src/mapgen_valleys.cpp

   1 /*
   2 Minetest Valleys C
   3 Copyright (C) 2010-2015 kwolekr, Ryan Kwolek <kwolekr@minetest.net>
   4 Copyright (C) 2010-2015 paramat, Matt Gregory
   5 Copyright (C) 2016 Duane Robertson <duane@duanerobertson.com>
   6
   7 Based on Valleys Mapgen by Gael de Sailly
   8  (https://forum.minetest.net/viewtopic.php?f=9&t=11430)
   9 and mapgen_v7, mapgen_flat by kwolekr and paramat.
  10
  11 Licensing changed by permission of Gael de Sailly.
  12
  13 This program is free software; you can redistribute it and/or modify
  14 it under the terms of the GNU Lesser General Public License as published by
  15 the Free Software Foundation; either version 2.1 of the License, or
  16 (at your option) any later version.
  17
  18 This program is distributed in the hope that it will be useful,
  19 but WITHOUT ANY WARRANTY; without even the implied warranty of
  20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21 GNU Lesser General Public License for more details.
  22
  23 You should have received a copy of the GNU Lesser General Public License along
  24 with this program; if not, write to the Free Software Foundation, Inc.,
  25 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  26 */
  27
  28 #include "mapgen.h"
  29 #include "voxel.h"
  30 #include "noise.h"
  31 #include "mapblock.h"
  32 #include "mapnode.h"
  33 #include "map.h"
  34 #include "content_sao.h"
  35 #include "nodedef.h"
  36 #include "voxelalgorithms.h"
  37 #include "settings.h" // For g_settings
  38 #include "emerge.h"
  39 #include "dungeongen.h"
  40 #include "treegen.h"
  41 #include "mg_biome.h"
  42 #include "mg_ore.h"
  43 #include "mg_decoration.h"
  44 #include "mapgen_valleys.h"
  45 #include "cavegen.h"
  46
  47
  48 //#undef NDEBUG
  49 //#include "assert.h"
  50
  51 //#include "util/timetaker.h"
  52 //#include "profiler.h"
  53
  54
  55 //static Profiler mapgen_prof;
  56 //Profiler *mapgen_profiler = &mapgen_prof;
  57
  58 static FlagDesc flagdesc_mapgen_valleys[] = {
  59         {"altitude_chill", MG_VALLEYS_ALT_CHILL},
  60         {"humid_rivers",   MG_VALLEYS_HUMID_RIVERS},
  61         {NULL,             0}
  62 };
  63
  64 ///////////////////////////////////////////////////////////////////////////////
  65
  66
  67 MapgenValleys::MapgenValleys(int mapgenid, MapgenParams *params, EmergeManager *emerge)
  68         : Mapgen(mapgenid, params, emerge)
  69 {
  70         this->m_emerge = emerge;
  71         this->bmgr = emerge->biomemgr;
  72
  73         //// amount of elements to skip for the next index
  74         //// for noise/height/biome maps (not vmanip)
  75         this->ystride = csize.X;
  76         this->zstride = csize.X * (csize.Y + 2);
  77
  78         this->biomemap  = new u8[csize.X * csize.Z];
  79         this->heightmap = new s16[csize.X * csize.Z];
  80         this->heatmap   = NULL;
  81         this->humidmap  = NULL;
  82
  83         this->map_gen_limit = MYMIN(MAX_MAP_GENERATION_LIMIT,
  84                         g_settings->getU16("map_generation_limit"));
  85
  86         MapgenValleysParams *sp = (MapgenValleysParams *)params->sparams;
  87         this->spflags = sp->spflags;
  88
  89         this->humid_rivers       = (spflags & MG_VALLEYS_HUMID_RIVERS);
  90         this->use_altitude_chill = (spflags & MG_VALLEYS_ALT_CHILL);
  91
  92         this->altitude_chill     = sp->altitude_chill;
  93         this->humidity_adjust    = params->np_biome_humidity.offset - 50.f;
  94         this->large_cave_depth   = sp->large_cave_depth;
  95         this->lava_features_lim  = rangelim(sp->lava_features, 0, 10);
  96         this->massive_cave_depth = sp->massive_cave_depth;
  97         this->river_depth_bed    = sp->river_depth + 1.f;
  98         this->river_size_factor  = sp->river_size / 100.f;
  99         this->water_features_lim = rangelim(sp->water_features, 0, 10);
 100
 101         // a small chance of overflows if the settings are very high
 102         this->cave_water_max_height = water_level + MYMAX(0, water_features_lim - 4) * 50;
 103         this->lava_max_height       = water_level + MYMAX(0, lava_features_lim - 4) * 50;
 104
 105         tcave_cache = new float[csize.Y + 2];
 106
 107         //// 2D Terrain noise
 108         noise_filler_depth       = new Noise(&sp->np_filler_depth,       seed, csize.X, csize.Z);
 109         noise_inter_valley_slope = new Noise(&sp->np_inter_valley_slope, seed, csize.X, csize.Z);
 110         noise_rivers             = new Noise(&sp->np_rivers,             seed, csize.X, csize.Z);
 111         noise_terrain_height     = new Noise(&sp->np_terrain_height,     seed, csize.X, csize.Z);
 112         noise_valley_depth       = new Noise(&sp->np_valley_depth,       seed, csize.X, csize.Z);
 113         noise_valley_profile     = new Noise(&sp->np_valley_profile,     seed, csize.X, csize.Z);
 114
 115         //// 3D Terrain noise
 116         noise_cave1             = new Noise(&sp->np_cave1,             seed, csize.X, csize.Y + 2, csize.Z);
 117         noise_cave2             = new Noise(&sp->np_cave2,             seed, csize.X, csize.Y + 2, csize.Z);
 118         noise_inter_valley_fill = new Noise(&sp->np_inter_valley_fill, seed, csize.X, csize.Y + 2, csize.Z);
 119         noise_massive_caves     = new Noise(&sp->np_massive_caves,     seed, csize.X, csize.Y + 2, csize.Z);
 120
 121         //// Biome noise
 122         noise_heat_blend     = new Noise(&params->np_biome_heat_blend,     seed, csize.X, csize.Z);
 123         noise_heat           = new Noise(&params->np_biome_heat,           seed, csize.X, csize.Z);
 124         noise_humidity_blend = new Noise(&params->np_biome_humidity_blend, seed, csize.X, csize.Z);
 125         noise_humidity       = new Noise(&params->np_biome_humidity,       seed, csize.X, csize.Z);
 126
 127         //// Resolve nodes to be used
 128         INodeDefManager *ndef = emerge->ndef;
 129
 130         c_cobble               = ndef->getId("mapgen_cobble");
 131         c_desert_stone         = ndef->getId("mapgen_desert_stone");
 132         c_dirt                 = ndef->getId("mapgen_dirt");
 133         c_lava_source          = ndef->getId("mapgen_lava_source");
 134         c_mossycobble          = ndef->getId("mapgen_mossycobble");
 135         c_river_water_source   = ndef->getId("mapgen_river_water_source");
 136         c_sand                 = ndef->getId("mapgen_sand");
 137         c_sandstonebrick       = ndef->getId("mapgen_sandstonebrick");
 138         c_sandstone            = ndef->getId("mapgen_sandstone");
 139         c_stair_cobble         = ndef->getId("mapgen_stair_cobble");
 140         c_stair_sandstonebrick = ndef->getId("mapgen_stair_sandstonebrick");
 141         c_stone                = ndef->getId("mapgen_stone");
 142         c_water_source         = ndef->getId("mapgen_water_source");
 143
 144         if (c_mossycobble == CONTENT_IGNORE)
 145                 c_mossycobble = c_cobble;
 146         if (c_river_water_source == CONTENT_IGNORE)
 147                 c_river_water_source = c_water_source;
 148         if (c_sand == CONTENT_IGNORE)
 149                 c_sand = c_stone;
 150         if (c_sandstonebrick == CONTENT_IGNORE)
 151                 c_sandstonebrick = c_sandstone;
 152         if (c_stair_cobble == CONTENT_IGNORE)
 153                 c_stair_cobble = c_cobble;
 154         if (c_stair_sandstonebrick == CONTENT_IGNORE)
 155                 c_stair_sandstonebrick = c_sandstone;
 156 }
 157
 158
 159 MapgenValleys::~MapgenValleys()
 160 {
 161         delete noise_cave1;
 162         delete noise_cave2;
 163         delete noise_filler_depth;
 164         delete noise_heat;
 165         delete noise_heat_blend;
 166         delete noise_humidity;
 167         delete noise_humidity_blend;
 168         delete noise_inter_valley_fill;
 169         delete noise_inter_valley_slope;
 170         delete noise_rivers;
 171         delete noise_massive_caves;
 172         delete noise_terrain_height;
 173         delete noise_valley_depth;
 174         delete noise_valley_profile;
 175
 176         delete[] biomemap;
 177         delete[] heightmap;
 178         delete[] tcave_cache;
 179 }
 180
 181
 182 MapgenValleysParams::MapgenValleysParams()
 183 {
 184         spflags = MG_VALLEYS_HUMID_RIVERS | MG_VALLEYS_ALT_CHILL;
 185
 186         altitude_chill     = 90; // The altitude at which temperature drops by 20C.
 187         large_cave_depth   = -33;
 188         lava_features      = 0;  // How often water will occur in caves.
 189         massive_cave_depth = -256;  // highest altitude of massive caves
 190         river_depth        = 4;  // How deep to carve river channels.
 191         river_size         = 5;  // How wide to make rivers.
 192         water_features     = 0;  // How often water will occur in caves.
 193
 194         np_cave1              = NoiseParams(0,     12,   v3f(96,   96,   96),   52534, 4, 0.5,   2.0);
 195         np_cave2              = NoiseParams(0,     12,   v3f(96,   96,   96),   10325, 4, 0.5,   2.0);
 196         np_filler_depth       = NoiseParams(0.f,   1.2f, v3f(256,  256,  256),  1605,  3, 0.5f,  2.f);
 197         np_inter_valley_fill  = NoiseParams(0.f,   1.f,  v3f(256,  512,  256),  1993,  6, 0.8f,  2.f);
 198         np_inter_valley_slope = NoiseParams(0.5f,  0.5f, v3f(128,  128,  128),  746,   1, 1.f,   2.f);
 199         np_rivers             = NoiseParams(0.f,   1.f,  v3f(256,  256,  256),  -6050, 5, 0.6f,  2.f);
 200         np_massive_caves      = NoiseParams(0.f,   1.f,  v3f(768,  256,  768),  59033, 6, 0.63f, 2.f);
 201         np_terrain_height     = NoiseParams(-10.f, 50.f, v3f(1024, 1024, 1024), 5202,  6, 0.4f,  2.f);
 202         np_valley_depth       = NoiseParams(5.f,   4.f,  v3f(512,  512,  512),  -1914, 1, 1.f,   2.f);
 203         np_valley_profile     = NoiseParams(0.6f,  0.5f, v3f(512,  512,  512),  777,   1, 1.f,   2.f);
 204         }
 205
 206
 207 void MapgenValleysParams::readParams(const Settings *settings)
 208 {
 209         settings->getFlagStrNoEx("mg_valleys_spflags", spflags, flagdesc_mapgen_valleys);
 210
 211         settings->getU16NoEx("mg_valleys_altitude_chill",     altitude_chill);
 212         settings->getS16NoEx("mg_valleys_large_cave_depth",   large_cave_depth);
 213         settings->getU16NoEx("mg_valleys_lava_features",      lava_features);
 214         settings->getS16NoEx("mg_valleys_massive_cave_depth", massive_cave_depth);
 215         settings->getU16NoEx("mg_valleys_river_depth",        river_depth);
 216         settings->getU16NoEx("mg_valleys_river_size",         river_size);
 217         settings->getU16NoEx("mg_valleys_water_features",     water_features);
 218
 219         settings->getNoiseParams("mg_valleys_np_cave1",              np_cave1);
 220         settings->getNoiseParams("mg_valleys_np_cave2",              np_cave2);
 221         settings->getNoiseParams("mg_valleys_np_filler_depth",       np_filler_depth);
 222         settings->getNoiseParams("mg_valleys_np_inter_valley_fill",  np_inter_valley_fill);
 223         settings->getNoiseParams("mg_valleys_np_inter_valley_slope", np_inter_valley_slope);
 224         settings->getNoiseParams("mg_valleys_np_rivers",             np_rivers);
 225         settings->getNoiseParams("mg_valleys_np_massive_caves",      np_massive_caves);
 226         settings->getNoiseParams("mg_valleys_np_terrain_height",     np_terrain_height);
 227         settings->getNoiseParams("mg_valleys_np_valley_depth",       np_valley_depth);
 228         settings->getNoiseParams("mg_valleys_np_valley_profile",     np_valley_profile);
 229 }
 230
 231
 232 void MapgenValleysParams::writeParams(Settings *settings) const
 233 {
 234         settings->setFlagStr("mg_valleys_spflags", spflags, flagdesc_mapgen_valleys, U32_MAX);
 235
 236         settings->setU16("mg_valleys_altitude_chill",     altitude_chill);
 237         settings->setS16("mg_valleys_large_cave_depth",   large_cave_depth);
 238         settings->setU16("mg_valleys_lava_features",      lava_features);
 239         settings->setS16("mg_valleys_massive_cave_depth", massive_cave_depth);
 240         settings->setU16("mg_valleys_river_depth",        river_depth);
 241         settings->setU16("mg_valleys_river_size",         river_size);
 242         settings->setU16("mg_valleys_water_features",     water_features);
 243
 244         settings->setNoiseParams("mg_valleys_np_cave1",              np_cave1);
 245         settings->setNoiseParams("mg_valleys_np_cave2",              np_cave2);
 246         settings->setNoiseParams("mg_valleys_np_filler_depth",       np_filler_depth);
 247         settings->setNoiseParams("mg_valleys_np_inter_valley_fill",  np_inter_valley_fill);
 248         settings->setNoiseParams("mg_valleys_np_inter_valley_slope", np_inter_valley_slope);
 249         settings->setNoiseParams("mg_valleys_np_rivers",             np_rivers);
 250         settings->setNoiseParams("mg_valleys_np_massive_caves",      np_massive_caves);
 251         settings->setNoiseParams("mg_valleys_np_terrain_height",     np_terrain_height);
 252         settings->setNoiseParams("mg_valleys_np_valley_depth",       np_valley_depth);
 253         settings->setNoiseParams("mg_valleys_np_valley_profile",     np_valley_profile);
 254 }
 255
 256
 257 ///////////////////////////////////////
 258
 259
 260 void MapgenValleys::makeChunk(BlockMakeData *data)
 261 {
 262         // Pre-conditions
 263         assert(data->vmanip);
 264         assert(data->nodedef);
 265         assert(data->blockpos_requested.X >= data->blockpos_min.X &&
 266                 data->blockpos_requested.Y >= data->blockpos_min.Y &&
 267                 data->blockpos_requested.Z >= data->blockpos_min.Z);
 268         assert(data->blockpos_requested.X <= data->blockpos_max.X &&
 269                 data->blockpos_requested.Y <= data->blockpos_max.Y &&
 270                 data->blockpos_requested.Z <= data->blockpos_max.Z);
 271
 272         this->generating = true;
 273         this->vm = data->vmanip;
 274         this->ndef = data->nodedef;
 275
 276         //TimeTaker t("makeChunk");
 277
 278         v3s16 blockpos_min = data->blockpos_min;
 279         v3s16 blockpos_max = data->blockpos_max;
 280         node_min = blockpos_min * MAP_BLOCKSIZE;
 281         node_max = (blockpos_max + v3s16(1, 1, 1)) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
 282         full_node_min = (blockpos_min - 1) * MAP_BLOCKSIZE;
 283         full_node_max = (blockpos_max + 2) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
 284
 285         blockseed = getBlockSeed2(full_node_min, seed);
 286
 287         // Generate noise maps and base terrain height.
 288         calculateNoise();
 289
 290         // Generate base terrain with initial heightmaps
 291         s16 stone_surface_max_y = generateTerrain();
 292
 293         // Create biomemap at heightmap surface
 294         bmgr->calcBiomes(csize.X, csize.Z, heatmap, humidmap, heightmap, biomemap);
 295
 296         // Actually place the biome-specific nodes
 297         MgStoneType stone_type = generateBiomes(heatmap, humidmap);
 298
 299         // Cave creation.
 300         if (flags & MG_CAVES)
 301                 generateCaves(stone_surface_max_y);
 302
 303         // Dungeon creation
 304         if ((flags & MG_DUNGEONS) && node_max.Y < 50 && (stone_surface_max_y >= node_min.Y)) {
 305                 DungeonParams dp;
 306
 307                 dp.np_rarity  = nparams_dungeon_rarity;
 308                 dp.np_density = nparams_dungeon_density;
 309                 dp.np_wetness = nparams_dungeon_wetness;
 310                 dp.c_water    = c_water_source;
 311                 if (stone_type == STONE) {
 312                         dp.c_cobble = c_cobble;
 313                         dp.c_moss   = c_mossycobble;
 314                         dp.c_stair  = c_stair_cobble;
 315
 316                         dp.diagonal_dirs = false;
 317                         dp.mossratio     = 3.f;
 318                         dp.holesize      = v3s16(1, 2, 1);
 319                         dp.roomsize      = v3s16(0, 0, 0);
 320                         dp.notifytype    = GENNOTIFY_DUNGEON;
 321                 } else if (stone_type == DESERT_STONE) {
 322                         dp.c_cobble = c_desert_stone;
 323                         dp.c_moss   = c_desert_stone;
 324                         dp.c_stair  = c_desert_stone;
 325
 326                         dp.diagonal_dirs = true;
 327                         dp.mossratio     = 0.f;
 328                         dp.holesize      = v3s16(2, 3, 2);
 329                         dp.roomsize      = v3s16(2, 5, 2);
 330                         dp.notifytype    = GENNOTIFY_TEMPLE;
 331                 } else if (stone_type == SANDSTONE) {
 332                         dp.c_cobble = c_sandstonebrick;
 333                         dp.c_moss   = c_sandstonebrick;
 334                         dp.c_stair  = c_sandstonebrick;
 335
 336                         dp.diagonal_dirs = false;
 337                         dp.mossratio     = 0.f;
 338                         dp.holesize      = v3s16(2, 2, 2);
 339                         dp.roomsize      = v3s16(2, 0, 2);
 340                         dp.notifytype    = GENNOTIFY_DUNGEON;
 341                 }
 342
 343                 DungeonGen dgen(this, &dp);
 344                 dgen.generate(blockseed, full_node_min, full_node_max);
 345         }
 346
 347         // Generate the registered decorations
 348         if (flags & MG_DECORATIONS)
 349                 m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
 350
 351         // Generate the registered ores
 352         m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max);
 353
 354         // Sprinkle some dust on top after everything else was generated
 355         dustTopNodes();
 356
 357         //TimeTaker tll("liquid_lighting");
 358
 359         updateLiquid(&data->transforming_liquid, full_node_min, full_node_max);
 360
 361         if (flags & MG_LIGHT)
 362                 calcLighting(
 363                                 node_min - v3s16(0, 1, 0),
 364                                 node_max + v3s16(0, 1, 0),
 365                                 full_node_min,
 366                                 full_node_max);
 367
 368         //mapgen_profiler->avg("liquid_lighting", tll.stop() / 1000.f);
 369         //mapgen_profiler->avg("makeChunk", t.stop() / 1000.f);
 370
 371         this->generating = false;
 372 }
 373
 374
 375 // Populate the noise tables and do most of the
 376 // calculation necessary to determine terrain height.
 377 void MapgenValleys::calculateNoise()
 378 {
 379         //TimeTaker t("calculateNoise", NULL, PRECISION_MICRO);
 380
 381         int x = node_min.X;
 382         int y = node_min.Y - 1;
 383         int z = node_min.Z;
 384
 385         //TimeTaker tcn("actualNoise");
 386
 387         noise_filler_depth->perlinMap2D(x, z);
 388         noise_heat_blend->perlinMap2D(x, z);
 389         noise_heat->perlinMap2D(x, z);
 390         noise_humidity_blend->perlinMap2D(x, z);
 391         noise_humidity->perlinMap2D(x, z);
 392         noise_inter_valley_slope->perlinMap2D(x, z);
 393         noise_rivers->perlinMap2D(x, z);
 394         noise_terrain_height->perlinMap2D(x, z);
 395         noise_valley_depth->perlinMap2D(x, z);
 396         noise_valley_profile->perlinMap2D(x, z);
 397
 398         noise_inter_valley_fill->perlinMap3D(x, y, z);
 399
 400         //mapgen_profiler->avg("noisemaps", tcn.stop() / 1000.f);
 401
 402         for (s32 index = 0; index < csize.X * csize.Z; index++) {
 403                 noise_heat->result[index] += noise_heat_blend->result[index];
 404                 noise_humidity->result[index] += noise_humidity_blend->result[index];
 405         }
 406
 407         TerrainNoise tn;
 408
 409         u32 index = 0;
 410         for (tn.z = node_min.Z; tn.z <= node_max.Z; tn.z++)
 411         for (tn.x = node_min.X; tn.x <= node_max.X; tn.x++, index++) {
 412                 // The parameters that we actually need to generate terrain
 413                 //  are passed by address (and the return value).
 414                 tn.terrain_height    = noise_terrain_height->result[index];
 415                 // River noise is replaced with base terrain, which
 416                 // is basically the height of the water table.
 417                 tn.rivers            = &noise_rivers->result[index];
 418                 // Valley depth noise is replaced with the valley
 419                 // number that represents the height of terrain
 420                 // over rivers and is used to determine about
 421                 // how close a river is for humidity calculation.
 422                 tn.valley            = &noise_valley_depth->result[index];
 423                 tn.valley_profile    = noise_valley_profile->result[index];
 424                 // Slope noise is replaced by the calculated slope
 425                 // which is used to get terrain height in the slow
 426                 // method, to create sharper mountains.
 427                 tn.slope             = &noise_inter_valley_slope->result[index];
 428                 tn.inter_valley_fill = noise_inter_valley_fill->result[index];
 429
 430                 // This is the actual terrain height.
 431                 float mount = terrainLevelFromNoise(&tn);
 432                 noise_terrain_height->result[index] = mount;
 433         }
 434
 435         heatmap  = noise_heat->result;
 436         humidmap = noise_humidity->result;
 437 }
 438
 439
 440 // This keeps us from having to maintain two similar sets of
 441 //  complicated code to determine ground level.
 442 float MapgenValleys::terrainLevelFromNoise(TerrainNoise *tn)
 443 {
 444         // The square function changes the behaviour of this noise:
 445         //  very often small, and sometimes very high.
 446         float valley_d = MYSQUARE(*tn->valley);
 447
 448         // valley_d is here because terrain is generally higher where valleys
 449         //  are deep (mountains). base represents the height of the
 450         //  rivers, most of the surface is above.
 451         float base = tn->terrain_height + valley_d;
 452
 453         // "river" represents the distance from the river, in arbitrary units.
 454         float river = fabs(*tn->rivers) - river_size_factor;
 455
 456         // Use the curve of the function 1-exp(-(x/a)^2) to model valleys.
 457         //  Making "a" vary (0 < a <= 1) changes the shape of the valleys.
 458         //  Try it with a geometry software !
 459         //   (here x = "river" and a = valley_profile).
 460         //  "valley" represents the height of the terrain, from the rivers.
 461         {
 462                 float t = river / tn->valley_profile;
 463                 *tn->valley = valley_d * (1.f - exp(- MYSQUARE(t)));
 464         }
 465
 466         // approximate height of the terrain at this point
 467         float mount = base + *tn->valley;
 468
 469         *tn->slope *= *tn->valley;
 470
 471         // Rivers are placed where "river" is negative, so where the original
 472         //  noise value is close to zero.
 473         // Base ground is returned as rivers since it's basically the water table.
 474         *tn->rivers = base;
 475         if (river < 0.f) {
 476                 // Use the the function -sqrt(1-x^2) which models a circle.
 477                 float depth;
 478                 {
 479                         float t = river / river_size_factor + 1;
 480                         depth = (river_depth_bed * sqrt(MYMAX(0, 1.f - MYSQUARE(t))));
 481                 }
 482
 483                 // base - depth : height of the bottom of the river
 484                 // water_level - 6 : don't make rivers below 6 nodes under the surface
 485                 // There is no logical equivalent to this using rangelim.
 486                 mount = MYMIN(MYMAX(base - depth, (float) (water_level - 6)), mount);
 487
 488                 // Slope has no influence on rivers.
 489                 *tn->slope = 0.f;
 490         }
 491
 492         return mount;
 493 }
 494
 495
 496 // This avoids duplicating the code in terrainLevelFromNoise, adding
 497 // only the final step of terrain generation without a noise map.
 498 float MapgenValleys::adjustedTerrainLevelFromNoise(TerrainNoise *tn)
 499 {
 500         float mount = terrainLevelFromNoise(tn);
 501         s16 y_start = myround(mount);
 502
 503         for (s16 y = y_start; y <= y_start + 1000; y++) {
 504                 float fill = NoisePerlin3D(&noise_inter_valley_fill->np, tn->x, y, tn->z, seed);
 505
 506                 if (fill * *tn->slope <= y - mount) {
 507                         mount = MYMAX(y - 1, mount);
 508                         break;
 509                 }
 510         }
 511
 512         return mount;
 513 }
 514
 515
 516 int MapgenValleys::getGroundLevelAtPoint(v2s16 p)
 517 {
 518         // ***********************************
 519         // This method (deliberately) does not
 520         // return correct terrain values.
 521         // ***********************************
 522
 523         // Since MT doesn't normally deal with rivers, check
 524         // to make sure this isn't a request for a location
 525         // in a river.
 526         float rivers = NoisePerlin2D(&noise_rivers->np, p.X, p.Y, seed);
 527
 528         // If it's wet, return an unusable number.
 529         if (fabs(rivers) < river_size_factor)
 530                 return MAX_MAP_GENERATION_LIMIT;
 531
 532         // Otherwise, return the real result.
 533         return terrainLevelAtPoint(p.X, p.Y);
 534 }
 535
 536
 537 float MapgenValleys::terrainLevelAtPoint(s16 x, s16 z)
 538 {
 539         TerrainNoise tn;
 540
 541         float rivers = NoisePerlin2D(&noise_rivers->np, x, z, seed);
 542         float valley = NoisePerlin2D(&noise_valley_depth->np, x, z, seed);
 543         float inter_valley_slope = NoisePerlin2D(&noise_inter_valley_slope->np, x, z, seed);
 544
 545         tn.x                 = x;
 546         tn.z                 = z;
 547         tn.terrain_height    = NoisePerlin2D(&noise_terrain_height->np, x, z, seed);
 548         tn.rivers            = &rivers;
 549         tn.valley            = &valley;
 550         tn.valley_profile    = NoisePerlin2D(&noise_valley_profile->np, x, z, seed);
 551         tn.slope             = &inter_valley_slope;
 552         tn.inter_valley_fill = 0.f;
 553
 554         return adjustedTerrainLevelFromNoise(&tn);
 555 }
 556
 557
 558 int MapgenValleys::generateTerrain()
 559 {
 560         MapNode n_air(CONTENT_AIR);
 561         MapNode n_river_water(c_river_water_source);
 562         MapNode n_sand(c_sand);
 563         MapNode n_stone(c_stone);
 564         MapNode n_water(c_water_source);
 565
 566         v3s16 em = vm->m_area.getExtent();
 567         s16 surface_max_y = -MAX_MAP_GENERATION_LIMIT;
 568         u32 index_2d = 0;
 569
 570         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 571         for (s16 x = node_min.X; x <= node_max.X; x++, index_2d++) {
 572                 s16 river_y = floor(noise_rivers->result[index_2d]);
 573                 s16 surface_y = floor(noise_terrain_height->result[index_2d]);
 574                 float slope = noise_inter_valley_slope->result[index_2d];
 575
 576                 heightmap[index_2d] = surface_y;
 577
 578                 if (surface_y > surface_max_y)
 579                         surface_max_y = surface_y;
 580
 581                 u32 index_3d = (z - node_min.Z) * zstride + (x - node_min.X);
 582                 u32 index_data = vm->m_area.index(x, node_min.Y - 1, z);
 583
 584                 // Mapgens concern themselves with stone and water.
 585                 for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
 586                         float fill = 0.f;
 587                         fill = noise_inter_valley_fill->result[index_3d];
 588
 589                         if (vm->m_data[index_data].getContent() == CONTENT_IGNORE) {
 590                                 bool river = (river_y > surface_y);
 591
 592                                 if (river && y == surface_y) {
 593                                         // river bottom
 594                                         vm->m_data[index_data] = n_sand;
 595                                 } else if (river && y <= surface_y) {
 596                                         // ground
 597                                         vm->m_data[index_data] = n_stone;
 598                                 } else if (river && y < river_y) {
 599                                         // river
 600                                         vm->m_data[index_data] = n_river_water;
 601                                 } else if ((!river) && myround(fill * slope) >= y - surface_y) {
 602                                         // ground
 603                                         vm->m_data[index_data] = n_stone;
 604                                         heightmap[index_2d] = surface_max_y = y;
 605                                 } else if (y <= water_level) {
 606                                         // sea
 607                                         vm->m_data[index_data] = n_water;
 608                                 } else {
 609                                         vm->m_data[index_data] = n_air;
 610                                 }
 611                         }
 612
 613                         vm->m_area.add_y(em, index_data, 1);
 614                         index_3d += ystride;
 615                 }
 616
 617                 // Although the original valleys adjusts humidity by distance
 618                 // from seawater, this causes problems with the default biomes.
 619                 // Adjust only by freshwater proximity.
 620                 const float humidity_offset = 0.8f;  // derived by testing
 621                 if (humid_rivers)
 622                         noise_humidity->result[index_2d] *= (1 + pow(0.5f, MYMAX((surface_max_y
 623                                         - noise_rivers->result[index_2d]) / 3.f, 0.f))) * humidity_offset;
 624
 625                 // Assign the heat adjusted by altitude.
 626                 if (use_altitude_chill && surface_max_y > 0)
 627                         noise_heat->result[index_2d] *=
 628                                 pow(0.5f, (surface_max_y - altitude_chill / 3.f) / altitude_chill);
 629         }
 630
 631         return surface_max_y;
 632 }
 633
 634
 635 MgStoneType MapgenValleys::generateBiomes(float *heat_map, float *humidity_map)
 636 {
 637         v3s16 em = vm->m_area.getExtent();
 638         u32 index = 0;
 639         MgStoneType stone_type = STONE;
 640
 641         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 642         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
 643                 Biome *biome = NULL;
 644                 u16 depth_top = 0;
 645                 u16 base_filler = 0;
 646                 u16 depth_water_top = 0;
 647                 u32 vi = vm->m_area.index(x, node_max.Y, z);
 648
 649                 // Check node at base of mapchunk above, either a node of a previously
 650                 // generated mapchunk or if not, a node of overgenerated base terrain.
 651                 content_t c_above = vm->m_data[vi + em.X].getContent();
 652                 bool air_above = c_above == CONTENT_AIR;
 653                 bool water_above = (c_above == c_water_source);
 654
 655                 // If there is air or water above enable top/filler placement, otherwise force
 656                 // nplaced to stone level by setting a number exceeding any possible filler depth.
 657                 u16 nplaced = (air_above || water_above) ? 0 : U16_MAX;
 658
 659                 for (s16 y = node_max.Y; y >= node_min.Y; y--) {
 660                         content_t c = vm->m_data[vi].getContent();
 661
 662                         // Biome is recalculated each time an upper surface is detected while
 663                         // working down a column. The selected biome then remains in effect for
 664                         // all nodes below until the next surface and biome recalculation.
 665                         // Biome is recalculated:
 666                         // 1. At the surface of stone below air or water.
 667                         // 2. At the surface of water below air.
 668                         // 3. When stone or water is detected but biome has not yet been calculated.
 669                         if ((c == c_stone && (air_above || water_above || !biome))
 670                                         || ((c == c_water_source || c == c_river_water_source)
 671                                                         && (air_above || !biome))) {
 672                                 // Both heat and humidity have already been adjusted for altitude.
 673                                 biome = bmgr->getBiome(heat_map[index], humidity_map[index], y);
 674
 675                                 depth_top = biome->depth_top;
 676                                 base_filler = MYMAX(depth_top
 677                                                 + biome->depth_filler
 678                                                 + noise_filler_depth->result[index], 0.f);
 679                                 depth_water_top = biome->depth_water_top;
 680
 681                                 // Detect stone type for dungeons during every biome calculation.
 682                                 // This is more efficient than detecting per-node and will not
 683                                 // miss any desert stone or sandstone biomes.
 684                                 if (biome->c_stone == c_desert_stone)
 685                                         stone_type = DESERT_STONE;
 686                                 else if (biome->c_stone == c_sandstone)
 687                                         stone_type = SANDSTONE;
 688                         }
 689
 690                         if (c == c_stone) {
 691                                 content_t c_below = vm->m_data[vi - em.X].getContent();
 692
 693                                 // If the node below isn't solid, make this node stone, so that
 694                                 // any top/filler nodes above are structurally supported.
 695                                 // This is done by aborting the cycle of top/filler placement
 696                                 // immediately by forcing nplaced to stone level.
 697                                 if (c_below == CONTENT_AIR
 698                                                 || c_below == c_water_source
 699                                                 || c_below == c_river_water_source)
 700                                         nplaced = U16_MAX;
 701
 702                                 if (nplaced < depth_top) {
 703                                         vm->m_data[vi] = MapNode(biome->c_top);
 704                                         nplaced++;
 705                                 } else if (nplaced < base_filler) {
 706                                         vm->m_data[vi] = MapNode(biome->c_filler);
 707                                         nplaced++;
 708                                 } else {
 709                                         vm->m_data[vi] = MapNode(biome->c_stone);
 710                                 }
 711
 712                                 air_above = false;
 713                                 water_above = false;
 714                         } else if (c == c_water_source) {
 715                                 vm->m_data[vi] = MapNode((y > (s32)(water_level - depth_water_top))
 716                                                 ? biome->c_water_top : biome->c_water);
 717                                 nplaced = 0;  // Enable top/filler placement for next surface
 718                                 air_above = false;
 719                                 water_above = true;
 720                         } else if (c == c_river_water_source) {
 721                                 vm->m_data[vi] = MapNode(biome->c_river_water);
 722                                 nplaced = U16_MAX;  // Sand was already placed under rivers.
 723                                 air_above = false;
 724                                 water_above = true;
 725                         } else if (c == CONTENT_AIR) {
 726                                 nplaced = 0;  // Enable top/filler placement for next surface
 727                                 air_above = true;
 728                                 water_above = false;
 729                         } else {  // Possible various nodes overgenerated from neighbouring mapchunks
 730                                 nplaced = U16_MAX;  // Disable top/filler placement
 731                                 air_above = false;
 732                                 water_above = false;
 733                         }
 734
 735                         vm->m_area.add_y(em, vi, -1);
 736                 }
 737         }
 738
 739         return stone_type;
 740 }
 741
 742
 743 void MapgenValleys::dustTopNodes()
 744 {
 745         if (node_max.Y < water_level)
 746                 return;
 747
 748         v3s16 em = vm->m_area.getExtent();
 749         u32 index = 0;
 750
 751         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 752         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
 753                 Biome *biome = (Biome *)bmgr->getRaw(biomemap[index]);
 754
 755                 if (biome->c_dust == CONTENT_IGNORE)
 756                         continue;
 757
 758                 u32 vi = vm->m_area.index(x, full_node_max.Y, z);
 759                 content_t c_full_max = vm->m_data[vi].getContent();
 760                 s16 y_start;
 761
 762                 if (c_full_max == CONTENT_AIR) {
 763                         y_start = full_node_max.Y - 1;
 764                 } else if (c_full_max == CONTENT_IGNORE) {
 765                         vi = vm->m_area.index(x, node_max.Y + 1, z);
 766                         content_t c_max = vm->m_data[vi].getContent();
 767
 768                         if (c_max == CONTENT_AIR)
 769                                 y_start = node_max.Y;
 770                         else
 771                                 continue;
 772                 } else {
 773                         continue;
 774                 }
 775
 776                 vi = vm->m_area.index(x, y_start, z);
 777                 for (s16 y = y_start; y >= node_min.Y - 1; y--) {
 778                         if (vm->m_data[vi].getContent() != CONTENT_AIR)
 779                                 break;
 780
 781                         vm->m_area.add_y(em, vi, -1);
 782                 }
 783
 784                 content_t c = vm->m_data[vi].getContent();
 785                 if (!ndef->get(c).buildable_to && c != CONTENT_IGNORE && c != biome->c_dust) {
 786                         vm->m_area.add_y(em, vi, 1);
 787                         vm->m_data[vi] = MapNode(biome->c_dust);
 788                 }
 789         }
 790 }
 791
 792
 793 void MapgenValleys::generateCaves(s16 max_stone_y)
 794 {
 795         if (max_stone_y < node_min.Y)
 796                 return;
 797
 798         noise_cave1->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
 799         noise_cave2->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
 800
 801         PseudoRandom ps(blockseed + 72202);
 802
 803         MapNode n_air(CONTENT_AIR);
 804         MapNode n_lava(c_lava_source);
 805         MapNode n_water(c_river_water_source);
 806
 807         v3s16 em = vm->m_area.getExtent();
 808
 809         // Cave blend distance near YMIN, YMAX
 810         const float massive_cave_blend = 128.f;
 811         // noise threshold for massive caves
 812         const float massive_cave_threshold = 0.6f;
 813         // mct: 1 = small rare caves, 0.5 1/3rd ground volume, 0 = 1/2 ground volume.
 814
 815         float yblmin = -map_gen_limit + massive_cave_blend * 1.5f;
 816         float yblmax = massive_cave_depth - massive_cave_blend * 1.5f;
 817         bool made_a_big_one = false;
 818
 819         // Cache the tcave values as they only vary by altitude.
 820         if (node_max.Y <= massive_cave_depth) {
 821                 noise_massive_caves->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
 822
 823                 for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
 824                         float tcave = massive_cave_threshold;
 825
 826                         if (y < yblmin) {
 827                                 float t = (yblmin - y) / massive_cave_blend;
 828                                 tcave += MYSQUARE(t);
 829                         } else if (y > yblmax) {
 830                                 float t = (y - yblmax) / massive_cave_blend;
 831                                 tcave += MYSQUARE(t);
 832                         }
 833
 834                         tcave_cache[y - node_min.Y + 1] = tcave;
 835                 }
 836         }
 837
 838         // lava_depth varies between one and ten as you approach
 839         //  the bottom of the world.
 840         s16 lava_depth = ceil((lava_max_height - node_min.Y + 1) * 10.f / map_gen_limit);
 841         // This allows random lava spawns to be less common at the surface.
 842         s16 lava_chance = MYCUBE(lava_features_lim) * lava_depth;
 843         // water_depth varies between ten and one on the way down.
 844         s16 water_depth = ceil((map_gen_limit - abs(node_min.Y) + 1) * 10.f / map_gen_limit);
 845         // This allows random water spawns to be more common at the surface.
 846         s16 water_chance = MYCUBE(water_features_lim) * water_depth;
 847
 848         // Reduce the odds of overflows even further.
 849         if (node_max.Y > water_level) {
 850                 lava_chance /= 3;
 851                 water_chance /= 3;
 852         }
 853
 854         u32 index_2d = 0;
 855         u32 index_3d = 0;
 856         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 857         for (s16 x = node_min.X; x <= node_max.X; x++, index_2d++) {
 858                 Biome *biome = (Biome *)bmgr->getRaw(biomemap[index_2d]);
 859                 bool air_above = false;
 860                 bool underground = false;
 861                 u32 index_data = vm->m_area.index(x, node_max.Y + 1, z);
 862
 863                 index_3d = (z - node_min.Z) * zstride + (csize.Y + 1) * ystride + (x - node_min.X);
 864
 865                 // Dig caves on down loop to check for air above.
 866                 for (s16 y = node_max.Y + 1;
 867                                 y >= node_min.Y - 1;
 868                                 y--, index_3d -= ystride, vm->m_area.add_y(em, index_data, -1)) {
 869                         float terrain = noise_terrain_height->result[index_2d];
 870
 871                         // Saves some time.
 872                         if (y > terrain + 10) {
 873                                 air_above = true;
 874                                 continue;
 875                         } else if (y < terrain - 40) {
 876                                 underground = true;
 877                         }
 878
 879                         // Dig massive caves.
 880                         if (node_max.Y <= massive_cave_depth
 881                                         && noise_massive_caves->result[index_3d]
 882                                         > tcave_cache[y - node_min.Y + 1]) {
 883                                 vm->m_data[index_data] = n_air;
 884                                 made_a_big_one = true;
 885                         }
 886
 887                         content_t c = vm->m_data[index_data].getContent();
 888                         float d1 = contour(noise_cave1->result[index_3d]);
 889                         float d2 = contour(noise_cave2->result[index_3d]);
 890
 891                         // River water is not set as ground content
 892                         // in the default game. This can produce strange results
 893                         // when a cave undercuts a river. However, that's not for
 894                         // the mapgen to correct. Fix it in lua.
 895
 896                         if (c == CONTENT_AIR) {
 897                                 air_above = true;
 898                         } else if (d1 * d2 > 0.3f && ndef->get(c).is_ground_content) {
 899                                 // in a cave
 900                                 vm->m_data[index_data] = n_air;
 901                                 air_above = true;
 902                         } else if (air_above && (c == biome->c_filler || c == biome->c_stone)) {
 903                                 // at the cave floor
 904                                 s16 sr = ps.range(0,39);
 905                                 u32 j = index_data;
 906                                 vm->m_area.add_y(em, j, 1);
 907
 908                                 if (sr > terrain - y) {
 909                                         // Put dirt in caves near the surface.
 910                                         if (underground)
 911                                                 vm->m_data[index_data] = MapNode(biome->c_filler);
 912                                         else
 913                                                 vm->m_data[index_data] = MapNode(biome->c_top);
 914                                 } else if (sr < 3 && underground) {
 915                                         sr = abs(ps.next());
 916                                         if (lava_features_lim > 0 && y <= lava_max_height
 917                                                         && c == biome->c_stone && sr < lava_chance)
 918                                                 vm->m_data[j] = n_lava;
 919
 920                                         sr -= lava_chance;
 921
 922                                         // If sr < 0 then we should have already placed lava --
 923                                         // don't immediately dump water on it.
 924                                         if (water_features_lim > 0 && y <= cave_water_max_height
 925                                                         && sr >= 0 && sr < water_chance)
 926                                                 vm->m_data[j] = n_water;
 927                                 }
 928
 929                                 air_above = false;
 930                                 underground = true;
 931                         } else if (c == biome->c_filler || c == biome->c_stone) {
 932                                 air_above = false;
 933                                 underground = true;
 934                         } else {
 935                                 air_above = false;
 936                         }
 937                 }
 938         }
 939
 940         if (node_max.Y <= large_cave_depth && (!made_a_big_one)) {
 941                 u32 bruises_count = ps.range(0, 2);
 942                 for (u32 i = 0; i < bruises_count; i++) {
 943                         CaveV5 cave(this, &ps);
 944                         cave.makeCave(node_min, node_max, max_stone_y);
 945                 }
 946         }
 947 }