Fix various clang-tidy reported performance-type-promotion-in-math-fn
[oweals/minetest.git] / src / mapgen / mapgen_v7.cpp
1 /*
2 Minetest
3 Copyright (C) 2013-2018 kwolekr, Ryan Kwolek <kwolekr@minetest.net>
4 Copyright (C) 2014-2018 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 <cmath>
24 #include "voxel.h"
25 #include "noise.h"
26 #include "mapblock.h"
27 #include "mapnode.h"
28 #include "map.h"
29 #include "content_sao.h"
30 #include "nodedef.h"
31 #include "voxelalgorithms.h"
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         spflags              = params->spflags;
58         mount_zero_level     = params->mount_zero_level;
59         cave_width           = params->cave_width;
60         large_cave_depth     = params->large_cave_depth;
61         lava_depth           = params->lava_depth;
62         float_mount_density  = params->float_mount_density;
63         float_mount_exponent = params->float_mount_exponent;
64         floatland_level      = params->floatland_level;
65         shadow_limit         = params->shadow_limit;
66         cavern_limit         = params->cavern_limit;
67         cavern_taper         = params->cavern_taper;
68         cavern_threshold     = params->cavern_threshold;
69         dungeon_ymin         = params->dungeon_ymin;
70         dungeon_ymax         = params->dungeon_ymax;
71
72         // This is to avoid a divide-by-zero.
73         // Parameter will be saved to map_meta.txt in limited form.
74         params->float_mount_height = MYMAX(params->float_mount_height, 1.0f);
75         float_mount_height   = params->float_mount_height;
76
77         // 2D noise
78         noise_terrain_base    = new Noise(&params->np_terrain_base,    seed, csize.X, csize.Z);
79         noise_terrain_alt     = new Noise(&params->np_terrain_alt,     seed, csize.X, csize.Z);
80         noise_terrain_persist = new Noise(&params->np_terrain_persist, seed, csize.X, csize.Z);
81         noise_height_select   = new Noise(&params->np_height_select,   seed, csize.X, csize.Z);
82         noise_filler_depth    = new Noise(&params->np_filler_depth,    seed, csize.X, csize.Z);
83
84         if (spflags & MGV7_MOUNTAINS)
85                 noise_mount_height = new Noise(&params->np_mount_height, seed, csize.X, csize.Z);
86
87         if (spflags & MGV7_FLOATLANDS) {
88                 noise_floatland_base    = new Noise(&params->np_floatland_base,    seed, csize.X, csize.Z);
89                 noise_float_base_height = new Noise(&params->np_float_base_height, seed, csize.X, csize.Z);
90         }
91
92         if (spflags & MGV7_RIDGES) {
93                 noise_ridge_uwater = new Noise(&params->np_ridge_uwater, seed, csize.X, csize.Z);
94         // 3D noise, 1-up 1-down overgeneration
95                 noise_ridge = new Noise(&params->np_ridge, seed, csize.X, csize.Y + 2, csize.Z);
96         }
97         // 3D noise, 1 up, 1 down overgeneration
98         if ((spflags & MGV7_MOUNTAINS) || (spflags & MGV7_FLOATLANDS))
99                 noise_mountain = new Noise(&params->np_mountain, seed, csize.X, csize.Y + 2, csize.Z);
100         // 3D noise, 1 down overgeneration
101         MapgenBasic::np_cave1  = params->np_cave1;
102         MapgenBasic::np_cave2  = params->np_cave2;
103         MapgenBasic::np_cavern = params->np_cavern;
104 }
105
106
107 MapgenV7::~MapgenV7()
108 {
109         delete noise_terrain_base;
110         delete noise_terrain_alt;
111         delete noise_terrain_persist;
112         delete noise_height_select;
113         delete noise_filler_depth;
114
115         if (spflags & MGV7_MOUNTAINS)
116                 delete noise_mount_height;
117
118         if (spflags & MGV7_FLOATLANDS) {
119                 delete noise_floatland_base;
120                 delete noise_float_base_height;
121         }
122
123         if (spflags & MGV7_RIDGES) {
124                 delete noise_ridge_uwater;
125                 delete noise_ridge;
126         }
127
128         if ((spflags & MGV7_MOUNTAINS) || (spflags & MGV7_FLOATLANDS))
129                 delete noise_mountain;
130 }
131
132
133 MapgenV7Params::MapgenV7Params():
134         np_terrain_base      (4,    70,   v3f(600,  600,  600),  82341, 5, 0.6,  2.0),
135         np_terrain_alt       (4,    25,   v3f(600,  600,  600),  5934,  5, 0.6,  2.0),
136         np_terrain_persist   (0.6,  0.1,  v3f(2000, 2000, 2000), 539,   3, 0.6,  2.0),
137         np_height_select     (-8,   16,   v3f(500,  500,  500),  4213,  6, 0.7,  2.0),
138         np_filler_depth      (0,    1.2,  v3f(150,  150,  150),  261,   3, 0.7,  2.0),
139         np_mount_height      (256,  112,  v3f(1000, 1000, 1000), 72449, 3, 0.6,  2.0),
140         np_ridge_uwater      (0,    1,    v3f(1000, 1000, 1000), 85039, 5, 0.6,  2.0),
141         np_floatland_base    (-0.6, 1.5,  v3f(600,  600,  600),  114,   5, 0.6,  2.0),
142         np_float_base_height (48,   24,   v3f(300,  300,  300),  907,   4, 0.7,  2.0),
143         np_mountain          (-0.6, 1,    v3f(250,  350,  250),  5333,  5, 0.63, 2.0),
144         np_ridge             (0,    1,    v3f(100,  100,  100),  6467,  4, 0.75, 2.0),
145         np_cavern            (0,    1,    v3f(384,  128,  384),  723,   5, 0.63, 2.0),
146         np_cave1             (0,    12,   v3f(61,   61,   61),   52534, 3, 0.5,  2.0),
147         np_cave2             (0,    12,   v3f(67,   67,   67),   10325, 3, 0.5,  2.0)
148 {
149 }
150
151
152 void MapgenV7Params::readParams(const Settings *settings)
153 {
154         settings->getFlagStrNoEx("mgv7_spflags",            spflags, flagdesc_mapgen_v7);
155         settings->getS16NoEx("mgv7_mount_zero_level",       mount_zero_level);
156         settings->getFloatNoEx("mgv7_cave_width",           cave_width);
157         settings->getS16NoEx("mgv7_large_cave_depth",       large_cave_depth);
158         settings->getS16NoEx("mgv7_lava_depth",             lava_depth);
159         settings->getFloatNoEx("mgv7_float_mount_density",  float_mount_density);
160         settings->getFloatNoEx("mgv7_float_mount_height",   float_mount_height);
161         settings->getFloatNoEx("mgv7_float_mount_exponent", float_mount_exponent);
162         settings->getS16NoEx("mgv7_floatland_level",        floatland_level);
163         settings->getS16NoEx("mgv7_shadow_limit",           shadow_limit);
164         settings->getS16NoEx("mgv7_cavern_limit",           cavern_limit);
165         settings->getS16NoEx("mgv7_cavern_taper",           cavern_taper);
166         settings->getFloatNoEx("mgv7_cavern_threshold",     cavern_threshold);
167         settings->getS16NoEx("mgv7_dungeon_ymin",           dungeon_ymin);
168         settings->getS16NoEx("mgv7_dungeon_ymax",           dungeon_ymax);
169
170         settings->getNoiseParams("mgv7_np_terrain_base",      np_terrain_base);
171         settings->getNoiseParams("mgv7_np_terrain_alt",       np_terrain_alt);
172         settings->getNoiseParams("mgv7_np_terrain_persist",   np_terrain_persist);
173         settings->getNoiseParams("mgv7_np_height_select",     np_height_select);
174         settings->getNoiseParams("mgv7_np_filler_depth",      np_filler_depth);
175         settings->getNoiseParams("mgv7_np_mount_height",      np_mount_height);
176         settings->getNoiseParams("mgv7_np_ridge_uwater",      np_ridge_uwater);
177         settings->getNoiseParams("mgv7_np_floatland_base",    np_floatland_base);
178         settings->getNoiseParams("mgv7_np_float_base_height", np_float_base_height);
179         settings->getNoiseParams("mgv7_np_mountain",          np_mountain);
180         settings->getNoiseParams("mgv7_np_ridge",             np_ridge);
181         settings->getNoiseParams("mgv7_np_cavern",            np_cavern);
182         settings->getNoiseParams("mgv7_np_cave1",             np_cave1);
183         settings->getNoiseParams("mgv7_np_cave2",             np_cave2);
184 }
185
186
187 void MapgenV7Params::writeParams(Settings *settings) const
188 {
189         settings->setFlagStr("mgv7_spflags",            spflags, flagdesc_mapgen_v7, U32_MAX);
190         settings->setS16("mgv7_mount_zero_level",       mount_zero_level);
191         settings->setFloat("mgv7_cave_width",           cave_width);
192         settings->setS16("mgv7_large_cave_depth",       large_cave_depth);
193         settings->setS16("mgv7_lava_depth",             lava_depth);
194         settings->setFloat("mgv7_float_mount_density",  float_mount_density);
195         settings->setFloat("mgv7_float_mount_height",   float_mount_height);
196         settings->setFloat("mgv7_float_mount_exponent", float_mount_exponent);
197         settings->setS16("mgv7_floatland_level",        floatland_level);
198         settings->setS16("mgv7_shadow_limit",           shadow_limit);
199         settings->setS16("mgv7_cavern_limit",           cavern_limit);
200         settings->setS16("mgv7_cavern_taper",           cavern_taper);
201         settings->setFloat("mgv7_cavern_threshold",     cavern_threshold);
202         settings->setS16("mgv7_dungeon_ymin",           dungeon_ymin);
203         settings->setS16("mgv7_dungeon_ymax",           dungeon_ymax);
204
205         settings->setNoiseParams("mgv7_np_terrain_base",      np_terrain_base);
206         settings->setNoiseParams("mgv7_np_terrain_alt",       np_terrain_alt);
207         settings->setNoiseParams("mgv7_np_terrain_persist",   np_terrain_persist);
208         settings->setNoiseParams("mgv7_np_height_select",     np_height_select);
209         settings->setNoiseParams("mgv7_np_filler_depth",      np_filler_depth);
210         settings->setNoiseParams("mgv7_np_mount_height",      np_mount_height);
211         settings->setNoiseParams("mgv7_np_ridge_uwater",      np_ridge_uwater);
212         settings->setNoiseParams("mgv7_np_floatland_base",    np_floatland_base);
213         settings->setNoiseParams("mgv7_np_float_base_height", np_float_base_height);
214         settings->setNoiseParams("mgv7_np_mountain",          np_mountain);
215         settings->setNoiseParams("mgv7_np_ridge",             np_ridge);
216         settings->setNoiseParams("mgv7_np_cavern",            np_cavern);
217         settings->setNoiseParams("mgv7_np_cave1",             np_cave1);
218         settings->setNoiseParams("mgv7_np_cave2",             np_cave2);
219 }
220
221
222 ///////////////////////////////////////////////////////////////////////////////
223
224
225 int MapgenV7::getSpawnLevelAtPoint(v2s16 p)
226 {
227         // If rivers are enabled, first check if in a river
228         if (spflags & MGV7_RIDGES) {
229                 float width = 0.2;
230                 float uwatern = NoisePerlin2D(&noise_ridge_uwater->np, p.X, p.Y, seed) * 2;
231                 if (std::fabs(uwatern) <= width)
232                         return MAX_MAP_GENERATION_LIMIT;  // Unsuitable spawn point
233         }
234
235         // Terrain noise 'offset' is the average level of that terrain.
236         // At least 50% of terrain will be below the higher of base and alt terrain
237         // 'offset's.
238         // Raising the maximum spawn level above 'water_level + 16' is necessary
239         // for when terrain 'offset's are set much higher than water_level.
240         s16 max_spawn_y = MYMAX(MYMAX(noise_terrain_alt->np.offset,
241                         noise_terrain_base->np.offset),
242                         water_level + 16);
243         // Base terrain calculation
244         s16 y = baseTerrainLevelAtPoint(p.X, p.Y);
245
246         // If mountains are disabled, terrain level is base terrain level.
247         // Avoids mid-air spawn where mountain terrain would have been.
248         if (!(spflags & MGV7_MOUNTAINS)) {
249                 if (y < water_level || y > max_spawn_y)
250                         return MAX_MAP_GENERATION_LIMIT;  // Unsuitable spawn point
251
252                 // y + 2 because y is surface level and due to biome 'dust'
253                 return y + 2;
254         }
255
256         // Search upwards for first node without mountain terrain
257         int iters = 256;
258         while (iters > 0 && y <= max_spawn_y) {
259                 if (!getMountainTerrainAtPoint(p.X, y + 1, p.Y)) {
260                         if (y <= water_level || y > max_spawn_y)
261                                 return MAX_MAP_GENERATION_LIMIT;  // Unsuitable spawn point
262
263                         // y + 1 due to biome 'dust'
264                         return y + 1;
265                 }
266                 y++;
267                 iters--;
268         }
269
270         // Unsuitable spawn point
271         return MAX_MAP_GENERATION_LIMIT;
272 }
273
274
275 void MapgenV7::makeChunk(BlockMakeData *data)
276 {
277         // Pre-conditions
278         assert(data->vmanip);
279         assert(data->nodedef);
280         assert(data->blockpos_requested.X >= data->blockpos_min.X &&
281                 data->blockpos_requested.Y >= data->blockpos_min.Y &&
282                 data->blockpos_requested.Z >= data->blockpos_min.Z);
283         assert(data->blockpos_requested.X <= data->blockpos_max.X &&
284                 data->blockpos_requested.Y <= data->blockpos_max.Y &&
285                 data->blockpos_requested.Z <= data->blockpos_max.Z);
286
287         this->generating = true;
288         this->vm   = data->vmanip;
289         this->ndef = data->nodedef;
290         //TimeTaker t("makeChunk");
291
292         v3s16 blockpos_min = data->blockpos_min;
293         v3s16 blockpos_max = data->blockpos_max;
294         node_min = blockpos_min * MAP_BLOCKSIZE;
295         node_max = (blockpos_max + v3s16(1, 1, 1)) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
296         full_node_min = (blockpos_min - 1) * MAP_BLOCKSIZE;
297         full_node_max = (blockpos_max + 2) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
298
299         blockseed = getBlockSeed2(full_node_min, seed);
300
301         // Generate base and mountain terrain
302         // An initial heightmap is no longer created here for use in generateRidgeTerrain()
303         s16 stone_surface_max_y = generateTerrain();
304
305         // Generate rivers
306         if (spflags & MGV7_RIDGES)
307                 generateRidgeTerrain();
308
309         // Create heightmap
310         updateHeightmap(node_min, node_max);
311
312         // Init biome generator, place biome-specific nodes, and build biomemap
313         biomegen->calcBiomeNoise(node_min);
314
315         MgStoneType mgstone_type;
316         content_t biome_stone;
317         generateBiomes(&mgstone_type, &biome_stone);
318
319         // Generate caverns, tunnels and classic caves
320         if (flags & MG_CAVES) {
321                 bool near_cavern = false;
322                 // Generate caverns
323                 if (spflags & MGV7_CAVERNS)
324                         near_cavern = generateCaverns(stone_surface_max_y);
325                 // Generate tunnels and classic caves
326                 if (near_cavern)
327                         // Disable classic caves in this mapchunk by setting
328                         // 'large cave depth' to world base. Avoids excessive liquid in
329                         // large caverns and floating blobs of overgenerated liquid.
330                         generateCaves(stone_surface_max_y, -MAX_MAP_GENERATION_LIMIT);
331                 else
332                         generateCaves(stone_surface_max_y, large_cave_depth);
333         }
334
335         // Generate dungeons
336         if ((flags & MG_DUNGEONS) && full_node_min.Y >= dungeon_ymin &&
337                         full_node_max.Y <= dungeon_ymax)
338                 generateDungeons(stone_surface_max_y, mgstone_type, biome_stone);
339
340         // Generate the registered decorations
341         if (flags & MG_DECORATIONS)
342                 m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
343
344         // Generate the registered ores
345         m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max);
346
347         // Sprinkle some dust on top after everything else was generated
348         dustTopNodes();
349
350         //printf("makeChunk: %dms\n", t.stop());
351
352         // Update liquids
353         updateLiquid(&data->transforming_liquid, full_node_min, full_node_max);
354
355         // Calculate lighting
356         // Limit floatland shadow
357         bool propagate_shadow = !((spflags & MGV7_FLOATLANDS) &&
358                 node_min.Y <= shadow_limit && node_max.Y >= shadow_limit);
359
360         if (flags & MG_LIGHT)
361                 calcLighting(node_min - v3s16(0, 1, 0), node_max + v3s16(0, 1, 0),
362                         full_node_min, full_node_max, propagate_shadow);
363
364         //setLighting(node_min - v3s16(1, 0, 1) * MAP_BLOCKSIZE,
365         //                      node_max + v3s16(1, 0, 1) * MAP_BLOCKSIZE, 0xFF);
366
367         this->generating = false;
368 }
369
370
371 float MapgenV7::baseTerrainLevelAtPoint(s16 x, s16 z)
372 {
373         float hselect = NoisePerlin2D(&noise_height_select->np, x, z, seed);
374         hselect = rangelim(hselect, 0.0, 1.0);
375
376         float persist = NoisePerlin2D(&noise_terrain_persist->np, x, z, seed);
377
378         noise_terrain_base->np.persist = persist;
379         float height_base = NoisePerlin2D(&noise_terrain_base->np, x, z, seed);
380
381         noise_terrain_alt->np.persist = persist;
382         float height_alt = NoisePerlin2D(&noise_terrain_alt->np, x, z, seed);
383
384         if (height_alt > height_base)
385                 return height_alt;
386
387         return (height_base * hselect) + (height_alt * (1.0 - hselect));
388 }
389
390
391 float MapgenV7::baseTerrainLevelFromMap(int index)
392 {
393         float hselect     = rangelim(noise_height_select->result[index], 0.0, 1.0);
394         float height_base = noise_terrain_base->result[index];
395         float height_alt  = noise_terrain_alt->result[index];
396
397         if (height_alt > height_base)
398                 return height_alt;
399
400         return (height_base * hselect) + (height_alt * (1.0 - hselect));
401 }
402
403
404 bool MapgenV7::getMountainTerrainAtPoint(s16 x, s16 y, s16 z)
405 {
406         float mnt_h_n =
407                         MYMAX(NoisePerlin2D(&noise_mount_height->np, x, z, seed), 1.0f);
408         float density_gradient = -((float)(y - mount_zero_level) / mnt_h_n);
409         float mnt_n = NoisePerlin3D(&noise_mountain->np, x, y, z, seed);
410
411         return mnt_n + density_gradient >= 0.0;
412 }
413
414
415 bool MapgenV7::getMountainTerrainFromMap(int idx_xyz, int idx_xz, s16 y)
416 {
417         float mounthn = MYMAX(noise_mount_height->result[idx_xz], 1.0f);
418         float density_gradient = -((float)(y - mount_zero_level) / mounthn);
419         float mountn = noise_mountain->result[idx_xyz];
420
421         return mountn + density_gradient >= 0.0;
422 }
423
424
425 bool MapgenV7::getFloatlandMountainFromMap(int idx_xyz, int idx_xz, s16 y)
426 {
427         // Make rim 2 nodes thick to match floatland base terrain
428         float density_gradient = (y >= floatland_level) ?
429                 -std::pow((float)(y - floatland_level) / float_mount_height,
430                 float_mount_exponent) :
431                 -std::pow((float)(floatland_level - 1 - y) / float_mount_height,
432                 float_mount_exponent);
433
434         float floatn = noise_mountain->result[idx_xyz] + float_mount_density;
435
436         return floatn + density_gradient >= 0.0f;
437 }
438
439
440 void MapgenV7::floatBaseExtentFromMap(s16 *float_base_min, s16 *float_base_max, int idx_xz)
441 {
442         // '+1' to avoid a layer of stone at y = MAX_MAP_GENERATION_LIMIT
443         s16 base_min = MAX_MAP_GENERATION_LIMIT + 1;
444         s16 base_max = MAX_MAP_GENERATION_LIMIT;
445
446         float n_base = noise_floatland_base->result[idx_xz];
447         if (n_base > 0.0f) {
448                 float n_base_height =
449                                 MYMAX(noise_float_base_height->result[idx_xz], 1.0f);
450                 float amp = n_base * n_base_height;
451                 float ridge = n_base_height / 3.0f;
452                 base_min = floatland_level - amp / 1.5f;
453
454                 if (amp > ridge * 2.0f) {
455                         // Lake bed
456                         base_max = floatland_level - (amp - ridge * 2.0f) / 2.0f;
457                 } else {
458                         // Hills and ridges
459                         float diff = std::fabs(amp - ridge) / ridge;
460                         // Smooth ridges using the 'smoothstep function'
461                         float smooth_diff = diff * diff * (3.0f - 2.0f * diff);
462                         base_max = floatland_level + ridge - smooth_diff * ridge;
463                 }
464         }
465
466         *float_base_min = base_min;
467         *float_base_max = base_max;
468 }
469
470
471 int MapgenV7::generateTerrain()
472 {
473         MapNode n_air(CONTENT_AIR);
474         MapNode n_stone(c_stone);
475         MapNode n_water(c_water_source);
476
477         //// Calculate noise for terrain generation
478         noise_terrain_persist->perlinMap2D(node_min.X, node_min.Z);
479         float *persistmap = noise_terrain_persist->result;
480
481         noise_terrain_base->perlinMap2D(node_min.X, node_min.Z, persistmap);
482         noise_terrain_alt->perlinMap2D(node_min.X, node_min.Z, persistmap);
483         noise_height_select->perlinMap2D(node_min.X, node_min.Z);
484
485         if ((spflags & MGV7_MOUNTAINS) || (spflags & MGV7_FLOATLANDS)) {
486                 noise_mountain->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
487         }
488
489         if (spflags & MGV7_MOUNTAINS) {
490                 noise_mount_height->perlinMap2D(node_min.X, node_min.Z);
491         }
492
493         if (spflags & MGV7_FLOATLANDS) {
494                 noise_floatland_base->perlinMap2D(node_min.X, node_min.Z);
495                 noise_float_base_height->perlinMap2D(node_min.X, node_min.Z);
496         }
497
498         //// Place nodes
499         const v3s16 &em = vm->m_area.getExtent();
500         s16 stone_surface_max_y = -MAX_MAP_GENERATION_LIMIT;
501         u32 index2d = 0;
502
503         for (s16 z = node_min.Z; z <= node_max.Z; z++)
504         for (s16 x = node_min.X; x <= node_max.X; x++, index2d++) {
505                 s16 surface_y = baseTerrainLevelFromMap(index2d);
506                 if (surface_y > stone_surface_max_y)
507                         stone_surface_max_y = surface_y;
508
509                 // Get extent of floatland base terrain
510                 // '+1' to avoid a layer of stone at y = MAX_MAP_GENERATION_LIMIT
511                 s16 float_base_min = MAX_MAP_GENERATION_LIMIT + 1;
512                 s16 float_base_max = MAX_MAP_GENERATION_LIMIT;
513                 if (spflags & MGV7_FLOATLANDS)
514                         floatBaseExtentFromMap(&float_base_min, &float_base_max, index2d);
515
516                 u32 vi = vm->m_area.index(x, node_min.Y - 1, z);
517                 u32 index3d = (z - node_min.Z) * zstride_1u1d + (x - node_min.X);
518
519                 for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
520                         if (vm->m_data[vi].getContent() == CONTENT_IGNORE) {
521                                 if (y <= surface_y) {
522                                         vm->m_data[vi] = n_stone;  // Base terrain
523                                 } else if ((spflags & MGV7_MOUNTAINS) &&
524                                                 getMountainTerrainFromMap(index3d, index2d, y)) {
525                                         vm->m_data[vi] = n_stone;  // Mountain terrain
526                                         if (y > stone_surface_max_y)
527                                                 stone_surface_max_y = y;
528                                 } else if ((spflags & MGV7_FLOATLANDS) &&
529                                                 ((y >= float_base_min && y <= float_base_max) ||
530                                                 getFloatlandMountainFromMap(index3d, index2d, y))) {
531                                         vm->m_data[vi] = n_stone;  // Floatland terrain
532                                         stone_surface_max_y = node_max.Y;
533                                 } else if (y <= water_level) {
534                                         vm->m_data[vi] = n_water;  // Ground level water
535                                 } else if ((spflags & MGV7_FLOATLANDS) &&
536                                                 (y >= float_base_max && y <= floatland_level)) {
537                                         vm->m_data[vi] = n_water;  // Floatland water
538                                 } else {
539                                         vm->m_data[vi] = n_air;
540                                 }
541                         }
542                         VoxelArea::add_y(em, vi, 1);
543                         index3d += ystride;
544                 }
545         }
546
547         return stone_surface_max_y;
548 }
549
550
551 void MapgenV7::generateRidgeTerrain()
552 {
553         if (node_max.Y < water_level - 16 ||
554                         ((spflags & MGV7_FLOATLANDS) && node_max.Y > shadow_limit))
555                 return;
556
557         noise_ridge->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
558         noise_ridge_uwater->perlinMap2D(node_min.X, node_min.Z);
559
560         MapNode n_water(c_water_source);
561         MapNode n_air(CONTENT_AIR);
562         u32 index = 0;
563         float width = 0.2;
564
565         for (s16 z = node_min.Z; z <= node_max.Z; z++)
566         for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
567                 u32 vi = vm->m_area.index(node_min.X, y, z);
568                 for (s16 x = node_min.X; x <= node_max.X; x++, index++, vi++) {
569                         int j = (z - node_min.Z) * csize.X + (x - node_min.X);
570
571                         float uwatern = noise_ridge_uwater->result[j] * 2;
572                         if (std::fabs(uwatern) > width)
573                                 continue;
574
575                         float altitude = y - water_level;
576                         float height_mod = (altitude + 17) / 2.5;
577                         float width_mod  = width - std::fabs(uwatern);
578                         float nridge = noise_ridge->result[index] * MYMAX(altitude, 0) / 7.0;
579
580                         if (nridge + width_mod * height_mod < 0.6)
581                                 continue;
582
583                         vm->m_data[vi] = (y > water_level) ? n_air : n_water;
584                 }
585         }
586 }