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path: root/src/util/pointedthing.cpp
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/*
Minetest
Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>

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 "pointedthing.h"

#include "serialize.h"
#include "../exceptions.h"
#include <sstream>

PointedThing::PointedThing():
	type(POINTEDTHING_NOTHING),
	node_undersurface(0,0,0),
	node_abovesurface(0,0,0),
	object_id(-1)
{}

std::string PointedThing::dump() const
{
	std::ostringstream os(std::ios::binary);
	if(type == POINTEDTHING_NOTHING)
	{
		os<<"[nothing]";
	}
	else if(type == POINTEDTHING_NODE)
	{
		const v3s16 &u = node_undersurface;
		const v3s16 &a = node_abovesurface;
		os<<"[node under="<<u.X<<","<<u.Y<<","<<u.Z
			<< " above="<<a.X<<","<<a.Y<<","<<a.Z<<"]";
	}
	else if(type == POINTEDTHING_OBJECT)
	{
		os<<"[object "<<object_id<<"]";
	}
	else
	{
		os<<"[unknown PointedThing]";
	}
	return os.str();
}

void PointedThing::serialize(std::ostream &os) const
{
	writeU8(os, 0); // version
	writeU8(os, (u8)type);
	if(type == POINTEDTHING_NOTHING)
	{
		// nothing
	}
	else if(type == POINTEDTHING_NODE)
	{
		writeV3S16(os, node_undersurface);
		writeV3S16(os, node_abovesurface);
	}
	else if(type == POINTEDTHING_OBJECT)
	{
		writeS16(os, object_id);
	}
}

void PointedThing::deSerialize(std::istream &is)
{
	int version = readU8(is);
	if(version != 0) throw SerializationError(
			"unsupported PointedThing version");
	type = (PointedThingType) readU8(is);
	if(type == POINTEDTHING_NOTHING)
	{
		// nothing
	}
	else if(type == POINTEDTHING_NODE)
	{
		node_undersurface = readV3S16(is);
		node_abovesurface = readV3S16(is);
	}
	else if(type == POINTEDTHING_OBJECT)
	{
		object_id = readS16(is);
	}
	else
	{
		throw SerializationError(
			"unsupported PointedThingType");
	}
}

bool PointedThing::operator==(const PointedThing &pt2) const
{
	if(type != pt2.type)
		return false;
	if(type == POINTEDTHING_NODE)
	{
		if(node_undersurface != pt2.node_undersurface)
			return false;
		if(node_abovesurface != pt2.node_abovesurface)
			return false;
	}
	else if(type == POINTEDTHING_OBJECT)
	{
		if(object_id != pt2.object_id)
			return false;
	}
	return true;
}

bool PointedThing::operator!=(const PointedThing &pt2) const
{
	return !(*this == pt2);
}

/a> 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582
/*
Minetest
Copyright (C) 2010-2015 kwolekr, Ryan Kwolek <kwolekr@minetest.net>
Copyright (C) 2010-2015 paramat, Matt Gregory

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 "profiler.h" // For TimeTaker
#include "settings.h" // For g_settings
#include "emerge.h"
#include "dungeongen.h"
#include "cavegen.h"
#include "treegen.h"
#include "mg_biome.h"
#include "mg_ore.h"
#include "mg_decoration.h"
#include "mapgen_flat.h"


FlagDesc flagdesc_mapgen_flat[] = {
	{"lakes", MGFLAT_LAKES},
	{"hills", MGFLAT_HILLS},
	{NULL,    0}
};

///////////////////////////////////////////////////////////////////////////////////////


MapgenFlat::MapgenFlat(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;

	MapgenFlatParams *sp = (MapgenFlatParams *)params->sparams;
	this->spflags = sp->spflags;

	this->ground_level = sp->ground_level;
	this->large_cave_depth = sp->large_cave_depth;
	this->lake_threshold = sp->lake_threshold;
	this->lake_steepness = sp->lake_steepness;
	this->hill_threshold = sp->hill_threshold;
	this->hill_steepness = sp->hill_steepness;

	//// 2D noise
	noise_terrain      = new Noise(&sp->np_terrain,      seed, csize.X, csize.Z);
	noise_filler_depth = new Noise(&sp->np_filler_depth, seed, csize.X, csize.Z);

	//// 3D 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);

	//// Biome noise
	noise_heat           = new Noise(&params->np_biome_heat,           seed, csize.X, csize.Z);
	noise_humidity       = new Noise(&params->np_biome_humidity,       seed, csize.X, csize.Z);
	noise_heat_blend     = new Noise(&params->np_biome_heat_blend,     seed, csize.X, csize.Z);
	noise_humidity_blend = new Noise(&params->np_biome_humidity_blend, seed, csize.X, csize.Z);

	//// Resolve nodes to be used
	INodeDefManager *ndef = emerge->ndef;

	c_stone                = ndef->getId("mapgen_stone");
	c_water_source         = ndef->getId("mapgen_water_source");
	c_lava_source          = ndef->getId("mapgen_lava_source");
	c_desert_stone         = ndef->getId("mapgen_desert_stone");
	c_ice                  = ndef->getId("mapgen_ice");
	c_sandstone            = ndef->getId("mapgen_sandstone");

	c_cobble               = ndef->getId("mapgen_cobble");
	c_stair_cobble         = ndef->getId("mapgen_stair_cobble");
	c_mossycobble          = ndef->getId("mapgen_mossycobble");
	c_sandstonebrick       = ndef->getId("mapgen_sandstonebrick");
	c_stair_sandstonebrick = ndef->getId("mapgen_stair_sandstonebrick");

	if (c_ice == CONTENT_IGNORE)
		c_ice = CONTENT_AIR;
	if (c_mossycobble == CONTENT_IGNORE)
		c_mossycobble = c_cobble;
	if (c_stair_cobble == CONTENT_IGNORE)
		c_stair_cobble = c_cobble;
	if (c_sandstonebrick == CONTENT_IGNORE)
		c_sandstonebrick = c_sandstone;
	if (c_stair_sandstonebrick == CONTENT_IGNORE)
		c_stair_sandstonebrick = c_sandstone;
}


MapgenFlat::~MapgenFlat()
{
	delete noise_terrain;
	delete noise_filler_depth;
	delete noise_cave1;
	delete noise_cave2;

	delete noise_heat;
	delete noise_humidity;
	delete noise_heat_blend;
	delete noise_humidity_blend;

	delete[] heightmap;
	delete[] biomemap;
}


MapgenFlatParams::MapgenFlatParams()
{
	spflags = 0;

	ground_level = 8;
	large_cave_depth = -33;
	lake_threshold = -0.45;
	lake_steepness = 48.0;
	hill_threshold = 0.45;
	hill_steepness = 64.0;

	np_terrain      = NoiseParams(0, 1,   v3f(600, 600, 600), 7244,  5, 0.6, 2.0);
	np_filler_depth = NoiseParams(0, 1.2, v3f(150, 150, 150), 261,   3, 0.7, 2.0);
	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);
}


void MapgenFlatParams::readParams(const Settings *settings)
{
	settings->getFlagStrNoEx("mgflat_spflags", spflags, flagdesc_mapgen_flat);

	settings->getS16NoEx("mgflat_ground_level",     ground_level);
	settings->getS16NoEx("mgflat_large_cave_depth", large_cave_depth);
	settings->getFloatNoEx("mgflat_lake_threshold", lake_threshold);
	settings->getFloatNoEx("mgflat_lake_steepness", lake_steepness);
	settings->getFloatNoEx("mgflat_hill_threshold", hill_threshold);
	settings->getFloatNoEx("mgflat_hill_steepness", hill_steepness);

	settings->getNoiseParams("mgflat_np_terrain",      np_terrain);
	settings->getNoiseParams("mgflat_np_filler_depth", np_filler_depth);
	settings->getNoiseParams("mgflat_np_cave1",        np_cave1);
	settings->getNoiseParams("mgflat_np_cave2",        np_cave2);
}


void MapgenFlatParams::writeParams(Settings *settings) const
{
	settings->setFlagStr("mgflat_spflags", spflags, flagdesc_mapgen_flat, U32_MAX);

	settings->setS16("mgflat_ground_level",     ground_level);
	settings->setS16("mgflat_large_cave_depth", large_cave_depth);
	settings->setFloat("mgflat_lake_threshold", lake_threshold);
	settings->setFloat("mgflat_lake_steepness", lake_steepness);
	settings->setFloat("mgflat_hill_threshold", hill_threshold);
	settings->setFloat("mgflat_hill_steepness", hill_steepness);

	settings->setNoiseParams("mgflat_np_terrain",      np_terrain);
	settings->setNoiseParams("mgflat_np_filler_depth", np_filler_depth);
	settings->setNoiseParams("mgflat_np_cave1",        np_cave1);
	settings->setNoiseParams("mgflat_np_cave2",        np_cave2);
}


/////////////////////////////////////////////////////////////////


int MapgenFlat::getGroundLevelAtPoint(v2s16 p)
{
	float n_terrain = NoisePerlin2D(&noise_terrain->np, p.X, p.Y, seed);
	if ((spflags & MGFLAT_LAKES) && n_terrain < lake_threshold) {
		s16 depress = (lake_threshold - n_terrain) * lake_steepness;
		return ground_level - depress;
	} else if ((spflags & MGFLAT_HILLS) && n_terrain > hill_threshold) {
		s16 rise = (n_terrain - hill_threshold) * hill_steepness;
		return ground_level + rise;
	} else {
		return ground_level;
	}
}


void MapgenFlat::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);

	// Make some noise
	calculateNoise();

	// Generate base terrain, mountains, and ridges with initial heightmaps
	s16 stone_surface_max_y = generateTerrain();

	// Create heightmap
	updateHeightmap(node_min, node_max);

	// Create biomemap at heightmap surface
	bmgr->calcBiomes(csize.X, csize.Z, noise_heat->result,
		noise_humidity->result, heightmap, biomemap);

	// Actually place the biome-specific nodes
	MgStoneType stone_type = generateBiomes(noise_heat->result, noise_humidity->result);

	if (flags & MG_CAVES)
		generateCaves(stone_surface_max_y);

	if ((flags & MG_DUNGEONS) && (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     = 3.0;
			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     = 0.0;
			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     = 0.0;
			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();

	//printf("makeChunk: %dms\n", t.stop());

	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);

	//setLighting(node_min - v3s16(1, 0, 1) * MAP_BLOCKSIZE,
	//			node_max + v3s16(1, 0, 1) * MAP_BLOCKSIZE, 0xFF);

	this->generating = false;
}


void MapgenFlat::calculateNoise()
{
	//TimeTaker t("calculateNoise", NULL, PRECISION_MICRO);
	int x = node_min.X;
	int y = node_min.Y - 1;
	int z = node_min.Z;

	if ((spflags & MGFLAT_LAKES) || (spflags & MGFLAT_HILLS))
		noise_terrain->perlinMap2D(x, z);

	noise_filler_depth->perlinMap2D(x, z);

	if (flags & MG_CAVES) {
		noise_cave1->perlinMap3D(x, y, z);
		noise_cave2->perlinMap3D(x, y, z);
	}

	noise_heat->perlinMap2D(x, z);
	noise_humidity->perlinMap2D(x, z);
	noise_heat_blend->perlinMap2D(x, z);
	noise_humidity_blend->perlinMap2D(x, z);

	for (s32 i = 0; i < csize.X * csize.Z; i++) {
		noise_heat->result[i] += noise_heat_blend->result[i];
		noise_humidity->result[i] += noise_humidity_blend->result[i];
	}

	heatmap = noise_heat->result;
	humidmap = noise_humidity->result;
	//printf("calculateNoise: %dus\n", t.stop());
}


s16 MapgenFlat::generateTerrain()
{
	MapNode n_air(CONTENT_AIR);
	MapNode n_stone(c_stone);
	MapNode n_water(c_water_source);

	v3s16 em = vm->m_area.getExtent();
	s16 stone_surface_max_y = -MAX_MAP_GENERATION_LIMIT;
	u32 ni2d = 0;

	for (s16 z = node_min.Z; z <= node_max.Z; z++)
	for (s16 x = node_min.X; x <= node_max.X; x++, ni2d++) {
		s16 stone_level = ground_level;
		float n_terrain = 0.0f;

		if ((spflags & MGFLAT_LAKES) || (spflags & MGFLAT_HILLS))
			n_terrain = noise_terrain->result[ni2d];

		if ((spflags & MGFLAT_LAKES) && n_terrain < lake_threshold) {
			s16 depress = (lake_threshold - n_terrain) * lake_steepness;
			stone_level = ground_level - depress;
		} else if ((spflags & MGFLAT_HILLS) && n_terrain > hill_threshold) {
			s16 rise = (n_terrain - hill_threshold) * hill_steepness;
		 	stone_level = ground_level + rise;
		}

		u32 vi = vm->m_area.index(x, node_min.Y - 1, z);
		for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
			if (vm->m_data[vi].getContent() == CONTENT_IGNORE) {
				if (y <= stone_level) {
					vm->m_data[vi] = n_stone;
					if (y > stone_surface_max_y)
						stone_surface_max_y = y;
				} else if (y <= water_level) {
					vm->m_data[vi] = n_water;
				} else {
					vm->m_data[vi] = n_air;
				}
			}
			vm->m_area.add_y(em, vi, 1);
		}
	}

	return stone_surface_max_y;
}


MgStoneType MapgenFlat::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;

		// 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 && (air_above || !biome))) {
				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);
				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)
					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 == 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 MapgenFlat::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 MapgenFlat::generateCaves(s16 max_stone_y)
{
	if (max_stone_y >= node_min.Y) {
		u32 index = 0;

		for (s16 z = node_min.Z; z <= node_max.Z; z++)
		for (s16 y = node_min.Y - 1; y <= node_max.Y + 1; y++) {
			u32 vi = vm->m_area.index(node_min.X, y, z);
			for (s16 x = node_min.X; x <= node_max.X; x++, vi++, index++) {
				float d1 = contour(noise_cave1->result[index]);
				float d2 = contour(noise_cave2->result[index]);
				if (d1 * d2 > 0.3f) {
					content_t c = vm->m_data[vi].getContent();
					if (!ndef->get(c).is_ground_content || c == CONTENT_AIR)
						continue;

					vm->m_data[vi] = MapNode(CONTENT_AIR);
				}
			}
		}
	}

	if (node_max.Y > large_cave_depth)
		return;

	PseudoRandom ps(blockseed + 21343);
	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);
	}
}