minetest/src/mapgen_valleys.cpp
paramat 1eca9ecf7d Mapgen: Remove '#include treegen.h' from non-mgv6 mapgens
Only mgv6 uses the tree functions from treegen.cpp.
2017-04-05 07:30:00 +01:00

753 lines
26 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 "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
this->m_bgen = (BiomeGenOriginal *)biomegen;
BiomeParamsOriginal *bp = (BiomeParamsOriginal *)params->bparams;
this->spflags = params->spflags;
this->altitude_chill = params->altitude_chill;
this->large_cave_depth = params->large_cave_depth;
this->lava_features_lim = rangelim(params->lava_features, 0, 10);
this->massive_cave_depth = params->massive_cave_depth;
this->river_depth_bed = params->river_depth + 1.f;
this->river_size_factor = params->river_size / 100.f;
this->water_features_lim = rangelim(params->water_features, 0, 10);
this->cave_width = params->cave_width;
//// 2D Terrain noise
noise_filler_depth = new Noise(&params->np_filler_depth, seed, csize.X, csize.Z);
noise_inter_valley_slope = new Noise(&params->np_inter_valley_slope, seed, csize.X, csize.Z);
noise_rivers = new Noise(&params->np_rivers, seed, csize.X, csize.Z);
noise_terrain_height = new Noise(&params->np_terrain_height, seed, csize.X, csize.Z);
noise_valley_depth = new Noise(&params->np_valley_depth, seed, csize.X, csize.Z);
noise_valley_profile = new Noise(&params->np_valley_profile, seed, csize.X, csize.Z);
//// 3D Terrain noise
// 1-up 1-down overgeneration
noise_inter_valley_fill = new Noise(&params->np_inter_valley_fill, seed, csize.X, csize.Y + 2, csize.Z);
// 1-down overgeneraion
noise_cave1 = new Noise(&params->np_cave1, seed, csize.X, csize.Y + 1, csize.Z);
noise_cave2 = new Noise(&params->np_cave2, seed, csize.X, csize.Y + 1, csize.Z);
noise_massive_caves = new Noise(&params->np_massive_caves, seed, csize.X, csize.Y + 1, csize.Z);
this->humid_rivers = (spflags & MGVALLEYS_HUMID_RIVERS);
this->use_altitude_chill = (spflags & MGVALLEYS_ALT_CHILL);
this->humidity_adjust = bp->np_humidity.offset - 50.f;
// 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];
}
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()
{
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.
cave_width = 0.09;
np_cave1 = NoiseParams(0, 12, v3f(61, 61, 61), 52534, 3, 0.5, 2.0);
np_cave2 = NoiseParams(0, 12, v3f(67, 67, 67), 10325, 3, 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("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 stone_type = generateBiomes();
// 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, stone_type);
// 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
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_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 = 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);
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;
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;
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);
cave.makeCave(vm, node_min, node_max, &ps, true, max_stone_y, heightmap);
}
}
}