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         this->floatland_level     = params->floatland_level;
  63         this->shadow_limit        = params->shadow_limit;
  64         this->cavern_limit        = params->cavern_limit;
  65         this->cavern_taper        = params->cavern_taper;
  66         this->cavern_threshold    = params->cavern_threshold;
  67
  68         // This is to avoid a divide-by-zero.
  69         // Parameter will be saved to map_meta.txt in limited form.
  70         params->float_mount_height = MYMAX(params->float_mount_height, 1.0f);
  71
  72         // 2D noise
  73         noise_terrain_base    = new Noise(&params->np_terrain_base,    seed, csize.X, csize.Z);
  74         noise_terrain_alt     = new Noise(&params->np_terrain_alt,     seed, csize.X, csize.Z);
  75         noise_terrain_persist = new Noise(&params->np_terrain_persist, seed, csize.X, csize.Z);
  76         noise_height_select   = new Noise(&params->np_height_select,   seed, csize.X, csize.Z);
  77         noise_filler_depth    = new Noise(&params->np_filler_depth,    seed, csize.X, csize.Z);
  78
  79         if (spflags & MGV7_MOUNTAINS)
  80                 noise_mount_height = new Noise(&params->np_mount_height, seed, csize.X, csize.Z);
  81
  82         if (spflags & MGV7_FLOATLANDS) {
  83                 noise_floatland_base    = new Noise(&params->np_floatland_base,    seed, csize.X, csize.Z);
  84                 noise_float_base_height = new Noise(&params->np_float_base_height, seed, csize.X, csize.Z);
  85         }
  86
  87         if (spflags & MGV7_RIDGES) {
  88                 noise_ridge_uwater = new Noise(&params->np_ridge_uwater, seed, csize.X, csize.Z);
  89         // 3D noise, 1-up 1-down overgeneration
  90                 noise_ridge = new Noise(&params->np_ridge, seed, csize.X, csize.Y + 2, csize.Z);
  91         }
  92         // 3D noise, 1 up, 1 down overgeneration
  93         if ((spflags & MGV7_MOUNTAINS) || (spflags & MGV7_FLOATLANDS))
  94                 noise_mountain = new Noise(&params->np_mountain, seed, csize.X, csize.Y + 2, csize.Z);
  95         // 3D noise, 1 down overgeneration
  96         MapgenBasic::np_cave1  = params->np_cave1;
  97         MapgenBasic::np_cave2  = params->np_cave2;
  98         MapgenBasic::np_cavern = params->np_cavern;
  99 }
 100
 101
 102 MapgenV7::~MapgenV7()
 103 {
 104         delete noise_terrain_base;
 105         delete noise_terrain_alt;
 106         delete noise_terrain_persist;
 107         delete noise_height_select;
 108         delete noise_filler_depth;
 109
 110         if (spflags & MGV7_MOUNTAINS)
 111                 delete noise_mount_height;
 112
 113         if (spflags & MGV7_FLOATLANDS) {
 114                 delete noise_floatland_base;
 115                 delete noise_float_base_height;
 116         }
 117
 118         if (spflags & MGV7_RIDGES) {
 119                 delete noise_ridge_uwater;
 120                 delete noise_ridge;
 121         }
 122
 123         if ((spflags & MGV7_MOUNTAINS) || (spflags & MGV7_FLOATLANDS))
 124                 delete noise_mountain;
 125 }
 126
 127
 128 MapgenV7Params::MapgenV7Params()
 129 {
 130         np_terrain_base      = NoiseParams(4,    70,   v3f(600,  600,  600),  82341, 5, 0.6,  2.0);
 131         np_terrain_alt       = NoiseParams(4,    25,   v3f(600,  600,  600),  5934,  5, 0.6,  2.0);
 132         np_terrain_persist   = NoiseParams(0.6,  0.1,  v3f(2000, 2000, 2000), 539,   3, 0.6,  2.0);
 133         np_height_select     = NoiseParams(-8,   16,   v3f(500,  500,  500),  4213,  6, 0.7,  2.0);
 134         np_filler_depth      = NoiseParams(0,    1.2,  v3f(150,  150,  150),  261,   3, 0.7,  2.0);
 135         np_mount_height      = NoiseParams(256,  112,  v3f(1000, 1000, 1000), 72449, 3, 0.6,  2.0);
 136         np_ridge_uwater      = NoiseParams(0,    1,    v3f(1000, 1000, 1000), 85039, 5, 0.6,  2.0);
 137         np_floatland_base    = NoiseParams(-0.6, 1.5,  v3f(600,  600,  600),  114,   5, 0.6,  2.0);
 138         np_float_base_height = NoiseParams(48,   24,   v3f(300,  300,  300),  907,   4, 0.7,  2.0);
 139         np_mountain          = NoiseParams(-0.6, 1,    v3f(250,  350,  250),  5333,  5, 0.63, 2.0);
 140         np_ridge             = NoiseParams(0,    1,    v3f(100,  100,  100),  6467,  4, 0.75, 2.0);
 141         np_cavern            = NoiseParams(0,    1,    v3f(384,  128,  384),  723,   5, 0.63, 2.0);
 142         np_cave1             = NoiseParams(0,    12,   v3f(61,   61,   61),   52534, 3, 0.5,  2.0);
 143         np_cave2             = NoiseParams(0,    12,   v3f(67,   67,   67),   10325, 3, 0.5,  2.0);
 144 }
 145
 146
 147 void MapgenV7Params::readParams(const Settings *settings)
 148 {
 149         settings->getFlagStrNoEx("mgv7_spflags",           spflags, flagdesc_mapgen_v7);
 150         settings->getFloatNoEx("mgv7_cave_width",          cave_width);
 151         settings->getS16NoEx("mgv7_large_cave_depth",      large_cave_depth);
 152         settings->getS16NoEx("mgv7_lava_depth",            lava_depth);
 153         settings->getFloatNoEx("mgv7_float_mount_density", float_mount_density);
 154         settings->getFloatNoEx("mgv7_float_mount_height",  float_mount_height);
 155         settings->getS16NoEx("mgv7_floatland_level",       floatland_level);
 156         settings->getS16NoEx("mgv7_shadow_limit",          shadow_limit);
 157         settings->getS16NoEx("mgv7_cavern_limit",          cavern_limit);
 158         settings->getS16NoEx("mgv7_cavern_taper",          cavern_taper);
 159         settings->getFloatNoEx("mgv7_cavern_threshold",    cavern_threshold);
 160
 161         settings->getNoiseParams("mgv7_np_terrain_base",      np_terrain_base);
 162         settings->getNoiseParams("mgv7_np_terrain_alt",       np_terrain_alt);
 163         settings->getNoiseParams("mgv7_np_terrain_persist",   np_terrain_persist);
 164         settings->getNoiseParams("mgv7_np_height_select",     np_height_select);
 165         settings->getNoiseParams("mgv7_np_filler_depth",      np_filler_depth);
 166         settings->getNoiseParams("mgv7_np_mount_height",      np_mount_height);
 167         settings->getNoiseParams("mgv7_np_ridge_uwater",      np_ridge_uwater);
 168         settings->getNoiseParams("mgv7_np_floatland_base",    np_floatland_base);
 169         settings->getNoiseParams("mgv7_np_float_base_height", np_float_base_height);
 170         settings->getNoiseParams("mgv7_np_mountain",          np_mountain);
 171         settings->getNoiseParams("mgv7_np_ridge",             np_ridge);
 172         settings->getNoiseParams("mgv7_np_cavern",            np_cavern);
 173         settings->getNoiseParams("mgv7_np_cave1",             np_cave1);
 174         settings->getNoiseParams("mgv7_np_cave2",             np_cave2);
 175 }
 176
 177
 178 void MapgenV7Params::writeParams(Settings *settings) const
 179 {
 180         settings->setFlagStr("mgv7_spflags",           spflags, flagdesc_mapgen_v7, U32_MAX);
 181         settings->setFloat("mgv7_cave_width",          cave_width);
 182         settings->setS16("mgv7_large_cave_depth",      large_cave_depth);
 183         settings->setS16("mgv7_lava_depth",            lava_depth);
 184         settings->setFloat("mgv7_float_mount_density", float_mount_density);
 185         settings->setFloat("mgv7_float_mount_height",  float_mount_height);
 186         settings->setS16("mgv7_floatland_level",       floatland_level);
 187         settings->setS16("mgv7_shadow_limit",          shadow_limit);
 188         settings->setS16("mgv7_cavern_limit",          cavern_limit);
 189         settings->setS16("mgv7_cavern_taper",          cavern_taper);
 190         settings->setFloat("mgv7_cavern_threshold",    cavern_threshold);
 191
 192         settings->setNoiseParams("mgv7_np_terrain_base",      np_terrain_base);
 193         settings->setNoiseParams("mgv7_np_terrain_alt",       np_terrain_alt);
 194         settings->setNoiseParams("mgv7_np_terrain_persist",   np_terrain_persist);
 195         settings->setNoiseParams("mgv7_np_height_select",     np_height_select);
 196         settings->setNoiseParams("mgv7_np_filler_depth",      np_filler_depth);
 197         settings->setNoiseParams("mgv7_np_mount_height",      np_mount_height);
 198         settings->setNoiseParams("mgv7_np_ridge_uwater",      np_ridge_uwater);
 199         settings->setNoiseParams("mgv7_np_floatland_base",    np_floatland_base);
 200         settings->setNoiseParams("mgv7_np_float_base_height", np_float_base_height);
 201         settings->setNoiseParams("mgv7_np_mountain",          np_mountain);
 202         settings->setNoiseParams("mgv7_np_ridge",             np_ridge);
 203         settings->setNoiseParams("mgv7_np_cavern",            np_cavern);
 204         settings->setNoiseParams("mgv7_np_cave1",             np_cave1);
 205         settings->setNoiseParams("mgv7_np_cave2",             np_cave2);
 206 }
 207
 208
 209 ///////////////////////////////////////////////////////////////////////////////
 210
 211
 212 int MapgenV7::getSpawnLevelAtPoint(v2s16 p)
 213 {
 214         // If rivers are enabled, first check if in a river
 215         if (spflags & MGV7_RIDGES) {
 216                 float width = 0.2;
 217                 float uwatern = NoisePerlin2D(&noise_ridge_uwater->np, p.X, p.Y, seed) * 2;
 218                 if (fabs(uwatern) <= width)
 219                         return MAX_MAP_GENERATION_LIMIT;  // Unsuitable spawn point
 220         }
 221
 222         // Terrain noise 'offset' is the average level of that terrain.
 223         // At least 50% of terrain will be below the higher of base and alt terrain
 224         // 'offset's.
 225         // Raising the maximum spawn level above 'water_level + 16' is necessary
 226         // for when terrain 'offset's are set much higher than water_level.
 227         s16 max_spawn_y = MYMAX(MYMAX(noise_terrain_alt->np.offset,
 228                         noise_terrain_base->np.offset),
 229                         water_level + 16);
 230         // Base terrain calculation
 231         s16 y = baseTerrainLevelAtPoint(p.X, p.Y);
 232
 233         // If mountains are disabled, terrain level is base terrain level.
 234         // Avoids mid-air spawn where mountain terrain would have been.
 235         if (!(spflags & MGV7_MOUNTAINS)) {
 236                 if (y <= water_level || y > max_spawn_y)
 237                         return MAX_MAP_GENERATION_LIMIT;  // Unsuitable spawn point
 238                 else
 239                         // + 1 to not be half-buried in a potential node-deep biome 'dust'
 240                         return y + 1;
 241         }
 242
 243         // Search upwards for first node without mountain terrain
 244         int iters = 256;
 245         while (iters > 0 && y <= max_spawn_y) {
 246                 if (!getMountainTerrainAtPoint(p.X, y + 1, p.Y)) {  // If air above
 247                         if (y <= water_level || y > max_spawn_y)
 248                                 return MAX_MAP_GENERATION_LIMIT;  // Unsuitable spawn point
 249                         else
 250                                 return y + 1;
 251                 }
 252                 y++;
 253                 iters--;
 254         }
 255
 256         // Unsuitable spawn point
 257         return MAX_MAP_GENERATION_LIMIT;
 258 }
 259
 260
 261 void MapgenV7::makeChunk(BlockMakeData *data)
 262 {
 263         // Pre-conditions
 264         assert(data->vmanip);
 265         assert(data->nodedef);
 266         assert(data->blockpos_requested.X >= data->blockpos_min.X &&
 267                 data->blockpos_requested.Y >= data->blockpos_min.Y &&
 268                 data->blockpos_requested.Z >= data->blockpos_min.Z);
 269         assert(data->blockpos_requested.X <= data->blockpos_max.X &&
 270                 data->blockpos_requested.Y <= data->blockpos_max.Y &&
 271                 data->blockpos_requested.Z <= data->blockpos_max.Z);
 272
 273         this->generating = true;
 274         this->vm   = data->vmanip;
 275         this->ndef = data->nodedef;
 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 base and mountain terrain
 288         // An initial heightmap is no longer created here for use in generateRidgeTerrain()
 289         s16 stone_surface_max_y = generateTerrain();
 290
 291         // Generate rivers
 292         if (spflags & MGV7_RIDGES)
 293                 generateRidgeTerrain();
 294
 295         // Create heightmap
 296         updateHeightmap(node_min, node_max);
 297
 298         // Init biome generator, place biome-specific nodes, and build biomemap
 299         biomegen->calcBiomeNoise(node_min);
 300         MgStoneType stone_type = generateBiomes();
 301
 302         // Generate caverns, tunnels and classic caves
 303         if (flags & MG_CAVES) {
 304                 bool near_cavern = false;
 305                 // Generate caverns
 306                 if (spflags & MGV7_CAVERNS)
 307                         near_cavern = generateCaverns(stone_surface_max_y);
 308                 // Generate tunnels and classic caves
 309                 if (near_cavern)
 310                         // Disable classic caves in this mapchunk by setting
 311                         // 'large cave depth' to world base. Avoids excessive liquid in
 312                         // large caverns and floating blobs of overgenerated liquid.
 313                         generateCaves(stone_surface_max_y, -MAX_MAP_GENERATION_LIMIT);
 314                 else
 315                         generateCaves(stone_surface_max_y, large_cave_depth);
 316         }
 317
 318         // Generate dungeons
 319         if (flags & MG_DUNGEONS)
 320                 generateDungeons(stone_surface_max_y, stone_type);
 321
 322         // Generate the registered decorations
 323         if (flags & MG_DECORATIONS)
 324                 m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
 325
 326         // Generate the registered ores
 327         m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max);
 328
 329         // Sprinkle some dust on top after everything else was generated
 330         dustTopNodes();
 331
 332         //printf("makeChunk: %dms\n", t.stop());
 333
 334         // Update liquids
 335         updateLiquid(&data->transforming_liquid, full_node_min, full_node_max);
 336
 337         // Calculate lighting
 338         // Limit floatland shadow
 339         bool propagate_shadow = !((spflags & MGV7_FLOATLANDS) &&
 340                 node_min.Y <= shadow_limit && node_max.Y >= shadow_limit);
 341
 342         if (flags & MG_LIGHT)
 343                 calcLighting(node_min - v3s16(0, 1, 0), node_max + v3s16(0, 1, 0),
 344                         full_node_min, full_node_max, propagate_shadow);
 345
 346         //setLighting(node_min - v3s16(1, 0, 1) * MAP_BLOCKSIZE,
 347         //                      node_max + v3s16(1, 0, 1) * MAP_BLOCKSIZE, 0xFF);
 348
 349         this->generating = false;
 350 }
 351
 352
 353 float MapgenV7::baseTerrainLevelAtPoint(s16 x, s16 z)
 354 {
 355         float hselect = NoisePerlin2D(&noise_height_select->np, x, z, seed);
 356         hselect = rangelim(hselect, 0.0, 1.0);
 357
 358         float persist = NoisePerlin2D(&noise_terrain_persist->np, x, z, seed);
 359
 360         noise_terrain_base->np.persist = persist;
 361         float height_base = NoisePerlin2D(&noise_terrain_base->np, x, z, seed);
 362
 363         noise_terrain_alt->np.persist = persist;
 364         float height_alt = NoisePerlin2D(&noise_terrain_alt->np, x, z, seed);
 365
 366         if (height_alt > height_base)
 367                 return height_alt;
 368
 369         return (height_base * hselect) + (height_alt * (1.0 - hselect));
 370 }
 371
 372
 373 float MapgenV7::baseTerrainLevelFromMap(int index)
 374 {
 375         float hselect     = rangelim(noise_height_select->result[index], 0.0, 1.0);
 376         float height_base = noise_terrain_base->result[index];
 377         float height_alt  = noise_terrain_alt->result[index];
 378
 379         if (height_alt > height_base)
 380                 return height_alt;
 381
 382         return (height_base * hselect) + (height_alt * (1.0 - hselect));
 383 }
 384
 385
 386 bool MapgenV7::getMountainTerrainAtPoint(s16 x, s16 y, s16 z)
 387 {
 388         float mnt_h_n =
 389                         MYMAX(NoisePerlin2D(&noise_mount_height->np, x, z, seed), 1.0f);
 390         float density_gradient = -((float)y / mnt_h_n);
 391         float mnt_n = NoisePerlin3D(&noise_mountain->np, x, y, z, seed);
 392
 393         return mnt_n + density_gradient >= 0.0;
 394 }
 395
 396
 397 bool MapgenV7::getMountainTerrainFromMap(int idx_xyz, int idx_xz, s16 y)
 398 {
 399         float mounthn = MYMAX(noise_mount_height->result[idx_xz], 1.0f);
 400         float density_gradient = -((float)y / mounthn);
 401         float mountn = noise_mountain->result[idx_xyz];
 402
 403         return mountn + density_gradient >= 0.0;
 404 }
 405
 406
 407 bool MapgenV7::getFloatlandMountainFromMap(int idx_xyz, int idx_xz, s16 y)
 408 {
 409         // Make rim 2 nodes thick to match floatland base terrain
 410         float density_gradient = (y >= floatland_level) ?
 411                 -pow((float)(y - floatland_level) / float_mount_height, 0.75f) :
 412                 -pow((float)(floatland_level - 1 - y) / float_mount_height, 0.75f);
 413
 414         float floatn = noise_mountain->result[idx_xyz] + float_mount_density;
 415
 416         return floatn + density_gradient >= 0.0f;
 417 }
 418
 419
 420 void MapgenV7::floatBaseExtentFromMap(s16 *float_base_min, s16 *float_base_max, int idx_xz)
 421 {
 422         // '+1' to avoid a layer of stone at y = MAX_MAP_GENERATION_LIMIT
 423         s16 base_min = MAX_MAP_GENERATION_LIMIT + 1;
 424         s16 base_max = MAX_MAP_GENERATION_LIMIT;
 425
 426         float n_base = noise_floatland_base->result[idx_xz];
 427         if (n_base > 0.0f) {
 428                 float n_base_height =
 429                                 MYMAX(noise_float_base_height->result[idx_xz], 1.0f);
 430                 float amp = n_base * n_base_height;
 431                 float ridge = n_base_height / 3.0f;
 432                 base_min = floatland_level - amp / 1.5f;
 433
 434                 if (amp > ridge * 2.0f) {
 435                         // Lake bed
 436                         base_max = floatland_level - (amp - ridge * 2.0f) / 2.0f;
 437                 } else {
 438                         // Hills and ridges
 439                         float diff = fabs(amp - ridge) / ridge;
 440                         // Smooth ridges using the 'smoothstep function'
 441                         float smooth_diff = diff * diff * (3.0f - 2.0f * diff);
 442                         base_max = floatland_level + ridge - smooth_diff * ridge;
 443                 }
 444         }
 445
 446         *float_base_min = base_min;
 447         *float_base_max = base_max;
 448 }
 449
 450
 451 int MapgenV7::generateTerrain()
 452 {
 453         MapNode n_air(CONTENT_AIR);
 454         MapNode n_stone(c_stone);
 455         MapNode n_water(c_water_source);
 456
 457         //// Calculate noise for terrain generation
 458         noise_terrain_persist->perlinMap2D(node_min.X, node_min.Z);
 459         float *persistmap = noise_terrain_persist->result;
 460
 461         noise_terrain_base->perlinMap2D(node_min.X, node_min.Z, persistmap);
 462         noise_terrain_alt->perlinMap2D(node_min.X, node_min.Z, persistmap);
 463         noise_height_select->perlinMap2D(node_min.X, node_min.Z);
 464
 465         if ((spflags & MGV7_MOUNTAINS) || (spflags & MGV7_FLOATLANDS)) {
 466                 noise_mountain->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
 467         }
 468
 469         if (spflags & MGV7_MOUNTAINS) {
 470                 noise_mount_height->perlinMap2D(node_min.X, node_min.Z);
 471         }
 472
 473         if (spflags & MGV7_FLOATLANDS) {
 474                 noise_floatland_base->perlinMap2D(node_min.X, node_min.Z);
 475                 noise_float_base_height->perlinMap2D(node_min.X, node_min.Z);
 476         }
 477
 478         //// Place nodes
 479         v3s16 em = vm->m_area.getExtent();
 480         s16 stone_surface_max_y = -MAX_MAP_GENERATION_LIMIT;
 481         u32 index2d = 0;
 482
 483         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 484         for (s16 x = node_min.X; x <= node_max.X; x++, index2d++) {
 485                 s16 surface_y = baseTerrainLevelFromMap(index2d);
 486                 if (surface_y > stone_surface_max_y)
 487                         stone_surface_max_y = surface_y;
 488
 489                 // Get extent of floatland base terrain
 490                 // '+1' to avoid a layer of stone at y = MAX_MAP_GENERATION_LIMIT
 491                 s16 float_base_min = MAX_MAP_GENERATION_LIMIT + 1;
 492                 s16 float_base_max = MAX_MAP_GENERATION_LIMIT;
 493                 if (spflags & MGV7_FLOATLANDS)
 494                         floatBaseExtentFromMap(&float_base_min, &float_base_max, index2d);
 495
 496                 u32 vi = vm->m_area.index(x, node_min.Y - 1, z);
 497                 u32 index3d = (z - node_min.Z) * zstride_1u1d + (x - node_min.X);
 498
 499                 for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
 500                         if (vm->m_data[vi].getContent() == CONTENT_IGNORE) {
 501                                 if (y <= surface_y) {
 502                                         vm->m_data[vi] = n_stone;  // Base terrain
 503                                 } else if ((spflags & MGV7_MOUNTAINS) &&
 504                                                 getMountainTerrainFromMap(index3d, index2d, y)) {
 505                                         vm->m_data[vi] = n_stone;  // Mountain terrain
 506                                         if (y > stone_surface_max_y)
 507                                                 stone_surface_max_y = y;
 508                                 } else if ((spflags & MGV7_FLOATLANDS) &&
 509                                                 ((y >= float_base_min && y <= float_base_max) ||
 510                                                 getFloatlandMountainFromMap(index3d, index2d, y))) {
 511                                         vm->m_data[vi] = n_stone;  // Floatland terrain
 512                                         stone_surface_max_y = node_max.Y;
 513                                 } else if (y <= water_level) {
 514                                         vm->m_data[vi] = n_water;  // Ground level water
 515                                 } else if ((spflags & MGV7_FLOATLANDS) &&
 516                                                 (y >= float_base_max && y <= floatland_level)) {
 517                                         vm->m_data[vi] = n_water;  // Floatland water
 518                                 } else {
 519                                         vm->m_data[vi] = n_air;
 520                                 }
 521                         }
 522                         vm->m_area.add_y(em, vi, 1);
 523                         index3d += ystride;
 524                 }
 525         }
 526
 527         return stone_surface_max_y;
 528 }
 529
 530
 531 void MapgenV7::generateRidgeTerrain()
 532 {
 533         if (node_max.Y < water_level - 16 ||
 534                         ((spflags & MGV7_FLOATLANDS) && node_max.Y > shadow_limit))
 535                 return;
 536
 537         noise_ridge->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
 538         noise_ridge_uwater->perlinMap2D(node_min.X, node_min.Z);
 539
 540         MapNode n_water(c_water_source);
 541         MapNode n_air(CONTENT_AIR);
 542         u32 index = 0;
 543         float width = 0.2;
 544
 545         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 546         for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
 547                 u32 vi = vm->m_area.index(node_min.X, y, z);
 548                 for (s16 x = node_min.X; x <= node_max.X; x++, index++, vi++) {
 549                         int j = (z - node_min.Z) * csize.X + (x - node_min.X);
 550
 551                         float uwatern = noise_ridge_uwater->result[j] * 2;
 552                         if (fabs(uwatern) > width)
 553                                 continue;
 554
 555                         float altitude = y - water_level;
 556                         float height_mod = (altitude + 17) / 2.5;
 557                         float width_mod  = width - fabs(uwatern);
 558                         float nridge = noise_ridge->result[index] * MYMAX(altitude, 0) / 7.0;
 559
 560                         if (nridge + width_mod * height_mod < 0.6)
 561                                 continue;
 562
 563                         vm->m_data[vi] = (y > water_level) ? n_air : n_water;
 564                 }
 565         }
 566 }
 567
 568
 569 ////////////////////////////////////////////////////////////////////////////////
 570 //// Code Boneyard
 571 ////
 572 //// Much of the stuff here has potential to become useful again at some point
 573 //// in the future, but we don't want it to get lost or forgotten in version
 574 //// control.
 575 ////
 576
 577 #if 0
 578 int MapgenV7::generateMountainTerrain(s16 ymax)
 579 {
 580         MapNode n_stone(c_stone);
 581         u32 j = 0;
 582
 583         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 584         for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
 585                 u32 vi = vm->m_area.index(node_min.X, y, z);
 586                 for (s16 x = node_min.X; x <= node_max.X; x++) {
 587                         int index = (z - node_min.Z) * csize.X + (x - node_min.X);
 588                         content_t c = vm->m_data[vi].getContent();
 589
 590                         if (getMountainTerrainFromMap(j, index, y)
 591                                         && (c == CONTENT_AIR || c == c_water_source)) {
 592                                 vm->m_data[vi] = n_stone;
 593                                 if (y > ymax)
 594                                         ymax = y;
 595                         }
 596
 597                         vi++;
 598                         j++;
 599                 }
 600         }
 601
 602         return ymax;
 603 }
 604 #endif
 605
 606
 607 #if 0
 608 void MapgenV7::carveRivers() {
 609         MapNode n_air(CONTENT_AIR), n_water_source(c_water_source);
 610         MapNode n_stone(c_stone);
 611         u32 index = 0;
 612
 613         int river_depth = 4;
 614
 615         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 616         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
 617                 float terrain_mod  = noise_terrain_mod->result[index];
 618                 NoiseParams *np = noise_terrain_river->np;
 619                 np.persist = noise_terrain_persist->result[index];
 620                 float terrain_river = NoisePerlin2DNoTxfm(np, x, z, seed);
 621                 float height = terrain_river * (1 - abs(terrain_mod)) *
 622                                                 noise_terrain_river->np.scale;
 623                 height = log(height * height); //log(h^3) is pretty interesting for terrain
 624
 625                 s16 y = heightmap[index];
 626                 if (height < 1.0 && y > river_depth &&
 627                         y - river_depth >= node_min.Y && y <= node_max.Y) {
 628
 629                         for (s16 ry = y; ry != y - river_depth; ry--) {
 630                                 u32 vi = vm->m_area.index(x, ry, z);
 631                                 vm->m_data[vi] = n_air;
 632                         }
 633
 634                         u32 vi = vm->m_area.index(x, y - river_depth, z);
 635                         vm->m_data[vi] = n_water_source;
 636                 }
 637         }
 638 }
 639 #endif
 640
 641
 642 #if 0
 643 void MapgenV7::addTopNodes()
 644 {
 645         v3s16 em = vm->m_area.getExtent();
 646         s16 ntopnodes;
 647         u32 index = 0;
 648
 649         for (s16 z = node_min.Z; z <= node_max.Z; z++)
 650         for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
 651                 Biome *biome = bmgr->biomes[biomemap[index]];
 652
 653                 //////////////////// First, add top nodes below the ridge
 654                 s16 y = ridge_heightmap[index];
 655
 656                 // This cutoff is good enough, but not perfect.
 657                 // It will cut off potentially placed top nodes at chunk boundaries
 658                 if (y < node_min.Y)
 659                         continue;
 660                 if (y > node_max.Y) {
 661                         y = node_max.Y; // Let's see if we can still go downward anyway
 662                         u32 vi = vm->m_area.index(x, y, z);
 663                         content_t c = vm->m_data[vi].getContent();
 664                         if (ndef->get(c).walkable)
 665                                 continue;
 666                 }
 667
 668                 // N.B.  It is necessary to search downward since ridge_heightmap[i]
 669                 // might not be the actual height, just the lowest part in the chunk
 670                 // where a ridge had been carved
 671                 u32 i = vm->m_area.index(x, y, z);
 672                 for (; y >= node_min.Y; y--) {
 673                         content_t c = vm->m_data[i].getContent();
 674                         if (ndef->get(c).walkable)
 675                                 break;
 676                         vm->m_area.add_y(em, i, -1);
 677                 }
 678
 679                 if (y != node_min.Y - 1 && y >= water_level) {
 680                         ridge_heightmap[index] = y; //update ridgeheight
 681                         ntopnodes = biome->top_depth;
 682                         for (; y <= node_max.Y && ntopnodes; y++) {
 683                                 ntopnodes--;
 684                                 vm->m_data[i] = MapNode(biome->c_top);
 685                                 vm->m_area.add_y(em, i, 1);
 686                         }
 687                         // If dirt, grow grass on it.
 688                         if (y > water_level - 10 &&
 689                                 vm->m_data[i].getContent() == CONTENT_AIR) {
 690                                 vm->m_area.add_y(em, i, -1);
 691                                 if (vm->m_data[i].getContent() == c_dirt)
 692                                         vm->m_data[i] = MapNode(c_dirt_with_grass);
 693                         }
 694                 }
 695
 696                 //////////////////// Now, add top nodes on top of the ridge
 697                 y = heightmap[index];
 698                 if (y > node_max.Y) {
 699                         y = node_max.Y; // Let's see if we can still go downward anyway
 700                         u32 vi = vm->m_area.index(x, y, z);
 701                         content_t c = vm->m_data[vi].getContent();
 702                         if (ndef->get(c).walkable)
 703                                 continue;
 704                 }
 705
 706                 i = vm->m_area.index(x, y, z);
 707                 for (; y >= node_min.Y; y--) {
 708                         content_t c = vm->m_data[i].getContent();
 709                         if (ndef->get(c).walkable)
 710                                 break;
 711                         vm->m_area.add_y(em, i, -1);
 712                 }
 713
 714                 if (y != node_min.Y - 1) {
 715                         ntopnodes = biome->top_depth;
 716                         // Let's see if we've already added it...
 717                         if (y == ridge_heightmap[index] + ntopnodes - 1)
 718                                 continue;
 719
 720                         for (; y <= node_max.Y && ntopnodes; y++) {
 721                                 ntopnodes--;
 722                                 vm->m_data[i] = MapNode(biome->c_top);
 723                                 vm->m_area.add_y(em, i, 1);
 724                         }
 725                         // If dirt, grow grass on it.
 726                         if (y > water_level - 10 &&
 727                                 vm->m_data[i].getContent() == CONTENT_AIR) {
 728                                 vm->m_area.add_y(em, i, -1);
 729                                 if (vm->m_data[i].getContent() == c_dirt)
 730                                         vm->m_data[i] = MapNode(c_dirt_with_grass);
 731                         }
 732                 }
 733         }
 734 }
 735 #endif