src/mapgen_v7.cpp

   1 /*
   2 Minetest
   3 Copyright (C) 2013-2016 kwolekr, Ryan Kwolek <kwolekr@minetest.net>
   4 Copyright (C) 2014-2017 paramat
   5
   6 This program is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU Lesser General Public License as published by
   8 the Free Software Foundation; either version 2.1 of the License, or
   9 (at your option) any later version.
  10
  11 This program is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU Lesser General Public License for more details.
  15
  16 You should have received a copy of the GNU Lesser General Public License along
  17 with this program; if not, write to the Free Software Foundation, Inc.,
  18 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19 */
  20
  21
  22 #include "mapgen.h"
  23 #include "voxel.h"
  24 #include "noise.h"
  25 #include "mapblock.h"
  26 #include "mapnode.h"
  27 #include "map.h"
  28 #include "content_sao.h"
  29 #include "nodedef.h"
  30 #include "voxelalgorithms.h"
  31 //#include "profiler.h" // For TimeTaker
  32 #include "settings.h" // For g_settings
  33 #include "emerge.h"
  34 #include "dungeongen.h"
  35 #include "cavegen.h"
  36 #include "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(int mapgenid, MapgenV7Params *params, EmergeManager *emerge)
  55         : MapgenBasic(mapgenid, params, emerge)
  56 {
  57         this->spflags             = params->spflags;
  58         this->cave_width          = params->cave_width;
  59         this->large_cave_depth    = params->large_cave_depth;
  60         this->lava_depth          = params->lava_depth;
  61         this->float_mount_density = params->float_mount_density;
  62         float_mount_height_lim    = MYMAX(params->float_mount_height, 1.0f);
  63         this->floatland_level     = params->floatland_level;
  64         this->shadow_limit        = params->shadow_limit;
  65         this->cavern_limit        = params->cavern_limit;
  66         this->cavern_taper        = params->cavern_taper;
  67         this->cavern_threshold    = params->cavern_threshold;
  68
  69         // 2D noise
  70         noise_terrain_base    = new Noise(&params->np_terrain_base,    seed, csize.X, csize.Z);
  71         noise_terrain_alt     = new Noise(&params->np_terrain_alt,     seed, csize.X, csize.Z);
  72         noise_terrain_persist = new Noise(&params->np_terrain_persist, seed, csize.X, csize.Z);
  73         noise_height_select   = new Noise(&params->np_height_select,   seed, csize.X, csize.Z);
  74         noise_filler_depth    = new Noise(&params->np_filler_depth,    seed, csize.X, csize.Z);
  75
  76         if (spflags & MGV7_MOUNTAINS)
  77                 noise_mount_height = new Noise(&params->np_mount_height, seed, csize.X, csize.Z);
  78
  79         if (spflags & MGV7_FLOATLANDS) {
  80                 noise_floatland_base    = new Noise(&params->np_floatland_base,    seed, csize.X, csize.Z);
  81                 noise_float_base_height = new Noise(&params->np_float_base_height, seed, csize.X, csize.Z);
  82         }
  83
  84         if (spflags & MGV7_RIDGES) {
  85                 noise_ridge_uwater = new Noise(&params->np_ridge_uwater, seed, csize.X, csize.Z);
  86         // 3D noise, 1-up 1-down overgeneration
  87                 noise_ridge = new Noise(&params->np_ridge, seed, csize.X, csize.Y + 2, csize.Z);
  88         }
  89         // 3D noise, 1 up, 1 down overgeneration
  90         if ((spflags & MGV7_MOUNTAINS) || (spflags & MGV7_FLOATLANDS))
  91                 noise_mountain = new Noise(&params->np_mountain, seed, csize.X, csize.Y + 2, csize.Z);
  92         // 3D noise, 1 down overgeneration
  93         MapgenBasic::np_cave1  = params->np_cave1;
  94         MapgenBasic::np_cave2  = params->np_cave2;
  95         MapgenBasic::np_cavern = params->np_cavern;
  96 }
  97
  98
  99 MapgenV7::~MapgenV7()
 100 {
 101         delete noise_terrain_base;
 102         delete noise_terrain_alt;
 103         delete noise_terrain_persist;
 104         delete noise_height_select;
 105         delete noise_filler_depth;
 106
 107         if (spflags & MGV7_MOUNTAINS)
 108                 delete noise_mount_height;
 109
 110         if (spflags & MGV7_FLOATLANDS) {
 111                 delete noise_floatland_base;
 112                 delete noise_float_base_height;
 113         }
 114
 115         if (spflags & MGV7_RIDGES) {
 116                 delete noise_ridge_uwater;
 117                 delete noise_ridge;
 118         }
 119
 120         if ((spflags & MGV7_MOUNTAINS) || (spflags & MGV7_FLOATLANDS))
 121                 delete noise_mountain;
 122 }
 123
 124
 125 MapgenV7Params::MapgenV7Params()
 126 {
 127         np_terrain_base      = NoiseParams(4,    70,   v3f(600,  600,  600),  82341, 5, 0.6,  2.0);
 128         np_terrain_alt       = NoiseParams(4,    25,   v3f(600,  600,  600),  5934,  5, 0.6,  2.0);
 129         np_terrain_persist   = NoiseParams(0.6,  0.1,  v3f(2000, 2000, 2000), 539,   3, 0.6,  2.0);
 130         np_height_select     = NoiseParams(-8,   16,   v3f(500,  500,  500),  4213,  6, 0.7,  2.0);
 131         np_filler_depth      = NoiseParams(0,    1.2,  v3f(150,  150,  150),  261,   3, 0.7,  2.0);
 132         np_mount_height      = NoiseParams(256,  112,  v3f(1000, 1000, 1000), 72449, 3, 0.6,  2.0);
 133         np_ridge_uwater      = NoiseParams(0,    1,    v3f(1000, 1000, 1000), 85039, 5, 0.6,  2.0);
 134         np_floatland_base    = NoiseParams(-0.6, 1.5,  v3f(600,  600,  600),  114,   5, 0.6,  2.0);
 135         np_float_base_height = NoiseParams(48,   24,   v3f(300,  300,  300),  907,   4, 0.7,  2.0);
 136         np_mountain          = NoiseParams(-0.6, 1,    v3f(250,  350,  250),  5333,  5, 0.63, 2.0);
 137         np_ridge             = NoiseParams(0,    1,    v3f(100,  100,  100),  6467,  4, 0.75, 2.0);
 138         np_cavern            = NoiseParams(0,    1,    v3f(384,  128,  384),  723,   5, 0.63, 2.0);
 139         np_cave1             = NoiseParams(0,    12,   v3f(61,   61,   61),   52534, 3, 0.5,  2.0);
 140         np_cave2             = NoiseParams(0,    12,   v3f(67,   67,   67),   10325, 3, 0.5,  2.0);
 141 }
 142
 143
 144 void MapgenV7Params::readParams(const Settings *settings)
 145 {
 146         settings->getFlagStrNoEx("mgv7_spflags",           spflags, flagdesc_mapgen_v7);
 147         settings->getFloatNoEx("mgv7_cave_width",          cave_width);
 148         settings->getS16NoEx("mgv7_large_cave_depth",      large_cave_depth);
 149         settings->getS16NoEx("mgv7_lava_depth",            lava_depth);
 150         settings->getFloatNoEx("mgv7_float_mount_density", float_mount_density);
 151         settings->getFloatNoEx("mgv7_float_mount_height",  float_mount_height);
 152         settings->getS16NoEx("mgv7_floatland_level",       floatland_level);
 153         settings->getS16NoEx("mgv7_shadow_limit",          shadow_limit);
 154         settings->getS16NoEx("mgv7_cavern_limit",          cavern_limit);
 155         settings->getS16NoEx("mgv7_cavern_taper",          cavern_taper);
 156         settings->getFloatNoEx("mgv7_cavern_threshold",    cavern_threshold);
 157
 158         settings->getNoiseParams("mgv7_np_terrain_base",      np_terrain_base);
 159         settings->getNoiseParams("mgv7_np_terrain_alt",       np_terrain_alt);
 160         settings->getNoiseParams("mgv7_np_terrain_persist",   np_terrain_persist);
 161         settings->getNoiseParams("mgv7_np_height_select",     np_height_select);
 162         settings->getNoiseParams("mgv7_np_filler_depth",      np_filler_depth);
 163         settings->getNoiseParams("mgv7_np_mount_height",      np_mount_height);
 164         settings->getNoiseParams("mgv7_np_ridge_uwater",      np_ridge_uwater);
 165         settings->getNoiseParams("mgv7_np_floatland_base",    np_floatland_base);
 166         settings->getNoiseParams("mgv7_np_float_base_height", np_float_base_height);
 167         settings->getNoiseParams("mgv7_np_mountain",          np_mountain);
 168         settings->getNoiseParams("mgv7_np_ridge",             np_ridge);
 169         settings->getNoiseParams("mgv7_np_cavern",            np_cavern);
 170         settings->getNoiseParams("mgv7_np_cave1",             np_cave1);
 171         settings->getNoiseParams("mgv7_np_cave2",             np_cave2);
 172 }
 173
 174
 175 void MapgenV7Params::writeParams(Settings *settings) const
 176 {
 177         settings->setFlagStr("mgv7_spflags",           spflags, flagdesc_mapgen_v7, U32_MAX);
 178         settings->setFloat("mgv7_cave_width",          cave_width);
 179         settings->setS16("mgv7_large_cave_depth",      large_cave_depth);
 180         settings->setS16("mgv7_lava_depth",            lava_depth);
 181         settings->setFloat("mgv7_float_mount_density", float_mount_density);
 182         settings->setFloat("mgv7_float_mount_height",  float_mount_height);
 183         settings->setS16("mgv7_floatland_level",       floatland_level);
 184         settings->setS16("mgv7_shadow_limit",          shadow_limit);
 185         settings->setS16("mgv7_cavern_limit",          cavern_limit);
 186         settings->setS16("mgv7_cavern_taper",          cavern_taper);
 187         settings->setFloat("mgv7_cavern_threshold",    cavern_threshold);
 188
 189         settings->setNoiseParams("mgv7_np_terrain_base",      np_terrain_base);
 190         settings->setNoiseParams("mgv7_np_terrain_alt",       np_terrain_alt);
 191         settings->setNoiseParams("mgv7_np_terrain_persist",   np_terrain_persist);
 192         settings->setNoiseParams("mgv7_np_height_select",     np_height_select);
 193         settings->setNoiseParams("mgv7_np_filler_depth",      np_filler_depth);
 194         settings->setNoiseParams("mgv7_np_mount_height",      np_mount_height);
 195         settings->setNoiseParams("mgv7_np_ridge_uwater",      np_ridge_uwater);
 196         settings->setNoiseParams("mgv7_np_floatland_base",    np_floatland_base);
 197         settings->setNoiseParams("mgv7_np_float_base_height", np_float_base_height);
 198         settings->setNoiseParams("mgv7_np_mountain",          np_mountain);
 199         settings->setNoiseParams("mgv7_np_ridge",             np_ridge);
 200         settings->setNoiseParams("mgv7_np_cavern",            np_cavern);
 201         settings->setNoiseParams("mgv7_np_cave1",             np_cave1);
 202         settings->setNoiseParams("mgv7_np_cave2",             np_cave2);
 203 }
 204
 205
 206 ///////////////////////////////////////////////////////////////////////////////
 207
 208
 209 int MapgenV7::getSpawnLevelAtPoint(v2s16 p)
 210 {
 211         // If rivers are enabled, first check if in a river
 212         if (spflags & MGV7_RIDGES) {
 213                 float width = 0.2;
 214                 float uwatern = NoisePerlin2D(&noise_ridge_uwater->np, p.X, p.Y, seed) * 2;
 215                 if (fabs(uwatern) <= width)
 216                         return MAX_MAP_GENERATION_LIMIT;  // Unsuitable spawn point
 217         }
 218
 219         // Terrain noise 'offset' is the average level of that terrain.
 220         // At least 50% of terrain will be below the higher of base and alt terrain
 221         // 'offset's.
 222         // Raising the maximum spawn level above 'water_level + 16' is necessary
 223         // for when terrain 'offset's are set much higher than water_level.
 224         s16 max_spawn_y = MYMAX(MYMAX(noise_terrain_alt->np.offset,
 225                         noise_terrain_base->np.offset),
 226                         water_level + 16);
 227         // Base terrain calculation
 228         s16 y = baseTerrainLevelAtPoint(p.X, p.Y);
 229
 230         // If mountains are disabled, terrain level is base terrain level.
 231         // Avoids mid-air spawn where mountain terrain would have been.
 232         if (!(spflags & MGV7_MOUNTAINS)) {
 233                 if (y <= water_level || y > max_spawn_y)
 234                         return MAX_MAP_GENERATION_LIMIT;  // Unsuitable spawn point
 235                 else
 236                         // + 1 to not be half-buried in a potential node-deep biome 'dust'
 237                         return y + 1;
 238         }
 239
 240         // Search upwards for first node without mountain terrain
 241         int iters = 256;
 242         while (iters > 0 && y <= max_spawn_y) {
 243                 if (!getMountainTerrainAtPoint(p.X, y + 1, p.Y)) {  // If air above
 244                         if (y <= water_level || y > max_spawn_y)
 245                                 return MAX_MAP_GENERATION_LIMIT;  // Unsuitable spawn point
 246                         else
 247                                 return y + 1;
 248                 }
 249                 y++;
 250                 iters--;
 251         }
 252
 253         // Unsuitable spawn point
 254         return MAX_MAP_GENERATION_LIMIT;
 255 }
 256
 257
 258 void MapgenV7::makeChunk(BlockMakeData *data)
 259 {
 260         // Pre-conditions
 261         assert(data->vmanip);
 262         assert(data->nodedef);
 263         assert(data->blockpos_requested.X >= data->blockpos_min.X &&
 264                 data->blockpos_requested.Y >= data->blockpos_min.Y &&
 265                 data->blockpos_requested.Z >= data->blockpos_min.Z);
 266         assert(data->blockpos_requested.X <= data->blockpos_max.X &&
 267                 data->blockpos_requested.Y <= data->blockpos_max.Y &&
 268                 data->blockpos_requested.Z <= data->blockpos_max.Z);
 269
 270         this->generating = true;
 271         this->vm   = data->vmanip;
 272         this->ndef = data->nodedef;
 273         //TimeTaker t("makeChunk");
 274
 275         v3s16 blockpos_min = data->blockpos_min;
 276         v3s16 blockpos_max = data->blockpos_max;
 277         node_min = blockpos_min * MAP_BLOCKSIZE;
 278         node_max = (blockpos_max + v3s16(1, 1, 1)) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
 279         full_node_min = (blockpos_min - 1) * MAP_BLOCKSIZE;
 280         full_node_max = (blockpos_max + 2) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
 281
 282         blockseed = getBlockSeed2(full_node_min, seed);
 283
 284         // Generate base and mountain terrain
 285         // An initial heightmap is no longer created here for use in generateRidgeTerrain()
 286         s16 stone_surface_max_y = generateTerrain();
 287
 288         // Generate rivers
 289         if (spflags & MGV7_RIDGES)
 290                 generateRidgeTerrain();
 291
 292         // Create heightmap
 293         updateHeightmap(node_min, node_max);
 294
 295         // Init biome generator, place biome-specific nodes, and build biomemap
 296         biomegen->calcBiomeNoise(node_min);
 297         MgStoneType stone_type = generateBiomes();
 298
 299         // Generate caverns, tunnels and classic caves
 300         if (flags & MG_CAVES) {
 301                 bool near_cavern = false;
 302                 // Generate caverns
 303                 if (spflags & MGV7_CAVERNS)
 304                         near_cavern = generateCaverns(stone_surface_max_y);
 305                 // Generate tunnels and classic caves
 306                 if (near_cavern)
 307                         // Disable classic caves in this mapchunk by setting
 308                         // 'large cave depth' to world base. Avoids excessive liquid in
 309                         // large caverns and floating blobs of overgenerated liquid.
 310                         generateCaves(stone_surface_max_y, -MAX_MAP_GENERATION_LIMIT);
 311                 else
 312                         generateCaves(stone_surface_max_y, large_cave_depth);
 313         }
 314
 315         // Generate dungeons
 316         if (flags & MG_DUNGEONS)
 317                 generateDungeons(stone_surface_max_y, stone_type);
 318
 319         // Generate the registered decorations
 320         if (flags & MG_DECORATIONS)
 321                 m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
 322
 323         // Generate the registered ores
 324         m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max);
 325
 326         // Sprinkle some dust on top after everything else was generated
 327         dustTopNodes();
 328
 329         //printf("makeChunk: %dms\n", t.stop());
 330
 331         // Update liquids
 332         updateLiquid(&data->transforming_liquid, full_node_min, full_node_max);
 333
 334         // Calculate lighting
 335         // Limit floatland shadow
 336         bool propagate_shadow = !((spflags & MGV7_FLOATLANDS) &&
 337                 node_min.Y <= shadow_limit && node_max.Y >= shadow_limit);
 338
 339         if (flags & MG_LIGHT)
 340                 calcLighting(node_min - v3s16(0, 1, 0), node_max + v3s16(0, 1, 0),
 341                         full_node_min, full_node_max, propagate_shadow);
 342
 343         //setLighting(node_min - v3s16(1, 0, 1) * MAP_BLOCKSIZE,
 344         //                      node_max + v3s16(1, 0, 1) * MAP_BLOCKSIZE, 0xFF);
 345
 346         this->generating = false;
 347 }
 348
 349
 350 float MapgenV7::baseTerrainLevelAtPoint(s16 x, s16 z)
 351 {
 352         float hselect = NoisePerlin2D(&noise_height_select->np, x, z, seed);
 353         hselect = rangelim(hselect, 0.0, 1.0);
 354
 355         float persist = NoisePerlin2D(&noise_terrain_persist->np, x, z, seed);
 356
 357         noise_terrain_base->np.persist = persist;
 358         float height_base = NoisePerlin2D(&noise_terrain_base->np, x, z, seed);
 359
 360         noise_terrain_alt->np.persist = persist;
 361         float height_alt = NoisePerlin2D(&noise_terrain_alt->np, x, z, seed);
 362
 363         if (height_alt > height_base)
 364                 return height_alt;
 365
 366         return (height_base * hselect) + (height_alt * (1.0 - hselect));
 367 }
 368
 369
 370 float MapgenV7::baseTerrainLevelFromMap(int index)
 371 {
 372         float hselect     = rangelim(noise_height_select->result[index], 0.0, 1.0);
 373         float height_base = noise_terrain_base->result[index];
 374         float height_alt  = noise_terrain_alt->result[index];
 375
 376         if (height_alt > height_base)
 377                 return height_alt;
 378
 379         return (height_base * hselect) + (height_alt * (1.0 - hselect));
 380 }
 381
 382
 383 bool MapgenV7::getMountainTerrainAtPoint(s16 x, s16 y, s16 z)
 384 {
 385         float mnt_h_n =
 386                         MYMAX(NoisePerlin2D(&noise_mount_height->np, x, z, seed), 1.0f);
 387         float density_gradient = -((float)y / mnt_h_n);
 388         float mnt_n = NoisePerlin3D(&noise_mountain->np, x, y, z, seed);
 389
 390         return mnt_n + density_gradient >= 0.0;
 391 }
 392
 393
 394 bool MapgenV7::getMountainTerrainFromMap(int idx_xyz, int idx_xz, s16 y)
 395 {
 396         float mounthn = MYMAX(noise_mount_height->result[idx_xz], 1.0f);
 397         float density_gradient = -((float)y / mounthn);
 398         float mountn = noise_mountain->result[idx_xyz];
 399
 400         return mountn + density_gradient >= 0.0;
 401 }
 402
 403
 404 bool MapgenV7::getFloatlandMountainFromMap(int idx_xyz, int idx_xz, s16 y)
 405 {
 406         // Make rim 2 nodes thick to match floatland base terrain
 407         float density_gradient = (y >= floatland_level) ?
 408                 -pow((float)(y - floatland_level) / float_mount_height_lim, 0.75f) :
 409                 -pow((float)(floatland_level - 1 - y) / float_mount_height_lim, 0.75f);
 410
 411         float floatn = noise_mountain->result[idx_xyz] + float_mount_density;
 412
 413         return floatn + density_gradient >= 0.0f;
 414 }
 415
 416
 417 void MapgenV7::floatBaseExtentFromMap(s16 *float_base_min, s16 *float_base_max, int idx_xz)
 418 {
 419         // '+1' to avoid a layer of stone at y = MAX_MAP_GENERATION_LIMIT
 420         s16 base_min = MAX_MAP_GENERATION_LIMIT + 1;
 421         s16 base_max = MAX_MAP_GENERATION_LIMIT;
 422
 423         float n_base = noise_floatland_base->result[idx_xz];
 424         if (n_base > 0.0f) {
 425                 float n_base_height =
 426                                 MYMAX(noise_float_base_height->result[idx_xz], 1.0f);
 427                 float amp = n_base * n_base_height;
 428                 float ridge = n_base_height / 3.0f;
 429                 base_min = floatland_level - amp / 1.5f;
 430
 431                 if (amp > ridge * 2.0f) {
 432                         // Lake bed
 433                         base_max = floatland_level - (amp - ridge * 2.0f) / 2.0f;
 434                 } else {
 435                         // Hills and ridges
 436                         float diff = fabs(amp - ridge) / ridge;
 437                         // Smooth ridges using the 'smoothstep function'
 438                         float smooth_diff = diff * diff * (3.0f - 2.0f * diff);
 439                         base_max = floatland_level + ridge - smooth_diff * ridge;
 440                 }
 441         }
 442
 443         *float_base_min = base_min;
 444         *float_base_max = base_max;
 445 }
 446
 447
 448 int MapgenV7::generateTerrain()
 449 {
 450         MapNode n_air(CONTENT_AIR);
 451         MapNode n_stone(c_stone);
 452         MapNode n_water(c_water_source);
 453
 454         //// Calculate noise for terrain generation
 455         noise_terrain_persist->perlinMap2D(node_min.X, node_min.Z);
 456         float *persistmap = noise_terrain_persist->result;
 457
 458         noise_terrain_base->perlinMap2D(node_min.X, node_min.Z, persistmap);
 459         noise_terrain_alt->perlinMap2D(node_min.X, node_min.Z, persistmap);
 460         noise_height_select->perlinMap2D(node_min.X, node_min.Z);
 461
 462         if ((spflags & MGV7_MOUNTAINS) || (spflags & MGV7_FLOATLANDS)) {
 463                 noise_mountain->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
 464         }
 465
 466         if (spflags & MGV7_MOUNTAINS) {
 467                 noise_mount_height->perlinMap2D(node_min.X, node_min.Z);
 468         }
 469
 470         if (spflags & MGV7_FLOATLANDS) {
 471                 noise_floatland_base->perlinMap2D(node_min.X, node_min.Z);
 472                 noise_float_base_height->perlinMap2D(node_min.X, node_min.Z);
 473         }
 474
 475         //// Place nodes
 476         v3s16 em = vm->m_area.getExtent();
 477         s16 stone_surface_max_y = -MAX_MAP_GENERATION_LIMIT;
 478         u32 index2d = 0;
 479
 480         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 481         for (s16 x = node_min.X; x <= node_max.X; x++, index2d++) {
 482                 s16 surface_y = baseTerrainLevelFromMap(index2d);
 483                 if (surface_y > stone_surface_max_y)
 484                         stone_surface_max_y = surface_y;
 485
 486                 // Get extent of floatland base terrain
 487                 // '+1' to avoid a layer of stone at y = MAX_MAP_GENERATION_LIMIT
 488                 s16 float_base_min = MAX_MAP_GENERATION_LIMIT + 1;
 489                 s16 float_base_max = MAX_MAP_GENERATION_LIMIT;
 490                 if (spflags & MGV7_FLOATLANDS)
 491                         floatBaseExtentFromMap(&float_base_min, &float_base_max, index2d);
 492
 493                 u32 vi = vm->m_area.index(x, node_min.Y - 1, z);
 494                 u32 index3d = (z - node_min.Z) * zstride_1u1d + (x - node_min.X);
 495
 496                 for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
 497                         if (vm->m_data[vi].getContent() == CONTENT_IGNORE) {
 498                                 if (y <= surface_y) {
 499                                         vm->m_data[vi] = n_stone;  // Base terrain
 500                                 } else if ((spflags & MGV7_MOUNTAINS) &&
 501                                                 getMountainTerrainFromMap(index3d, index2d, y)) {
 502                                         vm->m_data[vi] = n_stone;  // Mountain terrain
 503                                         if (y > stone_surface_max_y)
 504                                                 stone_surface_max_y = y;
 505                                 } else if ((spflags & MGV7_FLOATLANDS) &&
 506                                                 ((y >= float_base_min && y <= float_base_max) ||
 507                                                 getFloatlandMountainFromMap(index3d, index2d, y))) {
 508                                         vm->m_data[vi] = n_stone;  // Floatland terrain
 509                                         stone_surface_max_y = node_max.Y;
 510                                 } else if (y <= water_level) {
 511                                         vm->m_data[vi] = n_water;  // Ground level water
 512                                 } else if ((spflags & MGV7_FLOATLANDS) &&
 513                                                 (y >= float_base_max && y <= floatland_level)) {
 514                                         vm->m_data[vi] = n_water;  // Floatland water
 515                                 } else {
 516                                         vm->m_data[vi] = n_air;
 517                                 }
 518                         }
 519                         vm->m_area.add_y(em, vi, 1);
 520                         index3d += ystride;
 521                 }
 522         }
 523
 524         return stone_surface_max_y;
 525 }
 526
 527
 528 void MapgenV7::generateRidgeTerrain()
 529 {
 530         if (node_max.Y < water_level - 16 ||
 531                         ((spflags & MGV7_FLOATLANDS) && node_max.Y > shadow_limit))
 532                 return;
 533
 534         noise_ridge->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
 535         noise_ridge_uwater->perlinMap2D(node_min.X, node_min.Z);
 536
 537         MapNode n_water(c_water_source);
 538         MapNode n_air(CONTENT_AIR);
 539         u32 index = 0;
 540         float width = 0.2;
 541
 542         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 543         for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
 544                 u32 vi = vm->m_area.index(node_min.X, y, z);
 545                 for (s16 x = node_min.X; x <= node_max.X; x++, index++, vi++) {
 546                         int j = (z - node_min.Z) * csize.X + (x - node_min.X);
 547
 548                         float uwatern = noise_ridge_uwater->result[j] * 2;
 549                         if (fabs(uwatern) > width)
 550                                 continue;
 551
 552                         float altitude = y - water_level;
 553                         float height_mod = (altitude + 17) / 2.5;
 554                         float width_mod  = width - fabs(uwatern);
 555                         float nridge = noise_ridge->result[index] * MYMAX(altitude, 0) / 7.0;
 556
 557                         if (nridge + width_mod * height_mod < 0.6)
 558                                 continue;
 559
 560                         vm->m_data[vi] = (y > water_level) ? n_air : n_water;
 561                 }
 562         }
 563 }
 564
 565
 566 ////////////////////////////////////////////////////////////////////////////////
 567 //// Code Boneyard
 568 ////
 569 //// Much of the stuff here has potential to become useful again at some point
 570 //// in the future, but we don't want it to get lost or forgotten in version
 571 //// control.
 572 ////
 573
 574 #if 0
 575 int MapgenV7::generateMountainTerrain(s16 ymax)
 576 {
 577         MapNode n_stone(c_stone);
 578         u32 j = 0;
 579
 580         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 581         for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
 582                 u32 vi = vm->m_area.index(node_min.X, y, z);
 583                 for (s16 x = node_min.X; x <= node_max.X; x++) {
 584                         int index = (z - node_min.Z) * csize.X + (x - node_min.X);
 585                         content_t c = vm->m_data[vi].getContent();
 586
 587                         if (getMountainTerrainFromMap(j, index, y)
 588                                         && (c == CONTENT_AIR || c == c_water_source)) {
 589                                 vm->m_data[vi] = n_stone;
 590                                 if (y > ymax)
 591                                         ymax = y;
 592                         }
 593
 594                         vi++;
 595                         j++;
 596                 }
 597         }
 598
 599         return ymax;
 600 }
 601 #endif
 602
 603
 604 #if 0
 605 void MapgenV7::carveRivers() {
 606         MapNode n_air(CONTENT_AIR), n_water_source(c_water_source);
 607         MapNode n_stone(c_stone);
 608         u32 index = 0;
 609
 610         int river_depth = 4;
 611
 612         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 613         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
 614                 float terrain_mod  = noise_terrain_mod->result[index];
 615                 NoiseParams *np = noise_terrain_river->np;
 616                 np.persist = noise_terrain_persist->result[index];
 617                 float terrain_river = NoisePerlin2DNoTxfm(np, x, z, seed);
 618                 float height = terrain_river * (1 - abs(terrain_mod)) *
 619                                                 noise_terrain_river->np.scale;
 620                 height = log(height * height); //log(h^3) is pretty interesting for terrain
 621
 622                 s16 y = heightmap[index];
 623                 if (height < 1.0 && y > river_depth &&
 624                         y - river_depth >= node_min.Y && y <= node_max.Y) {
 625
 626                         for (s16 ry = y; ry != y - river_depth; ry--) {
 627                                 u32 vi = vm->m_area.index(x, ry, z);
 628                                 vm->m_data[vi] = n_air;
 629                         }
 630
 631                         u32 vi = vm->m_area.index(x, y - river_depth, z);
 632                         vm->m_data[vi] = n_water_source;
 633                 }
 634         }
 635 }
 636 #endif
 637
 638
 639 #if 0
 640 void MapgenV7::addTopNodes()
 641 {
 642         v3s16 em = vm->m_area.getExtent();
 643         s16 ntopnodes;
 644         u32 index = 0;
 645
 646         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 647         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
 648                 Biome *biome = bmgr->biomes[biomemap[index]];
 649
 650                 //////////////////// First, add top nodes below the ridge
 651                 s16 y = ridge_heightmap[index];
 652
 653                 // This cutoff is good enough, but not perfect.
 654                 // It will cut off potentially placed top nodes at chunk boundaries
 655                 if (y < node_min.Y)
 656                         continue;
 657                 if (y > node_max.Y) {
 658                         y = node_max.Y; // Let's see if we can still go downward anyway
 659                         u32 vi = vm->m_area.index(x, y, z);
 660                         content_t c = vm->m_data[vi].getContent();
 661                         if (ndef->get(c).walkable)
 662                                 continue;
 663                 }
 664
 665                 // N.B.  It is necessary to search downward since ridge_heightmap[i]
 666                 // might not be the actual height, just the lowest part in the chunk
 667                 // where a ridge had been carved
 668                 u32 i = vm->m_area.index(x, y, z);
 669                 for (; y >= node_min.Y; y--) {
 670                         content_t c = vm->m_data[i].getContent();
 671                         if (ndef->get(c).walkable)
 672                                 break;
 673                         vm->m_area.add_y(em, i, -1);
 674                 }
 675
 676                 if (y != node_min.Y - 1 && y >= water_level) {
 677                         ridge_heightmap[index] = y; //update ridgeheight
 678                         ntopnodes = biome->top_depth;
 679                         for (; y <= node_max.Y && ntopnodes; y++) {
 680                                 ntopnodes--;
 681                                 vm->m_data[i] = MapNode(biome->c_top);
 682                                 vm->m_area.add_y(em, i, 1);
 683                         }
 684                         // If dirt, grow grass on it.
 685                         if (y > water_level - 10 &&
 686                                 vm->m_data[i].getContent() == CONTENT_AIR) {
 687                                 vm->m_area.add_y(em, i, -1);
 688                                 if (vm->m_data[i].getContent() == c_dirt)
 689                                         vm->m_data[i] = MapNode(c_dirt_with_grass);
 690                         }
 691                 }
 692
 693                 //////////////////// Now, add top nodes on top of the ridge
 694                 y = heightmap[index];
 695                 if (y > node_max.Y) {
 696                         y = node_max.Y; // Let's see if we can still go downward anyway
 697                         u32 vi = vm->m_area.index(x, y, z);
 698                         content_t c = vm->m_data[vi].getContent();
 699                         if (ndef->get(c).walkable)
 700                                 continue;
 701                 }
 702
 703                 i = vm->m_area.index(x, y, z);
 704                 for (; y >= node_min.Y; y--) {
 705                         content_t c = vm->m_data[i].getContent();
 706                         if (ndef->get(c).walkable)
 707                                 break;
 708                         vm->m_area.add_y(em, i, -1);
 709                 }
 710
 711                 if (y != node_min.Y - 1) {
 712                         ntopnodes = biome->top_depth;
 713                         // Let's see if we've already added it...
 714                         if (y == ridge_heightmap[index] + ntopnodes - 1)
 715                                 continue;
 716
 717                         for (; y <= node_max.Y && ntopnodes; y++) {
 718                                 ntopnodes--;
 719                                 vm->m_data[i] = MapNode(biome->c_top);
 720                                 vm->m_area.add_y(em, i, 1);
 721                         }
 722                         // If dirt, grow grass on it.
 723                         if (y > water_level - 10 &&
 724                                 vm->m_data[i].getContent() == CONTENT_AIR) {
 725                                 vm->m_area.add_y(em, i, -1);
 726                                 if (vm->m_data[i].getContent() == c_dirt)
 727                                         vm->m_data[i] = MapNode(c_dirt_with_grass);
 728                         }
 729                 }
 730         }
 731 }
 732 #endif