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->biomemap  = new u8[csize.X * csize.Z];
  63         this->heightmap = new s16[csize.X * csize.Z];
  64         this->heatmap   = NULL;
  65         this->humidmap  = NULL;
  66
  67         MapgenFractalParams *sp = (MapgenFractalParams *)params->sparams;
  68
  69         this->spflags    = sp->spflags;
  70         this->cave_width = sp->cave_width;
  71         this->fractal    = sp->fractal;
  72         this->iterations = sp->iterations;
  73         this->scale      = sp->scale;
  74         this->offset     = sp->offset;
  75         this->slice_w    = sp->slice_w;
  76         this->julia_x    = sp->julia_x;
  77         this->julia_y    = sp->julia_y;
  78         this->julia_z    = sp->julia_z;
  79         this->julia_w    = sp->julia_w;
  80
  81         //// 2D terrain noise
  82         noise_seabed       = new Noise(&sp->np_seabed, seed, csize.X, csize.Z);
  83         noise_filler_depth = new Noise(&sp->np_filler_depth, seed, csize.X, csize.Z);
  84
  85         //// 3D terrain noise
  86         // 1-down overgeneraion
  87         noise_cave1 = new Noise(&sp->np_cave1, seed, csize.X, csize.Y + 1, csize.Z);
  88         noise_cave2 = new Noise(&sp->np_cave2, seed, csize.X, csize.Y + 1, csize.Z);
  89
  90         //// Biome noise
  91         noise_heat           = new Noise(&params->np_biome_heat,           seed, csize.X, csize.Z);
  92         noise_humidity       = new Noise(&params->np_biome_humidity,       seed, csize.X, csize.Z);
  93         noise_heat_blend     = new Noise(&params->np_biome_heat_blend,     seed, csize.X, csize.Z);
  94         noise_humidity_blend = new Noise(&params->np_biome_humidity_blend, seed, csize.X, csize.Z);
  95
  96         this->formula = fractal / 2 + fractal % 2;
  97         this->julia   = fractal % 2 == 0;
  98
  99         //// Resolve nodes to be used
 100         INodeDefManager *ndef = emerge->ndef;
 101
 102         c_stone                = ndef->getId("mapgen_stone");
 103         c_water_source         = ndef->getId("mapgen_water_source");
 104         c_lava_source          = ndef->getId("mapgen_lava_source");
 105         c_desert_stone         = ndef->getId("mapgen_desert_stone");
 106         c_ice                  = ndef->getId("mapgen_ice");
 107         c_sandstone            = ndef->getId("mapgen_sandstone");
 108
 109         c_cobble               = ndef->getId("mapgen_cobble");
 110         c_stair_cobble         = ndef->getId("mapgen_stair_cobble");
 111         c_mossycobble          = ndef->getId("mapgen_mossycobble");
 112         c_sandstonebrick       = ndef->getId("mapgen_sandstonebrick");
 113         c_stair_sandstonebrick = ndef->getId("mapgen_stair_sandstonebrick");
 114
 115         if (c_ice == CONTENT_IGNORE)
 116                 c_ice = CONTENT_AIR;
 117         if (c_mossycobble == CONTENT_IGNORE)
 118                 c_mossycobble = c_cobble;
 119         if (c_stair_cobble == CONTENT_IGNORE)
 120                 c_stair_cobble = c_cobble;
 121         if (c_sandstonebrick == CONTENT_IGNORE)
 122                 c_sandstonebrick = c_sandstone;
 123         if (c_stair_sandstonebrick == CONTENT_IGNORE)
 124                 c_stair_sandstonebrick = c_sandstone;
 125 }
 126
 127
 128 MapgenFractal::~MapgenFractal()
 129 {
 130         delete noise_seabed;
 131         delete noise_filler_depth;
 132         delete noise_cave1;
 133         delete noise_cave2;
 134
 135         delete noise_heat;
 136         delete noise_humidity;
 137         delete noise_heat_blend;
 138         delete noise_humidity_blend;
 139
 140         delete[] heightmap;
 141         delete[] biomemap;
 142 }
 143
 144
 145 MapgenFractalParams::MapgenFractalParams()
 146 {
 147         spflags    = 0;
 148         cave_width = 0.3;
 149         fractal    = 1;
 150         iterations = 11;
 151         scale      = v3f(4096.0, 1024.0, 4096.0);
 152         offset     = v3f(1.79, 0.0, 0.0);
 153         slice_w    = 0.0;
 154         julia_x    = 0.33;
 155         julia_y    = 0.33;
 156         julia_z    = 0.33;
 157         julia_w    = 0.33;
 158
 159         np_seabed       = NoiseParams(-14, 9,   v3f(600, 600, 600), 41900, 5, 0.6, 2.0);
 160         np_filler_depth = NoiseParams(0,   1.2, v3f(150, 150, 150), 261,   3, 0.7, 2.0);
 161         np_cave1        = NoiseParams(0,   12,  v3f(96,  96,  96),  52534, 4, 0.5, 2.0);
 162         np_cave2        = NoiseParams(0,   12,  v3f(96,  96,  96),  10325, 4, 0.5, 2.0);
 163 }
 164
 165
 166 void MapgenFractalParams::readParams(const Settings *settings)
 167 {
 168         settings->getFlagStrNoEx("mgfractal_spflags",  spflags, flagdesc_mapgen_fractal);
 169         settings->getFloatNoEx("mgfractal_cave_width", cave_width);
 170         settings->getU16NoEx("mgfractal_fractal",      fractal);
 171         settings->getU16NoEx("mgfractal_iterations",   iterations);
 172         settings->getV3FNoEx("mgfractal_scale",        scale);
 173         settings->getV3FNoEx("mgfractal_offset",       offset);
 174         settings->getFloatNoEx("mgfractal_slice_w",    slice_w);
 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         settings->setFloat("mgfractal_cave_width", cave_width);
 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         settings->setFloat("mgfractal_julia_x",    julia_x);
 197         settings->setFloat("mgfractal_julia_y",    julia_y);
 198         settings->setFloat("mgfractal_julia_z",    julia_z);
 199         settings->setFloat("mgfractal_julia_w",    julia_w);
 200
 201         settings->setNoiseParams("mgfractal_np_seabed",       np_seabed);
 202         settings->setNoiseParams("mgfractal_np_filler_depth", np_filler_depth);
 203         settings->setNoiseParams("mgfractal_np_cave1",        np_cave1);
 204         settings->setNoiseParams("mgfractal_np_cave2",        np_cave2);
 205 }
 206
 207
 208 /////////////////////////////////////////////////////////////////
 209
 210
 211 int MapgenFractal::getSpawnLevelAtPoint(v2s16 p)
 212 {
 213         bool solid_below = false;  // Dry solid node is present below to spawn on
 214         u8 air_count = 0;  // Consecutive air nodes above the dry solid node
 215         s16 seabed_level = NoisePerlin2D(&noise_seabed->np, p.X, p.Y, seed);
 216         // Seabed can rise above water_level or might be raised to create dry land
 217         s16 search_start = MYMAX(seabed_level, water_level + 1);
 218         if (seabed_level > water_level)
 219                 solid_below = true;
 220
 221         for (s16 y = search_start; y <= search_start + 128; y++) {
 222                 if (getFractalAtPoint(p.X, y, p.Y)) {  // Fractal node
 223                         solid_below = true;
 224                         air_count = 0;
 225                 } else if (solid_below) {  // Air above solid node
 226                         air_count++;
 227                         if (air_count == 2)
 228                                 return y - 2;
 229                 }
 230         }
 231
 232         return MAX_MAP_GENERATION_LIMIT;  // Unsuitable spawn point
 233 }
 234
 235
 236 void MapgenFractal::makeChunk(BlockMakeData *data)
 237 {
 238         // Pre-conditions
 239         assert(data->vmanip);
 240         assert(data->nodedef);
 241         assert(data->blockpos_requested.X >= data->blockpos_min.X &&
 242                 data->blockpos_requested.Y >= data->blockpos_min.Y &&
 243                 data->blockpos_requested.Z >= data->blockpos_min.Z);
 244         assert(data->blockpos_requested.X <= data->blockpos_max.X &&
 245                 data->blockpos_requested.Y <= data->blockpos_max.Y &&
 246                 data->blockpos_requested.Z <= data->blockpos_max.Z);
 247
 248         this->generating = true;
 249         this->vm   = data->vmanip;
 250         this->ndef = data->nodedef;
 251         //TimeTaker t("makeChunk");
 252
 253         v3s16 blockpos_min = data->blockpos_min;
 254         v3s16 blockpos_max = data->blockpos_max;
 255         node_min = blockpos_min * MAP_BLOCKSIZE;
 256         node_max = (blockpos_max + v3s16(1, 1, 1)) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
 257         full_node_min = (blockpos_min - 1) * MAP_BLOCKSIZE;
 258         full_node_max = (blockpos_max + 2) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
 259
 260         blockseed = getBlockSeed2(full_node_min, seed);
 261
 262         // Make some noise
 263         calculateNoise();
 264
 265         // Generate base terrain, mountains, and ridges with initial heightmaps
 266         s16 stone_surface_max_y = generateTerrain();
 267
 268         // Create heightmap
 269         updateHeightmap(node_min, node_max);
 270
 271         // Create biomemap at heightmap surface
 272         bmgr->calcBiomes(csize.X, csize.Z, noise_heat->result,
 273                 noise_humidity->result, heightmap, biomemap);
 274
 275         // Actually place the biome-specific nodes
 276         MgStoneType stone_type = generateBiomes(noise_heat->result, noise_humidity->result);
 277
 278         if (flags & MG_CAVES)
 279                 generateCaves(stone_surface_max_y);
 280
 281         if ((flags & MG_DUNGEONS) && (stone_surface_max_y >= node_min.Y)) {
 282                 DungeonParams dp;
 283
 284                 dp.np_rarity  = nparams_dungeon_rarity;
 285                 dp.np_density = nparams_dungeon_density;
 286                 dp.np_wetness = nparams_dungeon_wetness;
 287                 dp.c_water    = c_water_source;
 288                 if (stone_type == STONE) {
 289                         dp.c_cobble = c_cobble;
 290                         dp.c_moss   = c_mossycobble;
 291                         dp.c_stair  = c_stair_cobble;
 292
 293                         dp.diagonal_dirs = false;
 294                         dp.mossratio     = 3.0;
 295                         dp.holesize      = v3s16(1, 2, 1);
 296                         dp.roomsize      = v3s16(0, 0, 0);
 297                         dp.notifytype    = GENNOTIFY_DUNGEON;
 298                 } else if (stone_type == DESERT_STONE) {
 299                         dp.c_cobble = c_desert_stone;
 300                         dp.c_moss   = c_desert_stone;
 301                         dp.c_stair  = c_desert_stone;
 302
 303                         dp.diagonal_dirs = true;
 304                         dp.mossratio     = 0.0;
 305                         dp.holesize      = v3s16(2, 3, 2);
 306                         dp.roomsize      = v3s16(2, 5, 2);
 307                         dp.notifytype    = GENNOTIFY_TEMPLE;
 308                 } else if (stone_type == SANDSTONE) {
 309                         dp.c_cobble = c_sandstonebrick;
 310                         dp.c_moss   = c_sandstonebrick;
 311                         dp.c_stair  = c_sandstonebrick;
 312
 313                         dp.diagonal_dirs = false;
 314                         dp.mossratio     = 0.0;
 315                         dp.holesize      = v3s16(2, 2, 2);
 316                         dp.roomsize      = v3s16(2, 0, 2);
 317                         dp.notifytype    = GENNOTIFY_DUNGEON;
 318                 }
 319
 320                 DungeonGen dgen(this, &dp);
 321                 dgen.generate(blockseed, full_node_min, full_node_max);
 322         }
 323
 324         // Generate the registered decorations
 325         if (flags & MG_DECORATIONS)
 326                 m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
 327
 328         // Generate the registered ores
 329         m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max);
 330
 331         // Sprinkle some dust on top after everything else was generated
 332         dustTopNodes();
 333
 334         //printf("makeChunk: %dms\n", t.stop());
 335
 336         updateLiquid(&data->transforming_liquid, full_node_min, full_node_max);
 337
 338         if (flags & MG_LIGHT)
 339                 calcLighting(node_min - v3s16(0, 1, 0), node_max + v3s16(0, 1, 0),
 340                         full_node_min, full_node_max);
 341
 342         //setLighting(node_min - v3s16(1, 0, 1) * MAP_BLOCKSIZE,
 343         //                      node_max + v3s16(1, 0, 1) * MAP_BLOCKSIZE, 0xFF);
 344
 345         this->generating = false;
 346 }
 347
 348
 349 void MapgenFractal::calculateNoise()
 350 {
 351         //TimeTaker t("calculateNoise", NULL, PRECISION_MICRO);
 352         s16 x = node_min.X;
 353         s16 z = node_min.Z;
 354
 355         noise_seabed->perlinMap2D(x, z);
 356
 357         // Cave noises are calculated in generateCaves()
 358         // only if solid terrain is present in mapchunk
 359
 360         noise_filler_depth->perlinMap2D(x, z);
 361         noise_heat->perlinMap2D(x, z);
 362         noise_humidity->perlinMap2D(x, z);
 363         noise_heat_blend->perlinMap2D(x, z);
 364         noise_humidity_blend->perlinMap2D(x, z);
 365
 366         for (s32 i = 0; i < csize.X * csize.Z; i++) {
 367                 noise_heat->result[i] += noise_heat_blend->result[i];
 368                 noise_humidity->result[i] += noise_humidity_blend->result[i];
 369         }
 370
 371         heatmap = noise_heat->result;
 372         humidmap = noise_humidity->result;
 373         //printf("calculateNoise: %dus\n", t.stop());
 374 }
 375
 376
 377 bool MapgenFractal::getFractalAtPoint(s16 x, s16 y, s16 z)
 378 {
 379         float cx, cy, cz, cw, ox, oy, oz, ow;
 380
 381         if (julia) {  // Julia set
 382                 cx = julia_x;
 383                 cy = julia_y;
 384                 cz = julia_z;
 385                 cw = julia_w;
 386                 ox = (float)x / scale.X - offset.X;
 387                 oy = (float)y / scale.Y - offset.Y;
 388                 oz = (float)z / scale.Z - offset.Z;
 389                 ow = slice_w;
 390         } else {  // Mandelbrot set
 391                 cx = (float)x / scale.X - offset.X;
 392                 cy = (float)y / scale.Y - offset.Y;
 393                 cz = (float)z / scale.Z - offset.Z;
 394                 cw = slice_w;
 395                 ox = 0.0f;
 396                 oy = 0.0f;
 397                 oz = 0.0f;
 398                 ow = 0.0f;
 399         }
 400
 401         float nx = 0.0f;
 402         float ny = 0.0f;
 403         float nz = 0.0f;
 404         float nw = 0.0f;
 405
 406         for (u16 iter = 0; iter < iterations; iter++) {
 407
 408                 if (formula == 1) {  // 4D "Roundy"
 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 == 2) {  // 4D "Squarry"
 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 == 3) {  // 4D "Mandy Cousin"
 419                         nx = ox * ox - oy * oy - oz * oz + ow * ow + cx;
 420                         ny = 2.0f * (ox * oy + oz * ow) + cy;
 421                         nz = 2.0f * (ox * oz + oy * ow) + cz;
 422                         nw = 2.0f * (ox * ow + oy * oz) + cw;
 423                 } else if (formula == 4) {  // 4D "Variation"
 424                         nx = ox * ox - oy * oy - oz * oz - ow * ow + cx;
 425                         ny = 2.0f * (ox * oy + oz * ow) + cy;
 426                         nz = 2.0f * (ox * oz - oy * ow) + cz;
 427                         nw = 2.0f * (ox * ow + oy * oz) + cw;
 428                 } else if (formula == 5) {  // 3D "Mandelbrot/Mandelbar"
 429                         nx = ox * ox - oy * oy - oz * oz + cx;
 430                         ny = 2.0f * ox * oy + cy;
 431                         nz = -2.0f * ox * oz + cz;
 432                 } else if (formula == 6) {  // 3D "Christmas Tree"
 433                         // Altering the formula here is necessary to avoid division by zero
 434                         if (fabs(oz) < 0.000000001f) {
 435                                 nx = ox * ox - oy * oy - oz * oz + cx;
 436                                 ny = 2.0f * oy * ox + cy;
 437                                 nz = 4.0f * oz * ox + cz;
 438                         } else {
 439                                 float a = (2.0f * ox) / (sqrt(oy * oy + oz * oz));
 440                                 nx = ox * ox - oy * oy - oz * oz + cx;
 441                                 ny = a * (oy * oy - oz * oz) + cy;
 442                                 nz = a * 2.0f * oy * oz + cz;
 443                         }
 444                 } else if (formula == 7) {  // 3D "Mandelbulb"
 445                         if (fabs(oy) < 0.000000001f) {
 446                                 nx = ox * ox - oz * oz + cx;
 447                                 ny = cy;
 448                                 nz = -2.0f * oz * sqrt(ox * ox) + cz;
 449                         } else {
 450                                 float a = 1.0f - (oz * oz) / (ox * ox + oy * oy);
 451                                 nx = (ox * ox - oy * oy) * a + cx;
 452                                 ny = 2.0f * ox * oy * a + cy;
 453                                 nz = -2.0f * oz * sqrt(ox * ox + oy * oy) + cz;
 454                         }
 455                 } else if (formula == 8) {  // 3D "Cosine Mandelbulb"
 456                         if (fabs(oy) < 0.000000001f) {
 457                                 nx = 2.0f * ox * oz + cx;
 458                                 ny = 4.0f * oy * oz + cy;
 459                                 nz = oz * oz - ox * ox - oy * oy + cz;
 460                         } else {
 461                                 float a = (2.0f * oz) / sqrt(ox * ox + oy * oy);
 462                                 nx = (ox * ox - oy * oy) * a + cx;
 463                                 ny = 2.0f * ox * oy * a + cy;
 464                                 nz = oz * oz - ox * ox - oy * oy + cz;
 465                         }
 466                 } else if (formula == 9) {  // 4D "Mandelbulb"
 467                         float rxy = sqrt(ox * ox + oy * oy);
 468                         float rxyz = sqrt(ox * ox + oy * oy + oz * oz);
 469                         if (fabs(ow) < 0.000000001f && fabs(oz) < 0.000000001f) {
 470                                 nx = (ox * ox - oy * oy) + cx;
 471                                 ny = 2.0f * ox * oy + cy;
 472                                 nz = -2.0f * rxy * oz + cz;
 473                                 nw = 2.0f * rxyz * ow + cw;
 474                         } else {
 475                                 float a = 1.0f - (ow * ow) / (rxyz * rxyz);
 476                                 float b = a * (1.0f - (oz * oz) / (rxy * rxy));
 477                                 nx = (ox * ox - oy * oy) * b + cx;
 478                                 ny = 2.0f * ox * oy * b + cy;
 479                                 nz = -2.0f * rxy * oz * a + cz;
 480                                 nw = 2.0f * rxyz * ow + cw;
 481                         }
 482                 }
 483
 484                 if (nx * nx + ny * ny + nz * nz + nw * nw > 4.0f)
 485                         return false;
 486
 487                 ox = nx;
 488                 oy = ny;
 489                 oz = nz;
 490                 ow = nw;
 491         }
 492
 493         return true;
 494 }
 495
 496
 497 s16 MapgenFractal::generateTerrain()
 498 {
 499         MapNode n_air(CONTENT_AIR);
 500         MapNode n_stone(c_stone);
 501         MapNode n_water(c_water_source);
 502
 503         s16 stone_surface_max_y = -MAX_MAP_GENERATION_LIMIT;
 504         u32 index2d = 0;
 505
 506         for (s16 z = node_min.Z; z <= node_max.Z; z++) {
 507                 for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
 508                         u32 vi = vm->m_area.index(node_min.X, y, z);
 509                         for (s16 x = node_min.X; x <= node_max.X; x++, vi++, index2d++) {
 510                                 if (vm->m_data[vi].getContent() == CONTENT_IGNORE) {
 511                                         s16 seabed_height = noise_seabed->result[index2d];
 512
 513                                         if (y <= seabed_height || getFractalAtPoint(x, y, z)) {
 514                                                 vm->m_data[vi] = n_stone;
 515                                                 if (y > stone_surface_max_y)
 516                                                         stone_surface_max_y = y;
 517                                         } else if (y <= water_level) {
 518                                                 vm->m_data[vi] = n_water;
 519                                         } else {
 520                                                 vm->m_data[vi] = n_air;
 521                                         }
 522                                 }
 523                         }
 524                         index2d -= ystride;
 525                 }
 526                 index2d += ystride;
 527         }
 528
 529         return stone_surface_max_y;
 530 }
 531
 532
 533 MgStoneType MapgenFractal::generateBiomes(float *heat_map, float *humidity_map)
 534 {
 535         v3s16 em = vm->m_area.getExtent();
 536         u32 index = 0;
 537         MgStoneType stone_type = STONE;
 538
 539         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 540         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
 541                 Biome *biome = NULL;
 542                 u16 depth_top = 0;
 543                 u16 base_filler = 0;
 544                 u16 depth_water_top = 0;
 545                 u32 vi = vm->m_area.index(x, node_max.Y, z);
 546
 547                 // Check node at base of mapchunk above, either a node of a previously
 548                 // generated mapchunk or if not, a node of overgenerated base terrain.
 549                 content_t c_above = vm->m_data[vi + em.X].getContent();
 550                 bool air_above = c_above == CONTENT_AIR;
 551                 bool water_above = c_above == c_water_source;
 552
 553                 // If there is air or water above enable top/filler placement, otherwise force
 554                 // nplaced to stone level by setting a number exceeding any possible filler depth.
 555                 u16 nplaced = (air_above || water_above) ? 0 : U16_MAX;
 556
 557
 558                 for (s16 y = node_max.Y; y >= node_min.Y; y--) {
 559                         content_t c = vm->m_data[vi].getContent();
 560
 561                         // Biome is recalculated each time an upper surface is detected while
 562                         // working down a column. The selected biome then remains in effect for
 563                         // all nodes below until the next surface and biome recalculation.
 564                         // Biome is recalculated:
 565                         // 1. At the surface of stone below air or water.
 566                         // 2. At the surface of water below air.
 567                         // 3. When stone or water is detected but biome has not yet been calculated.
 568                         if ((c == c_stone && (air_above || water_above || !biome)) ||
 569                                         (c == c_water_source && (air_above || !biome))) {
 570                                 biome = bmgr->getBiome(heat_map[index], humidity_map[index], y);
 571                                 depth_top = biome->depth_top;
 572                                 base_filler = MYMAX(depth_top + biome->depth_filler
 573                                         + noise_filler_depth->result[index], 0);
 574                                 depth_water_top = biome->depth_water_top;
 575
 576                                 // Detect stone type for dungeons during every biome calculation.
 577                                 // This is more efficient than detecting per-node and will not
 578                                 // miss any desert stone or sandstone biomes.
 579                                 if (biome->c_stone == c_desert_stone)
 580                                         stone_type = DESERT_STONE;
 581                                 else if (biome->c_stone == c_sandstone)
 582                                         stone_type = SANDSTONE;
 583                         }
 584
 585                         if (c == c_stone) {
 586                                 content_t c_below = vm->m_data[vi - em.X].getContent();
 587
 588                                 // If the node below isn't solid, make this node stone, so that
 589                                 // any top/filler nodes above are structurally supported.
 590                                 // This is done by aborting the cycle of top/filler placement
 591                                 // immediately by forcing nplaced to stone level.
 592                                 if (c_below == CONTENT_AIR || c_below == c_water_source)
 593                                         nplaced = U16_MAX;
 594
 595                                 if (nplaced < depth_top) {
 596                                         vm->m_data[vi] = MapNode(biome->c_top);
 597                                         nplaced++;
 598                                 } else if (nplaced < base_filler) {
 599                                         vm->m_data[vi] = MapNode(biome->c_filler);
 600                                         nplaced++;
 601                                 } else {
 602                                         vm->m_data[vi] = MapNode(biome->c_stone);
 603                                 }
 604
 605                                 air_above = false;
 606                                 water_above = false;
 607                         } else if (c == c_water_source) {
 608                                 vm->m_data[vi] = MapNode((y > (s32)(water_level - depth_water_top)) ?
 609                                                 biome->c_water_top : biome->c_water);
 610                                 nplaced = 0;  // Enable top/filler placement for next surface
 611                                 air_above = false;
 612                                 water_above = true;
 613                         } else if (c == CONTENT_AIR) {
 614                                 nplaced = 0;  // Enable top/filler placement for next surface
 615                                 air_above = true;
 616                                 water_above = false;
 617                         } else {  // Possible various nodes overgenerated from neighbouring mapchunks
 618                                 nplaced = U16_MAX;  // Disable top/filler placement
 619                                 air_above = false;
 620                                 water_above = false;
 621                         }
 622
 623                         vm->m_area.add_y(em, vi, -1);
 624                 }
 625         }
 626
 627         return stone_type;
 628 }
 629
 630
 631 void MapgenFractal::dustTopNodes()
 632 {
 633         if (node_max.Y < water_level)
 634                 return;
 635
 636         v3s16 em = vm->m_area.getExtent();
 637         u32 index = 0;
 638
 639         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 640         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
 641                 Biome *biome = (Biome *)bmgr->getRaw(biomemap[index]);
 642
 643                 if (biome->c_dust == CONTENT_IGNORE)
 644                         continue;
 645
 646                 u32 vi = vm->m_area.index(x, full_node_max.Y, z);
 647                 content_t c_full_max = vm->m_data[vi].getContent();
 648                 s16 y_start;
 649
 650                 if (c_full_max == CONTENT_AIR) {
 651                         y_start = full_node_max.Y - 1;
 652                 } else if (c_full_max == CONTENT_IGNORE) {
 653                         vi = vm->m_area.index(x, node_max.Y + 1, z);
 654                         content_t c_max = vm->m_data[vi].getContent();
 655
 656                         if (c_max == CONTENT_AIR)
 657                                 y_start = node_max.Y;
 658                         else
 659                                 continue;
 660                 } else {
 661                         continue;
 662                 }
 663
 664                 vi = vm->m_area.index(x, y_start, z);
 665                 for (s16 y = y_start; y >= node_min.Y - 1; y--) {
 666                         if (vm->m_data[vi].getContent() != CONTENT_AIR)
 667                                 break;
 668
 669                         vm->m_area.add_y(em, vi, -1);
 670                 }
 671
 672                 content_t c = vm->m_data[vi].getContent();
 673                 if (!ndef->get(c).buildable_to && c != CONTENT_IGNORE && c != biome->c_dust) {
 674                         vm->m_area.add_y(em, vi, 1);
 675                         vm->m_data[vi] = MapNode(biome->c_dust);
 676                 }
 677         }
 678 }
 679
 680
 681 void MapgenFractal::generateCaves(s16 max_stone_y)
 682 {
 683         if (max_stone_y < node_min.Y)
 684                 return;
 685
 686         noise_cave1->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
 687         noise_cave2->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
 688
 689         v3s16 em = vm->m_area.getExtent();
 690         u32 index2d = 0;
 691
 692         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 693         for (s16 x = node_min.X; x <= node_max.X; x++, index2d++) {
 694                 bool column_is_open = false;  // Is column open to overground
 695                 bool is_tunnel = false;  // Is tunnel or tunnel floor
 696                 u32 vi = vm->m_area.index(x, node_max.Y, z);
 697                 u32 index3d = (z - node_min.Z) * zstride_1d + csize.Y * ystride +
 698                         (x - node_min.X);
 699                 // Biome of column
 700                 Biome *biome = (Biome *)bmgr->getRaw(biomemap[index2d]);
 701
 702                 // Don't excavate the overgenerated stone at node_max.Y + 1,
 703                 // this creates a 'roof' over the tunnel, preventing light in
 704                 // tunnels at mapchunk borders when generating mapchunks upwards.
 705                 // This 'roof' is removed when the mapchunk above is generated.
 706                 for (s16 y = node_max.Y; y >= node_min.Y - 1; y--,
 707                                 index3d -= ystride,
 708                                 vm->m_area.add_y(em, vi, -1)) {
 709
 710                         content_t c = vm->m_data[vi].getContent();
 711                         if (c == CONTENT_AIR || c == biome->c_water_top ||
 712                                         c == biome->c_water) {
 713                                 column_is_open = true;
 714                                 continue;
 715                         }
 716                         // Ground
 717                         float d1 = contour(noise_cave1->result[index3d]);
 718                         float d2 = contour(noise_cave2->result[index3d]);
 719
 720                         if (d1 * d2 > cave_width && ndef->get(c).is_ground_content) {
 721                                 // In tunnel and ground content, excavate
 722                                 vm->m_data[vi] = MapNode(CONTENT_AIR);
 723                                 is_tunnel = true;
 724                         } else {
 725                                 // Not in tunnel or not ground content
 726                                 if (is_tunnel && column_is_open &&
 727                                                 (c == biome->c_filler || c == biome->c_stone))
 728                                         // Tunnel entrance floor
 729                                         vm->m_data[vi] = MapNode(biome->c_top);
 730
 731                                 column_is_open = false;
 732                                 is_tunnel = false;
 733                         }
 734                 }
 735         }
 736
 737         if (node_max.Y > MGFRACTAL_LARGE_CAVE_DEPTH)
 738                 return;
 739
 740         PseudoRandom ps(blockseed + 21343);
 741         u32 bruises_count = ps.range(0, 2);
 742         for (u32 i = 0; i < bruises_count; i++) {
 743                 CaveV5 cave(this, &ps);
 744                 cave.makeCave(node_min, node_max, max_stone_y);
 745         }
 746 }