                 oz = 0.0f;
 375                 ow = 0.0f;
 376         }
 377
 378         float nx = 0.0f;
 379         float ny = 0.0f;
 380         float nz = 0.0f;
 381         float nw = 0.0f;
 382
 383         for (u16 iter = 0; iter < iterations; iter++) {
 384
 385                 if (formula == 1) {  // 4D "Roundy"
 386                         nx = ox * ox - oy * oy - oz * oz - ow * ow + cx;
 387                         ny = 2.0f * (ox * oy + oz * ow) + cy;
 388                         nz = 2.0f * (ox * oz + oy * ow) + cz;
 389                         nw = 2.0f * (ox * ow + oy * oz) + cw;
 390                 } else if (formula == 2) {  // 4D "Squarry"
 391                         nx = ox * ox - oy * oy - oz * oz - ow * ow + cx;
 392                         ny = 2.0f * (ox * oy + oz * ow) + cy;
 393                         nz = 2.0f * (ox * oz + oy * ow) + cz;
 394                         nw = 2.0f * (ox * ow - oy * oz) + cw;
 395                 } else if (formula == 3) {  // 4D "Mandy Cousin"
 396                         nx = ox * ox - oy * oy - oz * oz + ow * ow + cx;
 397                         ny = 2.0f * (ox * oy + oz * ow) + cy;
 398                         nz = 2.0f * (ox * oz + oy * ow) + cz;
 399                         nw = 2.0f * (ox * ow + oy * oz) + cw;
 400                 } else if (formula == 4) {  // 4D "Variation"
 401                         nx = ox * ox - oy * oy - oz * oz - ow * ow + cx;
 402                         ny = 2.0f * (ox * oy + oz * ow) + cy;
 403                         nz = 2.0f * (ox * oz - oy * ow) + cz;
 404                         nw = 2.0f * (ox * ow + oy * oz) + cw;
 405                 } else if (formula == 5) {  // 3D "Mandelbrot/Mandelbar"
 406                         nx = ox * ox - oy * oy - oz * oz + cx;
 407                         ny = 2.0f * ox * oy + cy;
 408                         nz = -2.0f * ox * oz + cz;
 409                 } else if (formula == 6) {  // 3D "Christmas Tree"
 410                         // Altering the formula here is necessary to avoid division by zero
 411                         if (fabs(oz) < 0.000000001f) {
 412                                 nx = ox * ox - oy * oy - oz * oz + cx;
 413                                 ny = 2.0f * oy * ox + cy;
 414                                 nz = 4.0f * oz * ox + cz;
 415                         } else {
 416                                 float a = (2.0f * ox) / (sqrt(oy * oy + oz * oz));
 417                                 nx = ox * ox - oy * oy - oz * oz + cx;
 418                                 ny = a * (oy * oy - oz * oz) + cy;
 419                                 nz = a * 2.0f * oy * oz + cz;
 420                         }
 421                 } else if (formula == 7) {  // 3D "Mandelbulb"
 422                         if (fabs(oy) < 0.000000001f) {
 423                                 nx = ox * ox - oz * oz + cx;
 424                                 ny = cy;
 425                                 nz = -2.0f * oz * sqrt(ox * ox) + cz;
 426                         } else {
 427                                 float a = 1.0f - (oz * oz) / (ox * ox + oy * oy);
 428                                 nx = (ox * ox - oy * oy) * a + cx;
 429                                 ny = 2.0f * ox * oy * a + cy;
 430                                 nz = -2.0f * oz * sqrt(ox * ox + oy * oy) + cz;
 431                         }
 432                 } else if (formula == 8) {  // 3D "Cosine Mandelbulb"
 433                         if (fabs(oy) < 0.000000001f) {
 434                                 nx = 2.0f * ox * oz + cx;
 435                                 ny = 4.0f * oy * oz + cy;
 436                                 nz = oz * oz - ox * ox - oy * oy + cz;
 437                         } else {
 438                                 float a = (2.0f * oz) / sqrt(ox * ox + oy * oy);
 439                                 nx = (ox * ox - oy * oy) * a + cx;
 440                                 ny = 2.0f * ox * oy * a + cy;
 441                                 nz = oz * oz - ox * ox - oy * oy + cz;
 442                         }
 443                 } else if (formula == 9) {  // 4D "Mandelbulb"
 444                         float rxy = sqrt(ox * ox + oy * oy);
 445                         float rxyz = sqrt(ox * ox + oy * oy + oz * oz);
 446                         if (fabs(ow) < 0.000000001f && fabs(oz) < 0.000000001f) {
 447                                 nx = (ox * ox - oy * oy) + cx;
 448                                 ny = 2.0f * ox * oy + cy;
 449                                 nz = -2.0f * rxy * oz + cz;
 450                                 nw = 2.0f * rxyz * ow + cw;
 451                         } else {
 452                                 float a = 1.0f - (ow * ow) / (rxyz * rxyz);
 453                                 float b = a * (1.0f - (oz * oz) / (rxy * rxy));
 454                                 nx = (ox * ox - oy * oy) * b + cx;
 455                                 ny = 2.0f * ox * oy * b + cy;
 456                                 nz = -2.0f * rxy * oz * a + cz;
 457                                 nw = 2.0f * rxyz * ow + cw;
 458                         }
 459                 }
 460
 461                 if (nx * nx + ny * ny + nz * nz + nw * nw > 4.0f)
 462                         return false;
 463
 464                 ox = nx;
 465                 oy = ny;
 466                 oz = nz;
 467                 ow = nw;
 468         }
 469
 470         return true;
 471 }
 472
 473
 474 s16 MapgenFractal::generateTerrain()
 475 {
 476         MapNode n_air(CONTENT_AIR);
 477         MapNode n_stone(c_stone);
 478         MapNode n_water(c_water_source);
 479
 480         s16 stone_surface_max_y = -MAX_MAP_GENERATION_LIMIT;
 481         u32 index2d = 0;
 482
 483         for (s16 z = node_min.Z; z <= node_max.Z; z++) {
 484                 for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
 485                         u32 vi = vm->m_area.index(node_min.X, y, z);
 486                         for (s16 x = node_min.X; x <= node_max.X; x++, vi++, index2d++) {
 487                                 if (vm->m_data[vi].getContent() == CONTENT_IGNORE) {
 488                                         s16 seabed_height = noise_seabed->result[index2d];
 489
 490                                         if (y <= seabed_height || getFractalAtPoint(x, y, z)) {
 491                                                 vm->m_data[vi] = n_stone;
 492                                                 if (y > stone_surface_max_y)
 493                                                         stone_surface_max_y = y;
 494                                         } else if (y <= water_level) {
 495                                                 vm->m_data[vi] = n_water;
 496                                         } else {
 497                                                 vm->m_data[vi] = n_air;
 498                                         }
 499                                 }
 500                         }
 501                         index2d -= ystride;
 502                 }
 503                 index2d += ystride;
 504         }
 505
 506         return stone_surface_max_y;
 507 }
 508
 509
 510 MgStoneType MapgenFractal::generateBiomes()
 511 {
 512         v3s16 em = vm->m_area.getExtent();
 513         u32 index = 0;
 514         MgStoneType stone_type = STONE;
 515
 516         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 517         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
 518                 Biome *biome = NULL;
 519                 u16 depth_top = 0;
 520                 u16 base_filler = 0;
 521                 u16 depth_water_top = 0;
 522                 u32 vi = vm->m_area.index(x, node_max.Y, z);
 523
 524                 // Check node at base of mapchunk above, either a node of a previously
 525                 // generated mapchunk or if not, a node of overgenerated base terrain.
 526                 content_t c_above = vm->m_data[vi + em.X].getContent();
 527                 bool air_above = c_above == CONTENT_AIR;
 528                 bool water_above = c_above == c_water_source;
 529
 530                 // If there is air or water above enable top/filler placement, otherwise force
 531                 // nplaced to stone level by setting a number exceeding any possible filler depth.
 532                 u16 nplaced = (air_above || water_above) ? 0 : U16_MAX;
 533
 534
 535                 for (s16 y = node_max.Y; y >= node_min.Y; y--) {
 536                         content_t c = vm->m_data[vi].getContent();
 537
 538                         // Biome is recalculated each time an upper surface is detected while
 539                         // working down a column. The selected biome then remains in effect for
 540                         // all nodes below until the next surface and biome recalculation.
 541                         // Biome is recalculated:
 542                         // 1. At the surface of stone below air or water.
 543                         // 2. At the surface of water below air.
 544                         // 3. When stone or water is detected but biome has not yet been calculated.
 545                         if ((c == c_stone && (air_above || water_above || !biome)) ||
 546                                         (c == c_water_source && (air_above || !biome))) {
 547                                 biome = biomegen->getBiomeAtIndex(index, y);
 548
 549                                 depth_top = biome->depth_top;
 550                                 base_filler = MYMAX(depth_top + biome->depth_filler
 551                                         + noise_filler_depth->result[index], 0);
 552                                 depth_water_top = biome->depth_water_top;
 553
 554                                 // Detect stone type for dungeons during every biome calculation.
 555                                 // This is more efficient than detecting per-node and will not
 556                                 // miss any desert stone or sandstone biomes.
 557                                 if (biome->c_stone == c_desert_stone)
 558                                         stone_type = DESERT_STONE;
 559                                 else if (biome->c_stone == c_sandstone)
 560                                         stone_type = SANDSTONE;
 561                         }
 562
 563                         if (c == c_stone) {
 564                                 content_t c_below = vm->m_data[vi - em.X].getContent();
 565
 566                                 // If the node below isn't solid, make this node stone, so that
 567                                 // any top/filler nodes above are structurally supported.
 568                                 // This is done by aborting the cycle of top/filler placement
 569                                 // immediately by forcing nplaced to stone level.
 570                                 if (c_below == CONTENT_AIR || c_below == c_water_source)
 571                                         nplaced = U16_MAX;
 572
 573                                 if (nplaced < depth_top) {
 574                                         vm->m_data[vi] = MapNode(biome->c_top);
 575                                         nplaced++;
 576                                 } else if (nplaced < base_filler) {
 577                                         vm->m_data[vi] = MapNode(biome->c_filler);
 578                                         nplaced++;
 579                                 } else {
 580                                         vm->m_data[vi] = MapNode(biome->c_stone);
 581                                 }
 582
 583                                 air_above = false;
 584                                 water_above = false;
 585                         } else if (c == c_water_source) {
 586                                 vm->m_data[vi] = MapNode((y > (s32)(water_level - depth_water_top)) ?
 587                                                 biome->c_water_top : biome->c_water);
 588                                 nplaced = 0;  // Enable top/filler placement for next surface
 589                                 air_above = false;
 590                                 water_above = true;
 591                         } else if (c == CONTENT_AIR) {
 592                                 nplaced = 0;  // Enable top/filler placement for next surface
 593                                 air_above = true;
 594                                 water_above = false;
 595                         } else {  // Possible various nodes overgenerated from neighbouring mapchunks
 596                                 nplaced = U16_MAX;  // Disable top/filler placement
 597                                 air_above = false;
 598                                 water_above = false;
 599                         }
 600
 601                         vm->m_area.add_y(em, vi, -1);
 602                 }
 603         }
 604
 605         return stone_type;
 606 }
 607
 608
 609 void MapgenFractal::dustTopNodes()
 610 {
 611         if (node_max.Y < water_level)
 612                 return;
 613
 614         v3s16 em = vm->m_area.getExtent();
 615         u32 index = 0;
 616
 617         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 618         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
 619                 Biome *biome = (Biome *)bmgr->getRaw(biomemap[index]);
 620
 621                 if (biome->c_dust == CONTENT_IGNORE)
 622                         continue;
 623
 624                 u32 vi = vm->m_area.index(x, full_node_max.Y, z);
 625                 content_t c_full_max = vm->m_data[vi].getContent();
 626                 s16 y_start;
 627
 628                 if (c_full_max == CONTENT_AIR) {
 629                         y_start = full_node_max.Y - 1;
 630                 } else if (c_full_max == CONTENT_IGNORE) {
 631                         vi = vm->m_area.index(x, node_max.Y + 1, z);
 632                         content_t c_max = vm->m_data[vi].getContent();
 633
 634                         if (c_max == CONTENT_AIR)
 635                                 y_start = node_max.Y;
 636                         else
 637                                 continue;
 638                 } else {
 639                         continue;
 640                 }
 641
 642                 vi = vm->m_area.index(x, y_start, z);
 643                 for (s16 y = y_start; y >= node_min.Y - 1; y--) {
 644                         if (vm->m_data[vi].getContent() != CONTENT_AIR)
 645                                 break;
 646
 647                         vm->m_area.add_y(em, vi, -1);
 648                 }
 649
 650                 content_t c = vm->m_data[vi].getContent();
 651                 if (!ndef->get(c).buildable_to && c != CONTENT_IGNORE && c != biome->c_dust) {
 652                         vm->m_area.add_y(em, vi, 1);
 653                         vm->m_data[vi] = MapNode(biome->c_dust);
 654                 }
 655         }
 656 }
 657
 658
 659 void MapgenFractal::generateCaves(s16 max_stone_y)
 660 {
 661         if (max_stone_y < node_min.Y)
 662                 return;
 663
 664         noise_cave1->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
 665         noise_cave2->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
 666
 667         v3s16 em = vm->m_area.getExtent();
 668         u32 index2d = 0;
 669
 670         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 671         for (s16 x = node_min.X; x <= node_max.X; x++, index2d++) {
 672                 bool column_is_open = false;  // Is column open to overground
 673                 bool is_tunnel = false;  // Is tunnel or tunnel floor
 674                 u32 vi = vm->m_area.index(x, node_max.Y, z);
 675                 u32 index3d = (z - node_min.Z) * zstride_1d + csize.Y * ystride +
 676                         (x - node_min.X);
 677                 // Biome of column
 678                 Biome *biome = (Biome *)bmgr->getRaw(biomemap[index2d]);
 679
 680                 // Don't excavate the overgenerated stone at node_max.Y + 1,
 681                 // this creates a 'roof' over the tunnel, preventing light in
 682                 // tunnels at mapchunk borders when generating mapchunks upwards.
 683                 // This 'roof' is removed when the mapchunk above is generated.
 684                 for (s16 y = node_max.Y; y >= node_min.Y - 1; y--,
 685                                 index3d -= ystride,
 686                                 vm->m_area.add_y(em, vi, -1)) {
 687
 688                         content_t c = vm->m_data[vi].getContent();
 689                         if (c == CONTENT_AIR || c == biome->c_water_top ||
 690                                         c == biome->c_water) {
 691                                 column_is_open = true;
 692                                 continue;
 693                         }
 694                         // Ground
 695                         float d1 = contour(noise_cave1->result[index3d]);
 696                         float d2 = contour(noise_cave2->result[index3d]);
 697
 698                         if (d1 * d2 > cave_width && ndef->get(c).is_ground_content) {
 699                                 // In tunnel and ground content, excavate
 700                                 vm->m_data[vi] = MapNode(CONTENT_AIR);
 701                                 is_tunnel = true;
 702                         } else {
 703                                 // Not in tunnel or not ground content
 704                                 if (is_tunnel && column_is_open &&
 705                                                 (c == biome->c_filler || c == biome->c_stone))
 706                                         // Tunnel entrance floor
 707                                         vm->m_data[vi] = MapNode(biome->c_top);
 708
 709                                 column_is_open = false;
 710                                 is_tunnel = false;
 711                         }
 712                 }
 713         }
 714
 715         if (node_max.Y > MGFRACTAL_LARGE_CAVE_DEPTH)
 716                 return;
 717
 718         PseudoRandom ps(blockseed + 21343);
 719         u32 bruises_count = ps.range(0, 2);
 720         for (u32 i = 0; i < bruises_count; i++) {
 721                 CaveV5 cave(this, &ps);
 722                 cave.makeCave(node_min, node_max, max_stone_y);
 723         }
 724 }