Fix many issues reported by clang-tidy (#7189)
[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 "profiler.h" // For TimeTaker
33 #include "settings.h" // For g_settings
34 #include "emerge.h"
35 #include "dungeongen.h"
36 #include "cavegen.h"
37 #include "mg_biome.h"
38 #include "mg_ore.h"
39 #include "mg_decoration.h"
40 #include "mapgen_v7.h"
41
42
43 FlagDesc flagdesc_mapgen_v7[] = {
44         {"mountains",   MGV7_MOUNTAINS},
45         {"ridges",      MGV7_RIDGES},
46         {"floatlands",  MGV7_FLOATLANDS},
47         {"caverns",     MGV7_CAVERNS},
48         {NULL,          0}
49 };
50
51
52 ///////////////////////////////////////////////////////////////////////////////
53
54
55 MapgenV7::MapgenV7(int mapgenid, MapgenV7Params *params, EmergeManager *emerge)
56         : MapgenBasic(mapgenid, params, emerge)
57 {
58         spflags              = params->spflags;
59         mount_zero_level     = params->mount_zero_level;
60         cave_width           = params->cave_width;
61         large_cave_depth     = params->large_cave_depth;
62         lava_depth           = params->lava_depth;
63         float_mount_density  = params->float_mount_density;
64         float_mount_exponent = params->float_mount_exponent;
65         floatland_level      = params->floatland_level;
66         shadow_limit         = params->shadow_limit;
67         cavern_limit         = params->cavern_limit;
68         cavern_taper         = params->cavern_taper;
69         cavern_threshold     = params->cavern_threshold;
70         dungeon_ymin         = params->dungeon_ymin;
71         dungeon_ymax         = params->dungeon_ymax;
72
73         // This is to avoid a divide-by-zero.
74         // Parameter will be saved to map_meta.txt in limited form.
75         params->float_mount_height = MYMAX(params->float_mount_height, 1.0f);
76         float_mount_height   = params->float_mount_height;
77
78         // 2D noise
79         noise_terrain_base    = new Noise(&params->np_terrain_base,    seed, csize.X, csize.Z);
80         noise_terrain_alt     = new Noise(&params->np_terrain_alt,     seed, csize.X, csize.Z);
81         noise_terrain_persist = new Noise(&params->np_terrain_persist, seed, csize.X, csize.Z);
82         noise_height_select   = new Noise(&params->np_height_select,   seed, csize.X, csize.Z);
83         noise_filler_depth    = new Noise(&params->np_filler_depth,    seed, csize.X, csize.Z);
84
85         if (spflags & MGV7_MOUNTAINS)
86                 noise_mount_height = new Noise(&params->np_mount_height, seed, csize.X, csize.Z);
87
88         if (spflags & MGV7_FLOATLANDS) {
89                 noise_floatland_base    = new Noise(&params->np_floatland_base,    seed, csize.X, csize.Z);
90                 noise_float_base_height = new Noise(&params->np_float_base_height, seed, csize.X, csize.Z);
91         }
92
93         if (spflags & MGV7_RIDGES) {
94                 noise_ridge_uwater = new Noise(&params->np_ridge_uwater, seed, csize.X, csize.Z);
95         // 3D noise, 1-up 1-down overgeneration
96                 noise_ridge = new Noise(&params->np_ridge, seed, csize.X, csize.Y + 2, csize.Z);
97         }
98         // 3D noise, 1 up, 1 down overgeneration
99         if ((spflags & MGV7_MOUNTAINS) || (spflags & MGV7_FLOATLANDS))
100                 noise_mountain = new Noise(&params->np_mountain, seed, csize.X, csize.Y + 2, csize.Z);
101         // 3D noise, 1 down overgeneration
102         MapgenBasic::np_cave1  = params->np_cave1;
103         MapgenBasic::np_cave2  = params->np_cave2;
104         MapgenBasic::np_cavern = params->np_cavern;
105 }
106
107
108 MapgenV7::~MapgenV7()
109 {
110         delete noise_terrain_base;
111         delete noise_terrain_alt;
112         delete noise_terrain_persist;
113         delete noise_height_select;
114         delete noise_filler_depth;
115
116         if (spflags & MGV7_MOUNTAINS)
117                 delete noise_mount_height;
118
119         if (spflags & MGV7_FLOATLANDS) {
120                 delete noise_floatland_base;
121                 delete noise_float_base_height;
122         }
123
124         if (spflags & MGV7_RIDGES) {
125                 delete noise_ridge_uwater;
126                 delete noise_ridge;
127         }
128
129         if ((spflags & MGV7_MOUNTAINS) || (spflags & MGV7_FLOATLANDS))
130                 delete noise_mountain;
131 }
132
133
134 MapgenV7Params::MapgenV7Params():
135         np_terrain_base      (4,    70,   v3f(600,  600,  600),  82341, 5, 0.6,  2.0),
136         np_terrain_alt       (4,    25,   v3f(600,  600,  600),  5934,  5, 0.6,  2.0),
137         np_terrain_persist   (0.6,  0.1,  v3f(2000, 2000, 2000), 539,   3, 0.6,  2.0),
138         np_height_select     (-8,   16,   v3f(500,  500,  500),  4213,  6, 0.7,  2.0),
139         np_filler_depth      (0,    1.2,  v3f(150,  150,  150),  261,   3, 0.7,  2.0),
140         np_mount_height      (256,  112,  v3f(1000, 1000, 1000), 72449, 3, 0.6,  2.0),
141         np_ridge_uwater      (0,    1,    v3f(1000, 1000, 1000), 85039, 5, 0.6,  2.0),
142         np_floatland_base    (-0.6, 1.5,  v3f(600,  600,  600),  114,   5, 0.6,  2.0),
143         np_float_base_height (48,   24,   v3f(300,  300,  300),  907,   4, 0.7,  2.0),
144         np_mountain          (-0.6, 1,    v3f(250,  350,  250),  5333,  5, 0.63, 2.0),
145         np_ridge             (0,    1,    v3f(100,  100,  100),  6467,  4, 0.75, 2.0),
146         np_cavern            (0,    1,    v3f(384,  128,  384),  723,   5, 0.63, 2.0),
147         np_cave1             (0,    12,   v3f(61,   61,   61),   52534, 3, 0.5,  2.0),
148         np_cave2             (0,    12,   v3f(67,   67,   67),   10325, 3, 0.5,  2.0)
149 {
150 }
151
152
153 void MapgenV7Params::readParams(const Settings *settings)
154 {
155         settings->getFlagStrNoEx("mgv7_spflags",            spflags, flagdesc_mapgen_v7);
156         settings->getS16NoEx("mgv7_mount_zero_level",       mount_zero_level);
157         settings->getFloatNoEx("mgv7_cave_width",           cave_width);
158         settings->getS16NoEx("mgv7_large_cave_depth",       large_cave_depth);
159         settings->getS16NoEx("mgv7_lava_depth",             lava_depth);
160         settings->getFloatNoEx("mgv7_float_mount_density",  float_mount_density);
161         settings->getFloatNoEx("mgv7_float_mount_height",   float_mount_height);
162         settings->getFloatNoEx("mgv7_float_mount_exponent", float_mount_exponent);
163         settings->getS16NoEx("mgv7_floatland_level",        floatland_level);
164         settings->getS16NoEx("mgv7_shadow_limit",           shadow_limit);
165         settings->getS16NoEx("mgv7_cavern_limit",           cavern_limit);
166         settings->getS16NoEx("mgv7_cavern_taper",           cavern_taper);
167         settings->getFloatNoEx("mgv7_cavern_threshold",     cavern_threshold);
168         settings->getS16NoEx("mgv7_dungeon_ymin",           dungeon_ymin);
169         settings->getS16NoEx("mgv7_dungeon_ymax",           dungeon_ymax);
170
171         settings->getNoiseParams("mgv7_np_terrain_base",      np_terrain_base);
172         settings->getNoiseParams("mgv7_np_terrain_alt",       np_terrain_alt);
173         settings->getNoiseParams("mgv7_np_terrain_persist",   np_terrain_persist);
174         settings->getNoiseParams("mgv7_np_height_select",     np_height_select);
175         settings->getNoiseParams("mgv7_np_filler_depth",      np_filler_depth);
176         settings->getNoiseParams("mgv7_np_mount_height",      np_mount_height);
177         settings->getNoiseParams("mgv7_np_ridge_uwater",      np_ridge_uwater);
178         settings->getNoiseParams("mgv7_np_floatland_base",    np_floatland_base);
179         settings->getNoiseParams("mgv7_np_float_base_height", np_float_base_height);
180         settings->getNoiseParams("mgv7_np_mountain",          np_mountain);
181         settings->getNoiseParams("mgv7_np_ridge",             np_ridge);
182         settings->getNoiseParams("mgv7_np_cavern",            np_cavern);
183         settings->getNoiseParams("mgv7_np_cave1",             np_cave1);
184         settings->getNoiseParams("mgv7_np_cave2",             np_cave2);
185 }
186
187
188 void MapgenV7Params::writeParams(Settings *settings) const
189 {
190         settings->setFlagStr("mgv7_spflags",            spflags, flagdesc_mapgen_v7, U32_MAX);
191         settings->setS16("mgv7_mount_zero_level",       mount_zero_level);
192         settings->setFloat("mgv7_cave_width",           cave_width);
193         settings->setS16("mgv7_large_cave_depth",       large_cave_depth);
194         settings->setS16("mgv7_lava_depth",             lava_depth);
195         settings->setFloat("mgv7_float_mount_density",  float_mount_density);
196         settings->setFloat("mgv7_float_mount_height",   float_mount_height);
197         settings->setFloat("mgv7_float_mount_exponent", float_mount_exponent);
198         settings->setS16("mgv7_floatland_level",        floatland_level);
199         settings->setS16("mgv7_shadow_limit",           shadow_limit);
200         settings->setS16("mgv7_cavern_limit",           cavern_limit);
201         settings->setS16("mgv7_cavern_taper",           cavern_taper);
202         settings->setFloat("mgv7_cavern_threshold",     cavern_threshold);
203         settings->setS16("mgv7_dungeon_ymin",           dungeon_ymin);
204         settings->setS16("mgv7_dungeon_ymax",           dungeon_ymax);
205
206         settings->setNoiseParams("mgv7_np_terrain_base",      np_terrain_base);
207         settings->setNoiseParams("mgv7_np_terrain_alt",       np_terrain_alt);
208         settings->setNoiseParams("mgv7_np_terrain_persist",   np_terrain_persist);
209         settings->setNoiseParams("mgv7_np_height_select",     np_height_select);
210         settings->setNoiseParams("mgv7_np_filler_depth",      np_filler_depth);
211         settings->setNoiseParams("mgv7_np_mount_height",      np_mount_height);
212         settings->setNoiseParams("mgv7_np_ridge_uwater",      np_ridge_uwater);
213         settings->setNoiseParams("mgv7_np_floatland_base",    np_floatland_base);
214         settings->setNoiseParams("mgv7_np_float_base_height", np_float_base_height);
215         settings->setNoiseParams("mgv7_np_mountain",          np_mountain);
216         settings->setNoiseParams("mgv7_np_ridge",             np_ridge);
217         settings->setNoiseParams("mgv7_np_cavern",            np_cavern);
218         settings->setNoiseParams("mgv7_np_cave1",             np_cave1);
219         settings->setNoiseParams("mgv7_np_cave2",             np_cave2);
220 }
221
222
223 ///////////////////////////////////////////////////////////////////////////////
224
225
226 int MapgenV7::getSpawnLevelAtPoint(v2s16 p)
227 {
228         // If rivers are enabled, first check if in a river
229         if (spflags & MGV7_RIDGES) {
230                 float width = 0.2;
231                 float uwatern = NoisePerlin2D(&noise_ridge_uwater->np, p.X, p.Y, seed) * 2;
232                 if (std::fabs(uwatern) <= width)
233                         return MAX_MAP_GENERATION_LIMIT;  // Unsuitable spawn point
234         }
235
236         // Terrain noise 'offset' is the average level of that terrain.
237         // At least 50% of terrain will be below the higher of base and alt terrain
238         // 'offset's.
239         // Raising the maximum spawn level above 'water_level + 16' is necessary
240         // for when terrain 'offset's are set much higher than water_level.
241         s16 max_spawn_y = MYMAX(MYMAX(noise_terrain_alt->np.offset,
242                         noise_terrain_base->np.offset),
243                         water_level + 16);
244         // Base terrain calculation
245         s16 y = baseTerrainLevelAtPoint(p.X, p.Y);
246
247         // If mountains are disabled, terrain level is base terrain level.
248         // Avoids mid-air spawn where mountain terrain would have been.
249         if (!(spflags & MGV7_MOUNTAINS)) {
250                 if (y < water_level || y > max_spawn_y)
251                         return MAX_MAP_GENERATION_LIMIT;  // Unsuitable spawn point
252
253                 // y + 2 because y is surface level and due to biome 'dust'
254                 return y + 2;
255         }
256
257         // Search upwards for first node without mountain terrain
258         int iters = 256;
259         while (iters > 0 && y <= max_spawn_y) {
260                 if (!getMountainTerrainAtPoint(p.X, y + 1, p.Y)) {
261                         if (y <= water_level || y > max_spawn_y)
262                                 return MAX_MAP_GENERATION_LIMIT;  // Unsuitable spawn point
263
264                         // y + 1 due to biome 'dust'
265                         return y + 1;
266                 }
267                 y++;
268                 iters--;
269         }
270
271         // Unsuitable spawn point
272         return MAX_MAP_GENERATION_LIMIT;
273 }
274
275
276 void MapgenV7::makeChunk(BlockMakeData *data)
277 {
278         // Pre-conditions
279         assert(data->vmanip);
280         assert(data->nodedef);
281         assert(data->blockpos_requested.X >= data->blockpos_min.X &&
282                 data->blockpos_requested.Y >= data->blockpos_min.Y &&
283                 data->blockpos_requested.Z >= data->blockpos_min.Z);
284         assert(data->blockpos_requested.X <= data->blockpos_max.X &&
285                 data->blockpos_requested.Y <= data->blockpos_max.Y &&
286                 data->blockpos_requested.Z <= data->blockpos_max.Z);
287
288         this->generating = true;
289         this->vm   = data->vmanip;
290         this->ndef = data->nodedef;
291         //TimeTaker t("makeChunk");
292
293         v3s16 blockpos_min = data->blockpos_min;
294         v3s16 blockpos_max = data->blockpos_max;
295         node_min = blockpos_min * MAP_BLOCKSIZE;
296         node_max = (blockpos_max + v3s16(1, 1, 1)) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
297         full_node_min = (blockpos_min - 1) * MAP_BLOCKSIZE;
298         full_node_max = (blockpos_max + 2) * MAP_BLOCKSIZE - v3s16(1, 1, 1);
299
300         blockseed = getBlockSeed2(full_node_min, seed);
301
302         // Generate base and mountain terrain
303         // An initial heightmap is no longer created here for use in generateRidgeTerrain()
304         s16 stone_surface_max_y = generateTerrain();
305
306         // Generate rivers
307         if (spflags & MGV7_RIDGES)
308                 generateRidgeTerrain();
309
310         // Create heightmap
311         updateHeightmap(node_min, node_max);
312
313         // Init biome generator, place biome-specific nodes, and build biomemap
314         biomegen->calcBiomeNoise(node_min);
315
316         MgStoneType mgstone_type;
317         content_t biome_stone;
318         generateBiomes(&mgstone_type, &biome_stone);
319
320         // Generate caverns, tunnels and classic caves
321         if (flags & MG_CAVES) {
322                 bool near_cavern = false;
323                 // Generate caverns
324                 if (spflags & MGV7_CAVERNS)
325                         near_cavern = generateCaverns(stone_surface_max_y);
326                 // Generate tunnels and classic caves
327                 if (near_cavern)
328                         // Disable classic caves in this mapchunk by setting
329                         // 'large cave depth' to world base. Avoids excessive liquid in
330                         // large caverns and floating blobs of overgenerated liquid.
331                         generateCaves(stone_surface_max_y, -MAX_MAP_GENERATION_LIMIT);
332                 else
333                         generateCaves(stone_surface_max_y, large_cave_depth);
334         }
335
336         // Generate dungeons
337         if ((flags & MG_DUNGEONS) && full_node_min.Y >= dungeon_ymin &&
338                         full_node_max.Y <= dungeon_ymax)
339                 generateDungeons(stone_surface_max_y, mgstone_type, biome_stone);
340
341         // Generate the registered decorations
342         if (flags & MG_DECORATIONS)
343                 m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max);
344
345         // Generate the registered ores
346         m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max);
347
348         // Sprinkle some dust on top after everything else was generated
349         dustTopNodes();
350
351         //printf("makeChunk: %dms\n", t.stop());
352
353         // Update liquids
354         updateLiquid(&data->transforming_liquid, full_node_min, full_node_max);
355
356         // Calculate lighting
357         // Limit floatland shadow
358         bool propagate_shadow = !((spflags & MGV7_FLOATLANDS) &&
359                 node_min.Y <= shadow_limit && node_max.Y >= shadow_limit);
360
361         if (flags & MG_LIGHT)
362                 calcLighting(node_min - v3s16(0, 1, 0), node_max + v3s16(0, 1, 0),
363                         full_node_min, full_node_max, propagate_shadow);
364
365         //setLighting(node_min - v3s16(1, 0, 1) * MAP_BLOCKSIZE,
366         //                      node_max + v3s16(1, 0, 1) * MAP_BLOCKSIZE, 0xFF);
367
368         this->generating = false;
369 }
370
371
372 float MapgenV7::baseTerrainLevelAtPoint(s16 x, s16 z)
373 {
374         float hselect = NoisePerlin2D(&noise_height_select->np, x, z, seed);
375         hselect = rangelim(hselect, 0.0, 1.0);
376
377         float persist = NoisePerlin2D(&noise_terrain_persist->np, x, z, seed);
378
379         noise_terrain_base->np.persist = persist;
380         float height_base = NoisePerlin2D(&noise_terrain_base->np, x, z, seed);
381
382         noise_terrain_alt->np.persist = persist;
383         float height_alt = NoisePerlin2D(&noise_terrain_alt->np, x, z, seed);
384
385         if (height_alt > height_base)
386                 return height_alt;
387
388         return (height_base * hselect) + (height_alt * (1.0 - hselect));
389 }
390
391
392 float MapgenV7::baseTerrainLevelFromMap(int index)
393 {
394         float hselect     = rangelim(noise_height_select->result[index], 0.0, 1.0);
395         float height_base = noise_terrain_base->result[index];
396         float height_alt  = noise_terrain_alt->result[index];
397
398         if (height_alt > height_base)
399                 return height_alt;
400
401         return (height_base * hselect) + (height_alt * (1.0 - hselect));
402 }
403
404
405 bool MapgenV7::getMountainTerrainAtPoint(s16 x, s16 y, s16 z)
406 {
407         float mnt_h_n =
408                         MYMAX(NoisePerlin2D(&noise_mount_height->np, x, z, seed), 1.0f);
409         float density_gradient = -((float)(y - mount_zero_level) / mnt_h_n);
410         float mnt_n = NoisePerlin3D(&noise_mountain->np, x, y, z, seed);
411
412         return mnt_n + density_gradient >= 0.0;
413 }
414
415
416 bool MapgenV7::getMountainTerrainFromMap(int idx_xyz, int idx_xz, s16 y)
417 {
418         float mounthn = MYMAX(noise_mount_height->result[idx_xz], 1.0f);
419         float density_gradient = -((float)(y - mount_zero_level) / mounthn);
420         float mountn = noise_mountain->result[idx_xyz];
421
422         return mountn + density_gradient >= 0.0;
423 }
424
425
426 bool MapgenV7::getFloatlandMountainFromMap(int idx_xyz, int idx_xz, s16 y)
427 {
428         // Make rim 2 nodes thick to match floatland base terrain
429         float density_gradient = (y >= floatland_level) ?
430                 -std::pow((float)(y - floatland_level) / float_mount_height,
431                 float_mount_exponent) :
432                 -std::pow((float)(floatland_level - 1 - y) / float_mount_height,
433                 float_mount_exponent);
434
435         float floatn = noise_mountain->result[idx_xyz] + float_mount_density;
436
437         return floatn + density_gradient >= 0.0f;
438 }
439
440
441 void MapgenV7::floatBaseExtentFromMap(s16 *float_base_min, s16 *float_base_max, int idx_xz)
442 {
443         // '+1' to avoid a layer of stone at y = MAX_MAP_GENERATION_LIMIT
444         s16 base_min = MAX_MAP_GENERATION_LIMIT + 1;
445         s16 base_max = MAX_MAP_GENERATION_LIMIT;
446
447         float n_base = noise_floatland_base->result[idx_xz];
448         if (n_base > 0.0f) {
449                 float n_base_height =
450                                 MYMAX(noise_float_base_height->result[idx_xz], 1.0f);
451                 float amp = n_base * n_base_height;
452                 float ridge = n_base_height / 3.0f;
453                 base_min = floatland_level - amp / 1.5f;
454
455                 if (amp > ridge * 2.0f) {
456                         // Lake bed
457                         base_max = floatland_level - (amp - ridge * 2.0f) / 2.0f;
458                 } else {
459                         // Hills and ridges
460                         float diff = std::fabs(amp - ridge) / ridge;
461                         // Smooth ridges using the 'smoothstep function'
462                         float smooth_diff = diff * diff * (3.0f - 2.0f * diff);
463                         base_max = floatland_level + ridge - smooth_diff * ridge;
464                 }
465         }
466
467         *float_base_min = base_min;
468         *float_base_max = base_max;
469 }
470
471
472 int MapgenV7::generateTerrain()
473 {
474         MapNode n_air(CONTENT_AIR);
475         MapNode n_stone(c_stone);
476         MapNode n_water(c_water_source);
477
478         //// Calculate noise for terrain generation
479         noise_terrain_persist->perlinMap2D(node_min.X, node_min.Z);
480         float *persistmap = noise_terrain_persist->result;
481
482         noise_terrain_base->perlinMap2D(node_min.X, node_min.Z, persistmap);
483         noise_terrain_alt->perlinMap2D(node_min.X, node_min.Z, persistmap);
484         noise_height_select->perlinMap2D(node_min.X, node_min.Z);
485
486         if ((spflags & MGV7_MOUNTAINS) || (spflags & MGV7_FLOATLANDS)) {
487                 noise_mountain->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
488         }
489
490         if (spflags & MGV7_MOUNTAINS) {
491                 noise_mount_height->perlinMap2D(node_min.X, node_min.Z);
492         }
493
494         if (spflags & MGV7_FLOATLANDS) {
495                 noise_floatland_base->perlinMap2D(node_min.X, node_min.Z);
496                 noise_float_base_height->perlinMap2D(node_min.X, node_min.Z);
497         }
498
499         //// Place nodes
500         const v3s16 &em = vm->m_area.getExtent();
501         s16 stone_surface_max_y = -MAX_MAP_GENERATION_LIMIT;
502         u32 index2d = 0;
503
504         for (s16 z = node_min.Z; z <= node_max.Z; z++)
505         for (s16 x = node_min.X; x <= node_max.X; x++, index2d++) {
506                 s16 surface_y = baseTerrainLevelFromMap(index2d);
507                 if (surface_y > stone_surface_max_y)
508                         stone_surface_max_y = surface_y;
509
510                 // Get extent of floatland base terrain
511                 // '+1' to avoid a layer of stone at y = MAX_MAP_GENERATION_LIMIT
512                 s16 float_base_min = MAX_MAP_GENERATION_LIMIT + 1;
513                 s16 float_base_max = MAX_MAP_GENERATION_LIMIT;
514                 if (spflags & MGV7_FLOATLANDS)
515                         floatBaseExtentFromMap(&float_base_min, &float_base_max, index2d);
516
517                 u32 vi = vm->m_area.index(x, node_min.Y - 1, z);
518                 u32 index3d = (z - node_min.Z) * zstride_1u1d + (x - node_min.X);
519
520                 for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
521                         if (vm->m_data[vi].getContent() == CONTENT_IGNORE) {
522                                 if (y <= surface_y) {
523                                         vm->m_data[vi] = n_stone;  // Base terrain
524                                 } else if ((spflags & MGV7_MOUNTAINS) &&
525                                                 getMountainTerrainFromMap(index3d, index2d, y)) {
526                                         vm->m_data[vi] = n_stone;  // Mountain terrain
527                                         if (y > stone_surface_max_y)
528                                                 stone_surface_max_y = y;
529                                 } else if ((spflags & MGV7_FLOATLANDS) &&
530                                                 ((y >= float_base_min && y <= float_base_max) ||
531                                                 getFloatlandMountainFromMap(index3d, index2d, y))) {
532                                         vm->m_data[vi] = n_stone;  // Floatland terrain
533                                         stone_surface_max_y = node_max.Y;
534                                 } else if (y <= water_level) {
535                                         vm->m_data[vi] = n_water;  // Ground level water
536                                 } else if ((spflags & MGV7_FLOATLANDS) &&
537                                                 (y >= float_base_max && y <= floatland_level)) {
538                                         vm->m_data[vi] = n_water;  // Floatland water
539                                 } else {
540                                         vm->m_data[vi] = n_air;
541                                 }
542                         }
543                         VoxelArea::add_y(em, vi, 1);
544                         index3d += ystride;
545                 }
546         }
547
548         return stone_surface_max_y;
549 }
550
551
552 void MapgenV7::generateRidgeTerrain()
553 {
554         if (node_max.Y < water_level - 16 ||
555                         ((spflags & MGV7_FLOATLANDS) && node_max.Y > shadow_limit))
556                 return;
557
558         noise_ridge->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z);
559         noise_ridge_uwater->perlinMap2D(node_min.X, node_min.Z);
560
561         MapNode n_water(c_water_source);
562         MapNode n_air(CONTENT_AIR);
563         u32 index = 0;
564         float width = 0.2;
565
566         for (s16 z = node_min.Z; z <= node_max.Z; z++)
567         for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
568                 u32 vi = vm->m_area.index(node_min.X, y, z);
569                 for (s16 x = node_min.X; x <= node_max.X; x++, index++, vi++) {
570                         int j = (z - node_min.Z) * csize.X + (x - node_min.X);
571
572                         float uwatern = noise_ridge_uwater->result[j] * 2;
573                         if (std::fabs(uwatern) > width)
574                                 continue;
575
576                         float altitude = y - water_level;
577                         float height_mod = (altitude + 17) / 2.5;
578                         float width_mod  = width - fabs(uwatern);
579                         float nridge = noise_ridge->result[index] * MYMAX(altitude, 0) / 7.0;
580
581                         if (nridge + width_mod * height_mod < 0.6)
582                                 continue;
583
584                         vm->m_data[vi] = (y > water_level) ? n_air : n_water;
585                 }
586         }
587 }