minetest/src/mapgen_valleys.cpp
paramat bb2ee54d3b Mapgen: Fix light in tunnels at mapchunk borders
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.
2016-03-14 08:45:01 +00:00

1019 lines
35 KiB
C++

/*
Minetest Valleys C
Copyright (C) 2010-2015 kwolekr, Ryan Kwolek <kwolekr@minetest.net>
Copyright (C) 2010-2015 paramat, Matt Gregory
Copyright (C) 2016 Duane Robertson <duane@duanerobertson.com>
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 "content_sao.h"
#include "nodedef.h"
#include "voxelalgorithms.h"
#include "settings.h" // For g_settings
#include "emerge.h"
#include "dungeongen.h"
#include "treegen.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, MapgenParams *params, EmergeManager *emerge)
: Mapgen(mapgenid, params, emerge)
{
this->m_emerge = emerge;
this->bmgr = emerge->biomemgr;
//// amount of elements to skip for the next index
//// for noise/height/biome maps (not vmanip)
this->ystride = csize.X;
this->zstride = csize.X * (csize.Y + 2);
this->biomemap = new u8[csize.X * csize.Z];
this->heightmap = new s16[csize.X * csize.Z];
this->heatmap = NULL;
this->humidmap = NULL;
this->map_gen_limit = MYMIN(MAX_MAP_GENERATION_LIMIT,
g_settings->getU16("map_generation_limit"));
MapgenValleysParams *sp = (MapgenValleysParams *)params->sparams;
this->spflags = sp->spflags;
this->humid_rivers = (spflags & MGVALLEYS_HUMID_RIVERS);
this->use_altitude_chill = (spflags & MGVALLEYS_ALT_CHILL);
this->altitude_chill = sp->altitude_chill;
this->humidity_adjust = params->np_biome_humidity.offset - 50.f;
this->large_cave_depth = sp->large_cave_depth;
this->lava_features_lim = rangelim(sp->lava_features, 0, 10);
this->massive_cave_depth = sp->massive_cave_depth;
this->river_depth_bed = sp->river_depth + 1.f;
this->river_size_factor = sp->river_size / 100.f;
this->water_features_lim = rangelim(sp->water_features, 0, 10);
// a small chance of overflows if the settings are very high
this->cave_water_max_height = water_level + MYMAX(0, water_features_lim - 4) * 50;
this->lava_max_height = water_level + MYMAX(0, lava_features_lim - 4) * 50;
tcave_cache = new float[csize.Y + 2];
//// 2D Terrain noise
noise_filler_depth = new Noise(&sp->np_filler_depth, seed, csize.X, csize.Z);
noise_inter_valley_slope = new Noise(&sp->np_inter_valley_slope, seed, csize.X, csize.Z);
noise_rivers = new Noise(&sp->np_rivers, seed, csize.X, csize.Z);
noise_terrain_height = new Noise(&sp->np_terrain_height, seed, csize.X, csize.Z);
noise_valley_depth = new Noise(&sp->np_valley_depth, seed, csize.X, csize.Z);
noise_valley_profile = new Noise(&sp->np_valley_profile, seed, csize.X, csize.Z);
//// 3D Terrain noise
noise_cave1 = new Noise(&sp->np_cave1, seed, csize.X, csize.Y + 2, csize.Z);
noise_cave2 = new Noise(&sp->np_cave2, seed, csize.X, csize.Y + 2, csize.Z);
noise_inter_valley_fill = new Noise(&sp->np_inter_valley_fill, seed, csize.X, csize.Y + 2, csize.Z);
noise_massive_caves = new Noise(&sp->np_massive_caves, seed, csize.X, csize.Y + 2, csize.Z);
//// Biome noise
noise_heat_blend = new Noise(&params->np_biome_heat_blend, seed, csize.X, csize.Z);
noise_heat = new Noise(&params->np_biome_heat, seed, csize.X, csize.Z);
noise_humidity_blend = new Noise(&params->np_biome_humidity_blend, seed, csize.X, csize.Z);
noise_humidity = new Noise(&params->np_biome_humidity, seed, csize.X, csize.Z);
//// Resolve nodes to be used
INodeDefManager *ndef = emerge->ndef;
c_cobble = ndef->getId("mapgen_cobble");
c_desert_stone = ndef->getId("mapgen_desert_stone");
c_dirt = ndef->getId("mapgen_dirt");
c_lava_source = ndef->getId("mapgen_lava_source");
c_mossycobble = ndef->getId("mapgen_mossycobble");
c_river_water_source = ndef->getId("mapgen_river_water_source");
c_sand = ndef->getId("mapgen_sand");
c_sandstonebrick = ndef->getId("mapgen_sandstonebrick");
c_sandstone = ndef->getId("mapgen_sandstone");
c_stair_cobble = ndef->getId("mapgen_stair_cobble");
c_stair_sandstonebrick = ndef->getId("mapgen_stair_sandstonebrick");
c_stone = ndef->getId("mapgen_stone");
c_water_source = ndef->getId("mapgen_water_source");
if (c_mossycobble == CONTENT_IGNORE)
c_mossycobble = c_cobble;
if (c_river_water_source == CONTENT_IGNORE)
c_river_water_source = c_water_source;
if (c_sand == CONTENT_IGNORE)
c_sand = c_stone;
if (c_sandstonebrick == CONTENT_IGNORE)
c_sandstonebrick = c_sandstone;
if (c_stair_cobble == CONTENT_IGNORE)
c_stair_cobble = c_cobble;
if (c_stair_sandstonebrick == CONTENT_IGNORE)
c_stair_sandstonebrick = c_sandstone;
}
MapgenValleys::~MapgenValleys()
{
delete noise_cave1;
delete noise_cave2;
delete noise_filler_depth;
delete noise_heat;
delete noise_heat_blend;
delete noise_humidity;
delete noise_humidity_blend;
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[] biomemap;
delete[] heightmap;
delete[] tcave_cache;
}
MapgenValleysParams::MapgenValleysParams()
{
spflags = MGVALLEYS_HUMID_RIVERS | MGVALLEYS_ALT_CHILL;
altitude_chill = 90; // The altitude at which temperature drops by 20C.
large_cave_depth = -33;
lava_features = 0; // How often water will occur in caves.
massive_cave_depth = -256; // highest altitude of massive caves
river_depth = 4; // How deep to carve river channels.
river_size = 5; // How wide to make rivers.
water_features = 0; // How often water will occur in caves.
np_cave1 = NoiseParams(0, 12, v3f(96, 96, 96), 52534, 4, 0.5, 2.0);
np_cave2 = NoiseParams(0, 12, v3f(96, 96, 96), 10325, 4, 0.5, 2.0);
np_filler_depth = NoiseParams(0.f, 1.2f, v3f(256, 256, 256), 1605, 3, 0.5f, 2.f);
np_inter_valley_fill = NoiseParams(0.f, 1.f, v3f(256, 512, 256), 1993, 6, 0.8f, 2.f);
np_inter_valley_slope = NoiseParams(0.5f, 0.5f, v3f(128, 128, 128), 746, 1, 1.f, 2.f);
np_rivers = NoiseParams(0.f, 1.f, v3f(256, 256, 256), -6050, 5, 0.6f, 2.f);
np_massive_caves = NoiseParams(0.f, 1.f, v3f(768, 256, 768), 59033, 6, 0.63f, 2.f);
np_terrain_height = NoiseParams(-10.f, 50.f, v3f(1024, 1024, 1024), 5202, 6, 0.4f, 2.f);
np_valley_depth = NoiseParams(5.f, 4.f, v3f(512, 512, 512), -1914, 1, 1.f, 2.f);
np_valley_profile = NoiseParams(0.6f, 0.5f, v3f(512, 512, 512), 777, 1, 1.f, 2.f);
}
void MapgenValleysParams::readParams(const Settings *settings)
{
settings->getFlagStrNoEx("mg_valleys_spflags", spflags, flagdesc_mapgen_valleys);
settings->getU16NoEx("mg_valleys_altitude_chill", altitude_chill);
settings->getS16NoEx("mg_valleys_large_cave_depth", large_cave_depth);
settings->getU16NoEx("mg_valleys_lava_features", lava_features);
settings->getS16NoEx("mg_valleys_massive_cave_depth", massive_cave_depth);
settings->getU16NoEx("mg_valleys_river_depth", river_depth);
settings->getU16NoEx("mg_valleys_river_size", river_size);
settings->getU16NoEx("mg_valleys_water_features", water_features);
settings->getNoiseParams("mg_valleys_np_cave1", np_cave1);
settings->getNoiseParams("mg_valleys_np_cave2", np_cave2);
settings->getNoiseParams("mg_valleys_np_filler_depth", np_filler_depth);
settings->getNoiseParams("mg_valleys_np_inter_valley_fill", np_inter_valley_fill);
settings->getNoiseParams("mg_valleys_np_inter_valley_slope", np_inter_valley_slope);
settings->getNoiseParams("mg_valleys_np_rivers", np_rivers);
settings->getNoiseParams("mg_valleys_np_massive_caves", np_massive_caves);
settings->getNoiseParams("mg_valleys_np_terrain_height", np_terrain_height);
settings->getNoiseParams("mg_valleys_np_valley_depth", np_valley_depth);
settings->getNoiseParams("mg_valleys_np_valley_profile", np_valley_profile);
}
void MapgenValleysParams::writeParams(Settings *settings) const
{
settings->setFlagStr("mg_valleys_spflags", spflags, flagdesc_mapgen_valleys, U32_MAX);
settings->setU16("mg_valleys_altitude_chill", altitude_chill);
settings->setS16("mg_valleys_large_cave_depth", large_cave_depth);
settings->setU16("mg_valleys_lava_features", lava_features);
settings->setS16("mg_valleys_massive_cave_depth", massive_cave_depth);
settings->setU16("mg_valleys_river_depth", river_depth);
settings->setU16("mg_valleys_river_size", river_size);
settings->setU16("mg_valleys_water_features", water_features);
settings->setNoiseParams("mg_valleys_np_cave1", np_cave1);
settings->setNoiseParams("mg_valleys_np_cave2", np_cave2);
settings->setNoiseParams("mg_valleys_np_filler_depth", np_filler_depth);
settings->setNoiseParams("mg_valleys_np_inter_valley_fill", np_inter_valley_fill);
settings->setNoiseParams("mg_valleys_np_inter_valley_slope", np_inter_valley_slope);
settings->setNoiseParams("mg_valleys_np_rivers", np_rivers);
settings->setNoiseParams("mg_valleys_np_massive_caves", np_massive_caves);
settings->setNoiseParams("mg_valleys_np_terrain_height", np_terrain_height);
settings->setNoiseParams("mg_valleys_np_valley_depth", np_valley_depth);
settings->setNoiseParams("mg_valleys_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 noise maps and base terrain height.
calculateNoise();
// Generate base terrain with initial heightmaps
s16 stone_surface_max_y = generateTerrain();
// Create biomemap at heightmap surface
bmgr->calcBiomes(csize.X, csize.Z, heatmap, humidmap, heightmap, biomemap);
// Actually place the biome-specific nodes
MgStoneType stone_type = generateBiomes(heatmap, humidmap);
// Cave creation.
if (flags & MG_CAVES)
generateCaves(stone_surface_max_y);
// Dungeon creation
if ((flags & MG_DUNGEONS) && node_max.Y < 50 && (stone_surface_max_y >= node_min.Y)) {
DungeonParams dp;
dp.np_rarity = nparams_dungeon_rarity;
dp.np_density = nparams_dungeon_density;
dp.np_wetness = nparams_dungeon_wetness;
dp.c_water = c_water_source;
if (stone_type == STONE) {
dp.c_cobble = c_cobble;
dp.c_moss = c_mossycobble;
dp.c_stair = c_stair_cobble;
dp.diagonal_dirs = false;
dp.mossratio = 3.f;
dp.holesize = v3s16(1, 2, 1);
dp.roomsize = v3s16(0, 0, 0);
dp.notifytype = GENNOTIFY_DUNGEON;
} else if (stone_type == DESERT_STONE) {
dp.c_cobble = c_desert_stone;
dp.c_moss = c_desert_stone;
dp.c_stair = c_desert_stone;
dp.diagonal_dirs = true;
dp.mossratio = 0.f;
dp.holesize = v3s16(2, 3, 2);
dp.roomsize = v3s16(2, 5, 2);
dp.notifytype = GENNOTIFY_TEMPLE;
} else if (stone_type == SANDSTONE) {
dp.c_cobble = c_sandstonebrick;
dp.c_moss = c_sandstonebrick;
dp.c_stair = c_sandstonebrick;
dp.diagonal_dirs = false;
dp.mossratio = 0.f;
dp.holesize = v3s16(2, 2, 2);
dp.roomsize = v3s16(2, 0, 2);
dp.notifytype = GENNOTIFY_DUNGEON;
}
DungeonGen dgen(this, &dp);
dgen.generate(blockseed, full_node_min, full_node_max);
}
// 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_filler_depth->perlinMap2D(x, z);
noise_heat_blend->perlinMap2D(x, z);
noise_heat->perlinMap2D(x, z);
noise_humidity_blend->perlinMap2D(x, z);
noise_humidity->perlinMap2D(x, z);
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++) {
noise_heat->result[index] += noise_heat_blend->result[index] + heat_offset;
noise_humidity->result[index] *= humidity_scale;
noise_humidity->result[index] += noise_humidity_blend->result[index];
}
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;
}
heatmap = noise_heat->result;
humidmap = noise_humidity->result;
}
// 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
else
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_sand(c_sand);
MapNode n_stone(c_stone);
MapNode n_water(c_water_source);
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 = noise_heat->result[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 = noise_humidity->result[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 + (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 (fabs(surface_delta) <= 0.5f && y > water_level && river) {
// river bottom
vm->m_data[index_data] = n_sand;
} else 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 {
vm->m_data[index_data] = n_air;
}
}
vm->m_area.add_y(em, index_data, 1);
index_3d += ystride;
}
// This happens if we're generating a chunk that doesn't
// contain the terrain surface, in which case, we need
// to set heightmap to a value outside of the chunk,
// to avoid confusing lua mods that use heightmap.
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 = noise_humidity->result[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;
noise_humidity->result[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.
noise_heat->result[index_2d] = t_heat;
else if (t_alt > 0.f)
noise_heat->result[index_2d] -= alt_to_heat * t_alt / altitude_chill;
}
}
return surface_max_y;
}
MgStoneType MapgenValleys::generateBiomes(float *heat_map, float *humidity_map)
{
v3s16 em = vm->m_area.getExtent();
u32 index = 0;
MgStoneType stone_type = STONE;
for (s16 z = node_min.Z; z <= node_max.Z; z++)
for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
Biome *biome = NULL;
u16 depth_top = 0;
u16 base_filler = 0;
u16 depth_water_top = 0;
u32 vi = vm->m_area.index(x, node_max.Y, z);
// Check node at base of mapchunk above, either a node of a previously
// generated mapchunk or if not, a node of overgenerated base terrain.
content_t c_above = vm->m_data[vi + em.X].getContent();
bool air_above = c_above == CONTENT_AIR;
bool water_above = (c_above == c_water_source || c_above == c_river_water_source);
// If there is air or water above enable top/filler placement, otherwise force
// nplaced to stone level by setting a number exceeding any possible filler depth.
u16 nplaced = (air_above || water_above) ? 0 : U16_MAX;
for (s16 y = node_max.Y; y >= node_min.Y; y--) {
content_t c = vm->m_data[vi].getContent();
// Biome is recalculated each time an upper surface is detected while
// working down a column. The selected biome then remains in effect for
// all nodes below until the next surface and biome recalculation.
// Biome is recalculated:
// 1. At the surface of stone below air or water.
// 2. At the surface of water below air.
// 3. When stone or water is detected but biome has not yet been calculated.
if ((c == c_stone && (air_above || water_above || !biome))
|| ((c == c_water_source || c == c_river_water_source)
&& (air_above || !biome))) {
// Both heat and humidity have already been adjusted for altitude.
biome = bmgr->getBiome(heat_map[index], humidity_map[index], y);
depth_top = biome->depth_top;
base_filler = MYMAX(depth_top
+ biome->depth_filler
+ noise_filler_depth->result[index], 0.f);
depth_water_top = biome->depth_water_top;
// Detect stone type for dungeons during every biome calculation.
// This is more efficient than detecting per-node and will not
// miss any desert stone or sandstone biomes.
if (biome->c_stone == c_desert_stone)
stone_type = DESERT_STONE;
else if (biome->c_stone == c_sandstone)
stone_type = SANDSTONE;
}
if (c == c_stone) {
content_t c_below = vm->m_data[vi - em.X].getContent();
// If the node below isn't solid, make this node stone, so that
// any top/filler nodes above are structurally supported.
// This is done by aborting the cycle of top/filler placement
// immediately by forcing nplaced to stone level.
if (c_below == CONTENT_AIR
|| c_below == c_water_source
|| c_below == c_river_water_source)
nplaced = U16_MAX;
if (nplaced < depth_top) {
vm->m_data[vi] = MapNode(biome->c_top);
nplaced++;
} else if (nplaced < base_filler) {
vm->m_data[vi] = MapNode(biome->c_filler);
nplaced++;
} else {
vm->m_data[vi] = MapNode(biome->c_stone);
}
air_above = false;
water_above = false;
} else if (c == c_water_source) {
vm->m_data[vi] = MapNode((y > (s32)(water_level - depth_water_top))
? biome->c_water_top : biome->c_water);
nplaced = 0; // Enable top/filler placement for next surface
air_above = false;
water_above = true;
} else if (c == c_river_water_source) {
vm->m_data[vi] = MapNode(biome->c_river_water);
nplaced = depth_top; // Enable filler placement for next surface
air_above = false;
water_above = true;
} else if (c == CONTENT_AIR) {
nplaced = 0; // Enable top/filler placement for next surface
air_above = true;
water_above = false;
} else { // Possible various nodes overgenerated from neighbouring mapchunks
nplaced = U16_MAX; // Disable top/filler placement
air_above = false;
water_above = false;
}
vm->m_area.add_y(em, vi, -1);
}
}
return stone_type;
}
void MapgenValleys::dustTopNodes()
{
if (node_max.Y < water_level)
return;
v3s16 em = vm->m_area.getExtent();
u32 index = 0;
for (s16 z = node_min.Z; z <= node_max.Z; z++)
for (s16 x = node_min.X; x <= node_max.X; x++, index++) {
Biome *biome = (Biome *)bmgr->getRaw(biomemap[index]);
if (biome->c_dust == CONTENT_IGNORE)
continue;
u32 vi = vm->m_area.index(x, full_node_max.Y, z);
content_t c_full_max = vm->m_data[vi].getContent();
s16 y_start;
if (c_full_max == CONTENT_AIR) {
y_start = full_node_max.Y - 1;
} else if (c_full_max == CONTENT_IGNORE) {
vi = vm->m_area.index(x, node_max.Y + 1, z);
content_t c_max = vm->m_data[vi].getContent();
if (c_max == CONTENT_AIR)
y_start = node_max.Y;
else
continue;
} else {
continue;
}
vi = vm->m_area.index(x, y_start, z);
for (s16 y = y_start; y >= node_min.Y - 1; y--) {
if (vm->m_data[vi].getContent() != CONTENT_AIR)
break;
vm->m_area.add_y(em, vi, -1);
}
content_t c = vm->m_data[vi].getContent();
if (!ndef->get(c).buildable_to && c != CONTENT_IGNORE && c != biome->c_dust) {
vm->m_area.add_y(em, vi, 1);
vm->m_data[vi] = MapNode(biome->c_dust);
}
}
}
void MapgenValleys::generateCaves(s16 max_stone_y)
{
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);
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 = -map_gen_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 + 1; 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 / map_gen_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((map_gen_limit - abs(node_min.Y) + 1) * 10.f / map_gen_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;
u32 index_3d = 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 *)bmgr->getRaw(biomemap[index_2d]);
bool air_above = false;
bool underground = false;
u32 index_data = vm->m_area.index(x, node_max.Y + 1, z);
index_3d = (z - node_min.Z) * zstride + (csize.Y + 1) * ystride + (x - node_min.X);
// Dig caves on down loop to check for air above.
for (s16 y = node_max.Y + 1;
y >= node_min.Y - 1;
y--, index_3d -= ystride, vm->m_area.add_y(em, index_data, -1)) {
// 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.
if (y > node_max.Y)
continue;
float terrain = noise_terrain_height->result[index_2d];
// Saves some time.
if (y > terrain + 10) {
air_above = true;
continue;
} else 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;
}
content_t c = vm->m_data[index_data].getContent();
float d1 = contour(noise_cave1->result[index_3d]);
float d2 = contour(noise_cave2->result[index_3d]);
// River water is not set as ground content
// in the default game. This can produce strange results
// when a cave undercuts a river. However, that's not for
// the mapgen to correct. Fix it in lua.
if (c == CONTENT_AIR) {
air_above = true;
} else if (d1 * d2 > 0.3f && ndef->get(c).is_ground_content) {
// in a cave
vm->m_data[index_data] = n_air;
air_above = true;
} else if (air_above && (c == biome->c_filler || c == biome->c_stone)) {
// at the cave floor
s16 sr = ps.range(0,39);
u32 j = index_data;
vm->m_area.add_y(em, j, 1);
if (sr > terrain - y) {
// Put dirt in caves near the surface.
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;
}
air_above = false;
underground = true;
} else if (c == biome->c_filler || c == biome->c_stone) {
air_above = false;
underground = true;
} else {
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++) {
CaveV5 cave(this, &ps);
cave.makeCave(node_min, node_max, max_stone_y);
}
}
}