src/mapgen/mapgen_v7.cpp

   1 /*
   2 Minetest
   3 Copyright (C) 2014-2020 paramat
   4 Copyright (C) 2013-2016 kwolekr, Ryan Kwolek <kwolekr@minetest.net>
   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 <cmath>
  24 #include "voxel.h"
  25 #include "noise.h"
  26 #include "mapblock.h"
  27 #include "mapnode.h"
  28 #include "map.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 "mg_biome.h"
  37 #include "mg_ore.h"
  38 #include "mg_decoration.h"
  39 #include "mapgen_v7.h"
  40
  41
  42 FlagDesc flagdesc_mapgen_v7[] = {
  43         {"mountains",   MGV7_MOUNTAINS},
  44         {"ridges",      MGV7_RIDGES},
  45         {"floatlands",  MGV7_FLOATLANDS},
  46         {"caverns",     MGV7_CAVERNS},
  47         {NULL,          0}
  48 };
  49
  50
  51 ////////////////////////////////////////////////////////////////////////////////
  52
  53
  54 MapgenV7::MapgenV7(MapgenV7Params *params, EmergeParams *emerge)
  55         : MapgenBasic(MAPGEN_V7, params, emerge)
  56 {
  57         spflags            = params->spflags;
  58         mount_zero_level   = params->mount_zero_level;
  59         floatland_ymin     = params->floatland_ymin;
  60         floatland_ymax     = params->floatland_ymax;
  61         floatland_taper    = params->floatland_taper;
  62         float_taper_exp    = params->float_taper_exp;
  63         floatland_density  = params->floatland_density;
  64         floatland_ywater   = params->floatland_ywater;
  65
  66         cave_width         = params->cave_width;
  67         large_cave_depth   = params->large_cave_depth;
  68         small_cave_num_min = params->small_cave_num_min;
  69         small_cave_num_max = params->small_cave_num_max;
  70         large_cave_num_min = params->large_cave_num_min;
  71         large_cave_num_max = params->large_cave_num_max;
  72         large_cave_flooded = params->large_cave_flooded;
  73         cavern_limit       = params->cavern_limit;
  74         cavern_taper       = params->cavern_taper;
  75         cavern_threshold   = params->cavern_threshold;
  76         dungeon_ymin       = params->dungeon_ymin;
  77         dungeon_ymax       = params->dungeon_ymax;
  78
  79         // Allocate floatland noise offset cache
  80         this->float_offset_cache = new float[csize.Y + 2];
  81
  82         // 2D noise
  83         noise_terrain_base =
  84                 new Noise(&params->np_terrain_base,    seed, csize.X, csize.Z);
  85         noise_terrain_alt =
  86                 new Noise(&params->np_terrain_alt,     seed, csize.X, csize.Z);
  87         noise_terrain_persist =
  88                 new Noise(&params->np_terrain_persist, seed, csize.X, csize.Z);
  89         noise_height_select =
  90                 new Noise(&params->np_height_select,   seed, csize.X, csize.Z);
  91         noise_filler_depth =
  92                 new Noise(&params->np_filler_depth,    seed, csize.X, csize.Z);
  93
  94         if (spflags & MGV7_MOUNTAINS) {
  95                 // 2D noise
  96                 noise_mount_height =
  97                         new Noise(&params->np_mount_height, seed, csize.X, csize.Z);
  98                 // 3D noise, 1 up, 1 down overgeneration
  99                 noise_mountain =
 100                         new Noise(&params->np_mountain,     seed, csize.X, csize.Y + 2, csize.Z);
 101         }
 102
 103         if (spflags & MGV7_RIDGES) {
 104                 // 2D noise
 105                 noise_ridge_uwater =
 106                         new Noise(&params->np_ridge_uwater, seed, csize.X, csize.Z);
 107                 // 3D noise, 1 up, 1 down overgeneration
 108                 noise_ridge =
 109                         new Noise(&params->np_ridge,        seed, csize.X, csize.Y + 2, csize.Z);
 110         }
 111
 112         if (spflags & MGV7_FLOATLANDS) {
 113                 // 3D noise, 1 up, 1 down overgeneration
 114                 noise_floatland =
 115                         new Noise(&params->np_floatland,    seed, csize.X, csize.Y + 2, csize.Z);
 116         }
 117
 118         // 3D noise, 1 down overgeneration
 119         MapgenBasic::np_cave1    = params->np_cave1;
 120         MapgenBasic::np_cave2    = params->np_cave2;
 121         MapgenBasic::np_cavern   = params->np_cavern;
 122         // 3D noise
 123         MapgenBasic::np_dungeons = params->np_dungeons;
 124 }
 125
 126
 127 MapgenV7::~MapgenV7()
 128 {
 129         delete noise_terrain_base;
 130         delete noise_terrain_alt;
 131         delete noise_terrain_persist;
 132         delete noise_height_select;
 133         delete noise_filler_depth;
 134
 135         if (spflags & MGV7_MOUNTAINS) {
 136                 delete noise_mount_height;
 137                 delete noise_mountain;
 138         }
 139
 140         if (spflags & MGV7_RIDGES) {
 141                 delete noise_ridge_uwater;
 142                 delete noise_ridge;
 143         }
 144
 145         if (spflags & MGV7_FLOATLANDS) {
 146                 delete noise_floatland;
 147         }
 148
 149         delete []float_offset_cache;
 150 }
 151
 152
 153 MapgenV7Params::MapgenV7Params():
 154         np_terrain_base      (4.0,   70.0,  v3f(600,  600,  600),  82341, 5, 0.6,  2.0),
 155         np_terrain_alt       (4.0,   25.0,  v3f(600,  600,  600),  5934,  5, 0.6,  2.0),
 156         np_terrain_persist   (0.6,   0.1,   v3f(2000, 2000, 2000), 539,   3, 0.6,  2.0),
 157         np_height_select     (-8.0,  16.0,  v3f(500,  500,  500),  4213,  6, 0.7,  2.0),
 158         np_filler_depth      (0.0,   1.2,   v3f(150,  150,  150),  261,   3, 0.7,  2.0),
 159         np_mount_height      (256.0, 112.0, v3f(1000, 1000, 1000), 72449, 3, 0.6,  2.0),
 160         np_ridge_uwater      (0.0,   1.0,   v3f(1000, 1000, 1000), 85039, 5, 0.6,  2.0),
 161         np_mountain          (-0.6,  1.0,   v3f(250,  350,  250),  5333,  5, 0.63, 2.0),
 162         np_ridge             (0.0,   1.0,   v3f(100,  100,  100),  6467,  4, 0.75, 2.0),
 163         np_floatland         (0.0,   0.7,   v3f(384,  96,   384),  1009,  4, 0.75, 1.618),
 164         np_cavern            (0.0,   1.0,   v3f(384,  128,  384),  723,   5, 0.63, 2.0),
 165         np_cave1             (0.0,   12.0,  v3f(61,   61,   61),   52534, 3, 0.5,  2.0),
 166         np_cave2             (0.0,   12.0,  v3f(67,   67,   67),   10325, 3, 0.5,  2.0),
 167         np_dungeons          (0.9,   0.5,   v3f(500,  500,  500),  0,     2, 0.8,  2.0)
 168 {
 169 }
 170
 171
 172 void MapgenV7Params::readParams(const Settings *settings)
 173 {
 174         settings->getFlagStrNoEx("mgv7_spflags", spflags, flagdesc_mapgen_v7);
 175         settings->getS16NoEx("mgv7_mount_zero_level",       mount_zero_level);
 176         settings->getS16NoEx("mgv7_floatland_ymin",         floatland_ymin);
 177         settings->getS16NoEx("mgv7_floatland_ymax",         floatland_ymax);
 178         settings->getS16NoEx("mgv7_floatland_taper",        floatland_taper);
 179         settings->getFloatNoEx("mgv7_float_taper_exp",      float_taper_exp);
 180         settings->getFloatNoEx("mgv7_floatland_density",    floatland_density);
 181         settings->getS16NoEx("mgv7_floatland_ywater",       floatland_ywater);
 182
 183         settings->getFloatNoEx("mgv7_cave_width",           cave_width);
 184         settings->getS16NoEx("mgv7_large_cave_depth",       large_cave_depth);
 185         settings->getU16NoEx("mgv7_small_cave_num_min",     small_cave_num_min);
 186         settings->getU16NoEx("mgv7_small_cave_num_max",     small_cave_num_max);
 187         settings->getU16NoEx("mgv7_large_cave_num_min",     large_cave_num_min);
 188         settings->getU16NoEx("mgv7_large_cave_num_max",     large_cave_num_max);
 189         settings->getFloatNoEx("mgv7_large_cave_flooded",   large_cave_flooded);
 190         settings->getS16NoEx("mgv7_cavern_limit",           cavern_limit);
 191         settings->getS16NoEx("mgv7_cavern_taper",           cavern_taper);
 192         settings->getFloatNoEx("mgv7_cavern_threshold",     cavern_threshold);
 193         settings->getS16NoEx("mgv7_dungeon_ymin",           dungeon_ymin);
 194         settings->getS16NoEx("mgv7_dungeon_ymax",           dungeon_ymax);
 195
 196         settings->getNoiseParams("mgv7_np_terrain_base",    np_terrain_base);
 197         settings->getNoiseParams("mgv7_np_terrain_alt",     np_terrain_alt);
 198         settings->getNoiseParams("mgv7_np_terrain_persist", np_terrain_persist);
 199         settings->getNoiseParams("mgv7_np_height_select",   np_height_select);
 200         settings->getNoiseParams("mgv7_np_filler_depth",    np_filler_depth);
 201         settings->getNoiseParams("mgv7_np_mount_height",    np_mount_height);
 202         settings->getNoiseParams("mgv7_np_ridge_uwater",    np_ridge_uwater);
 203         settings->getNoiseParams("mgv7_np_mountain",        np_mountain);
 204         settings->getNoiseParams("mgv7_np_ridge",           np_ridge);
 205         settings->getNoiseParams("mgv7_np_floatland",       np_floatland);
 206         settings->getNoiseParams("mgv7_np_cavern",          np_cavern);
 207         settings->getNoiseParams("mgv7_np_cave1",           np_cave1);
 208         settings->getNoiseParams("mgv7_np_cave2",           np_cave2);
 209         settings->getNoiseParams("mgv7_np_dungeons",        np_dungeons);
 210 }
 211
 212
 213 void MapgenV7Params::writeParams(Settings *settings) const
 214 {
 215         settings->setFlagStr("mgv7_spflags", spflags, flagdesc_mapgen_v7);
 216         settings->setS16("mgv7_mount_zero_level",           mount_zero_level);
 217         settings->setS16("mgv7_floatland_ymin",             floatland_ymin);
 218         settings->setS16("mgv7_floatland_ymax",             floatland_ymax);
 219         settings->setS16("mgv7_floatland_taper",            floatland_taper);
 220         settings->setFloat("mgv7_float_taper_exp",          float_taper_exp);
 221         settings->setFloat("mgv7_floatland_density",        floatland_density);
 222         settings->setS16("mgv7_floatland_ywater",           floatland_ywater);
 223
 224         settings->setFloat("mgv7_cave_width",               cave_width);
 225         settings->setS16("mgv7_large_cave_depth",           large_cave_depth);
 226         settings->setU16("mgv7_small_cave_num_min",         small_cave_num_min);
 227         settings->setU16("mgv7_small_cave_num_max",         small_cave_num_max);
 228         settings->setU16("mgv7_large_cave_num_min",         large_cave_num_min);
 229         settings->setU16("mgv7_large_cave_num_max",         large_cave_num_max);
 230         settings->setFloat("mgv7_large_cave_flooded",       large_cave_flooded);
 231         settings->setS16("mgv7_cavern_limit",               cavern_limit);
 232         settings->setS16("mgv7_cavern_taper",               cavern_taper);
 233         settings->setFloat("mgv7_cavern_threshold",         cavern_threshold);
 234         settings->setS16("mgv7_dungeon_ymin",               dungeon_ymin);
 235         settings->setS16("mgv7_dungeon_ymax",               dungeon_ymax);
 236
 237         settings->setNoiseParams("mgv7_np_terrain_base",    np_terrain_base);
 238         settings->setNoiseParams("mgv7_np_terrain_alt",     np_terrain_alt);
 239         settings->setNoiseParams("mgv7_np_terrain_persist", np_terrain_persist);
 240         settings->setNoiseParams("mgv7_np_height_select",   np_height_select);
 241         settings->setNoiseParams("mgv7_np_filler_depth",    np_filler_depth);
 242         settings->setNoiseParams("mgv7_np_mount_height",    np_mount_height);
 243         settings->setNoiseParams("mgv7_np_ridge_uwater",    np_ridge_uwater);
 244         settings->setNoiseParams("mgv7_np_mountain",        np_mountain);
 245         settings->setNoiseParams("mgv7_np_ridge",           np_ridge);
 246         settings->setNoiseParams("mgv7_np_floatland",       np_floatland);
 247         settings->setNoiseParams("mgv7_np_cavern",          np_cavern);
 248         settings->setNoiseParams("mgv7_np_cave1",           np_cave1);
 249         settings->setNoiseParams("mgv7_np_cave2",           np_cave2);
 250         settings->setNoiseParams("mgv7_np_dungeons",        np_dungeons);
 251 }
 252
 253
 254 void MapgenV7Params::setDefaultSettings(Settings *settings)
 255 {
 256         settings->setDefault("mgv7_spflags", flagdesc_mapgen_v7,
 257                 MGV7_MOUNTAINS | MGV7_RIDGES | MGV7_CAVERNS);
 258 }
 259
 260
 261 ////////////////////////////////////////////////////////////////////////////////
 262
 263
 264 int MapgenV7::getSpawnLevelAtPoint(v2s16 p)
 265 {
 266         // If rivers are enabled, first check if in a river
 267         if (spflags & MGV7_RIDGES) {
 268                 float width = 0.2f;
 269                 float uwatern = NoisePerlin2D(&noise_ridge_uwater->np, p.X, p.Y, seed) *
 270                         2.0f;
 271                 if (std::fabs(uwatern) <= width)
 272                         return MAX_MAP_GENERATION_LIMIT; // Unsuitable spawn point
 273         }
 274
 275         // Terrain noise 'offset' is the average level of that terrain.
 276         // At least 50% of terrain will be below the higher of base and alt terrain
 277         // 'offset's.
 278         // Raising the maximum spawn level above 'water_level + 16' is necessary
 279         // for when terrain 'offset's are set much higher than water_level.
 280         s16 max_spawn_y = std::fmax(std::fmax(noise_terrain_alt->np.offset,
 281                         noise_terrain_base->np.offset),
 282                         water_level + 16);
 283         // Base terrain calculation
 284         s16 y = baseTerrainLevelAtPoint(p.X, p.Y);
 285
 286         // If mountains are disabled, terrain level is base terrain level.
 287         // Avoids mid-air spawn where mountain terrain would have been.
 288         if (!(spflags & MGV7_MOUNTAINS)) {
 289                 if (y < water_level || y > max_spawn_y)
 290                         return MAX_MAP_GENERATION_LIMIT; // Unsuitable spawn point
 291
 292                 // y + 2 because y is surface level and due to biome 'dust'
 293                 return y + 2;
 294         }
 295
 296         // Search upwards for first node without mountain terrain
 297         int iters = 256;
 298         while (iters > 0 && y <= max_spawn_y) {
 299                 if (!getMountainTerrainAtPoint(p.X, y + 1, p.Y)) {
 300                         if (y <= water_level || y > max_spawn_y)
 301                                 return MAX_MAP_GENERATION_LIMIT; // Unsuitable spawn point
 302
 303                         // y + 1 due to biome 'dust'
 304                         return y + 1;
 305                 }
 306                 y++;
 307                 iters--;
 308         }
 309
 310         // Unsuitable spawn point
 311         return MAX_MAP_GENERATION_LIMIT;
 312 }
 313
 314
 315 void MapgenV7::makeChunk(BlockMakeData *data)
 316 {
 317         // Pre-conditions
 318         assert(data->vmanip);
 319         assert(data->nodedef);
 320         assert(data->blockpos_requested.X >= data->blockpos_min.X &&
 321                 data->blockpos_requested.Y >= data->blockpos_min.Y &&
 322                 data->blockpos_requested.Z >= data->blockpos_min.Z);
 323         assert(data->blockpos_requested.X <= data->blockpos_max.X &&
 324                 data->blockpos_requested.Y <= data->blockpos_max.Y &&
 325                 data->blockpos_requested.Z <= data->blockpos_max.Z);
 326
 327         //TimeTaker t("makeChunk");
 328
 329         this->generating = true;
 330         this->vm = data->vmanip;
 331         this->ndef = data->nodedef;
 332
 333         v3s16 blockpos_min = data->blockpos_min;
 334         v3s16 blockpos_max = data->blockpos_max;
 335         node_min = blockpos_min * MAP_BLOCKSIZE;
 336         node_max = (blockpos_max + v3s16(1, 1, 1)) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
 337         full_node_min = (blockpos_min - 1) * MAP_BLOCKSIZE;
 338         full_node_max = (blockpos_max + 2) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
 339
 340         blockseed = getBlockSeed2(full_node_min, seed);
 341
 342         // Generate base and mountain terrain
 343         s16 stone_surface_max_y = generateTerrain();
 344
 345         // Generate rivers
 346         if (spflags & MGV7_RIDGES)
 347                 generateRidgeTerrain();
 348
 349         // Create heightmap
 350         updateHeightmap(node_min, node_max);
 351
 352         // Init biome generator, place biome-specific nodes, and build biomemap
 353         if (flags & MG_BIOMES) {
 354                 biomegen->calcBiomeNoise(node_min);
 355                 generateBiomes();
 356         }
 357
 358         // Generate tunnels, caverns and large randomwalk caves
 359         if (flags & MG_CAVES) {
 360                 // Generate tunnels first as caverns confuse them
 361                 generateCavesNoiseIntersection(stone_surface_max_y);
 362
 363                 // Generate caverns
 364                 bool near_cavern = false;
 365                 if (spflags & MGV7_CAVERNS)
 366                         near_cavern = generateCavernsNoise(stone_surface_max_y);
 367
 368                 // Generate large randomwalk caves
 369                 if (near_cavern)
 370                         // Disable large randomwalk caves in this mapchunk by setting
 371                         // 'large cave depth' to world base. Avoids excessive liquid in
 372                         // large caverns and floating blobs of overgenerated liquid.
 373                         generateCavesRandomWalk(stone_surface_max_y,
 374                                 -MAX_MAP_GENERATION_LIMIT);
 375                 else
 376                         generateCavesRandomWalk(stone_surface_max_y, large_cave_depth);
 377         }
 378
 379         // Generate the registered ores
 380         m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max);
 381
 382         // Generate dungeons
 383         if (flags & MG_DUNGEONS)
 384                 generateDungeons(stone_surface_max_y);
 385
 386         // Generate the registered decorations
 387         if (flags & MG_DECORATIONS)
 388                 m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
 389
 390         // Sprinkle some dust on top after everything else was generated
 391         if (flags & MG_BIOMES)
 392                 dustTopNodes();
 393
 394         // Update liquids
 395         updateLiquid(&data->transforming_liquid, full_node_min, full_node_max);
 396
 397         // Calculate lighting
 398         // Limit floatland shadows
 399         bool propagate_shadow = !((spflags & MGV7_FLOATLANDS) &&
 400                 node_max.Y >= floatland_ymin - csize.Y * 2 && node_min.Y <= floatland_ymax);
 401
 402         if (flags & MG_LIGHT)
 403                 calcLighting(node_min - v3s16(0, 1, 0), node_max + v3s16(0, 1, 0),
 404                         full_node_min, full_node_max, propagate_shadow);
 405
 406         this->generating = false;
 407
 408         //printf("makeChunk: %lums\n", t.stop());
 409 }
 410
 411
 412 ////////////////////////////////////////////////////////////////////////////////
 413
 414
 415 float MapgenV7::baseTerrainLevelAtPoint(s16 x, s16 z)
 416 {
 417         float hselect = NoisePerlin2D(&noise_height_select->np, x, z, seed);
 418         hselect = rangelim(hselect, 0.0f, 1.0f);
 419
 420         float persist = NoisePerlin2D(&noise_terrain_persist->np, x, z, seed);
 421
 422         noise_terrain_base->np.persist = persist;
 423         float height_base = NoisePerlin2D(&noise_terrain_base->np, x, z, seed);
 424
 425         noise_terrain_alt->np.persist = persist;
 426         float height_alt = NoisePerlin2D(&noise_terrain_alt->np, x, z, seed);
 427
 428         if (height_alt > height_base)
 429                 return height_alt;
 430
 431         return (height_base * hselect) + (height_alt * (1.0f - hselect));
 432 }
 433
 434
 435 float MapgenV7::baseTerrainLevelFromMap(int index)
 436 {
 437         float hselect = rangelim(noise_height_select->result[index], 0.0f, 1.0f);
 438         float height_base = noise_terrain_base->result[index];
 439         float height_alt = noise_terrain_alt->result[index];
 440
 441         if (height_alt > height_base)
 442                 return height_alt;
 443
 444         return (height_base * hselect) + (height_alt * (1.0f - hselect));
 445 }
 446
 447
 448 bool MapgenV7::getMountainTerrainAtPoint(s16 x, s16 y, s16 z)
 449 {
 450         float mnt_h_n =
 451                 std::fmax(NoisePerlin2D(&noise_mount_height->np, x, z, seed), 1.0f);
 452         float density_gradient = -((float)(y - mount_zero_level) / mnt_h_n);
 453         float mnt_n = NoisePerlin3D(&noise_mountain->np, x, y, z, seed);
 454
 455         return mnt_n + density_gradient >= 0.0f;
 456 }
 457
 458
 459 bool MapgenV7::getMountainTerrainFromMap(int idx_xyz, int idx_xz, s16 y)
 460 {
 461         float mounthn = std::fmax(noise_mount_height->result[idx_xz], 1.0f);
 462         float density_gradient = -((float)(y - mount_zero_level) / mounthn);
 463         float mountn = noise_mountain->result[idx_xyz];
 464
 465         return mountn + density_gradient >= 0.0f;
 466 }
 467
 468
 469 bool MapgenV7::getFloatlandTerrainFromMap(int idx_xyz, float float_offset)
 470 {
 471         return noise_floatland->result[idx_xyz] + floatland_density - float_offset >= 0.0f;
 472 }
 473
 474
 475 int MapgenV7::generateTerrain()
 476 {
 477         MapNode n_air(CONTENT_AIR);
 478         MapNode n_stone(c_stone);
 479         MapNode n_water(c_water_source);
 480
 481         //// Calculate noise for terrain generation
 482         noise_terrain_persist->perlinMap2D(node_min.X, node_min.Z);
 483         float *persistmap = noise_terrain_persist->result;
 484
 485         noise_terrain_base->perlinMap2D(node_min.X, node_min.Z, persistmap);
 486         noise_terrain_alt->perlinMap2D(node_min.X, node_min.Z, persistmap);
 487         noise_height_select->perlinMap2D(node_min.X, node_min.Z);
 488
 489         if (spflags & MGV7_MOUNTAINS) {
 490                 noise_mount_height->perlinMap2D(node_min.X, node_min.Z);
 491                 noise_mountain->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
 492         }
 493
 494         //// Floatlands
 495         // 'Generate floatlands in this mapchunk' bool for
 496         // simplification of condition checks in y-loop.
 497         bool gen_floatlands = false;
 498         u8 cache_index = 0;
 499         // Y values where floatland tapering starts
 500         s16 float_taper_ymax = floatland_ymax - floatland_taper;
 501         s16 float_taper_ymin = floatland_ymin + floatland_taper;
 502
 503         if ((spflags & MGV7_FLOATLANDS) &&
 504                         node_max.Y >= floatland_ymin && node_min.Y <= floatland_ymax) {
 505                 gen_floatlands = true;
 506                 // Calculate noise for floatland generation
 507                 noise_floatland->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
 508
 509                 // Cache floatland noise offset values, for floatland tapering
 510                 for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++, cache_index++) {
 511                         float float_offset = 0.0f;
 512                         if (y > float_taper_ymax) {
 513                                 float_offset = std::pow((y - float_taper_ymax) / (float)floatland_taper,
 514                                         float_taper_exp) * 4.0f;
 515                         } else if (y < float_taper_ymin) {
 516                                 float_offset = std::pow((float_taper_ymin - y) / (float)floatland_taper,
 517                                         float_taper_exp) * 4.0f;
 518                         }
 519                         float_offset_cache[cache_index] = float_offset;
 520                 }
 521         }
 522
 523         //// Place nodes
 524         const v3s16 &em = vm->m_area.getExtent();
 525         s16 stone_surface_max_y = -MAX_MAP_GENERATION_LIMIT;
 526         u32 index2d = 0;
 527
 528         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 529         for (s16 x = node_min.X; x <= node_max.X; x++, index2d++) {
 530                 s16 surface_y = baseTerrainLevelFromMap(index2d);
 531                 if (surface_y > stone_surface_max_y)
 532                         stone_surface_max_y = surface_y;
 533
 534                 cache_index = 0;
 535                 u32 vi = vm->m_area.index(x, node_min.Y - 1, z);
 536                 u32 index3d = (z - node_min.Z) * zstride_1u1d + (x - node_min.X);
 537
 538                 for (s16 y = node_min.Y - 1; y <= node_max.Y + 1;
 539                                 y++,
 540                                 index3d += ystride,
 541                                 VoxelArea::add_y(em, vi, 1),
 542                                 cache_index++) {
 543                         if (vm->m_data[vi].getContent() != CONTENT_IGNORE)
 544                                 continue;
 545
 546                         if (y <= surface_y) {
 547                                 vm->m_data[vi] = n_stone; // Base terrain
 548                         } else if ((spflags & MGV7_MOUNTAINS) &&
 549                                         getMountainTerrainFromMap(index3d, index2d, y)) {
 550                                 vm->m_data[vi] = n_stone; // Mountain terrain
 551                                 if (y > stone_surface_max_y)
 552                                         stone_surface_max_y = y;
 553                         } else if (gen_floatlands &&
 554                                         getFloatlandTerrainFromMap(index3d,
 555                                         float_offset_cache[cache_index])) {
 556                                 vm->m_data[vi] = n_stone; // Floatland terrain
 557                                 if (y > stone_surface_max_y)
 558                                         stone_surface_max_y = y;
 559                         } else if (y <= water_level) { // Surface water
 560                                 vm->m_data[vi] = n_water;
 561                         } else if (gen_floatlands && y >= float_taper_ymax && y <= floatland_ywater) {
 562                                 vm->m_data[vi] = n_water; // Water for solid floatland layer only
 563                         } else {
 564                                 vm->m_data[vi] = n_air; // Air
 565                         }
 566                 }
 567         }
 568
 569         return stone_surface_max_y;
 570 }
 571
 572
 573 void MapgenV7::generateRidgeTerrain()
 574 {
 575         if (node_max.Y < water_level - 16 ||
 576                         (node_max.Y >= floatland_ymin && node_min.Y <= floatland_ymax))
 577                 return;
 578
 579         noise_ridge->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
 580         noise_ridge_uwater->perlinMap2D(node_min.X, node_min.Z);
 581
 582         MapNode n_water(c_water_source);
 583         MapNode n_air(CONTENT_AIR);
 584         u32 index3d = 0;
 585         float width = 0.2f;
 586
 587         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 588         for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
 589                 u32 vi = vm->m_area.index(node_min.X, y, z);
 590                 for (s16 x = node_min.X; x <= node_max.X; x++, index3d++, vi++) {
 591                         u32 index2d = (z - node_min.Z) * csize.X + (x - node_min.X);
 592                         float uwatern = noise_ridge_uwater->result[index2d] * 2.0f;
 593                         if (std::fabs(uwatern) > width)
 594                                 continue;
 595                         // Optimises, but also avoids removing nodes placed by mods in
 596                         // 'on-generated', when generating outside mapchunk.
 597                         content_t c = vm->m_data[vi].getContent();
 598                         if (c != c_stone)
 599                                 continue;
 600
 601                         float altitude = y - water_level;
 602                         float height_mod = (altitude + 17.0f) / 2.5f;
 603                         float width_mod = width - std::fabs(uwatern);
 604                         float nridge = noise_ridge->result[index3d] *
 605                                 std::fmax(altitude, 0.0f) / 7.0f;
 606                         if (nridge + width_mod * height_mod < 0.6f)
 607                                 continue;
 608
 609                         vm->m_data[vi] = (y > water_level) ? n_air : n_water;
 610                 }
 611         }
 612 }