src/mapgen_v7.cpp

   1 /*
   2 Minetest
   3 Copyright (C) 2010-2013 kwolekr, Ryan Kwolek <kwolekr@minetest.net>
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU Lesser General Public License as published by
   7 the Free Software Foundation; either version 2.1 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU Lesser General Public License for more details.
  14
  15 You should have received a copy of the GNU Lesser General Public License along
  16 with this program; if not, write to the Free Software Foundation, Inc.,
  17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19
  20
  21 #include "mapgen.h"
  22 #include "voxel.h"
  23 #include "noise.h"
  24 #include "mapblock.h"
  25 #include "mapnode.h"
  26 #include "map.h"
  27 #include "content_sao.h"
  28 #include "nodedef.h"
  29 #include "voxelalgorithms.h"
  30 #include "profiler.h"
  31 #include "settings.h" // For g_settings
  32 #include "main.h" // For g_profiler
  33 #include "emerge.h"
  34 #include "dungeongen.h"
  35 #include "cavegen.h"
  36 #include "treegen.h"
  37 #include "biome.h"
  38 #include "mapgen_v7.h"
  39
  40
  41 /////////////////// Mapgen V7 perlin noise default values
  42 NoiseParams nparams_v7_def_terrain_base =
  43         {4, 70, v3f(300, 300, 300), 82341, 6, 0.7};
  44 NoiseParams nparams_v7_def_terrain_alt =
  45         {4, 25, v3f(600, 600, 600), 5934, 5, 0.6};
  46 NoiseParams nparams_v7_def_terrain_persist =
  47         {0.6, 0.1, v3f(500, 500, 500), 539, 3, 0.6};
  48 NoiseParams nparams_v7_def_height_select =
  49         {-0.5, 1, v3f(250, 250, 250), 4213, 5, 0.69};
  50
  51 NoiseParams nparams_v7_def_filler_depth =
  52         {0, 1.2, v3f(150, 150, 150), 261, 4, 0.7};
  53
  54 NoiseParams nparams_v7_def_mount_height =
  55         {100, 30, v3f(500, 500, 500), 72449, 4, 0.6};
  56 NoiseParams nparams_v7_def_ridge_uwater =
  57         {0, 1, v3f(500, 500, 500), 85039, 4, 0.6};
  58 NoiseParams nparams_v7_def_mountain =
  59         {0, 1, v3f(250, 350, 250), 5333, 5, 0.68};
  60 NoiseParams nparams_v7_def_ridge =
  61         {0, 1, v3f(100, 100, 100), 6467, 4, 0.75};
  62
  63
  64 ///////////////////////////////////////////////////////////////////////////////
  65
  66
  67 MapgenV7::MapgenV7(int mapgenid, MapgenV7Params *params, EmergeManager *emerge) {
  68         this->generating  = false;
  69         this->id     = mapgenid;
  70         this->emerge = emerge;
  71         this->bmgr   = emerge->biomedef;
  72
  73         this->seed     = (int)params->seed;
  74         this->water_level = params->water_level;
  75         this->flags    = params->flags | MGV7_MOUNTAINS | MGV7_RIDGES;
  76
  77         this->csize   = v3s16(1, 1, 1) * params->chunksize * MAP_BLOCKSIZE;
  78
  79         // amount of elements to skip for the next index
  80         // for noise/height/biome maps (not vmanip)
  81         this->ystride = csize.X;
  82         this->zstride = csize.X * csize.Y;
  83
  84         this->biomemap  = new u8[csize.X * csize.Z];
  85         this->heightmap = new s16[csize.X * csize.Z];
  86         this->ridge_heightmap = new s16[csize.X * csize.Z];
  87
  88         // Terrain noise
  89         noise_terrain_base    = new Noise(&params->np_terrain_base,    seed, csize.X, csize.Z);
  90         noise_terrain_alt     = new Noise(&params->np_terrain_alt,     seed, csize.X, csize.Z);
  91         noise_terrain_persist = new Noise(&params->np_terrain_persist, seed, csize.X, csize.Z);
  92         noise_height_select   = new Noise(&params->np_height_select,   seed, csize.X, csize.Z);
  93         noise_filler_depth    = new Noise(&params->np_filler_depth,    seed, csize.X, csize.Z);
  94         noise_mount_height    = new Noise(&params->np_mount_height,    seed, csize.X, csize.Z);
  95         noise_ridge_uwater    = new Noise(&params->np_ridge_uwater,    seed, csize.X, csize.Z);
  96
  97         // 3d terrain noise
  98         noise_mountain = new Noise(&params->np_mountain, seed, csize.X, csize.Y, csize.Z);
  99         noise_ridge    = new Noise(&params->np_ridge,    seed, csize.X, csize.Y, csize.Z);
 100
 101         // Biome noise
 102         noise_heat     = new Noise(bmgr->np_heat,     seed, csize.X, csize.Z);
 103         noise_humidity = new Noise(bmgr->np_humidity, seed, csize.X, csize.Z);
 104 }
 105
 106
 107 MapgenV7::~MapgenV7() {
 108         delete noise_terrain_base;
 109         delete noise_terrain_persist;
 110         delete noise_height_select;
 111         delete noise_terrain_alt;
 112         delete noise_filler_depth;
 113         delete noise_mount_height;
 114         delete noise_ridge_uwater;
 115         delete noise_mountain;
 116         delete noise_ridge;
 117
 118         delete noise_heat;
 119         delete noise_humidity;
 120
 121         delete[] ridge_heightmap;
 122         delete[] heightmap;
 123         delete[] biomemap;
 124 }
 125
 126
 127 int MapgenV7::getGroundLevelAtPoint(v2s16 p) {
 128         // Base terrain calculation
 129         s16 y = baseTerrainLevelAtPoint(p.X, p.Y);
 130
 131         // Ridge/river terrain calculation
 132         float width = 0.3;
 133         float uwatern = NoisePerlin2DNoTxfm(noise_ridge_uwater->np, p.X, p.Y, seed) * 2;
 134         // actually computing the depth of the ridge is much more expensive;
 135         // if inside a river, simply guess
 136         if (uwatern >= -width && uwatern <= width)
 137                 return water_level - 10;
 138
 139         // Mountain terrain calculation
 140         int iters = 128; // don't even bother iterating more than 128 times..
 141         while (iters--) {
 142                 //current point would have been air
 143                 if (!getMountainTerrainAtPoint(p.X, y, p.Y))
 144                         return y;
 145
 146                 y++;
 147         }
 148
 149         return y;
 150 }
 151
 152
 153 void MapgenV7::makeChunk(BlockMakeData *data) {
 154         assert(data->vmanip);
 155         assert(data->nodedef);
 156         assert(data->blockpos_requested.X >= data->blockpos_min.X &&
 157                    data->blockpos_requested.Y >= data->blockpos_min.Y &&
 158                    data->blockpos_requested.Z >= data->blockpos_min.Z);
 159         assert(data->blockpos_requested.X <= data->blockpos_max.X &&
 160                    data->blockpos_requested.Y <= data->blockpos_max.Y &&
 161                    data->blockpos_requested.Z <= data->blockpos_max.Z);
 162
 163         this->generating = true;
 164         this->vm   = data->vmanip;
 165         this->ndef = data->nodedef;
 166         //TimeTaker t("makeChunk");
 167
 168         v3s16 blockpos_min = data->blockpos_min;
 169         v3s16 blockpos_max = data->blockpos_max;
 170         node_min = blockpos_min * MAP_BLOCKSIZE;
 171         node_max = (blockpos_max + v3s16(1, 1, 1)) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
 172         full_node_min = (blockpos_min - 1) * MAP_BLOCKSIZE;
 173         full_node_max = (blockpos_max + 2) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
 174
 175         blockseed = emerge->getBlockSeed(full_node_min);  //////use getBlockSeed2()!
 176
 177         c_stone           = ndef->getId("mapgen_stone");
 178         c_dirt            = ndef->getId("mapgen_dirt");
 179         c_dirt_with_grass = ndef->getId("mapgen_dirt_with_grass");
 180         c_sand            = ndef->getId("mapgen_sand");
 181         c_water_source    = ndef->getId("mapgen_water_source");
 182         c_lava_source     = ndef->getId("mapgen_lava_source");
 183         c_ice             = ndef->getId("default:ice");
 184         if (c_ice == CONTENT_IGNORE)
 185                 c_ice = CONTENT_AIR;
 186
 187         // Make some noise
 188         calculateNoise();
 189
 190         // Generate base terrain, mountains, and ridges with initial heightmaps
 191         s16 stone_surface_max_y = generateTerrain();
 192
 193         updateHeightmap(node_min, node_max);
 194
 195         // Calculate biomes
 196         BiomeNoiseInput binput;
 197         binput.mapsize      = v2s16(csize.X, csize.Z);
 198         binput.heat_map     = noise_heat->result;
 199         binput.humidity_map = noise_humidity->result;
 200         binput.height_map   = heightmap;
 201         bmgr->calcBiomes(&binput, biomemap);
 202
 203         // Actually place the biome-specific nodes and what not
 204         generateBiomes();
 205
 206         if (flags & MG_CAVES)
 207                 generateCaves(stone_surface_max_y);
 208
 209         if (flags & MG_DUNGEONS) {
 210                 DungeonGen dgen(ndef, data->seed, water_level);
 211                 dgen.generate(vm, blockseed, full_node_min, full_node_max);
 212         }
 213
 214         for (size_t i = 0; i != emerge->decorations.size(); i++) {
 215                 Decoration *deco = emerge->decorations[i];
 216                 deco->placeDeco(this, blockseed + i, node_min, node_max);
 217         }
 218
 219         for (size_t i = 0; i != emerge->ores.size(); i++) {
 220                 Ore *ore = emerge->ores[i];
 221                 ore->placeOre(this, blockseed + i, node_min, node_max);
 222         }
 223
 224         // Sprinkle some dust on top after everything else was generated
 225         dustTopNodes();
 226
 227         //printf("makeChunk: %dms\n", t.stop());
 228
 229         updateLiquid(&data->transforming_liquid, full_node_min, full_node_max);
 230
 231         if (!(flags & MG_NOLIGHT))
 232                 calcLighting(node_min - v3s16(1, 0, 1) * MAP_BLOCKSIZE,
 233                                          node_max + v3s16(1, 0, 1) * MAP_BLOCKSIZE);
 234         //setLighting(node_min - v3s16(1, 0, 1) * MAP_BLOCKSIZE,
 235         //                      node_max + v3s16(1, 0, 1) * MAP_BLOCKSIZE, 0xFF);
 236
 237         this->generating = false;
 238 }
 239
 240
 241 void MapgenV7::calculateNoise() {
 242         //TimeTaker t("calculateNoise", NULL, PRECISION_MICRO);
 243         int x = node_min.X;
 244         int y = node_min.Y;
 245         int z = node_min.Z;
 246
 247         noise_height_select->perlinMap2D(x, z);
 248         noise_height_select->transformNoiseMap();
 249
 250         noise_terrain_persist->perlinMap2D(x, z);
 251         noise_terrain_persist->transformNoiseMap();
 252         float *persistmap = noise_terrain_persist->result;
 253         for (int i = 0; i != csize.X * csize.Z; i++)
 254                 persistmap[i] = rangelim(persistmap[i], 0.4, 0.9);
 255
 256         noise_terrain_base->perlinMap2DModulated(x, z, persistmap);
 257         noise_terrain_base->transformNoiseMap();
 258
 259         noise_terrain_alt->perlinMap2DModulated(x, z, persistmap);
 260         noise_terrain_alt->transformNoiseMap();
 261
 262         noise_filler_depth->perlinMap2D(x, z);
 263
 264         if (flags & MGV7_MOUNTAINS) {
 265                 noise_mountain->perlinMap3D(x, y, z);
 266                 noise_mount_height->perlinMap2D(x, z);
 267                 noise_mount_height->transformNoiseMap();
 268         }
 269
 270         if (flags & MGV7_RIDGES) {
 271                 noise_ridge->perlinMap3D(x, y, z);
 272                 noise_ridge_uwater->perlinMap2D(x, z);
 273         }
 274
 275         noise_heat->perlinMap2D(x, z);
 276         noise_humidity->perlinMap2D(x, z);
 277
 278         //printf("calculateNoise: %dus\n", t.stop());
 279 }
 280
 281
 282 Biome *MapgenV7::getBiomeAtPoint(v3s16 p) {
 283         float heat      = NoisePerlin2D(bmgr->np_heat, p.X, p.Z, seed);
 284         float humidity  = NoisePerlin2D(bmgr->np_humidity, p.X, p.Z, seed);
 285         s16 groundlevel = baseTerrainLevelAtPoint(p.X, p.Z);
 286
 287         return bmgr->getBiome(heat, humidity, groundlevel);
 288 }
 289
 290 //needs to be updated
 291 float MapgenV7::baseTerrainLevelAtPoint(int x, int z) {
 292         float hselect = NoisePerlin2D(noise_height_select->np, x, z, seed);
 293         hselect = rangelim(hselect, 0.0, 1.0);
 294
 295         float persist = NoisePerlin2D(noise_terrain_persist->np, x, z, seed);
 296         persist = rangelim(persist, 0.4, 0.9);
 297
 298         noise_terrain_base->np->persist = persist;
 299         float height_base = NoisePerlin2D(noise_terrain_base->np, x, z, seed);
 300
 301         noise_terrain_alt->np->persist = persist;
 302         float height_alt = NoisePerlin2D(noise_terrain_alt->np, x, z, seed);
 303
 304         if (height_alt > height_base)
 305                 return height_alt;
 306
 307         return (height_base * hselect) + (height_alt * (1.0 - hselect));
 308 }
 309
 310
 311 float MapgenV7::baseTerrainLevelFromMap(int index) {
 312         float hselect     = rangelim(noise_height_select->result[index], 0.0, 1.0);
 313         float height_base = noise_terrain_base->result[index];
 314         float height_alt  = noise_terrain_alt->result[index];
 315
 316         if (height_alt > height_base)
 317                 return height_alt;
 318
 319         return (height_base * hselect) + (height_alt * (1.0 - hselect));
 320 }
 321
 322
 323 bool MapgenV7::getMountainTerrainAtPoint(int x, int y, int z) {
 324         float mnt_h_n = NoisePerlin2D(noise_mount_height->np, x, z, seed);
 325         float height_modifier = -((float)y / rangelim(mnt_h_n, 80.0, 150.0));
 326         float mnt_n = NoisePerlin3D(noise_mountain->np, x, y, z, seed);
 327
 328         return mnt_n + height_modifier >= 0.6;
 329 }
 330
 331
 332 bool MapgenV7::getMountainTerrainFromMap(int idx_xyz, int idx_xz, int y) {
 333         float mounthn = noise_mount_height->result[idx_xz];
 334         float height_modifier = -((float)y / rangelim(mounthn, 80.0, 150.0));
 335         return (noise_mountain->result[idx_xyz] + height_modifier >= 0.6);
 336 }
 337
 338
 339 #if 0
 340 void MapgenV7::carveRivers() {
 341         MapNode n_air(CONTENT_AIR), n_water_source(c_water_source);
 342         MapNode n_stone(c_stone);
 343         u32 index = 0;
 344
 345         int river_depth = 4;
 346
 347         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 348         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
 349                 float terrain_mod  = noise_terrain_mod->result[index];
 350                 NoiseParams *np = noise_terrain_river->np;
 351                 np->persist = noise_terrain_persist->result[index];
 352                 float terrain_river = NoisePerlin2DNoTxfm(np, x, z, seed);
 353                 float height = terrain_river * (1 - abs(terrain_mod)) *
 354                                                 noise_terrain_river->np->scale;
 355                 height = log(height * height); //log(h^3) is pretty interesting for terrain
 356
 357                 s16 y = heightmap[index];
 358                 if (height < 1.0 && y > river_depth &&
 359                         y - river_depth >= node_min.Y && y <= node_max.Y) {
 360
 361                         for (s16 ry = y; ry != y - river_depth; ry--) {
 362                                 u32 vi = vm->m_area.index(x, ry, z);
 363                                 vm->m_data[vi] = n_air;
 364                         }
 365
 366                         u32 vi = vm->m_area.index(x, y - river_depth, z);
 367                         vm->m_data[vi] = n_water_source;
 368                 }
 369         }
 370 }
 371 #endif
 372
 373
 374 int MapgenV7::generateTerrain() {
 375         int ymax = generateBaseTerrain();
 376
 377         if (flags & MGV7_MOUNTAINS)
 378                 generateMountainTerrain();
 379
 380         if (flags & MGV7_RIDGES)
 381                 generateRidgeTerrain();
 382
 383         return ymax;
 384 }
 385
 386
 387 int MapgenV7::generateBaseTerrain() {
 388         MapNode n_air(CONTENT_AIR);
 389         MapNode n_stone(c_stone);
 390         MapNode n_water(c_water_source);
 391
 392         int stone_surface_max_y = -MAP_GENERATION_LIMIT;
 393         v3s16 em = vm->m_area.getExtent();
 394         u32 index = 0;
 395
 396         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 397         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
 398                 float surface_height = baseTerrainLevelFromMap(index);
 399                 s16 surface_y = (s16)surface_height;
 400
 401                 heightmap[index]       = surface_y;
 402                 ridge_heightmap[index] = surface_y;
 403
 404                 if (surface_y > stone_surface_max_y)
 405                         stone_surface_max_y = surface_y;
 406
 407                 u32 i = vm->m_area.index(x, node_min.Y, z);
 408                 for (s16 y = node_min.Y; y <= node_max.Y; y++) {
 409                         if (vm->m_data[i].getContent() == CONTENT_IGNORE) {
 410                                 if (y <= surface_y)
 411                                         vm->m_data[i] = n_stone;
 412                                 else if (y <= water_level)
 413                                         vm->m_data[i] = n_water;
 414                                 else
 415                                         vm->m_data[i] = n_air;
 416                         }
 417                         vm->m_area.add_y(em, i, 1);
 418                 }
 419         }
 420
 421         return stone_surface_max_y;
 422 }
 423
 424
 425 void MapgenV7::generateMountainTerrain() {
 426         if (node_max.Y <= water_level)
 427                 return;
 428
 429         MapNode n_stone(c_stone);
 430         u32 index = 0;
 431
 432         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 433         for (s16 y = node_min.Y; y <= node_max.Y; y++) {
 434                 u32 vi = vm->m_area.index(node_min.X, y, z);
 435                 for (s16 x = node_min.X; x <= node_max.X; x++) {
 436                         int j = (z - node_min.Z) * csize.X + (x - node_min.X);
 437
 438                         if (getMountainTerrainFromMap(index, j, y))
 439                                 vm->m_data[vi] = n_stone;
 440
 441                         vi++;
 442                         index++;
 443                 }
 444         }
 445 }
 446
 447
 448 void MapgenV7::generateRidgeTerrain() {
 449         MapNode n_water(c_water_source);
 450         MapNode n_air(CONTENT_AIR);
 451         u32 index = 0;
 452
 453         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 454         for (s16 y = node_min.Y; y <= node_max.Y; y++) {
 455                 u32 vi = vm->m_area.index(node_min.X, y, z);
 456                 for (s16 x = node_min.X; x <= node_max.X; x++, index++, vi++) {
 457                         int j = (z - node_min.Z) * csize.X + (x - node_min.X);
 458
 459                         if (heightmap[j] < water_level - 4)
 460                                 continue;
 461
 462                         float widthn = (noise_terrain_persist->result[j] - 0.6) / 0.1;
 463                         //widthn = rangelim(widthn, -0.05, 0.5);
 464
 465                         float width = 0.3; // TODO: figure out acceptable perlin noise values
 466                         float uwatern = noise_ridge_uwater->result[j] * 2;
 467                         if (uwatern < -width || uwatern > width)
 468                                 continue;
 469
 470                         float height_mod = (float)(y + 17) / 2.5;
 471                         float width_mod  = (width - fabs(uwatern));
 472                         float nridge = noise_ridge->result[index] * (float)y / 7.0;
 473
 474                         if (y < water_level)
 475                                 nridge = -fabs(nridge) * 3.0 * widthn * 0.3;
 476
 477                         if (nridge + width_mod * height_mod < 0.6)
 478                                 continue;
 479
 480                         if (y < ridge_heightmap[j])
 481                                 ridge_heightmap[j] = y - 1;
 482
 483                         vm->m_data[vi] = (y > water_level) ? n_air : n_water;
 484                 }
 485         }
 486 }
 487
 488
 489 void MapgenV7::generateBiomes() {
 490         if (node_max.Y < water_level)
 491                 return;
 492
 493         MapNode n_air(CONTENT_AIR);
 494         MapNode n_stone(c_stone);
 495         MapNode n_water(c_water_source);
 496
 497         v3s16 em = vm->m_area.getExtent();
 498         u32 index = 0;
 499
 500         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 501         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
 502                 Biome *biome  = bmgr->biomes[biomemap[index]];
 503                 s16 dfiller   = biome->depth_filler + noise_filler_depth->result[index];
 504                 s16 y0_top    = biome->depth_top;
 505                 s16 y0_filler = biome->depth_filler + biome->depth_top + dfiller;
 506
 507                 s16 nplaced = 0;
 508                 u32 i = vm->m_area.index(x, node_max.Y, z);
 509
 510                 content_t c_above = vm->m_data[i + em.X].getContent();
 511                 bool have_air = c_above == CONTENT_AIR;
 512
 513                 for (s16 y = node_max.Y; y >= node_min.Y; y--) {
 514                         content_t c = vm->m_data[i].getContent();
 515
 516                         // It could be the case that the elevation is equal to the chunk
 517                         // boundary, but the chunk above has not been generated yet
 518                         if (y == node_max.Y && c_above == CONTENT_IGNORE &&
 519                                 y == heightmap[index] && c == c_stone) {
 520                                 int j = z * zstride + y * ystride + x;
 521                                 have_air = !getMountainTerrainFromMap(j, index, y);
 522                         }
 523
 524                         if (c == c_stone && have_air) {
 525                                 content_t c_below = vm->m_data[i - em.X].getContent();
 526
 527                                 if (c_below != CONTENT_AIR) {
 528                                         if (nplaced < y0_top) {
 529                                                 // A hack to prevent dirt_with_grass from being
 530                                                 // placed below water.  TODO: fix later
 531                                                 content_t c_place = ((y < water_level) &&
 532                                                                 (biome->c_top == c_dirt_with_grass)) ?
 533                                                                  c_dirt : biome->c_top;
 534
 535                                                 vm->m_data[i] = MapNode(c_place);
 536                                                 nplaced++;
 537                                         } else if (nplaced < y0_filler && nplaced >= y0_top) {
 538                                                 vm->m_data[i] = MapNode(biome->c_filler);
 539                                                 nplaced++;
 540                                         } else {
 541                                                 have_air = false;
 542                                                 nplaced  = 0;
 543                                         }
 544                                 }
 545                         } else if (c == c_water_source) {
 546                                 have_air = true;
 547                                 nplaced = 0;
 548                                 vm->m_data[i] = MapNode(biome->c_water);
 549                         } else if (c == CONTENT_AIR) {
 550                                 have_air = true;
 551                                 nplaced = 0;
 552                         }
 553
 554                         vm->m_area.add_y(em, i, -1);
 555                 }
 556         }
 557 }
 558
 559
 560 void MapgenV7::dustTopNodes() {
 561         v3s16 em = vm->m_area.getExtent();
 562         u32 index = 0;
 563
 564         if (water_level > node_max.Y)
 565                 return;
 566
 567         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 568         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
 569                 Biome *biome = bmgr->biomes[biomemap[index]];
 570
 571                 if (biome->c_dust == CONTENT_IGNORE)
 572                         continue;
 573
 574                 s16 y = node_max.Y;
 575                 u32 vi = vm->m_area.index(x, y, z);
 576                 for (; y >= node_min.Y; y--) {
 577                         if (vm->m_data[vi].getContent() != CONTENT_AIR)
 578                                 break;
 579
 580                         vm->m_area.add_y(em, vi, -1);
 581                 }
 582
 583                 content_t c = vm->m_data[vi].getContent();
 584                 if (c == biome->c_water && biome->c_dust_water != CONTENT_IGNORE) {
 585                         if (y < node_min.Y)
 586                                 continue;
 587
 588                         vm->m_data[vi] = MapNode(biome->c_dust_water);
 589                 } else if (!ndef->get(c).buildable_to && c != CONTENT_IGNORE) {
 590                         if (y == node_max.Y)
 591                                 continue;
 592
 593                         vm->m_area.add_y(em, vi, 1);
 594                         vm->m_data[vi] = MapNode(biome->c_dust);
 595                 }
 596         }
 597 }
 598
 599
 600 #if 0
 601 void MapgenV7::addTopNodes() {
 602         v3s16 em = vm->m_area.getExtent();
 603         s16 ntopnodes;
 604         u32 index = 0;
 605
 606         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 607         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
 608                 Biome *biome = bmgr->biomes[biomemap[index]];
 609
 610                 //////////////////// First, add top nodes below the ridge
 611                 s16 y = ridge_heightmap[index];
 612
 613                 // This cutoff is good enough, but not perfect.
 614                 // It will cut off potentially placed top nodes at chunk boundaries
 615                 if (y < node_min.Y)
 616                         continue;
 617                 if (y > node_max.Y) {
 618                         y = node_max.Y; // Let's see if we can still go downward anyway
 619                         u32 vi = vm->m_area.index(x, y, z);
 620                         content_t c = vm->m_data[vi].getContent();
 621                         if (ndef->get(c).walkable)
 622                                 continue;
 623                 }
 624
 625                 // N.B.  It is necessary to search downward since ridge_heightmap[i]
 626                 // might not be the actual height, just the lowest part in the chunk
 627                 // where a ridge had been carved
 628                 u32 i = vm->m_area.index(x, y, z);
 629                 for (; y >= node_min.Y; y--) {
 630                         content_t c = vm->m_data[i].getContent();
 631                         if (ndef->get(c).walkable)
 632                                 break;
 633                         vm->m_area.add_y(em, i, -1);
 634                 }
 635
 636                 if (y != node_min.Y - 1 && y >= water_level) {
 637                         ridge_heightmap[index] = y; //update ridgeheight
 638                         ntopnodes = biome->top_depth;
 639                         for (; y <= node_max.Y && ntopnodes; y++) {
 640                                 ntopnodes--;
 641                                 vm->m_data[i] = MapNode(biome->c_top);
 642                                 vm->m_area.add_y(em, i, 1);
 643                         }
 644                         // If dirt, grow grass on it.
 645                         if (y > water_level - 10 &&
 646                                 vm->m_data[i].getContent() == CONTENT_AIR) {
 647                                 vm->m_area.add_y(em, i, -1);
 648                                 if (vm->m_data[i].getContent() == c_dirt)
 649                                         vm->m_data[i] = MapNode(c_dirt_with_grass);
 650                         }
 651                 }
 652
 653                 //////////////////// Now, add top nodes on top of the ridge
 654                 y = heightmap[index];
 655                 if (y > node_max.Y) {
 656                         y = node_max.Y; // Let's see if we can still go downward anyway
 657                         u32 vi = vm->m_area.index(x, y, z);
 658                         content_t c = vm->m_data[vi].getContent();
 659                         if (ndef->get(c).walkable)
 660                                 continue;
 661                 }
 662
 663                 i = vm->m_area.index(x, y, z);
 664                 for (; y >= node_min.Y; y--) {
 665                         content_t c = vm->m_data[i].getContent();
 666                         if (ndef->get(c).walkable)
 667                                 break;
 668                         vm->m_area.add_y(em, i, -1);
 669                 }
 670
 671                 if (y != node_min.Y - 1) {
 672                         ntopnodes = biome->top_depth;
 673                         // Let's see if we've already added it...
 674                         if (y == ridge_heightmap[index] + ntopnodes - 1)
 675                                 continue;
 676
 677                         for (; y <= node_max.Y && ntopnodes; y++) {
 678                                 ntopnodes--;
 679                                 vm->m_data[i] = MapNode(biome->c_top);
 680                                 vm->m_area.add_y(em, i, 1);
 681                         }
 682                         // If dirt, grow grass on it.
 683                         if (y > water_level - 10 &&
 684                                 vm->m_data[i].getContent() == CONTENT_AIR) {
 685                                 vm->m_area.add_y(em, i, -1);
 686                                 if (vm->m_data[i].getContent() == c_dirt)
 687                                         vm->m_data[i] = MapNode(c_dirt_with_grass);
 688                         }
 689                 }
 690         }
 691 }
 692 #endif
 693
 694
 695 #include "mapgen_v6.h"
 696 void MapgenV7::generateCaves(int max_stone_y) {
 697         PseudoRandom ps(blockseed + 21343);
 698
 699         int volume_nodes = (node_max.X - node_min.X + 1) *
 700                                            (node_max.Y - node_min.Y + 1) *
 701                                            (node_max.Z - node_min.Z + 1);
 702         float cave_amount = NoisePerlin2D(&nparams_v6_def_cave,
 703                                                                 node_min.X, node_min.Y, seed);
 704
 705         u32 caves_count = MYMAX(0.0, cave_amount) * volume_nodes / 250000;
 706         for (u32 i = 0; i < caves_count; i++) {
 707                 CaveV7 cave(this, &ps, false);
 708                 cave.makeCave(node_min, node_max, max_stone_y);
 709         }
 710
 711         u32 bruises_count = (ps.range(1, 8) == 1) ? ps.range(0, ps.range(0, 2)) : 1;
 712         for (u32 i = 0; i < bruises_count; i++) {
 713                 CaveV7 cave(this, &ps, true);
 714                 cave.makeCave(node_min, node_max, max_stone_y);
 715         }
 716 }