minetest/src/mapgen.cpp

/*
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 General Public License as published by
the Free Software Foundation; either version 2 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 General Public License for more details.

You should have received a copy of the GNU 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 "content_mapnode.h"
#include "noise.h"
#include "mapblock.h"
#include "map.h"
#include "mineral.h"
//#include "serverobject.h"
#include "content_sao.h"

namespace mapgen
{

/*
	Some helper functions for the map generator
*/

#if 0
static s16 find_ground_level(VoxelManipulator &vmanip, v2s16 p2d)
{
	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(content_walkable(n.d))
			break;

		vmanip.m_area.add_y(em, i, -1);
	}
	if(y >= y_nodes_min)
		return y;
	else
		return y_nodes_min;
}

static s16 find_ground_level_clever(VoxelManipulator &vmanip, v2s16 p2d)
{
	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(content_walkable(n.d)
				&& n.getContent() != CONTENT_TREE
				&& n.getContent() != CONTENT_LEAVES)
			break;

		vmanip.m_area.add_y(em, i, -1);
	}
	if(y >= y_nodes_min)
		return y;
	else
		return y_nodes_min;
}
#endif

static void make_tree(VoxelManipulator &vmanip, v3s16 p0)
{
	MapNode treenode(CONTENT_TREE);
	MapNode leavesnode(CONTENT_LEAVES);

	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)
			vmanip.m_data[vi] = leavesnode;
	}
}

static void make_jungletree(VoxelManipulator &vmanip, v3s16 p0)
{
	MapNode treenode(CONTENT_JUNGLETREE);
	MapNode leavesnode(CONTENT_LEAVES);

	for(s16 x=-1; x<=1; x++)
	for(s16 z=-1; z<=1; z++)
	{
		if(myrand_range(0, 2) == 0)
			continue;
		v3s16 p1 = p0 + v3s16(x,0,z);
		v3s16 p2 = p0 + v3s16(x,-1,z);
		if(vmanip.m_area.contains(p2)
				&& vmanip.m_data[vmanip.m_area.index(p2)] == CONTENT_AIR)
			vmanip.m_data[vmanip.m_area.index(p2)] = treenode;
		else if(vmanip.m_area.contains(p1))
			vmanip.m_data[vmanip.m_area.index(p1)] = treenode;
	}

	s16 trunk_h = myrand_range(8, 12);
	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(-3,-2,-3), v3s16(3,2,3));
	//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<30; 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)
			vmanip.m_data[vi] = leavesnode;
	}
}

void make_papyrus(VoxelManipulator &vmanip, v3s16 p0)
{
	MapNode papyrusnode(CONTENT_PAPYRUS);

	s16 trunk_h = myrand_range(2, 3);
	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)] = papyrusnode;
		p1.Y++;
	}
}

void make_cactus(VoxelManipulator &vmanip, v3s16 p0)
{
	MapNode cactusnode(CONTENT_CACTUS);

	s16 trunk_h = 3;
	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)] = cactusnode;
		p1.Y++;
	}
}

#if 0
static void make_randomstone(VoxelManipulator &vmanip, v3s16 p0)
{
	MapNode stonenode(CONTENT_STONE);

	s16 size = myrand_range(3, 6);
	
	VoxelArea stone_a(v3s16(-2,0,-2), v3s16(2,size,2));
	Buffer<u8> stone_d(stone_a.getVolume());
	for(s32 i=0; i<stone_a.getVolume(); i++)
		stone_d[i] = 0;

	// Force stone at bottom to make it usually touch the ground
	{
		for(s16 z=0; z<=0; z++)
		for(s16 y=0; y<=0; y++)
		for(s16 x=0; x<=0; x++)
		{
			stone_d[stone_a.index(v3s16(x,y,z))] = 1;
		}
	}

	// Generate from perlin noise
	for(s16 z=stone_a.MinEdge.Z; z<=stone_a.MaxEdge.Z; z++)
	for(s16 y=stone_a.MinEdge.Y; y<=stone_a.MaxEdge.Y; y++)
	for(s16 x=stone_a.MinEdge.X; x<=stone_a.MaxEdge.X; x++)
	{
		double d = noise3d_perlin((float)x/3.,(float)z/3.,(float)y/3.,
				p0.Z*4243+p0.Y*34+p0.X, 2, 0.5);
		if(z == stone_a.MinEdge.Z || z == stone_a.MaxEdge.Z)
			d -= 0.3;
		if(/*y == stone_a.MinEdge.Y ||*/ y == stone_a.MaxEdge.Y)
			d -= 0.3;
		if(x == stone_a.MinEdge.X || x == stone_a.MaxEdge.X)
			d -= 0.3;
		if(d > 0.0)
		{
			u32 vi = stone_a.index(v3s16(x,y,z));
			stone_d[vi] = 1;
		}
	}

	/*// Add stone randomly
	for(u32 iii=0; iii<7; iii++)
	{
		s16 d = 1;

		v3s16 p(
			myrand_range(stone_a.MinEdge.X, stone_a.MaxEdge.X-d),
			myrand_range(stone_a.MinEdge.Y, stone_a.MaxEdge.Y-d),
			myrand_range(stone_a.MinEdge.Z, stone_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++)
		{
			stone_d[stone_a.index(p+v3s16(x,y,z))] = 1;
		}
	}*/

	// Blit stone to vmanip
	for(s16 z=stone_a.MinEdge.Z; z<=stone_a.MaxEdge.Z; z++)
	for(s16 y=stone_a.MinEdge.Y; y<=stone_a.MaxEdge.Y; y++)
	for(s16 x=stone_a.MinEdge.X; x<=stone_a.MaxEdge.X; x++)
	{
		v3s16 p(x,y,z);
		p += p0;
		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 = stone_a.index(x,y,z);
		if(stone_d[i] == 1)
			vmanip.m_data[vi] = stonenode;
	}
}
#endif

#if 0
static void make_largestone(VoxelManipulator &vmanip, v3s16 p0)
{
	MapNode stonenode(CONTENT_STONE);

	s16 size = myrand_range(8, 16);
	
	VoxelArea stone_a(v3s16(-size/2,0,-size/2), v3s16(size/2,size,size/2));
	Buffer<u8> stone_d(stone_a.getVolume());
	for(s32 i=0; i<stone_a.getVolume(); i++)
		stone_d[i] = 0;

	// Force stone at bottom to make it usually touch the ground
	{
		for(s16 z=0; z<=0; z++)
		for(s16 y=0; y<=0; y++)
		for(s16 x=0; x<=0; x++)
		{
			stone_d[stone_a.index(v3s16(x,y,z))] = 1;
		}
	}

	// Generate from perlin noise
	for(s16 z=stone_a.MinEdge.Z; z<=stone_a.MaxEdge.Z; z++)
	for(s16 y=stone_a.MinEdge.Y; y<=stone_a.MaxEdge.Y; y++)
	for(s16 x=stone_a.MinEdge.X; x<=stone_a.MaxEdge.X; x++)
	{
		double d = 1.0;
		d += noise3d_perlin((float)x/10.,(float)z/10.,(float)y/10.,
				p0.Z*5123+p0.Y*2439+p0.X, 2, 0.5);
		double mid_z = (stone_a.MaxEdge.Z+stone_a.MinEdge.Z)/2;
		double mid_x = (stone_a.MaxEdge.X+stone_a.MinEdge.X)/2;
		double mid_y = (stone_a.MaxEdge.Y+stone_a.MinEdge.Y)/2;
		double dz = (double)z-mid_z;
		double dx = (double)x-mid_x;
		double dy = MYMAX(0, (double)y-mid_y);
		double r = sqrt(dz*dz+dx*dx+dy*dy);
		d /= (2*r/size)*2 + 0.01;
		if(d > 1.0)
		{
			u32 vi = stone_a.index(v3s16(x,y,z));
			stone_d[vi] = 1;
		}
	}

	/*// Add stone randomly
	for(u32 iii=0; iii<7; iii++)
	{
		s16 d = 1;

		v3s16 p(
			myrand_range(stone_a.MinEdge.X, stone_a.MaxEdge.X-d),
			myrand_range(stone_a.MinEdge.Y, stone_a.MaxEdge.Y-d),
			myrand_range(stone_a.MinEdge.Z, stone_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++)
		{
			stone_d[stone_a.index(p+v3s16(x,y,z))] = 1;
		}
	}*/

	// Blit stone to vmanip
	for(s16 z=stone_a.MinEdge.Z; z<=stone_a.MaxEdge.Z; z++)
	for(s16 y=stone_a.MinEdge.Y; y<=stone_a.MaxEdge.Y; y++)
	for(s16 x=stone_a.MinEdge.X; x<=stone_a.MaxEdge.X; x++)
	{
		v3s16 p(x,y,z);
		p += p0;
		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 = stone_a.index(x,y,z);
		if(stone_d[i] == 1)
			vmanip.m_data[vi] = stonenode;
	}
}
#endif

/*
	Dungeon making routines
*/

#define VMANIP_FLAG_DUNGEON_INSIDE VOXELFLAG_CHECKED1
#define VMANIP_FLAG_DUNGEON_PRESERVE VOXELFLAG_CHECKED2
#define VMANIP_FLAG_DUNGEON_UNTOUCHABLE (\
		VMANIP_FLAG_DUNGEON_INSIDE|VMANIP_FLAG_DUNGEON_PRESERVE)

static void make_room1(VoxelManipulator &vmanip, v3s16 roomsize, v3s16 roomplace)
{
	// Make +-X walls
	for(s16 z=0; z<roomsize.Z; z++)
	for(s16 y=0; y<roomsize.Y; y++)
	{
		{
			v3s16 p = roomplace + v3s16(0,y,z);
			if(vmanip.m_area.contains(p) == false)
				continue;
			u32 vi = vmanip.m_area.index(p);
			if(vmanip.m_flags[vi] & VMANIP_FLAG_DUNGEON_UNTOUCHABLE)
				continue;
			vmanip.m_data[vi] = MapNode(CONTENT_COBBLE);
		}
		{
			v3s16 p = roomplace + v3s16(roomsize.X-1,y,z);
			if(vmanip.m_area.contains(p) == false)
				continue;
			u32 vi = vmanip.m_area.index(p);
			if(vmanip.m_flags[vi] & VMANIP_FLAG_DUNGEON_UNTOUCHABLE)
				continue;
			vmanip.m_data[vi] = MapNode(CONTENT_COBBLE);
		}
	}
	
	// Make +-Z walls
	for(s16 x=0; x<roomsize.X; x++)
	for(s16 y=0; y<roomsize.Y; y++)
	{
		{
			v3s16 p = roomplace + v3s16(x,y,0);
			if(vmanip.m_area.contains(p) == false)
				continue;
			u32 vi = vmanip.m_area.index(p);
			if(vmanip.m_flags[vi] & VMANIP_FLAG_DUNGEON_UNTOUCHABLE)
				continue;
			vmanip.m_data[vi] = MapNode(CONTENT_COBBLE);
		}
		{
			v3s16 p = roomplace + v3s16(x,y,roomsize.Z-1);
			if(vmanip.m_area.contains(p) == false)
				continue;
			u32 vi = vmanip.m_area.index(p);
			if(vmanip.m_flags[vi] & VMANIP_FLAG_DUNGEON_UNTOUCHABLE)
				continue;
			vmanip.m_data[vi] = MapNode(CONTENT_COBBLE);
		}
	}
	
	// Make +-Y walls (floor and ceiling)
	for(s16 z=0; z<roomsize.Z; z++)
	for(s16 x=0; x<roomsize.X; x++)
	{
		{
			v3s16 p = roomplace + v3s16(x,0,z);
			if(vmanip.m_area.contains(p) == false)
				continue;
			u32 vi = vmanip.m_area.index(p);
			if(vmanip.m_flags[vi] & VMANIP_FLAG_DUNGEON_UNTOUCHABLE)
				continue;
			vmanip.m_data[vi] = MapNode(CONTENT_COBBLE);
		}
		{
			v3s16 p = roomplace + v3s16(x,roomsize.Y-1,z);
			if(vmanip.m_area.contains(p) == false)
				continue;
			u32 vi = vmanip.m_area.index(p);
			if(vmanip.m_flags[vi] & VMANIP_FLAG_DUNGEON_UNTOUCHABLE)
				continue;
			vmanip.m_data[vi] = MapNode(CONTENT_COBBLE);
		}
	}
	
	// Fill with air
	for(s16 z=1; z<roomsize.Z-1; z++)
	for(s16 y=1; y<roomsize.Y-1; y++)
	for(s16 x=1; x<roomsize.X-1; x++)
	{
		v3s16 p = roomplace + v3s16(x,y,z);
		if(vmanip.m_area.contains(p) == false)
			continue;
		u32 vi = vmanip.m_area.index(p);
		vmanip.m_flags[vi] |= VMANIP_FLAG_DUNGEON_UNTOUCHABLE;
		vmanip.m_data[vi] = MapNode(CONTENT_AIR);
	}
}

static void make_fill(VoxelManipulator &vmanip, v3s16 place, v3s16 size,
		u8 avoid_flags, MapNode n, u8 or_flags)
{
	for(s16 z=0; z<size.Z; z++)
	for(s16 y=0; y<size.Y; y++)
	for(s16 x=0; x<size.X; x++)
	{
		v3s16 p = place + v3s16(x,y,z);
		if(vmanip.m_area.contains(p) == false)
			continue;
		u32 vi = vmanip.m_area.index(p);
		if(vmanip.m_flags[vi] & avoid_flags)
			continue;
		vmanip.m_flags[vi] |= or_flags;
		vmanip.m_data[vi] = n;
	}
}

static void make_hole1(VoxelManipulator &vmanip, v3s16 place)
{
	make_fill(vmanip, place, v3s16(1,2,1), 0, MapNode(CONTENT_AIR),
			VMANIP_FLAG_DUNGEON_INSIDE);
}

static void make_door1(VoxelManipulator &vmanip, v3s16 doorplace, v3s16 doordir)
{
	make_hole1(vmanip, doorplace);
	// Place torch (for testing)
	//vmanip.m_data[vmanip.m_area.index(doorplace)] = MapNode(CONTENT_TORCH);
}

static v3s16 rand_ortho_dir(PseudoRandom &random)
{
	if(random.next()%2==0)
		return random.next()%2 ? v3s16(-1,0,0) : v3s16(1,0,0);
	else
		return random.next()%2 ? v3s16(0,0,-1) : v3s16(0,0,1);
}

static v3s16 turn_xz(v3s16 olddir, int t)
{
	v3s16 dir;
	if(t == 0)
	{
		// Turn right
		dir.X = olddir.Z;
		dir.Z = -olddir.X;
		dir.Y = olddir.Y;
	}
	else
	{
		// Turn left
		dir.X = -olddir.Z;
		dir.Z = olddir.X;
		dir.Y = olddir.Y;
	}
	return dir;
}

static v3s16 random_turn(PseudoRandom &random, v3s16 olddir)
{
	int turn = random.range(0,2);
	v3s16 dir;
	if(turn == 0)
	{
		// Go straight
		dir = olddir;
	}
	else if(turn == 1)
		// Turn right
		dir = turn_xz(olddir, 0);
	else
		// Turn left
		dir = turn_xz(olddir, 1);
	return dir;
}

static void make_corridor(VoxelManipulator &vmanip, v3s16 doorplace,
		v3s16 doordir, v3s16 &result_place, v3s16 &result_dir,
		PseudoRandom &random)
{
	make_hole1(vmanip, doorplace);
	v3s16 p0 = doorplace;
	v3s16 dir = doordir;
	u32 length;
	if(random.next()%2)
		length = random.range(1,13);
	else
		length = random.range(1,6);
	length = random.range(1,13);
	u32 partlength = random.range(1,13);
	u32 partcount = 0;
	s16 make_stairs = 0;
	if(random.next()%2 == 0 && partlength >= 3)
		make_stairs = random.next()%2 ? 1 : -1;
	for(u32 i=0; i<length; i++)
	{
		v3s16 p = p0 + dir;
		if(partcount != 0)
			p.Y += make_stairs;

		/*// If already empty
		if(vmanip.getNodeNoExNoEmerge(p).getContent()
				== CONTENT_AIR
		&& vmanip.getNodeNoExNoEmerge(p+v3s16(0,1,0)).getContent()
				== CONTENT_AIR)
		{
		}*/

		if(vmanip.m_area.contains(p) == true
				&& vmanip.m_area.contains(p+v3s16(0,1,0)) == true)
		{
			if(make_stairs)
			{
				make_fill(vmanip, p+v3s16(-1,-1,-1), v3s16(3,5,3),
						VMANIP_FLAG_DUNGEON_UNTOUCHABLE, MapNode(CONTENT_COBBLE), 0);
				make_fill(vmanip, p, v3s16(1,2,1), 0, MapNode(CONTENT_AIR),
						VMANIP_FLAG_DUNGEON_INSIDE);
				make_fill(vmanip, p-dir, v3s16(1,2,1), 0, MapNode(CONTENT_AIR),
						VMANIP_FLAG_DUNGEON_INSIDE);
			}
			else
			{
				make_fill(vmanip, p+v3s16(-1,-1,-1), v3s16(3,4,3),
						VMANIP_FLAG_DUNGEON_UNTOUCHABLE, MapNode(CONTENT_COBBLE), 0);
				make_hole1(vmanip, p);
				/*make_fill(vmanip, p, v3s16(1,2,1), 0, MapNode(CONTENT_AIR),
						VMANIP_FLAG_DUNGEON_INSIDE);*/
			}

			p0 = p;
		}
		else
		{
			// Can't go here, turn away
			dir = turn_xz(dir, random.range(0,1));
			make_stairs = -make_stairs;
			partcount = 0;
			partlength = random.range(1,length);
			continue;
		}

		partcount++;
		if(partcount >= partlength)
		{
			partcount = 0;
			
			dir = random_turn(random, dir);
			
			partlength = random.range(1,length);

			make_stairs = 0;
			if(random.next()%2 == 0 && partlength >= 3)
				make_stairs = random.next()%2 ? 1 : -1;
		}
	}
	result_place = p0;
	result_dir = dir;
}

class RoomWalker
{
public:

	RoomWalker(VoxelManipulator &vmanip_, v3s16 pos, PseudoRandom &random):
			vmanip(vmanip_),
			m_pos(pos),
			m_random(random)
	{
		randomizeDir();
	}

	void randomizeDir()
	{
		m_dir = rand_ortho_dir(m_random);
	}

	void setPos(v3s16 pos)
	{
		m_pos = pos;
	}

	void setDir(v3s16 dir)
	{
		m_dir = dir;
	}
	
	bool findPlaceForDoor(v3s16 &result_place, v3s16 &result_dir)
	{
		for(u32 i=0; i<100; i++)
		{
			v3s16 p = m_pos + m_dir;
			v3s16 p1 = p + v3s16(0,1,0);
			if(vmanip.m_area.contains(p) == false
					|| vmanip.m_area.contains(p1) == false
					|| i % 4 == 0)
			{
				randomizeDir();
				continue;
			}
			if(vmanip.getNodeNoExNoEmerge(p).getContent()
					== CONTENT_COBBLE
			&& vmanip.getNodeNoExNoEmerge(p1).getContent()
					== CONTENT_COBBLE)
			{
				// Found wall, this is a good place!
				result_place = p;
				result_dir = m_dir;
				// Randomize next direction
				randomizeDir();
				return true;
			}
			/*
				Determine where to move next
			*/
			// Jump one up if the actual space is there
			if(vmanip.getNodeNoExNoEmerge(p+v3s16(0,0,0)).getContent()
					== CONTENT_COBBLE
			&& vmanip.getNodeNoExNoEmerge(p+v3s16(0,1,0)).getContent()
					== CONTENT_AIR
			&& vmanip.getNodeNoExNoEmerge(p+v3s16(0,2,0)).getContent()
					== CONTENT_AIR)
				p += v3s16(0,1,0);
			// Jump one down if the actual space is there
			if(vmanip.getNodeNoExNoEmerge(p+v3s16(0,1,0)).getContent()
					== CONTENT_COBBLE
			&& vmanip.getNodeNoExNoEmerge(p+v3s16(0,0,0)).getContent()
					== CONTENT_AIR
			&& vmanip.getNodeNoExNoEmerge(p+v3s16(0,-1,0)).getContent()
					== CONTENT_AIR)
				p += v3s16(0,-1,0);
			// Check if walking is now possible
			if(vmanip.getNodeNoExNoEmerge(p).getContent()
					!= CONTENT_AIR
			|| vmanip.getNodeNoExNoEmerge(p+v3s16(0,1,0)).getContent()
					!= CONTENT_AIR)
			{
				// Cannot continue walking here
				randomizeDir();
				continue;
			}
			// Move there
			m_pos = p;
		}
		return false;
	}

	bool findPlaceForRoomDoor(v3s16 roomsize, v3s16 &result_doorplace,
			v3s16 &result_doordir, v3s16 &result_roomplace)
	{
		for(s16 trycount=0; trycount<30; trycount++)
		{
			v3s16 doorplace;
			v3s16 doordir;
			bool r = findPlaceForDoor(doorplace, doordir);
			if(r == false)
				continue;
			v3s16 roomplace;
			// X east, Z north, Y up
#if 1
			if(doordir == v3s16(1,0,0)) // X+
				roomplace = doorplace +
						v3s16(0,-1,m_random.range(-roomsize.Z+2,-2));
			if(doordir == v3s16(-1,0,0)) // X-
				roomplace = doorplace +
						v3s16(-roomsize.X+1,-1,m_random.range(-roomsize.Z+2,-2));
			if(doordir == v3s16(0,0,1)) // Z+
				roomplace = doorplace +
						v3s16(m_random.range(-roomsize.X+2,-2),-1,0);
			if(doordir == v3s16(0,0,-1)) // Z-
				roomplace = doorplace +
						v3s16(m_random.range(-roomsize.X+2,-2),-1,-roomsize.Z+1);
#endif
#if 0
			if(doordir == v3s16(1,0,0)) // X+
				roomplace = doorplace + v3s16(0,-1,-roomsize.Z/2);
			if(doordir == v3s16(-1,0,0)) // X-
				roomplace = doorplace + v3s16(-roomsize.X+1,-1,-roomsize.Z/2);
			if(doordir == v3s16(0,0,1)) // Z+
				roomplace = doorplace + v3s16(-roomsize.X/2,-1,0);
			if(doordir == v3s16(0,0,-1)) // Z-
				roomplace = doorplace + v3s16(-roomsize.X/2,-1,-roomsize.Z+1);
#endif
			
			// Check fit
			bool fits = true;
			for(s16 z=1; z<roomsize.Z-1; z++)
			for(s16 y=1; y<roomsize.Y-1; y++)
			for(s16 x=1; x<roomsize.X-1; x++)
			{
				v3s16 p = roomplace + v3s16(x,y,z);
				if(vmanip.m_area.contains(p) == false)
				{
					fits = false;
					break;
				}
				if(vmanip.m_flags[vmanip.m_area.index(p)]
						& VMANIP_FLAG_DUNGEON_INSIDE)
				{
					fits = false;
					break;
				}
			}
			if(fits == false)
			{
				// Find new place
				continue;
			}
			result_doorplace = doorplace;
			result_doordir = doordir;
			result_roomplace = roomplace;
			return true;
		}
		return false;
	}

private:
	VoxelManipulator &vmanip;
	v3s16 m_pos;
	v3s16 m_dir;
	PseudoRandom &m_random;
};

static void make_dungeon1(VoxelManipulator &vmanip, PseudoRandom &random)
{
	v3s16 areasize = vmanip.m_area.getExtent();
	v3s16 roomsize;
	v3s16 roomplace;
	
	/*
		Find place for first room
	*/
	bool fits = false;
	for(u32 i=0; i<100; i++)
	{
		roomsize = v3s16(random.range(4,8),random.range(4,6),random.range(4,8));
		roomplace = vmanip.m_area.MinEdge + v3s16(
				random.range(0,areasize.X-roomsize.X-1),
				random.range(0,areasize.Y-roomsize.Y-1),
				random.range(0,areasize.Z-roomsize.Z-1));
		/*
			Check that we're not putting the room to an unknown place,
			otherwise it might end up floating in the air
		*/
		fits = true;
		for(s16 z=1; z<roomsize.Z-1; z++)
		for(s16 y=1; y<roomsize.Y-1; y++)
		for(s16 x=1; x<roomsize.X-1; x++)
		{
			v3s16 p = roomplace + v3s16(x,y,z);
			u32 vi = vmanip.m_area.index(p);
			if(vmanip.m_flags[vi] & VMANIP_FLAG_DUNGEON_INSIDE)
			{
				fits = false;
				break;
			}
			if(vmanip.m_data[vi].getContent() == CONTENT_IGNORE)
			{
				fits = false;
				break;
			}
		}
		if(fits)
			break;
	}
	// No place found
	if(fits == false)
		return;
	
	/*
		Stores the center position of the last room made, so that
		a new corridor can be started from the last room instead of
		the new room, if chosen so.
	*/
	v3s16 last_room_center = roomplace+v3s16(roomsize.X/2,1,roomsize.Z/2);
	
	u32 room_count = random.range(2,7);
	for(u32 i=0; i<room_count; i++)
	{
		// Make a room to the determined place
		make_room1(vmanip, roomsize, roomplace);
		
		v3s16 room_center = roomplace + v3s16(roomsize.X/2,1,roomsize.Z/2);

		// Place torch at room center (for testing)
		//vmanip.m_data[vmanip.m_area.index(room_center)] = MapNode(CONTENT_TORCH);

		// Quit if last room
		if(i == room_count-1)
			break;
		
		// Determine walker start position

		bool start_in_last_room = (random.range(0,2)!=0);
		//bool start_in_last_room = true;

		v3s16 walker_start_place;

		if(start_in_last_room)
		{
			walker_start_place = last_room_center;
		}
		else
		{
			walker_start_place = room_center;
			// Store center of current room as the last one
			last_room_center = room_center;
		}
		
		// Create walker and find a place for a door
		RoomWalker walker(vmanip, walker_start_place, random);
		v3s16 doorplace;
		v3s16 doordir;
		bool r = walker.findPlaceForDoor(doorplace, doordir);
		if(r == false)
			return;
		
		if(random.range(0,1)==0)
			// Make the door
			make_door1(vmanip, doorplace, doordir);
		else
			// Don't actually make a door
			doorplace -= doordir;
		
		// Make a random corridor starting from the door
		v3s16 corridor_end;
		v3s16 corridor_end_dir;
		make_corridor(vmanip, doorplace, doordir, corridor_end,
				corridor_end_dir, random);
		
		// Find a place for a random sized room
		roomsize = v3s16(random.range(4,8),random.range(4,6),random.range(4,8));
		walker.setPos(corridor_end);
		walker.setDir(corridor_end_dir);
		r = walker.findPlaceForRoomDoor(roomsize, doorplace, doordir, roomplace);
		if(r == false)
			return;

		if(random.range(0,1)==0)
			// Make the door
			make_door1(vmanip, doorplace, doordir);
		else
			// Don't actually make a door
			roomplace -= doordir;
		
	}
}

static void make_nc(VoxelManipulator &vmanip, PseudoRandom &random)
{
	v3s16 dir;
	u8 facedir_i = 0;
	s32 r = random.range(0, 3);
	if(r == 0){
		dir = v3s16( 1, 0, 0);
		facedir_i = 3;
	}
	if(r == 1){
		dir = v3s16(-1, 0, 0);
		facedir_i = 1;
	}
	if(r == 2){
		dir = v3s16( 0, 0, 1);
		facedir_i = 2;
	}
	if(r == 3){
		dir = v3s16( 0, 0,-1);
		facedir_i = 0;
	}
	v3s16 p = vmanip.m_area.MinEdge + v3s16(
			16+random.range(0,15),
			16+random.range(0,15),
			16+random.range(0,15));
	vmanip.m_data[vmanip.m_area.index(p)] = MapNode(CONTENT_NC, facedir_i);
	u32 length = random.range(3,15);
	for(u32 j=0; j<length; j++)
	{
		p -= dir;
		vmanip.m_data[vmanip.m_area.index(p)] = MapNode(CONTENT_NC_RB);
	}
}

/*
	Noise functions. Make sure seed is mangled differently in each one.
*/

/*
	Scaling the output of the noise function affects the overdrive of the
	contour function, which affects the shape of the output considerably.
*/
#define CAVE_NOISE_SCALE 12.0
//#define CAVE_NOISE_SCALE 10.0
//#define CAVE_NOISE_SCALE 7.5
//#define CAVE_NOISE_SCALE 5.0
//#define CAVE_NOISE_SCALE 1.0

//#define CAVE_NOISE_THRESHOLD (2.5/CAVE_NOISE_SCALE)
#define CAVE_NOISE_THRESHOLD (1.5/CAVE_NOISE_SCALE)

NoiseParams get_cave_noise1_params(u64 seed)
{
	/*return NoiseParams(NOISE_PERLIN_CONTOUR, seed+52534, 5, 0.7,
			200, CAVE_NOISE_SCALE);*/
	/*return NoiseParams(NOISE_PERLIN_CONTOUR, seed+52534, 4, 0.7,
			100, CAVE_NOISE_SCALE);*/
	/*return NoiseParams(NOISE_PERLIN_CONTOUR, seed+52534, 5, 0.6,
			100, CAVE_NOISE_SCALE);*/
	/*return NoiseParams(NOISE_PERLIN_CONTOUR, seed+52534, 5, 0.3,
			100, CAVE_NOISE_SCALE);*/
	return NoiseParams(NOISE_PERLIN_CONTOUR, seed+52534, 4, 0.5,
			50, CAVE_NOISE_SCALE);
	//return NoiseParams(NOISE_CONSTANT_ONE);
}

NoiseParams get_cave_noise2_params(u64 seed)
{
	/*return NoiseParams(NOISE_PERLIN_CONTOUR_FLIP_YZ, seed+10325, 5, 0.7,
			200, CAVE_NOISE_SCALE);*/
	/*return NoiseParams(NOISE_PERLIN_CONTOUR_FLIP_YZ, seed+10325, 4, 0.7,
			100, CAVE_NOISE_SCALE);*/
	/*return NoiseParams(NOISE_PERLIN_CONTOUR_FLIP_YZ, seed+10325, 5, 0.3,
			100, CAVE_NOISE_SCALE);*/
	return NoiseParams(NOISE_PERLIN_CONTOUR_FLIP_YZ, seed+10325, 4, 0.5,
			50, CAVE_NOISE_SCALE);
	//return NoiseParams(NOISE_CONSTANT_ONE);
}

NoiseParams get_ground_noise1_params(u64 seed)
{
	return NoiseParams(NOISE_PERLIN, seed+983240, 4,
			0.55, 80.0, 40.0);
}

NoiseParams get_ground_crumbleness_params(u64 seed)
{
	return NoiseParams(NOISE_PERLIN, seed+34413, 3,
			1.3, 20.0, 1.0);
}

NoiseParams get_ground_wetness_params(u64 seed)
{
	return NoiseParams(NOISE_PERLIN, seed+32474, 4,
			1.1, 40.0, 1.0);
}

bool is_cave(u64 seed, v3s16 p)
{
	double d1 = noise3d_param(get_cave_noise1_params(seed), p.X,p.Y,p.Z);
	double d2 = noise3d_param(get_cave_noise2_params(seed), p.X,p.Y,p.Z);
	return d1*d2 > CAVE_NOISE_THRESHOLD;
}

/*
	Ground density noise shall be interpreted by using this.

	TODO: No perlin noises here, they should be outsourced
	      and buffered
		  NOTE: The speed of these actually isn't terrible
*/
bool val_is_ground(double ground_noise1_val, v3s16 p, u64 seed)
{
	//return ((double)p.Y < ground_noise1_val);

	double f = 0.55 + noise2d_perlin(
			0.5+(float)p.X/250, 0.5+(float)p.Z/250,
			seed+920381, 3, 0.45);
	if(f < 0.01)
		f = 0.01;
	else if(f >= 1.0)
		f *= 1.6;
	double h = WATER_LEVEL + 10 * noise2d_perlin(
			0.5+(float)p.X/250, 0.5+(float)p.Z/250,
			seed+84174, 4, 0.5);
	/*double f = 1;
	double h = 0;*/
	return ((double)p.Y - h < ground_noise1_val * f);
}

/*
	Queries whether a position is ground or not.
*/
bool is_ground(u64 seed, v3s16 p)
{
	double val1 = noise3d_param(get_ground_noise1_params(seed), p.X,p.Y,p.Z);
	return val_is_ground(val1, p, seed);
}

// Amount of trees per area in nodes
double tree_amount_2d(u64 seed, v2s16 p)
{
	/*double noise = noise2d_perlin(
			0.5+(float)p.X/250, 0.5+(float)p.Y/250,
			seed+2, 5, 0.66);*/
	double noise = noise2d_perlin(
			0.5+(float)p.X/125, 0.5+(float)p.Y/125,
			seed+2, 4, 0.66);
	double zeroval = -0.39;
	if(noise < zeroval)
		return 0;
	else
		return 0.04 * (noise-zeroval) / (1.0-zeroval);
}

double surface_humidity_2d(u64 seed, v2s16 p)
{
	double noise = noise2d_perlin(
			0.5+(float)p.X/500, 0.5+(float)p.Y/500,
			seed+72384, 4, 0.66);
	noise = (noise + 1.0)/2.0;
	if(noise < 0.0)
		noise = 0.0;
	if(noise > 1.0)
		noise = 1.0;
	return noise;
}

#if 0
double randomstone_amount_2d(u64 seed, v2s16 p)
{
	double noise = noise2d_perlin(
			0.5+(float)p.X/250, 0.5+(float)p.Y/250,
			seed+3829434, 5, 0.66);
	double zeroval = 0.1;
	if(noise < zeroval)
		return 0;
	else
		return 0.01 * (noise-zeroval) / (1.0-zeroval);
}
#endif

double largestone_amount_2d(u64 seed, v2s16 p)
{
	double noise = noise2d_perlin(
			0.5+(float)p.X/250, 0.5+(float)p.Y/250,
			seed+14143242, 5, 0.66);
	double zeroval = 0.3;
	if(noise < zeroval)
		return 0;
	else
		return 0.005 * (noise-zeroval) / (1.0-zeroval);
}

/*
	Incrementally find ground level from 3d noise
*/
s16 find_ground_level_from_noise(u64 seed, v2s16 p2d, s16 precision)
{
	// Start a bit fuzzy to make averaging lower precision values
	// more useful
	s16 level = myrand_range(-precision/2, precision/2);
	s16 dec[] = {31000, 100, 20, 4, 1, 0};
	s16 i;
	for(i = 1; dec[i] != 0 && precision <= dec[i]; i++)
	{
		// First find non-ground by going upwards
		// Don't stop in caves.
		{
			s16 max = level+dec[i-1]*2;
			v3s16 p(p2d.X, level, p2d.Y);
			for(; p.Y < max; p.Y += dec[i])
			{
				if(!is_ground(seed, p))
				{
					level = p.Y;
					break;
				}
			}
		}
		// Then find ground by going downwards from there.
		// Go in caves, too, when precision is 1.
		{
			s16 min = level-dec[i-1]*2;
			v3s16 p(p2d.X, level, p2d.Y);
			for(; p.Y>min; p.Y-=dec[i])
			{
				bool ground = is_ground(seed, p);
				/*if(dec[i] == 1 && is_cave(seed, p))
					ground = false;*/
				if(ground)
				{
					level = p.Y;
					break;
				}
			}
		}
	}
	
	// This is more like the actual ground level
	level += dec[i-1]/2;

	return level;
}

double get_sector_average_ground_level(u64 seed, v2s16 sectorpos, double p=4);

double get_sector_average_ground_level(u64 seed, v2s16 sectorpos, double p)
{
	v2s16 node_min = sectorpos*MAP_BLOCKSIZE;
	v2s16 node_max = (sectorpos+v2s16(1,1))*MAP_BLOCKSIZE-v2s16(1,1);
	double a = 0;
	a += find_ground_level_from_noise(seed,
			v2s16(node_min.X, node_min.Y), p);
	a += find_ground_level_from_noise(seed,
			v2s16(node_min.X, node_max.Y), p);
	a += find_ground_level_from_noise(seed,
			v2s16(node_max.X, node_max.Y), p);
	a += find_ground_level_from_noise(seed,
			v2s16(node_max.X, node_min.Y), p);
	a += find_ground_level_from_noise(seed,
			v2s16(node_min.X+MAP_BLOCKSIZE/2, node_min.Y+MAP_BLOCKSIZE/2), p);
	a /= 5;
	return a;
}

double get_sector_maximum_ground_level(u64 seed, v2s16 sectorpos, double p=4);

double get_sector_maximum_ground_level(u64 seed, v2s16 sectorpos, double p)
{
	v2s16 node_min = sectorpos*MAP_BLOCKSIZE;
	v2s16 node_max = (sectorpos+v2s16(1,1))*MAP_BLOCKSIZE-v2s16(1,1);
	double a = -31000;
	// Corners
	a = MYMAX(a, find_ground_level_from_noise(seed,
			v2s16(node_min.X, node_min.Y), p));
	a = MYMAX(a, find_ground_level_from_noise(seed,
			v2s16(node_min.X, node_max.Y), p));
	a = MYMAX(a, find_ground_level_from_noise(seed,
			v2s16(node_max.X, node_max.Y), p));
	a = MYMAX(a, find_ground_level_from_noise(seed,
			v2s16(node_min.X, node_min.Y), p));
	// Center
	a = MYMAX(a, find_ground_level_from_noise(seed,
			v2s16(node_min.X+MAP_BLOCKSIZE/2, node_min.Y+MAP_BLOCKSIZE/2), p));
	// Side middle points
	a = MYMAX(a, find_ground_level_from_noise(seed,
			v2s16(node_min.X+MAP_BLOCKSIZE/2, node_min.Y), p));
	a = MYMAX(a, find_ground_level_from_noise(seed,
			v2s16(node_min.X+MAP_BLOCKSIZE/2, node_max.Y), p));
	a = MYMAX(a, find_ground_level_from_noise(seed,
			v2s16(node_min.X, node_min.Y+MAP_BLOCKSIZE/2), p));
	a = MYMAX(a, find_ground_level_from_noise(seed,
			v2s16(node_max.X, node_min.Y+MAP_BLOCKSIZE/2), p));
	return a;
}

double get_sector_minimum_ground_level(u64 seed, v2s16 sectorpos, double p=4);

double get_sector_minimum_ground_level(u64 seed, v2s16 sectorpos, double p)
{
	v2s16 node_min = sectorpos*MAP_BLOCKSIZE;
	v2s16 node_max = (sectorpos+v2s16(1,1))*MAP_BLOCKSIZE-v2s16(1,1);
	double a = 31000;
	// Corners
	a = MYMIN(a, find_ground_level_from_noise(seed,
			v2s16(node_min.X, node_min.Y), p));
	a = MYMIN(a, find_ground_level_from_noise(seed,
			v2s16(node_min.X, node_max.Y), p));
	a = MYMIN(a, find_ground_level_from_noise(seed,
			v2s16(node_max.X, node_max.Y), p));
	a = MYMIN(a, find_ground_level_from_noise(seed,
			v2s16(node_min.X, node_min.Y), p));
	// Center
	a = MYMIN(a, find_ground_level_from_noise(seed,
			v2s16(node_min.X+MAP_BLOCKSIZE/2, node_min.Y+MAP_BLOCKSIZE/2), p));
	// Side middle points
	a = MYMIN(a, find_ground_level_from_noise(seed,
			v2s16(node_min.X+MAP_BLOCKSIZE/2, node_min.Y), p));
	a = MYMIN(a, find_ground_level_from_noise(seed,
			v2s16(node_min.X+MAP_BLOCKSIZE/2, node_max.Y), p));
	a = MYMIN(a, find_ground_level_from_noise(seed,
			v2s16(node_min.X, node_min.Y+MAP_BLOCKSIZE/2), p));
	a = MYMIN(a, find_ground_level_from_noise(seed,
			v2s16(node_max.X, node_min.Y+MAP_BLOCKSIZE/2), p));
	return a;
}

bool block_is_underground(u64 seed, v3s16 blockpos)
{
	s16 minimum_groundlevel = (s16)get_sector_minimum_ground_level(
			seed, v2s16(blockpos.X, blockpos.Z));
	
	if(blockpos.Y*MAP_BLOCKSIZE + MAP_BLOCKSIZE <= minimum_groundlevel)
		return true;
	else
		return false;
}

#if 0
#define AVERAGE_MUD_AMOUNT 4

double base_rock_level_2d(u64 seed, v2s16 p)
{
	// The base ground level
	double base = (double)WATER_LEVEL - (double)AVERAGE_MUD_AMOUNT
			+ 20. * noise2d_perlin(
			0.5+(float)p.X/500., 0.5+(float)p.Y/500.,
			(seed>>32)+654879876, 6, 0.6);

	/*// A bit hillier one
	double base2 = WATER_LEVEL - 4.0 + 40. * noise2d_perlin(
			0.5+(float)p.X/250., 0.5+(float)p.Y/250.,
			(seed>>27)+90340, 6, 0.69);
	if(base2 > base)
		base = base2;*/
#if 1
	// Higher ground level
	double higher = (double)WATER_LEVEL + 25. + 35. * noise2d_perlin(
			0.5+(float)p.X/250., 0.5+(float)p.Y/250.,
			seed+85039, 5, 0.69);
	//higher = 30; // For debugging

	// Limit higher to at least base
	if(higher < base)
		higher = base;

	// Steepness factor of cliffs
	double b = 1.0 + 1.0 * noise2d_perlin(
			0.5+(float)p.X/250., 0.5+(float)p.Y/250.,
			seed-932, 7, 0.7);
	b = rangelim(b, 0.0, 1000.0);
	b = pow(b, 5);
	b *= 7;
	b = rangelim(b, 3.0, 1000.0);
	//dstream<<"b="<<b<<std::endl;
	//double b = 20;

	// Offset to more low
	double a_off = -0.2;
	// High/low selector
	/*double a = 0.5 + b * (a_off + noise2d_perlin(
			0.5+(float)p.X/500., 0.5+(float)p.Y/500.,
			seed-359, 6, 0.7));*/
	double a = (double)0.5 + b * (a_off + noise2d_perlin(
			0.5+(float)p.X/250., 0.5+(float)p.Y/250.,
			seed-359, 5, 0.60));
	// Limit
	a = rangelim(a, 0.0, 1.0);

	//dstream<<"a="<<a<<std::endl;

	double h = base*(1.0-a) + higher*a;
#else
	double h = base;
#endif
	return h;
}

double get_mud_add_amount(u64 seed, v2s16 p)
{
	return ((float)AVERAGE_MUD_AMOUNT + 3.0 * noise2d_perlin(
			0.5+(float)p.X/200, 0.5+(float)p.Y/200,
			seed+91013, 3, 0.55));
}
#endif

bool get_have_sand(u64 seed, v2s16 p2d)
{
	// Determine whether to have sand here
	double sandnoise = noise2d_perlin(
			0.5+(float)p2d.X/500, 0.5+(float)p2d.Y/500,
			seed+59420, 3, 0.50);

	return (sandnoise > -0.15);
}

/*
	Adds random objects to block, depending on the content of the block
*/
void add_random_objects(MapBlock *block)
{
	for(s16 z0=0; z0<MAP_BLOCKSIZE; z0++)
	for(s16 x0=0; x0<MAP_BLOCKSIZE; x0++)
	{
		bool last_node_walkable = false;
		for(s16 y0=0; y0<MAP_BLOCKSIZE; y0++)
		{
			v3s16 p(x0,y0,z0);
			MapNode n = block->getNodeNoEx(p);
			if(n.getContent() == CONTENT_IGNORE)
				continue;
			if(content_features(n).liquid_type != LIQUID_NONE)
				continue;
			if(content_features(n).walkable)
			{
				last_node_walkable = true;
				continue;
			}
			if(last_node_walkable)
			{
				// If block contains light information
				if(content_features(n).param_type == CPT_LIGHT)
				{
					if(n.getLight(LIGHTBANK_DAY) <= 3)
					{
						if(myrand() % 300 == 0)
						{
							v3f pos_f = intToFloat(p+block->getPosRelative(), BS);
							pos_f.Y -= BS*0.4;
							ServerActiveObject *obj = new RatSAO(NULL, 0, pos_f);
							std::string data = obj->getStaticData();
							StaticObject s_obj(obj->getType(),
									obj->getBasePosition(), data);
							// Add some
							block->m_static_objects.insert(0, s_obj);
							block->m_static_objects.insert(0, s_obj);
							block->m_static_objects.insert(0, s_obj);
							block->m_static_objects.insert(0, s_obj);
							block->m_static_objects.insert(0, s_obj);
							block->m_static_objects.insert(0, s_obj);
							delete obj;
						}
						if(myrand() % 1000 == 0)
						{
							v3f pos_f = intToFloat(p+block->getPosRelative(), BS);
							pos_f.Y -= BS*0.4;
							ServerActiveObject *obj = new Oerkki1SAO(NULL,0,pos_f);
							std::string data = obj->getStaticData();
							StaticObject s_obj(obj->getType(),
									obj->getBasePosition(), data);
							// Add one
							block->m_static_objects.insert(0, s_obj);
							delete obj;
						}
					}
				}
			}
			last_node_walkable = false;
		}
	}
	block->setChangedFlag();
}

void make_block(BlockMakeData *data)
{
	if(data->no_op)
	{
		//dstream<<"makeBlock: no-op"<<std::endl;
		return;
	}

	v3s16 blockpos = data->blockpos;
	
	/*dstream<<"makeBlock(): ("<<blockpos.X<<","<<blockpos.Y<<","
			<<blockpos.Z<<")"<<std::endl;*/

	ManualMapVoxelManipulator &vmanip = *(data->vmanip);
	v3s16 blockpos_min = blockpos - v3s16(1,1,1);
	v3s16 blockpos_max = blockpos + v3s16(1,1,1);
	// Area of center block
	v3s16 node_min = blockpos*MAP_BLOCKSIZE;
	v3s16 node_max = (blockpos+v3s16(1,1,1))*MAP_BLOCKSIZE-v3s16(1,1,1);
	// Full allocated area
	v3s16 full_node_min = (blockpos-1)*MAP_BLOCKSIZE;
	v3s16 full_node_max = (blockpos+2)*MAP_BLOCKSIZE-v3s16(1,1,1);
	// Area of a block
	double block_area_nodes = MAP_BLOCKSIZE*MAP_BLOCKSIZE;

	v2s16 p2d_center(node_min.X+MAP_BLOCKSIZE/2, node_min.Z+MAP_BLOCKSIZE/2);

	/*
		Get average ground level from noise
	*/
	
	s16 approx_groundlevel = (s16)get_sector_average_ground_level(
			data->seed, v2s16(blockpos.X, blockpos.Z));
	//dstream<<"approx_groundlevel="<<approx_groundlevel<<std::endl;
	
	s16 approx_ground_depth = approx_groundlevel - (node_min.Y+MAP_BLOCKSIZE/2);
	
	s16 minimum_groundlevel = (s16)get_sector_minimum_ground_level(
			data->seed, v2s16(blockpos.X, blockpos.Z));
	// Minimum amount of ground above the top of the central block
	s16 minimum_ground_depth = minimum_groundlevel - node_max.Y;

	s16 maximum_groundlevel = (s16)get_sector_maximum_ground_level(
			data->seed, v2s16(blockpos.X, blockpos.Z), 1);
	// Maximum amount of ground above the bottom of the central block
	s16 maximum_ground_depth = maximum_groundlevel - node_min.Y;

	#if 0
	/*
		Special case for high air or water: Just fill with air and water.
	*/
	if(maximum_ground_depth < -20)
	{
		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(x,z);
			{
				// 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++)
				{
					// Only modify places that have no content
					if(vmanip.m_data[i].getContent() == CONTENT_IGNORE)
					{
						if(y <= WATER_LEVEL)
							vmanip.m_data[i] = MapNode(CONTENT_WATERSOURCE);
						else
							vmanip.m_data[i] = MapNode(CONTENT_AIR);
					}
				
					data->vmanip->m_area.add_y(em, i, 1);
				}
			}
		}
		
		// We're done
		return;
	}
	#endif

	/*
		If block is deep underground, this is set to true and ground
		density noise is not generated, for speed optimization.
	*/
	bool all_is_ground_except_caves = (minimum_ground_depth > 40);
	
	/*
		Create a block-specific seed
	*/
	u32 blockseed = (u32)(data->seed%0x100000000ULL) + full_node_min.Z*38134234
			+ full_node_min.Y*42123 + full_node_min.X*23;
	
	/*
		Make some 3D noise
	*/
	
	//NoiseBuffer noisebuf1;
	//NoiseBuffer noisebuf2;
	NoiseBuffer noisebuf_cave;
	NoiseBuffer noisebuf_ground;
	NoiseBuffer noisebuf_ground_crumbleness;
	NoiseBuffer noisebuf_ground_wetness;
	{
		v3f minpos_f(node_min.X, node_min.Y, node_min.Z);
		v3f maxpos_f(node_max.X, node_max.Y, node_max.Z);

		//TimeTaker timer("noisebuf.create");

		/*
			Cave noise
		*/
#if 1
		noisebuf_cave.create(get_cave_noise1_params(data->seed),
				minpos_f.X, minpos_f.Y, minpos_f.Z,
				maxpos_f.X, maxpos_f.Y, maxpos_f.Z,
				2, 2, 2);
		noisebuf_cave.multiply(get_cave_noise2_params(data->seed));
#endif

		/*
			Ground noise
		*/
		
		// Sample length
		v3f sl = v3f(4.0, 4.0, 4.0);
		
		/*
			Density noise
		*/
		if(all_is_ground_except_caves == false)
			//noisebuf_ground.create(data->seed+983240, 6, 0.60, false,
			noisebuf_ground.create(get_ground_noise1_params(data->seed),
					minpos_f.X, minpos_f.Y, minpos_f.Z,
					maxpos_f.X, maxpos_f.Y, maxpos_f.Z,
					sl.X, sl.Y, sl.Z);
		
		/*
			Ground property noise
		*/
		sl = v3f(2.5, 2.5, 2.5);
		noisebuf_ground_crumbleness.create(
				get_ground_crumbleness_params(data->seed),
				minpos_f.X, minpos_f.Y, minpos_f.Z,
				maxpos_f.X, maxpos_f.Y+5, maxpos_f.Z,
				sl.X, sl.Y, sl.Z);
		noisebuf_ground_wetness.create(
				get_ground_wetness_params(data->seed),
				minpos_f.X, minpos_f.Y, minpos_f.Z,
				maxpos_f.X, maxpos_f.Y+5, maxpos_f.Z,
				sl.X, sl.Y, sl.Z);
	}
	
	/*
		Make base 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(x,z);
		{
			// 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++)
			{
				// Only modify places that have no content
				if(vmanip.m_data[i].getContent() == CONTENT_IGNORE)
				{
					// First priority: make air and water.
					// This avoids caves inside water.
					if(all_is_ground_except_caves == false
							&& val_is_ground(noisebuf_ground.get(x,y,z),
							v3s16(x,y,z), data->seed) == false)
					{
						if(y <= WATER_LEVEL)
							vmanip.m_data[i] = MapNode(CONTENT_WATERSOURCE);
						else
							vmanip.m_data[i] = MapNode(CONTENT_AIR);
					}
					else if(noisebuf_cave.get(x,y,z) > CAVE_NOISE_THRESHOLD)
						vmanip.m_data[i] = MapNode(CONTENT_AIR);
					else
						vmanip.m_data[i] = MapNode(CONTENT_STONE);
				}
			
				data->vmanip->m_area.add_y(em, i, 1);
			}
		}
	}

	/*
		Add minerals
	*/

	{
		PseudoRandom mineralrandom(blockseed);

		/*
			Add meseblocks
		*/
		for(s16 i=0; i<approx_ground_depth/4; i++)
		{
			if(mineralrandom.next()%50 == 0)
			{
				s16 x = mineralrandom.range(node_min.X+1, node_max.X-1);
				s16 y = mineralrandom.range(node_min.Y+1, node_max.Y-1);
				s16 z = mineralrandom.range(node_min.Z+1, node_max.Z-1);
				for(u16 i=0; i<27; i++)
				{
					v3s16 p = v3s16(x,y,z) + g_27dirs[i];
					u32 vi = vmanip.m_area.index(p);
					if(vmanip.m_data[vi].getContent() == CONTENT_STONE)
						if(mineralrandom.next()%8 == 0)
							vmanip.m_data[vi] = MapNode(CONTENT_MESE);
				}
					
			}
		}
		/*
			Add others
		*/
		{
			u16 a = mineralrandom.range(0,15);
			a = a*a*a;
			u16 amount = 20 * a/1000;
			for(s16 i=0; i<amount; i++)
			{
				s16 x = mineralrandom.range(node_min.X+1, node_max.X-1);
				s16 y = mineralrandom.range(node_min.Y+1, node_max.Y-1);
				s16 z = mineralrandom.range(node_min.Z+1, node_max.Z-1);

				u8 base_content = CONTENT_STONE;
				MapNode new_content(CONTENT_IGNORE);
				u32 sparseness = 6;

				if(noisebuf_ground_crumbleness.get(x,y+5,z) < -0.1)
				{
					new_content = MapNode(CONTENT_STONE, MINERAL_COAL);
				}
				else
				{
					if(noisebuf_ground_wetness.get(x,y+5,z) > 0.0)
						new_content = MapNode(CONTENT_STONE, MINERAL_IRON);
					/*if(noisebuf_ground_wetness.get(x,y,z) > 0.0)
						vmanip.m_data[i] = MapNode(CONTENT_MUD);
					else
						vmanip.m_data[i] = MapNode(CONTENT_SAND);*/
				}
				/*else if(noisebuf_ground_crumbleness.get(x,y,z) > 0.1)
				{
				}*/

				if(new_content.getContent() != CONTENT_IGNORE)
				{
					for(u16 i=0; i<27; i++)
					{
						v3s16 p = v3s16(x,y,z) + g_27dirs[i];
						u32 vi = vmanip.m_area.index(p);
						if(vmanip.m_data[vi].getContent() == base_content)
						{
							if(mineralrandom.next()%sparseness == 0)
								vmanip.m_data[vi] = new_content;
						}
					}
				}
			}
		}
		/*
			Add coal
		*/
		//for(s16 i=0; i < MYMAX(0, 50 - abs(node_min.Y+8 - (-30))); i++)
		//for(s16 i=0; i<50; i++)
		u16 coal_amount = 30;
		u16 coal_rareness = 60 / coal_amount;
		if(coal_rareness == 0)
			coal_rareness = 1;
		if(mineralrandom.next()%coal_rareness == 0)
		{
			u16 a = mineralrandom.next() % 16;
			u16 amount = coal_amount * a*a*a / 1000;
			for(s16 i=0; i<amount; i++)
			{
				s16 x = mineralrandom.range(node_min.X+1, node_max.X-1);
				s16 y = mineralrandom.range(node_min.Y+1, node_max.Y-1);
				s16 z = mineralrandom.range(node_min.Z+1, node_max.Z-1);
				for(u16 i=0; i<27; i++)
				{
					v3s16 p = v3s16(x,y,z) + g_27dirs[i];
					u32 vi = vmanip.m_area.index(p);
					if(vmanip.m_data[vi].getContent() == CONTENT_STONE)
						if(mineralrandom.next()%8 == 0)
							vmanip.m_data[vi] = MapNode(CONTENT_STONE, MINERAL_COAL);
				}
			}
		}
		/*
			Add iron
		*/
		u16 iron_amount = 8;
		u16 iron_rareness = 60 / iron_amount;
		if(iron_rareness == 0)
			iron_rareness = 1;
		if(mineralrandom.next()%iron_rareness == 0)
		{
			u16 a = mineralrandom.next() % 16;
			u16 amount = iron_amount * a*a*a / 1000;
			for(s16 i=0; i<amount; i++)
			{
				s16 x = mineralrandom.range(node_min.X+1, node_max.X-1);
				s16 y = mineralrandom.range(node_min.Y+1, node_max.Y-1);
				s16 z = mineralrandom.range(node_min.Z+1, node_max.Z-1);
				for(u16 i=0; i<27; i++)
				{
					v3s16 p = v3s16(x,y,z) + g_27dirs[i];
					u32 vi = vmanip.m_area.index(p);
					if(vmanip.m_data[vi].getContent() == CONTENT_STONE)
						if(mineralrandom.next()%8 == 0)
							vmanip.m_data[vi] = MapNode(CONTENT_STONE, MINERAL_IRON);
				}
			}
		}
	}

	/*
		Add mud and sand and others underground (in place of stone)
	*/

	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(x,z);
		{
			// Use fast index incrementing
			v3s16 em = vmanip.m_area.getExtent();
			u32 i = vmanip.m_area.index(v3s16(p2d.X, node_max.Y, p2d.Y));
			for(s16 y=node_max.Y; y>=node_min.Y; y--)
			{
				if(vmanip.m_data[i].getContent() == CONTENT_STONE)
				{
					if(noisebuf_ground_crumbleness.get(x,y,z) > 1.3)
					{
						if(noisebuf_ground_wetness.get(x,y,z) > 0.0)
							vmanip.m_data[i] = MapNode(CONTENT_MUD);
						else
							vmanip.m_data[i] = MapNode(CONTENT_SAND);
					}
					else if(noisebuf_ground_crumbleness.get(x,y,z) > 0.7)
					{
						if(noisebuf_ground_wetness.get(x,y,z) < -0.6)
							vmanip.m_data[i] = MapNode(CONTENT_GRAVEL);
					}
				}

				data->vmanip->m_area.add_y(em, i, -1);
			}
		}
	}

	/*
		Add dungeons
	*/
	
	//if(node_min.Y < approx_groundlevel)
	//if(myrand() % 3 == 0)
	//if(myrand() % 3 == 0 && node_min.Y < approx_groundlevel)
	//if(myrand() % 100 == 0 && node_min.Y < approx_groundlevel)
	//float dungeon_rarity = g_settings.getFloat("dungeon_rarity");
	float dungeon_rarity = 0.02;
	if(((noise3d(blockpos.X,blockpos.Y,blockpos.Z,data->seed)+1.0)/2.0)
			< dungeon_rarity
			&& node_min.Y < approx_groundlevel)
	{
		// Dungeon generator doesn't modify places which have this set
		data->vmanip->clearFlag(VMANIP_FLAG_DUNGEON_INSIDE
				| VMANIP_FLAG_DUNGEON_PRESERVE);
		
		// Set all air and water to be untouchable to make dungeons open
		// to caves and open air
		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);
			{
				// 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(vmanip.m_data[i].getContent() == CONTENT_AIR)
						vmanip.m_flags[i] |= VMANIP_FLAG_DUNGEON_PRESERVE;
					else if(vmanip.m_data[i].getContent() == CONTENT_WATERSOURCE)
						vmanip.m_flags[i] |= VMANIP_FLAG_DUNGEON_PRESERVE;
					data->vmanip->m_area.add_y(em, i, -1);
				}
			}
		}
		
		PseudoRandom random(blockseed+2);

		// Add it
		make_dungeon1(vmanip, random);
		
		// Convert some cobble to mossy cobble
		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);
			{
				// 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--)
				{
					// (noisebuf not used because it doesn't contain the
					//  full area)
					double wetness = noise3d_param(
							get_ground_wetness_params(data->seed), x,y,z);
					double d = noise3d_perlin((float)x/2.5,
							(float)y/2.5,(float)z/2.5,
							blockseed, 2, 1.4);
					if(vmanip.m_data[i].getContent() == CONTENT_COBBLE)
					{
						if(d < wetness/3.0)
						{
							vmanip.m_data[i].setContent(CONTENT_MOSSYCOBBLE);
						}
					}
					/*else if(vmanip.m_flags[i] & VMANIP_FLAG_DUNGEON_INSIDE)
					{
						if(wetness > 1.2)
							vmanip.m_data[i].setContent(CONTENT_MUD);
					}*/
					data->vmanip->m_area.add_y(em, i, -1);
				}
			}
		}
	}

	/*
		Add NC
	*/
	{
		PseudoRandom ncrandom(blockseed+9324342);
		if(ncrandom.range(0, 1000) == 0 && blockpos.Y <= -3)
		{
			make_nc(vmanip, ncrandom);
		}
	}
	
	/*
		Add top and bottom side of water to transforming_liquid queue
	*/

	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(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, node_max.Y, p2d.Y));
			for(s16 y=node_max.Y; y>=node_min.Y; y--)
			{
				if(water_found == false)
				{
					if(vmanip.m_data[i].getContent() == CONTENT_WATERSOURCE)
					{
						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() != CONTENT_WATERSOURCE)
					{
						v3s16 p = v3s16(p2d.X, y+1, p2d.Y);
						data->transforming_liquid.push_back(p);
						water_found = false;
					}
				}

				data->vmanip->m_area.add_y(em, i, -1);
			}
		}
	}

	/*
		If close to ground level
	*/

	//if(abs(approx_ground_depth) < 30)
	if(minimum_ground_depth < 5 && maximum_ground_depth > -5)
	{
		/*
			Add grass and mud
		*/

		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(x,z);
			{
				bool possibly_have_sand = get_have_sand(data->seed, p2d);
				bool have_sand = false;
				u32 current_depth = 0;
				bool air_detected = false;
				bool water_detected = false;
				bool have_clay = false;

				// Use fast index incrementing
				s16 start_y = node_max.Y+2;
				v3s16 em = vmanip.m_area.getExtent();
				u32 i = vmanip.m_area.index(v3s16(p2d.X, start_y, p2d.Y));
				for(s16 y=start_y; y>=node_min.Y-3; y--)
				{
					if(vmanip.m_data[i].getContent() == CONTENT_WATERSOURCE)
						water_detected = true;
					if(vmanip.m_data[i].getContent() == CONTENT_AIR)
						air_detected = true;

					if((vmanip.m_data[i].getContent() == CONTENT_STONE
							|| vmanip.m_data[i].getContent() == CONTENT_GRASS
							|| vmanip.m_data[i].getContent() == CONTENT_MUD
							|| vmanip.m_data[i].getContent() == CONTENT_SAND
							|| vmanip.m_data[i].getContent() == CONTENT_GRAVEL
							) && (air_detected || water_detected))
					{
						if(current_depth == 0 && y <= WATER_LEVEL+2
								&& possibly_have_sand)
							have_sand = true;
						
						if(current_depth < 4)
						{
							if(have_sand)
							{
								// Determine whether to have clay in the sand here
								double claynoise = noise2d_perlin(
										0.5+(float)p2d.X/500, 0.5+(float)p2d.Y/500,
										data->seed+4321, 6, 0.95) + 0.5;
				
								have_clay = (y <= WATER_LEVEL) && (y >= WATER_LEVEL-2) && (
									((claynoise > 0) && (claynoise < 0.04) && (current_depth == 0)) ||
									((claynoise > 0) && (claynoise < 0.12) && (current_depth == 1))
									);
								if (have_clay)
									vmanip.m_data[i] = MapNode(CONTENT_CLAY);
								else
									vmanip.m_data[i] = MapNode(CONTENT_SAND);
							}
							#if 1
							else if(current_depth==0 && !water_detected
									&& y >= WATER_LEVEL && air_detected)
								vmanip.m_data[i] = MapNode(CONTENT_GRASS);
							#endif
							else
								vmanip.m_data[i] = MapNode(CONTENT_MUD);
						}
						else
						{
							if(vmanip.m_data[i].getContent() == CONTENT_MUD
								|| vmanip.m_data[i].getContent() == CONTENT_GRASS)
								vmanip.m_data[i] = MapNode(CONTENT_STONE);
						}

						current_depth++;

						if(current_depth >= 8)
							break;
					}
					else if(current_depth != 0)
						break;

					data->vmanip->m_area.add_y(em, i, -1);
				}
			}
		}

		/*
			Calculate some stuff
		*/
		
		float surface_humidity = surface_humidity_2d(data->seed, p2d_center);
		bool is_jungle = surface_humidity > 0.75;
		// Amount of trees
		u32 tree_count = block_area_nodes * tree_amount_2d(data->seed, p2d_center);
		if(is_jungle)
			tree_count *= 5;

		/*
			Add trees
		*/
		PseudoRandom treerandom(blockseed);
		// Put trees in random places on part of division
		for(u32 i=0; i<tree_count; i++)
		{
			s16 x = treerandom.range(node_min.X, node_max.X);
			s16 z = treerandom.range(node_min.Z, node_max.Z);
			//s16 y = find_ground_level(data->vmanip, v2s16(x,z));
			s16 y = find_ground_level_from_noise(data->seed, v2s16(x,z), 4);
			// Don't make a tree under water level
			if(y < WATER_LEVEL)
				continue;
			// Make sure tree fits (only trees whose starting point is
			// at this block are added)
			if(y < node_min.Y || y > node_max.Y)
				continue;
			/*
				Find exact ground level
			*/
			v3s16 p(x,y+6,z);
			bool found = false;
			for(; p.Y >= y-6; p.Y--)
			{
				u32 i = data->vmanip->m_area.index(p);
				MapNode *n = &data->vmanip->m_data[i];
				if(n->getContent() != CONTENT_AIR && n->getContent() != CONTENT_WATERSOURCE && n->getContent() != CONTENT_IGNORE)
				{
					found = true;
					break;
				}
			}
			// If not found, handle next one
			if(found == false)
				continue;

			{
				u32 i = data->vmanip->m_area.index(p);
				MapNode *n = &data->vmanip->m_data[i];

				if(n->getContent() != CONTENT_MUD && n->getContent() != CONTENT_GRASS && n->getContent() != CONTENT_SAND)
						continue;

				// Papyrus grows only on mud and in water
				if(n->getContent() == CONTENT_MUD && y <= WATER_LEVEL)
				{
					p.Y++;
					make_papyrus(vmanip, p);
				}
				// Trees grow only on mud and grass, on land
				else if((n->getContent() == CONTENT_MUD || n->getContent() == CONTENT_GRASS) && y > WATER_LEVEL + 2)
				{
					p.Y++;
					//if(surface_humidity_2d(data->seed, v2s16(x, y)) < 0.5)
					if(is_jungle == false)
						make_tree(vmanip, p);
					else
						make_jungletree(vmanip, p);
				}
				// Cactii grow only on sand, on land
				else if(n->getContent() == CONTENT_SAND && y > WATER_LEVEL + 2)
				{
					p.Y++;
					make_cactus(vmanip, p);
				}
			}
		}

		/*
			Add jungle grass
		*/
		if(is_jungle)
		{
			PseudoRandom grassrandom(blockseed);
			for(u32 i=0; i<surface_humidity*5*tree_count; i++)
			{
				s16 x = grassrandom.range(node_min.X, node_max.X);
				s16 z = grassrandom.range(node_min.Z, node_max.Z);
				s16 y = find_ground_level_from_noise(data->seed, v2s16(x,z), 4);
				if(y < WATER_LEVEL)
					continue;
				if(y < node_min.Y || y > node_max.Y)
					continue;
				/*
					Find exact ground level
				*/
				v3s16 p(x,y+6,z);
				bool found = false;
				for(; p.Y >= y-6; p.Y--)
				{
					u32 i = data->vmanip->m_area.index(p);
					MapNode *n = &data->vmanip->m_data[i];
					if(content_features(*n).is_ground_content
							|| n->getContent() == CONTENT_JUNGLETREE)
					{
						found = true;
						break;
					}
				}
				// If not found, handle next one
				if(found == false)
					continue;
				p.Y++;
				if(vmanip.m_area.contains(p) == false)
					continue;
				if(vmanip.m_data[vmanip.m_area.index(p)].getContent() != CONTENT_AIR)
					continue;
				/*p.Y--;
				if(vmanip.m_area.contains(p))
					vmanip.m_data[vmanip.m_area.index(p)] = CONTENT_MUD;
				p.Y++;*/
				if(vmanip.m_area.contains(p))
					vmanip.m_data[vmanip.m_area.index(p)] = CONTENT_JUNGLEGRASS;
			}
		}

#if 0
		/*
			Add some kind of random stones
		*/
		
		u32 random_stone_count = block_area_nodes *
				randomstone_amount_2d(data->seed, p2d_center);
		// Put in random places on part of division
		for(u32 i=0; i<random_stone_count; i++)
		{
			s16 x = myrand_range(node_min.X, node_max.X);
			s16 z = myrand_range(node_min.Z, node_max.Z);
			s16 y = find_ground_level_from_noise(data->seed, v2s16(x,z), 1);
			// Don't add under water level
			/*if(y < WATER_LEVEL)
				continue;*/
			// Don't add if doesn't belong to this block
			if(y < node_min.Y || y > node_max.Y)
				continue;
			v3s16 p(x,y,z);
			// Filter placement
			/*{
				u32 i = data->vmanip->m_area.index(v3s16(p));
				MapNode *n = &data->vmanip->m_data[i];
				if(n->getContent() != CONTENT_MUD && n->getContent() != CONTENT_GRASS)
					continue;
			}*/
			// Will be placed one higher
			p.Y++;
			// Add it
			make_randomstone(data->vmanip, p);
		}
#endif

#if 0
		/*
			Add larger stones
		*/
		
		u32 large_stone_count = block_area_nodes *
				largestone_amount_2d(data->seed, p2d_center);
		//u32 large_stone_count = 1;
		// Put in random places on part of division
		for(u32 i=0; i<large_stone_count; i++)
		{
			s16 x = myrand_range(node_min.X, node_max.X);
			s16 z = myrand_range(node_min.Z, node_max.Z);
			s16 y = find_ground_level_from_noise(data->seed, v2s16(x,z), 1);
			// Don't add under water level
			/*if(y < WATER_LEVEL)
				continue;*/
			// Don't add if doesn't belong to this block
			if(y < node_min.Y || y > node_max.Y)
				continue;
			v3s16 p(x,y,z);
			// Filter placement
			/*{
				u32 i = data->vmanip->m_area.index(v3s16(p));
				MapNode *n = &data->vmanip->m_data[i];
				if(n->getContent() != CONTENT_MUD && n->getContent() != CONTENT_GRASS)
					continue;
			}*/
			// Will be placed one lower
			p.Y--;
			// Add it
			make_largestone(data->vmanip, p);
		}
#endif
	}

}

BlockMakeData::BlockMakeData():
	no_op(false),
	vmanip(NULL),
	seed(0)
{}

BlockMakeData::~BlockMakeData()
{
	delete vmanip;
}

}; // namespace mapgen