Readded and optimized mapgen V6

1 files changed, 1391 insertions, 0 deletions

diff --git a/src/mapgen_v6.cpp b/src/mapgen_v6.cpp
new file mode 100644
index 000000000..b1c2583ba
--- /dev/null
+++ b/src/mapgen_v6.cpp
@@ -0,0 +1,1391 @@
+/*
+Minetest-c55
+Copyright (C) 2010-2011 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 "mapgen.h"
+#include "voxel.h"
+#include "noise.h"
+#include "mapblock.h"
+#include "mapnode.h"
+#include "map.h"
+//#include "serverobject.h"
+#include "content_sao.h"
+#include "nodedef.h"
+#include "content_mapnode.h" // For content_mapnode_get_new_name
+#include "voxelalgorithms.h"
+#include "profiler.h"
+#include "settings.h" // For g_settings
+#include "main.h" // For g_profiler
+
+#define AVERAGE_MUD_AMOUNT 4
+
+
+NoiseParams nparams_v6_def_terrain_base =
+	{-AVERAGE_MUD_AMOUNT, 20.0, v3f(250.0, 250.0, 250.0), 82341, 5, 0.6};
+NoiseParams nparams_v6_def_terrain_higher =
+	{20.0, 16.0, v3f(500.0, 500.0, 500.0), 85309, 5, 0.6};
+NoiseParams nparams_v6_def_steepness =
+	{0.85, 0.5, v3f(125.0, 125.0, 125.0), -932, 5, 0.7};
+NoiseParams nparams_v6_def_height_select =
+	{0.5, 1.0, v3f(250.0, 250.0, 250.0), 4213, 5, 0.69};
+NoiseParams nparams_v6_def_trees =
+	{0.0, 1.0, v3f(125.0, 125.0, 125.0), 2, 4, 0.66};
+NoiseParams nparams_v6_def_mud =
+	{AVERAGE_MUD_AMOUNT, 2.0, v3f(200.0, 200.0, 200.0), 91013, 3, 0.55};
+NoiseParams nparams_v6_def_beach =
+	{0.0, 1.0, v3f(250.0, 250.0, 250.0), 59420, 3, 0.50};
+NoiseParams nparams_v6_def_biome =
+	{0.0, 1.0, v3f(250.0, 250.0, 250.0), 9130, 3, 0.50};
+//NoiseParams nparams_v6_def_cave =
+//	{6.0, 6.0, v3f(250.0, 250.0, 250.0), 34329, 3, 0.50};
+
+
+NoiseParams *np_terrain_base   = &nparams_v6_def_terrain_base;
+NoiseParams *np_terrain_higher = &nparams_v6_def_terrain_higher;
+NoiseParams *np_steepness      = &nparams_v6_def_steepness;
+NoiseParams *np_height_select  = &nparams_v6_def_height_select;
+NoiseParams *np_trees          = &nparams_v6_def_trees;
+NoiseParams *np_mud            = &nparams_v6_def_mud;
+NoiseParams *np_beach          = &nparams_v6_def_beach;
+NoiseParams *np_biome          = &nparams_v6_def_biome;
+//NoiseParams *np_cave           = &nparams_v6_def_cave;
+
+
+MapgenV6::MapgenV6(int mapgenid, u64 seed) {
+	this->generating  = false;
+	this->id       = mapgenid;
+	this->seed     = (int)seed;
+
+	this->water_level = 1;
+
+	this->csize   = v3s16(5, 5, 5) * MAP_BLOCKSIZE; /////////////////get this from config!
+	this->ystride = csize.X;
+
+	this->use_smooth_biome_trans = g_settings->getBool("mgv6_use_smooth_biome_trans");
+
+	noise_terrain_base   = new Noise(np_terrain_base,   seed, csize.X, csize.Y);
+	noise_terrain_higher = new Noise(np_terrain_higher, seed, csize.X, csize.Y);
+	noise_steepness      = new Noise(np_steepness,      seed, csize.X, csize.Y);
+	noise_height_select  = new Noise(np_height_select,  seed, csize.X, csize.Y);
+	noise_trees          = new Noise(np_trees,          seed, csize.X, csize.Y);
+	noise_mud            = new Noise(np_mud,            seed, csize.X, csize.Y);
+	noise_beach          = new Noise(np_beach,          seed, csize.X, csize.Y);
+	noise_biome          = new Noise(np_biome,          seed, csize.X, csize.Y);
+	//noise_cave           = new Noise(np_cave,           seed, csize.X, csize.Y);
+
+	map_terrain_base   = noise_terrain_base->result;
+	map_terrain_higher = noise_terrain_higher->result;
+	map_steepness      = noise_steepness->result;
+	map_height_select  = noise_height_select->result;
+	map_trees          = noise_trees->result;
+	map_mud            = noise_mud->result;
+	map_beach          = noise_beach->result;
+	map_biome          = noise_biome->result;
+	//map_cave           = noise_cave->result;
+}
+
+
+MapgenV6::~MapgenV6() {
+	delete noise_terrain_base;
+	delete noise_terrain_higher;
+	delete noise_steepness;
+	delete noise_height_select;
+	delete noise_trees;
+	delete noise_mud;
+	delete noise_beach;
+	delete noise_biome;
+	delete noise_cave;
+}
+
+
+/*
+	Some helper functions for the map generator
+*/
+
+#if 1
+// Returns Y one under area minimum if not found
+s16 MapgenV6::find_ground_level(VoxelManipulator &vmanip, v2s16 p2d,
+		INodeDefManager *ndef)
+{
+	v3s16 em = vmanip.m_area.getExtent();
+	s16 y_nodes_max = vmanip.m_area.MaxEdge.Y;
+	s16 y_nodes_min = vmanip.m_area.MinEdge.Y;
+	u32 i = vmanip.m_area.index(v3s16(p2d.X, y_nodes_max, p2d.Y));
+	s16 y;
+	for(y=y_nodes_max; y>=y_nodes_min; y--)
+	{
+		MapNode &n = vmanip.m_data[i];
+		if(ndef->get(n).walkable)
+			break;
+
+		vmanip.m_area.add_y(em, i, -1);
+	}
+	if(y >= y_nodes_min)
+		return y;
+	else
+		return y_nodes_min - 1;
+}
+
+// Returns Y one under area minimum if not found
+s16 MapgenV6::find_stone_level(VoxelManipulator &vmanip, v2s16 p2d,
+		INodeDefManager *ndef)
+{
+	v3s16 em = vmanip.m_area.getExtent();
+	s16 y_nodes_max = vmanip.m_area.MaxEdge.Y;
+	s16 y_nodes_min = vmanip.m_area.MinEdge.Y;
+	u32 i = vmanip.m_area.index(v3s16(p2d.X, y_nodes_max, p2d.Y));
+	s16 y;
+	content_t c_stone = ndef->getId("mapgen_stone");
+	content_t c_desert_stone = ndef->getId("mapgen_desert_stone");
+	for(y=y_nodes_max; y>=y_nodes_min; y--)
+	{
+		MapNode &n = vmanip.m_data[i];
+		content_t c = n.getContent();
+		if(c != CONTENT_IGNORE && (
+				c == c_stone || c == c_desert_stone))
+			break;
+
+		vmanip.m_area.add_y(em, i, -1);
+	}
+	if(y >= y_nodes_min)
+		return y;
+	else
+		return y_nodes_min - 1;
+}
+#endif
+
+void MapgenV6::make_tree(ManualMapVoxelManipulator &vmanip, v3s16 p0,
+		bool is_apple_tree, INodeDefManager *ndef)
+{
+	MapNode treenode(ndef->getId("mapgen_tree"));
+	MapNode leavesnode(ndef->getId("mapgen_leaves"));
+	MapNode applenode(ndef->getId("mapgen_apple"));
+
+	s16 trunk_h = myrand_range(4, 5);
+	v3s16 p1 = p0;
+	for(s16 ii=0; ii<trunk_h; ii++)
+	{
+		if(vmanip.m_area.contains(p1))
+			vmanip.m_data[vmanip.m_area.index(p1)] = treenode;
+		p1.Y++;
+	}
+
+	// p1 is now the last piece of the trunk
+	p1.Y -= 1;
+
+	VoxelArea leaves_a(v3s16(-2,-1,-2), v3s16(2,2,2));
+	//SharedPtr<u8> leaves_d(new u8[leaves_a.getVolume()]);
+	Buffer<u8> leaves_d(leaves_a.getVolume());
+	for(s32 i=0; i<leaves_a.getVolume(); i++)
+		leaves_d[i] = 0;
+
+	// Force leaves at near the end of the trunk
+	{
+		s16 d = 1;
+		for(s16 z=-d; z<=d; z++)
+		for(s16 y=-d; y<=d; y++)
+		for(s16 x=-d; x<=d; x++)
+		{
+			leaves_d[leaves_a.index(v3s16(x,y,z))] = 1;
+		}
+	}
+
+	// Add leaves randomly
+	for(u32 iii=0; iii<7; iii++)
+	{
+		s16 d = 1;
+
+		v3s16 p(
+			myrand_range(leaves_a.MinEdge.X, leaves_a.MaxEdge.X-d),
+			myrand_range(leaves_a.MinEdge.Y, leaves_a.MaxEdge.Y-d),
+			myrand_range(leaves_a.MinEdge.Z, leaves_a.MaxEdge.Z-d)
+		);
+
+		for(s16 z=0; z<=d; z++)
+		for(s16 y=0; y<=d; y++)
+		for(s16 x=0; x<=d; x++)
+		{
+			leaves_d[leaves_a.index(p+v3s16(x,y,z))] = 1;
+		}
+	}
+
+	// Blit leaves to vmanip
+	for(s16 z=leaves_a.MinEdge.Z; z<=leaves_a.MaxEdge.Z; z++)
+	for(s16 y=leaves_a.MinEdge.Y; y<=leaves_a.MaxEdge.Y; y++)
+	for(s16 x=leaves_a.MinEdge.X; x<=leaves_a.MaxEdge.X; x++)
+	{
+		v3s16 p(x,y,z);
+		p += p1;
+		if(vmanip.m_area.contains(p) == false)
+			continue;
+		u32 vi = vmanip.m_area.index(p);
+		if(vmanip.m_data[vi].getContent() != CONTENT_AIR
+				&& vmanip.m_data[vi].getContent() != CONTENT_IGNORE)
+			continue;
+		u32 i = leaves_a.index(x,y,z);
+		if(leaves_d[i] == 1) {
+			bool is_apple = myrand_range(0,99) < 10;
+			if(is_apple_tree && is_apple) {
+				vmanip.m_data[vi] = applenode;
+			} else {
+				vmanip.m_data[vi] = leavesnode;
+			}
+		}
+	}
+}
+
+
+/*
+	Noise functions. Make sure seed is mangled differently in each one.
+*/
+
+
+// Amount of trees per area in nodes
+double MapgenV6::tree_amount_2d(u64 seed, v2s16 p)
+{
+	/*double noise = noise2d_perlin(
+			0.5+(float)p.X/125, 0.5+(float)p.Y/125,
+			seed+2, 4, 0.66);*/
+	double noise = map_trees[(p.Y - node_min.Z) * ystride + (p.X - node_min.X)];
+	double zeroval = -0.39;
+	if(noise < zeroval)
+		return 0;
+	else
+		return 0.04 * (noise-zeroval) / (1.0-zeroval);
+}
+
+// Required by mapgen.h
+bool MapgenV6::block_is_underground(u64 seed, v3s16 blockpos)
+{
+	/*s16 minimum_groundlevel = (s16)get_sector_minimum_ground_level(
+			seed, v2s16(blockpos.X, blockpos.Z));*/
+	// Nah, this is just a heuristic, just return something
+	s16 minimum_groundlevel = water_level;
+
+	if(blockpos.Y*MAP_BLOCKSIZE + MAP_BLOCKSIZE <= minimum_groundlevel)
+		return true;
+	else
+		return false;
+}
+
+
+double MapgenV6::base_rock_level_2d(u64 seed, v2s16 p)
+{
+	int index = (p.Y - node_min.Z) * ystride + (p.X - node_min.X);
+
+	// The base ground level
+	/*double base = (double)WATER_LEVEL - (double)AVERAGE_MUD_AMOUNT
+			+ 20. * noise2d_perlin(
+			0.5+(float)p.X/250., 0.5+(float)p.Y/250.,
+			seed+82341, 5, 0.6);*/
+	double base = water_level + map_terrain_base[index];
+	//return base;
+//printf("%f ", base);
+//return base;
+	// Higher ground level
+	/*double higher = (double)WATER_LEVEL + 20. + 16. * noise2d_perlin(
+			0.5+(float)p.X/500., 0.5+(float)p.Y/500.,
+			seed+85039, 5, 0.6);*/
+	double higher = water_level + map_terrain_higher[index];
+
+	// Limit higher to at least base
+	if(higher < base)
+		higher = base;
+
+	// Steepness factor of cliffs
+	/*double b = 0.85 + 0.5 * noise2d_perlin(
+			0.5+(float)p.X/125., 0.5+(float)p.Y/125.,
+			seed-932, 5, 0.7);*/
+	double b = map_steepness[index];
+	b = rangelim(b, 0.0, 1000.0);
+	b = pow(b, 7);
+	b *= 5;
+	b = rangelim(b, 0.5, 1000.0);
+	// Values 1.5...100 give quite horrible looking slopes
+	if(b > 1.5 && b < 100.0){
+		if(b < 10.0)
+			b = 1.5;
+		else
+			b = 100.0;
+	}
+	//dstream<<"b="<<b<<std::endl;
+	//double b = 20;
+	//b = 0.25;
+
+	// Offset to more low
+	double a_off = -0.20;
+	// High/low selector
+	/*double a = (double)0.5 + b * (a_off + noise2d_perlin(
+			0.5+(float)p.X/250., 0.5+(float)p.Y/250.,
+			seed+4213, 5, 0.69));*/
+	double a = 0.5 + b * (a_off + map_height_select[index]);
+	// Limit
+	a = rangelim(a, 0.0, 1.0);
+
+	//dstream<<"a="<<a<<std::endl;
+
+	double h = base*(1.0-a) + higher*a;
+
+	return h;
+}
+
+s16 MapgenV6::find_ground_level_from_noise(u64 seed, v2s16 p2d, s16 precision)
+{
+	return base_rock_level_2d(seed, p2d) + AVERAGE_MUD_AMOUNT;
+}
+
+double MapgenV6::get_mud_add_amount(u64 seed, v2s16 p)
+{
+	/*return ((float)AVERAGE_MUD_AMOUNT + 2.0 * noise2d_perlin(
+			0.5+(float)p.X/200, 0.5+(float)p.Y/200,
+			seed+91013, 3, 0.55));*/
+	int index = (p.Y - node_min.Z) * ystride + (p.X - node_min.X);
+	return map_mud[index];
+}
+
+bool MapgenV6::get_have_beach(u64 seed, v2s16 p2d)
+{
+	// Determine whether to have sand here
+	/*double sandnoise = noise2d_perlin(
+			0.2+(float)p2d.X/250, 0.7+(float)p2d.Y/250,
+			seed+59420, 3, 0.50);*/
+	int index = (p2d.Y - node_min.Z) * ystride + (p2d.X - node_min.X);
+	double sandnoise = map_beach[index];
+
+	return (sandnoise > 0.15);
+}
+
+BiomeType MapgenV6::get_biome(u64 seed, v2s16 p2d)
+{
+	// Just do something very simple as for now
+	/*double d = noise2d_perlin(
+			0.6+(float)p2d.X/250, 0.2+(float)p2d.Y/250,
+			seed+9130, 3, 0.50);*/
+	int index = (p2d.Y - node_min.Z) * ystride + (p2d.X - node_min.X);
+	double d = map_biome[index];
+	if(d > 0.45)
+		return BT_DESERT;
+	if (use_smooth_biome_trans) {
+		if(d > 0.35 && (noise2d( p2d.X, p2d.Y, int(seed) ) + 1.0) > ( 0.45 - d ) * 20.0  )
+			return BT_DESERT;
+	}
+	return BT_NORMAL;
+};
+
+u32 MapgenV6::get_blockseed(u64 seed, v3s16 p)
+{
+	s32 x=p.X, y=p.Y, z=p.Z;
+	return (u32)(seed%0x100000000ULL) + z*38134234 + y*42123 + x*23;
+}
+
+#define VMANIP_FLAG_CAVE VOXELFLAG_CHECKED1
+
+void MapgenV6::makeChunk(BlockMakeData *data)
+{
+	if(data->no_op)
+	{
+		//dstream<<"makeBlock: no-op"<<std::endl;
+		return;
+	}
+
+	this->generating = true;
+
+	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);
+
+	INodeDefManager *ndef = data->nodedef;
+
+	// Hack: use minimum block coordinates for old code that assumes
+	// a single block
+	v3s16 blockpos = data->blockpos_requested;
+
+	/*dstream<<"makeBlock(): ("<<blockpos.X<<","<<blockpos.Y<<","
+			<<blockpos.Z<<")"<<std::endl;*/
+
+	v3s16 blockpos_min = data->blockpos_min;
+	v3s16 blockpos_max = data->blockpos_max;
+	v3s16 blockpos_full_min = blockpos_min - v3s16(1,1,1);
+	v3s16 blockpos_full_max = blockpos_max + v3s16(1,1,1);
+
+	ManualMapVoxelManipulator &vmanip = *(data->vmanip);
+	// Area of central chunk
+	node_min = blockpos_min*MAP_BLOCKSIZE;
+	node_max = (blockpos_max+v3s16(1,1,1))*MAP_BLOCKSIZE-v3s16(1,1,1);
+	// Full allocated area
+	v3s16 full_node_min = (blockpos_min-1)*MAP_BLOCKSIZE;
+	v3s16 full_node_max = (blockpos_max+2)*MAP_BLOCKSIZE-v3s16(1,1,1);
+
+	v3s16 central_area_size = node_max - node_min + v3s16(1,1,1);
+
+	const s16 max_spread_amount = MAP_BLOCKSIZE;
+
+	int volume_blocks = (blockpos_max.X - blockpos_min.X + 1)
+			* (blockpos_max.Y - blockpos_min.Y + 1)
+			* (blockpos_max.Z - blockpos_max.Z + 1);
+
+	int volume_nodes = volume_blocks *
+			MAP_BLOCKSIZE*MAP_BLOCKSIZE*MAP_BLOCKSIZE;
+
+	// Generated surface area
+	//double gen_area_nodes = MAP_BLOCKSIZE*MAP_BLOCKSIZE * rel_volume;
+
+	// Horribly wrong heuristic, but better than nothing
+	bool block_is_underground = (water_level > node_max.Y);
+
+	/*
+		Create a block-specific seed
+	*/
+	u32 blockseed = get_blockseed(data->seed, full_node_min);
+
+	/*
+		Make some noise
+	*/
+	{
+		int x = node_min.X;
+		int z = node_min.Z;
+
+		// Need to adjust for the original implementation's +.5 offset...
+		noise_terrain_base->perlinMap2D(
+			x + 0.5 * noise_terrain_base->np->spread.X,
+			z + 0.5 * noise_terrain_base->np->spread.Z);
+		noise_terrain_base->transformNoiseMap();
+
+		noise_terrain_higher->perlinMap2D(
+			x + 0.5 * noise_terrain_higher->np->spread.X,
+			z + 0.5 * noise_terrain_higher->np->spread.Z);
+		noise_terrain_higher->transformNoiseMap();
+
+		noise_steepness->perlinMap2D(
+			x + 0.5 * noise_steepness->np->spread.X,
+			z + 0.5 * noise_steepness->np->spread.Z);
+		noise_steepness->transformNoiseMap();
+
+		noise_height_select->perlinMap2D(
+			x + 0.5 * noise_height_select->np->spread.X,
+			z + 0.5 * noise_height_select->np->spread.Z);
+
+		noise_mud->perlinMap2D(
+			x + 0.5 * noise_mud->np->spread.X,
+			z + 0.5 * noise_mud->np->spread.Z);
+		noise_mud->transformNoiseMap();
+
+		noise_beach->perlinMap2D(
+			x + 0.2 * noise_beach->np->spread.X,
+			z + 0.7 * noise_beach->np->spread.Z);
+
+		noise_biome->perlinMap2D(
+			x + 0.6 * noise_biome->np->spread.X,
+			z + 0.2 * noise_biome->np->spread.Z);
+
+/*		noise_cave->perlinMap2D(
+			x + 0.5 * noise_cave->np->spread.X,
+			z + 0.5 * noise_cave->np->spread.Z);
+		noise_cave->transformNoiseMap();*/
+	}
+
+
+	/*
+		Cache some ground type values for speed
+	*/
+
+// Creates variables c_name=id and n_name=node
+#define CONTENT_VARIABLE(ndef, name)\
+	content_t c_##name = ndef->getId("mapgen_" #name);\
+	MapNode n_##name(c_##name);
+// Default to something else if was CONTENT_IGNORE
+#define CONTENT_VARIABLE_FALLBACK(name, dname)\
+	if(c_##name == CONTENT_IGNORE){\
+		c_##name = c_##dname;\
+		n_##name = n_##dname;\
+	}
+
+	CONTENT_VARIABLE(ndef, stone);
+	CONTENT_VARIABLE(ndef, air);
+	CONTENT_VARIABLE(ndef, water_source);
+	CONTENT_VARIABLE(ndef, dirt);
+	CONTENT_VARIABLE(ndef, sand);
+	CONTENT_VARIABLE(ndef, gravel);
+	CONTENT_VARIABLE(ndef, clay);
+	CONTENT_VARIABLE(ndef, lava_source);
+	CONTENT_VARIABLE(ndef, cobble);
+	CONTENT_VARIABLE(ndef, mossycobble);
+	CONTENT_VARIABLE(ndef, dirt_with_grass);
+	CONTENT_VARIABLE(ndef, junglegrass);
+	CONTENT_VARIABLE(ndef, stone_with_coal);
+	CONTENT_VARIABLE(ndef, stone_with_iron);
+	CONTENT_VARIABLE(ndef, mese);
+	CONTENT_VARIABLE(ndef, desert_sand);
+	CONTENT_VARIABLE_FALLBACK(desert_sand, sand);
+	CONTENT_VARIABLE(ndef, desert_stone);
+	CONTENT_VARIABLE_FALLBACK(desert_stone, stone);
+
+	// Maximum height of the stone surface and obstacles.
+	// This is used to guide the cave generation
+	s16 stone_surface_max_y = 0;
+
+	/*
+		Generate general ground level to full area
+	*/
+	{
+#if 1
+	TimeTaker timer1("Generating ground level");
+
+	for(s16 x=node_min.X; x<=node_max.X; x++)
+	for(s16 z=node_min.Z; z<=node_max.Z; z++)
+	{
+		// Node position
+		v2s16 p2d = v2s16(x,z);
+
+		/*
+			Skip of already generated
+		*/
+		/*{
+			v3s16 p(p2d.X, node_min.Y, p2d.Y);
+			if(vmanip.m_data[vmanip.m_area.index(p)].d != CONTENT_AIR)
+				continue;
+		}*/
+
+		// Ground height at this point
+		float surface_y_f = 0.0;
+
+		// Use perlin noise for ground height
+		surface_y_f = base_rock_level_2d(data->seed, p2d);
+
+		/*// Experimental stuff
+		{
+			float a = highlands_level_2d(data->seed, p2d);
+			if(a > surface_y_f)
+				surface_y_f = a;
+		}*/
+
+		// Convert to integer
+		s16 surface_y = (s16)surface_y_f;
+
+		// Log it
+		if(surface_y > stone_surface_max_y)
+			stone_surface_max_y = surface_y;
+
+		BiomeType bt = get_biome(data->seed, p2d);
+		/*
+			Fill ground with stone
+		*/
+		{
+			// Use fast index incrementing
+			v3s16 em = vmanip.m_area.getExtent();
+			u32 i = vmanip.m_area.index(v3s16(p2d.X, node_min.Y, p2d.Y));
+			for(s16 y=node_min.Y; y<=node_max.Y; y++)
+			{
+				if(vmanip.m_data[i].getContent() == CONTENT_IGNORE){
+					if(y <= surface_y){
+						if(y > water_level && bt == BT_DESERT)
+							vmanip.m_data[i] = n_desert_stone;
+						else
+							vmanip.m_data[i] = n_stone;
+					} else if(y <= water_level){
+						vmanip.m_data[i] = MapNode(c_water_source);
+					} else {
+						vmanip.m_data[i] = MapNode(c_air);
+					}
+				}
+				vmanip.m_area.add_y(em, i, 1);
+			}
+		}
+	}
+#endif
+
+	}//timer1
+
+	// Limit dirt flow area by 1 because mud is flown into neighbors.
+	assert(central_area_size.X == central_area_size.Z);
+	s16 mudflow_minpos = 0-max_spread_amount+1;
+	s16 mudflow_maxpos = central_area_size.X+max_spread_amount-2;
+
+	/*
+		Loop this part, it will make stuff look older and newer nicely
+	*/
+
+	double cave_amount = 6.0 + 6.0 * noise2d_perlin(
+			0.5+(double)node_min.X/250, 0.5+(double)node_min.Y/250,
+			data->seed+34329, 3, 0.50);
+
+	const u32 age_loops = 2;
+	for(u32 i_age=0; i_age<age_loops; i_age++)
+	{ // Aging loop
+	/******************************
+		BEGINNING OF AGING LOOP
+	******************************/
+
+#if 1
+	{
+	// 24ms @cs=8
+	//TimeTaker timer1("caves");
+
+	/*
+		Make caves (this code is relatively horrible)
+	*/
+	cave_amount = MYMAX(0.0, cave_amount);
+	u32 caves_count = cave_amount * volume_nodes / 50000;
+	u32 bruises_count = 1;
+	PseudoRandom ps(blockseed+21343);
+	PseudoRandom ps2(blockseed+1032);
+	if(ps.range(1, 6) == 1)
+		bruises_count = ps.range(0, ps.range(0, 2));
+	if(get_biome(data->seed, v2s16(node_min.X, node_min.Y)) == BT_DESERT){
+		caves_count /= 3;
+		bruises_count /= 3;
+	}
+	for(u32 jj=0; jj<caves_count+bruises_count; jj++)
+	{
+		bool large_cave = (jj >= caves_count);
+		s16 min_tunnel_diameter = 2;
+		s16 max_tunnel_diameter = ps.range(2,6);
+		int dswitchint = ps.range(1,14);
+		u16 tunnel_routepoints = 0;
+		int part_max_length_rs = 0;
+		if(large_cave){
+			part_max_length_rs = ps.range(2,4);
+			tunnel_routepoints = ps.range(5, ps.range(15,30));
+			min_tunnel_diameter = 5;
+			max_tunnel_diameter = ps.range(7, ps.range(8,24));
+		} else {
+			part_max_length_rs = ps.range(2,9);
+			tunnel_routepoints = ps.range(10, ps.range(15,30));
+		}
+		bool large_cave_is_flat = (ps.range(0,1) == 0);
+
+		v3f main_direction(0,0,0);
+
+		// Allowed route area size in nodes
+		v3s16 ar = central_area_size;
+
+		// Area starting point in nodes
+		v3s16 of = node_min;
+
+		// Allow a bit more
+		//(this should be more than the maximum radius of the tunnel)
+		s16 insure = 10;
+		s16 more = max_spread_amount - max_tunnel_diameter/2 - insure;
+		ar += v3s16(1,0,1) * more * 2;
+		of -= v3s16(1,0,1) * more;
+
+		s16 route_y_min = 0;
+		// Allow half a diameter + 7 over stone surface
+		s16 route_y_max = -of.Y + stone_surface_max_y + max_tunnel_diameter/2 + 7;
+
+		// Limit maximum to area
+		route_y_max = rangelim(route_y_max, 0, ar.Y-1);
+
+		if(large_cave)
+		{
+			s16 min = 0;
+			if(node_min.Y < water_level && node_max.Y > water_level)
+			{
+				min = water_level - max_tunnel_diameter/3 - of.Y;
+				route_y_max = water_level + max_tunnel_diameter/3 - of.Y;
+			}
+			route_y_min = ps.range(min, min + max_tunnel_diameter);
+			route_y_min = rangelim(route_y_min, 0, route_y_max);
+		}
+
+		s16 route_start_y_min = route_y_min;
+		s16 route_start_y_max = route_y_max;
+
+		route_start_y_min = rangelim(route_start_y_min, 0, ar.Y-1);
+		route_start_y_max = rangelim(route_start_y_max, route_start_y_min, ar.Y-1);
+
+		// Randomize starting position
+		v3f orp(
+			(float)(ps.next()%ar.X)+0.5,
+			(float)(ps.range(route_start_y_min, route_start_y_max))+0.5,
+			(float)(ps.next()%ar.Z)+0.5
+		);
+
+		v3s16 startp(orp.X, orp.Y, orp.Z);
+		startp += of;
+
+		MapNode airnode(CONTENT_AIR);
+		MapNode waternode(c_water_source);
+		MapNode lavanode(c_lava_source);
+
+		/*
+			Generate some tunnel starting from orp
+		*/
+
+		for(u16 j=0; j<tunnel_routepoints; j++)
+		{
+			if(j%dswitchint==0 && large_cave == false)
+			{
+				main_direction = v3f(
+					((float)(ps.next()%20)-(float)10)/10,
+					((float)(ps.next()%20)-(float)10)/30,
+					((float)(ps.next()%20)-(float)10)/10
+				);
+				main_direction *= (float)ps.range(0, 10)/10;
+			}
+
+			// Randomize size
+			s16 min_d = min_tunnel_diameter;
+			s16 max_d = max_tunnel_diameter;
+			s16 rs = ps.range(min_d, max_d);
+
+			// Every second section is rough
+			bool randomize_xz = (ps2.range(1,2) == 1);
+
+			v3s16 maxlen;
+			if(large_cave)
+			{
+				maxlen = v3s16(
+					rs*part_max_length_rs,
+					rs*part_max_length_rs/2,
+					rs*part_max_length_rs
+				);
+			}
+			else
+			{
+				maxlen = v3s16(
+					rs*part_max_length_rs,
+					ps.range(1, rs*part_max_length_rs),
+					rs*part_max_length_rs
+				);
+			}
+
+			v3f vec;
+
+			vec = v3f(
+				(float)(ps.next()%(maxlen.X*1))-(float)maxlen.X/2,
+				(float)(ps.next()%(maxlen.Y*1))-(float)maxlen.Y/2,
+				(float)(ps.next()%(maxlen.Z*1))-(float)maxlen.Z/2
+			);
+
+			// Jump downward sometimes
+			if(!large_cave && ps.range(0,12) == 0)
+			{
+				vec = v3f(
+					(float)(ps.next()%(maxlen.X*1))-(float)maxlen.X/2,
+					(float)(ps.next()%(maxlen.Y*2))-(float)maxlen.Y*2/2,
+					(float)(ps.next()%(maxlen.Z*1))-(float)maxlen.Z/2
+				);
+			}
+
+			/*if(large_cave){
+				v3f p = orp + vec;
+				s16 h = find_ground_level_clever(vmanip,
+						v2s16(p.X, p.Z), ndef);
+				route_y_min = h - rs/3;
+				route_y_max = h + rs;
+			}*/
+
+			vec += main_direction;
+
+			v3f rp = orp + vec;
+			if(rp.X < 0)
+				rp.X = 0;
+			else if(rp.X >= ar.X)
+				rp.X = ar.X-1;
+			if(rp.Y < route_y_min)
+				rp.Y = route_y_min;
+			else if(rp.Y >= route_y_max)
+				rp.Y = route_y_max-1;
+			if(rp.Z < 0)
+				rp.Z = 0;
+			else if(rp.Z >= ar.Z)
+				rp.Z = ar.Z-1;
+			vec = rp - orp;
+
+			for(float f=0; f<1.0; f+=1.0/vec.getLength())
+			{
+				v3f fp = orp + vec * f;
+				fp.X += 0.1*ps.range(-10,10);
+				fp.Z += 0.1*ps.range(-10,10);
+				v3s16 cp(fp.X, fp.Y, fp.Z);
+
+				s16 d0 = -rs/2;
+				s16 d1 = d0 + rs;
+				if(randomize_xz){
+					d0 += ps.range(-1,1);
+					d1 += ps.range(-1,1);
+				}
+				for(s16 z0=d0; z0<=d1; z0++)
+				{
+					s16 si = rs/2 - MYMAX(0, abs(z0)-rs/7-1);
+					for(s16 x0=-si-ps.range(0,1); x0<=si-1+ps.range(0,1); x0++)
+					{
+						s16 maxabsxz = MYMAX(abs(x0), abs(z0));
+						s16 si2 = rs/2 - MYMAX(0, maxabsxz-rs/7-1);
+						for(s16 y0=-si2; y0<=si2; y0++)
+						{
+							/*// Make better floors in small caves
+							if(y0 <= -rs/2 && rs<=7)
+								continue;*/
+							if(large_cave_is_flat){
+								// Make large caves not so tall
+								if(rs > 7 && abs(y0) >= rs/3)
+									continue;
+							}
+
+							s16 z = cp.Z + z0;
+							s16 y = cp.Y + y0;
+							s16 x = cp.X + x0;
+							v3s16 p(x,y,z);
+							p += of;
+
+							if(vmanip.m_area.contains(p) == false)
+								continue;
+
+							u32 i = vmanip.m_area.index(p);
+
+							if(large_cave)
+							{
+								if(full_node_min.Y < water_level &&
+									full_node_max.Y > water_level){
+									if(p.Y <= water_level)
+										vmanip.m_data[i] = waternode;
+									else
+										vmanip.m_data[i] = airnode;
+								} else if(full_node_max.Y < water_level){
+									if(p.Y < startp.Y - 2)
+										vmanip.m_data[i] = lavanode;
+									else
+										vmanip.m_data[i] = airnode;
+								} else {
+									vmanip.m_data[i] = airnode;
+								}
+							} else {
+								// Don't replace air or water or lava or ignore
+								if(vmanip.m_data[i].getContent() == CONTENT_IGNORE ||
+								vmanip.m_data[i].getContent() == CONTENT_AIR ||
+								vmanip.m_data[i].getContent() == c_water_source ||
+								vmanip.m_data[i].getContent() == c_lava_source)
+									continue;
+
+								vmanip.m_data[i] = airnode;
+
+								// Set tunnel flag
+								vmanip.m_flags[i] |= VMANIP_FLAG_CAVE;
+							}
+						}
+					}
+				}
+			}
+
+			orp = rp;
+		}
+
+	}
+
+	}//timer1
+#endif
+
+#if 1
+	{
+	// 15ms @cs=8
+	TimeTaker timer1("add mud");
+
+	/*
+		Add mud to the central chunk
+	*/
+
+	for(s16 x=node_min.X; x<=node_max.X; x++)
+	for(s16 z=node_min.Z; z<=node_max.Z; z++)
+	{
+		// Node position in 2d
+		v2s16 p2d = v2s16(x,z);
+
+		// Randomize mud amount
+		s16 mud_add_amount = get_mud_add_amount(data->seed, p2d) / 2.0 + 0.5;
+
+		// Find ground level
+		s16 surface_y = find_stone_level(vmanip, p2d, ndef);
+		// Handle area not found
+		if(surface_y == vmanip.m_area.MinEdge.Y - 1)
+			continue;
+
+		MapNode addnode(c_dirt);
+		BiomeType bt = get_biome(data->seed, p2d);
+
+		if(bt == BT_DESERT)
+			addnode = MapNode(c_desert_sand);
+
+		if(bt == BT_DESERT && surface_y + mud_add_amount <= water_level+1){
+			addnode = MapNode(c_sand);
+		} else if(mud_add_amount <= 0){
+			mud_add_amount = 1 - mud_add_amount;
+			addnode = MapNode(c_gravel);
+		} else if(bt == BT_NORMAL && get_have_beach(data->seed, p2d) &&
+				surface_y + mud_add_amount <= water_level+2){
+			addnode = MapNode(c_sand);
+		}
+
+		if(bt == BT_DESERT){
+			if(surface_y > 20){
+				mud_add_amount = MYMAX(0, mud_add_amount - (surface_y - 20)/5);
+			}
+		}
+
+		/*
+			If topmost node is grass, change it to mud.
+			It might be if it was flown to there from a neighboring
+			chunk and then converted.
+		*/
+		{
+			u32 i = vmanip.m_area.index(v3s16(p2d.X, surface_y, p2d.Y));
+			MapNode *n = &vmanip.m_data[i];
+			if(n->getContent() == c_dirt_with_grass)
+				*n = MapNode(c_dirt);
+		}
+
+		/*
+			Add mud on ground
+		*/
+		{
+			s16 mudcount = 0;
+			v3s16 em = vmanip.m_area.getExtent();
+			s16 y_start = surface_y+1;
+			u32 i = vmanip.m_area.index(v3s16(p2d.X, y_start, p2d.Y));
+			for(s16 y=y_start; y<=node_max.Y; y++)
+			{
+				if(mudcount >= mud_add_amount)
+					break;
+
+				MapNode &n = vmanip.m_data[i];
+				n = addnode;
+				mudcount++;
+
+				vmanip.m_area.add_y(em, i, 1);
+			}
+		}
+
+	}
+
+	}//timer1
+#endif
+
+	/*
+		Add blobs of dirt and gravel underground
+	*/
+	if(get_biome(data->seed, v2s16(node_min.X, node_min.Y)) == BT_NORMAL)
+	{
+	PseudoRandom pr(blockseed+983);
+	for(int i=0; i<volume_nodes/10/10/10; i++)
+	{
+		bool only_fill_cave = (myrand_range(0,1) != 0);
+		v3s16 size(
+			pr.range(1, 8),
+			pr.range(1, 8),
+			pr.range(1, 8)
+		);
+		v3s16 p0(
+			pr.range(node_min.X, node_max.X)-size.X/2,
+			pr.range(node_min.Y, node_max.Y)-size.Y/2,
+			pr.range(node_min.Z, node_max.Z)-size.Z/2
+		);
+		MapNode n1;
+		if(p0.Y > -32 && pr.range(0,1) == 0)
+			n1 = MapNode(c_dirt);
+		else
+			n1 = MapNode(c_gravel);
+		for(int x1=0; x1<size.X; x1++)
+		for(int y1=0; y1<size.Y; y1++)
+		for(int z1=0; z1<size.Z; z1++)
+		{
+			v3s16 p = p0 + v3s16(x1,y1,z1);
+			u32 i = vmanip.m_area.index(p);
+			if(!vmanip.m_area.contains(i))
+				continue;
+			// Cancel if not stone and not cave air
+			if(vmanip.m_data[i].getContent() != c_stone &&
+					!(vmanip.m_flags[i] & VMANIP_FLAG_CAVE))
+				continue;
+			if(only_fill_cave && !(vmanip.m_flags[i] & VMANIP_FLAG_CAVE))
+				continue;
+			vmanip.m_data[i] = n1;
+		}
+	}
+	}
+
+#if 1
+	{
+	// 340ms @cs=8
+	TimeTaker timer1("flow mud");
+
+	/*
+		Flow mud away from steep edges
+	*/
+
+	// Iterate a few times
+	for(s16 k=0; k<3; k++)
+	{
+
+	for(s16 x=mudflow_minpos; x<=mudflow_maxpos; x++)
+	for(s16 z=mudflow_minpos; z<=mudflow_maxpos; z++)
+	{
+		// Invert coordinates every 2nd iteration
+		if(k%2 == 0)
+		{
+			x = mudflow_maxpos - (x-mudflow_minpos);
+			z = mudflow_maxpos - (z-mudflow_minpos);
+		}
+
+		// Node position in 2d
+		v2s16 p2d = v2s16(node_min.X, node_min.Z) + v2s16(x,z);
+
+		v3s16 em = vmanip.m_area.getExtent();
+		u32 i = vmanip.m_area.index(v3s16(p2d.X, node_max.Y, p2d.Y));
+		s16 y=node_max.Y;
+
+		while(y >= node_min.Y)
+		{
+
+		for(;; y--)
+		{
+			MapNode *n = NULL;
+			// Find mud
+			for(; y>=node_min.Y; y--)
+			{
+				n = &vmanip.m_data[i];
+				//if(content_walkable(n->d))
+				//	break;
+				if(n->getContent() == c_dirt ||
+						n->getContent() == c_dirt_with_grass ||
+						n->getContent() == c_gravel)
+					break;
+
+				vmanip.m_area.add_y(em, i, -1);
+			}
+
+			// Stop if out of area
+			//if(vmanip.m_area.contains(i) == false)
+			if(y < node_min.Y)
+				break;
+
+			/*// If not mud, do nothing to it
+			MapNode *n = &vmanip.m_data[i];
+			if(n->d != CONTENT_MUD && n->d != CONTENT_GRASS)
+				continue;*/
+
+			if(n->getContent() == c_dirt ||
+					n->getContent() == c_dirt_with_grass)
+			{
+				// Make it exactly mud
+				n->setContent(c_dirt);
+
+				/*
+					Don't flow it if the stuff under it is not mud
+				*/
+				{
+					u32 i2 = i;
+					vmanip.m_area.add_y(em, i2, -1);
+					// Cancel if out of area
+					if(vmanip.m_area.contains(i2) == false)
+						continue;
+					MapNode *n2 = &vmanip.m_data[i2];
+					if(n2->getContent() != c_dirt &&
+							n2->getContent() != c_dirt_with_grass)
+						continue;
+				}
+			}
+
+			/*s16 recurse_count = 0;
+	mudflow_recurse:*/
+
+			v3s16 dirs4[4] = {
+				v3s16(0,0,1), // back
+				v3s16(1,0,0), // right
+				v3s16(0,0,-1), // front
+				v3s16(-1,0,0), // left
+			};
+
+			// Theck that upper is air or doesn't exist.
+			// Cancel dropping if upper keeps it in place
+			u32 i3 = i;
+			vmanip.m_area.add_y(em, i3, 1);
+			if(vmanip.m_area.contains(i3) == true
+					&& ndef->get(vmanip.m_data[i3]).walkable)
+			{
+				continue;
+			}
+
+			// Drop mud on side
+
+			for(u32 di=0; di<4; di++)
+			{
+				v3s16 dirp = dirs4[di];
+				u32 i2 = i;
+				// Move to side
+				vmanip.m_area.add_p(em, i2, dirp);
+				// Fail if out of area
+				if(vmanip.m_area.contains(i2) == false)
+					continue;
+				// Check that side is air
+				MapNode *n2 = &vmanip.m_data[i2];
+				if(ndef->get(*n2).walkable)
+					continue;
+				// Check that under side is air
+				vmanip.m_area.add_y(em, i2, -1);
+				if(vmanip.m_area.contains(i2) == false)
+					continue;
+				n2 = &vmanip.m_data[i2];
+				if(ndef->get(*n2).walkable)
+					continue;
+				/*// Check that under that is air (need a drop of 2)
+				vmanip.m_area.add_y(em, i2, -1);
+				if(vmanip.m_area.contains(i2) == false)
+					continue;
+				n2 = &vmanip.m_data[i2];
+				if(content_walkable(n2->d))
+					continue;*/
+				// Loop further down until not air
+				bool dropped_to_unknown = false;
+				do{
+					vmanip.m_area.add_y(em, i2, -1);
+					n2 = &vmanip.m_data[i2];
+					// if out of known area
+					if(vmanip.m_area.contains(i2) == false
+							|| n2->getContent() == CONTENT_IGNORE){
+						dropped_to_unknown = true;
+						break;
+					}
+				}while(ndef->get(*n2).walkable == false);
+				// Loop one up so that we're in air
+				vmanip.m_area.add_y(em, i2, 1);
+				n2 = &vmanip.m_data[i2];
+
+				bool old_is_water = (n->getContent() == c_water_source);
+				// Move mud to new place
+				if(!dropped_to_unknown) {
+					*n2 = *n;
+					// Set old place to be air (or water)
+					if(old_is_water)
+						*n = MapNode(c_water_source);
+					else
+						*n = MapNode(CONTENT_AIR);
+				}
+
+				// Done
+				break;
+			}
+		}
+		}
+	}
+
+	}
+
+	}//timer1
+#endif
+
+	} // Aging loop
+	/***********************
+		END OF AGING LOOP
+	************************/
+
+	/*
+		Add top and bottom side of water to transforming_liquid queue
+	*/
+
+	for(s16 x=full_node_min.X; x<=full_node_max.X; x++)
+	for(s16 z=full_node_min.Z; z<=full_node_max.Z; z++)
+	{
+		// Node position
+		v2s16 p2d(x,z);
+		{
+			bool water_found = false;
+			// Use fast index incrementing
+			v3s16 em = vmanip.m_area.getExtent();
+			u32 i = vmanip.m_area.index(v3s16(p2d.X, full_node_max.Y, p2d.Y));
+			for(s16 y=full_node_max.Y; y>=full_node_min.Y; y--)
+			{
+				if(y == full_node_max.Y){
+					water_found =
+						(vmanip.m_data[i].getContent() == c_water_source ||
+						vmanip.m_data[i].getContent() == c_lava_source);
+				}
+				else if(water_found == false)
+				{
+					if(vmanip.m_data[i].getContent() == c_water_source ||
+							vmanip.m_data[i].getContent() == c_lava_source)
+					{
+						v3s16 p = v3s16(p2d.X, y, p2d.Y);
+						data->transforming_liquid.push_back(p);
+						water_found = true;
+					}
+				}
+				else
+				{
+					// This can be done because water_found can only
+					// turn to true and end up here after going through
+					// a single block.
+					if(vmanip.m_data[i+1].getContent() != c_water_source ||
+							vmanip.m_data[i+1].getContent() != c_lava_source)
+					{
+						v3s16 p = v3s16(p2d.X, y+1, p2d.Y);
+						data->transforming_liquid.push_back(p);
+						water_found = false;
+					}
+				}
+
+				vmanip.m_area.add_y(em, i, -1);
+			}
+		}
+	}
+
+	/*
+		Grow grass
+	*/
+
+	for(s16 x=full_node_min.X; x<=full_node_max.X; x++)
+	for(s16 z=full_node_min.Z; z<=full_node_max.Z; z++)
+	{
+		// Node position in 2d
+		v2s16 p2d = v2s16(x,z);
+
+		/*
+			Find the lowest surface to which enough light ends up
+			to make grass grow.
+
+			Basically just wait until not air and not leaves.
+		*/
+		s16 surface_y = 0;
+		{
+			v3s16 em = vmanip.m_area.getExtent();
+			u32 i = vmanip.m_area.index(v3s16(p2d.X, node_max.Y, p2d.Y));
+			s16 y;
+			// Go to ground level
+			for(y=node_max.Y; y>=full_node_min.Y; y--)
+			{
+				MapNode &n = vmanip.m_data[i];
+				if(ndef->get(n).param_type != CPT_LIGHT
+						|| ndef->get(n).liquid_type != LIQUID_NONE)
+					break;
+				vmanip.m_area.add_y(em, i, -1);
+			}
+			if(y >= full_node_min.Y)
+				surface_y = y;
+			else
+				surface_y = full_node_min.Y;
+		}
+
+		u32 i = vmanip.m_area.index(p2d.X, surface_y, p2d.Y);
+		MapNode *n = &vmanip.m_data[i];
+		if(n->getContent() == c_dirt){
+			// Well yeah, this can't be overground...
+			if(surface_y < water_level - 20)
+				continue;
+			n->setContent(c_dirt_with_grass);
+		}
+	}
+
+	/*
+		Generate some trees
+	*/
+	assert(central_area_size.X == central_area_size.Z);
+	{
+		// Divide area into parts
+		s16 div = 8;
+		s16 sidelen = central_area_size.X / div;
+		double area = sidelen * sidelen;
+		for(s16 x0=0; x0<div; x0++)
+		for(s16 z0=0; z0<div; z0++)
+		{
+			// Center position of part of division
+			v2s16 p2d_center(
+				node_min.X + sidelen/2 + sidelen*x0,
+				node_min.Z + sidelen/2 + sidelen*z0
+			);
+			// Minimum edge of part of division
+			v2s16 p2d_min(
+				node_min.X + sidelen*x0,
+				node_min.Z + sidelen*z0
+			);
+			// Maximum edge of part of division
+			v2s16 p2d_max(
+				node_min.X + sidelen + sidelen*x0 - 1,
+				node_min.Z + sidelen + sidelen*z0 - 1
+			);
+			// Amount of trees
+			u32 tree_count = area * tree_amount_2d(data->seed, p2d_center);
+			// Put trees in random places on part of division
+			for(u32 i=0; i<tree_count; i++)
+			{
+				s16 x = myrand_range(p2d_min.X, p2d_max.X);
+				s16 z = myrand_range(p2d_min.Y, p2d_max.Y);
+				s16 y = find_ground_level(vmanip, v2s16(x,z), ndef);
+				// Don't make a tree under water level
+				if(y < water_level)
+					continue;
+				// Don't make a tree so high that it doesn't fit
+				if(y > node_max.Y - 6)
+					continue;
+				v3s16 p(x,y,z);
+				/*
+					Trees grow only on mud and grass
+				*/
+				{
+					u32 i = vmanip.m_area.index(v3s16(p));
+					MapNode *n = &vmanip.m_data[i];
+					if(n->getContent() != c_dirt
+							&& n->getContent() != c_dirt_with_grass)
+						continue;
+				}
+				p.Y++;
+				// Make a tree
+				make_tree(vmanip, p, false, ndef);
+			}
+		}
+	}
+
+
+	/*
+		Calculate lighting
+	*/
+	{
+	ScopeProfiler sp(g_profiler, "EmergeThread: mapgen lighting update",
+			SPT_AVG);
+	//VoxelArea a(node_min, node_max);
+	VoxelArea a(node_min-v3s16(1,0,1)*MAP_BLOCKSIZE,
+			node_max+v3s16(1,0,1)*MAP_BLOCKSIZE);
+	/*VoxelArea a(node_min-v3s16(1,0,1)*MAP_BLOCKSIZE/2,
+			node_max+v3s16(1,0,1)*MAP_BLOCKSIZE/2);*/
+	enum LightBank banks[2] = {LIGHTBANK_DAY, LIGHTBANK_NIGHT};
+	for(int i=0; i<2; i++)
+	{
+		enum LightBank bank = banks[i];
+
+		core::map<v3s16, bool> light_sources;
+		core::map<v3s16, u8> unlight_from;
+
+		voxalgo::clearLightAndCollectSources(vmanip, a, bank, ndef,
+				light_sources, unlight_from);
+
+		bool inexistent_top_provides_sunlight = !block_is_underground;
+		voxalgo::SunlightPropagateResult res = voxalgo::propagateSunlight(
+				vmanip, a, inexistent_top_provides_sunlight,
+				light_sources, ndef);
+		// TODO: Do stuff according to bottom_sunlight_valid
+
+		vmanip.unspreadLight(bank, unlight_from, light_sources, ndef);
+
+		vmanip.spreadLight(bank, light_sources, ndef);
+	}
+	}
+}