mapblock_mesh.cpp

/*
Minetest
Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/

#include "mapblock_mesh.h"
#include "light.h"
#include "mapblock.h"
#include "map.h"
#include "main.h" // for g_profiler
#include "profiler.h"
#include "nodedef.h"
#include "gamedef.h"
#include "mesh.h"
#include "content_mapblock.h"
#include "noise.h"
#include "shader.h"
#include "settings.h"
#include "util/directiontables.h"

void applyContrast(video::SColor& color, float Factor)
{
	float r = color.getRed();
	float g = color.getGreen();
	float b = color.getBlue();
	color.setRed(irr::core::clamp((int)sqrt(r * r * Factor), 0, 255));
	color.setGreen(irr::core::clamp((int)sqrt(g * g * Factor), 0, 255));
	color.setBlue(irr::core::clamp((int)sqrt(b * b * Factor), 0, 255));
}

/*
	MeshMakeData
*/

MeshMakeData::MeshMakeData(IGameDef *gamedef):
	m_vmanip(),
	m_blockpos(-1337,-1337,-1337),
	m_crack_pos_relative(-1337, -1337, -1337),
	m_smooth_lighting(false),
	m_gamedef(gamedef)
{}

void MeshMakeData::fill(MapBlock *block)
{
	m_blockpos = block->getPos();

	v3s16 blockpos_nodes = m_blockpos*MAP_BLOCKSIZE;

	/*
		Copy data
	*/

	// Allocate this block + neighbors
	m_vmanip.clear();
	m_vmanip.addArea(VoxelArea(blockpos_nodes-v3s16(1,1,1)*MAP_BLOCKSIZE,
			blockpos_nodes+v3s16(1,1,1)*MAP_BLOCKSIZE*2-v3s16(1,1,1)));

	{
		//TimeTaker timer("copy central block data");
		// 0ms

		// Copy our data
		block->copyTo(m_vmanip);
	}
	{
		//TimeTaker timer("copy neighbor block data");
		// 0ms

		/*
			Copy neighbors. This is lightning fast.
			Copying only the borders would be *very* slow.
		*/

		// Get map
		Map *map = block->getParent();

		for(u16 i=0; i<26; i++)
		{
			const v3s16 &dir = g_26dirs[i];
			v3s16 bp = m_blockpos + dir;
			MapBlock *b = map->getBlockNoCreateNoEx(bp);
			if(b)
				b->copyTo(m_vmanip);
		}
	}
}

void MeshMakeData::fillSingleNode(MapNode *node)
{
	m_blockpos = v3s16(0,0,0);

	v3s16 blockpos_nodes = v3s16(0,0,0);
	VoxelArea area(blockpos_nodes-v3s16(1,1,1)*MAP_BLOCKSIZE,
			blockpos_nodes+v3s16(1,1,1)*MAP_BLOCKSIZE*2-v3s16(1,1,1));
	s32 volume = area.getVolume();
	s32 our_node_index = area.index(1,1,1);

	// Allocate this block + neighbors
	m_vmanip.clear();
	m_vmanip.addArea(area);

	// Fill in data
	MapNode *data = new MapNode[volume];
	for(s32 i = 0; i < volume; i++)
	{
		if(i == our_node_index)
		{
			data[i] = *node;
		}
		else
		{
			data[i] = MapNode(CONTENT_AIR, LIGHT_MAX, 0);
		}
	}
	m_vmanip.copyFrom(data, area, area.MinEdge, area.MinEdge, area.getExtent());
	delete[] data;
}

void MeshMakeData::setCrack(int crack_level, v3s16 crack_pos)
{
	if(crack_level >= 0)
		m_crack_pos_relative = crack_pos - m_blockpos*MAP_BLOCKSIZE;
}

void MeshMakeData::setSmoothLighting(bool smooth_lighting)
{
	m_smooth_lighting = smooth_lighting;
}

/*
	Light and vertex color functions
*/

/*
	Calculate non-smooth lighting at interior of node.
	Single light bank.
*/
static u8 getInteriorLight(enum LightBank bank, MapNode n, s32 increment,
		INodeDefManager *ndef)
{
	u8 light = n.getLight(bank, ndef);

	while(increment > 0)
	{
		light = undiminish_light(light);
		--increment;
	}
	while(increment < 0)
	{
		light = diminish_light(light);
		++increment;
	}

	return decode_light(light);
}

/*
	Calculate non-smooth lighting at interior of node.
	Both light banks.
*/
u16 getInteriorLight(MapNode n, s32 increment, INodeDefManager *ndef)
{
	u16 day = getInteriorLight(LIGHTBANK_DAY, n, increment, ndef);
	u16 night = getInteriorLight(LIGHTBANK_NIGHT, n, increment, ndef);
	return day | (night << 8);
}

/*
	Calculate non-smooth lighting at face of node.
	Single light bank.
*/
static u8 getFaceLight(enum LightBank bank, MapNode n, MapNode n2,
		v3s16 face_dir, INodeDefManager *ndef)
{
	u8 light;
	u8 l1 = n.getLight(bank, ndef);
	u8 l2 = n2.getLight(bank, ndef);
	if(l1 > l2)
		light = l1;
	else
		light = l2;

	// Boost light level for light sources
	u8 light_source = MYMAX(ndef->get(n).light_source,
			ndef->get(n2).light_source);
	//if(light_source >= light)
		//return decode_light(undiminish_light(light_source));
	if(light_source > light)
		//return decode_light(light_source);
		light = light_source;

	return decode_light(light);
}

/*
	Calculate non-smooth lighting at face of node.
	Both light banks.
*/
u16 getFaceLight(MapNode n, MapNode n2, v3s16 face_dir, INodeDefManager *ndef)
{
	u16 day = getFaceLight(LIGHTBANK_DAY, n, n2, face_dir, ndef);
	u16 night = getFaceLight(LIGHTBANK_NIGHT, n, n2, face_dir, ndef);
	return day | (night << 8);
}

/*
	Calculate smooth lighting at the XYZ- corner of p.
	Single light bank.
*/
static u8 getSmoothLight(enum LightBank bank, v3s16 p, MeshMakeData *data)
{
	static v3s16 dirs8[8] = {
		v3s16(0,0,0),
		v3s16(0,0,1),
		v3s16(0,1,0),
		v3s16(0,1,1),
		v3s16(1,0,0),
		v3s16(1,1,0),
		v3s16(1,0,1),
		v3s16(1,1,1),
	};

	INodeDefManager *ndef = data->m_gamedef->ndef();

	u16 ambient_occlusion = 0;
	u16 light = 0;
	u16 light_count = 0;
	u8 light_source_max = 0;
	for(u32 i=0; i<8; i++)
	{
		MapNode n = data->m_vmanip.getNodeNoEx(p - dirs8[i]);

		// if it's CONTENT_IGNORE we can't do any light calculations
		if (n.getContent() == CONTENT_IGNORE) {
			continue;
		}

		const ContentFeatures &f = ndef->get(n);
		if(f.light_source > light_source_max)
			light_source_max = f.light_source;
		// Check f.solidness because fast-style leaves look
		// better this way
		if(f.param_type == CPT_LIGHT && f.solidness != 2)
		{
			light += decode_light(n.getLight(bank, ndef));
			light_count++;
		}
		else {
			ambient_occlusion++;
		}
	}

	if(light_count == 0)
		return 255;

	light /= light_count;

	// Boost brightness around light sources
	if(decode_light(light_source_max) >= light)
		//return decode_light(undiminish_light(light_source_max));
		return decode_light(light_source_max);

	if(ambient_occlusion > 4)
	{
		//ambient_occlusion -= 4;
		//light = (float)light / ((float)ambient_occlusion * 0.5 + 1.0);
		float light_amount = (8 - ambient_occlusion) / 4.0;
		float light_f = (float)light / 255.0;
		light_f = pow(light_f, 2.2f); // gamma -> linear space
		light_f = light_f * light_amount;
		light_f = pow(light_f, 1.0f/2.2f); // linear -> gamma space
		if(light_f > 1.0)
			light_f = 1.0;
		light = 255.0 * light_f + 0.5;
	}

	return light;
}

/*
	Calculate smooth lighting at the XYZ- corner of p.
	Both light banks.
*/
static u16 getSmoothLight(v3s16 p, MeshMakeData *data)
{
	u16 day = getSmoothLight(LIGHTBANK_DAY, p, data);
	u16 night = getSmoothLight(LIGHTBANK_NIGHT, p, data);
	return day | (night << 8);
}

/*
	Calculate smooth lighting at the given corner of p.
	Both light banks.
*/
u16 getSmoothLight(v3s16 p, v3s16 corner, MeshMakeData *data)
{
	if(corner.X == 1) p.X += 1;
	else              assert(corner.X == -1);
	if(corner.Y == 1) p.Y += 1;
	else              assert(corner.Y == -1);
	if(corner.Z == 1) p.Z += 1;
	else              assert(corner.Z == -1);

	return getSmoothLight(p, data);
}

/*
	Converts from day + night color values (0..255)
	and a given daynight_ratio to the final SColor shown on screen.
*/
static void finalColorBlend(video::SColor& result,
		u8 day, u8 night, u32 daynight_ratio)
{
	s32 rg = (day * daynight_ratio + night * (1000-daynight_ratio)) / 1000;
	s32 b = rg;

	// Moonlight is blue
	b += (day - night) / 13;
	rg -= (day - night) / 23;

	// Emphase blue a bit in darker places
	// Each entry of this array represents a range of 8 blue levels
	static u8 emphase_blue_when_dark[32] = {
		1, 4, 6, 6, 6, 5, 4, 3, 2, 1, 0, 0, 0, 0, 0, 0,
		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	};
	b += emphase_blue_when_dark[b / 8];
	b = irr::core::clamp (b, 0, 255);

	// Artificial light is yellow-ish
	static u8 emphase_yellow_when_artificial[16] = {
		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 10, 15, 15, 15
	};
	rg += emphase_yellow_when_artificial[night/16];
	rg = irr::core::clamp (rg, 0, 255);

	result.setRed(rg);
	result.setGreen(rg);
	result.setBlue(b);
}

/*
	Mesh generation helpers
*/

/*
	vertex_dirs: v3s16[4]
*/
static void getNodeVertexDirs(v3s16 dir, v3s16 *vertex_dirs)
{
	/*
		If looked from outside the node towards the face, the corners are:
		0: bottom-right
		1: bottom-left
		2: top-left
		3: top-right
	*/
	if(dir == v3s16(0,0,1))
	{
		// If looking towards z+, this is the face that is behind
		// the center point, facing towards z+.
		vertex_dirs[0] = v3s16(-1,-1, 1);
		vertex_dirs[1] = v3s16( 1,-1, 1);
		vertex_dirs[2] = v3s16( 1, 1, 1);
		vertex_dirs[3] = v3s16(-1, 1, 1);
	}
	else if(dir == v3s16(0,0,-1))
	{
		// faces towards Z-
		vertex_dirs[0] = v3s16( 1,-1,-1);
		vertex_dirs[1] = v3s16(-1,-1,-1);
		vertex_dirs[2] = v3s16(-1, 1,-1);
		vertex_dirs[3] = v3s16( 1, 1,-1);
	}
	else if(dir == v3s16(1,0,0))
	{
		// faces towards X+
		vertex_dirs[0] = v3s16( 1,-1, 1);
		vertex_dirs[1] = v3s16( 1,-1,-1);
		vertex_dirs[2] = v3s16( 1, 1,-1);
		vertex_dirs[3] = v3s16( 1, 1, 1);
	}
	else if(dir == v3s16(-1,0,0))
	{
		// faces towards X-
		vertex_dirs[0] = v3s16(-1,-1,-1);
		vertex_dirs[1] = v3s16(-1,-1, 1);
		vertex_dirs[2] = v3s16(-1, 1, 1);
		vertex_dirs[3] = v3s16(-1, 1,-1);
	}
	else if(dir == v3s16(0,1,0))
	{
		// faces towards Y+ (assume Z- as "down" in texture)
		vertex_dirs[0] = v3s16( 1, 1,-1);
		vertex_dirs[1] = v3s16(-1, 1,-1);
		vertex_dirs[2] = v3s16(-1, 1, 1);
		vertex_dirs[3] = v3s16( 1, 1, 1);
	}
	else if(dir == v3s16(0,-1,0))
	{
		// faces towards Y- (assume Z+ as "down" in texture)
		vertex_dirs[0] = v3s16( 1,-1, 1);
		vertex_dirs[1] = v3s16(-1,-1, 1);
		vertex_dirs[2] = v3s16(-1,-1,-1);
		vertex_dirs[3] = v3s16( 1,-1,-1);
	}
}

struct FastFace
{
	TileSpec tile;
	video::S3DVertex vertices[4]; // Precalculated vertices
};

static void makeFastFace(TileSpec tile, u16 li0, u16 li1, u16 li2, u16 li3,
		v3f p, v3s16 dir, v3f scale, u8 light_source, std::vector<FastFace> &dest)
{
	FastFace face;

	// Position is at the center of the cube.
	v3f pos = p * BS;

	float x0 = 0.0;
	float y0 = 0.0;
	float w = 1.0;
	float h = 1.0;

	v3f vertex_pos[4];
	v3s16 vertex_dirs[4];
	getNodeVertexDirs(dir, vertex_dirs);

	v3s16 t;
	u16 t1;
	switch (tile.rotation)
	{
	case 0:
		break;
	case 1: //R90
		t = vertex_dirs[0];
		vertex_dirs[0] = vertex_dirs[3];
		vertex_dirs[3] = vertex_dirs[2];
		vertex_dirs[2] = vertex_dirs[1];
		vertex_dirs[1] = t;
		t1=li0;
		li0=li3;
		li3=li2;
		li2=li1;
		li1=t1;
		break;
	case 2: //R180
		t = vertex_dirs[0];
		vertex_dirs[0] = vertex_dirs[2];
		vertex_dirs[2] = t;
		t = vertex_dirs[1];
		vertex_dirs[1] = vertex_dirs[3];
		vertex_dirs[3] = t;
		t1  = li0;
		li0 = li2;
		li2 = t1;
		t1  = li1;
		li1 = li3;
		li3 = t1;
		break;
	case 3: //R270
		t = vertex_dirs[0];
		vertex_dirs[0] = vertex_dirs[1];
		vertex_dirs[1] = vertex_dirs[2];
		vertex_dirs[2] = vertex_dirs[3];
		vertex_dirs[3] = t;
		t1  = li0;
		li0 = li1;
		li1 = li2;
		li2 = li3;
		li3 = t1;
		break;
	case 4: //FXR90
		t = vertex_dirs[0];
		vertex_dirs[0] = vertex_dirs[3];
		vertex_dirs[3] = vertex_dirs[2];
		vertex_dirs[2] = vertex_dirs[1];
		vertex_dirs[1] = t;
		t1  = li0;
		li0 = li3;
		li3 = li2;
		li2 = li1;
		li1 = t1;
		y0 += h;
		h *= -1;
		break;
	case 5: //FXR270
		t = vertex_dirs[0];
		vertex_dirs[0] = vertex_dirs[1];
		vertex_dirs[1] = vertex_dirs[2];
		vertex_dirs[2] = vertex_dirs[3];
		vertex_dirs[3] = t;
		t1  = li0;
		li0 = li1;
		li1 = li2;
		li2 = li3;
		li3 = t1;
		y0 += h;
		h *= -1;
		break;
	case 6: //FYR90
		t = vertex_dirs[0];
		vertex_dirs[0] = vertex_dirs[3];
		vertex_dirs[3] = vertex_dirs[2];
		vertex_dirs[2] = vertex_dirs[1];
		vertex_dirs[1] = t;
		t1  = li0;
		li0 = li3;
		li3 = li2;
		li2 = li1;
		li1 = t1;
		x0 += w;
		w *= -1;
		break;
	case 7: //FYR270
		t = vertex_dirs[0];
		vertex_dirs[0] = vertex_dirs[1];
		vertex_dirs[1] = vertex_dirs[2];
		vertex_dirs[2] = vertex_dirs[3];
		vertex_dirs[3] = t;
		t1  = li0;
		li0 = li1;
		li1 = li2;
		li2 = li3;
		li3 = t1;
		x0 += w;
		w *= -1;
		break;
	case 8: //FX
		y0 += h;
		h *= -1;
		break;
	case 9: //FY
		x0 += w;
		w *= -1;
		break;
	default:
		break;
	}

	for(u16 i=0; i<4; i++)
	{
		vertex_pos[i] = v3f(
				BS/2*vertex_dirs[i].X,
				BS/2*vertex_dirs[i].Y,
				BS/2*vertex_dirs[i].Z
		);
	}

	for(u16 i=0; i<4; i++)
	{
		vertex_pos[i].X *= scale.X;
		vertex_pos[i].Y *= scale.Y;
		vertex_pos[i].Z *= scale.Z;
		vertex_pos[i] += pos;
	}

	f32 abs_scale = 1.0;
	if     (scale.X < 0.999 || scale.X > 1.001) abs_scale = scale.X;
	else if(scale.Y < 0.999 || scale.Y > 1.001) abs_scale = scale.Y;
	else if(scale.Z < 0.999 || scale.Z > 1.001) abs_scale = scale.Z;

	v3f normal(dir.X, dir.Y, dir.Z);

	u8 alpha = tile.alpha;

	face.vertices[0] = video::S3DVertex(vertex_pos[0], normal,
			MapBlock_LightColor(alpha, li0, light_source),
			core::vector2d<f32>(x0+w*abs_scale, y0+h));
	face.vertices[1] = video::S3DVertex(vertex_pos[1], normal,
			MapBlock_LightColor(alpha, li1, light_source),
			core::vector2d<f32>(x0, y0+h));
	face.vertices[2] = video::S3DVertex(vertex_pos[2], normal,
			MapBlock_LightColor(alpha, li2, light_source),
			core::vector2d<f32>(x0, y0));
	face.vertices[3] = video::S3DVertex(vertex_pos[3], normal,
			MapBlock_LightColor(alpha, li3, light_source),
			core::vector2d<f32>(x0+w*abs_scale, y0));

	face.tile = tile;
	dest.push_back(face);
}

/*
	Nodes make a face if contents differ and solidness differs.
	Return value:
		0: No face
		1: Face uses m1's content
		2: Face uses m2's content
	equivalent: Whether the blocks share the same face (eg. water and glass)

	TODO: Add 3: Both faces drawn with backface culling, remove equivalent
*/
static u8 face_contents(content_t m1, content_t m2, bool *equivalent,
		INodeDefManager *ndef)
{
	*equivalent = false;

	if(m1 == CONTENT_IGNORE || m2 == CONTENT_IGNORE)
		return 0;

	bool contents_differ = (m1 != m2);

	const ContentFeatures &f1 = ndef->get(m1);
	const ContentFeatures &f2 = ndef->get(m2);

	// Contents don't differ for different forms of same liquid
	if(f1.sameLiquid(f2))
		contents_differ = false;

	u8 c1 = f1.solidness;
	u8 c2 = f2.solidness;

	bool solidness_differs = (c1 != c2);
	bool makes_face = contents_differ && solidness_differs;

	if(makes_face == false)
		return 0;

	if(c1 == 0)
		c1 = f1.visual_solidness;
	if(c2 == 0)
		c2 = f2.visual_solidness;

	if(c1 == c2){
		*equivalent = true;
		// If same solidness, liquid takes precense
		if(f1.isLiquid())
			return 1;
		if(f2.isLiquid())
			return 2;
	}

	if(c1 > c2)
		return 1;
	else
		return 2;
}

/*
	Gets nth node tile (0 <= n <= 5).
*/
TileSpec getNodeTileN(MapNode mn, v3s16 p, u8 tileindex, MeshMakeData *data)
{
	INodeDefManager *ndef = data->m_gamedef->ndef();
	TileSpec spec = ndef->get(mn).tiles[tileindex];
	// Apply temporary crack
	if(p == data->m_crack_pos_relative)
	{
		spec.material_flags |= MATERIAL_FLAG_CRACK;
	}
	return spec;
}

/*
	Gets node tile given a face direction.
*/
TileSpec getNodeTile(MapNode mn, v3s16 p, v3s16 dir, MeshMakeData *data)
{
	INodeDefManager *ndef = data->m_gamedef->ndef();

	// Direction must be (1,0,0), (-1,0,0), (0,1,0), (0,-1,0),
	// (0,0,1), (0,0,-1) or (0,0,0)
	assert(dir.X * dir.X + dir.Y * dir.Y + dir.Z * dir.Z <= 1);

	// Convert direction to single integer for table lookup
	//  0 = (0,0,0)
	//  1 = (1,0,0)
	//  2 = (0,1,0)
	//  3 = (0,0,1)
	//  4 = invalid, treat as (0,0,0)
	//  5 = (0,0,-1)
	//  6 = (0,-1,0)
	//  7 = (-1,0,0)
	u8 dir_i = ((dir.X + 2 * dir.Y + 3 * dir.Z) & 7)*2;

	// Get rotation for things like chests
	u8 facedir = mn.getFaceDir(ndef);
	if (facedir > 23)
		facedir = 0;
	static const u16 dir_to_tile[24 * 16] =
	{
		// 0     +X    +Y    +Z           -Z    -Y    -X   ->   value=tile,rotation
		   0,0,  2,0 , 0,0 , 4,0 ,  0,0,  5,0 , 1,0 , 3,0 ,  // rotate around y+ 0 - 3
		   0,0,  4,0 , 0,3 , 3,0 ,  0,0,  2,0 , 1,1 , 5,0 ,
		   0,0,  3,0 , 0,2 , 5,0 ,  0,0,  4,0 , 1,2 , 2,0 ,
		   0,0,  5,0 , 0,1 , 2,0 ,  0,0,  3,0 , 1,3 , 4,0 ,

		   0,0,  2,3 , 5,0 , 0,2 ,  0,0,  1,0 , 4,2 , 3,1 ,  // rotate around z+ 4 - 7
		   0,0,  4,3 , 2,0 , 0,1 ,  0,0,  1,1 , 3,2 , 5,1 ,
		   0,0,  3,3 , 4,0 , 0,0 ,  0,0,  1,2 , 5,2 , 2,1 ,
		   0,0,  5,3 , 3,0 , 0,3 ,  0,0,  1,3 , 2,2 , 4,1 ,

		   0,0,  2,1 , 4,2 , 1,2 ,  0,0,  0,0 , 5,0 , 3,3 ,  // rotate around z- 8 - 11
		   0,0,  4,1 , 3,2 , 1,3 ,  0,0,  0,3 , 2,0 , 5,3 ,
		   0,0,  3,1 , 5,2 , 1,0 ,  0,0,  0,2 , 4,0 , 2,3 ,
		   0,0,  5,1 , 2,2 , 1,1 ,  0,0,  0,1 , 3,0 , 4,3 ,

		   0,0,  0,3 , 3,3 , 4,1 ,  0,0,  5,3 , 2,3 , 1,3 ,  // rotate around x+ 12 - 15
		   0,0,  0,2 , 5,3 , 3,1 ,  0,0,  2,3 , 4,3 , 1,0 ,
		   0,0,  0,1 , 2,3 , 5,1 ,  0,0,  4,3 , 3,3 , 1,1 ,
		   0,0,  0,0 , 4,3 , 2,1 ,  0,0,  3,3 , 5,3 , 1,2 ,

		   0,0,  1,1 , 2,1 , 4,3 ,  0,0,  5,1 , 3,1 , 0,1 ,  // rotate around x- 16 - 19
		   0,0,  1,2 , 4,1 , 3,3 ,  0,0,  2,1 , 5,1 , 0,0 ,
		   0,0,  1,3 , 3,1 , 5,3 ,  0,0,  4,1 , 2,1 , 0,3 ,
		   0,0,  1,0 , 5,1 , 2,3 ,  0,0,  3,1 , 4,1 , 0,2 ,

		   0,0,  3,2 , 1,2 , 4,2 ,  0,0,  5,2 , 0,2 , 2,2 ,  // rotate around y- 20 - 23
		   0,0,  5,2 , 1,3 , 3,2 ,  0,0,  2,2 , 0,1 , 4,2 ,
		   0,0,  2,2 , 1,0 , 5,2 ,  0,0,  4,2 , 0,0 , 3,2 ,
		   0,0,  4,2 , 1,1 , 2,2 ,  0,0,  3,2 , 0,3 , 5,2

	};
	u16 tile_index=facedir*16 + dir_i;
	TileSpec spec = getNodeTileN(mn, p, dir_to_tile[tile_index], data);
	spec.rotation=dir_to_tile[tile_index + 1];
	spec.texture = data->m_gamedef->tsrc()->getTexture(spec.texture_id);
	return spec;
}

static void getTileInfo(
		// Input:
		MeshMakeData *data,
		v3s16 p,
		v3s16 face_dir,
		// Output:
		bool &makes_face,
		v3s16 &p_corrected,
		v3s16 &face_dir_corrected,
		u16 *lights,
		TileSpec &tile,
		u8 &light_source
	)
{
	VoxelManipulator &vmanip = data->m_vmanip;
	INodeDefManager *ndef = data->m_gamedef->ndef();
	v3s16 blockpos_nodes = data->m_blockpos * MAP_BLOCKSIZE;

	MapNode n0 = vmanip.getNodeNoEx(blockpos_nodes + p);

	// Don't even try to get n1 if n0 is already CONTENT_IGNORE
	if (n0.getContent() == CONTENT_IGNORE ) {
		makes_face = false;
		return;
	}
	MapNode n1 = vmanip.getNodeNoEx(blockpos_nodes + p + face_dir);

	// This is hackish
	bool equivalent = false;
	u8 mf = face_contents(n0.getContent(), n1.getContent(),
			&equivalent, ndef);

	if(mf == 0)
	{
		makes_face = false;
		return;
	}

	makes_face = true;

	if(mf == 1)
	{
		tile = getNodeTile(n0, p, face_dir, data);
		p_corrected = p;
		face_dir_corrected = face_dir;
		light_source = ndef->get(n0).light_source;
	}
	else
	{
		tile = getNodeTile(n1, p + face_dir, -face_dir, data);
		p_corrected = p + face_dir;
		face_dir_corrected = -face_dir;
		light_source = ndef->get(n1).light_source;
	}

	// eg. water and glass
	if(equivalent)
		tile.material_flags |= MATERIAL_FLAG_BACKFACE_CULLING;

	if(data->m_smooth_lighting == false)
	{
		lights[0] = lights[1] = lights[2] = lights[3] =
				getFaceLight(n0, n1, face_dir, ndef);
	}
	else
	{
		v3s16 vertex_dirs[4];
		getNodeVertexDirs(face_dir_corrected, vertex_dirs);
		for(u16 i=0; i<4; i++)
		{
			lights[i] = getSmoothLight(
					blockpos_nodes + p_corrected,
					vertex_dirs[i], data);
		}
	}

	return;
}

/*
	startpos:
	translate_dir: unit vector with only one of x, y or z
	face_dir: unit vector with only one of x, y or z
*/
static void updateFastFaceRow(
		MeshMakeData *data,
		v3s16 startpos,
		v3s16 translate_dir,
		v3f translate_dir_f,
		v3s16 face_dir,
		v3f face_dir_f,
		std::vector<FastFace> &dest)
{
	v3s16 p = startpos;

	u16 continuous_tiles_count = 0;

	bool makes_face = false;
	v3s16 p_corrected;
	v3s16 face_dir_corrected;
	u16 lights[4] = {0,0,0,0};
	TileSpec tile;
	u8 light_source = 0;
	getTileInfo(data, p, face_dir,
			makes_face, p_corrected, face_dir_corrected,
			lights, tile, light_source);

	for(u16 j=0; j<MAP_BLOCKSIZE; j++)
	{
		// If tiling can be done, this is set to false in the next step
		bool next_is_different = true;

		v3s16 p_next;

		bool next_makes_face = false;
		v3s16 next_p_corrected;
		v3s16 next_face_dir_corrected;
		u16 next_lights[4] = {0,0,0,0};
		TileSpec next_tile;
		u8 next_light_source = 0;

		// If at last position, there is nothing to compare to and
		// the face must be drawn anyway
		if(j != MAP_BLOCKSIZE - 1)
		{
			p_next = p + translate_dir;

			getTileInfo(data, p_next, face_dir,
					next_makes_face, next_p_corrected,
					next_face_dir_corrected, next_lights,
					next_tile, next_light_source);

			if(next_makes_face == makes_face
					&& next_p_corrected == p_corrected + translate_dir
					&& next_face_dir_corrected == face_dir_corrected
					&& next_lights[0] == lights[0]
					&& next_lights[1] == lights[1]
					&& next_lights[2] == lights[2]
					&& next_lights[3] == lights[3]
					&& next_tile == tile
					&& tile.rotation == 0
					&& next_light_source == light_source)
			{
				next_is_different = false;
			}
			else{
				/*if(makes_face){
					g_profiler->add("Meshgen: diff: next_makes_face != makes_face",
							next_makes_face != makes_face ? 1 : 0);
					g_profiler->add("Meshgen: diff: n_p_corr != p_corr + t_dir",
							(next_p_corrected != p_corrected + translate_dir) ? 1 : 0);
					g_profiler->add("Meshgen: diff: next_f_dir_corr != f_dir_corr",
							next_face_dir_corrected != face_dir_corrected ? 1 : 0);
					g_profiler->add("Meshgen: diff: next_lights[] != lights[]",
							(next_lights[0] != lights[0] ||
							next_lights[0] != lights[0] ||
							next_lights[0] != lights[0] ||
							next_lights[0] != lights[0]) ? 1 : 0);
					g_profiler->add("Meshgen: diff: !(next_tile == tile)",
							!(next_tile == tile) ? 1 : 0);
				}*/
			}
			/*g_profiler->add("Meshgen: Total faces checked", 1);
			if(makes_face)
				g_profiler->add("Meshgen: Total makes_face checked", 1);*/
		} else {
			/*if(makes_face)
				g_profiler->add("Meshgen: diff: last position", 1);*/
		}

		continuous_tiles_count++;

		if(next_is_different)
		{
			/*
				Create a face if there should be one
			*/
			if(makes_face)
			{
				// Floating point conversion of the position vector
				v3f pf(p_corrected.X, p_corrected.Y, p_corrected.Z);
				// Center point of face (kind of)
				v3f sp = pf - ((f32)continuous_tiles_count / 2. - 0.5) * translate_dir_f;
				if(continuous_tiles_count != 1)
					sp += translate_dir_f;
				v3f scale(1,1,1);

				if(translate_dir.X != 0)
				{
					scale.X = continuous_tiles_count;
				}
				if(translate_dir.Y != 0)
				{
					scale.Y = continuous_tiles_count;
				}
				if(translate_dir.Z != 0)
				{
					scale.Z = continuous_tiles_count;
				}

				makeFastFace(tile, lights[0], lights[1], lights[2], lights[3],
						sp, face_dir_corrected, scale, light_source,
						dest);

				g_profiler->avg("Meshgen: faces drawn by tiling", 0);
				for(int i=1; i<continuous_tiles_count; i++){
					g_profiler->avg("Meshgen: faces drawn by tiling", 1);
				}
			}

			continuous_tiles_count = 0;

			makes_face = next_makes_face;
			p_corrected = next_p_corrected;
			face_dir_corrected = next_face_dir_corrected;
			lights[0] = next_lights[0];
			lights[1] = next_lights[1];
			lights[2] = next_lights[2];
			lights[3] = next_lights[3];
			tile = next_tile;
			light_source = next_light_source;
		}

		p = p_next;
	}
}

static void updateAllFastFaceRows(MeshMakeData *data,
		std::vector<FastFace> &dest)
{
	/*
		Go through every y,z and get top(y+) faces in rows of x+
	*/
	for(s16 y=0; y<MAP_BLOCKSIZE; y++){
		for(s16 z=0; z<MAP_BLOCKSIZE; z++){
			updateFastFaceRow(data,
					v3s16(0,y,z),
					v3s16(1,0,0), //dir
					v3f  (1,0,0),
					v3s16(0,1,0), //face dir
					v3f  (0,1,0),
					dest);
		}
	}

	/*
		Go through every x,y and get right(x+) faces in rows of z+
	*/
	for(s16 x=0; x<MAP_BLOCKSIZE; x++){
		for(s16 y=0; y<MAP_BLOCKSIZE; y++){
			updateFastFaceRow(data,
					v3s16(x,y,0),
					v3s16(0,0,1), //dir
					v3f  (0,0,1),
					v3s16(1,0,0), //face dir
					v3f  (1,0,0),
					dest);
		}
	}

	/*
		Go through every y,z and get back(z+) faces in rows of x+