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Diffstat (limited to 'src/mapgen/mapgen_valleys.cpp')
| -rw-r--r-- | src/mapgen/mapgen_valleys.cpp | 743 |
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diff --git a/src/mapgen/mapgen_valleys.cpp b/src/mapgen/mapgen_valleys.cpp new file mode 100644 index 000000000..a13bb4582 --- /dev/null +++ b/src/mapgen/mapgen_valleys.cpp @@ -0,0 +1,743 @@ +/* +Minetest Valleys C +Copyright (C) 2016-2017 Duane Robertson <duane@duanerobertson.com> +Copyright (C) 2016-2017 paramat + +Based on Valleys Mapgen by Gael de Sailly + (https://forum.minetest.net/viewtopic.php?f=9&t=11430) +and mapgen_v7, mapgen_flat by kwolekr and paramat. + +Licensing changed by permission of Gael de Sailly. + +This program is free software; you can redistribute it and/or modify +it under the terms of the GNU Lesser General Public License as published by +the Free Software Foundation; either version 2.1 of the License, or +(at your option) any later version. + +This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU Lesser General Public License for more details. + +You should have received a copy of the GNU Lesser General Public License along +with this program; if not, write to the Free Software Foundation, Inc., +51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. +*/ + +#include "mapgen.h" +#include "voxel.h" +#include "noise.h" +#include "mapblock.h" +#include "mapnode.h" +#include "map.h" +#include "nodedef.h" +#include "voxelalgorithms.h" +#include "settings.h" // For g_settings +#include "emerge.h" +#include "dungeongen.h" +#include "mg_biome.h" +#include "mg_ore.h" +#include "mg_decoration.h" +#include "mapgen_valleys.h" +#include "cavegen.h" + + +//#undef NDEBUG +//#include "assert.h" + +//#include "util/timetaker.h" +//#include "profiler.h" + + +//static Profiler mapgen_prof; +//Profiler *mapgen_profiler = &mapgen_prof; + +static FlagDesc flagdesc_mapgen_valleys[] = { + {"altitude_chill", MGVALLEYS_ALT_CHILL}, + {"humid_rivers", MGVALLEYS_HUMID_RIVERS}, + {NULL, 0} +}; + +/////////////////////////////////////////////////////////////////////////////// + + +MapgenValleys::MapgenValleys(int mapgenid, MapgenValleysParams *params, EmergeManager *emerge) + : MapgenBasic(mapgenid, params, emerge) +{ + // NOTE: MapgenValleys has a hard dependency on BiomeGenOriginal + m_bgen = (BiomeGenOriginal *)biomegen; + + BiomeParamsOriginal *bp = (BiomeParamsOriginal *)params->bparams; + + spflags = params->spflags; + altitude_chill = params->altitude_chill; + large_cave_depth = params->large_cave_depth; + lava_features_lim = rangelim(params->lava_features, 0, 10); + massive_cave_depth = params->massive_cave_depth; + river_depth_bed = params->river_depth + 1.f; + river_size_factor = params->river_size / 100.f; + water_features_lim = rangelim(params->water_features, 0, 10); + cave_width = params->cave_width; + + //// 2D Terrain noise + noise_filler_depth = new Noise(¶ms->np_filler_depth, seed, csize.X, csize.Z); + noise_inter_valley_slope = new Noise(¶ms->np_inter_valley_slope, seed, csize.X, csize.Z); + noise_rivers = new Noise(¶ms->np_rivers, seed, csize.X, csize.Z); + noise_terrain_height = new Noise(¶ms->np_terrain_height, seed, csize.X, csize.Z); + noise_valley_depth = new Noise(¶ms->np_valley_depth, seed, csize.X, csize.Z); + noise_valley_profile = new Noise(¶ms->np_valley_profile, seed, csize.X, csize.Z); + + //// 3D Terrain noise + // 1-up 1-down overgeneration + noise_inter_valley_fill = new Noise(¶ms->np_inter_valley_fill, seed, csize.X, csize.Y + 2, csize.Z); + // 1-down overgeneraion + noise_cave1 = new Noise(¶ms->np_cave1, seed, csize.X, csize.Y + 1, csize.Z); + noise_cave2 = new Noise(¶ms->np_cave2, seed, csize.X, csize.Y + 1, csize.Z); + noise_massive_caves = new Noise(¶ms->np_massive_caves, seed, csize.X, csize.Y + 1, csize.Z); + + humid_rivers = (spflags & MGVALLEYS_HUMID_RIVERS); + use_altitude_chill = (spflags & MGVALLEYS_ALT_CHILL); + humidity_adjust = bp->np_humidity.offset - 50.f; + + // a small chance of overflows if the settings are very high + cave_water_max_height = water_level + MYMAX(0, water_features_lim - 4) * 50; + lava_max_height = water_level + MYMAX(0, lava_features_lim - 4) * 50; + + tcave_cache = new float[csize.Y + 2]; +} + + +MapgenValleys::~MapgenValleys() +{ + delete noise_cave1; + delete noise_cave2; + delete noise_filler_depth; + delete noise_inter_valley_fill; + delete noise_inter_valley_slope; + delete noise_rivers; + delete noise_massive_caves; + delete noise_terrain_height; + delete noise_valley_depth; + delete noise_valley_profile; + + delete[] tcave_cache; +} + + +MapgenValleysParams::MapgenValleysParams(): + np_cave1 (0, 12, v3f(61, 61, 61), 52534, 3, 0.5, 2.0), + np_cave2 (0, 12, v3f(67, 67, 67), 10325, 3, 0.5, 2.0), + np_filler_depth (0.f, 1.2f, v3f(256, 256, 256), 1605, 3, 0.5f, 2.f), + np_inter_valley_fill (0.f, 1.f, v3f(256, 512, 256), 1993, 6, 0.8f, 2.f), + np_inter_valley_slope (0.5f, 0.5f, v3f(128, 128, 128), 746, 1, 1.f, 2.f), + np_rivers (0.f, 1.f, v3f(256, 256, 256), -6050, 5, 0.6f, 2.f), + np_massive_caves (0.f, 1.f, v3f(768, 256, 768), 59033, 6, 0.63f, 2.f), + np_terrain_height (-10.f, 50.f, v3f(1024, 1024, 1024), 5202, 6, 0.4f, 2.f), + np_valley_depth (5.f, 4.f, v3f(512, 512, 512), -1914, 1, 1.f, 2.f), + np_valley_profile (0.6f, 0.5f, v3f(512, 512, 512), 777, 1, 1.f, 2.f) +{ +} + + +void MapgenValleysParams::readParams(const Settings *settings) +{ + settings->getFlagStrNoEx("mgvalleys_spflags", spflags, flagdesc_mapgen_valleys); + settings->getU16NoEx("mgvalleys_altitude_chill", altitude_chill); + settings->getS16NoEx("mgvalleys_large_cave_depth", large_cave_depth); + settings->getU16NoEx("mgvalleys_lava_features", lava_features); + settings->getS16NoEx("mgvalleys_massive_cave_depth", massive_cave_depth); + settings->getU16NoEx("mgvalleys_river_depth", river_depth); + settings->getU16NoEx("mgvalleys_river_size", river_size); + settings->getU16NoEx("mgvalleys_water_features", water_features); + settings->getFloatNoEx("mgvalleys_cave_width", cave_width); + + settings->getNoiseParams("mgvalleys_np_cave1", np_cave1); + settings->getNoiseParams("mgvalleys_np_cave2", np_cave2); + settings->getNoiseParams("mgvalleys_np_filler_depth", np_filler_depth); + settings->getNoiseParams("mgvalleys_np_inter_valley_fill", np_inter_valley_fill); + settings->getNoiseParams("mgvalleys_np_inter_valley_slope", np_inter_valley_slope); + settings->getNoiseParams("mgvalleys_np_rivers", np_rivers); + settings->getNoiseParams("mgvalleys_np_massive_caves", np_massive_caves); + settings->getNoiseParams("mgvalleys_np_terrain_height", np_terrain_height); + settings->getNoiseParams("mgvalleys_np_valley_depth", np_valley_depth); + settings->getNoiseParams("mgvalleys_np_valley_profile", np_valley_profile); +} + + +void MapgenValleysParams::writeParams(Settings *settings) const +{ + settings->setFlagStr("mgvalleys_spflags", spflags, flagdesc_mapgen_valleys, U32_MAX); + settings->setU16("mgvalleys_altitude_chill", altitude_chill); + settings->setS16("mgvalleys_large_cave_depth", large_cave_depth); + settings->setU16("mgvalleys_lava_features", lava_features); + settings->setS16("mgvalleys_massive_cave_depth", massive_cave_depth); + settings->setU16("mgvalleys_river_depth", river_depth); + settings->setU16("mgvalleys_river_size", river_size); + settings->setU16("mgvalleys_water_features", water_features); + settings->setFloat("mgvalleys_cave_width", cave_width); + + settings->setNoiseParams("mgvalleys_np_cave1", np_cave1); + settings->setNoiseParams("mgvalleys_np_cave2", np_cave2); + settings->setNoiseParams("mgvalleys_np_filler_depth", np_filler_depth); + settings->setNoiseParams("mgvalleys_np_inter_valley_fill", np_inter_valley_fill); + settings->setNoiseParams("mgvalleys_np_inter_valley_slope", np_inter_valley_slope); + settings->setNoiseParams("mgvalleys_np_rivers", np_rivers); + settings->setNoiseParams("mgvalleys_np_massive_caves", np_massive_caves); + settings->setNoiseParams("mgvalleys_np_terrain_height", np_terrain_height); + settings->setNoiseParams("mgvalleys_np_valley_depth", np_valley_depth); + settings->setNoiseParams("mgvalleys_np_valley_profile", np_valley_profile); +} + + +/////////////////////////////////////// + + +void MapgenValleys::makeChunk(BlockMakeData *data) +{ + // Pre-conditions + assert(data->vmanip); + assert(data->nodedef); + assert(data->blockpos_requested.X >= data->blockpos_min.X && + data->blockpos_requested.Y >= data->blockpos_min.Y && + data->blockpos_requested.Z >= data->blockpos_min.Z); + assert(data->blockpos_requested.X <= data->blockpos_max.X && + data->blockpos_requested.Y <= data->blockpos_max.Y && + data->blockpos_requested.Z <= data->blockpos_max.Z); + + this->generating = true; + this->vm = data->vmanip; + this->ndef = data->nodedef; + + //TimeTaker t("makeChunk"); + + v3s16 blockpos_min = data->blockpos_min; + v3s16 blockpos_max = data->blockpos_max; + node_min = blockpos_min * MAP_BLOCKSIZE; + node_max = (blockpos_max + v3s16(1, 1, 1)) * MAP_BLOCKSIZE - v3s16(1, 1, 1); + full_node_min = (blockpos_min - 1) * MAP_BLOCKSIZE; + full_node_max = (blockpos_max + 2) * MAP_BLOCKSIZE - v3s16(1, 1, 1); + + blockseed = getBlockSeed2(full_node_min, seed); + + // Generate biome noises. Note this must be executed strictly before + // generateTerrain, because generateTerrain depends on intermediate + // biome-related noises. + m_bgen->calcBiomeNoise(node_min); + + // Generate noise maps and base terrain height. + // Modify heat and humidity maps. + calculateNoise(); + + // Generate base terrain with initial heightmaps + s16 stone_surface_max_y = generateTerrain(); + + // Recalculate heightmap + updateHeightmap(node_min, node_max); + + // Place biome-specific nodes and build biomemap + MgStoneType mgstone_type; + content_t biome_stone; + generateBiomes(&mgstone_type, &biome_stone); + + // Cave creation. + if (flags & MG_CAVES) + generateCaves(stone_surface_max_y, large_cave_depth); + + // Dungeon creation + if ((flags & MG_DUNGEONS) && node_max.Y < 50) + generateDungeons(stone_surface_max_y, mgstone_type, biome_stone); + + // Generate the registered decorations + if (flags & MG_DECORATIONS) + m_emerge->decomgr->placeAllDecos(this, blockseed, node_min, node_max); + + // Generate the registered ores + m_emerge->oremgr->placeAllOres(this, blockseed, node_min, node_max); + + // Sprinkle some dust on top after everything else was generated + dustTopNodes(); + + //TimeTaker tll("liquid_lighting"); + + updateLiquid(&data->transforming_liquid, full_node_min, full_node_max); + + if (flags & MG_LIGHT) + calcLighting( + node_min - v3s16(0, 1, 0), + node_max + v3s16(0, 1, 0), + full_node_min, + full_node_max); + + //mapgen_profiler->avg("liquid_lighting", tll.stop() / 1000.f); + //mapgen_profiler->avg("makeChunk", t.stop() / 1000.f); + + this->generating = false; +} + + +// Populate the noise tables and do most of the +// calculation necessary to determine terrain height. +void MapgenValleys::calculateNoise() +{ + //TimeTaker t("calculateNoise", NULL, PRECISION_MICRO); + + int x = node_min.X; + int y = node_min.Y - 1; + int z = node_min.Z; + + //TimeTaker tcn("actualNoise"); + + noise_inter_valley_slope->perlinMap2D(x, z); + noise_rivers->perlinMap2D(x, z); + noise_terrain_height->perlinMap2D(x, z); + noise_valley_depth->perlinMap2D(x, z); + noise_valley_profile->perlinMap2D(x, z); + + noise_inter_valley_fill->perlinMap3D(x, y, z); + + //mapgen_profiler->avg("noisemaps", tcn.stop() / 1000.f); + + float heat_offset = 0.f; + float humidity_scale = 1.f; + + // Altitude chill tends to reduce the average heat. + if (use_altitude_chill) + heat_offset = 5.f; + + // River humidity tends to increase the humidity range. + if (humid_rivers) { + humidity_scale = 0.8f; + } + + for (s32 index = 0; index < csize.X * csize.Z; index++) { + m_bgen->heatmap[index] += heat_offset; + m_bgen->humidmap[index] *= humidity_scale; + } + + TerrainNoise tn; + + u32 index = 0; + for (tn.z = node_min.Z; tn.z <= node_max.Z; tn.z++) + for (tn.x = node_min.X; tn.x <= node_max.X; tn.x++, index++) { + // The parameters that we actually need to generate terrain + // are passed by address (and the return value). + tn.terrain_height = noise_terrain_height->result[index]; + // River noise is replaced with base terrain, which + // is basically the height of the water table. + tn.rivers = &noise_rivers->result[index]; + // Valley depth noise is replaced with the valley + // number that represents the height of terrain + // over rivers and is used to determine about + // how close a river is for humidity calculation. + tn.valley = &noise_valley_depth->result[index]; + tn.valley_profile = noise_valley_profile->result[index]; + // Slope noise is replaced by the calculated slope + // which is used to get terrain height in the slow + // method, to create sharper mountains. + tn.slope = &noise_inter_valley_slope->result[index]; + tn.inter_valley_fill = noise_inter_valley_fill->result[index]; + + // This is the actual terrain height. + float mount = terrainLevelFromNoise(&tn); + noise_terrain_height->result[index] = mount; + } +} + + +// This keeps us from having to maintain two similar sets of +// complicated code to determine ground level. +float MapgenValleys::terrainLevelFromNoise(TerrainNoise *tn) +{ + // The square function changes the behaviour of this noise: + // very often small, and sometimes very high. + float valley_d = MYSQUARE(*tn->valley); + + // valley_d is here because terrain is generally higher where valleys + // are deep (mountains). base represents the height of the + // rivers, most of the surface is above. + float base = tn->terrain_height + valley_d; + + // "river" represents the distance from the river, in arbitrary units. + float river = fabs(*tn->rivers) - river_size_factor; + + // Use the curve of the function 1-exp(-(x/a)^2) to model valleys. + // Making "a" vary (0 < a <= 1) changes the shape of the valleys. + // Try it with a geometry software ! + // (here x = "river" and a = valley_profile). + // "valley" represents the height of the terrain, from the rivers. + { + float t = river / tn->valley_profile; + *tn->valley = valley_d * (1.f - exp(- MYSQUARE(t))); + } + + // approximate height of the terrain at this point + float mount = base + *tn->valley; + + *tn->slope *= *tn->valley; + + // Rivers are placed where "river" is negative, so where the original + // noise value is close to zero. + // Base ground is returned as rivers since it's basically the water table. + *tn->rivers = base; + if (river < 0.f) { + // Use the the function -sqrt(1-x^2) which models a circle. + float depth; + { + float t = river / river_size_factor + 1; + depth = (river_depth_bed * sqrt(MYMAX(0, 1.f - MYSQUARE(t)))); + } + + // base - depth : height of the bottom of the river + // water_level - 3 : don't make rivers below 3 nodes under the surface + // We use three because that's as low as the swamp biomes go. + // There is no logical equivalent to this using rangelim. + mount = MYMIN(MYMAX(base - depth, (float)(water_level - 3)), mount); + + // Slope has no influence on rivers. + *tn->slope = 0.f; + } + + return mount; +} + + +// This avoids duplicating the code in terrainLevelFromNoise, adding +// only the final step of terrain generation without a noise map. +float MapgenValleys::adjustedTerrainLevelFromNoise(TerrainNoise *tn) +{ + float mount = terrainLevelFromNoise(tn); + s16 y_start = myround(mount); + + for (s16 y = y_start; y <= y_start + 1000; y++) { + float fill = NoisePerlin3D(&noise_inter_valley_fill->np, tn->x, y, tn->z, seed); + + if (fill * *tn->slope < y - mount) { + mount = MYMAX(y - 1, mount); + break; + } + } + + return mount; +} + + +int MapgenValleys::getSpawnLevelAtPoint(v2s16 p) +{ + // Check to make sure this isn't a request for a location in a river. + float rivers = NoisePerlin2D(&noise_rivers->np, p.X, p.Y, seed); + if (fabs(rivers) < river_size_factor) + return MAX_MAP_GENERATION_LIMIT; // Unsuitable spawn point + + s16 level_at_point = terrainLevelAtPoint(p.X, p.Y); + if (level_at_point <= water_level || + level_at_point > water_level + 32) + return MAX_MAP_GENERATION_LIMIT; // Unsuitable spawn point + + return level_at_point; +} + + +float MapgenValleys::terrainLevelAtPoint(s16 x, s16 z) +{ + TerrainNoise tn; + + float rivers = NoisePerlin2D(&noise_rivers->np, x, z, seed); + float valley = NoisePerlin2D(&noise_valley_depth->np, x, z, seed); + float inter_valley_slope = NoisePerlin2D(&noise_inter_valley_slope->np, x, z, seed); + + tn.x = x; + tn.z = z; + tn.terrain_height = NoisePerlin2D(&noise_terrain_height->np, x, z, seed); + tn.rivers = &rivers; + tn.valley = &valley; + tn.valley_profile = NoisePerlin2D(&noise_valley_profile->np, x, z, seed); + tn.slope = &inter_valley_slope; + tn.inter_valley_fill = 0.f; + + return adjustedTerrainLevelFromNoise(&tn); +} + + +int MapgenValleys::generateTerrain() +{ + // Raising this reduces the rate of evaporation. + static const float evaporation = 300.f; + // from the lua + static const float humidity_dropoff = 4.f; + // constant to convert altitude chill (compatible with lua) to heat + static const float alt_to_heat = 20.f; + // humidity reduction by altitude + static const float alt_to_humid = 10.f; + + MapNode n_air(CONTENT_AIR); + MapNode n_river_water(c_river_water_source); + MapNode n_stone(c_stone); + MapNode n_water(c_water_source); + + const v3s16 &em = vm->m_area.getExtent(); + s16 surface_max_y = -MAX_MAP_GENERATION_LIMIT; + u32 index_2d = 0; + + for (s16 z = node_min.Z; z <= node_max.Z; z++) + for (s16 x = node_min.X; x <= node_max.X; x++, index_2d++) { + float river_y = noise_rivers->result[index_2d]; + float surface_y = noise_terrain_height->result[index_2d]; + float slope = noise_inter_valley_slope->result[index_2d]; + float t_heat = m_bgen->heatmap[index_2d]; + + heightmap[index_2d] = -MAX_MAP_GENERATION_LIMIT; + + if (surface_y > surface_max_y) + surface_max_y = ceil(surface_y); + + if (humid_rivers) { + // Derive heat from (base) altitude. This will be most correct + // at rivers, since other surface heights may vary below. + if (use_altitude_chill && (surface_y > 0.f || river_y > 0.f)) + t_heat -= alt_to_heat * MYMAX(surface_y, river_y) / altitude_chill; + + // If humidity is low or heat is high, lower the water table. + float delta = m_bgen->humidmap[index_2d] - 50.f; + if (delta < 0.f) { + float t_evap = (t_heat - 32.f) / evaporation; + river_y += delta * MYMAX(t_evap, 0.08f); + } + } + + u32 index_3d = (z - node_min.Z) * zstride_1u1d + (x - node_min.X); + u32 index_data = vm->m_area.index(x, node_min.Y - 1, z); + + // Mapgens concern themselves with stone and water. + for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) { + if (vm->m_data[index_data].getContent() == CONTENT_IGNORE) { + float fill = noise_inter_valley_fill->result[index_3d]; + float surface_delta = (float)y - surface_y; + bool river = y + 1 < river_y; + + if (slope * fill > surface_delta) { + // ground + vm->m_data[index_data] = n_stone; + if (y > heightmap[index_2d]) + heightmap[index_2d] = y; + if (y > surface_max_y) + surface_max_y = y; + } else if (y <= water_level) { + // sea + vm->m_data[index_data] = n_water; + } else if (river) { + // river + vm->m_data[index_data] = n_river_water; + } else { // air + vm->m_data[index_data] = n_air; + } + } + + vm->m_area.add_y(em, index_data, 1); + index_3d += ystride; + } + + if (heightmap[index_2d] == -MAX_MAP_GENERATION_LIMIT) { + s16 surface_y_int = myround(surface_y); + if (surface_y_int > node_max.Y + 1 || surface_y_int < node_min.Y - 1) { + // If surface_y is outside the chunk, it's good enough. + heightmap[index_2d] = surface_y_int; + } else { + // If the ground is outside of this chunk, but surface_y + // is within the chunk, give a value outside. + heightmap[index_2d] = node_min.Y - 2; + } + } + + if (humid_rivers) { + // Use base ground (water table) in a riverbed, to + // avoid an unnatural rise in humidity. + float t_alt = MYMAX(noise_rivers->result[index_2d], (float)heightmap[index_2d]); + float humid = m_bgen->humidmap[index_2d]; + float water_depth = (t_alt - river_y) / humidity_dropoff; + humid *= 1.f + pow(0.5f, MYMAX(water_depth, 1.f)); + + // Reduce humidity with altitude (ignoring riverbeds). + // This is similar to the lua version's seawater adjustment, + // but doesn't increase the base humidity, which causes + // problems with the default biomes. + if (t_alt > 0.f) + humid -= alt_to_humid * t_alt / altitude_chill; + + m_bgen->humidmap[index_2d] = humid; + } + + // Assign the heat adjusted by any changed altitudes. + // The altitude will change about half the time. + if (use_altitude_chill) { + // ground height ignoring riverbeds + float t_alt = MYMAX(noise_rivers->result[index_2d], (float)heightmap[index_2d]); + if (humid_rivers && heightmap[index_2d] == (s16)myround(surface_y)) + // The altitude hasn't changed. Use the first result. + m_bgen->heatmap[index_2d] = t_heat; + else if (t_alt > 0.f) + m_bgen->heatmap[index_2d] -= alt_to_heat * t_alt / altitude_chill; + } + } + + return surface_max_y; +} + +void MapgenValleys::generateCaves(s16 max_stone_y, s16 large_cave_depth) +{ + if (max_stone_y < node_min.Y) + return; + + noise_cave1->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z); + noise_cave2->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z); + + PseudoRandom ps(blockseed + 72202); + + MapNode n_air(CONTENT_AIR); + MapNode n_lava(c_lava_source); + MapNode n_water(c_river_water_source); + + const v3s16 &em = vm->m_area.getExtent(); + + // Cave blend distance near YMIN, YMAX + const float massive_cave_blend = 128.f; + // noise threshold for massive caves + const float massive_cave_threshold = 0.6f; + // mct: 1 = small rare caves, 0.5 1/3rd ground volume, 0 = 1/2 ground volume. + + float yblmin = -mapgen_limit + massive_cave_blend * 1.5f; + float yblmax = massive_cave_depth - massive_cave_blend * 1.5f; + bool made_a_big_one = false; + + // Cache the tcave values as they only vary by altitude. + if (node_max.Y <= massive_cave_depth) { + noise_massive_caves->perlinMap3D(node_min.X, node_min.Y - 1, node_min.Z); + + for (s16 y = node_min.Y - 1; y <= node_max.Y; y++) { + float tcave = massive_cave_threshold; + + if (y < yblmin) { + float t = (yblmin - y) / massive_cave_blend; + tcave += MYSQUARE(t); + } else if (y > yblmax) { + float t = (y - yblmax) / massive_cave_blend; + tcave += MYSQUARE(t); + } + + tcave_cache[y - node_min.Y + 1] = tcave; + } + } + + // lava_depth varies between one and ten as you approach + // the bottom of the world. + s16 lava_depth = ceil((lava_max_height - node_min.Y + 1) * 10.f / mapgen_limit); + // This allows random lava spawns to be less common at the surface. + s16 lava_chance = MYCUBE(lava_features_lim) * lava_depth; + // water_depth varies between ten and one on the way down. + s16 water_depth = ceil((mapgen_limit - abs(node_min.Y) + 1) * 10.f / mapgen_limit); + // This allows random water spawns to be more common at the surface. + s16 water_chance = MYCUBE(water_features_lim) * water_depth; + + // Reduce the odds of overflows even further. + if (node_max.Y > water_level) { + lava_chance /= 3; + water_chance /= 3; + } + + u32 index_2d = 0; + for (s16 z = node_min.Z; z <= node_max.Z; z++) + for (s16 x = node_min.X; x <= node_max.X; x++, index_2d++) { + Biome *biome = (Biome *)m_bmgr->getRaw(biomemap[index_2d]); + bool tunnel_air_above = false; + bool is_under_river = false; + bool underground = false; + u32 index_data = vm->m_area.index(x, node_max.Y, z); + u32 index_3d = (z - node_min.Z) * zstride_1d + csize.Y * ystride + (x - node_min.X); + + // Dig caves on down loop to check for air above. + // Don't excavate the overgenerated stone at node_max.Y + 1, + // this creates a 'roof' over the tunnel, preventing light in + // tunnels at mapchunk borders when generating mapchunks upwards. + // This 'roof' is removed when the mapchunk above is generated. + for (s16 y = node_max.Y; y >= node_min.Y - 1; y--, + index_3d -= ystride, + vm->m_area.add_y(em, index_data, -1)) { + + float terrain = noise_terrain_height->result[index_2d]; + + // Saves some time. + if (y > terrain + 10) + continue; + + if (y < terrain - 40) + underground = true; + + // Dig massive caves. + if (node_max.Y <= massive_cave_depth + && noise_massive_caves->result[index_3d] + > tcave_cache[y - node_min.Y + 1]) { + vm->m_data[index_data] = n_air; + made_a_big_one = true; + continue; + } + + content_t c = vm->m_data[index_data].getContent(); + // Detect river water to place riverbed nodes in tunnels + if (c == biome->c_river_water) + is_under_river = true; + + float d1 = contour(noise_cave1->result[index_3d]); + float d2 = contour(noise_cave2->result[index_3d]); + + if (d1 * d2 > cave_width && ndef->get(c).is_ground_content) { + // in a tunnel + vm->m_data[index_data] = n_air; + tunnel_air_above = true; + } else if (c == biome->c_filler || c == biome->c_stone) { + if (tunnel_air_above) { + // at the tunnel floor + s16 sr = ps.range(0, 39); + u32 j = index_data; + vm->m_area.add_y(em, j, 1); + + if (sr > terrain - y) { + // Put biome nodes in tunnels near the surface + if (is_under_river) + vm->m_data[index_data] = MapNode(biome->c_riverbed); + else if (underground) + vm->m_data[index_data] = MapNode(biome->c_filler); + else + vm->m_data[index_data] = MapNode(biome->c_top); + } else if (sr < 3 && underground) { + sr = abs(ps.next()); + if (lava_features_lim > 0 && y <= lava_max_height + && c == biome->c_stone && sr < lava_chance) + vm->m_data[j] = n_lava; + + sr -= lava_chance; + + // If sr < 0 then we should have already placed lava -- + // don't immediately dump water on it. + if (water_features_lim > 0 && y <= cave_water_max_height + && sr >= 0 && sr < water_chance) + vm->m_data[j] = n_water; + } + } + + tunnel_air_above = false; + underground = true; + } else { + tunnel_air_above = false; + } + } + } + + if (node_max.Y <= large_cave_depth && !made_a_big_one) { + u32 bruises_count = ps.range(0, 2); + for (u32 i = 0; i < bruises_count; i++) { + CavesRandomWalk cave(ndef, &gennotify, seed, water_level, + c_water_source, c_lava_source, lava_max_height); + + cave.makeCave(vm, node_min, node_max, &ps, true, max_stone_y, heightmap); + } + } +} |