Moved source to src

src/Generating/BioGen.cpp

@@ -0,0 +1,707 @@
+
+// BioGen.cpp
+
+// Implements the various biome generators
+
+#include "Globals.h"
+#include "BioGen.h"
+#include "../../iniFile/iniFile.h"
+#include "../LinearUpscale.h"
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cBioGenConstant:
+
+void cBioGenConstant::GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap)
+{
+	for (int i = 0; i < ARRAYCOUNT(a_BiomeMap); i++)
+	{
+		a_BiomeMap[i] = m_Biome;
+	}
+}
+
+
+
+
+
+void cBioGenConstant::InitializeBiomeGen(cIniFile & a_IniFile)
+{
+	AString Biome = a_IniFile.GetValueSet("Generator", "ConstantBiome", "Plains");
+	m_Biome = StringToBiome(Biome);
+	if (m_Biome == -1)
+	{
+		LOGWARN("[Generator]::ConstantBiome value \"%s\" not recognized, using \"Plains\".", Biome.c_str());
+		m_Biome = biPlains;
+	}
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cBioGenCache:
+
+cBioGenCache::cBioGenCache(cBiomeGen * a_BioGenToCache, int a_CacheSize) :
+	m_BioGenToCache(a_BioGenToCache),
+	m_CacheSize(a_CacheSize),
+	m_CacheOrder(new int[a_CacheSize]),
+	m_CacheData(new sCacheData[a_CacheSize]),
+	m_NumHits(0),
+	m_NumMisses(0),
+	m_TotalChain(0)
+{
+	for (int i = 0; i < m_CacheSize; i++)
+	{
+		m_CacheOrder[i] = i;
+		m_CacheData[i].m_ChunkX = 0x7fffffff;
+		m_CacheData[i].m_ChunkZ = 0x7fffffff;
+	}
+}
+
+
+
+
+
+cBioGenCache::~cBioGenCache()
+{
+	delete[] m_CacheData;
+	delete[] m_CacheOrder;
+}
+
+
+
+
+
+void cBioGenCache::GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap)
+{
+	if (((m_NumHits + m_NumMisses) % 1024) == 10)
+	{
+		LOGD("BioGenCache: %d hits, %d misses, saved %.2f %%", m_NumHits, m_NumMisses, 100.0 * m_NumHits / (m_NumHits + m_NumMisses));
+		LOGD("BioGenCache: Avg cache chain length: %.2f", (float)m_TotalChain / m_NumHits);
+	}
+	
+	for (int i = 0; i < m_CacheSize; i++)
+	{
+		if (
+			(m_CacheData[m_CacheOrder[i]].m_ChunkX != a_ChunkX) ||
+			(m_CacheData[m_CacheOrder[i]].m_ChunkZ != a_ChunkZ)
+		)
+		{
+			continue;
+		}
+		// Found it in the cache
+		int Idx = m_CacheOrder[i];
+		
+		// Move to front:
+		for (int j = i; j > 0; j--)
+		{
+			m_CacheOrder[j] = m_CacheOrder[j - 1];
+		}
+		m_CacheOrder[0] = Idx;
+		
+		// Use the cached data:
+		memcpy(a_BiomeMap, m_CacheData[Idx].m_BiomeMap, sizeof(a_BiomeMap));
+		
+		m_NumHits++;
+		m_TotalChain += i;
+		return;
+	}  // for i - cache
+	
+	// Not in the cache:
+	m_NumMisses++;
+	m_BioGenToCache->GenBiomes(a_ChunkX, a_ChunkZ, a_BiomeMap);
+	
+	// Insert it as the first item in the MRU order:
+	int Idx = m_CacheOrder[m_CacheSize - 1];
+	for (int i = m_CacheSize - 1; i > 0; i--)
+	{
+		m_CacheOrder[i] = m_CacheOrder[i - 1];
+	}  // for i - m_CacheOrder[]
+	m_CacheOrder[0] = Idx;
+	memcpy(m_CacheData[Idx].m_BiomeMap, a_BiomeMap, sizeof(a_BiomeMap));
+	m_CacheData[Idx].m_ChunkX = a_ChunkX;
+	m_CacheData[Idx].m_ChunkZ = a_ChunkZ;
+}
+
+
+
+
+
+void cBioGenCache::InitializeBiomeGen(cIniFile & a_IniFile)
+{
+	super::InitializeBiomeGen(a_IniFile);
+	m_BioGenToCache->InitializeBiomeGen(a_IniFile);
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cBiomeGenList:
+
+void cBiomeGenList::InitializeBiomes(const AString & a_Biomes)
+{
+	AStringVector Split = StringSplit(a_Biomes, ",");
+
+	// Convert each string in the list into biome:
+	for (AStringVector::const_iterator itr = Split.begin(); itr != Split.end(); ++itr)
+	{
+		AStringVector Split2 = StringSplit(*itr, ":");
+		if (Split2.size() < 1)
+		{
+			continue;
+		}
+		int Count = 1;
+		if (Split2.size() >= 2)
+		{
+			Count = atol(Split2[1].c_str());
+			if (Count <= 0)
+			{
+				LOGWARNING("Cannot decode biome count: \"%s\"; using 1.", Split2[1].c_str());
+				Count = 1;
+			}
+		}
+		EMCSBiome Biome = StringToBiome(Split2[0]);
+		if (Biome != -1)
+		{
+			for (int i = 0; i < Count; i++)
+			{
+				m_Biomes.push_back(Biome);
+			}
+		}
+		else
+		{
+			LOGWARNING("Cannot decode biome name: \"%s\"; skipping", Split2[0].c_str());
+		}
+	}  // for itr - Split[]
+	if (!m_Biomes.empty())
+	{
+		m_BiomesCount = (int)m_Biomes.size();
+		return;
+	}
+
+	// There were no biomes, add default biomes:
+	static EMCSBiome Biomes[] =
+	{
+		biOcean,
+		biPlains,
+		biDesert,
+		biExtremeHills,
+		biForest,
+		biTaiga,
+		biSwampland,
+		biRiver,
+		biFrozenOcean,
+		biFrozenRiver,
+		biIcePlains,
+		biIceMountains,
+		biMushroomIsland,
+		biMushroomShore,
+		biBeach,
+		biDesertHills,
+		biForestHills,
+		biTaigaHills,
+		biExtremeHillsEdge,
+		biJungle,
+		biJungleHills,
+	} ;
+	m_Biomes.reserve(ARRAYCOUNT(Biomes));
+	for (int i = 0; i < ARRAYCOUNT(Biomes); i++)
+	{
+		m_Biomes.push_back(Biomes[i]);
+	}
+	m_BiomesCount = (int)m_Biomes.size();
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cBioGenCheckerboard:
+
+void cBioGenCheckerboard::GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap)
+{
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		int Base = cChunkDef::Width * a_ChunkZ + z;
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			int Add = cChunkDef::Width * a_ChunkX + x;
+			a_BiomeMap[x + cChunkDef::Width * z] = m_Biomes[(Base / m_BiomeSize + Add / m_BiomeSize) % m_BiomesCount];
+		}
+	}
+}
+
+
+
+
+
+void cBioGenCheckerboard::InitializeBiomeGen(cIniFile & a_IniFile)
+{
+	super::InitializeBiomeGen(a_IniFile);
+	AString Biomes = a_IniFile.GetValueSet ("Generator", "CheckerBoardBiomes",    "");
+	m_BiomeSize    = a_IniFile.GetValueSetI("Generator", "CheckerboardBiomeSize", 64);
+	m_BiomeSize = (m_BiomeSize < 8) ? 8 : m_BiomeSize;
+	InitializeBiomes(Biomes);
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cBioGenVoronoi :
+
+void cBioGenVoronoi::GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap)
+{
+	int BaseZ = cChunkDef::Width * a_ChunkZ;
+	int BaseX = cChunkDef::Width * a_ChunkX;
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		int AbsoluteZ = BaseZ + z;
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			cChunkDef::SetBiome(a_BiomeMap, x, z, VoronoiBiome(BaseX + x, AbsoluteZ));
+		}  // for x
+	}  // for z
+}
+
+
+
+
+
+void cBioGenVoronoi::InitializeBiomeGen(cIniFile & a_IniFile)
+{
+	super::InitializeBiomeGen(a_IniFile);
+	m_CellSize     = a_IniFile.GetValueSetI("Generator", "VoronoiCellSize", 64);
+	AString Biomes = a_IniFile.GetValueSet ("Generator", "VoronoiBiomes",   "");
+	InitializeBiomes(Biomes);
+}
+
+
+
+
+
+EMCSBiome cBioGenVoronoi::VoronoiBiome(int a_BlockX, int a_BlockZ)
+{
+	int CellX = a_BlockX / m_CellSize;
+	int CellZ = a_BlockZ / m_CellSize;
+	
+	// Note that Noise values need to be divided by 8 to gain a uniform modulo-2^n distribution
+	
+	// Get 5x5 neighboring cell seeds, compare distance to each. Return the biome in the minumim-distance cell
+	int MinDist = m_CellSize * m_CellSize * 16;  // There has to be a cell closer than this
+	EMCSBiome res = biPlains;  // Will be overriden
+	for (int x = CellX - 2; x <= CellX + 2; x++)
+	{
+		int BaseX = x * m_CellSize;
+		for (int z = CellZ - 2; z < CellZ + 2; z++)
+		{
+			int OffsetX = (m_Noise.IntNoise3DInt(x, 16 * x + 32 * z, z) / 8) % m_CellSize;
+			int OffsetZ = (m_Noise.IntNoise3DInt(x, 32 * x - 16 * z, z) / 8) % m_CellSize;
+			int SeedX = BaseX + OffsetX;
+			int SeedZ = z * m_CellSize + OffsetZ;
+			
+			int Dist = (SeedX - a_BlockX) * (SeedX - a_BlockX) + (SeedZ - a_BlockZ) * (SeedZ - a_BlockZ);
+			if (Dist < MinDist)
+			{
+				MinDist = Dist;
+				res = m_Biomes[(m_Noise.IntNoise3DInt(x, x - z + 1000, z) / 8) % m_BiomesCount];
+			}
+		}  // for z
+	}  // for x
+
+	return res;
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cBioGenDistortedVoronoi:
+
+void cBioGenDistortedVoronoi::GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap)
+{
+	int BaseZ = cChunkDef::Width * a_ChunkZ;
+	int BaseX = cChunkDef::Width * a_ChunkX;
+	
+	// Distortions for linear interpolation:
+	int DistortX[cChunkDef::Width + 1][cChunkDef::Width + 1];
+	int DistortZ[cChunkDef::Width + 1][cChunkDef::Width + 1];
+	for (int x = 0; x <= 4; x++) for (int z = 0; z <= 4; z++)
+	{
+		Distort(BaseX + x * 4, BaseZ + z * 4, DistortX[4 * x][4 * z], DistortZ[4 * x][4 * z]);
+	}
+	
+	LinearUpscale2DArrayInPlace(&DistortX[0][0], cChunkDef::Width + 1, cChunkDef::Width + 1, 4, 4);
+	LinearUpscale2DArrayInPlace(&DistortZ[0][0], cChunkDef::Width + 1, cChunkDef::Width + 1, 4, 4);
+	
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		int AbsoluteZ = BaseZ + z;
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			// Distort(BaseX + x, AbsoluteZ, DistX, DistZ);
+			cChunkDef::SetBiome(a_BiomeMap, x, z, VoronoiBiome(DistortX[x][z], DistortZ[x][z]));
+		}  // for x
+	}  // for z
+}
+
+
+
+
+
+void cBioGenDistortedVoronoi::InitializeBiomeGen(cIniFile & a_IniFile)
+{
+	// Do NOT call super::InitializeBiomeGen(), as it would try to read Voronoi params instead of DistortedVoronoi params
+	m_CellSize     = a_IniFile.GetValueSetI("Generator", "DistortedVoronoiCellSize", 96);
+	AString Biomes = a_IniFile.GetValueSet ("Generator", "DistortedVoronoiBiomes",   "");
+	InitializeBiomes(Biomes);
+}
+
+
+
+
+void cBioGenDistortedVoronoi::Distort(int a_BlockX, int a_BlockZ, int & a_DistortedX, int & a_DistortedZ)
+{
+	double NoiseX = m_Noise.CubicNoise3D((float)a_BlockX / m_CellSize, (float)a_BlockZ / m_CellSize, 1000);
+	NoiseX += 0.5 * m_Noise.CubicNoise3D(2 *  (float)a_BlockX / m_CellSize, 2 *  (float)a_BlockZ / m_CellSize, 2000);
+	NoiseX += 0.08 * m_Noise.CubicNoise3D(16 * (float)a_BlockX / m_CellSize, 16 * (float)a_BlockZ / m_CellSize, 3000);
+	double NoiseZ = m_Noise.CubicNoise3D((float)a_BlockX / m_CellSize, (float)a_BlockZ / m_CellSize, 4000);
+	NoiseZ += 0.5 * m_Noise.CubicNoise3D(2 *  (float)a_BlockX / m_CellSize, 2 *  (float)a_BlockZ / m_CellSize, 5000);
+	NoiseZ += 0.08 * m_Noise.CubicNoise3D(16 * (float)a_BlockX / m_CellSize, 16 * (float)a_BlockZ / m_CellSize, 6000);
+	
+	a_DistortedX = a_BlockX + (int)(m_CellSize * 0.5 * NoiseX);
+	a_DistortedZ = a_BlockZ + (int)(m_CellSize * 0.5 * NoiseZ);
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cBioGenMultiStepMap :
+
+cBioGenMultiStepMap::cBioGenMultiStepMap(int a_Seed) :
+	m_Noise1(a_Seed + 1000),
+	m_Noise2(a_Seed + 2000),
+	m_Noise3(a_Seed + 3000),
+	m_Noise4(a_Seed + 4000),
+	m_Noise5(a_Seed + 5000),
+	m_Noise6(a_Seed + 6000),
+	m_Seed(a_Seed),
+	m_OceanCellSize(384),
+	m_MushroomIslandSize(64),
+	m_RiverCellSize(384),
+	m_RiverWidthThreshold(0.125),
+	m_LandBiomesSize(1024)
+{
+}
+
+
+
+
+
+void cBioGenMultiStepMap::InitializeBiomeGen(cIniFile & a_IniFile)
+{
+	m_OceanCellSize       =        a_IniFile.GetValueSetI("Generator", "MultiStepMapOceanCellSize",      m_OceanCellSize);
+	m_MushroomIslandSize  =        a_IniFile.GetValueSetI("Generator", "MultiStepMapMushroomIslandSize", m_MushroomIslandSize);
+	m_RiverCellSize       =        a_IniFile.GetValueSetI("Generator", "MultiStepMapRiverCellSize",      m_RiverCellSize);
+	m_RiverWidthThreshold =        a_IniFile.GetValueSetF("Generator", "MultiStepMapRiverWidth",         m_RiverWidthThreshold);
+	m_LandBiomesSize      = (float)a_IniFile.GetValueSetI("Generator", "MultiStepMapLandBiomeSize",      (int)m_LandBiomesSize);
+}
+
+
+
+
+
+void cBioGenMultiStepMap::GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap)
+{
+	DecideOceanLandMushroom(a_ChunkX, a_ChunkZ, a_BiomeMap);
+	AddRivers(a_ChunkX, a_ChunkZ, a_BiomeMap);
+	ApplyTemperatureHumidity(a_ChunkX, a_ChunkZ, a_BiomeMap);
+}
+
+
+
+
+
+void cBioGenMultiStepMap::DecideOceanLandMushroom(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap)
+{
+	// Distorted Voronoi over 3 biomes, with mushroom having only a special occurence.
+	
+	// Prepare a distortion lookup table, by distorting a 5x5 area and using that as 1:4 zoom (linear interpolate):
+	int BaseZ = cChunkDef::Width * a_ChunkZ;
+	int BaseX = cChunkDef::Width * a_ChunkX;
+	int DistortX[cChunkDef::Width + 1][cChunkDef::Width + 1];
+	int DistortZ[cChunkDef::Width + 1][cChunkDef::Width + 1];
+	int DistortSize = m_OceanCellSize / 2;
+	for (int x = 0; x <= 4; x++) for (int z = 0; z <= 4; z++)
+	{
+		Distort(BaseX + x * 4, BaseZ + z * 4, DistortX[4 * x][4 * z], DistortZ[4 * x][4 * z], DistortSize);
+	}
+	LinearUpscale2DArrayInPlace(&DistortX[0][0], cChunkDef::Width + 1, cChunkDef::Width + 1, 4, 4);
+	LinearUpscale2DArrayInPlace(&DistortZ[0][0], cChunkDef::Width + 1, cChunkDef::Width + 1, 4, 4);
+	
+	// Prepare a 9x9 area of neighboring cell seeds
+	// (assuming that 7x7 cell area is larger than a chunk being generated)
+	const int NEIGHBORHOOD_SIZE = 4;  // How many seeds in each direction to check
+	int CellX = BaseX / m_OceanCellSize;
+	int CellZ = BaseZ / m_OceanCellSize;
+	int SeedX[2 * NEIGHBORHOOD_SIZE + 1][2 * NEIGHBORHOOD_SIZE + 1];
+	int SeedZ[2 * NEIGHBORHOOD_SIZE + 1][2 * NEIGHBORHOOD_SIZE + 1];
+	EMCSBiome SeedV[2 * NEIGHBORHOOD_SIZE + 1][2 * NEIGHBORHOOD_SIZE + 1];
+	for (int xc = 0; xc < 2 * NEIGHBORHOOD_SIZE + 1; xc++)
+	{
+		int RealCellX = xc + CellX - NEIGHBORHOOD_SIZE;
+		int CellBlockX = RealCellX * m_OceanCellSize;
+		for (int zc = 0; zc < 2 * NEIGHBORHOOD_SIZE + 1; zc++)
+		{
+			int RealCellZ = zc + CellZ - NEIGHBORHOOD_SIZE;
+			int CellBlockZ = RealCellZ * m_OceanCellSize;
+			int OffsetX = (m_Noise2.IntNoise3DInt(RealCellX, 16 * RealCellX + 32 * RealCellZ, RealCellZ) / 8) % m_OceanCellSize;
+			int OffsetZ = (m_Noise4.IntNoise3DInt(RealCellX, 32 * RealCellX - 16 * RealCellZ, RealCellZ) / 8) % m_OceanCellSize;
+			SeedX[xc][zc] = CellBlockX + OffsetX;
+			SeedZ[xc][zc] = CellBlockZ + OffsetZ;
+			SeedV[xc][zc] = (((m_Noise6.IntNoise3DInt(RealCellX, RealCellX - RealCellZ + 1000, RealCellZ) / 11) % 256) > 90) ? biOcean : ((EMCSBiome)(-1));
+		}  // for z
+	}  // for x
+	
+	for (int xc = 1; xc < 2 * NEIGHBORHOOD_SIZE; xc++) for (int zc = 1; zc < 2 * NEIGHBORHOOD_SIZE; zc++)
+	{
+		if (
+			(SeedV[xc    ][zc]     == biOcean) &&
+			(SeedV[xc - 1][zc]     == biOcean) &&
+			(SeedV[xc + 1][zc]     == biOcean) &&
+			(SeedV[xc    ][zc - 1] == biOcean) &&
+			(SeedV[xc    ][zc + 1] == biOcean) &&
+			(SeedV[xc - 1][zc - 1] == biOcean) &&
+			(SeedV[xc + 1][zc - 1] == biOcean) &&
+			(SeedV[xc - 1][zc + 1] == biOcean) &&
+			(SeedV[xc + 1][zc + 1] == biOcean)
+		)
+		{
+			SeedV[xc][zc] = biMushroomIsland;
+		}
+	}
+	
+	// For each column find the nearest distorted cell and use its value as the biome:
+	int MushroomOceanThreshold = m_OceanCellSize * m_OceanCellSize * m_MushroomIslandSize / 1024;
+	int MushroomShoreThreshold = m_OceanCellSize * m_OceanCellSize * m_MushroomIslandSize / 2048;
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			int AbsoluteZ = DistortZ[x][z];
+			int AbsoluteX = DistortX[x][z];
+			int MinDist = m_OceanCellSize * m_OceanCellSize * 16;  // There has to be a cell closer than this
+			EMCSBiome Biome = biPlains;
+			// Find the nearest cell seed:
+			for (int xs = 1; xs < 2 * NEIGHBORHOOD_SIZE; xs++) for (int zs = 1; zs < 2 * NEIGHBORHOOD_SIZE; zs++)
+			{
+				int Dist = (SeedX[xs][zs] - AbsoluteX) * (SeedX[xs][zs] - AbsoluteX) + (SeedZ[xs][zs] - AbsoluteZ) * (SeedZ[xs][zs] - AbsoluteZ);
+				if (Dist >= MinDist)
+				{
+					continue;
+				}
+				MinDist = Dist;
+				Biome = SeedV[xs][zs];
+				// Shrink mushroom biome and add a shore:
+				if (Biome == biMushroomIsland)
+				{
+					if (Dist > MushroomOceanThreshold)
+					{
+						Biome = biOcean;
+					}
+					else if (Dist > MushroomShoreThreshold)
+					{
+						Biome = biMushroomShore;
+					}
+				}
+			}  // for zs, xs
+
+			cChunkDef::SetBiome(a_BiomeMap, x, z, Biome);
+		}  // for x
+	}  // for z
+}
+
+
+
+
+
+void cBioGenMultiStepMap::AddRivers(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap)
+{
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		float NoiseCoordZ = (float)(a_ChunkZ * cChunkDef::Width + z) / m_RiverCellSize;
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			if (cChunkDef::GetBiome(a_BiomeMap, x, z) != -1)
+			{
+				// Biome already set, skip this column
+				continue;
+			}
+			
+			float NoiseCoordX = (float)(a_ChunkX * cChunkDef::Width + x) / m_RiverCellSize;
+		
+			double Noise = m_Noise1.CubicNoise2D(    NoiseCoordX,     NoiseCoordZ);
+			Noise += 0.5 * m_Noise3.CubicNoise2D(2 * NoiseCoordX, 2 * NoiseCoordZ);
+			Noise += 0.1 * m_Noise5.CubicNoise2D(8 * NoiseCoordX, 8 * NoiseCoordZ);
+			
+			if ((Noise > 0) && (Noise < m_RiverWidthThreshold))
+			{
+				cChunkDef::SetBiome(a_BiomeMap, x, z, biRiver);
+			}
+		}  // for x
+	}  // for z
+}
+
+
+
+
+
+void cBioGenMultiStepMap::ApplyTemperatureHumidity(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap)
+{
+	IntMap TemperatureMap;
+	IntMap HumidityMap;
+	BuildTemperatureHumidityMaps(a_ChunkX, a_ChunkZ, TemperatureMap, HumidityMap);
+	
+	FreezeWaterBiomes(a_BiomeMap, TemperatureMap);
+	DecideLandBiomes(a_BiomeMap, TemperatureMap, HumidityMap);
+}
+
+
+
+
+
+void cBioGenMultiStepMap::Distort(int a_BlockX, int a_BlockZ, int & a_DistortedX, int & a_DistortedZ, int a_CellSize)
+{
+	double NoiseX = m_Noise3.CubicNoise2D(     (float)a_BlockX / a_CellSize,      (float)a_BlockZ / a_CellSize);
+	NoiseX += 0.5 * m_Noise2.CubicNoise2D(2 *  (float)a_BlockX / a_CellSize, 2 *  (float)a_BlockZ / a_CellSize);
+	NoiseX += 0.1 * m_Noise1.CubicNoise2D(16 * (float)a_BlockX / a_CellSize, 16 * (float)a_BlockZ / a_CellSize);
+	double NoiseZ = m_Noise6.CubicNoise2D(     (float)a_BlockX / a_CellSize,      (float)a_BlockZ / a_CellSize);
+	NoiseZ += 0.5 * m_Noise5.CubicNoise2D(2 *  (float)a_BlockX / a_CellSize, 2 *  (float)a_BlockZ / a_CellSize);
+	NoiseZ += 0.1 * m_Noise4.CubicNoise2D(16 * (float)a_BlockX / a_CellSize, 16 * (float)a_BlockZ / a_CellSize);
+	
+	a_DistortedX = a_BlockX + (int)(a_CellSize * 0.5 * NoiseX);
+	a_DistortedZ = a_BlockZ + (int)(a_CellSize * 0.5 * NoiseZ);
+}
+
+
+
+
+
+void cBioGenMultiStepMap::BuildTemperatureHumidityMaps(int a_ChunkX, int a_ChunkZ, IntMap & a_TemperatureMap, IntMap & a_HumidityMap)
+{
+	// Linear interpolation over 8x8 blocks; use double for better precision:
+	DblMap TemperatureMap;
+	DblMap HumidityMap;
+	for (int z = 0; z < 17; z += 8)
+	{
+		float NoiseCoordZ = (float)(a_ChunkZ * cChunkDef::Width + z) / m_LandBiomesSize;
+		for (int x = 0; x < 17; x += 8)
+		{
+			float NoiseCoordX = (float)(a_ChunkX * cChunkDef::Width + x) / m_LandBiomesSize;
+		
+			double NoiseT = m_Noise1.CubicNoise2D(    NoiseCoordX,     NoiseCoordZ);
+			NoiseT += 0.5 * m_Noise2.CubicNoise2D(2 * NoiseCoordX, 2 * NoiseCoordZ);
+			NoiseT += 0.1 * m_Noise3.CubicNoise2D(8 * NoiseCoordX, 8 * NoiseCoordZ);
+			TemperatureMap[x + 17 * z] = NoiseT;
+
+			double NoiseH = m_Noise4.CubicNoise2D(    NoiseCoordX,     NoiseCoordZ);
+			NoiseH += 0.5 * m_Noise5.CubicNoise2D(2 * NoiseCoordX, 2 * NoiseCoordZ);
+			NoiseH += 0.1 * m_Noise6.CubicNoise2D(8 * NoiseCoordX, 8 * NoiseCoordZ);
+			HumidityMap[x + 17 * z] = NoiseH;
+		}  // for x
+	}  // for z
+	LinearUpscale2DArrayInPlace(TemperatureMap, 17, 17, 8, 8);
+	LinearUpscale2DArrayInPlace(HumidityMap,    17, 17, 8, 8);
+	
+	// Re-map into integral values in [0 .. 255] range:
+	for (int idx = 0; idx < ARRAYCOUNT(a_TemperatureMap); idx++)
+	{
+		a_TemperatureMap[idx] = std::max(0, std::min(255, (int)(128 + TemperatureMap[idx] * 128)));
+		a_HumidityMap[idx]    = std::max(0, std::min(255, (int)(128 + HumidityMap[idx]    * 128)));
+	}
+}
+
+
+
+
+
+void cBioGenMultiStepMap::DecideLandBiomes(cChunkDef::BiomeMap & a_BiomeMap, const IntMap & a_TemperatureMap, const IntMap & a_HumidityMap)
+{
+	static const EMCSBiome BiomeMap[] =
+	{
+		//       0         1         2               3               4               5               6         7         8         9         10              11              12              13              14             15
+		/*  0 */ biTundra, biTundra, biTundra,       biTundra,       biPlains,       biPlains,       biPlains, biPlains, biPlains, biPlains, biDesert,       biDesert,      biDesert,       biDesert,       biDesert,      biDesert,
+		/*  1 */ biTundra, biTundra, biTundra,       biTundra,       biPlains,       biPlains,       biPlains, biPlains, biPlains, biPlains, biDesert,       biDesert,      biDesert,       biDesert,       biDesert,      biDesert,
+		/*  2 */ biTundra, biTundra, biTundra,       biTundra,       biPlains,       biExtremeHills, biPlains, biPlains, biPlains, biPlains, biDesert,       biDesert,      biDesertHills,  biDesertHills,  biDesert,      biDesert,
+		/*  3 */ biTundra, biTundra, biTundra,       biTundra,       biExtremeHills, biExtremeHills, biPlains, biPlains, biPlains, biPlains, biDesert,       biDesert,      biDesertHills,  biDesertHills,  biDesert,      biDesert,
+		/*  4 */ biTundra, biTundra, biIceMountains, biIceMountains, biExtremeHills, biExtremeHills, biPlains, biPlains, biPlains, biPlains, biForestHills,  biForestHills, biExtremeHills, biExtremeHills, biDesertHills, biDesert,
+		/*  5 */ biTundra, biTundra, biIceMountains, biIceMountains, biExtremeHills, biExtremeHills, biPlains, biPlains, biPlains, biPlains, biForestHills,  biForestHills, biExtremeHills, biExtremeHills, biDesertHills, biDesert,
+		/*  6 */ biTundra, biTundra, biIceMountains, biIceMountains, biForestHills,  biForestHills,  biForest, biForest, biForest, biForest, biForest,       biForestHills, biExtremeHills, biExtremeHills, biPlains,      biPlains,
+		/*  7 */ biTundra, biTundra, biIceMountains, biIceMountains, biForestHills,  biForestHills,  biForest, biForest, biForest, biForest, biForest,       biForestHills, biExtremeHills, biExtremeHills, biPlains,      biPlains,
+		/*  8 */ biTundra, biTundra, biTaiga,        biTaiga,        biForest,       biForest,       biForest, biForest, biForest, biForest, biForest,       biForestHills, biExtremeHills, biExtremeHills, biPlains,      biPlains,
+		/*  9 */ biTundra, biTundra, biTaiga,        biTaiga,        biForest,       biForest,       biForest, biForest, biForest, biForest, biForest,       biForestHills, biExtremeHills, biExtremeHills, biPlains,      biPlains,
+		/* 10 */ biTaiga,  biTaiga,  biTaiga,        biIceMountains, biForestHills,  biForestHills,  biForest, biForest, biForest, biForest, biJungle,       biJungle,      biSwampland,    biSwampland,    biSwampland,   biSwampland,
+		/* 11 */ biTaiga,  biTaiga,  biIceMountains, biIceMountains, biExtremeHills, biForestHills,  biForest, biForest, biForest, biForest, biJungle,       biJungle,      biSwampland,    biSwampland,    biSwampland,   biSwampland,
+		/* 12 */ biTaiga,  biTaiga,  biIceMountains, biIceMountains, biExtremeHills, biJungleHills,  biJungle, biJungle, biJungle, biJungle, biJungle,       biJungle,      biSwampland,    biSwampland,    biSwampland,   biSwampland,
+		/* 13 */ biTaiga,  biTaiga,  biTaiga,        biIceMountains, biJungleHills,  biJungleHills,  biJungle, biJungle, biJungle, biJungle, biJungle,       biJungle,      biSwampland,    biSwampland,    biSwampland,   biSwampland,
+		/* 14 */ biTaiga,  biTaiga,  biTaiga,        biTaiga,        biJungle,       biJungle,       biJungle, biJungle, biJungle, biJungle, biJungle,       biJungle,      biSwampland,    biSwampland,    biSwampland,   biSwampland,
+		/* 15 */ biTaiga,  biTaiga,  biTaiga,        biTaiga,        biJungle,       biJungle,       biJungle, biJungle, biJungle, biJungle, biJungle,       biJungle,      biSwampland,    biSwampland,    biSwampland,   biSwampland,
+	} ;
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		int idxZ = 17 * z;
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			if (cChunkDef::GetBiome(a_BiomeMap, x, z) != -1)
+			{
+				// Already set before
+				continue;
+			}
+			int idx = idxZ + x;
+			int Temperature = a_TemperatureMap[idx] / 16;  // -> [0..15] range
+			int Humidity    = a_HumidityMap[idx]    / 16;  // -> [0..15] range
+			cChunkDef::SetBiome(a_BiomeMap, x, z, BiomeMap[Temperature + 16 * Humidity]);
+		}  // for x
+	}  // for z
+}
+
+
+
+
+
+void cBioGenMultiStepMap::FreezeWaterBiomes(cChunkDef::BiomeMap & a_BiomeMap, const IntMap & a_TemperatureMap)
+{
+	int idx = 0;
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int x = 0; x < cChunkDef::Width; x++, idx++)
+		{
+			if (a_TemperatureMap[idx] > 4 * 16)
+			{
+				// Not frozen
+				continue;
+			}
+			switch (cChunkDef::GetBiome(a_BiomeMap, x, z))
+			{
+				case biRiver: cChunkDef::SetBiome(a_BiomeMap, x, z, biFrozenRiver); break;
+				case biOcean: cChunkDef::SetBiome(a_BiomeMap, x, z, biFrozenOcean); break;
+			}
+		}  // for x
+		idx += 1;
+	}  // for z
+}
+
+
+
+

src/Generating/BioGen.h

@@ -0,0 +1,230 @@
+
+// BioGen.h
+
+/*
+Interfaces to the various biome generators:
+	- cBioGenConstant
+	- cBioGenCheckerboard
+	- cBioGenDistortedVoronoi
+*/
+
+
+
+
+
+#pragma once
+
+#include "ComposableGenerator.h"
+#include "../Noise.h"
+
+
+
+
+
+class cBioGenConstant :
+	public cBiomeGen
+{
+public:
+	cBioGenConstant(void) : m_Biome(biPlains) {}
+	
+protected:
+
+	EMCSBiome m_Biome;
+
+	// cBiomeGen overrides:
+	virtual void GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap) override;
+	virtual void InitializeBiomeGen(cIniFile & a_IniFile) override;
+} ;
+
+
+
+
+
+/// A simple cache that stores N most recently generated chunks' biomes; N being settable upon creation
+class cBioGenCache :
+	public cBiomeGen
+{
+	typedef cBiomeGen super;
+	
+public:
+	cBioGenCache(cBiomeGen * a_BioGenToCache, int a_CacheSize);  // Doesn't take ownership of a_BioGenToCache
+	~cBioGenCache();
+	
+protected:
+
+	cBiomeGen * m_BioGenToCache;
+	
+	struct sCacheData
+	{
+		int m_ChunkX;
+		int m_ChunkZ;
+		cChunkDef::BiomeMap m_BiomeMap;
+	} ;
+	
+	// To avoid moving large amounts of data for the MRU behavior, we MRU-ize indices to an array of the actual data
+	int          m_CacheSize;
+	int *        m_CacheOrder;  // MRU-ized order, indices into m_CacheData array
+	sCacheData * m_CacheData;   // m_CacheData[m_CacheOrder[0]] is the most recently used
+	
+	// Cache statistics
+	int m_NumHits;
+	int m_NumMisses;
+	int m_TotalChain;  // Number of cache items walked to get to a hit (only added for hits)
+	
+	virtual void GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap) override;
+	virtual void InitializeBiomeGen(cIniFile & a_IniFile) override;
+} ;
+
+
+
+
+
+/// Base class for generators that use a list of available biomes. This class takes care of the list.
+class cBiomeGenList :
+	public cBiomeGen
+{
+	typedef cBiomeGen super;
+	
+protected:
+	// List of biomes that the generator is allowed to generate:
+	typedef std::vector<EMCSBiome> EMCSBiomes;
+	EMCSBiomes m_Biomes;
+	int        m_BiomesCount;  // Pulled out of m_Biomes for faster access
+	
+	/// Parses the INI file setting string into m_Biomes.
+	void InitializeBiomes(const AString & a_Biomes);
+} ;
+
+
+
+
+
+class cBioGenCheckerboard :
+	public cBiomeGenList
+{
+	typedef cBiomeGenList super;
+	
+protected:
+	int m_BiomeSize;
+	
+	// cBiomeGen overrides:
+	virtual void GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap) override;
+	virtual void InitializeBiomeGen(cIniFile & a_IniFile) override;
+} ;
+
+
+
+
+
+class cBioGenVoronoi :
+	public cBiomeGenList
+{
+	typedef cBiomeGenList super;
+	
+public:
+	cBioGenVoronoi(int a_Seed) :
+		m_Noise(a_Seed)
+	{
+	}
+	
+protected:
+	int m_CellSize;
+	
+	cNoise m_Noise;
+
+	// cBiomeGen overrides:
+	virtual void GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap) override;
+	virtual void InitializeBiomeGen(cIniFile & a_IniFile) override;
+	
+	EMCSBiome VoronoiBiome(int a_BlockX, int a_BlockZ);
+} ;
+
+
+
+
+
+class cBioGenDistortedVoronoi :
+	public cBioGenVoronoi
+{
+	typedef cBioGenVoronoi super;
+public:
+	cBioGenDistortedVoronoi(int a_Seed) :
+		cBioGenVoronoi(a_Seed)
+	{
+	}
+
+protected:
+	// cBiomeGen overrides:
+	virtual void GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap) override;
+	virtual void InitializeBiomeGen(cIniFile & a_IniFile) override;
+	
+	/// Distorts the coords using a Perlin-like noise
+	void Distort(int a_BlockX, int a_BlockZ, int & a_DistortedX, int & a_DistortedZ);
+} ;
+
+
+
+
+
+class cBioGenMultiStepMap :
+	public cBiomeGen
+{
+	typedef cBiomeGen super;
+	
+public:
+	cBioGenMultiStepMap(int a_Seed);
+	
+protected:
+	// Noises used for composing the perlin-noise:
+	cNoise m_Noise1;
+	cNoise m_Noise2;
+	cNoise m_Noise3;
+	cNoise m_Noise4;
+	cNoise m_Noise5;
+	cNoise m_Noise6;
+	
+	int    m_Seed;
+	int    m_OceanCellSize;
+	int    m_MushroomIslandSize;
+	int    m_RiverCellSize;
+	double m_RiverWidthThreshold;
+	float  m_LandBiomesSize;
+	
+	typedef int    IntMap[17 * 17];  // x + 17 * z, expected trimmed into [0..255] range
+	typedef double DblMap[17 * 17];  // x + 17 * z, expected trimmed into [0..1] range
+		
+	// cBiomeGen overrides:
+	virtual void GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap) override;
+	virtual void InitializeBiomeGen(cIniFile & a_IniFile) override;
+	
+	/** Step 1: Decides between ocean, land and mushroom, using a DistVoronoi with special conditions and post-processing for mushroom islands
+	Sets biomes to biOcean, -1 (i.e. land), biMushroomIsland or biMushroomShore
+	*/
+	void DecideOceanLandMushroom(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap);
+	
+	/** Step 2: Add rivers to the land
+	Flips some "-1" biomes into biRiver
+	*/
+	void AddRivers(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap);
+	
+	/** Step 3: Decide land biomes using a temperature / humidity map; freeze ocean / river in low temperatures.
+	Flips all remaining "-1" biomes into land biomes. Also flips some biOcean and biRiver into biFrozenOcean, biFrozenRiver, based on temp map.
+	*/
+	void ApplyTemperatureHumidity(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap);
+	
+	/// Distorts the coords using a Perlin-like noise, with a specified cell-size
+	void Distort(int a_BlockX, int a_BlockZ, int & a_DistortedX, int & a_DistortedZ, int a_CellSize);
+	
+	/// Builds two Perlin-noise maps, one for temperature, the other for humidity. Trims both into [0..255] range
+	void BuildTemperatureHumidityMaps(int a_ChunkX, int a_ChunkZ, IntMap & a_TemperatureMap, IntMap & a_HumidityMap);
+	
+	/// Flips all remaining "-1" biomes into land biomes using the two maps
+	void DecideLandBiomes(cChunkDef::BiomeMap & a_BiomeMap, const IntMap & a_TemperatureMap, const IntMap & a_HumidityMap);
+	
+	/// Flips biOcean and biRiver into biFrozenOcean and biFrozenRiver if the temperature is too low
+	void FreezeWaterBiomes(cChunkDef::BiomeMap & a_BiomeMap, const IntMap & a_TemperatureMap);
+} ;
+
+
+
+

src/Generating/Caves.cpp

@@ -0,0 +1,970 @@
+
+// Caves.cpp
+
+// Implements the various cave structure generators:
+//   - cStructGenWormNestCaves
+//   - cStructGenDualRidgeCaves
+//   - cStructGenMarbleCaves
+//   - cStructGenNetherCaves
+
+/*
+WormNestCave generator:
+Caves are generated in "nests" - groups of tunnels generated from a single point.
+For each chunk, all the nests that could intersect it are generated.
+For each nest, first the schematic structure is generated (tunnel from ... to ..., branch, tunnel2 from ... to ...)
+Then each tunnel is randomized by inserting points in between its ends.
+Finally each tunnel is smoothed and Bresenham-3D-ed so that it is a collection of spheres with their centers next to each other.
+When the tunnels are ready, they are simply carved into the chunk, one by one.
+To optimize, each tunnel keeps track of its bounding box, so that it can be skipped for chunks that don't intersect it.
+
+MarbleCaves generator:
+For each voxel a 3D noise function is evaluated, if the value crosses a boundary, the voxel is dug out, otherwise it is kept.
+Problem with this is the amount of CPU work needed for each chunk.
+Also the overall shape of the generated holes is unsatisfactory - there are whole "sheets" of holes in the ground.
+
+DualRidgeCaves generator:
+Instead of evaluating a single noise function, two different noise functions are multiplied. This produces
+regular tunnels instead of sheets. However due to the sheer amount of CPU work needed, the noise functions need to be
+reduced in complexity in order for this generator to be useful, so the caves' shapes are "bubbly" at best.
+*/
+
+#include "Globals.h"
+#include "Caves.h"
+
+
+
+
+
+/// How many nests in each direction are generated for a given chunk. Must be an even number
+#define NEIGHBORHOOD_SIZE 8
+
+
+
+
+
+const int MIN_RADIUS = 3;
+const int MAX_RADIUS = 8;
+
+
+
+
+
+struct cCaveDefPoint
+{
+	int m_BlockX;
+	int m_BlockY;
+	int m_BlockZ;
+	int m_Radius;
+	
+	cCaveDefPoint(int a_BlockX, int a_BlockY, int a_BlockZ, int a_Radius) :
+		m_BlockX(a_BlockX),
+		m_BlockY(a_BlockY),
+		m_BlockZ(a_BlockZ),
+		m_Radius(a_Radius)
+	{
+	}
+} ;
+
+typedef std::vector<cCaveDefPoint> cCaveDefPoints;
+
+
+
+
+
+/// A single non-branching tunnel of a WormNestCave
+class cCaveTunnel
+{
+	// The bounding box, including the radii around defpoints:
+	int m_MinBlockX, m_MaxBlockX;
+	int m_MinBlockY, m_MaxBlockY;
+	int m_MinBlockZ, m_MaxBlockZ;
+	
+	/// Generates the shaping defpoints for the ravine, based on the ravine block coords and noise
+	void Randomize(cNoise & a_Noise);
+	
+	/// Refines (adds and smooths) defpoints from a_Src into a_Dst; returns false if no refinement possible (segments too short)
+	bool RefineDefPoints(const cCaveDefPoints & a_Src, cCaveDefPoints & a_Dst);
+	
+	/// Does rounds of smoothing, two passes of RefineDefPoints(), as long as they return true
+	void Smooth(void);
+	
+	/// Linearly interpolates the points so that the maximum distance between two neighbors is max 1 block
+	void FinishLinear(void);
+	
+	/// Calculates the bounding box of the points present
+	void CalcBoundingBox(void);
+	
+public:
+	cCaveDefPoints m_Points;
+
+	cCaveTunnel(
+		int a_BlockStartX, int a_BlockStartY, int a_BlockStartZ, int a_StartRadius,
+		int a_BlockEndX,   int a_BlockEndY,   int a_BlockEndZ,   int a_EndRadius,
+		cNoise & a_Noise
+	);
+	
+	/// Carves the tunnel into the chunk specified
+	void ProcessChunk(
+		int a_ChunkX, int a_ChunkZ, 
+		cChunkDef::BlockTypes & a_BlockTypes, 
+		cChunkDef::HeightMap & a_HeightMap
+	);
+	
+	#ifdef _DEBUG
+	AString ExportAsSVG(int a_Color, int a_OffsetX, int a_OffsetZ) const;
+	#endif  // _DEBUG
+} ;
+
+typedef std::vector<cCaveTunnel *> cCaveTunnels;
+
+
+
+
+
+/// A collection of connected tunnels, possibly branching.
+class cStructGenWormNestCaves::cCaveSystem
+{
+public:
+	// The generating block position; is read directly in cStructGenWormNestCaves::GetCavesForChunk()
+	int m_BlockX;
+	int m_BlockZ;
+	
+	cCaveSystem(int a_BlockX, int a_BlockZ, int a_MaxOffset, int a_Size, cNoise & a_Noise);
+	~cCaveSystem();
+	
+	/// Carves the cave system into the chunk specified
+	void ProcessChunk(
+		int a_ChunkX, int a_ChunkZ, 
+		cChunkDef::BlockTypes & a_BlockTypes, 
+		cChunkDef::HeightMap & a_HeightMap
+	);
+	
+	#ifdef _DEBUG
+	AString ExportAsSVG(int a_Color, int a_OffsetX, int a_OffsetZ) const;
+	#endif  // _DEBUG
+
+protected:
+	int m_Size;
+	cCaveTunnels m_Tunnels;
+	
+	void Clear(void);
+
+	/// Generates a_Segment successive tunnels, with possible branches. Generates the same output for the same [x, y, z, a_Segments]
+	void GenerateTunnelsFromPoint(
+		int a_OriginX, int a_OriginY, int a_OriginZ, 
+		cNoise & a_Noise, int a_Segments
+	);
+	
+	/// Returns a radius based on the location provided.
+	int GetRadius(cNoise & a_Noise, int a_OriginX, int a_OriginY, int a_OriginZ);
+} ;
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cCaveTunnel:
+
+cCaveTunnel::cCaveTunnel(
+	int a_BlockStartX, int a_BlockStartY, int a_BlockStartZ, int a_StartRadius,
+	int a_BlockEndX,   int a_BlockEndY,   int a_BlockEndZ,   int a_EndRadius,
+	cNoise & a_Noise
+)
+{
+	m_Points.push_back(cCaveDefPoint(a_BlockStartX, a_BlockStartY, a_BlockStartZ, a_StartRadius));
+	m_Points.push_back(cCaveDefPoint(a_BlockEndX,   a_BlockEndY,   a_BlockEndZ,   a_EndRadius));
+	
+	if ((a_BlockStartY <= 0) && (a_BlockEndY <= 0))
+	{
+		// Don't bother detailing this cave, it's under the world anyway
+		return;
+	}
+	
+	Randomize(a_Noise);
+	Smooth();
+	
+	// We know that the linear finishing won't affect the bounding box, so let's calculate it now, as we have less data:
+	CalcBoundingBox();
+	
+	FinishLinear();
+}
+
+
+
+
+
+void cCaveTunnel::Randomize(cNoise & a_Noise)
+{
+	// Repeat 4 times:
+	for (int i = 0; i < 4; i++)
+	{
+		// For each already present point, insert a point in between it and its predecessor, shifted randomly.
+		int PrevX = m_Points.front().m_BlockX;
+		int PrevY = m_Points.front().m_BlockY;
+		int PrevZ = m_Points.front().m_BlockZ;
+		int PrevR = m_Points.front().m_Radius;
+		cCaveDefPoints Pts;
+		Pts.reserve(m_Points.size() * 2 + 1);
+		Pts.push_back(m_Points.front());
+		for (cCaveDefPoints::const_iterator itr = m_Points.begin() + 1, end = m_Points.end(); itr != end; ++itr)
+		{
+			int Random = a_Noise.IntNoise3DInt(PrevX, PrevY, PrevZ + i) / 11;
+			int len = (PrevX - itr->m_BlockX) * (PrevX - itr->m_BlockX);
+			len += (PrevY - itr->m_BlockY) * (PrevY - itr->m_BlockY);
+			len += (PrevZ - itr->m_BlockZ) * (PrevZ - itr->m_BlockZ);
+			len = 3 * (int)sqrt((double)len) / 4;
+			int Rad = std::min(MAX_RADIUS, std::max(MIN_RADIUS, (PrevR + itr->m_Radius) / 2 + (Random % 3) - 1));
+			Random /= 4;
+			int x = (itr->m_BlockX + PrevX) / 2 + (Random % (len + 1) - len / 2);
+			Random /= 256;
+			int y = (itr->m_BlockY + PrevY) / 2 + (Random % (len / 2 + 1) - len / 4);
+			Random /= 256;
+			int z = (itr->m_BlockZ + PrevZ) / 2 + (Random % (len + 1) - len / 2);
+			Pts.push_back(cCaveDefPoint(x, y, z, Rad));
+			Pts.push_back(*itr);
+			PrevX = itr->m_BlockX;
+			PrevY = itr->m_BlockY;
+			PrevZ = itr->m_BlockZ;
+			PrevR = itr->m_Radius;
+		}
+		std::swap(Pts, m_Points);
+	}
+}
+
+
+
+
+
+bool cCaveTunnel::RefineDefPoints(const cCaveDefPoints & a_Src, cCaveDefPoints & a_Dst)
+{
+	// Smoothing: for each line segment, add points on its 1/4 lengths
+	bool res = false;
+	int Num = a_Src.size() - 2;  // this many intermediary points
+	a_Dst.clear();
+	a_Dst.reserve(Num * 2 + 2);
+	cCaveDefPoints::const_iterator itr = a_Src.begin() + 1;
+	a_Dst.push_back(a_Src.front());
+	int PrevX = a_Src.front().m_BlockX;
+	int PrevY = a_Src.front().m_BlockY;
+	int PrevZ = a_Src.front().m_BlockZ;
+	int PrevR = a_Src.front().m_Radius;
+	for (int i = 0; i <= Num; ++i, ++itr)
+	{
+		int dx = itr->m_BlockX - PrevX;
+		int dy = itr->m_BlockY - PrevY;
+		int dz = itr->m_BlockZ - PrevZ;
+		if (abs(dx) + abs(dz) + abs(dy) < 6)
+		{
+			// Too short a segment to smooth-subdivide into quarters
+			PrevX = itr->m_BlockX;
+			PrevY = itr->m_BlockY;
+			PrevZ = itr->m_BlockZ;
+			PrevR = itr->m_Radius;
+			continue;
+		}
+		int dr = itr->m_Radius - PrevR;
+		int Rad1 = std::max(PrevR + 1 * dr / 4, 1);
+		int Rad2 = std::max(PrevR + 3 * dr / 4, 1);
+		a_Dst.push_back(cCaveDefPoint(PrevX + 1 * dx / 4, PrevY + 1 * dy / 4, PrevZ + 1 * dz / 4, Rad1));
+		a_Dst.push_back(cCaveDefPoint(PrevX + 3 * dx / 4, PrevY + 3 * dy / 4, PrevZ + 3 * dz / 4, Rad2));
+		PrevX = itr->m_BlockX;
+		PrevY = itr->m_BlockY;
+		PrevZ = itr->m_BlockZ;
+		PrevR = itr->m_Radius;
+		res = true;
+	}
+	a_Dst.push_back(a_Src.back());
+	return res && (a_Src.size() < a_Dst.size());
+}
+
+
+
+
+
+void cCaveTunnel::Smooth(void)
+{
+	cCaveDefPoints Pts;
+	while (true)
+	{
+		if (!RefineDefPoints(m_Points, Pts))
+		{
+			std::swap(Pts, m_Points);
+			return;
+		}
+		if (!RefineDefPoints(Pts, m_Points))
+		{
+			return;
+		}
+	}
+}
+
+
+
+
+
+void cCaveTunnel::FinishLinear(void)
+{
+	// For each segment, use Bresenham's 3D line algorithm to draw a "line" of defpoints
+	cCaveDefPoints Pts;
+	std::swap(Pts, m_Points);
+	
+	m_Points.reserve(Pts.size() * 3);
+	int PrevX = Pts.front().m_BlockX;
+	int PrevY = Pts.front().m_BlockY;
+	int PrevZ = Pts.front().m_BlockZ;
+	for (cCaveDefPoints::const_iterator itr = Pts.begin() + 1, end = Pts.end(); itr != end; ++itr)
+	{
+		int x1 = itr->m_BlockX;
+		int y1 = itr->m_BlockY;
+		int z1 = itr->m_BlockZ;
+		int dx = abs(x1 - PrevX);
+		int dy = abs(y1 - PrevY);
+		int dz = abs(z1 - PrevZ);
+		int sx = (PrevX < x1) ? 1 : -1;
+		int sy = (PrevY < y1) ? 1 : -1;
+		int sz = (PrevZ < z1) ? 1 : -1;
+		int err = dx - dz;
+		int R = itr->m_Radius;
+
+		if (dx >= std::max(dy, dz))  // x dominant
+		{
+			int yd = dy - dx / 2;
+			int zd = dz - dx / 2;
+
+			while (true)
+			{
+				m_Points.push_back(cCaveDefPoint(PrevX, PrevY, PrevZ, R));
+
+				if (PrevX == x1)
+				{
+					break;
+				}
+
+				if (yd >= 0)  // move along y
+				{
+					PrevY += sy;
+					yd -= dx;
+				}
+
+				if (zd >= 0)  // move along z
+				{
+					PrevZ += sz;
+					zd -= dx;
+				}
+
+				// move along x
+				PrevX  += sx;
+				yd += dy;
+				zd += dz;
+			}
+		}
+		else if (dy >= std::max(dx, dz))  // y dominant
+		{
+			int xd = dx - dy / 2;
+			int zd = dz - dy / 2;
+
+			while (true)
+			{
+				m_Points.push_back(cCaveDefPoint(PrevX, PrevY, PrevZ, R));
+
+				if (PrevY == y1)
+				{
+					break;
+				}
+
+				if (xd >= 0)  // move along x
+				{
+					PrevX += sx;
+					xd -= dy;
+				}
+
+				if (zd >= 0)  // move along z
+				{
+					PrevZ += sz;
+					zd -= dy;
+				}
+
+				// move along y
+				PrevY += sy;
+				xd += dx;
+				zd += dz;
+			}
+		}
+		else
+		{
+			// z dominant
+			ASSERT(dz >= std::max(dx, dy));
+			int xd = dx - dz / 2;
+			int yd = dy - dz / 2;
+
+			while (true)
+			{
+				m_Points.push_back(cCaveDefPoint(PrevX, PrevY, PrevZ, R));
+
+				if (PrevZ == z1)
+				{
+					break;
+				}
+
+				if (xd >= 0)  // move along x
+				{
+					PrevX += sx;
+					xd -= dz;
+				}
+
+				if (yd >= 0)  // move along y
+				{
+					PrevY += sy;
+					yd -= dz;
+				}
+				
+				// move along z
+				PrevZ += sz;
+				xd += dx;
+				yd += dy;
+			}
+		}  // if (which dimension is dominant)
+	}  // for itr
+}
+
+
+
+
+
+void cCaveTunnel::CalcBoundingBox(void)
+{
+	m_MinBlockX = m_MaxBlockX = m_Points.front().m_BlockX;
+	m_MinBlockY = m_MaxBlockY = m_Points.front().m_BlockY;
+	m_MinBlockZ = m_MaxBlockZ = m_Points.front().m_BlockZ;
+	for (cCaveDefPoints::const_iterator itr = m_Points.begin() + 1, end = m_Points.end(); itr != end; ++itr)
+	{
+		m_MinBlockX = std::min(m_MinBlockX, itr->m_BlockX - itr->m_Radius);
+		m_MaxBlockX = std::max(m_MaxBlockX, itr->m_BlockX + itr->m_Radius);
+		m_MinBlockY = std::min(m_MinBlockY, itr->m_BlockY - itr->m_Radius);
+		m_MaxBlockY = std::max(m_MaxBlockY, itr->m_BlockY + itr->m_Radius);
+		m_MinBlockZ = std::min(m_MinBlockZ, itr->m_BlockZ - itr->m_Radius);
+		m_MaxBlockZ = std::max(m_MaxBlockZ, itr->m_BlockZ + itr->m_Radius);
+	}  // for itr - m_Points[]
+}
+
+
+
+
+
+void cCaveTunnel::ProcessChunk(
+	int a_ChunkX, int a_ChunkZ, 
+	cChunkDef::BlockTypes & a_BlockTypes, 
+	cChunkDef::HeightMap & a_HeightMap
+)
+{
+	int BaseX = a_ChunkX * cChunkDef::Width;
+	int BaseZ = a_ChunkZ * cChunkDef::Width;
+	if (
+		(BaseX > m_MaxBlockX) || (BaseX + cChunkDef::Width < m_MinBlockX) ||
+		(BaseX > m_MaxBlockX) || (BaseX + cChunkDef::Width < m_MinBlockX)
+	)
+	{
+		// Tunnel does not intersect the chunk at all, bail out
+		return;
+	}
+
+	int BlockStartX = a_ChunkX * cChunkDef::Width;
+	int BlockStartZ = a_ChunkZ * cChunkDef::Width;
+	int BlockEndX = BlockStartX + cChunkDef::Width;
+	int BlockEndZ = BlockStartZ + cChunkDef::Width;
+	for (cCaveDefPoints::const_iterator itr = m_Points.begin(), end = m_Points.end(); itr != end; ++itr)
+	{
+		if (
+			(itr->m_BlockX + itr->m_Radius < BlockStartX) ||
+			(itr->m_BlockX - itr->m_Radius > BlockEndX) ||
+			(itr->m_BlockZ + itr->m_Radius < BlockStartZ) ||
+			(itr->m_BlockZ - itr->m_Radius > BlockEndZ)
+		)
+		{
+			// Cannot intersect, bail out early
+			continue;
+		}
+		
+		// Carve out a sphere around the xyz point, m_Radius in diameter; skip 3/7 off the top and bottom:
+		int DifX = itr->m_BlockX - BlockStartX;  // substitution for faster calc
+		int DifY = itr->m_BlockY;
+		int DifZ = itr->m_BlockZ - BlockStartZ;  // substitution for faster calc
+		int Bottom = std::max(itr->m_BlockY - 3 * itr->m_Radius / 7, 1);
+		int Top    = std::min(itr->m_BlockY + 3 * itr->m_Radius / 7, (int)(cChunkDef::Height));
+		int SqRad  = itr->m_Radius * itr->m_Radius;
+		for (int z = 0; z < cChunkDef::Width; z++) for (int x = 0; x < cChunkDef::Width; x++) 
+		{
+			for (int y = Bottom; y <= Top; y++)
+			{
+				int SqDist = (DifX - x) * (DifX - x) + (DifY - y) * (DifY - y) + (DifZ - z) * (DifZ - z);
+				if (4 * SqDist <= SqRad)
+				{
+					switch (cChunkDef::GetBlock(a_BlockTypes, x, y, z))
+					{
+						// Only carve out these specific block types
+						case E_BLOCK_DIRT:
+						case E_BLOCK_GRASS:
+						case E_BLOCK_STONE:
+						case E_BLOCK_COBBLESTONE:
+						case E_BLOCK_GRAVEL:
+						case E_BLOCK_SAND:
+						case E_BLOCK_SANDSTONE:
+						case E_BLOCK_NETHERRACK:
+						case E_BLOCK_COAL_ORE:
+						case E_BLOCK_IRON_ORE:
+						case E_BLOCK_GOLD_ORE:
+						case E_BLOCK_DIAMOND_ORE:
+						case E_BLOCK_REDSTONE_ORE:
+						case E_BLOCK_REDSTONE_ORE_GLOWING:
+						{
+							cChunkDef::SetBlock(a_BlockTypes, x, y, z, E_BLOCK_AIR);
+							break;
+						}
+						default: break;
+					}
+				}
+			}  // for y
+		}  // for x, z
+	}  // for itr - m_Points[]
+	
+	/*
+	#ifdef _DEBUG		
+	// For debugging purposes, outline the shape of the cave using glowstone, *after* carving the entire cave:
+	for (cCaveDefPoints::const_iterator itr = m_Points.begin(), end = m_Points.end(); itr != end; ++itr)
+	{
+		int DifX = itr->m_BlockX - BlockStartX;  // substitution for faster calc
+		int DifZ = itr->m_BlockZ - BlockStartZ;  // substitution for faster calc
+		if (
+			(DifX >= 0) && (DifX < cChunkDef::Width) &&
+			(itr->m_BlockY > 0) && (itr->m_BlockY < cChunkDef::Height) &&
+			(DifZ >= 0) && (DifZ < cChunkDef::Width)
+		)
+		{
+			cChunkDef::SetBlock(a_BlockTypes, DifX, itr->m_BlockY, DifZ, E_BLOCK_GLOWSTONE);
+		}
+	}  // for itr - m_Points[]
+	#endif  // _DEBUG
+	//*/
+}
+
+
+
+
+
+#ifdef _DEBUG
+AString cCaveTunnel::ExportAsSVG(int a_Color, int a_OffsetX, int a_OffsetZ) const
+{
+	AString SVG;
+	SVG.reserve(m_Points.size() * 20 + 200);
+  AppendPrintf(SVG, "<path style=\"fill:none;stroke:#%06x;stroke-width:1px;\"\nd=\"", a_Color);
+  char Prefix = 'M';  // The first point needs "M" prefix, all the others need "L"
+  for (cCaveDefPoints::const_iterator itr = m_Points.begin(); itr != m_Points.end(); ++itr)
+  {
+		AppendPrintf(SVG, "%c %d,%d ", Prefix, a_OffsetX + itr->m_BlockX, a_OffsetZ + itr->m_BlockZ);
+		Prefix = 'L';
+  }
+  SVG.append("\"/>\n");
+	return SVG;
+}
+#endif  // _DEBUG
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cStructGenWormNestCaves::cCaveSystem:
+
+cStructGenWormNestCaves::cCaveSystem::cCaveSystem(int a_BlockX, int a_BlockZ, int a_MaxOffset, int a_Size, cNoise & a_Noise) :
+	m_BlockX(a_BlockX),
+	m_BlockZ(a_BlockZ),
+	m_Size(a_Size)
+{
+	int Num = 1 + a_Noise.IntNoise2DInt(a_BlockX, a_BlockZ) % 3;
+	for (int i = 0; i < Num; i++)
+	{
+		int OriginX = a_BlockX + (a_Noise.IntNoise3DInt(13 * a_BlockX, 17 * a_BlockZ, 11 * i) / 19) % a_MaxOffset;
+		int OriginZ = a_BlockZ + (a_Noise.IntNoise3DInt(17 * a_BlockX, 13 * a_BlockZ, 11 * i) / 23) % a_MaxOffset;
+		int OriginY  = 20 + (a_Noise.IntNoise3DInt(19 * a_BlockX, 13 * a_BlockZ, 11 * i) / 17) % 20;
+		
+		// Generate three branches from the origin point:
+		// The tunnels generated depend on X, Y, Z and Branches,
+		// for the same set of numbers it generates the same offsets!
+		// That's why we add a +1 to X in the third line
+		GenerateTunnelsFromPoint(OriginX,     OriginY, OriginZ, a_Noise, 3);
+		GenerateTunnelsFromPoint(OriginX,     OriginY, OriginZ, a_Noise, 2);
+		GenerateTunnelsFromPoint(OriginX + 1, OriginY, OriginZ, a_Noise, 3);
+	}
+}
+
+
+
+
+
+cStructGenWormNestCaves::cCaveSystem::~cCaveSystem()
+{
+	Clear();
+}
+
+
+
+
+
+
+void cStructGenWormNestCaves::cCaveSystem::ProcessChunk(
+	int a_ChunkX, int a_ChunkZ, 
+	cChunkDef::BlockTypes & a_BlockTypes, 
+	cChunkDef::HeightMap & a_HeightMap
+)
+{
+	for (cCaveTunnels::const_iterator itr = m_Tunnels.begin(), end = m_Tunnels.end(); itr != end; ++itr)
+	{
+		(*itr)->ProcessChunk(a_ChunkX, a_ChunkZ, a_BlockTypes, a_HeightMap);
+	}  // for itr - m_Tunnels[]
+}
+
+
+
+
+
+#ifdef _DEBUG
+AString cStructGenWormNestCaves::cCaveSystem::ExportAsSVG(int a_Color, int a_OffsetX, int a_OffsetZ) const
+{
+	AString SVG;
+	SVG.reserve(512 * 1024);
+	for (cCaveTunnels::const_iterator itr = m_Tunnels.begin(), end = m_Tunnels.end(); itr != end; ++itr)
+	{
+		SVG.append((*itr)->ExportAsSVG(a_Color, a_OffsetX, a_OffsetZ));
+	}  // for itr - m_Tunnels[]
+
+	// Base point highlight:
+	AppendPrintf(SVG, "<path style=\"fill:none;stroke:#ff0000;stroke-width:1px;\"\nd=\"M %d,%d L %d,%d\"/>\n",
+		a_OffsetX + m_BlockX - 5, a_OffsetZ + m_BlockZ, a_OffsetX + m_BlockX + 5, a_OffsetZ + m_BlockZ
+	);
+	AppendPrintf(SVG, "<path style=\"fill:none;stroke:#ff0000;stroke-width:1px;\"\nd=\"M %d,%d L %d,%d\"/>\n",
+		a_OffsetX + m_BlockX, a_OffsetZ + m_BlockZ - 5, a_OffsetX + m_BlockX, a_OffsetZ + m_BlockZ + 5
+	);
+	
+	// A gray line from the base point to the first point of the ravine, for identification:
+	AppendPrintf(SVG, "<path style=\"fill:none;stroke:#cfcfcf;stroke-width:1px;\"\nd=\"M %d,%d L %d,%d\"/>\n",
+		a_OffsetX + m_BlockX, a_OffsetZ + m_BlockZ, 
+		a_OffsetX + m_Tunnels.front()->m_Points.front().m_BlockX, 
+		a_OffsetZ + m_Tunnels.front()->m_Points.front().m_BlockZ
+	);
+	
+	// Offset guides:
+	if (a_OffsetX > 0)
+	{
+		AppendPrintf(SVG, "<path style=\"fill:none;stroke:#0000ff;stroke-width:1px;\"\nd=\"M %d,0 L %d,1024\"/>\n",
+			a_OffsetX, a_OffsetX
+		);
+	}
+	if (a_OffsetZ > 0)
+	{
+		AppendPrintf(SVG, "<path style=\"fill:none;stroke:#0000ff;stroke-width:1px;\"\nd=\"M 0,%d L 1024,%d\"/>\n",
+			a_OffsetZ, a_OffsetZ
+		);
+	}
+	
+	return SVG;
+}
+#endif  // _DEBUG
+
+
+
+
+
+void cStructGenWormNestCaves::cCaveSystem::Clear(void)
+{
+	for (cCaveTunnels::const_iterator itr = m_Tunnels.begin(), end = m_Tunnels.end(); itr != end; ++itr)
+	{
+		delete *itr;
+	}
+	m_Tunnels.clear();
+}
+
+
+
+
+
+void cStructGenWormNestCaves::cCaveSystem::GenerateTunnelsFromPoint(
+	int a_OriginX, int a_OriginY, int a_OriginZ, 
+	cNoise & a_Noise, int a_NumSegments
+)
+{
+	int DoubleSize = m_Size * 2;
+	int Radius = GetRadius(a_Noise, a_OriginX + a_OriginY, a_OriginY + a_OriginZ, a_OriginZ + a_OriginX);
+	for (int i = a_NumSegments - 1; i >= 0; --i)
+	{
+		int EndX = a_OriginX + (((a_Noise.IntNoise3DInt(a_OriginX, a_OriginY, a_OriginZ + 11 * a_NumSegments) / 7) % DoubleSize) - m_Size) / 2;
+		int EndY = a_OriginY + (((a_Noise.IntNoise3DInt(a_OriginY, 13 * a_NumSegments, a_OriginZ + a_OriginX) / 7) % DoubleSize) - m_Size) / 4;
+		int EndZ = a_OriginZ + (((a_Noise.IntNoise3DInt(a_OriginZ + 17 * a_NumSegments, a_OriginX, a_OriginY) / 7) % DoubleSize) - m_Size) / 2;
+		int EndR = GetRadius(a_Noise, a_OriginX + 7 * i, a_OriginY + 11 * i, a_OriginZ + a_OriginX);
+		m_Tunnels.push_back(new cCaveTunnel(a_OriginX, a_OriginY, a_OriginZ, Radius, EndX, EndY, EndZ, EndR, a_Noise));
+		GenerateTunnelsFromPoint(EndX, EndY, EndZ, a_Noise, i);
+		a_OriginX = EndX;
+		a_OriginY = EndY;
+		a_OriginZ = EndZ;
+		Radius = EndR;
+	}  // for i - a_NumSegments
+}
+
+
+
+
+
+int cStructGenWormNestCaves::cCaveSystem::GetRadius(cNoise & a_Noise, int a_OriginX, int a_OriginY, int a_OriginZ)
+{
+	// Instead of a flat distribution noise function, we need to shape it, so that most caves are smallish and only a few select are large
+	int rnd = a_Noise.IntNoise3DInt(a_OriginX, a_OriginY, a_OriginZ) / 11;
+	/*
+	// Not good enough:
+	// The algorithm of choice: emulate gauss-distribution noise by adding 3 flat noises, then fold it in half using absolute value.
+	// To save on processing, use one random value and extract 3 bytes to be separately added as the gaussian noise
+	int sum = (rnd & 0xff) + ((rnd >> 8) & 0xff) + ((rnd >> 16) & 0xff);
+	// sum is now a gaussian-distribution noise within [0 .. 767], with center at 384.
+	// We want mapping 384 -> 3, 0 -> 19, 768 -> 19, so divide by 24 to get [0 .. 31] with center at 16, then use abs() to fold around the center
+	int res = 3 + abs((sum / 24) - 16);
+	*/
+	
+	// Algorithm of choice: random value in the range of zero to random value - heavily towards zero
+	int res = MIN_RADIUS + (rnd >> 8) % ((rnd % (MAX_RADIUS - MIN_RADIUS)) + 1);
+	return res;
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cStructGenWormNestCaves:
+
+cStructGenWormNestCaves::~cStructGenWormNestCaves()
+{
+	ClearCache();
+}
+
+
+
+
+
+void cStructGenWormNestCaves::ClearCache(void)
+{
+	for (cCaveSystems::const_iterator itr = m_Cache.begin(), end = m_Cache.end(); itr != end; ++itr)
+	{
+		delete *itr;
+	}  // for itr - m_Cache[]
+	m_Cache.clear();
+}
+
+
+
+
+
+void cStructGenWormNestCaves::GenStructures(cChunkDesc & a_ChunkDesc)
+{
+	int ChunkX = a_ChunkDesc.GetChunkX();
+	int ChunkZ = a_ChunkDesc.GetChunkZ();
+	cCaveSystems Caves;
+	GetCavesForChunk(ChunkX, ChunkZ, Caves);
+	for (cCaveSystems::const_iterator itr = Caves.begin(); itr != Caves.end(); ++itr)
+	{
+		(*itr)->ProcessChunk(ChunkX, ChunkZ, a_ChunkDesc.GetBlockTypes(), a_ChunkDesc.GetHeightMap());
+	}  // for itr - Caves[]
+}
+
+
+
+
+
+void cStructGenWormNestCaves::GetCavesForChunk(int a_ChunkX, int a_ChunkZ, cStructGenWormNestCaves::cCaveSystems & a_Caves)
+{
+	int BaseX = a_ChunkX * cChunkDef::Width / m_Grid;
+	int BaseZ = a_ChunkZ * cChunkDef::Width / m_Grid;
+	if (BaseX < 0)
+	{
+		--BaseX;
+	}
+	if (BaseZ < 0)
+	{
+		--BaseZ;
+	}
+	BaseX -= NEIGHBORHOOD_SIZE / 2;
+	BaseZ -= NEIGHBORHOOD_SIZE / 2;
+
+	// Walk the cache, move each cave system that we want into a_Caves:
+	int StartX = BaseX * m_Grid;
+	int EndX = (BaseX + NEIGHBORHOOD_SIZE + 1) * m_Grid;
+	int StartZ = BaseZ * m_Grid;
+	int EndZ = (BaseZ + NEIGHBORHOOD_SIZE + 1) * m_Grid;
+	for (cCaveSystems::iterator itr = m_Cache.begin(), end = m_Cache.end(); itr != end;)
+	{
+		if (
+			((*itr)->m_BlockX >= StartX) && ((*itr)->m_BlockX < EndX) &&
+			((*itr)->m_BlockZ >= StartZ) && ((*itr)->m_BlockZ < EndZ)
+		)
+		{
+			// want
+			a_Caves.push_back(*itr);
+			itr = m_Cache.erase(itr);
+		}
+		else
+		{
+			// don't want
+			++itr;
+		}
+	}  // for itr - m_Cache[]
+	
+	for (int x = 0; x < NEIGHBORHOOD_SIZE; x++)
+	{
+		int RealX = (BaseX + x) * m_Grid;
+		for (int z = 0; z < NEIGHBORHOOD_SIZE; z++)
+		{
+			int RealZ = (BaseZ + z) * m_Grid;
+			bool Found = false;
+			for (cCaveSystems::const_iterator itr = a_Caves.begin(), end = a_Caves.end(); itr != end; ++itr)
+			{
+				if (((*itr)->m_BlockX == RealX) && ((*itr)->m_BlockZ == RealZ))
+				{
+					Found = true;
+					break;
+				}
+			}
+			if (!Found)
+			{
+				a_Caves.push_back(new cCaveSystem(RealX, RealZ, m_MaxOffset, m_Size, m_Noise));
+			}
+		}
+	}
+	
+	// Copy a_Caves into m_Cache to the beginning:
+	cCaveSystems CavesCopy(a_Caves);
+	m_Cache.splice(m_Cache.begin(), CavesCopy, CavesCopy.begin(), CavesCopy.end());
+	
+	// Trim the cache if it's too long:
+	if (m_Cache.size() > 100)
+	{
+		cCaveSystems::iterator itr = m_Cache.begin();
+		std::advance(itr, 100);
+		for (cCaveSystems::iterator end = m_Cache.end(); itr != end; ++itr)
+		{
+			delete *itr;
+		}
+		itr = m_Cache.begin();
+		std::advance(itr, 100);
+		m_Cache.erase(itr, m_Cache.end());
+	}
+	
+	/*
+	// Uncomment this block for debugging the caves' shapes in 2D using an SVG export
+	#ifdef _DEBUG
+	AString SVG;
+	SVG.append("<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>\n<svg xmlns=\"http://www.w3.org/2000/svg\" width=\"1024\" height = \"1024\">\n");
+	SVG.reserve(2 * 1024 * 1024);
+	for (cCaveSystems::const_iterator itr = a_Caves.begin(), end = a_Caves.end(); itr != end; ++itr)
+	{
+		int Color = 0x10 * abs((*itr)->m_BlockX / m_Grid);
+		Color |= 0x1000 * abs((*itr)->m_BlockZ / m_Grid);
+		SVG.append((*itr)->ExportAsSVG(Color, 512, 512));
+	}
+	SVG.append("</svg>\n");
+	
+	AString fnam;
+	Printf(fnam, "wnc\\%03d_%03d.svg", a_ChunkX, a_ChunkZ);
+	cFile File(fnam, cFile::fmWrite);
+	File.Write(SVG.c_str(), SVG.size());
+	#endif  // _DEBUG
+	//*/
+}
+
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cStructGenMarbleCaves:
+
+static float GetMarbleNoise( float x, float y, float z, cNoise & a_Noise )
+{
+	static const float PI_2 = 1.57079633f;
+	float oct1 = (a_Noise.CubicNoise3D(x * 0.1f, y * 0.1f, z * 0.1f )) * 4;
+
+	oct1 = oct1 * oct1 * oct1;
+	if (oct1 < 0.f)  oct1 = PI_2;
+	if (oct1 > PI_2) oct1 = PI_2;
+
+	return oct1;
+}
+
+
+
+
+
+void cStructGenMarbleCaves::GenStructures(cChunkDesc & a_ChunkDesc)
+{
+	cNoise Noise(m_Seed);
+	for (int z = 0; z < cChunkDef::Width; z++) 
+	{
+		const float zz = (float)(a_ChunkDesc.GetChunkZ() * cChunkDef::Width + z);
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			const float xx = (float)(a_ChunkDesc.GetChunkX() * cChunkDef::Width + x);
+			
+			int Top = a_ChunkDesc.GetHeight(x, z);
+			for (int y = 1; y < Top; ++y )
+			{
+				if (a_ChunkDesc.GetBlockType(x, y, z) != E_BLOCK_STONE)
+				{
+					continue;
+				}
+
+				const float yy = (float)y;
+				const float WaveNoise = 1;
+				if (cosf(GetMarbleNoise(xx, yy * 0.5f, zz, Noise)) * fabs(cosf(yy * 0.2f + WaveNoise * 2) * 0.75f + WaveNoise) > 0.0005f)
+				{
+					a_ChunkDesc.SetBlockType(x, y, z, E_BLOCK_AIR);
+				}
+			}  // for y
+		}  // for x
+	}  // for z
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cStructGenDualRidgeCaves:
+
+void cStructGenDualRidgeCaves::GenStructures(cChunkDesc & a_ChunkDesc)
+{
+	for (int z = 0; z < cChunkDef::Width; z++) 
+	{
+		const float zz = (float)(a_ChunkDesc.GetChunkZ() * cChunkDef::Width + z) / 10;
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			const float xx = (float)(a_ChunkDesc.GetChunkX() * cChunkDef::Width + x) / 10;
+			
+			int Top = a_ChunkDesc.GetHeight(x, z);
+			for (int y = 1; y <= Top; ++y)
+			{
+				const float yy = (float)y / 10;
+				const float WaveNoise = 1;
+				float n1 = m_Noise1.CubicNoise3D(xx, yy, zz);
+				float n2 = m_Noise2.CubicNoise3D(xx, yy, zz);
+				float n3 = m_Noise1.CubicNoise3D(xx * 4, yy * 4, zz * 4) / 4;
+				float n4 = m_Noise2.CubicNoise3D(xx * 4, yy * 4, zz * 4) / 4;
+				if ((abs(n1 + n3) * abs(n2 + n4)) > m_Threshold)
+				{
+					a_ChunkDesc.SetBlockType(x, y, z, E_BLOCK_AIR);
+				}
+			}  // for y
+		}  // for x
+	}  // for z
+}
+
+
+
+

src/Generating/Caves.h

@@ -0,0 +1,102 @@
+
+// Caves.h
+
+// Interfaces to the various cave structure generators:
+//   - cStructGenWormNestCaves
+//   - cStructGenMarbleCaves
+//   - cStructGenNetherCaves
+
+
+
+
+
+#pragma once
+
+#include "ComposableGenerator.h"
+#include "../Noise.h"
+
+
+
+
+
+class cStructGenMarbleCaves :
+	public cStructureGen
+{
+public:
+	cStructGenMarbleCaves(int a_Seed) : m_Seed(a_Seed) {}
+	
+protected:
+
+	int m_Seed;
+	
+	// cStructureGen override:
+	virtual void GenStructures(cChunkDesc & a_ChunkDesc) override;
+} ;
+
+
+
+
+
+class cStructGenDualRidgeCaves :
+	public cStructureGen
+{
+public:
+	cStructGenDualRidgeCaves(int a_Seed, float a_Threshold) :
+		m_Noise1(a_Seed),
+		m_Noise2(2 * a_Seed + 19999),
+		m_Seed(a_Seed),
+		m_Threshold(a_Threshold)
+	{
+	}
+	
+protected:
+	cNoise m_Noise1;
+	cNoise m_Noise2;
+	int    m_Seed;
+	float  m_Threshold;
+	
+	// cStructureGen override:
+	virtual void GenStructures(cChunkDesc & a_ChunkDesc) override;
+} ;
+
+
+
+
+
+class cStructGenWormNestCaves :
+	public cStructureGen
+{
+public:
+	cStructGenWormNestCaves(int a_Seed, int a_Size = 64, int a_Grid = 96, int a_MaxOffset = 128) :
+		m_Noise(a_Seed),
+		m_Size(a_Size),
+		m_Grid(a_Grid),
+		m_MaxOffset(a_MaxOffset)
+	{
+	}
+	
+	~cStructGenWormNestCaves();
+	
+protected:
+	class cCaveSystem;  // fwd: Caves.cpp
+	typedef std::list<cCaveSystem *> cCaveSystems;
+
+	cNoise       m_Noise;
+	int          m_Size;  // relative size of the cave systems' caves. Average number of blocks of each initial tunnel
+	int          m_MaxOffset;  // maximum offset of the cave nest origin from the grid cell the nest belongs to
+	int          m_Grid;  // average spacing of the nests
+	cCaveSystems m_Cache;
+	
+	/// Clears everything from the cache
+	void ClearCache(void);
+	
+	/// Returns all caves that *may* intersect the given chunk. All the caves are valid until the next call to this function.
+	void GetCavesForChunk(int a_ChunkX, int a_ChunkZ, cCaveSystems & a_Caves);
+	
+	// cStructGen override:
+	virtual void GenStructures(cChunkDesc & a_ChunkDesc) override;
+} ;
+
+
+
+

src/Generating/ChunkDesc.cpp

@@ -0,0 +1,605 @@
+
+// ChunkDesc.cpp
+
+// Implements the cChunkDesc class representing the chunk description used while generating a chunk. This class is also exported to Lua for HOOK_CHUNK_GENERATING.
+
+#include "Globals.h"
+#include "ChunkDesc.h"
+#include "../BlockArea.h"
+#include "../Cuboid.h"
+#include "../Noise.h"
+#include "../BlockEntities/BlockEntity.h"
+
+
+
+
+
+cChunkDesc::cChunkDesc(int a_ChunkX, int a_ChunkZ) :
+	m_ChunkX(a_ChunkX),
+	m_ChunkZ(a_ChunkZ),
+	m_bUseDefaultBiomes(true),
+	m_bUseDefaultHeight(true),
+	m_bUseDefaultComposition(true),
+	m_bUseDefaultStructures(true),
+	m_bUseDefaultFinish(true)
+{
+	m_BlockArea.Create(cChunkDef::Width, cChunkDef::Height, cChunkDef::Width);
+	/*
+	memset(m_BlockTypes, 0, sizeof(cChunkDef::BlockTypes));
+	memset(m_BlockMeta,  0, sizeof(cChunkDef::BlockNibbles));
+	*/
+	memset(m_BiomeMap,   0, sizeof(cChunkDef::BiomeMap));
+	memset(m_HeightMap,  0, sizeof(cChunkDef::HeightMap));
+}
+
+
+
+
+
+cChunkDesc::~cChunkDesc()
+{
+	// Nothing needed yet
+}
+
+
+
+
+
+void cChunkDesc::SetChunkCoords(int a_ChunkX, int a_ChunkZ)
+{
+	m_ChunkX = a_ChunkX;
+	m_ChunkZ = a_ChunkZ;
+}
+
+
+
+
+
+void cChunkDesc::FillBlocks(BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta)
+{
+	m_BlockArea.Fill(cBlockArea::baTypes | cBlockArea::baMetas, a_BlockType, a_BlockMeta);
+}
+
+
+
+
+
+void cChunkDesc::SetBlockTypeMeta(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta)
+{
+	m_BlockArea.SetRelBlockTypeMeta(a_RelX, a_RelY, a_RelZ, a_BlockType, a_BlockMeta);
+}
+
+
+
+
+
+void cChunkDesc::GetBlockTypeMeta(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE & a_BlockType, NIBBLETYPE & a_BlockMeta)
+{
+	m_BlockArea.GetRelBlockTypeMeta(a_RelX, a_RelY, a_RelZ, a_BlockType, a_BlockMeta);
+}
+
+
+
+
+
+void cChunkDesc::SetBlockType(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE a_BlockType)
+{
+	cChunkDef::SetBlock(m_BlockArea.GetBlockTypes(), a_RelX, a_RelY, a_RelZ, a_BlockType);
+}
+
+
+
+
+
+BLOCKTYPE cChunkDesc::GetBlockType(int a_RelX, int a_RelY, int a_RelZ)
+{
+	return cChunkDef::GetBlock(m_BlockArea.GetBlockTypes(), a_RelX, a_RelY, a_RelZ);
+}
+
+
+
+
+
+NIBBLETYPE cChunkDesc::GetBlockMeta(int a_RelX, int a_RelY, int a_RelZ)
+{
+	return m_BlockArea.GetRelBlockMeta(a_RelX, a_RelY, a_RelZ);
+}
+
+
+
+
+
+void cChunkDesc::SetBlockMeta(int a_RelX, int a_RelY, int a_RelZ, NIBBLETYPE a_BlockMeta)
+{
+	m_BlockArea.SetRelBlockMeta(a_RelX, a_RelY, a_RelZ, a_BlockMeta);
+}
+
+
+
+
+
+void cChunkDesc::SetBiome(int a_RelX, int a_RelZ, int a_BiomeID)
+{
+	cChunkDef::SetBiome(m_BiomeMap, a_RelX, a_RelZ, (EMCSBiome)a_BiomeID);
+}
+
+
+
+
+EMCSBiome cChunkDesc::GetBiome(int a_RelX, int a_RelZ)
+{
+	return cChunkDef::GetBiome(m_BiomeMap, a_RelX, a_RelZ);
+}
+
+
+
+
+
+void cChunkDesc::SetHeight(int a_RelX, int a_RelZ, int a_Height)
+{
+	cChunkDef::SetHeight(m_HeightMap, a_RelX, a_RelZ, a_Height);
+}
+
+
+
+
+
+int cChunkDesc::GetHeight(int a_RelX, int a_RelZ)
+{
+	return cChunkDef::GetHeight(m_HeightMap, a_RelX, a_RelZ);
+}
+
+
+
+
+
+void cChunkDesc::SetUseDefaultBiomes(bool a_bUseDefaultBiomes)
+{
+	m_bUseDefaultBiomes = a_bUseDefaultBiomes;
+}
+
+
+
+
+
+bool cChunkDesc::IsUsingDefaultBiomes(void) const
+{
+	return m_bUseDefaultBiomes;
+}
+
+
+
+
+
+void cChunkDesc::SetUseDefaultHeight(bool a_bUseDefaultHeight)
+{
+	m_bUseDefaultHeight = a_bUseDefaultHeight;
+}
+
+
+
+
+
+bool cChunkDesc::IsUsingDefaultHeight(void) const
+{
+	return m_bUseDefaultHeight;
+}
+
+
+
+
+
+void cChunkDesc::SetUseDefaultComposition(bool a_bUseDefaultComposition)
+{
+	m_bUseDefaultComposition = a_bUseDefaultComposition;
+}
+
+
+
+
+
+bool cChunkDesc::IsUsingDefaultComposition(void) const
+{
+	return m_bUseDefaultComposition;
+}
+
+
+
+
+
+void cChunkDesc::SetUseDefaultStructures(bool a_bUseDefaultStructures)
+{
+	m_bUseDefaultStructures = a_bUseDefaultStructures;
+}
+
+
+
+
+
+bool cChunkDesc::IsUsingDefaultStructures(void) const
+{
+	return m_bUseDefaultStructures;
+}
+
+
+
+
+
+void cChunkDesc::SetUseDefaultFinish(bool a_bUseDefaultFinish)
+{
+	m_bUseDefaultFinish = a_bUseDefaultFinish;
+}
+
+
+
+
+
+bool cChunkDesc::IsUsingDefaultFinish(void) const
+{
+	return m_bUseDefaultFinish;
+}
+
+
+
+
+void cChunkDesc::WriteBlockArea(const cBlockArea & a_BlockArea, int a_RelX, int a_RelY, int a_RelZ, cBlockArea::eMergeStrategy a_MergeStrategy)
+{
+	m_BlockArea.Merge(a_BlockArea, a_RelX, a_RelY, a_RelZ, a_MergeStrategy);
+}
+
+
+
+
+
+void cChunkDesc::ReadBlockArea(cBlockArea & a_Dest, int a_MinRelX, int a_MaxRelX, int a_MinRelY, int a_MaxRelY, int a_MinRelZ, int a_MaxRelZ)
+{
+	// Normalize the coords:
+	if (a_MinRelX > a_MaxRelX)
+	{
+		std::swap(a_MinRelX, a_MaxRelX);
+	}
+	if (a_MinRelY > a_MaxRelY)
+	{
+		std::swap(a_MinRelY, a_MaxRelY);
+	}
+	if (a_MinRelZ > a_MaxRelZ)
+	{
+		std::swap(a_MinRelZ, a_MaxRelZ);
+	}
+
+	// Include the Max coords:
+	a_MaxRelX += 1;
+	a_MaxRelY += 1;
+	a_MaxRelZ += 1;
+	
+	// Check coords validity:
+	if (a_MinRelX < 0)
+	{
+		LOGWARNING("%s: MinRelX less than zero, adjusting to zero", __FUNCTION__);
+		a_MinRelX = 0;
+	}
+	else if (a_MinRelX >= cChunkDef::Width)
+	{
+		LOGWARNING("%s: MinRelX more than chunk width, adjusting to chunk width", __FUNCTION__);
+		a_MinRelX = cChunkDef::Width - 1;
+	}
+	if (a_MaxRelX < 0)
+	{
+		LOGWARNING("%s: MaxRelX less than zero, adjusting to zero", __FUNCTION__);
+		a_MaxRelX = 0;
+	}
+	else if (a_MinRelX >= cChunkDef::Width)
+	{
+		LOGWARNING("%s: MaxRelX more than chunk width, adjusting to chunk width", __FUNCTION__);
+		a_MaxRelX = cChunkDef::Width - 1;
+	}
+
+	if (a_MinRelY < 0)
+	{
+		LOGWARNING("%s: MinRelY less than zero, adjusting to zero", __FUNCTION__);
+		a_MinRelY = 0;
+	}
+	else if (a_MinRelY >= cChunkDef::Height)
+	{
+		LOGWARNING("%s: MinRelY more than chunk height, adjusting to chunk height", __FUNCTION__);
+		a_MinRelY = cChunkDef::Height - 1;
+	}
+	if (a_MaxRelY < 0)
+	{
+		LOGWARNING("%s: MaxRelY less than zero, adjusting to zero", __FUNCTION__);
+		a_MaxRelY = 0;
+	}
+	else if (a_MinRelY >= cChunkDef::Height)
+	{
+		LOGWARNING("%s: MaxRelY more than chunk height, adjusting to chunk height", __FUNCTION__);
+		a_MaxRelY = cChunkDef::Height - 1;
+	}
+	
+	if (a_MinRelZ < 0)
+	{
+		LOGWARNING("%s: MinRelZ less than zero, adjusting to zero", __FUNCTION__);
+		a_MinRelZ = 0;
+	}
+	else if (a_MinRelZ >= cChunkDef::Width)
+	{
+		LOGWARNING("%s: MinRelZ more than chunk width, adjusting to chunk width", __FUNCTION__);
+		a_MinRelZ = cChunkDef::Width - 1;
+	}
+	if (a_MaxRelZ < 0)
+	{
+		LOGWARNING("%s: MaxRelZ less than zero, adjusting to zero", __FUNCTION__);
+		a_MaxRelZ = 0;
+	}
+	else if (a_MinRelZ >= cChunkDef::Width)
+	{
+		LOGWARNING("%s: MaxRelZ more than chunk width, adjusting to chunk width", __FUNCTION__);
+		a_MaxRelZ = cChunkDef::Width - 1;
+	}
+
+	// Prepare the block area:
+	int SizeX = a_MaxRelX - a_MinRelX;
+	int SizeY = a_MaxRelY - a_MinRelY;
+	int SizeZ = a_MaxRelZ - a_MinRelZ;
+	a_Dest.Clear();
+	a_Dest.m_OriginX = m_ChunkX * cChunkDef::Width + a_MinRelX;
+	a_Dest.m_OriginY = a_MinRelY;
+	a_Dest.m_OriginZ = m_ChunkZ * cChunkDef::Width + a_MinRelZ;
+	a_Dest.SetSize(SizeX, SizeY, SizeZ, cBlockArea::baTypes | cBlockArea::baMetas);
+
+	for (int y = 0; y < SizeY; y++)
+	{
+		int CDY = a_MinRelY + y;
+		for (int z = 0; z < SizeZ; z++)
+		{
+			int CDZ = a_MinRelZ + z;
+			for (int x = 0; x < SizeX; x++)
+			{
+				int CDX = a_MinRelX + x;
+				BLOCKTYPE BlockType;
+				NIBBLETYPE BlockMeta;
+				GetBlockTypeMeta(CDX, CDY, CDZ, BlockType, BlockMeta);
+				a_Dest.SetRelBlockTypeMeta(x, y, z, BlockType, BlockMeta);
+			}  // for x
+		}  // for z
+	}  // for y
+}
+
+
+
+
+
+HEIGHTTYPE cChunkDesc::GetMaxHeight(void) const
+{
+	HEIGHTTYPE MaxHeight = m_HeightMap[0];
+	for (int i = 1; i < ARRAYCOUNT(m_HeightMap); i++)
+	{
+		if (m_HeightMap[i] > MaxHeight)
+		{
+			MaxHeight = m_HeightMap[i];
+		}
+	}
+	return MaxHeight;
+}
+
+
+
+
+
+void cChunkDesc::FillRelCuboid(
+	int a_MinX, int a_MaxX,
+	int a_MinY, int a_MaxY,
+	int a_MinZ, int a_MaxZ,
+	BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta
+)
+{
+	int MinX = std::max(a_MinX, 0);
+	int MinY = std::max(a_MinY, 0);
+	int MinZ = std::max(a_MinZ, 0);
+	int MaxX = std::min(a_MaxX, cChunkDef::Width - 1);
+	int MaxY = std::min(a_MaxY, cChunkDef::Height - 1);
+	int MaxZ = std::min(a_MaxZ, cChunkDef::Width - 1);
+	
+	for (int y = MinY; y <= MaxY; y++)
+	{
+		for (int z = MinZ; z <= MaxZ; z++)
+		{
+			for (int x = MinX; x <= MaxX; x++)
+			{
+				SetBlockTypeMeta(x, y, z, a_BlockType, a_BlockMeta);
+			}
+		}  // for z
+	}  // for y
+}
+
+
+
+
+
+void cChunkDesc::ReplaceRelCuboid(
+	int a_MinX, int a_MaxX,
+	int a_MinY, int a_MaxY,
+	int a_MinZ, int a_MaxZ,
+	BLOCKTYPE a_SrcType, NIBBLETYPE a_SrcMeta,
+	BLOCKTYPE a_DstType, NIBBLETYPE a_DstMeta
+)
+{
+	int MinX = std::max(a_MinX, 0);
+	int MinY = std::max(a_MinY, 0);
+	int MinZ = std::max(a_MinZ, 0);
+	int MaxX = std::min(a_MaxX, cChunkDef::Width - 1);
+	int MaxY = std::min(a_MaxY, cChunkDef::Height - 1);
+	int MaxZ = std::min(a_MaxZ, cChunkDef::Width - 1);
+	
+	for (int y = MinY; y <= MaxY; y++)
+	{
+		for (int z = MinZ; z <= MaxZ; z++)
+		{
+			for (int x = MinX; x <= MaxX; x++)
+			{
+				BLOCKTYPE BlockType;
+				NIBBLETYPE BlockMeta;
+				GetBlockTypeMeta(x, y, z, BlockType, BlockMeta);
+				if ((BlockType == a_SrcType) && (BlockMeta == a_SrcMeta))
+				{
+					SetBlockTypeMeta(x, y, z, a_DstType, a_DstMeta);
+				}
+			}
+		}  // for z
+	}  // for y
+}
+
+
+
+
+
+void cChunkDesc::FloorRelCuboid(
+	int a_MinX, int a_MaxX,
+	int a_MinY, int a_MaxY,
+	int a_MinZ, int a_MaxZ,
+	BLOCKTYPE a_DstType, NIBBLETYPE a_DstMeta
+)
+{
+	int MinX = std::max(a_MinX, 0);
+	int MinY = std::max(a_MinY, 0);
+	int MinZ = std::max(a_MinZ, 0);
+	int MaxX = std::min(a_MaxX, cChunkDef::Width - 1);
+	int MaxY = std::min(a_MaxY, cChunkDef::Height - 1);
+	int MaxZ = std::min(a_MaxZ, cChunkDef::Width - 1);
+	
+	for (int y = MinY; y <= MaxY; y++)
+	{
+		for (int z = MinZ; z <= MaxZ; z++)
+		{
+			for (int x = MinX; x <= MaxX; x++)
+			{
+				switch (GetBlockType(x, y, z))
+				{
+					case E_BLOCK_AIR:
+					case E_BLOCK_WATER:
+					case E_BLOCK_STATIONARY_WATER:
+					{
+						SetBlockTypeMeta(x, y, z, a_DstType, a_DstMeta);
+						break;
+					}
+				}  // switch (GetBlockType)
+			}  // for x
+		}  // for z
+	}  // for y
+}
+
+
+
+
+
+void cChunkDesc::RandomFillRelCuboid(
+	int a_MinX, int a_MaxX,
+	int a_MinY, int a_MaxY,
+	int a_MinZ, int a_MaxZ,
+	BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta,
+	int a_RandomSeed, int a_ChanceOutOf10k
+)
+{
+	cNoise Noise(a_RandomSeed);
+	int MinX = std::max(a_MinX, 0);
+	int MinY = std::max(a_MinY, 0);
+	int MinZ = std::max(a_MinZ, 0);
+	int MaxX = std::min(a_MaxX, cChunkDef::Width - 1);
+	int MaxY = std::min(a_MaxY, cChunkDef::Height - 1);
+	int MaxZ = std::min(a_MaxZ, cChunkDef::Width - 1);
+	
+	for (int y = MinY; y <= MaxY; y++)
+	{
+		for (int z = MinZ; z <= MaxZ; z++)
+		{
+			for (int x = MinX; x <= MaxX; x++)
+			{
+				int rnd = (Noise.IntNoise3DInt(x, y, z) / 7) % 10000;
+				if (rnd <= a_ChanceOutOf10k)
+				{
+					SetBlockTypeMeta(x, y, z, a_BlockType, a_BlockMeta);
+				}
+			}
+		}  // for z
+	}  // for y
+}
+
+
+
+
+
+cBlockEntity * cChunkDesc::GetBlockEntity(int a_RelX, int a_RelY, int a_RelZ)
+{
+	int AbsX = a_RelX + m_ChunkX * cChunkDef::Width;
+	int AbsZ = a_RelZ + m_ChunkZ * cChunkDef::Width;
+	for (cBlockEntityList::iterator itr = m_BlockEntities.begin(), end = m_BlockEntities.end(); itr != end; ++itr)
+	{
+		if (((*itr)->GetPosX() == AbsX) && ((*itr)->GetPosY() == a_RelY) && ((*itr)->GetPosZ() == AbsZ))
+		{
+			// Already in the list:
+			if ((*itr)->GetBlockType() != GetBlockType(a_RelX, a_RelY, a_RelZ))
+			{
+				// Wrong type, the block type has been overwritten. Erase and create new:
+				m_BlockEntities.erase(itr);
+				break;
+			}
+			// Correct type, already present. Return it:
+			return *itr;
+		}
+	}  // for itr - m_BlockEntities[]
+	
+	// The block entity is not created yet, try to create it and add to list:
+	cBlockEntity * be = cBlockEntity::CreateByBlockType(GetBlockType(a_RelX, a_RelY, a_RelZ), GetBlockMeta(a_RelX, a_RelY, a_RelZ), AbsX, a_RelY, AbsZ);
+	if (be == NULL)
+	{
+		// No block entity for this block type
+		return NULL;
+	}
+	m_BlockEntities.push_back(be);
+	return be;
+}
+
+
+
+
+
+void cChunkDesc::CompressBlockMetas(cChunkDef::BlockNibbles & a_DestMetas)
+{
+	const NIBBLETYPE * AreaMetas = m_BlockArea.GetBlockMetas();
+	for (int i = 0; i < ARRAYCOUNT(a_DestMetas); i++)
+	{
+		a_DestMetas[i] = AreaMetas[2 * i] | (AreaMetas[2 * i + 1] << 4);
+	}
+}
+
+
+
+
+
+#ifdef _DEBUG
+
+void cChunkDesc::VerifyHeightmap(void)
+{
+	for (int x = 0; x < cChunkDef::Width; x++)
+	{
+		for (int z = 0; z < cChunkDef::Width; z++)
+		{
+			for (int y = cChunkDef::Height - 1; y > 0; y--)
+			{
+				BLOCKTYPE BlockType = GetBlockType(x, y, z);
+				if (BlockType != E_BLOCK_AIR)
+				{
+					int Height = GetHeight(x, z);
+					ASSERT(Height == y);
+					break;
+				}
+			}  // for y
+		}  // for z
+	}  // for x
+}
+
+#endif  // _DEBUG
+
+
+
+
+

src/Generating/ChunkDesc.h

@@ -0,0 +1,217 @@
+
+// ChunkDesc.h
+
+// Declares the cChunkDesc class representing the chunk description used while generating a chunk. This class is also exported to Lua for HOOK_CHUNK_GENERATING.
+
+
+
+
+
+#pragma once
+
+#include "../BlockArea.h"
+#include "../ChunkDef.h"
+#include "../Cuboid.h"
+
+
+
+
+
+// fwd: ../BlockArea.h
+class cBlockArea;
+
+
+
+
+
+// tolua_begin
+class cChunkDesc
+{
+public:
+	// tolua_end
+	
+	/// Uncompressed block metas, 1 meta per byte
+	typedef NIBBLETYPE BlockNibbleBytes[cChunkDef::NumBlocks];
+	
+	cChunkDesc(int a_ChunkX, int a_ChunkZ);
+	~cChunkDesc();
+
+	void SetChunkCoords(int a_ChunkX, int a_ChunkZ);
+	
+	// tolua_begin
+
+	int GetChunkX(void) const { return m_ChunkX; }
+	int GetChunkZ(void) const { return m_ChunkZ; }
+	
+	void       FillBlocks(BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta);
+	void       SetBlockTypeMeta(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta);
+	void       GetBlockTypeMeta(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE & a_BlockType, NIBBLETYPE & a_BlockMeta);
+
+	void       SetBlockType(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE a_BlockType);
+	BLOCKTYPE  GetBlockType(int a_RelX, int a_RelY, int a_RelZ);
+	
+	void       SetBlockMeta(int a_RelX, int a_RelY, int a_RelZ, NIBBLETYPE a_BlockMeta);
+	NIBBLETYPE GetBlockMeta(int a_RelX, int a_RelY, int a_RelZ);
+
+	void       SetBiome(int a_RelX, int a_RelZ, int a_BiomeID);
+	EMCSBiome  GetBiome(int a_RelX, int a_RelZ);
+
+	void       SetHeight(int a_RelX, int a_RelZ, int a_Height);
+	int        GetHeight(int a_RelX, int a_RelZ);
+
+	// Default generation:
+	void SetUseDefaultBiomes(bool a_bUseDefaultBiomes);
+	bool IsUsingDefaultBiomes(void) const;
+	void SetUseDefaultHeight(bool a_bUseDefaultHeight);
+	bool IsUsingDefaultHeight(void) const;
+	void SetUseDefaultComposition(bool a_bUseDefaultComposition);
+	bool IsUsingDefaultComposition(void) const;
+	void SetUseDefaultStructures(bool a_bUseDefaultStructures);
+	bool IsUsingDefaultStructures(void) const;
+	void SetUseDefaultFinish(bool a_bUseDefaultFinish);
+	bool IsUsingDefaultFinish(void) const;
+
+	/// Writes the block area into the chunk, with its origin set at the specified relative coords. Area's data overwrite everything in the chunk.
+	void WriteBlockArea(const cBlockArea & a_BlockArea, int a_RelX, int a_RelY, int a_RelZ, cBlockArea::eMergeStrategy a_MergeStrategy = cBlockArea::msOverwrite);
+
+	/// Reads an area from the chunk into a cBlockArea, blocktypes and blockmetas
+	void ReadBlockArea(cBlockArea & a_Dest, int a_MinRelX, int a_MaxRelX, int a_MinRelY, int a_MaxRelY, int a_MinRelZ, int a_MaxRelZ);
+
+	/// Returns the maximum height value in the heightmap
+	HEIGHTTYPE GetMaxHeight(void) const;
+	
+	/// Fills the relative cuboid with specified block; allows cuboid out of range of this chunk
+	void FillRelCuboid(
+		int a_MinX, int a_MaxX,
+		int a_MinY, int a_MaxY,
+		int a_MinZ, int a_MaxZ,
+		BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta
+	);
+	
+	/// Fills the relative cuboid with specified block; allows cuboid out of range of this chunk
+	void FillRelCuboid(const cCuboid & a_RelCuboid, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta)
+	{
+		FillRelCuboid(
+			a_RelCuboid.p1.x, a_RelCuboid.p2.x,
+			a_RelCuboid.p1.y, a_RelCuboid.p2.y,
+			a_RelCuboid.p1.z, a_RelCuboid.p2.z,
+			a_BlockType, a_BlockMeta
+		);
+	}
+	
+	/// Replaces the specified src blocks in the cuboid by the dst blocks; allows cuboid out of range of this chunk
+	void ReplaceRelCuboid(
+		int a_MinX, int a_MaxX,
+		int a_MinY, int a_MaxY,
+		int a_MinZ, int a_MaxZ,
+		BLOCKTYPE a_SrcType, NIBBLETYPE a_SrcMeta,
+		BLOCKTYPE a_DstType, NIBBLETYPE a_DstMeta
+	);
+	
+	/// Replaces the specified src blocks in the cuboid by the dst blocks; allows cuboid out of range of this chunk
+	void ReplaceRelCuboid(
+		const cCuboid & a_RelCuboid,
+		BLOCKTYPE a_SrcType, NIBBLETYPE a_SrcMeta,
+		BLOCKTYPE a_DstType, NIBBLETYPE a_DstMeta
+	)
+	{
+		ReplaceRelCuboid(
+			a_RelCuboid.p1.x, a_RelCuboid.p2.x,
+			a_RelCuboid.p1.y, a_RelCuboid.p2.y,
+			a_RelCuboid.p1.z, a_RelCuboid.p2.z,
+			a_SrcType, a_SrcMeta,
+			a_DstType, a_DstMeta
+		);
+	}
+
+	/// Replaces the blocks in the cuboid by the dst blocks if they are considered non-floor (air, water); allows cuboid out of range of this chunk
+	void FloorRelCuboid(
+		int a_MinX, int a_MaxX,
+		int a_MinY, int a_MaxY,
+		int a_MinZ, int a_MaxZ,
+		BLOCKTYPE a_DstType, NIBBLETYPE a_DstMeta
+	);
+	
+	/// Replaces the blocks in the cuboid by the dst blocks if they are considered non-floor (air, water); allows cuboid out of range of this chunk
+	void FloorRelCuboid(
+		const cCuboid & a_RelCuboid,
+		BLOCKTYPE a_DstType, NIBBLETYPE a_DstMeta
+	)
+	{
+		FloorRelCuboid(
+			a_RelCuboid.p1.x, a_RelCuboid.p2.x,
+			a_RelCuboid.p1.y, a_RelCuboid.p2.y,
+			a_RelCuboid.p1.z, a_RelCuboid.p2.z,
+			a_DstType, a_DstMeta
+		);
+	}
+	
+	/// Fills the relative cuboid with specified block with a random chance; allows cuboid out of range of this chunk
+	void RandomFillRelCuboid(
+		int a_MinX, int a_MaxX,
+		int a_MinY, int a_MaxY,
+		int a_MinZ, int a_MaxZ,
+		BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta,
+		int a_RandomSeed, int a_ChanceOutOf10k
+	);
+	
+	/// Fills the relative cuboid with specified block with a random chance; allows cuboid out of range of this chunk
+	void RandomFillRelCuboid(
+		const cCuboid & a_RelCuboid, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta,
+		int a_RandomSeed, int a_ChanceOutOf10k
+	)
+	{
+		RandomFillRelCuboid(
+			a_RelCuboid.p1.x, a_RelCuboid.p2.x,
+			a_RelCuboid.p1.y, a_RelCuboid.p2.y,
+			a_RelCuboid.p1.z, a_RelCuboid.p2.z,
+			a_BlockType, a_BlockMeta,
+			a_RandomSeed, a_ChanceOutOf10k
+		);
+	}
+	
+	/// Returns the block entity at the specified coords.
+	/// If there is no block entity at those coords, tries to create one, based on the block type
+	/// If the blocktype doesn't support a block entity, returns NULL.
+	cBlockEntity * GetBlockEntity(int a_RelX, int a_RelY, int a_RelZ);
+	
+	// tolua_end
+	
+	// Accessors used by cChunkGenerator::Generator descendants:
+	inline cChunkDef::BiomeMap &     GetBiomeMap              (void) { return m_BiomeMap; }
+	inline cChunkDef::BlockTypes &   GetBlockTypes            (void) { return *((cChunkDef::BlockTypes *)m_BlockArea.GetBlockTypes()); }
+	// CANNOT, different compression! 
+	// inline cChunkDef::BlockNibbles & GetBlockMetas            (void) { return *((cChunkDef::BlockNibbles *)m_BlockArea.GetBlockMetas()); }
+	inline BlockNibbleBytes &        GetBlockMetasUncompressed(void) { return *((BlockNibbleBytes *)m_BlockArea.GetBlockMetas()); }
+	inline cChunkDef::HeightMap &    GetHeightMap             (void) { return m_HeightMap; }
+	inline cEntityList &             GetEntities              (void) { return m_Entities; }
+	inline cBlockEntityList &        GetBlockEntities         (void) { return m_BlockEntities; }
+	
+	/// Compresses the metas from the BlockArea format (1 meta per byte) into regular format (2 metas per byte)
+	void CompressBlockMetas(cChunkDef::BlockNibbles & a_DestMetas);
+	
+	#ifdef _DEBUG
+	/// Verifies that the heightmap corresponds to blocktype contents; if not, asserts on that column
+	void VerifyHeightmap(void);
+	#endif  // _DEBUG
+	
+private:
+	int m_ChunkX;
+	int m_ChunkZ;
+	
+	cChunkDef::BiomeMap     m_BiomeMap;
+	cBlockArea              m_BlockArea;
+	cChunkDef::HeightMap    m_HeightMap;
+	cEntityList             m_Entities;       // Individual entities are NOT owned by this object!
+	cBlockEntityList        m_BlockEntities;  // Individual block entities are NOT owned by this object!
+
+	bool m_bUseDefaultBiomes;
+	bool m_bUseDefaultHeight;
+	bool m_bUseDefaultComposition;
+	bool m_bUseDefaultStructures;
+	bool m_bUseDefaultFinish;
+} ;  // tolua_export
+
+
+
+

src/Generating/ChunkGenerator.cpp

@@ -0,0 +1,329 @@
+
+#include "Globals.h"
+
+#include "ChunkGenerator.h"
+#include "../World.h"
+#include "../../iniFile/iniFile.h"
+#include "../Root.h"
+#include "../PluginManager.h"
+#include "ChunkDesc.h"
+#include "ComposableGenerator.h"
+#include "Noise3DGenerator.h"
+
+
+
+
+
+/// If the generation queue size exceeds this number, a warning will be output
+const int QUEUE_WARNING_LIMIT = 1000;
+
+/// If the generation queue size exceeds this number, chunks with no clients will be skipped
+const int QUEUE_SKIP_LIMIT = 500;
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cChunkGenerator:
+
+cChunkGenerator::cChunkGenerator(void) :
+	super("cChunkGenerator"),
+	m_World(NULL),
+	m_Generator(NULL)
+{
+}
+
+
+
+
+
+cChunkGenerator::~cChunkGenerator()
+{
+	Stop();
+}
+
+
+
+
+
+bool cChunkGenerator::Start(cWorld * a_World, cIniFile & a_IniFile)
+{
+	MTRand rnd;
+	m_World = a_World;
+	m_Seed = a_IniFile.GetValueSetI("Seed", "Seed", rnd.randInt());
+	AString GeneratorName = a_IniFile.GetValueSet("Generator", "Generator", "Composable");
+	
+	if (NoCaseCompare(GeneratorName, "Noise3D") == 0)
+	{
+		m_Generator = new cNoise3DGenerator(*this);
+	}
+	else
+	{
+		if (NoCaseCompare(GeneratorName, "composable") != 0)
+		{
+			LOGWARN("[Generator]::Generator value \"%s\" not recognized, using \"Composable\".", GeneratorName.c_str());
+		}
+		m_Generator = new cComposableGenerator(*this);
+	}
+
+	if (m_Generator == NULL)
+	{
+		LOGERROR("Generator could not start, aborting the server");
+		return false;
+	}
+	
+	m_Generator->Initialize(a_World, a_IniFile);
+	
+	return super::Start();
+}
+
+
+
+
+
+void cChunkGenerator::Stop(void)
+{
+	m_ShouldTerminate = true;
+	m_Event.Set();
+	m_evtRemoved.Set();  // Wake up anybody waiting for empty queue
+	Wait();
+
+	delete m_Generator;
+	m_Generator = NULL;
+}
+
+
+
+
+
+void cChunkGenerator::QueueGenerateChunk(int a_ChunkX, int a_ChunkY, int a_ChunkZ)
+{
+	{
+		cCSLock Lock(m_CS);
+		
+		// Check if it is already in the queue:
+		for (cChunkCoordsList::iterator itr = m_Queue.begin(); itr != m_Queue.end(); ++itr)
+		{
+			if ((itr->m_ChunkX == a_ChunkX) && (itr->m_ChunkY == a_ChunkY) && (itr->m_ChunkZ == a_ChunkZ))
+			{
+				// Already in the queue, bail out
+				return;
+			}
+		}  // for itr - m_Queue[]
+		
+		// Add to queue, issue a warning if too many:
+		if (m_Queue.size() >= QUEUE_WARNING_LIMIT)
+		{
+			LOGWARN("WARNING: Adding chunk [%i, %i] to generation queue; Queue is too big! (%i)", a_ChunkX, a_ChunkZ, m_Queue.size());
+		}
+		m_Queue.push_back(cChunkCoords(a_ChunkX, a_ChunkY, a_ChunkZ));
+	}
+	
+	m_Event.Set();
+}
+
+
+
+
+
+void cChunkGenerator::GenerateBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap)
+{
+	if (m_Generator != NULL)
+	{
+		m_Generator->GenerateBiomes(a_ChunkX, a_ChunkZ, a_BiomeMap);
+	}
+}
+
+
+
+
+
+void cChunkGenerator::WaitForQueueEmpty(void)
+{
+	cCSLock Lock(m_CS);
+	while (!m_ShouldTerminate && !m_Queue.empty())
+	{
+		cCSUnlock Unlock(Lock);
+		m_evtRemoved.Wait();
+	}
+}
+
+
+
+
+
+int cChunkGenerator::GetQueueLength(void)
+{
+	cCSLock Lock(m_CS);
+	return (int)m_Queue.size();
+}
+
+
+
+
+
+EMCSBiome cChunkGenerator::GetBiomeAt(int a_BlockX, int a_BlockZ)
+{
+	ASSERT(m_Generator != NULL);
+	return m_Generator->GetBiomeAt(a_BlockX, a_BlockZ);
+}
+
+
+
+
+
+BLOCKTYPE cChunkGenerator::GetIniBlock(cIniFile & a_IniFile, const AString & a_SectionName, const AString & a_ValueName, const AString & a_Default)
+{
+	AString BlockType = a_IniFile.GetValueSet(a_SectionName, a_ValueName, a_Default);
+	BLOCKTYPE Block = BlockStringToType(BlockType);
+	if (Block < 0)
+	{
+		LOGWARN("[&s].%s Could not parse block value \"%s\". Using default: \"%s\".", a_SectionName.c_str(), a_ValueName.c_str(), BlockType.c_str(),a_Default.c_str());
+		return BlockStringToType(a_Default);
+	}
+	return Block;
+}
+
+
+
+
+
+void cChunkGenerator::Execute(void)
+{
+	// To be able to display performance information, the generator counts the chunks generated.
+	// When the queue gets empty, the count is reset, so that waiting for the queue is not counted into the total time.
+	int NumChunksGenerated = 0;  // Number of chunks generated since the queue was last empty
+	clock_t GenerationStart = clock();  // Clock tick when the queue started to fill
+	clock_t LastReportTick = clock();  // Clock tick of the last report made (so that performance isn't reported too often)
+	
+	while (!m_ShouldTerminate)
+	{
+		cCSLock Lock(m_CS);
+		while (m_Queue.size() == 0)
+		{
+			if ((NumChunksGenerated > 16) && (clock() - LastReportTick > CLOCKS_PER_SEC))
+			{
+				LOG("Chunk generator performance: %.2f ch/s (%d ch total)",
+					(double)NumChunksGenerated * CLOCKS_PER_SEC/ (clock() - GenerationStart),
+					NumChunksGenerated
+				);
+			}
+			cCSUnlock Unlock(Lock);
+			m_Event.Wait();
+			if (m_ShouldTerminate)
+			{
+				return;
+			}
+			NumChunksGenerated = 0;
+			GenerationStart = clock();
+			LastReportTick = clock();
+		}
+		
+		cChunkCoords coords = m_Queue.front();		// Get next coord from queue
+		m_Queue.erase( m_Queue.begin() );	// Remove coordinate from queue
+		bool SkipEnabled = (m_Queue.size() > QUEUE_SKIP_LIMIT);
+		Lock.Unlock();			// Unlock ASAP
+		m_evtRemoved.Set();
+
+		// Display perf info once in a while:
+		if ((NumChunksGenerated > 16) && (clock() - LastReportTick > 2 * CLOCKS_PER_SEC))
+		{
+			LOG("Chunk generator performance: %.2f ch/s (%d ch total)",
+				(double)NumChunksGenerated * CLOCKS_PER_SEC / (clock() - GenerationStart),
+				NumChunksGenerated
+			);
+			LastReportTick = clock();
+		}
+
+		// Hack for regenerating chunks: if Y != 0, the chunk is considered invalid, even if it has its data set
+		if ((coords.m_ChunkY == 0) && m_World->IsChunkValid(coords.m_ChunkX, coords.m_ChunkZ))
+		{
+			LOGD("Chunk [%d, %d] already generated, skipping generation", coords.m_ChunkX, coords.m_ChunkZ);
+			// Already generated, ignore request
+			continue;
+		}
+		
+		if (SkipEnabled && !m_World->HasChunkAnyClients(coords.m_ChunkX, coords.m_ChunkZ))
+		{
+			LOGWARNING("Chunk generator overloaded, skipping chunk [%d, %d]", coords.m_ChunkX, coords.m_ChunkZ);
+			continue;
+		}
+		
+		LOGD("Generating chunk [%d, %d, %d]", coords.m_ChunkX, coords.m_ChunkY, coords.m_ChunkZ);
+		DoGenerate(coords.m_ChunkX, coords.m_ChunkY, coords.m_ChunkZ);
+		
+		// Save the chunk right after generating, so that we don't have to generate it again on next run
+		m_World->GetStorage().QueueSaveChunk(coords.m_ChunkX, coords.m_ChunkY, coords.m_ChunkZ);
+		
+		NumChunksGenerated++;
+	}  // while (!bStop)
+}
+
+
+
+
+void cChunkGenerator::DoGenerate(int a_ChunkX, int a_ChunkY, int a_ChunkZ)
+{
+	cChunkDesc ChunkDesc(a_ChunkX, a_ChunkZ);
+	cRoot::Get()->GetPluginManager()->CallHookChunkGenerating(m_World, a_ChunkX, a_ChunkZ, &ChunkDesc);
+	m_Generator->DoGenerate(a_ChunkX, a_ChunkZ, ChunkDesc);
+	cRoot::Get()->GetPluginManager()->CallHookChunkGenerated(m_World, a_ChunkX, a_ChunkZ, &ChunkDesc);
+	
+	#ifdef _DEBUG
+	// Verify that the generator has produced valid data:
+	ChunkDesc.VerifyHeightmap();
+	#endif
+	
+	cChunkDef::BlockNibbles BlockMetas;
+	ChunkDesc.CompressBlockMetas(BlockMetas);
+	
+	m_World->SetChunkData(
+		a_ChunkX, a_ChunkZ, 
+		ChunkDesc.GetBlockTypes(), BlockMetas,
+		NULL, NULL,  // We don't have lighting, chunk will be lighted when needed
+		&ChunkDesc.GetHeightMap(), &ChunkDesc.GetBiomeMap(),
+		ChunkDesc.GetEntities(), ChunkDesc.GetBlockEntities(),
+		true
+	);
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cChunkGenerator::cGenerator:
+
+cChunkGenerator::cGenerator::cGenerator(cChunkGenerator & a_ChunkGenerator) :
+	m_ChunkGenerator(a_ChunkGenerator)
+{
+}
+
+
+
+
+
+void cChunkGenerator::cGenerator::Initialize(cWorld * a_World, cIniFile & a_IniFile)
+{
+	m_World = a_World;
+	UNUSED(a_IniFile);
+}
+
+
+
+
+
+EMCSBiome cChunkGenerator::cGenerator::GetBiomeAt(int a_BlockX, int a_BlockZ)
+{
+	cChunkDef::BiomeMap Biomes;
+	int Y = 0;
+	int ChunkX, ChunkZ;
+	cWorld::AbsoluteToRelative(a_BlockX, Y, a_BlockZ, ChunkX, Y, ChunkZ);
+	GenerateBiomes(ChunkX, ChunkZ, Biomes);
+	return cChunkDef::GetBiome(Biomes, a_BlockX, a_BlockZ);
+}
+
+
+
+

src/Generating/ChunkGenerator.h

@@ -0,0 +1,113 @@
+
+// ChunkGenerator.h
+
+// Interfaces to the cChunkGenerator class representing the thread that generates chunks
+
+/*
+The object takes requests for generating chunks and processes them in a separate thread one by one.
+The requests are not added to the queue if there is already a request with the same coords
+Before generating, the thread checks if the chunk hasn't been already generated.
+It is theoretically possible to have multiple generator threads by having multiple instances of this object,
+but then it MAY happen that the chunk is generated twice.
+If the generator queue is overloaded, the generator skips chunks with no clients in them
+*/
+
+
+
+
+
+#pragma once
+
+#include "../OSSupport/IsThread.h"
+#include "../ChunkDef.h"
+
+
+
+
+
+// fwd:
+class cWorld;
+class cIniFile;
+class cChunkDesc;
+
+
+
+
+
+class cChunkGenerator :
+	cIsThread
+{
+	typedef cIsThread super;
+	
+public:
+	/// The interface that a class has to implement to become a generator
+	class cGenerator
+	{
+	public:
+		cGenerator(cChunkGenerator & a_ChunkGenerator);
+		virtual ~cGenerator() {} ;  // Force a virtual destructor
+
+		/// Called to initialize the generator on server startup.
+		virtual void Initialize(cWorld * a_World, cIniFile & a_IniFile);
+		
+		/// Generates the biomes for the specified chunk (directly, not in a separate thread). Used by the world loader if biomes failed loading.
+		virtual void GenerateBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap) = 0;
+
+		/// Returns the biome at the specified coords. Used by ChunkMap if an invalid chunk is queried for biome. Default implementation uses GenerateBiomes().
+		virtual EMCSBiome GetBiomeAt(int a_BlockX, int a_BlockZ);
+
+		/// Called in a separate thread to do the actual chunk generation. Generator should generate into a_ChunkDesc.
+		virtual void DoGenerate(int a_ChunkX, int a_ChunkZ, cChunkDesc & a_ChunkDesc) = 0;
+		
+	protected:
+		cChunkGenerator & m_ChunkGenerator;
+		cWorld          * m_World;
+	} ;
+	
+
+	cChunkGenerator (void);
+	~cChunkGenerator();
+
+	bool Start(cWorld * a_World, cIniFile & a_IniFile);
+	void Stop(void);
+
+	/// Queues the chunk for generation; removes duplicate requests
+	void QueueGenerateChunk(int a_ChunkX, int a_ChunkY, int a_ChunkZ);
+	
+	/// Generates the biomes for the specified chunk (directly, not in a separate thread). Used by the world loader if biomes failed loading.
+	void GenerateBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap);
+	
+	void WaitForQueueEmpty(void);
+	
+	int GetQueueLength(void);
+	
+	int GetSeed(void) const { return m_Seed; }
+	
+	/// Returns the biome at the specified coords. Used by ChunkMap if an invalid chunk is queried for biome
+	EMCSBiome GetBiomeAt(int a_BlockX, int a_BlockZ);
+
+	/// Reads a block type from the ini file; returns the blocktype on success, emits a warning and returns a_Default's representation on failure.
+	static BLOCKTYPE GetIniBlock(cIniFile & a_IniFile, const AString & a_SectionName, const AString & a_ValueName, const AString & a_Default);
+	
+private:
+
+	cWorld * m_World;
+	
+	int m_Seed;
+
+	cCriticalSection m_CS;
+	cChunkCoordsList m_Queue;
+	cEvent           m_Event;       ///< Set when an item is added to the queue or the thread should terminate
+	cEvent           m_evtRemoved;  ///< Set when an item is removed from the queue
+	
+	cGenerator * m_Generator;  ///< The actual generator engine used to generate chunks
+
+	// cIsThread override:
+	virtual void Execute(void) override;
+
+	void DoGenerate(int a_ChunkX, int a_ChunkY, int a_ChunkZ);
+};
+
+
+
+

src/Generating/CompoGen.cpp

@@ -0,0 +1,634 @@
+
+// CompoGen.cpp
+
+/* Implements the various terrain composition generators:
+	- cCompoGenSameBlock
+	- cCompoGenDebugBiomes
+	- cCompoGenClassic
+*/
+
+#include "Globals.h"
+#include "CompoGen.h"
+#include "../BlockID.h"
+#include "../Item.h"
+#include "../LinearUpscale.h"
+#include "../../iniFile/iniFile.h"
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cCompoGenSameBlock:
+
+void cCompoGenSameBlock::ComposeTerrain(cChunkDesc & a_ChunkDesc)
+{
+	a_ChunkDesc.FillBlocks(E_BLOCK_AIR, 0);
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			int Start;
+			if (m_IsBedrocked)
+			{
+				a_ChunkDesc.SetBlockType(x, 0, z, E_BLOCK_BEDROCK);
+				Start = 1;
+			}
+			else
+			{
+				Start = 0;
+			}
+			for (int y = a_ChunkDesc.GetHeight(x, z); y >= Start; y--)
+			{
+				a_ChunkDesc.SetBlockType(x, y, z, m_BlockType);
+			}  // for y
+		}  // for z
+	}  // for x
+}
+
+
+
+
+
+void cCompoGenSameBlock::InitializeCompoGen(cIniFile & a_IniFile)
+{
+	m_BlockType = (BLOCKTYPE)(GetIniItemSet(a_IniFile, "Generator", "SameBlockType", "stone").m_ItemType);
+	m_IsBedrocked = (a_IniFile.GetValueSetI("Generator", "SameBlockBedrocked", 1) != 0);
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cCompoGenDebugBiomes:
+
+void cCompoGenDebugBiomes::ComposeTerrain(cChunkDesc & a_ChunkDesc)
+{
+	static BLOCKTYPE Blocks[] =
+	{
+		E_BLOCK_STONE,
+		E_BLOCK_COBBLESTONE, 
+		E_BLOCK_LOG,
+		E_BLOCK_PLANKS,
+		E_BLOCK_SANDSTONE,
+		E_BLOCK_WOOL,
+		E_BLOCK_COAL_ORE,
+		E_BLOCK_IRON_ORE,
+		E_BLOCK_GOLD_ORE,
+		E_BLOCK_DIAMOND_ORE,
+		E_BLOCK_LAPIS_ORE,
+		E_BLOCK_REDSTONE_ORE,
+		E_BLOCK_IRON_BLOCK,
+		E_BLOCK_GOLD_BLOCK,
+		E_BLOCK_DIAMOND_BLOCK,
+		E_BLOCK_LAPIS_BLOCK,
+		E_BLOCK_BRICK,
+		E_BLOCK_MOSSY_COBBLESTONE,
+		E_BLOCK_OBSIDIAN,
+		E_BLOCK_NETHERRACK,
+		E_BLOCK_SOULSAND,
+		E_BLOCK_NETHER_BRICK,
+		E_BLOCK_BEDROCK,
+	} ;
+	
+	a_ChunkDesc.FillBlocks(E_BLOCK_AIR, 0);
+
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			BLOCKTYPE BlockType = Blocks[a_ChunkDesc.GetBiome(x, z)];
+			for (int y = a_ChunkDesc.GetHeight(x, z); y >= 0; y--)
+			{
+				a_ChunkDesc.SetBlockType(x, y, z, BlockType);
+			}  // for y
+		}  // for z
+	}  // for x
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cCompoGenClassic:
+
+cCompoGenClassic::cCompoGenClassic(void) :
+	m_SeaLevel(60),
+	m_BeachHeight(2),
+	m_BeachDepth(4),
+	m_BlockTop(E_BLOCK_GRASS),
+	m_BlockMiddle(E_BLOCK_DIRT),
+	m_BlockBottom(E_BLOCK_STONE),
+	m_BlockBeach(E_BLOCK_SAND),
+	m_BlockBeachBottom(E_BLOCK_SANDSTONE),
+	m_BlockSea(E_BLOCK_STATIONARY_WATER)
+{
+}
+
+
+
+
+
+void cCompoGenClassic::ComposeTerrain(cChunkDesc & a_ChunkDesc)
+{
+	/* The classic composition means:
+		- 1 layer of grass, 3 of dirt and the rest stone, if the height > sealevel + beachheight
+		- 3 sand and a 1 sandstone, rest stone if between sealevel and sealevel + beachheight
+		- water from waterlevel to height, then 3 sand, 1 sandstone, the rest stone, if water depth < beachdepth
+		- water from waterlevel, then 3 dirt, the rest stone otherwise
+		- bedrock at the bottom
+	*/
+
+	a_ChunkDesc.FillBlocks(E_BLOCK_AIR, 0);
+
+	// The patterns to use for different situations, must be same length!
+	const BLOCKTYPE PatternGround[] = {m_BlockTop,    m_BlockMiddle, m_BlockMiddle, m_BlockMiddle} ;
+	const BLOCKTYPE PatternBeach[]  = {m_BlockBeach,  m_BlockBeach,  m_BlockBeach,  m_BlockBeachBottom} ;
+	const BLOCKTYPE PatternOcean[]  = {m_BlockMiddle, m_BlockMiddle, m_BlockMiddle, m_BlockBottom} ;
+	static int PatternLength = ARRAYCOUNT(PatternGround);
+	ASSERT(ARRAYCOUNT(PatternGround) == ARRAYCOUNT(PatternBeach));
+	ASSERT(ARRAYCOUNT(PatternGround) == ARRAYCOUNT(PatternOcean));
+	
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			int Height = a_ChunkDesc.GetHeight(x, z);
+			const BLOCKTYPE * Pattern;
+			if (Height > m_SeaLevel + m_BeachHeight)
+			{
+				Pattern = PatternGround;
+			}
+			else if (Height > m_SeaLevel - m_BeachDepth)
+			{
+				Pattern = PatternBeach;
+			}
+			else
+			{
+				Pattern = PatternOcean;
+			}
+			
+			// Fill water from sealevel down to height (if any):
+			for (int y = m_SeaLevel; y >= Height; --y)
+			{
+				a_ChunkDesc.SetBlockType(x, y, z, m_BlockSea);
+			}
+			
+			// Fill from height till the bottom:
+			for (int y = Height; y >= 1; y--)
+			{
+				a_ChunkDesc.SetBlockType(x, y, z, (Height - y < PatternLength) ? Pattern[Height - y] : m_BlockBottom);
+			}
+			
+			// The last layer is always bedrock:
+			a_ChunkDesc.SetBlockType(x, 0, z, E_BLOCK_BEDROCK);
+		}  // for x
+	}  // for z
+}
+
+
+
+
+
+void cCompoGenClassic::InitializeCompoGen(cIniFile & a_IniFile)
+{
+	m_SeaLevel         = a_IniFile.GetValueSetI("Generator", "ClassicSeaLevel",    m_SeaLevel);
+	m_BeachHeight      = a_IniFile.GetValueSetI("Generator", "ClassicBeachHeight", m_BeachHeight);
+	m_BeachDepth       = a_IniFile.GetValueSetI("Generator", "ClassicBeachDepth",  m_BeachDepth);
+	m_BlockTop         = (BLOCKTYPE)(GetIniItemSet(a_IniFile, "Generator", "ClassicBlockTop",         "grass").m_ItemType);
+	m_BlockMiddle      = (BLOCKTYPE)(GetIniItemSet(a_IniFile, "Generator", "ClassicBlockMiddle",      "dirt").m_ItemType);
+	m_BlockBottom      = (BLOCKTYPE)(GetIniItemSet(a_IniFile, "Generator", "ClassicBlockBottom",      "stone").m_ItemType);
+	m_BlockBeach       = (BLOCKTYPE)(GetIniItemSet(a_IniFile, "Generator", "ClassicBlockBeach",       "sand").m_ItemType);
+	m_BlockBeachBottom = (BLOCKTYPE)(GetIniItemSet(a_IniFile, "Generator", "ClassicBlockBeachBottom", "sandstone").m_ItemType);
+	m_BlockSea         = (BLOCKTYPE)(GetIniItemSet(a_IniFile, "Generator", "ClassicBlockSea",         "stationarywater").m_ItemType);
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cCompoGenBiomal:
+
+void cCompoGenBiomal::ComposeTerrain(cChunkDesc & a_ChunkDesc)
+{
+	a_ChunkDesc.FillBlocks(E_BLOCK_AIR, 0);
+
+	int ChunkX = a_ChunkDesc.GetChunkX();
+	int ChunkZ = a_ChunkDesc.GetChunkZ();
+	
+	/*
+	_X 2013_04_22:
+	There's no point in generating the whole cubic noise at once, because the noise values are used in
+	only about 20 % of the cases, so the speed gained by precalculating is lost by precalculating too much data
+	*/
+	
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			int Height = a_ChunkDesc.GetHeight(x, z);
+			if (Height > m_SeaLevel)
+			{
+				switch (a_ChunkDesc.GetBiome(x, z))
+				{
+					case biOcean:
+					case biPlains:
+					case biExtremeHills:
+					case biForest:
+					case biTaiga:
+					case biSwampland:
+					case biRiver:
+					case biFrozenOcean:
+					case biFrozenRiver:
+					case biIcePlains:
+					case biIceMountains:
+					case biForestHills:
+					case biTaigaHills:
+					case biExtremeHillsEdge:
+					case biJungle:
+					case biJungleHills:
+					{
+						FillColumnGrass(x, z, Height, a_ChunkDesc.GetBlockTypes());
+						break;
+					}
+					case biDesertHills:
+					case biDesert:
+					case biBeach:
+					{
+						FillColumnSand(x, z, Height, a_ChunkDesc.GetBlockTypes());
+						break;
+					}
+					case biMushroomIsland:
+					case biMushroomShore:
+					{
+						FillColumnMycelium(x, z, Height, a_ChunkDesc.GetBlockTypes());
+						break;
+					}
+					default:
+					{
+						// TODO
+						ASSERT(!"CompoGenBiomal: Biome not implemented yet!");
+						break;
+					}
+				}
+			}
+			else
+			{
+				switch (a_ChunkDesc.GetBiome(x, z))
+				{
+					case biDesert:
+					case biBeach:
+					{
+						// Fill with water, sand, sandstone and stone
+						FillColumnWaterSand(x, z, Height, a_ChunkDesc.GetBlockTypes());
+						break;
+					}
+					default:
+					{
+						// Fill with water, sand/dirt/clay mix and stone
+						if (m_Noise.CubicNoise2D(0.3f * (cChunkDef::Width * ChunkX + x), 0.3f * (cChunkDef::Width * ChunkZ + z)) < 0)
+						{
+							FillColumnWaterSand(x, z, Height, a_ChunkDesc.GetBlockTypes());
+						}
+						else
+						{
+							FillColumnWaterDirt(x, z, Height, a_ChunkDesc.GetBlockTypes());
+						}
+						break;
+					}
+				}  // switch (biome)
+				a_ChunkDesc.SetHeight(x, z, m_SeaLevel + 1);
+			}  // else (under water)
+			a_ChunkDesc.SetBlockType(x, 0, z, E_BLOCK_BEDROCK);
+		}  // for x
+	}  // for z
+}
+
+
+
+
+
+void cCompoGenBiomal::InitializeCompoGen(cIniFile & a_IniFile)
+{
+	m_SeaLevel = a_IniFile.GetValueSetI("Generator", "BiomalSeaLevel", m_SeaLevel) - 1;
+}
+
+
+
+
+
+void cCompoGenBiomal::FillColumnGrass(int a_RelX, int a_RelZ, int a_Height, cChunkDef::BlockTypes & a_BlockTypes)
+{
+	BLOCKTYPE Pattern[] =
+	{
+		E_BLOCK_GRASS,
+		E_BLOCK_DIRT,
+		E_BLOCK_DIRT,
+		E_BLOCK_DIRT,
+	} ;
+	FillColumnPattern(a_RelX, a_RelZ, a_Height, a_BlockTypes, Pattern, ARRAYCOUNT(Pattern));
+	
+	for (int y = a_Height - ARRAYCOUNT(Pattern); y > 0; y--)
+	{
+		cChunkDef::SetBlock(a_BlockTypes, a_RelX, y, a_RelZ, E_BLOCK_STONE);
+	}
+}
+
+
+
+
+
+void cCompoGenBiomal::FillColumnSand(int a_RelX, int a_RelZ, int a_Height, cChunkDef::BlockTypes & a_BlockTypes)
+{
+	BLOCKTYPE Pattern[] =
+	{
+		E_BLOCK_SAND,
+		E_BLOCK_SAND,
+		E_BLOCK_SAND,
+		E_BLOCK_SANDSTONE,
+	} ;
+	FillColumnPattern(a_RelX, a_RelZ, a_Height, a_BlockTypes, Pattern, ARRAYCOUNT(Pattern));
+	
+	for (int y = a_Height - ARRAYCOUNT(Pattern); y > 0; y--)
+	{
+		cChunkDef::SetBlock(a_BlockTypes, a_RelX, y, a_RelZ, E_BLOCK_STONE);
+	}
+}
+
+
+
+
+
+
+void cCompoGenBiomal::FillColumnMycelium (int a_RelX, int a_RelZ, int a_Height, cChunkDef::BlockTypes & a_BlockTypes)
+{
+	BLOCKTYPE Pattern[] =
+	{
+		E_BLOCK_MYCELIUM,
+		E_BLOCK_DIRT,
+		E_BLOCK_DIRT,
+		E_BLOCK_DIRT,
+	} ;
+	FillColumnPattern(a_RelX, a_RelZ, a_Height, a_BlockTypes, Pattern, ARRAYCOUNT(Pattern));
+	
+	for (int y = a_Height - ARRAYCOUNT(Pattern); y > 0; y--)
+	{
+		cChunkDef::SetBlock(a_BlockTypes, a_RelX, y, a_RelZ, E_BLOCK_STONE);
+	}
+}
+
+
+
+
+
+void cCompoGenBiomal::FillColumnWaterSand(int a_RelX, int a_RelZ, int a_Height, cChunkDef::BlockTypes & a_BlockTypes)
+{
+	FillColumnSand(a_RelX, a_RelZ, a_Height, a_BlockTypes);
+	for (int y = a_Height + 1; y <= m_SeaLevel + 1; y++)
+	{
+		cChunkDef::SetBlock(a_BlockTypes, a_RelX, y, a_RelZ, E_BLOCK_STATIONARY_WATER);
+	}
+}
+
+
+
+
+
+void cCompoGenBiomal::FillColumnWaterDirt(int a_RelX, int a_RelZ, int a_Height, cChunkDef::BlockTypes & a_BlockTypes)
+{
+	// Dirt
+	BLOCKTYPE Pattern[] =
+	{
+		E_BLOCK_DIRT,
+		E_BLOCK_DIRT,
+		E_BLOCK_DIRT,
+		E_BLOCK_DIRT,
+	} ;
+	FillColumnPattern(a_RelX, a_RelZ, a_Height, a_BlockTypes, Pattern, ARRAYCOUNT(Pattern));
+
+	for (int y = a_Height - ARRAYCOUNT(Pattern); y > 0; y--)
+	{
+		cChunkDef::SetBlock(a_BlockTypes, a_RelX, y, a_RelZ, E_BLOCK_STONE);
+	}
+	for (int y = a_Height + 1; y <= m_SeaLevel + 1; y++)
+	{
+		cChunkDef::SetBlock(a_BlockTypes, a_RelX, y, a_RelZ, E_BLOCK_STATIONARY_WATER);
+	}
+}
+
+
+
+
+
+
+void cCompoGenBiomal::FillColumnPattern(int a_RelX, int a_RelZ, int a_Height, cChunkDef::BlockTypes & a_BlockTypes, const BLOCKTYPE * a_Pattern, int a_PatternSize)
+{
+	for (int y = a_Height, idx = 0; (y >= 0) && (idx < a_PatternSize); y--, idx++)
+	{
+		cChunkDef::SetBlock(a_BlockTypes, a_RelX, y, a_RelZ, a_Pattern[idx]);
+	}
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cCompoGenNether:
+
+cCompoGenNether::cCompoGenNether(int a_Seed) :
+	m_Noise1(a_Seed + 10),
+	m_Noise2(a_Seed * a_Seed * 10 + a_Seed * 1000 + 6000),
+	m_Threshold(0)
+{
+}
+
+
+
+
+
+void cCompoGenNether::ComposeTerrain(cChunkDesc & a_ChunkDesc)
+{
+	HEIGHTTYPE MaxHeight = a_ChunkDesc.GetMaxHeight();
+	
+	const int SEGMENT_HEIGHT = 8;
+	const int INTERPOL_X = 16;  // Must be a divisor of 16
+	const int INTERPOL_Z = 16;  // Must be a divisor of 16
+	// Interpolate the chunk in 16 * SEGMENT_HEIGHT * 16 "segments", each SEGMENT_HEIGHT blocks high and each linearly interpolated separately.
+	// Have two buffers, one for the lowest floor and one for the highest floor, so that Y-interpolation can be done between them
+	// Then swap the buffers and use the previously-top one as the current-bottom, without recalculating it.
+	
+	int FloorBuf1[17 * 17];
+	int FloorBuf2[17 * 17];
+	int * FloorHi = FloorBuf1;
+	int * FloorLo = FloorBuf2;
+	int BaseX = a_ChunkDesc.GetChunkX() * cChunkDef::Width;
+	int BaseZ = a_ChunkDesc.GetChunkZ() * cChunkDef::Width;
+	
+	// Interpolate the lowest floor:
+	for (int z = 0; z <= 16 / INTERPOL_Z; z++) for (int x = 0; x <= 16 / INTERPOL_X; x++)
+	{
+		FloorLo[INTERPOL_X * x + 17 * INTERPOL_Z * z] = 
+			m_Noise1.IntNoise3DInt(BaseX + INTERPOL_X * x, 0, BaseZ + INTERPOL_Z * z) * 
+			m_Noise2.IntNoise3DInt(BaseX + INTERPOL_X * x, 0, BaseZ + INTERPOL_Z * z) /
+			256;
+	}  // for x, z - FloorLo[]
+	LinearUpscale2DArrayInPlace(FloorLo, 17, 17, INTERPOL_X, INTERPOL_Z);
+	
+	// Interpolate segments:
+	for (int Segment = 0; Segment < MaxHeight; Segment += SEGMENT_HEIGHT)
+	{
+		// First update the high floor:
+		for (int z = 0; z <= 16 / INTERPOL_Z; z++) for (int x = 0; x <= 16 / INTERPOL_X; x++)
+		{
+			FloorHi[INTERPOL_X * x + 17 * INTERPOL_Z * z] =
+				m_Noise1.IntNoise3DInt(BaseX + INTERPOL_X * x, Segment + SEGMENT_HEIGHT, BaseZ + INTERPOL_Z * z) *
+				m_Noise2.IntNoise3DInt(BaseX + INTERPOL_Z * x, Segment + SEGMENT_HEIGHT, BaseZ + INTERPOL_Z * z) /
+				256;
+		}  // for x, z - FloorLo[]
+		LinearUpscale2DArrayInPlace(FloorHi, 17, 17, INTERPOL_X, INTERPOL_Z);
+		
+		// Interpolate between FloorLo and FloorHi:
+		for (int z = 0; z < 16; z++) for (int x = 0; x < 16; x++)
+		{
+			int Lo = FloorLo[x + 17 * z] / 256;
+			int Hi = FloorHi[x + 17 * z] / 256;
+			for (int y = 0; y < SEGMENT_HEIGHT; y++)
+			{
+				int Val = Lo + (Hi - Lo) * y / SEGMENT_HEIGHT;
+				a_ChunkDesc.SetBlockType(x, y + Segment, z, (Val < m_Threshold) ? E_BLOCK_NETHERRACK : E_BLOCK_AIR);
+			}
+		}
+		
+		// Swap the floors:
+		std::swap(FloorLo, FloorHi);
+	}
+	
+	// Bedrock at the bottom and at the top:
+	for (int z = 0; z < 16; z++) for (int x = 0; x < 16; x++)
+	{
+		a_ChunkDesc.SetBlockType(x, 0, z, E_BLOCK_BEDROCK);
+		a_ChunkDesc.SetBlockType(x, a_ChunkDesc.GetHeight(x, z), z, E_BLOCK_BEDROCK);
+	}
+}
+
+
+
+
+
+void cCompoGenNether::InitializeCompoGen(cIniFile & a_IniFile)
+{
+	m_Threshold = a_IniFile.GetValueSetI("Generator", "NetherThreshold", m_Threshold);
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cCompoGenCache:
+
+cCompoGenCache::cCompoGenCache(cTerrainCompositionGen & a_Underlying, int a_CacheSize) :
+	m_Underlying(a_Underlying),
+	m_CacheSize(a_CacheSize),
+	m_CacheOrder(new int[a_CacheSize]),
+	m_CacheData(new sCacheData[a_CacheSize]),
+	m_NumHits(0),
+	m_NumMisses(0),
+	m_TotalChain(0)
+{
+	for (int i = 0; i < m_CacheSize; i++)
+	{
+		m_CacheOrder[i] = i;
+		m_CacheData[i].m_ChunkX = 0x7fffffff;
+		m_CacheData[i].m_ChunkZ = 0x7fffffff;
+	}
+}
+
+
+
+
+
+cCompoGenCache::~cCompoGenCache()
+{
+	delete[] m_CacheData;
+	delete[] m_CacheOrder;
+}
+
+
+
+
+
+void cCompoGenCache::ComposeTerrain(cChunkDesc & a_ChunkDesc)
+{
+	#ifdef _DEBUG
+	if (((m_NumHits + m_NumMisses) % 1024) == 10)
+	{
+		LOGD("CompoGenCache: %d hits, %d misses, saved %.2f %%", m_NumHits, m_NumMisses, 100.0 * m_NumHits / (m_NumHits + m_NumMisses));
+		LOGD("CompoGenCache: Avg cache chain length: %.2f", (float)m_TotalChain / m_NumHits);
+	}
+	#endif  // _DEBUG
+	
+	int ChunkX = a_ChunkDesc.GetChunkX();
+	int ChunkZ = a_ChunkDesc.GetChunkZ();
+	
+	for (int i = 0; i < m_CacheSize; i++)
+	{
+		if (
+			(m_CacheData[m_CacheOrder[i]].m_ChunkX != ChunkX) ||
+			(m_CacheData[m_CacheOrder[i]].m_ChunkZ != ChunkZ)
+		)
+		{
+			continue;
+		}
+		// Found it in the cache
+		int Idx = m_CacheOrder[i];
+		
+		// Move to front:
+		for (int j = i; j > 0; j--)
+		{
+			m_CacheOrder[j] = m_CacheOrder[j - 1];
+		}
+		m_CacheOrder[0] = Idx;
+		
+		// Use the cached data:
+		memcpy(a_ChunkDesc.GetBlockTypes(),             m_CacheData[Idx].m_BlockTypes, sizeof(a_ChunkDesc.GetBlockTypes()));
+		memcpy(a_ChunkDesc.GetBlockMetasUncompressed(), m_CacheData[Idx].m_BlockMetas, sizeof(a_ChunkDesc.GetBlockMetasUncompressed()));
+		
+		m_NumHits++;
+		m_TotalChain += i;
+		return;
+	}  // for i - cache
+	
+	// Not in the cache:
+	m_NumMisses++;
+	m_Underlying.ComposeTerrain(a_ChunkDesc);
+	
+	// Insert it as the first item in the MRU order:
+	int Idx = m_CacheOrder[m_CacheSize - 1];
+	for (int i = m_CacheSize - 1; i > 0; i--)
+	{
+		m_CacheOrder[i] = m_CacheOrder[i - 1];
+	}  // for i - m_CacheOrder[]
+	m_CacheOrder[0] = Idx;
+	memcpy(m_CacheData[Idx].m_BlockTypes, a_ChunkDesc.GetBlockTypes(),             sizeof(a_ChunkDesc.GetBlockTypes()));
+	memcpy(m_CacheData[Idx].m_BlockMetas, a_ChunkDesc.GetBlockMetasUncompressed(), sizeof(a_ChunkDesc.GetBlockMetasUncompressed()));
+	m_CacheData[Idx].m_ChunkX = ChunkX;
+	m_CacheData[Idx].m_ChunkZ = ChunkZ;
+}
+
+
+
+
+
+void cCompoGenCache::InitializeCompoGen(cIniFile & a_IniFile)
+{
+	m_Underlying.InitializeCompoGen(a_IniFile);
+}
+
+
+
+

src/Generating/CompoGen.h

@@ -0,0 +1,182 @@
+
+// CompoGen.h
+
+/* Interfaces to the various terrain composition generators:
+	- cCompoGenSameBlock
+	- cCompoGenDebugBiomes
+	- cCompoGenClassic
+	- cCompoGenBiomal
+	- cCompoGenNether
+	- cCompoGenCache
+*/
+
+
+
+
+
+#pragma once
+
+#include "ComposableGenerator.h"
+#include "../Noise.h"
+
+
+
+
+
+class cCompoGenSameBlock :
+	public cTerrainCompositionGen
+{
+public:
+	cCompoGenSameBlock(void) :
+		m_BlockType(E_BLOCK_STONE),
+		m_IsBedrocked(true)
+	{}
+	
+protected:
+
+	BLOCKTYPE m_BlockType;
+	bool      m_IsBedrocked;
+	
+	// cTerrainCompositionGen overrides:
+	virtual void ComposeTerrain(cChunkDesc & a_ChunkDesc) override;
+	virtual void InitializeCompoGen(cIniFile & a_IniFile) override;
+} ;
+
+
+
+
+
+class cCompoGenDebugBiomes :
+	public cTerrainCompositionGen
+{
+public:
+	cCompoGenDebugBiomes(void) {}
+	
+protected:
+	
+	// cTerrainCompositionGen overrides:
+	virtual void ComposeTerrain(cChunkDesc & a_ChunkDesc) override;
+} ;
+
+
+
+
+
+class cCompoGenClassic :
+	public cTerrainCompositionGen
+{
+public:
+	cCompoGenClassic(void);
+	
+protected:
+
+	int m_SeaLevel;
+	int m_BeachHeight;
+	int m_BeachDepth;
+	BLOCKTYPE m_BlockTop;
+	BLOCKTYPE m_BlockMiddle;
+	BLOCKTYPE m_BlockBottom;
+	BLOCKTYPE m_BlockBeach;
+	BLOCKTYPE m_BlockBeachBottom;
+	BLOCKTYPE m_BlockSea;
+	
+	// cTerrainCompositionGen overrides:
+	virtual void ComposeTerrain(cChunkDesc & a_ChunkDesc) override;
+	virtual void InitializeCompoGen(cIniFile & a_IniFile) override;
+} ;
+
+
+
+
+
+class cCompoGenBiomal :
+	public cTerrainCompositionGen
+{
+public:
+	cCompoGenBiomal(int a_Seed) :
+		m_Noise(a_Seed + 1000),
+		m_SeaLevel(62)
+	{
+	}
+	
+protected:
+
+	cNoise m_Noise;
+	int    m_SeaLevel;
+	
+	// cTerrainCompositionGen overrides:
+	virtual void ComposeTerrain(cChunkDesc & a_ChunkDesc) override;
+	virtual void InitializeCompoGen(cIniFile & a_IniFile) override;
+	
+	void FillColumnGrass    (int a_RelX, int a_RelZ, int a_Height, cChunkDef::BlockTypes & a_BlockTypes);
+	void FillColumnSand     (int a_RelX, int a_RelZ, int a_Height, cChunkDef::BlockTypes & a_BlockTypes);
+	void FillColumnMycelium (int a_RelX, int a_RelZ, int a_Height, cChunkDef::BlockTypes & a_BlockTypes);
+	void FillColumnWaterSand(int a_RelX, int a_RelZ, int a_Height, cChunkDef::BlockTypes & a_BlockTypes);
+	void FillColumnWaterDirt(int a_RelX, int a_RelZ, int a_Height, cChunkDef::BlockTypes & a_BlockTypes);
+	
+	void FillColumnPattern  (int a_RelX, int a_RelZ, int a_Height, cChunkDef::BlockTypes & a_BlockTypes, const BLOCKTYPE * a_Pattern, int a_PatternSize);
+} ;
+
+
+
+
+
+class cCompoGenNether :
+	public cTerrainCompositionGen
+{
+public:
+	cCompoGenNether(int a_Seed);
+	
+protected:
+	cNoise m_Noise1;
+	cNoise m_Noise2;
+	
+	int m_Threshold;
+	
+	// cTerrainCompositionGen overrides:
+	virtual void ComposeTerrain(cChunkDesc & a_ChunkDesc) override;
+	virtual void InitializeCompoGen(cIniFile & a_IniFile) override;
+} ;
+
+
+
+
+
+/// Caches most-recently-used chunk composition of another composition generator. Caches only the types and metas
+class cCompoGenCache :
+	public cTerrainCompositionGen
+{
+public:
+	cCompoGenCache(cTerrainCompositionGen & a_Underlying, int a_CacheSize);  // Doesn't take ownership of a_Underlying
+	~cCompoGenCache();
+	
+	// cTerrainCompositionGen override:
+	virtual void ComposeTerrain(cChunkDesc & a_ChunkDesc) override;
+	virtual void InitializeCompoGen(cIniFile & a_IniFile) override;
+	
+protected:
+
+	cTerrainCompositionGen & m_Underlying;
+	
+	struct sCacheData
+	{
+		int m_ChunkX;
+		int m_ChunkZ;
+		cChunkDef::BlockTypes        m_BlockTypes;
+		cChunkDesc::BlockNibbleBytes m_BlockMetas;  // The metas are uncompressed, 1 meta per byte
+	} ;
+	
+	// To avoid moving large amounts of data for the MRU behavior, we MRU-ize indices to an array of the actual data
+	int          m_CacheSize;
+	int *        m_CacheOrder;  // MRU-ized order, indices into m_CacheData array
+	sCacheData * m_CacheData;   // m_CacheData[m_CacheOrder[0]] is the most recently used
+	
+	// Cache statistics
+	int m_NumHits;
+	int m_NumMisses;
+	int m_TotalChain;  // Number of cache items walked to get to a hit (only added for hits)
+} ;
+
+
+
+

src/Generating/ComposableGenerator.cpp

@@ -0,0 +1,501 @@
+
+// ComposableGenerator.cpp
+
+// Implements the cComposableGenerator class representing the chunk generator that takes the composition approach to generating chunks
+
+#include "Globals.h"
+
+#include "ComposableGenerator.h"
+#include "../World.h"
+#include "../../iniFile/iniFile.h"
+#include "../Root.h"
+
+// Individual composed algorithms:
+#include "BioGen.h"
+#include "HeiGen.h"
+#include "CompoGen.h"
+#include "StructGen.h"
+#include "FinishGen.h"
+
+#include "Caves.h"
+#include "DistortedHeightmap.h"
+#include "EndGen.h"
+#include "MineShafts.h"
+#include "Noise3DGenerator.h"
+#include "Ravines.h"
+
+
+
+
+
+
+
+
+
+
+cComposableGenerator::cComposableGenerator(cChunkGenerator & a_ChunkGenerator) :
+	super(a_ChunkGenerator),
+	m_BiomeGen(NULL),
+	m_HeightGen(NULL),
+	m_CompositionGen(NULL),
+	m_UnderlyingBiomeGen(NULL),
+	m_UnderlyingHeightGen(NULL),
+	m_UnderlyingCompositionGen(NULL)
+{
+}
+
+
+
+
+
+cComposableGenerator::~cComposableGenerator()
+{
+	// Delete the generating composition:
+	for (cFinishGenList::const_iterator itr = m_FinishGens.begin(); itr != m_FinishGens.end(); ++itr)
+	{
+		delete *itr;
+	}
+	m_FinishGens.clear();
+	for (cStructureGenList::const_iterator itr = m_StructureGens.begin(); itr != m_StructureGens.end(); ++itr)
+	{
+		delete *itr;
+	}
+	m_StructureGens.clear();
+
+	delete m_CompositionGen;
+	m_CompositionGen = NULL;
+	delete m_HeightGen;
+	m_HeightGen = NULL;
+	delete m_BiomeGen;
+	m_BiomeGen = NULL;
+	delete m_UnderlyingCompositionGen;
+	m_UnderlyingCompositionGen = NULL;
+	delete m_UnderlyingHeightGen;
+	m_UnderlyingHeightGen = NULL;
+	delete m_UnderlyingBiomeGen;
+	m_UnderlyingBiomeGen = NULL;
+}
+
+
+
+
+
+void cComposableGenerator::Initialize(cWorld * a_World, cIniFile & a_IniFile)
+{
+	super::Initialize(a_World, a_IniFile);
+	
+	InitBiomeGen(a_IniFile);
+	InitHeightGen(a_IniFile);
+	InitCompositionGen(a_IniFile);
+	InitStructureGens(a_IniFile);
+	InitFinishGens(a_IniFile);
+}
+
+
+
+
+
+void cComposableGenerator::GenerateBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap)
+{
+	if (m_BiomeGen != NULL)  // Quick fix for generator deinitializing before the world storage finishes loading
+	{
+		m_BiomeGen->GenBiomes(a_ChunkX, a_ChunkZ, a_BiomeMap);
+	}
+}
+
+
+
+
+
+void cComposableGenerator::DoGenerate(int a_ChunkX, int a_ChunkZ, cChunkDesc & a_ChunkDesc)
+{
+	if (a_ChunkDesc.IsUsingDefaultBiomes())
+	{
+		m_BiomeGen->GenBiomes(a_ChunkX, a_ChunkZ, a_ChunkDesc.GetBiomeMap());
+	}
+	
+	if (a_ChunkDesc.IsUsingDefaultHeight())
+	{
+		m_HeightGen->GenHeightMap(a_ChunkX, a_ChunkZ, a_ChunkDesc.GetHeightMap());
+	}
+	
+	if (a_ChunkDesc.IsUsingDefaultComposition())
+	{
+		m_CompositionGen->ComposeTerrain(a_ChunkDesc);
+	}
+
+	if (a_ChunkDesc.IsUsingDefaultStructures())
+	{	
+		for (cStructureGenList::iterator itr = m_StructureGens.begin(); itr != m_StructureGens.end(); ++itr)
+		{
+			(*itr)->GenStructures(a_ChunkDesc);
+		}   // for itr - m_StructureGens[]
+	}
+	
+	if (a_ChunkDesc.IsUsingDefaultFinish())
+	{
+		for (cFinishGenList::iterator itr = m_FinishGens.begin(); itr != m_FinishGens.end(); ++itr)
+		{
+			(*itr)->GenFinish(a_ChunkDesc);
+		}  // for itr - m_FinishGens[]
+	}
+}
+
+
+
+
+
+void cComposableGenerator::InitBiomeGen(cIniFile & a_IniFile)
+{
+	AString BiomeGenName = a_IniFile.GetValueSet("Generator", "BiomeGen", "");
+	if (BiomeGenName.empty())
+	{
+		LOGWARN("[Generator] BiomeGen value not set in world.ini, using \"MultiStepMap\".");
+		BiomeGenName = "MultiStepMap";
+	}
+	
+	int Seed = m_ChunkGenerator.GetSeed();
+	bool CacheOffByDefault = false;
+	if (NoCaseCompare(BiomeGenName, "constant") == 0)
+	{
+		m_BiomeGen = new cBioGenConstant;
+		CacheOffByDefault = true;  // we're generating faster than a cache would retrieve data :)
+	}
+	else if (NoCaseCompare(BiomeGenName, "checkerboard") == 0)
+	{
+		m_BiomeGen = new cBioGenCheckerboard;
+		CacheOffByDefault = true;  // we're (probably) generating faster than a cache would retrieve data
+	}
+	else if (NoCaseCompare(BiomeGenName, "voronoi") == 0)
+	{
+		m_BiomeGen = new cBioGenVoronoi(Seed);
+	}
+	else if (NoCaseCompare(BiomeGenName, "distortedvoronoi") == 0)
+	{
+		m_BiomeGen = new cBioGenDistortedVoronoi(Seed);
+	}
+	else
+	{
+		if (NoCaseCompare(BiomeGenName, "multistepmap") != 0)
+		{
+			LOGWARNING("Unknown BiomeGen \"%s\", using \"MultiStepMap\" instead.", BiomeGenName.c_str());
+		}
+		m_BiomeGen = new cBioGenMultiStepMap(Seed);
+
+		/*
+		// Performance-testing:
+		LOGINFO("Measuring performance of cBioGenMultiStepMap...");
+		clock_t BeginTick = clock();
+		for (int x = 0; x < 5000; x++)
+		{
+			cChunkDef::BiomeMap Biomes;
+			m_BiomeGen->GenBiomes(x * 5, x * 5, Biomes);
+		}
+		clock_t Duration = clock() - BeginTick;
+		LOGINFO("cBioGenMultiStepMap for 5000 chunks took %d ticks (%.02f sec)", Duration, (double)Duration / CLOCKS_PER_SEC);
+		//*/
+	}
+	
+	// Add a cache, if requested:
+	int CacheSize = a_IniFile.GetValueSetI("Generator", "BiomeGenCacheSize", CacheOffByDefault ? 0 : 64);
+	if (CacheSize > 0)
+	{
+		if (CacheSize < 4)
+		{
+			LOGWARNING("Biomegen cache size set too low, would hurt performance instead of helping. Increasing from %d to %d", 
+				CacheSize, 4
+			);
+			CacheSize = 4;
+		}
+		LOGD("Using a cache for biomegen of size %d.", CacheSize);
+		m_UnderlyingBiomeGen = m_BiomeGen;
+		m_BiomeGen = new cBioGenCache(m_UnderlyingBiomeGen, CacheSize);
+	}
+	m_BiomeGen->InitializeBiomeGen(a_IniFile);
+}
+
+
+
+
+
+void cComposableGenerator::InitHeightGen(cIniFile & a_IniFile)
+{
+	AString HeightGenName = a_IniFile.GetValueSet("Generator", "HeightGen", "");
+	if (HeightGenName.empty())
+	{
+		LOGWARN("[Generator] HeightGen value not set in world.ini, using \"Biomal\".");
+		HeightGenName = "Biomal";
+	}
+	
+	int Seed = m_ChunkGenerator.GetSeed();
+	bool CacheOffByDefault = false;
+	if (NoCaseCompare(HeightGenName, "flat") == 0)
+	{
+		m_HeightGen = new cHeiGenFlat;
+		CacheOffByDefault = true;  // We're generating faster than a cache would retrieve data
+	}
+	else if (NoCaseCompare(HeightGenName, "classic") == 0)
+	{
+		m_HeightGen = new cHeiGenClassic(Seed);
+	}
+	else if (NoCaseCompare(HeightGenName, "DistortedHeightmap") == 0)
+	{
+		m_HeightGen = new cDistortedHeightmap(Seed, *m_BiomeGen);
+	}
+	else if (NoCaseCompare(HeightGenName, "End") == 0)
+	{
+		m_HeightGen = new cEndGen(Seed);
+	}
+	else if (NoCaseCompare(HeightGenName, "Noise3D") == 0)
+	{
+		m_HeightGen = new cNoise3DComposable(Seed);
+	}
+	else  // "biomal" or <not found>
+	{
+		if (NoCaseCompare(HeightGenName, "biomal") != 0)
+		{
+			LOGWARN("Unknown HeightGen \"%s\", using \"Biomal\" instead.", HeightGenName.c_str());
+		}
+		m_HeightGen = new cHeiGenBiomal(Seed, *m_BiomeGen);
+
+		/*
+		// Performance-testing:
+		LOGINFO("Measuring performance of cHeiGenBiomal...");
+		clock_t BeginTick = clock();
+		for (int x = 0; x < 500; x++)
+		{
+			cChunkDef::HeightMap Heights;
+			m_HeightGen->GenHeightMap(x * 5, x * 5, Heights);
+		}
+		clock_t Duration = clock() - BeginTick;
+		LOGINFO("HeightGen for 500 chunks took %d ticks (%.02f sec)", Duration, (double)Duration / CLOCKS_PER_SEC);
+		//*/
+	}
+	
+	// Read the settings:
+	m_HeightGen->InitializeHeightGen(a_IniFile);
+	
+	// Add a cache, if requested:
+	int CacheSize = a_IniFile.GetValueSetI("Generator", "HeightGenCacheSize", CacheOffByDefault ? 0 : 64);
+	if (CacheSize > 0)
+	{
+		if (CacheSize < 4)
+		{
+			LOGWARNING("Heightgen cache size set too low, would hurt performance instead of helping. Increasing from %d to %d", 
+				CacheSize, 4
+			);
+			CacheSize = 4;
+		}
+		LOGD("Using a cache for Heightgen of size %d.", CacheSize);
+		m_UnderlyingHeightGen = m_HeightGen;
+		m_HeightGen = new cHeiGenCache(*m_UnderlyingHeightGen, CacheSize);
+	}
+}
+
+
+
+
+
+void cComposableGenerator::InitCompositionGen(cIniFile & a_IniFile)
+{
+	int Seed = m_ChunkGenerator.GetSeed();
+	AString CompoGenName = a_IniFile.GetValueSet("Generator", "CompositionGen", "");
+	if (CompoGenName.empty())
+	{
+		LOGWARN("[Generator] CompositionGen value not set in world.ini, using \"Biomal\".");
+		CompoGenName = "Biomal";
+	}
+	if (NoCaseCompare(CompoGenName, "sameblock") == 0)
+	{
+		m_CompositionGen = new cCompoGenSameBlock;
+	}
+	else if (NoCaseCompare(CompoGenName, "debugbiomes") == 0)
+	{
+		m_CompositionGen = new cCompoGenDebugBiomes;
+	}
+	else if (NoCaseCompare(CompoGenName, "classic") == 0)
+	{
+		m_CompositionGen = new cCompoGenClassic;
+	}
+	else if (NoCaseCompare(CompoGenName, "DistortedHeightmap") == 0)
+	{
+		m_CompositionGen = new cDistortedHeightmap(Seed, *m_BiomeGen);
+	}
+	else if (NoCaseCompare(CompoGenName, "end") == 0)
+	{
+		m_CompositionGen = new cEndGen(Seed);
+	}
+	else if (NoCaseCompare(CompoGenName, "nether") == 0)
+	{
+		m_CompositionGen = new cCompoGenNether(Seed);
+	}
+	else if (NoCaseCompare(CompoGenName, "Noise3D") == 0)
+	{
+		m_CompositionGen = new cNoise3DComposable(m_ChunkGenerator.GetSeed());
+	}
+	else
+	{
+		if (NoCaseCompare(CompoGenName, "biomal") != 0)
+		{
+			LOGWARN("Unknown CompositionGen \"%s\", using \"biomal\" instead.", CompoGenName.c_str());
+		}
+		m_CompositionGen = new cCompoGenBiomal(Seed);
+
+		/*
+		// Performance-testing:
+		LOGINFO("Measuring performance of cCompoGenBiomal...");
+		clock_t BeginTick = clock();
+		for (int x = 0; x < 500; x++)
+		{
+			cChunkDesc Desc(200 + x * 8, 200 + x * 8);
+			m_BiomeGen->GenBiomes(Desc.GetChunkX(), Desc.GetChunkZ(), Desc.GetBiomeMap());
+			m_HeightGen->GenHeightMap(Desc.GetChunkX(), Desc.GetChunkZ(), Desc.GetHeightMap());
+			m_CompositionGen->ComposeTerrain(Desc);
+		}
+		clock_t Duration = clock() - BeginTick;
+		LOGINFO("CompositionGen for 500 chunks took %d ticks (%.02f sec)", Duration, (double)Duration / CLOCKS_PER_SEC);
+		//*/
+	}
+	
+	// Read the settings from the ini file:
+	m_CompositionGen->InitializeCompoGen(a_IniFile);
+	
+	int CompoGenCacheSize = a_IniFile.GetValueSetI("Generator", "CompositionGenCacheSize", 64);
+	if (CompoGenCacheSize > 1)
+	{
+		m_UnderlyingCompositionGen = m_CompositionGen;
+		m_CompositionGen = new cCompoGenCache(*m_UnderlyingCompositionGen, 32);
+	}
+}
+
+
+
+
+
+void cComposableGenerator::InitStructureGens(cIniFile & a_IniFile)
+{
+	AString Structures = a_IniFile.GetValueSet("Generator", "Structures", "Ravines, WormNestCaves, WaterLakes, LavaLakes, OreNests, Trees");
+
+	int Seed = m_ChunkGenerator.GetSeed();
+	AStringVector Str = StringSplitAndTrim(Structures, ",");
+	for (AStringVector::const_iterator itr = Str.begin(); itr != Str.end(); ++itr)
+	{
+		if (NoCaseCompare(*itr, "DualRidgeCaves") == 0)
+		{
+			float Threshold = (float)a_IniFile.GetValueSetF("Generator", "DualRidgeCavesThreshold", 0.3);
+			m_StructureGens.push_back(new cStructGenDualRidgeCaves(Seed, Threshold));
+		}
+		else if (NoCaseCompare(*itr, "DirectOverhangs") == 0)
+		{
+			m_StructureGens.push_back(new cStructGenDirectOverhangs(Seed));
+		}
+		else if (NoCaseCompare(*itr, "DistortedMembraneOverhangs") == 0)
+		{
+			m_StructureGens.push_back(new cStructGenDistortedMembraneOverhangs(Seed));
+		}
+		else if (NoCaseCompare(*itr, "LavaLakes") == 0)
+		{
+			int Probability = a_IniFile.GetValueSetI("Generator", "LavaLakesProbability", 10);
+			m_StructureGens.push_back(new cStructGenLakes(Seed * 5 + 16873, E_BLOCK_STATIONARY_LAVA, *m_HeightGen, Probability));
+		}
+		else if (NoCaseCompare(*itr, "MarbleCaves") == 0)
+		{
+			m_StructureGens.push_back(new cStructGenMarbleCaves(Seed));
+		}
+		else if (NoCaseCompare(*itr, "MineShafts") == 0)
+		{
+			int GridSize        = a_IniFile.GetValueSetI("Generator", "MineShaftsGridSize",        512);
+			int MaxSystemSize   = a_IniFile.GetValueSetI("Generator", "MineShaftsMaxSystemSize",   160);
+			int ChanceCorridor  = a_IniFile.GetValueSetI("Generator", "MineShaftsChanceCorridor",  600);
+			int ChanceCrossing  = a_IniFile.GetValueSetI("Generator", "MineShaftsChanceCrossing",  200);
+			int ChanceStaircase = a_IniFile.GetValueSetI("Generator", "MineShaftsChanceStaircase", 200);
+			m_StructureGens.push_back(new cStructGenMineShafts(
+				Seed, GridSize, MaxSystemSize, 
+				ChanceCorridor, ChanceCrossing, ChanceStaircase
+			));
+		}
+		else if (NoCaseCompare(*itr, "OreNests") == 0)
+		{
+			m_StructureGens.push_back(new cStructGenOreNests(Seed));
+		}
+		else if (NoCaseCompare(*itr, "Ravines") == 0)
+		{
+			m_StructureGens.push_back(new cStructGenRavines(Seed, 128));
+		}
+		else if (NoCaseCompare(*itr, "Trees") == 0)
+		{
+			m_StructureGens.push_back(new cStructGenTrees(Seed, m_BiomeGen, m_HeightGen, m_CompositionGen));
+		}
+		else if (NoCaseCompare(*itr, "WaterLakes") == 0)
+		{
+			int Probability = a_IniFile.GetValueSetI("Generator", "WaterLakesProbability", 25);
+			m_StructureGens.push_back(new cStructGenLakes(Seed * 3 + 652, E_BLOCK_STATIONARY_WATER, *m_HeightGen, Probability));
+		}
+		else if (NoCaseCompare(*itr, "WormNestCaves") == 0)
+		{
+			m_StructureGens.push_back(new cStructGenWormNestCaves(Seed));
+		}
+		else
+		{
+			LOGWARNING("Unknown structure generator: \"%s\". Ignoring.", itr->c_str());
+		}
+	}  // for itr - Str[]
+}
+
+
+
+
+
+void cComposableGenerator::InitFinishGens(cIniFile & a_IniFile)
+{
+	int Seed = m_ChunkGenerator.GetSeed();
+	AString Structures = a_IniFile.GetValueSet("Generator", "Finishers", "SprinkleFoliage,Ice,Snow,Lilypads,BottomLava,DeadBushes,PreSimulator");
+
+	AStringVector Str = StringSplitAndTrim(Structures, ",");
+	for (AStringVector::const_iterator itr = Str.begin(); itr != Str.end(); ++itr)
+	{
+		// Finishers, alpha-sorted:
+		if (NoCaseCompare(*itr, "BottomLava") == 0)
+		{
+			int DefaultBottomLavaLevel = (m_World->GetDimension() == dimNether) ? 30 : 10;
+			int BottomLavaLevel = a_IniFile.GetValueSetI("Generator", "BottomLavaLevel", DefaultBottomLavaLevel);
+			m_FinishGens.push_back(new cFinishGenBottomLava(BottomLavaLevel));
+		}
+		else if (NoCaseCompare(*itr, "DeadBushes") == 0)
+		{
+			m_FinishGens.push_back(new cFinishGenSingleBiomeSingleTopBlock(Seed, E_BLOCK_DEAD_BUSH, biDesert, 2, E_BLOCK_SAND, E_BLOCK_SAND));
+		}
+		else if (NoCaseCompare(*itr, "Ice") == 0)
+		{
+			m_FinishGens.push_back(new cFinishGenIce);
+		}
+		else if (NoCaseCompare(*itr, "LavaSprings") == 0)
+		{
+			m_FinishGens.push_back(new cFinishGenFluidSprings(Seed, E_BLOCK_LAVA, a_IniFile, *m_World));
+		}
+		else if (NoCaseCompare(*itr, "Lilypads") == 0)
+		{
+			m_FinishGens.push_back(new cFinishGenSingleBiomeSingleTopBlock(Seed, E_BLOCK_LILY_PAD, biSwampland, 4, E_BLOCK_WATER, E_BLOCK_STATIONARY_WATER));
+		}
+		else if (NoCaseCompare(*itr, "PreSimulator") == 0)
+		{
+			m_FinishGens.push_back(new cFinishGenPreSimulator);
+		}
+		else if (NoCaseCompare(*itr, "Snow") == 0)
+		{
+			m_FinishGens.push_back(new cFinishGenSnow);
+		}
+		else if (NoCaseCompare(*itr, "SprinkleFoliage") == 0)
+		{
+			m_FinishGens.push_back(new cFinishGenSprinkleFoliage(Seed));
+		}
+		else if (NoCaseCompare(*itr, "WaterSprings") == 0)
+		{
+			m_FinishGens.push_back(new cFinishGenFluidSprings(Seed, E_BLOCK_WATER, a_IniFile, *m_World));
+		}
+	}  // for itr - Str[]
+}
+
+
+
+

src/Generating/ComposableGenerator.h

@@ -0,0 +1,181 @@
+
+// ComposableGenerator.h
+
+// Declares the cComposableGenerator class representing the chunk generator that takes the composition approach to generating chunks
+
+/*
+Generating works by composing several algorithms:
+Biome, TerrainHeight, TerrainComposition, Ores, Structures and SmallFoliage
+Each algorithm may be chosen from a pool of available algorithms in the same class and combined with others,
+based on user's preferences in the world.ini.
+See http://forum.mc-server.org/showthread.php?tid=409 for details.
+*/
+
+
+
+
+
+#pragma once
+
+#include "ChunkGenerator.h"
+#include "ChunkDesc.h"
+
+
+
+
+
+// fwd: Noise3DGenerator.h
+class cNoise3DComposable;
+
+// fwd: DistortedHeightmap.h
+class cDistortedHeightmap;
+
+
+
+
+
+/** The interface that a biome generator must implement
+A biome generator takes chunk coords on input and outputs an array of biome indices for that chunk on output.
+The output array is sequenced in the same way as the MapChunk packet's biome data.
+*/
+class cBiomeGen
+{
+public:
+	virtual ~cBiomeGen() {}  // Force a virtual destructor in descendants
+	
+	/// Generates biomes for the given chunk
+	virtual void GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap) = 0;
+	
+	/// Reads parameters from the ini file, prepares generator for use.
+	virtual void InitializeBiomeGen(cIniFile & a_IniFile) {}
+} ;
+
+
+
+
+
+/** The interface that a terrain height generator must implement
+A terrain height generator takes chunk coords on input and outputs an array of terrain heights for that chunk.
+The output array is sequenced in the same way as the BiomeGen's biome data.
+The generator may request biome information from the underlying BiomeGen, it may even request information for
+other chunks than the one it's currently generating (possibly neighbors - for averaging)
+*/
+class cTerrainHeightGen
+{
+public:
+	virtual ~cTerrainHeightGen() {}  // Force a virtual destructor in descendants
+	
+	/// Generates heightmap for the given chunk
+	virtual void GenHeightMap(int a_ChunkX, int a_ChunkZ, cChunkDef::HeightMap & a_HeightMap) = 0;
+	
+	/// Reads parameters from the ini file, prepares generator for use.
+	virtual void InitializeHeightGen(cIniFile & a_IniFile) {}
+} ;
+
+
+
+
+
+/** The interface that a terrain composition generator must implement
+Terrain composition takes chunk coords on input and outputs the blockdata for that entire chunk, along with
+the list of entities. It is supposed to make use of the underlying TerrainHeightGen and BiomeGen for that purpose,
+but it may request information for other chunks than the one it's currently generating from them.
+*/
+class cTerrainCompositionGen
+{
+public:
+	virtual ~cTerrainCompositionGen() {}  // Force a virtual destructor in descendants
+	
+	virtual void ComposeTerrain(cChunkDesc & a_ChunkDesc) = 0;
+	
+	/// Reads parameters from the ini file, prepares generator for use.
+	virtual void InitializeCompoGen(cIniFile & a_IniFile) {}
+} ;
+
+
+
+
+
+/** The interface that a structure generator must implement
+Structures are generated after the terrain composition took place. It should modify the blocktype data to account
+for whatever structures the generator is generating.
+Note that ores are considered structures too, at least from the interface point of view.
+Also note that a worldgenerator may contain multiple structure generators, one for each type of structure
+*/
+class cStructureGen
+{
+public:
+	virtual ~cStructureGen() {}  // Force a virtual destructor in descendants
+	
+	virtual void GenStructures(cChunkDesc & a_ChunkDesc) = 0;
+} ;
+
+typedef std::list<cStructureGen *> cStructureGenList;
+
+
+
+
+
+/** The interface that a finisher must implement
+Finisher implements small additions after all structures have been generated.
+*/
+class cFinishGen
+{
+public:
+	virtual ~cFinishGen() {}  // Force a virtual destructor in descendants
+	
+	virtual void GenFinish(cChunkDesc & a_ChunkDesc) = 0;
+} ;
+
+typedef std::list<cFinishGen *> cFinishGenList;
+
+
+
+
+
+class cComposableGenerator :
+	public cChunkGenerator::cGenerator
+{
+	typedef cChunkGenerator::cGenerator super;
+	
+public:
+	cComposableGenerator(cChunkGenerator & a_ChunkGenerator);
+	virtual ~cComposableGenerator();
+	
+	virtual void Initialize(cWorld * a_World, cIniFile & a_IniFile) override;
+	virtual void GenerateBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap) override;
+	virtual void DoGenerate(int a_ChunkX, int a_ChunkZ, cChunkDesc & a_ChunkDesc) override;
+
+protected:
+	// The generation composition:
+	cBiomeGen *              m_BiomeGen;
+	cTerrainHeightGen *      m_HeightGen;
+	cTerrainCompositionGen * m_CompositionGen;
+	cStructureGenList        m_StructureGens;
+	cFinishGenList           m_FinishGens;
+	
+	// Generators underlying the caches:
+	cBiomeGen *              m_UnderlyingBiomeGen;
+	cTerrainHeightGen *      m_UnderlyingHeightGen;
+	cTerrainCompositionGen * m_UnderlyingCompositionGen;
+	
+	
+	/// Reads the biome gen settings from the ini and initializes m_BiomeGen accordingly
+	void InitBiomeGen(cIniFile & a_IniFile);
+	
+	/// Reads the HeightGen settings from the ini and initializes m_HeightGen accordingly
+	void InitHeightGen(cIniFile & a_IniFile);
+	
+	/// Reads the CompositionGen settings from the ini and initializes m_CompositionGen accordingly
+	void InitCompositionGen(cIniFile & a_IniFile);
+	
+	/// Reads the structures to generate from the ini and initializes m_StructureGens accordingly
+	void InitStructureGens(cIniFile & a_IniFile);
+	
+	/// Reads the finishers from the ini and initializes m_FinishGens accordingly
+	void InitFinishGens(cIniFile & a_IniFile);
+} ;
+
+
+
+

src/Generating/DistortedHeightmap.cpp

@@ -0,0 +1,444 @@
+
+// DistortedHeightmap.cpp
+
+// Implements the cDistortedHeightmap class representing the height and composition generator capable of overhangs
+
+#include "Globals.h"
+
+#include "DistortedHeightmap.h"
+#include "../OSSupport/File.h"
+#include "../../iniFile/iniFile.h"
+#include "../LinearUpscale.h"
+
+
+
+
+
+/** This table assigns a relative maximum overhang size in each direction to biomes.
+Both numbers indicate a number which will multiply the noise value for each coord;
+this means that you can have different-sized overhangs in each direction.
+Usually you'd want to keep both numbers the same.
+The numbers are "relative", not absolute maximum; overhangs of a slightly larger size are possible
+due to the way that noise is calculated.
+*/
+const cDistortedHeightmap::sGenParam cDistortedHeightmap::m_GenParam[biNumBiomes] =
+{
+	/* Biome              |   AmpX | AmpZ */
+	/* biOcean            */ { 1.5f,  1.5f},
+	/* biPlains           */ { 0.5f,  0.5f},
+	/* biDesert           */ { 0.5f,  0.5f},
+	/* biExtremeHills     */ {16.0f, 16.0f},
+	/* biForest           */ { 3.0f,  3.0f},
+	/* biTaiga            */ { 1.5f,  1.5f},
+	
+	/* biSwampland        */ { 0.0f,  0.0f},
+	/* biRiver            */ { 0.0f,  0.0f},
+	/* biNether           */ { 0.0f,  0.0f},  // Unused, but must be here due to indexing
+	/* biSky              */ { 0.0f,  0.0f},  // Unused, but must be here due to indexing
+	/* biFrozenOcean      */ { 0.0f,  0.0f},
+	/* biFrozenRiver      */ { 0.0f,  0.0f},
+	/* biIcePlains        */ { 0.0f,  0.0f},
+	/* biIceMountains     */ { 8.0f,  8.0f},
+	/* biMushroomIsland   */ { 4.0f,  4.0f},
+	/* biMushroomShore    */ { 0.0f,  0.0f},
+	/* biBeach            */ { 0.0f,  0.0f},
+	/* biDesertHills      */ { 5.0f,  5.0f},
+	/* biForestHills      */ { 6.0f,  6.0f},
+	/* biTaigaHills       */ { 8.0f,  8.0f},
+	/* biExtremeHillsEdge */ { 7.0f,  7.0f},
+	/* biJungle           */ { 0.0f,  0.0f},
+	/* biJungleHills      */ { 8.0f,  8.0f},
+} ;
+
+
+
+
+
+cDistortedHeightmap::cDistortedHeightmap(int a_Seed, cBiomeGen & a_BiomeGen) :
+	m_NoiseDistortX(a_Seed + 1000),
+	m_NoiseDistortZ(a_Seed + 2000),
+	m_OceanFloorSelect(a_Seed + 3000),
+	m_BiomeGen(a_BiomeGen),
+	m_UnderlyingHeiGen(a_Seed, a_BiomeGen),
+	m_HeightGen(m_UnderlyingHeiGen, 64)
+{
+	m_NoiseDistortX.AddOctave((NOISE_DATATYPE)1,    (NOISE_DATATYPE)0.5);
+	m_NoiseDistortX.AddOctave((NOISE_DATATYPE)0.5,  (NOISE_DATATYPE)1);
+	m_NoiseDistortX.AddOctave((NOISE_DATATYPE)0.25, (NOISE_DATATYPE)2);
+
+	m_NoiseDistortZ.AddOctave((NOISE_DATATYPE)1,    (NOISE_DATATYPE)0.5);
+	m_NoiseDistortZ.AddOctave((NOISE_DATATYPE)0.5,  (NOISE_DATATYPE)1);
+	m_NoiseDistortZ.AddOctave((NOISE_DATATYPE)0.25, (NOISE_DATATYPE)2);
+}
+
+
+
+
+
+void cDistortedHeightmap::Initialize(cIniFile & a_IniFile)
+{
+	if (m_IsInitialized)
+	{
+		return;
+	}
+	
+	// Read the params from the INI file:
+	m_SeaLevel   =                 a_IniFile.GetValueSetI("Generator", "DistortedHeightmapSeaLevel",   62);
+	m_FrequencyX = (NOISE_DATATYPE)a_IniFile.GetValueSetF("Generator", "DistortedHeightmapFrequencyX", 10);
+	m_FrequencyY = (NOISE_DATATYPE)a_IniFile.GetValueSetF("Generator", "DistortedHeightmapFrequencyY", 10);
+	m_FrequencyZ = (NOISE_DATATYPE)a_IniFile.GetValueSetF("Generator", "DistortedHeightmapFrequencyZ", 10);
+
+	m_IsInitialized = true;
+}
+
+
+
+
+
+void cDistortedHeightmap::PrepareState(int a_ChunkX, int a_ChunkZ)
+{
+	if ((m_CurChunkX == a_ChunkX) && (m_CurChunkZ == a_ChunkZ))
+	{
+		return;
+	}
+	m_CurChunkX = a_ChunkX;
+	m_CurChunkZ = a_ChunkZ;
+	
+	
+	m_HeightGen.GenHeightMap(a_ChunkX, a_ChunkZ, m_CurChunkHeights);
+	UpdateDistortAmps();
+	GenerateHeightArray();
+}
+
+
+
+
+
+void cDistortedHeightmap::GenerateHeightArray(void)
+{
+	// Generate distortion noise:
+	NOISE_DATATYPE DistortNoiseX[DIM_X * DIM_Y * DIM_Z];
+	NOISE_DATATYPE DistortNoiseZ[DIM_X * DIM_Y * DIM_Z];
+	NOISE_DATATYPE Workspace[DIM_X * DIM_Y * DIM_Z];
+	NOISE_DATATYPE StartX = ((NOISE_DATATYPE)(m_CurChunkX * cChunkDef::Width)) / m_FrequencyX;
+	NOISE_DATATYPE EndX   = ((NOISE_DATATYPE)((m_CurChunkX + 1) * cChunkDef::Width - 1)) / m_FrequencyX;
+	NOISE_DATATYPE StartY = 0;
+	NOISE_DATATYPE EndY   = ((NOISE_DATATYPE)(257)) / m_FrequencyY;
+	NOISE_DATATYPE StartZ = ((NOISE_DATATYPE)(m_CurChunkZ * cChunkDef::Width)) / m_FrequencyZ;
+	NOISE_DATATYPE EndZ   = ((NOISE_DATATYPE)((m_CurChunkZ + 1) * cChunkDef::Width - 1)) / m_FrequencyZ;
+	
+	m_NoiseDistortX.Generate3D(DistortNoiseX, DIM_X, DIM_Y, DIM_Z, StartX, EndX, StartY, EndY, StartZ, EndZ, Workspace);
+	m_NoiseDistortZ.Generate3D(DistortNoiseZ, DIM_X, DIM_Y, DIM_Z, StartX, EndX, StartY, EndY, StartZ, EndZ, Workspace);
+
+	// The distorted heightmap, before linear upscaling
+	NOISE_DATATYPE DistHei[DIM_X * DIM_Y * DIM_Z];
+	
+	// Distort the heightmap using the distortion:
+	for (int z = 0; z < DIM_Z; z++)
+	{
+		int AmpIdx = z * DIM_X;
+		for (int y = 0; y < DIM_Y; y++)
+		{
+			int NoiseArrayIdx = z * DIM_X * DIM_Y + y * DIM_X;
+			for (int x = 0; x < DIM_X; x++)
+			{
+				NOISE_DATATYPE DistX = DistortNoiseX[NoiseArrayIdx + x] * m_DistortAmpX[AmpIdx + x];
+				NOISE_DATATYPE DistZ = DistortNoiseZ[NoiseArrayIdx + x] * m_DistortAmpZ[AmpIdx + x];
+				DistX += (NOISE_DATATYPE)(m_CurChunkX * cChunkDef::Width + x * INTERPOL_X);
+				DistZ += (NOISE_DATATYPE)(m_CurChunkZ * cChunkDef::Width + z * INTERPOL_Z);
+				// Adding 0.5 helps alleviate the interpolation artifacts
+				DistHei[NoiseArrayIdx + x] = (NOISE_DATATYPE)GetHeightmapAt(DistX, DistZ) + (NOISE_DATATYPE)0.5;
+			}
+		}
+	}
+	
+	// Upscale the distorted heightmap into full dimensions:
+	LinearUpscale3DArray(
+		DistHei, DIM_X, DIM_Y, DIM_Z,
+		m_DistortedHeightmap, INTERPOL_X, INTERPOL_Y, INTERPOL_Z
+	);
+
+	// DEBUG: Debug3DNoise(m_DistortedHeightmap, 17, 257, 17, Printf("DistortedHeightmap_%d_%d", m_CurChunkX, m_CurChunkZ));
+}
+
+
+
+
+
+void cDistortedHeightmap::GenHeightMap(int a_ChunkX, int a_ChunkZ, cChunkDef::HeightMap & a_HeightMap)
+{
+	PrepareState(a_ChunkX, a_ChunkZ);
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			int NoiseArrayIdx = x + 17 * 257 * z;
+			cChunkDef::SetHeight(a_HeightMap, x, z, m_SeaLevel - 1);
+			for (int y = cChunkDef::Height - 1; y > m_SeaLevel - 1; y--)
+			{
+				int HeightMapHeight = (int)m_DistortedHeightmap[NoiseArrayIdx + 17 * y];
+				if (y < HeightMapHeight)
+				{
+					cChunkDef::SetHeight(a_HeightMap, x, z, y);
+					break;
+				}
+			}  // for y
+		}  // for x
+	}  // for z
+}
+
+
+
+
+
+void cDistortedHeightmap::InitializeHeightGen(cIniFile & a_IniFile)
+{
+	Initialize(a_IniFile);
+}
+
+
+
+
+
+void cDistortedHeightmap::ComposeTerrain(cChunkDesc & a_ChunkDesc)
+{
+	// Frequencies for the ocean floor selecting noise:
+	NOISE_DATATYPE FrequencyX = 3;
+	NOISE_DATATYPE FrequencyZ = 3;
+
+	// Prepare the internal state for generating this chunk:
+	PrepareState(a_ChunkDesc.GetChunkX(), a_ChunkDesc.GetChunkZ());
+	
+	// Compose:
+	a_ChunkDesc.FillBlocks(E_BLOCK_AIR, 0);
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			int NoiseArrayIdx = x + 17 * 257 * z;
+			int LastAir = a_ChunkDesc.GetHeight(x, z) + 1;
+			bool HasHadWater = false;
+			for (int y = LastAir - 1; y > 0; y--)
+			{
+				int HeightMapHeight = (int)m_DistortedHeightmap[NoiseArrayIdx + 17 * y];
+
+				if (y >= HeightMapHeight)
+				{
+					// "air" part
+					LastAir = y;
+					if (y < m_SeaLevel)
+					{
+						a_ChunkDesc.SetBlockType(x, y, z, E_BLOCK_STATIONARY_WATER);
+						HasHadWater = true;
+					}
+					continue;
+				}
+				// "ground" part:
+				if (y < LastAir - 4)
+				{
+					a_ChunkDesc.SetBlockType(x, y, z, E_BLOCK_STONE);
+					continue;
+				}
+				if (HasHadWater)
+				{
+					// Decide between clay, sand and dirt
+					NOISE_DATATYPE NoiseX = ((NOISE_DATATYPE)(m_CurChunkX * cChunkDef::Width + x)) / FrequencyX;
+					NOISE_DATATYPE NoiseY = ((NOISE_DATATYPE)(m_CurChunkZ * cChunkDef::Width + z)) / FrequencyZ;
+					NOISE_DATATYPE Val = m_OceanFloorSelect.CubicNoise2D(NoiseX, NoiseY);
+					if (Val < -0.95)
+					{
+						// Clay:
+						switch (LastAir - y)
+						{
+							case 0:
+							case 1:
+							{
+								a_ChunkDesc.SetBlockType(x, y, z, E_BLOCK_CLAY);
+								break;
+							}
+							case 2:
+							case 3:
+							{
+								a_ChunkDesc.SetBlockType(x, y, z, E_BLOCK_SAND);
+								break;
+							}
+							case 4:
+							{
+								a_ChunkDesc.SetBlockType(x, y, z, E_BLOCK_SANDSTONE);
+								break;
+							}
+						}  // switch (floor depth)
+					}
+					else if (Val < 0)
+					{
+						a_ChunkDesc.SetBlockType(x, y, z, (y < LastAir - 3) ? E_BLOCK_SANDSTONE : E_BLOCK_SAND);
+					}
+					else
+					{
+						a_ChunkDesc.SetBlockType(x, y, z, E_BLOCK_DIRT);
+					}
+				}
+				else
+				{
+					switch (a_ChunkDesc.GetBiome(x, z))
+					{
+						case biOcean:
+						case biPlains:
+						case biExtremeHills:
+						case biForest:
+						case biTaiga:
+						case biSwampland:
+						case biRiver:
+						case biFrozenOcean:
+						case biFrozenRiver:
+						case biIcePlains:
+						case biIceMountains:
+						case biForestHills:
+						case biTaigaHills:
+						case biExtremeHillsEdge:
+						case biJungle:
+						case biJungleHills:
+						{
+							a_ChunkDesc.SetBlockType(x, y, z, (y == LastAir - 1) ? E_BLOCK_GRASS : E_BLOCK_DIRT);
+							break;
+						}
+						case biDesertHills:
+						case biDesert:
+						case biBeach:
+						{
+							a_ChunkDesc.SetBlockType(x, y, z, (y < LastAir - 3) ? E_BLOCK_SANDSTONE : E_BLOCK_SAND);
+							break;
+						}
+						case biMushroomIsland:
+						case biMushroomShore:
+						{
+							a_ChunkDesc.SetBlockType(x, y, z, (y == LastAir - 1) ? E_BLOCK_MYCELIUM : E_BLOCK_DIRT);
+							break;
+						}
+					}
+				}
+			}  // for y
+			a_ChunkDesc.SetBlockType(x, 0, z, E_BLOCK_BEDROCK);
+		}  // for x
+	}  // for z
+}
+
+
+
+
+
+void cDistortedHeightmap::InitializeCompoGen(cIniFile & a_IniFile)
+{
+	Initialize(a_IniFile);
+}
+
+
+
+
+
+int cDistortedHeightmap::GetHeightmapAt(NOISE_DATATYPE a_X, NOISE_DATATYPE a_Z)
+{
+	int ChunkX = (int)floor(a_X / (NOISE_DATATYPE)16);
+	int ChunkZ = (int)floor(a_Z / (NOISE_DATATYPE)16);
+	int RelX = (int)(a_X - (NOISE_DATATYPE)ChunkX * cChunkDef::Width);
+	int RelZ = (int)(a_Z - (NOISE_DATATYPE)ChunkZ * cChunkDef::Width);
+
+	// If we're withing the same chunk, return the pre-cached heightmap:
+	if ((ChunkX == m_CurChunkX) && (ChunkZ == m_CurChunkZ))
+	{
+		return cChunkDef::GetHeight(m_CurChunkHeights, RelX, RelZ);
+	}
+	
+	// Ask the cache:
+	HEIGHTTYPE res = 0;
+	if (m_HeightGen.GetHeightAt(ChunkX, ChunkZ, RelX, RelZ, res))
+	{
+		// The height was in the cache
+		return res;
+	}
+	
+	// The height is not in the cache, generate full heightmap and get it there:
+	cChunkDef::HeightMap Heightmap;
+	m_HeightGen.GenHeightMap(ChunkX, ChunkZ, Heightmap);
+	return cChunkDef::GetHeight(Heightmap, RelX, RelZ);
+}
+
+
+
+
+
+void cDistortedHeightmap::UpdateDistortAmps(void)
+{
+	BiomeNeighbors Biomes;
+	for (int z = -1; z <= 1; z++)
+	{
+		for (int x = -1; x <= 1; x++)
+		{
+			m_BiomeGen.GenBiomes(m_CurChunkX + x, m_CurChunkZ + z, Biomes[x + 1][z + 1]);
+		}  // for x
+	}  // for z
+
+	for (int z = 0; z < DIM_Z; z++)
+	{
+		for (int x = 0; x < DIM_Z; x++)
+		{
+			GetDistortAmpsAt(Biomes, x * INTERPOL_X, z * INTERPOL_Z, m_DistortAmpX[x + DIM_X * z], m_DistortAmpZ[x + DIM_X * z]);
+		}
+	}
+}	
+
+
+
+
+
+void cDistortedHeightmap::GetDistortAmpsAt(BiomeNeighbors & a_Neighbors, int a_RelX, int a_RelZ, NOISE_DATATYPE & a_DistortAmpX, NOISE_DATATYPE & a_DistortAmpZ)
+{
+	// Sum up how many biomes of each type there are in the neighborhood:
+	int BiomeCounts[biNumBiomes];
+	memset(BiomeCounts, 0, sizeof(BiomeCounts));
+	int Sum = 0;
+	for (int z = -8; z <= 8; z++)
+	{
+		int FinalZ = a_RelZ + z + cChunkDef::Width;
+		int IdxZ = FinalZ / cChunkDef::Width;
+		int ModZ = FinalZ % cChunkDef::Width;
+		int WeightZ = 9 - abs(z);
+		for (int x = -8; x <= 8; x++)
+		{
+			int FinalX = a_RelX + x + cChunkDef::Width;
+			int IdxX = FinalX / cChunkDef::Width;
+			int ModX = FinalX % cChunkDef::Width;
+			EMCSBiome Biome = cChunkDef::GetBiome(a_Neighbors[IdxX][IdxZ], ModX, ModZ);
+			if ((Biome < 0) || (Biome >= ARRAYCOUNT(BiomeCounts)))
+			{
+				continue;
+			}
+			int WeightX = 9 - abs(x);
+			BiomeCounts[Biome] += WeightX + WeightZ;
+			Sum += WeightX + WeightZ;
+		}  // for x
+	}  // for z
+
+	if (Sum <= 0)
+	{
+		// No known biome around? Weird. Return a bogus value:
+		ASSERT(!"cHeiGenBiomal: Biome sum failed, no known biome around");
+		a_DistortAmpX = 16;
+		a_DistortAmpZ = 16;
+	}
+
+	// For each biome type that has a nonzero count, calc its amps and add it:
+	NOISE_DATATYPE AmpX = 0;
+	NOISE_DATATYPE AmpZ = 0;
+	for (int i = 0; i < ARRAYCOUNT(BiomeCounts); i++)
+	{
+		AmpX += BiomeCounts[i] * m_GenParam[i].m_DistortAmpX;
+		AmpZ += BiomeCounts[i] * m_GenParam[i].m_DistortAmpZ;
+	}
+	a_DistortAmpX = AmpX / Sum;
+	a_DistortAmpZ = AmpZ / Sum;
+}
+
+
+
+

src/Generating/DistortedHeightmap.h

@@ -0,0 +1,108 @@
+
+// DistortedHeightmap.h
+
+// Declares the cDistortedHeightmap class representing the height and composition generator capable of overhangs
+
+
+
+
+
+#pragma once
+
+#include "ComposableGenerator.h"
+#include "HeiGen.h"
+#include "../Noise.h"
+
+
+
+
+
+#define NOISE_SIZE_Y (257 + 32)
+
+
+
+
+
+class cDistortedHeightmap :
+	public cTerrainHeightGen,
+	public cTerrainCompositionGen
+{
+public:
+	cDistortedHeightmap(int a_Seed, cBiomeGen & a_BiomeGen);
+	
+protected:
+	typedef cChunkDef::BiomeMap BiomeNeighbors[3][3];
+
+	// Linear upscaling step sizes, must be divisors of cChunkDef::Width and cChunkDef::Height, respectively:
+	static const int INTERPOL_X = 8;
+	static const int INTERPOL_Y = 4;
+	static const int INTERPOL_Z = 8;
+
+	// Linear upscaling buffer dimensions, calculated from the step sizes:
+	static const int DIM_X = 1 +  (17 / INTERPOL_X);
+	static const int DIM_Y = 1 + (257 / INTERPOL_Y);
+	static const int DIM_Z = 1 +  (17 / INTERPOL_Z);
+
+	cPerlinNoise m_NoiseDistortX;
+	cPerlinNoise m_NoiseDistortZ;
+	cNoise       m_OceanFloorSelect;  ///< Used for selecting between dirt and sand on the ocean floor
+
+	int m_SeaLevel;
+	NOISE_DATATYPE m_FrequencyX;
+	NOISE_DATATYPE m_FrequencyY;
+	NOISE_DATATYPE m_FrequencyZ;
+
+	int m_CurChunkX;
+	int m_CurChunkZ;
+	NOISE_DATATYPE m_DistortedHeightmap[17 * 257 * 17];
+
+	cBiomeGen &   m_BiomeGen;
+	cHeiGenBiomal m_UnderlyingHeiGen;  // This generator provides us with base heightmap (before distortion)
+	cHeiGenCache  m_HeightGen;         // Cache above m_UnderlyingHeiGen
+	
+	/// Heightmap for the current chunk, before distortion (from m_HeightGen). Used for optimization.
+	cChunkDef::HeightMap m_CurChunkHeights;
+	
+	// Per-biome terrain generator parameters:
+	struct sGenParam
+	{
+		NOISE_DATATYPE m_DistortAmpX;
+		NOISE_DATATYPE m_DistortAmpZ;
+	} ;
+	static const sGenParam m_GenParam[biNumBiomes];
+	
+	// Distortion amplitudes for each direction, before linear upscaling
+	NOISE_DATATYPE m_DistortAmpX[DIM_X * DIM_Z];
+	NOISE_DATATYPE m_DistortAmpZ[DIM_X * DIM_Z];
+	
+	/// True if Initialize() has been called. Used to initialize-once even with multiple init entrypoints (HeiGen / CompoGen)
+	bool m_IsInitialized;
+	
+
+	/// Unless the LastChunk coords are equal to coords given, prepares the internal state (noise arrays, heightmap)
+	void PrepareState(int a_ChunkX, int a_ChunkZ);
+	
+	/// Generates the m_DistortedHeightmap array for the current chunk
+	void GenerateHeightArray(void);
+	
+	/// Calculates the heightmap value (before distortion) at the specified (floating-point) coords
+	int GetHeightmapAt(NOISE_DATATYPE a_X, NOISE_DATATYPE a_Z);
+	
+	/// Updates m_DistortAmpX/Z[] based on m_CurChunkX and m_CurChunkZ
+	void UpdateDistortAmps(void);
+	
+	/// Calculates the X and Z distortion amplitudes based on the neighbors' biomes
+	void GetDistortAmpsAt(BiomeNeighbors & a_Neighbors, int a_RelX, int a_RelZ, NOISE_DATATYPE & a_DistortAmpX, NOISE_DATATYPE & a_DistortAmpZ);
+	
+	/// Reads the settings from the ini file. Skips reading if already initialized
+	void Initialize(cIniFile & a_IniFile);
+	
+	
+	// cTerrainHeightGen overrides:
+	virtual void GenHeightMap(int a_ChunkX, int a_ChunkZ, cChunkDef::HeightMap & a_HeightMap) override;
+	virtual void InitializeHeightGen(cIniFile & a_IniFile) override;
+
+	// cTerrainCompositionGen overrides:
+	virtual void ComposeTerrain(cChunkDesc & a_ChunkDesc) override;
+	virtual void InitializeCompoGen(cIniFile & a_IniFile) override;
+} ;

src/Generating/EndGen.cpp

@@ -0,0 +1,217 @@
+
+// EndGen.cpp
+
+// Implements the cEndGen class representing the generator for the End, both as a HeightGen and CompositionGen
+
+#include "Globals.h"
+#include "EndGen.h"
+#include "../../iniFile/iniFile.h"
+#include "../LinearUpscale.h"
+
+
+
+
+
+enum
+{
+	// Interpolation cell size:
+	INTERPOL_X = 4,
+	INTERPOL_Y = 4,
+	INTERPOL_Z = 4,
+	
+	// Size of chunk data, downscaled before interpolation:
+	DIM_X = 16  / INTERPOL_X + 1,
+	DIM_Y = 256 / INTERPOL_Y + 1,
+	DIM_Z = 16  / INTERPOL_Z + 1,
+} ;
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cEndGen:
+
+cEndGen::cEndGen(int a_Seed) :
+	m_Seed(a_Seed),
+	m_IslandSizeX(256),
+	m_IslandSizeY(96),
+	m_IslandSizeZ(256),
+	m_FrequencyX(80),
+	m_FrequencyY(80),
+	m_FrequencyZ(80)
+{
+	m_Perlin.AddOctave(1, 1);
+	m_Perlin.AddOctave(2, 0.5);
+	m_Perlin.AddOctave(4, 0.25);
+}
+
+
+
+
+
+void cEndGen::Initialize(cIniFile & a_IniFile)
+{
+	m_IslandSizeX = a_IniFile.GetValueSetI("Generator", "EndGenIslandSizeX", m_IslandSizeX);
+	m_IslandSizeY = a_IniFile.GetValueSetI("Generator", "EndGenIslandSizeY", m_IslandSizeY);
+	m_IslandSizeZ = a_IniFile.GetValueSetI("Generator", "EndGenIslandSizeZ", m_IslandSizeZ);
+
+	m_FrequencyX = (NOISE_DATATYPE)a_IniFile.GetValueSetF("Generator", "EndGenFrequencyX", m_FrequencyX);
+	m_FrequencyY = (NOISE_DATATYPE)a_IniFile.GetValueSetF("Generator", "EndGenFrequencyY", m_FrequencyY);
+	m_FrequencyZ = (NOISE_DATATYPE)a_IniFile.GetValueSetF("Generator", "EndGenFrequencyZ", m_FrequencyZ);
+	
+	// Recalculate the min and max chunk coords of the island
+	m_MaxChunkX = (m_IslandSizeX + cChunkDef::Width - 1) / cChunkDef::Width;
+	m_MinChunkX = -m_MaxChunkX;
+	m_MaxChunkZ = (m_IslandSizeZ + cChunkDef::Width - 1) / cChunkDef::Width;
+	m_MinChunkZ = -m_MaxChunkZ;
+}
+
+
+
+
+
+/// Unless the LastChunk coords are equal to coords given, prepares the internal state (noise array)
+void cEndGen::PrepareState(int a_ChunkX, int a_ChunkZ)
+{
+	ASSERT(!IsChunkOutsideRange(a_ChunkX, a_ChunkZ));  // Should be filtered before calling this function
+	
+	if ((m_LastChunkX == a_ChunkX) && (m_LastChunkZ == a_ChunkZ))
+	{
+		return;
+	}
+	
+	m_LastChunkX = a_ChunkX;
+	m_LastChunkZ = a_ChunkZ;
+	
+	GenerateNoiseArray();
+}
+
+
+
+
+
+/// Generates the m_NoiseArray array for the current chunk
+void cEndGen::GenerateNoiseArray(void)
+{
+	NOISE_DATATYPE NoiseData[DIM_X * DIM_Y * DIM_Z];  // [x + DIM_X * z + DIM_X * DIM_Z * y]
+	NOISE_DATATYPE Workspace[DIM_X * DIM_Y * DIM_Z];  // [x + DIM_X * z + DIM_X * DIM_Z * y]
+	
+	// Generate the downscaled noise:
+	NOISE_DATATYPE StartX = ((NOISE_DATATYPE)(m_LastChunkX       * cChunkDef::Width)) / m_FrequencyX;
+	NOISE_DATATYPE EndX   = ((NOISE_DATATYPE)((m_LastChunkX + 1) * cChunkDef::Width)) / m_FrequencyX;
+	NOISE_DATATYPE StartZ = ((NOISE_DATATYPE)(m_LastChunkZ       * cChunkDef::Width)) / m_FrequencyZ;
+	NOISE_DATATYPE EndZ   = ((NOISE_DATATYPE)((m_LastChunkZ + 1) * cChunkDef::Width)) / m_FrequencyZ;
+	NOISE_DATATYPE StartY = 0;
+	NOISE_DATATYPE EndY   = ((NOISE_DATATYPE)257) / m_FrequencyY;
+	m_Perlin.Generate3D(NoiseData, DIM_X, DIM_Z, DIM_Y, StartX, EndX, StartZ, EndZ, StartY, EndY, Workspace);
+	
+	// Add distance:
+	int idx = 0;
+	for (int y = 0; y < DIM_Y; y++)
+	{
+		NOISE_DATATYPE ValY = (NOISE_DATATYPE)(2 * INTERPOL_Y * y - m_IslandSizeY) / m_IslandSizeY;
+		ValY = ValY * ValY;
+		for (int z = 0; z < DIM_Z; z++)
+		{
+			NOISE_DATATYPE ValZ = (NOISE_DATATYPE)(m_LastChunkZ * cChunkDef::Width + (z * cChunkDef::Width / (DIM_Z - 1))) / m_IslandSizeZ;
+			ValZ = ValZ * ValZ;
+			for (int x = 0; x < DIM_X; x++)
+			{
+				// NOISE_DATATYPE ValX = StartX + (EndX - StartX) * x / (DIM_X - 1);
+				NOISE_DATATYPE ValX = (NOISE_DATATYPE)(m_LastChunkX * cChunkDef::Width + (x * cChunkDef::Width / (DIM_X - 1))) / m_IslandSizeX;
+				ValX = ValX * ValX;
+				NoiseData[idx++] += ValX + ValZ + ValY;
+			}  // for x
+		}  // for z
+	}  // for y
+	
+	// Upscale into real chunk size:
+	LinearUpscale3DArray(NoiseData, DIM_X, DIM_Z, DIM_Y, m_NoiseArray, INTERPOL_X, INTERPOL_Z, INTERPOL_Y);
+}
+
+
+
+
+	
+/// Returns true if the chunk is outside of the island's dimensions
+bool cEndGen::IsChunkOutsideRange(int a_ChunkX, int a_ChunkZ)
+{
+	return (
+		(a_ChunkX < m_MinChunkX) || (a_ChunkX > m_MaxChunkX) ||
+		(a_ChunkZ < m_MinChunkZ) || (a_ChunkZ > m_MaxChunkZ)
+	);		
+}
+
+
+
+
+
+void cEndGen::GenHeightMap(int a_ChunkX, int a_ChunkZ, cChunkDef::HeightMap & a_HeightMap)
+{
+	if (IsChunkOutsideRange(a_ChunkX, a_ChunkZ))
+	{
+		for (int i = 0; i < ARRAYCOUNT(a_HeightMap); i++)
+		{
+			a_HeightMap[i] = 0;
+		}
+		return;
+	}
+	
+	PrepareState(a_ChunkX, a_ChunkZ);
+	
+	int MaxY = std::min((int)(1.75 * m_IslandSizeY + 1), cChunkDef::Height - 1);
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			cChunkDef::SetHeight(a_HeightMap, x, z, MaxY);
+			for (int y = MaxY; y > 0; y--)
+			{
+				if (m_NoiseArray[y * 17 * 17 + z * 17 + x] <= 0)
+				{
+					cChunkDef::SetHeight(a_HeightMap, x, z, y);
+					break;
+				}
+			}  // for y
+		}  // for x
+	}  // for z
+}
+
+
+
+
+
+void cEndGen::ComposeTerrain(cChunkDesc & a_ChunkDesc)
+{
+	if (IsChunkOutsideRange(a_ChunkDesc.GetChunkX(), a_ChunkDesc.GetChunkZ()))
+	{
+		a_ChunkDesc.FillBlocks(E_BLOCK_AIR, 0);
+		return;
+	}
+	
+	PrepareState(a_ChunkDesc.GetChunkX(), a_ChunkDesc.GetChunkZ());
+	
+	int MaxY = std::min((int)(1.75 * m_IslandSizeY + 1), cChunkDef::Height - 1);
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			for (int y = MaxY; y > 0; y--)
+			{
+				if (m_NoiseArray[y * 17 * 17 + z * 17 + x] <= 0)
+				{
+					a_ChunkDesc.SetBlockTypeMeta(x, y, z, E_BLOCK_END_STONE, 0);
+				}
+				else
+				{
+					a_ChunkDesc.SetBlockTypeMeta(x, y, z, E_BLOCK_AIR, 0);
+				}
+			}  // for y
+		}  // for x
+	}  // for z
+}
+
+
+
+

src/Generating/EndGen.h

@@ -0,0 +1,69 @@
+
+// EndGen.h
+
+// Declares the cEndGen class representing the generator for the End, both as a HeightGen and CompositionGen
+
+
+
+
+
+#pragma once
+
+#include "ComposableGenerator.h"
+#include "../Noise.h"
+
+
+
+
+
+class cEndGen :
+	public cTerrainHeightGen,
+	public cTerrainCompositionGen
+{
+public:
+	cEndGen(int a_Seed);
+	
+	void Initialize(cIniFile & a_IniFile);
+	
+protected:
+
+	/// Seed for the noise
+	int m_Seed;
+	
+	/// The Perlin noise used for generating
+	cPerlinNoise m_Perlin;
+
+	// XYZ size of the "island", in blocks:
+	int m_IslandSizeX;
+	int m_IslandSizeY;
+	int m_IslandSizeZ;
+	
+	// XYZ Frequencies of the noise functions:
+	NOISE_DATATYPE m_FrequencyX;
+	NOISE_DATATYPE m_FrequencyY;
+	NOISE_DATATYPE m_FrequencyZ;
+	
+	// Minimum and maximum chunk coords for chunks inside the island area. Chunks outside won't get calculated at all
+	int m_MinChunkX, m_MaxChunkX;
+	int m_MinChunkZ, m_MaxChunkZ;
+	
+	// Noise array for the last chunk (in the noise range)
+	int m_LastChunkX;
+	int m_LastChunkZ;
+	NOISE_DATATYPE m_NoiseArray[17 * 17 * 257];  // x + 17 * z + 17 * 17 * y
+	
+	/// Unless the LastChunk coords are equal to coords given, prepares the internal state (noise array)
+	void PrepareState(int a_ChunkX, int a_ChunkZ);
+	
+	/// Generates the m_NoiseArray array for the current chunk
+	void GenerateNoiseArray(void);
+	
+	/// Returns true if the chunk is outside of the island's dimensions
+	bool IsChunkOutsideRange(int a_ChunkX, int a_ChunkZ);
+		
+	// cTerrainHeightGen overrides:
+	virtual void GenHeightMap(int a_ChunkX, int a_ChunkZ, cChunkDef::HeightMap & a_HeightMap) override;
+
+	// cTerrainCompositionGen overrides:
+	virtual void ComposeTerrain(cChunkDesc & a_ChunkDesc) override;
+} ;

src/Generating/FinishGen.cpp

@@ -0,0 +1,664 @@
+
+// FinishGen.cpp
+
+/* Implements the various finishing generators:
+	- cFinishGenSnow
+	- cFinishGenIce
+	- cFinishGenSprinkleFoliage
+*/
+
+#include "Globals.h"
+
+#include "FinishGen.h"
+#include "../Noise.h"
+#include "../BlockID.h"
+#include "../Simulator/FluidSimulator.h"  // for cFluidSimulator::CanWashAway()
+#include "../World.h"
+
+
+
+
+
+#define DEF_NETHER_WATER_SPRINGS    "0, 1; 255, 1"
+#define DEF_NETHER_LAVA_SPRINGS     "0, 0; 30, 0; 31, 50; 120, 50; 127, 0"
+#define DEF_OVERWORLD_WATER_SPRINGS "0, 0; 10, 10; 11, 75; 16, 83; 20, 83; 24, 78; 32, 62; 40, 40; 44, 15; 48, 7; 56, 2; 64, 1; 255, 0"
+#define DEF_OVERWORLD_LAVA_SPRINGS  "0, 0; 10, 5; 11, 45; 48, 2; 64, 1; 255, 0"
+#define DEF_END_WATER_SPRINGS       "0, 1; 255, 1"
+#define DEF_END_LAVA_SPRINGS        "0, 1; 255, 1"
+
+
+
+
+
+static inline bool IsWater(BLOCKTYPE a_BlockType)
+{
+	return (a_BlockType == E_BLOCK_STATIONARY_WATER) || (a_BlockType == E_BLOCK_WATER);
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cFinishGenSprinkleFoliage:
+
+bool cFinishGenSprinkleFoliage::TryAddSugarcane(cChunkDesc & a_ChunkDesc, int a_RelX, int a_RelY, int a_RelZ)
+{
+	// We'll be doing comparison to neighbors, so require the coords to be 1 block away from the chunk edges:
+	if (
+		(a_RelX < 1) || (a_RelX >= cChunkDef::Width  - 1) ||
+		(a_RelY < 1) || (a_RelY >= cChunkDef::Height - 2) ||
+		(a_RelZ < 1) || (a_RelZ >= cChunkDef::Width  - 1)
+	)
+	{
+		return false;
+	}
+
+	// Only allow dirt, grass or sand below sugarcane:
+	switch (a_ChunkDesc.GetBlockType(a_RelX, a_RelY, a_RelZ))
+	{
+		case E_BLOCK_DIRT:
+		case E_BLOCK_GRASS:
+		case E_BLOCK_SAND:
+		{
+			break;
+		}
+		default:
+		{
+			return false;
+		}
+	}
+
+	// Water is required next to the block below the sugarcane:
+	if (
+		!IsWater(a_ChunkDesc.GetBlockType(a_RelX - 1, a_RelY, a_RelZ)) &&
+		!IsWater(a_ChunkDesc.GetBlockType(a_RelX + 1, a_RelY, a_RelZ)) &&
+		!IsWater(a_ChunkDesc.GetBlockType(a_RelX    , a_RelY, a_RelZ - 1)) &&
+		!IsWater(a_ChunkDesc.GetBlockType(a_RelX    , a_RelY, a_RelZ + 1))
+	)
+	{
+		return false;
+	}
+	
+	// All conditions met, place a sugarcane here:
+	a_ChunkDesc.SetBlockType(a_RelX, a_RelY + 1, a_RelZ, E_BLOCK_SUGARCANE);
+	return true;
+}
+
+
+
+
+
+void cFinishGenSprinkleFoliage::GenFinish(cChunkDesc & a_ChunkDesc)
+{
+	// Generate small foliage (1-block):
+	
+	// TODO: Update heightmap with 1-block-tall foliage
+	for (int z = 0; z < cChunkDef::Width; z++) 
+	{
+		int BlockZ = a_ChunkDesc.GetChunkZ() * cChunkDef::Width + z;
+		const float zz = (float)BlockZ;
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			int BlockX = a_ChunkDesc.GetChunkX() * cChunkDef::Width + x;
+			if (((m_Noise.IntNoise2DInt(BlockX, BlockZ) / 8) % 128) < 124)
+			{
+				continue;
+			}
+			int Top = a_ChunkDesc.GetHeight(x, z);
+			if (Top > 250)
+			{
+				// Nothing grows above Y=250
+				continue;
+			}
+			if (a_ChunkDesc.GetBlockType(x, Top + 1, z) != E_BLOCK_AIR)
+			{
+				// Space already taken by something else, don't grow here
+				// WEIRD, since we're using heightmap, so there should NOT be anything above it
+				continue;
+			}
+			
+			const float xx = (float)BlockX;
+			float val1 = m_Noise.CubicNoise2D(xx * 0.1f,  zz * 0.1f );
+			float val2 = m_Noise.CubicNoise2D(xx * 0.01f, zz * 0.01f );
+			switch (a_ChunkDesc.GetBlockType(x, Top, z))
+			{
+				case E_BLOCK_GRASS:
+				{
+					float val3 = m_Noise.CubicNoise2D(xx * 0.01f + 10, zz * 0.01f + 10 );
+					float val4 = m_Noise.CubicNoise2D(xx * 0.05f + 20, zz * 0.05f + 20 );
+					if (val1 + val2 > 0.2f)
+					{
+						a_ChunkDesc.SetBlockType(x, ++Top, z, E_BLOCK_YELLOW_FLOWER);
+					}
+					else if (val2 + val3 > 0.2f)
+					{
+						a_ChunkDesc.SetBlockType(x, ++Top, z, E_BLOCK_RED_ROSE);
+					}
+					else if (val3 + val4 > 0.2f)
+					{
+						a_ChunkDesc.SetBlockType(x, ++Top, z, E_BLOCK_RED_MUSHROOM);
+					}
+					else if (val1 + val4 > 0.2f)
+					{
+						a_ChunkDesc.SetBlockType(x, ++Top, z, E_BLOCK_BROWN_MUSHROOM);
+					}
+					else if (val1 + val2 + val3 + val4 < -0.1)
+					{
+						a_ChunkDesc.SetBlockTypeMeta(x, ++Top, z, E_BLOCK_TALL_GRASS, E_META_TALL_GRASS_GRASS);
+					}
+					else if (TryAddSugarcane(a_ChunkDesc, x, Top, z))
+					{
+						++Top;
+					}
+					else if ((val1 > 0.5) && (val2 < -0.5))
+					{
+						a_ChunkDesc.SetBlockTypeMeta(x, ++Top, z, E_BLOCK_PUMPKIN, (int)(val3 * 8) % 4);
+					}
+					break;
+				}  // case E_BLOCK_GRASS
+				
+				case E_BLOCK_SAND:
+				{
+					int y = Top + 1;
+					if (
+						(x > 0) && (x < cChunkDef::Width - 1) &&
+						(z > 0) && (z < cChunkDef::Width - 1) &&
+						(val1 + val2 > 0.5f) &&
+						(a_ChunkDesc.GetBlockType(x + 1, y, z)     == E_BLOCK_AIR) &&
+						(a_ChunkDesc.GetBlockType(x - 1, y, z)     == E_BLOCK_AIR) &&
+						(a_ChunkDesc.GetBlockType(x,     y, z + 1) == E_BLOCK_AIR) &&
+						(a_ChunkDesc.GetBlockType(x,     y, z - 1) == E_BLOCK_AIR)
+					)
+					{
+						a_ChunkDesc.SetBlockType(x, ++Top, z, E_BLOCK_CACTUS);
+					}
+					else if (TryAddSugarcane(a_ChunkDesc, x, Top, z))
+					{
+						++Top;
+					}
+					break;
+				}
+			}  // switch (TopBlock)
+			a_ChunkDesc.SetHeight(x, z, Top);
+		}  // for y
+	}  // for z
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cFinishGenSnow:
+
+void cFinishGenSnow::GenFinish(cChunkDesc & a_ChunkDesc)
+{
+	// Add a snow block in snowy biomes onto blocks that can be snowed over
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			switch (a_ChunkDesc.GetBiome(x, z))
+			{
+				case biIcePlains:
+				case biIceMountains:
+				case biTaiga:
+				case biTaigaHills:
+				case biFrozenRiver:
+				case biFrozenOcean:
+				{
+					int Height = a_ChunkDesc.GetHeight(x, z);
+					if (g_BlockIsSnowable[a_ChunkDesc.GetBlockType(x, Height, z)])
+					{
+						a_ChunkDesc.SetBlockType(x, Height + 1, z, E_BLOCK_SNOW);
+						a_ChunkDesc.SetHeight(x, z, Height + 1);
+					}
+					break;
+				}
+			}
+		}
+	}  // for z
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cFinishGenIce:
+
+void cFinishGenIce::GenFinish(cChunkDesc & a_ChunkDesc)
+{
+	// Turn surface water into ice in icy biomes
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			switch (a_ChunkDesc.GetBiome(x, z))
+			{
+				case biIcePlains:
+				case biIceMountains:
+				case biTaiga:
+				case biTaigaHills:
+				case biFrozenRiver:
+				case biFrozenOcean:
+				{
+					int Height = a_ChunkDesc.GetHeight(x, z);
+					switch (a_ChunkDesc.GetBlockType(x, Height, z))
+					{
+						case E_BLOCK_WATER:
+						case E_BLOCK_STATIONARY_WATER:
+						{
+							a_ChunkDesc.SetBlockType(x, Height, z, E_BLOCK_ICE);
+							break;
+						}
+					}
+					break;
+				}
+			}
+		}
+	}  // for z
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cFinishGenLilypads:
+
+int cFinishGenSingleBiomeSingleTopBlock::GetNumToGen(const cChunkDef::BiomeMap & a_BiomeMap)
+{
+	int res = 0;
+	for (int i = 0; i < ARRAYCOUNT(a_BiomeMap); i++)
+	{
+		if (a_BiomeMap[i] == m_Biome)
+		{
+			res++;
+		}
+	}  // for i - a_BiomeMap[]
+	return m_Amount * res / 256;
+}
+
+
+
+
+
+void cFinishGenSingleBiomeSingleTopBlock::GenFinish(cChunkDesc & a_ChunkDesc)
+{
+	// Add Lilypads on top of water surface in Swampland
+
+	int NumToGen = GetNumToGen(a_ChunkDesc.GetBiomeMap());
+	int ChunkX = a_ChunkDesc.GetChunkX();
+	int ChunkZ = a_ChunkDesc.GetChunkZ();
+	for (int i = 0; i < NumToGen; i++)
+	{
+		int x = (m_Noise.IntNoise3DInt(ChunkX + ChunkZ, ChunkZ, i) / 13) % cChunkDef::Width;
+		int z = (m_Noise.IntNoise3DInt(ChunkX - ChunkZ, i, ChunkZ) / 11) % cChunkDef::Width;
+
+		// Place the block at {x, z} if possible:
+		if (a_ChunkDesc.GetBiome(x, z) != m_Biome)
+		{
+			// Incorrect biome
+			continue;
+		}
+		int Height = a_ChunkDesc.GetHeight(x, z);
+		if (Height >= cChunkDef::Height)
+		{
+			// Too high up
+			continue;
+		}
+		if (a_ChunkDesc.GetBlockType(x, Height + 1, z) != E_BLOCK_AIR)
+		{
+			// Not an empty block
+			continue;
+		}
+		BLOCKTYPE BlockBelow = a_ChunkDesc.GetBlockType(x, Height, z);
+		if ((BlockBelow == m_AllowedBelow1) || (BlockBelow == m_AllowedBelow2))
+		{
+			a_ChunkDesc.SetBlockType(x, Height + 1, z, m_BlockType);
+			a_ChunkDesc.SetHeight(x, z, Height + 1);
+		}
+	}  // for i
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cFinishGenBottomLava:
+
+void cFinishGenBottomLava::GenFinish(cChunkDesc & a_ChunkDesc)
+{
+	cChunkDef::BlockTypes & BlockTypes = a_ChunkDesc.GetBlockTypes();
+	for (int y = m_Level; y > 0; y--)
+	{
+		for (int z = 0; z < cChunkDef::Width; z++) for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			int Index = cChunkDef::MakeIndexNoCheck(x, y, z);
+			if (BlockTypes[Index] == E_BLOCK_AIR)
+			{
+				BlockTypes[Index] = E_BLOCK_STATIONARY_LAVA;
+			}
+		}  // for x, for z
+	}  // for y
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cFinishGenPreSimulator:
+
+cFinishGenPreSimulator::cFinishGenPreSimulator(void)
+{
+	// Nothing needed yet
+}
+
+
+
+
+
+void cFinishGenPreSimulator::GenFinish(cChunkDesc & a_ChunkDesc)
+{
+	CollapseSandGravel(a_ChunkDesc.GetBlockTypes(), a_ChunkDesc.GetHeightMap());
+	StationarizeFluid(a_ChunkDesc.GetBlockTypes(), a_ChunkDesc.GetHeightMap(), E_BLOCK_WATER, E_BLOCK_STATIONARY_WATER);
+	StationarizeFluid(a_ChunkDesc.GetBlockTypes(), a_ChunkDesc.GetHeightMap(), E_BLOCK_LAVA,  E_BLOCK_STATIONARY_LAVA);
+	// TODO: other operations
+}
+
+
+
+
+
+void cFinishGenPreSimulator::CollapseSandGravel(
+	cChunkDef::BlockTypes & a_BlockTypes,    // Block types to read and change
+	cChunkDef::HeightMap & a_HeightMap       // Height map to update by the current data
+)
+{
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			int LastY = -1;
+			int HeightY = 0;
+			for (int y = 0; y < cChunkDef::Height; y++)
+			{
+				BLOCKTYPE Block = cChunkDef::GetBlock(a_BlockTypes, x, y, z);
+				switch (Block)
+				{
+					default:
+					{
+						// Set the last block onto which stuff can fall to this height:
+						LastY = y;
+						HeightY = y;
+						break;
+					}
+					case E_BLOCK_AIR:
+					{
+						// Do nothing
+						break;
+					}
+					case E_BLOCK_FIRE:
+					case E_BLOCK_WATER:
+					case E_BLOCK_STATIONARY_WATER:
+					case E_BLOCK_LAVA:
+					case E_BLOCK_STATIONARY_LAVA:
+					{
+						// Do nothing, only remember this height as potentially highest
+						HeightY = y;
+						break;
+					}
+					case E_BLOCK_SAND:
+					case E_BLOCK_GRAVEL:
+					{
+						if (LastY < y - 1)
+						{
+							cChunkDef::SetBlock(a_BlockTypes, x, LastY + 1, z, Block);
+							cChunkDef::SetBlock(a_BlockTypes, x, y, z, E_BLOCK_AIR);
+						}
+						LastY++;
+						if (LastY > HeightY)
+						{
+							HeightY = LastY;
+						}
+						break;
+					}
+				}  // switch (GetBlock)
+			}  // for y
+			cChunkDef::SetHeight(a_HeightMap, x, z, HeightY);
+		}  // for x
+	}  // for z
+}
+
+
+
+
+
+void cFinishGenPreSimulator::StationarizeFluid(
+	cChunkDef::BlockTypes & a_BlockTypes,    // Block types to read and change
+	cChunkDef::HeightMap & a_HeightMap,      // Height map to read
+	BLOCKTYPE a_Fluid,
+	BLOCKTYPE a_StationaryFluid
+)
+{
+	// Turn fluid in the middle to stationary, unless it has air or washable block next to it:
+	for (int z = 1; z < cChunkDef::Width - 1; z++)
+	{
+		for (int x = 1; x < cChunkDef::Width - 1; x++)
+		{
+			for (int y = cChunkDef::GetHeight(a_HeightMap, x, z); y >= 0; y--)
+			{
+				BLOCKTYPE Block = cChunkDef::GetBlock(a_BlockTypes, x, y, z);
+				if ((Block != a_Fluid) && (Block != a_StationaryFluid))
+				{
+					continue;
+				}
+				static const struct
+				{
+					int x, y, z;
+				} Coords[] =
+				{
+					{1, 0, 0},
+					{-1, 0, 0},
+					{0, 0, 1},
+					{0, 0, -1},
+					{0, -1, 0}
+				} ;
+				BLOCKTYPE BlockToSet = a_StationaryFluid;  // By default, don't simulate this block
+				for (int i = 0; i < ARRAYCOUNT(Coords); i++)
+				{
+					if ((y == 0) && (Coords[i].y < 0))
+					{
+						continue;
+					}
+					BLOCKTYPE Neighbor = cChunkDef::GetBlock(a_BlockTypes, x + Coords[i].x, y + Coords[i].y, z + Coords[i].z);
+					if ((Neighbor == E_BLOCK_AIR) || cFluidSimulator::CanWashAway(Neighbor))
+					{
+						// There is an air / washable neighbor, simulate this block
+						BlockToSet = a_Fluid;
+						break;
+					}
+				}  // for i - Coords[]
+				cChunkDef::SetBlock(a_BlockTypes, x, y, z, BlockToSet);
+			}  // for y
+		}  // for x
+	}  // for z
+	
+	// Turn fluid at the chunk edges into non-stationary fluid:
+	for (int y = 0; y < cChunkDef::Height; y++)
+	{
+		for (int i = 0; i < cChunkDef::Width; i++)  // i stands for both x and z here
+		{
+			if (cChunkDef::GetBlock(a_BlockTypes, 0, y, i) == a_StationaryFluid)
+			{
+				cChunkDef::SetBlock(a_BlockTypes, 0, y, i, a_Fluid);
+			}
+			if (cChunkDef::GetBlock(a_BlockTypes, i, y, 0) == a_StationaryFluid)
+			{
+				cChunkDef::SetBlock(a_BlockTypes, i, y, 0, a_Fluid);
+			}
+			if (cChunkDef::GetBlock(a_BlockTypes, cChunkDef::Width - 1, y, i) == a_StationaryFluid)
+			{
+				cChunkDef::SetBlock(a_BlockTypes, cChunkDef::Width - 1, y, i, a_Fluid);
+			}
+			if (cChunkDef::GetBlock(a_BlockTypes, i, y, cChunkDef::Width - 1) == a_StationaryFluid)
+			{
+				cChunkDef::SetBlock(a_BlockTypes, i, y, cChunkDef::Width - 1, a_Fluid);
+			}
+		}
+	}
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cFinishGenFluidSprings:
+
+cFinishGenFluidSprings::cFinishGenFluidSprings(int a_Seed, BLOCKTYPE a_Fluid, cIniFile & a_IniFile, const cWorld & a_World) :
+	m_Noise(a_Seed + a_Fluid * 100),  // Need to take fluid into account, otherwise water and lava springs generate next to each other
+	m_HeightDistribution(255),
+	m_Fluid(a_Fluid)
+{
+	bool IsWater = (a_Fluid == E_BLOCK_WATER);
+	AString SectionName = IsWater ? "WaterSprings" : "LavaSprings";
+	AString DefaultHeightDistribution;
+	int DefaultChance;
+	switch (a_World.GetDimension())
+	{
+		case dimNether:
+		{
+			DefaultHeightDistribution = IsWater ? DEF_NETHER_WATER_SPRINGS : DEF_NETHER_LAVA_SPRINGS;
+			DefaultChance = IsWater ? 0 : 15;
+			break;
+		}
+		case dimOverworld:
+		{
+			DefaultHeightDistribution = IsWater ? DEF_OVERWORLD_WATER_SPRINGS : DEF_OVERWORLD_LAVA_SPRINGS;
+			DefaultChance = IsWater ? 24 : 9;
+			break;
+		}
+		case dimEnd:
+		{
+			DefaultHeightDistribution = IsWater ? DEF_END_WATER_SPRINGS : DEF_END_LAVA_SPRINGS;
+			DefaultChance = 0;
+			break;
+		}
+		default:
+		{
+			ASSERT(!"Unhandled world dimension");
+			break;
+		}
+	}  // switch (dimension)
+	AString HeightDistribution = a_IniFile.GetValueSet(SectionName, "HeightDistribution", DefaultHeightDistribution);
+	if (!m_HeightDistribution.SetDefString(HeightDistribution) || (m_HeightDistribution.GetSum() <= 0))
+	{
+		LOGWARNING("[%sSprings]: HeightDistribution is invalid, using the default of \"%s\".", 
+			(a_Fluid == E_BLOCK_WATER) ? "Water" : "Lava",
+			DefaultHeightDistribution.c_str()
+		);
+		m_HeightDistribution.SetDefString(DefaultHeightDistribution);
+	}
+	m_Chance = a_IniFile.GetValueSetI(SectionName, "Chance", DefaultChance);
+}
+
+
+
+
+
+void cFinishGenFluidSprings::GenFinish(cChunkDesc & a_ChunkDesc)
+{
+	int ChanceRnd = (m_Noise.IntNoise3DInt(128 * a_ChunkDesc.GetChunkX(), 512, 256 * a_ChunkDesc.GetChunkZ()) / 13) % 100;
+	if (ChanceRnd > m_Chance)
+	{
+		// Not in this chunk
+		return;
+	}
+	
+	// Get the height at which to try:
+	int Height = m_Noise.IntNoise3DInt(128 * a_ChunkDesc.GetChunkX(), 1024, 256 * a_ChunkDesc.GetChunkZ()) / 11;
+	Height %= m_HeightDistribution.GetSum();
+	Height = m_HeightDistribution.MapValue(Height);
+	
+	// Try adding the spring at the height, if unsuccessful, move lower:
+	for (int y = Height; y > 1; y--)
+	{
+		// TODO: randomize the order in which the coords are being checked
+		for (int z = 1; z < cChunkDef::Width - 1; z++)
+		{
+			for (int x = 1; x < cChunkDef::Width - 1; x++)
+			{
+				switch (a_ChunkDesc.GetBlockType(x, y, z))
+				{
+					case E_BLOCK_NETHERRACK:
+					case E_BLOCK_STONE:
+					{
+						if (TryPlaceSpring(a_ChunkDesc, x, y, z))
+						{
+							// Succeeded, bail out
+							return;
+						}
+					}
+				}  // switch (BlockType)
+			}  // for x
+		}  // for y
+	}  // for y
+}
+
+
+
+
+
+bool cFinishGenFluidSprings::TryPlaceSpring(cChunkDesc & a_ChunkDesc, int x, int y, int z)
+{
+	// In order to place a spring, it needs exactly one of the XZ neighbors or a below neighbor to be air
+	// Also, its neighbor on top of it must be non-air
+	if (a_ChunkDesc.GetBlockType(x, y + 1, z) == E_BLOCK_AIR)
+	{
+		return false;
+	}
+	
+	static const struct
+	{
+		int x, y, z;
+	} Coords[] =
+	{
+		{-1,  0,  0},
+		{ 1,  0,  0},
+		{ 0, -1,  0},
+		{ 0,  0, -1},
+		{ 0,  0,  1},
+	} ;
+	int NumAirNeighbors = 0;
+	for (int i = 0; i < ARRAYCOUNT(Coords); i++)
+	{
+		switch (a_ChunkDesc.GetBlockType(x + Coords[i].x, y + Coords[i].y, z + Coords[i].z))
+		{
+			case E_BLOCK_AIR:
+			{
+				NumAirNeighbors += 1;
+				if (NumAirNeighbors > 1)
+				{
+					return false;
+				}
+			}
+		}
+	}
+	if (NumAirNeighbors == 0)
+	{
+		return false;
+	}
+	
+	// Has exactly one air neighbor, place a spring:
+	a_ChunkDesc.SetBlockTypeMeta(x, y, z, m_Fluid, 0);
+	return true;
+}
+
+
+
+

src/Generating/FinishGen.h

@@ -0,0 +1,185 @@
+
+// FinishGen.h
+
+/* Interfaces to the various finishing generators:
+	- cFinishGenSnow
+	- cFinishGenIce
+	- cFinishGenSprinkleFoliage
+	- cFinishGenLilypads
+	- cFinishGenBottomLava
+	- cFinishGenPreSimulator
+	- cFinishGenDeadBushes
+*/
+
+
+
+
+
+#include "ComposableGenerator.h"
+#include "../Noise.h"
+#include "../ProbabDistrib.h"
+
+
+
+
+
+class cFinishGenSnow :
+	public cFinishGen
+{
+protected:
+	// cFinishGen override:
+	virtual void GenFinish(cChunkDesc & a_ChunkDesc) override;
+} ;
+
+
+
+
+
+class cFinishGenIce :
+	public cFinishGen
+{
+protected:
+	// cFinishGen override:
+	virtual void GenFinish(cChunkDesc & a_ChunkDesc) override;
+} ;
+
+
+
+
+
+class cFinishGenSprinkleFoliage :
+	public cFinishGen
+{
+public:
+	cFinishGenSprinkleFoliage(int a_Seed) : m_Noise(a_Seed), m_Seed(a_Seed) {}
+	
+protected:
+	cNoise m_Noise;
+	int    m_Seed;
+	
+	/// Tries to place sugarcane at the coords specified, returns true if successful
+	bool TryAddSugarcane(cChunkDesc & a_ChunkDesc, int a_RelX, int a_RelY, int a_RelZ);
+	
+	// cFinishGen override:
+	virtual void GenFinish(cChunkDesc & a_ChunkDesc) override;
+} ;
+
+
+
+
+
+/** This class adds a single top block in random positions in the specified biome on top of specified allowed blocks.
+Used for:
+- Lilypads finisher
+- DeadBushes finisher
+*/
+class cFinishGenSingleBiomeSingleTopBlock :
+	public cFinishGen
+{
+public:
+	cFinishGenSingleBiomeSingleTopBlock(
+		int a_Seed, BLOCKTYPE a_BlockType, EMCSBiome a_Biome, int a_Amount,
+		BLOCKTYPE a_AllowedBelow1, BLOCKTYPE a_AllowedBelow2
+	) :
+		m_Noise(a_Seed),
+		m_BlockType(a_BlockType),
+		m_Biome(a_Biome),
+		m_Amount(a_Amount),
+		m_AllowedBelow1(a_AllowedBelow1),
+		m_AllowedBelow2(a_AllowedBelow2)
+	{
+	}
+	
+protected:
+	cNoise m_Noise;
+	BLOCKTYPE m_BlockType;
+	EMCSBiome m_Biome;
+	int       m_Amount;         ///< Relative amount of blocks to try adding. 1 = one block per 256 biome columns.
+	BLOCKTYPE m_AllowedBelow1;  ///< First  of the two blocktypes that are allowed below m_BlockType
+	BLOCKTYPE m_AllowedBelow2;  ///< Second of the two blocktypes that are allowed below m_BlockType
+	
+	int GetNumToGen(const cChunkDef::BiomeMap & a_BiomeMap);
+	
+	// cFinishGen override:
+	virtual void GenFinish(cChunkDesc & a_ChunkDesc) override;
+} ;
+
+
+
+
+
+class cFinishGenBottomLava :
+	public cFinishGen
+{
+public:
+	cFinishGenBottomLava(int a_Level) :
+		m_Level(a_Level)
+	{
+	}
+	
+protected:
+	int m_Level;
+	
+	// cFinishGen override:
+	virtual void GenFinish(cChunkDesc & a_ChunkDesc) override;
+} ;
+
+
+
+
+
+class cFinishGenPreSimulator :
+	public cFinishGen
+{
+public:
+	cFinishGenPreSimulator(void);
+	
+protected:
+	// Drops hanging sand and gravel down to the ground, recalculates heightmap
+	void CollapseSandGravel(
+		cChunkDef::BlockTypes & a_BlockTypes,    // Block types to read and change
+		cChunkDef::HeightMap & a_HeightMap       // Height map to update by the current data
+	);
+	
+	/** For each fluid block:
+	- if all surroundings are of the same fluid, makes it stationary; otherwise makes it flowing (excl. top)
+	- all fluid on the chunk's edge is made flowing
+	*/
+	void StationarizeFluid(
+		cChunkDef::BlockTypes & a_BlockTypes,    // Block types to read and change
+		cChunkDef::HeightMap & a_HeightMap,      // Height map to read
+		BLOCKTYPE a_Fluid,
+		BLOCKTYPE a_StationaryFluid
+	);
+
+	// cFinishGen override:
+	virtual void GenFinish(cChunkDesc & a_ChunkDesc) override;
+} ;
+
+
+
+
+
+class cFinishGenFluidSprings :
+	public cFinishGen
+{
+public:
+	cFinishGenFluidSprings(int a_Seed, BLOCKTYPE a_Fluid, cIniFile & a_IniFile, const cWorld & a_World);
+	
+protected:
+
+	cNoise         m_Noise;
+	cProbabDistrib m_HeightDistribution;
+	BLOCKTYPE      m_Fluid;
+	int            m_Chance;  ///< Chance, [0..100], that a spring will be generated in a chunk
+
+	// cFinishGen override:
+	virtual void GenFinish(cChunkDesc & a_ChunkDesc) override;
+
+	/// Tries to place a spring at the specified coords, checks neighbors. Returns true	if successful
+	bool TryPlaceSpring(cChunkDesc & a_ChunkDesc, int x, int y, int z);
+} ;
+
+
+
+

src/Generating/HeiGen.cpp

@@ -0,0 +1,390 @@
+
+// HeiGen.cpp
+
+// Implements the various terrain height generators
+
+#include "Globals.h"
+#include "HeiGen.h"
+#include "../LinearUpscale.h"
+#include "../../iniFile/iniFile.h"
+
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cHeiGenFlat:
+
+void cHeiGenFlat::GenHeightMap(int a_ChunkX, int a_ChunkZ, cChunkDef::HeightMap & a_HeightMap)
+{
+	for (int i = 0; i < ARRAYCOUNT(a_HeightMap); i++)
+	{
+		a_HeightMap[i] = m_Height;
+	}
+}
+
+
+
+
+
+void cHeiGenFlat::InitializeHeightGen(cIniFile & a_IniFile)
+{
+	m_Height = a_IniFile.GetValueSetI("Generator", "FlatHeight", m_Height);
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cHeiGenCache:
+
+cHeiGenCache::cHeiGenCache(cTerrainHeightGen & a_HeiGenToCache, int a_CacheSize) :
+	m_HeiGenToCache(a_HeiGenToCache),
+	m_CacheSize(a_CacheSize),
+	m_CacheOrder(new int[a_CacheSize]),
+	m_CacheData(new sCacheData[a_CacheSize]),
+	m_NumHits(0),
+	m_NumMisses(0),
+	m_TotalChain(0)
+{
+	for (int i = 0; i < m_CacheSize; i++)
+	{
+		m_CacheOrder[i] = i;
+		m_CacheData[i].m_ChunkX = 0x7fffffff;
+		m_CacheData[i].m_ChunkZ = 0x7fffffff;
+	}
+}
+
+
+
+
+
+cHeiGenCache::~cHeiGenCache()
+{
+	delete[] m_CacheData;
+	delete[] m_CacheOrder;
+}
+
+
+
+
+
+void cHeiGenCache::GenHeightMap(int a_ChunkX, int a_ChunkZ, cChunkDef::HeightMap & a_HeightMap)
+{
+	/*
+	if (((m_NumHits + m_NumMisses) % 1024) == 10)
+	{
+		LOGD("HeiGenCache: %d hits, %d misses, saved %.2f %%", m_NumHits, m_NumMisses, 100.0 * m_NumHits / (m_NumHits + m_NumMisses));
+		LOGD("HeiGenCache: Avg cache chain length: %.2f", (float)m_TotalChain / m_NumHits);
+	}
+	//*/
+	
+	for (int i = 0; i < m_CacheSize; i++)
+	{
+		if (
+			(m_CacheData[m_CacheOrder[i]].m_ChunkX != a_ChunkX) ||
+			(m_CacheData[m_CacheOrder[i]].m_ChunkZ != a_ChunkZ)
+		)
+		{
+			continue;
+		}
+		// Found it in the cache
+		int Idx = m_CacheOrder[i];
+		
+		// Move to front:
+		for (int j = i; j > 0; j--)
+		{
+			m_CacheOrder[j] = m_CacheOrder[j - 1];
+		}
+		m_CacheOrder[0] = Idx;
+		
+		// Use the cached data:
+		memcpy(a_HeightMap, m_CacheData[Idx].m_HeightMap, sizeof(a_HeightMap));
+		
+		m_NumHits++;
+		m_TotalChain += i;
+		return;
+	}  // for i - cache
+	
+	// Not in the cache:
+	m_NumMisses++;
+	m_HeiGenToCache.GenHeightMap(a_ChunkX, a_ChunkZ, a_HeightMap);
+	
+	// Insert it as the first item in the MRU order:
+	int Idx = m_CacheOrder[m_CacheSize - 1];
+	for (int i = m_CacheSize - 1; i > 0; i--)
+	{
+		m_CacheOrder[i] = m_CacheOrder[i - 1];
+	}  // for i - m_CacheOrder[]
+	m_CacheOrder[0] = Idx;
+	memcpy(m_CacheData[Idx].m_HeightMap, a_HeightMap, sizeof(a_HeightMap));
+	m_CacheData[Idx].m_ChunkX = a_ChunkX;
+	m_CacheData[Idx].m_ChunkZ = a_ChunkZ;
+}
+
+
+
+
+
+void cHeiGenCache::InitializeHeightGen(cIniFile & a_IniFile)
+{
+	m_HeiGenToCache.InitializeHeightGen(a_IniFile);
+}
+
+
+
+
+
+bool cHeiGenCache::GetHeightAt(int a_ChunkX, int a_ChunkZ, int a_RelX, int a_RelZ, HEIGHTTYPE & a_Height)
+{
+	for (int i = 0; i < m_CacheSize; i++)
+	{
+		if ((m_CacheData[i].m_ChunkX == a_ChunkX) && (m_CacheData[i].m_ChunkZ == a_ChunkZ))
+		{
+			a_Height = cChunkDef::GetHeight(m_CacheData[i].m_HeightMap, a_RelX, a_RelZ);
+			return true;
+		}
+	}  // for i - m_CacheData[]
+	return false;
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cHeiGenClassic:
+
+cHeiGenClassic::cHeiGenClassic(int a_Seed) :
+	m_Seed(a_Seed),
+	m_Noise(a_Seed)
+{
+}
+
+
+
+
+
+float cHeiGenClassic::GetNoise(float x, float y)
+{
+	float oct1 = m_Noise.CubicNoise2D(x * m_HeightFreq1, y * m_HeightFreq1) * m_HeightAmp1;
+	float oct2 = m_Noise.CubicNoise2D(x * m_HeightFreq2, y * m_HeightFreq2) * m_HeightAmp2;
+	float oct3 = m_Noise.CubicNoise2D(x * m_HeightFreq3, y * m_HeightFreq3) * m_HeightAmp3;
+
+	float height = m_Noise.CubicNoise2D(x * 0.1f, y * 0.1f ) * 2;
+
+	float flatness = ((m_Noise.CubicNoise2D(x * 0.5f, y * 0.5f) + 1.f) * 0.5f) * 1.1f; // 0 ... 1.5
+	flatness *= flatness * flatness;
+
+	return (oct1 + oct2 + oct3) * flatness + height;
+}
+
+
+
+
+
+void cHeiGenClassic::GenHeightMap(int a_ChunkX, int a_ChunkZ, cChunkDef::HeightMap & a_HeightMap)
+{
+	for (int z = 0; z < cChunkDef::Width; z++) 
+	{
+		const float zz = (float)(a_ChunkZ * cChunkDef::Width + z);
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			const float xx = (float)(a_ChunkX * cChunkDef::Width + x);
+			
+			int hei = 64 + (int)(GetNoise(xx * 0.05f, zz * 0.05f) * 16);
+			if (hei < 10)
+			{
+				hei = 10;
+			}
+			if (hei > 250)
+			{
+				hei = 250;
+			}
+			cChunkDef::SetHeight(a_HeightMap, x , z, hei);
+		}  // for x
+	}  // for z
+}
+
+
+
+
+
+void cHeiGenClassic::InitializeHeightGen(cIniFile & a_IniFile)
+{
+	m_HeightFreq1 = (float)a_IniFile.GetValueSetF("Generator", "ClassicHeightFreq1", 0.1);
+	m_HeightFreq2 = (float)a_IniFile.GetValueSetF("Generator", "ClassicHeightFreq2", 1.0);
+	m_HeightFreq3 = (float)a_IniFile.GetValueSetF("Generator", "ClassicHeightFreq3", 2.0);
+	m_HeightAmp1  = (float)a_IniFile.GetValueSetF("Generator", "ClassicHeightAmp1",  1.0);
+	m_HeightAmp2  = (float)a_IniFile.GetValueSetF("Generator", "ClassicHeightAmp2",  0.5);
+	m_HeightAmp3  = (float)a_IniFile.GetValueSetF("Generator", "ClassicHeightAmp3",  0.5);
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cHeiGenBiomal:
+
+const cHeiGenBiomal::sGenParam cHeiGenBiomal::m_GenParam[biNumBiomes] =
+{
+	/*                        Fast-changing | Middle-changing | Slow-changing |*/
+	/* Biome               |  Freq1  | Amp1 | Freq2   | Amp2  | Freq3  | Amp3 | BaseHeight */
+	/* biOcean            */ { 0.1f,   2.0f,  0.05f,    12.0f,  0.01f,   10.0f,  40},
+	/* biPlains           */ { 0.1f,   1.0f,  0.05f,     1.5f,  0.01f,    4.0f,  68},
+	/* biDesert           */ { 0.1f,   1.0f,  0.05f,     1.5f,  0.01f,    4.0f,  68},
+	/* biExtremeHills     */ { 0.2f,   4.0f,  0.05f,    20.0f,  0.01f,   16.0f, 100},
+	/* biForest           */ { 0.1f,   1.0f,  0.05f,     2.0f,  0.01f,    4.0f,  70},
+	/* biTaiga            */ { 0.1f,   1.0f,  0.05f,     2.0f,  0.01f,    4.0f,  70},
+	/* biSwampland        */ { 0.1f,   1.1f,  0.05f,     1.5f,  0.02f,    2.5f,  61.5},
+	/* biRiver            */ { 0.2f,   0.1f,  0.05f,     0.1f,  0.01f,    0.1f,  56},
+	/* biNether           */ { 0.1f,   0.0f,  0.01f,     0.0f,  0.01f,    0.0f,   0},  // Unused, but must be here due to indexing
+	/* biSky              */ { 0.1f,   0.0f,  0.01f,     0.0f,  0.01f,    0.0f,   0},  // Unused, but must be here due to indexing
+	/* biFrozenOcean      */ { 0.1f,   2.0f,  0.05f,    12.0f,  0.01f,   10.0f,  40},
+	/* biFrozenRiver      */ { 0.2f,   0.1f,  0.05f,     0.1f,  0.01f,    0.1f,  56},
+	/* biIcePlains        */ { 0.1f,   1.0f,  0.05f,     1.5f,  0.01f,    4.0f,  68},
+	/* biIceMountains     */ { 0.2f,   2.0f,  0.05f,    10.0f,  0.01f,    8.0f,  80},
+	/* biMushroomIsland   */ { 0.1f,   2.0f,  0.05f,     8.0f,  0.01f,    6.0f,  80},
+	/* biMushroomShore    */ { 0.1f,   1.0f,  0.05f,     2.0f,  0.01f,    4.0f,  64},
+	/* biBeach            */ { 0.1f,   0.5f,  0.05f,     1.0f,  0.01f,    1.0f,  64},
+	/* biDesertHills      */ { 0.2f,   2.0f,  0.05f,     5.0f,  0.01f,    4.0f,  75},
+	/* biForestHills      */ { 0.2f,   2.0f,  0.05f,    12.0f,  0.01f,   10.0f,  80},
+	/* biTaigaHills       */ { 0.2f,   2.0f,  0.05f,    12.0f,  0.01f,   10.0f,  80},
+	/* biExtremeHillsEdge */ { 0.2f,   3.0f,  0.05f,    16.0f,  0.01f,   12.0f,  80},
+	/* biJungle           */ { 0.1f,   3.0f,  0.05f,     6.0f,  0.01f,    6.0f,  70},
+	/* biJungleHills      */ { 0.2f,   3.0f,  0.05f,    12.0f,  0.01f,   10.0f,  80},
+} ;
+
+
+
+
+
+void cHeiGenBiomal::GenHeightMap(int a_ChunkX, int a_ChunkZ, cChunkDef::HeightMap & a_HeightMap)
+{
+	// Generate a 3x3 chunk area of biomes around this chunk:
+	BiomeNeighbors Biomes;
+	for (int z = -1; z <= 1; z++)
+	{
+		for (int x = -1; x <= 1; x++)
+		{
+			m_BiomeGen.GenBiomes(a_ChunkX + x, a_ChunkZ + z, Biomes[x + 1][z + 1]);
+		}  // for x
+	}  // for z
+	
+	/*
+	_X 2013_04_22:
+	There's no point in precalculating the entire perlin noise arrays, too many values are calculated uselessly,
+	resulting in speed DEcrease.
+	*/
+	
+	//*
+	// Linearly interpolate 4x4 blocks of heightmap:
+	// Must be done on a floating point datatype, else the results are ugly!
+	const int STEPZ = 4;  // Must be a divisor of 16
+	const int STEPX = 4;  // Must be a divisor of 16
+	NOISE_DATATYPE Height[17 * 17];
+	for (int z = 0; z < 17; z += STEPZ)
+	{
+		for (int x = 0; x < 17; x += STEPX)
+		{
+			Height[x + 17 * z] = GetHeightAt(x, z, a_ChunkX, a_ChunkZ, Biomes);
+		}
+	}
+	LinearUpscale2DArrayInPlace(Height, 17, 17, STEPX, STEPZ);
+	
+	// Copy into the heightmap
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			cChunkDef::SetHeight(a_HeightMap, x, z, (int)Height[x + 17 * z]);
+		}
+	}
+	//*/
+	
+	/*
+	// For each height, go through neighboring biomes and add up their idea of height:
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			cChunkDef::SetHeight(a_HeightMap, x, z, GetHeightAt(x, z, a_ChunkX, a_ChunkZ, Biomes));
+		}  // for x
+	}
+	//*/
+}
+
+
+
+
+
+void cHeiGenBiomal::InitializeHeightGen(cIniFile & a_IniFile)
+{
+	// No user-settable params
+}
+
+
+
+
+
+NOISE_DATATYPE cHeiGenBiomal::GetHeightAt(int a_RelX, int a_RelZ, int a_ChunkX, int a_ChunkZ, const cHeiGenBiomal::BiomeNeighbors & a_BiomeNeighbors)
+{
+	// Sum up how many biomes of each type there are in the neighborhood:
+	int BiomeCounts[biNumBiomes];
+	memset(BiomeCounts, 0, sizeof(BiomeCounts));
+	int Sum = 0;
+	for (int z = -8; z <= 8; z++)
+	{
+		int FinalZ = a_RelZ + z + cChunkDef::Width;
+		int IdxZ = FinalZ / cChunkDef::Width;
+		int ModZ = FinalZ % cChunkDef::Width;
+		int WeightZ = 9 - abs(z);
+		for (int x = -8; x <= 8; x++)
+		{
+			int FinalX = a_RelX + x + cChunkDef::Width;
+			int IdxX = FinalX / cChunkDef::Width;
+			int ModX = FinalX % cChunkDef::Width;
+			EMCSBiome Biome = cChunkDef::GetBiome(a_BiomeNeighbors[IdxX][IdxZ], ModX, ModZ);
+			if ((Biome < 0) || (Biome >= ARRAYCOUNT(BiomeCounts)))
+			{
+				continue;
+			}
+			int WeightX = 9 - abs(x);
+			BiomeCounts[Biome] += WeightX + WeightZ;
+			Sum += WeightX + WeightZ;
+		}  // for x
+	}  // for z
+	
+	// For each biome type that has a nonzero count, calc its height and add it:
+	if (Sum > 0)
+	{
+		NOISE_DATATYPE Height = 0;
+		int BlockX = a_ChunkX * cChunkDef::Width + a_RelX;
+		int BlockZ = a_ChunkZ * cChunkDef::Width + a_RelZ;
+		for (int i = 0; i < ARRAYCOUNT(BiomeCounts); i++)
+		{
+			if (BiomeCounts[i] == 0)
+			{
+				continue;
+			}
+			NOISE_DATATYPE oct1 = m_Noise.CubicNoise2D(BlockX * m_GenParam[i].m_HeightFreq1, BlockZ * m_GenParam[i].m_HeightFreq1) * m_GenParam[i].m_HeightAmp1;
+			NOISE_DATATYPE oct2 = m_Noise.CubicNoise2D(BlockX * m_GenParam[i].m_HeightFreq2, BlockZ * m_GenParam[i].m_HeightFreq2) * m_GenParam[i].m_HeightAmp2;
+			NOISE_DATATYPE oct3 = m_Noise.CubicNoise2D(BlockX * m_GenParam[i].m_HeightFreq3, BlockZ * m_GenParam[i].m_HeightFreq3) * m_GenParam[i].m_HeightAmp3;
+			Height += BiomeCounts[i] * (m_GenParam[i].m_BaseHeight + oct1 + oct2 + oct3);
+		}
+		NOISE_DATATYPE res = Height / Sum;
+		return std::min((NOISE_DATATYPE)250, std::max(res, (NOISE_DATATYPE)5));
+	}
+	
+	// No known biome around? Weird. Return a bogus value:
+	ASSERT(!"cHeiGenBiomal: Biome sum failed, no known biome around");
+	return 5;
+}
+
+
+
+
+

src/Generating/HeiGen.h

@@ -0,0 +1,145 @@
+
+// HeiGen.h
+
+/*
+Interfaces to the various height generators:
+	- cHeiGenFlat
+	- cHeiGenClassic
+	- cHeiGenBiomal
+*/
+
+
+
+
+
+#pragma once
+
+#include "ComposableGenerator.h"
+#include "../Noise.h"
+
+
+
+
+
+class cHeiGenFlat :
+	public cTerrainHeightGen
+{
+public:
+	cHeiGenFlat(void) : m_Height(5) {}
+	
+protected:
+
+	int m_Height;
+
+	// cTerrainHeightGen overrides:
+	virtual void GenHeightMap(int a_ChunkX, int a_ChunkZ, cChunkDef::HeightMap & a_HeightMap) override;
+	virtual void InitializeHeightGen(cIniFile & a_IniFile) override;
+} ;
+
+
+
+
+
+/// A simple cache that stores N most recently generated chunks' heightmaps; N being settable upon creation
+class cHeiGenCache :
+	public cTerrainHeightGen
+{
+public:
+	cHeiGenCache(cTerrainHeightGen & a_HeiGenToCache, int a_CacheSize);  // Doesn't take ownership of a_HeiGenToCache
+	~cHeiGenCache();
+	
+	// cTerrainHeightGen overrides:
+	virtual void GenHeightMap(int a_ChunkX, int a_ChunkZ, cChunkDef::HeightMap & a_HeightMap) override;
+	virtual void InitializeHeightGen(cIniFile & a_IniFile) override;
+	
+	/// Retrieves height at the specified point in the cache, returns true if found, false if not found
+	bool GetHeightAt(int a_ChunkX, int a_ChunkZ, int a_RelX, int a_RelZ, HEIGHTTYPE & a_Height);
+	
+protected:
+
+	cTerrainHeightGen & m_HeiGenToCache;
+	
+	struct sCacheData
+	{
+		int m_ChunkX;
+		int m_ChunkZ;
+		cChunkDef::HeightMap m_HeightMap;
+	} ;
+	
+	// To avoid moving large amounts of data for the MRU behavior, we MRU-ize indices to an array of the actual data
+	int          m_CacheSize;
+	int *        m_CacheOrder;  // MRU-ized order, indices into m_CacheData array
+	sCacheData * m_CacheData;   // m_CacheData[m_CacheOrder[0]] is the most recently used
+	
+	// Cache statistics
+	int m_NumHits;
+	int m_NumMisses;
+	int m_TotalChain;  // Number of cache items walked to get to a hit (only added for hits)
+} ;
+
+
+
+
+
+class cHeiGenClassic :
+	public cTerrainHeightGen
+{
+public:
+	cHeiGenClassic(int a_Seed);
+	
+protected:
+
+	int m_Seed;
+	cNoise m_Noise;
+	float m_HeightFreq1, m_HeightAmp1;
+	float m_HeightFreq2, m_HeightAmp2;
+	float m_HeightFreq3, m_HeightAmp3;
+	
+	float GetNoise(float x, float y);
+
+	// cTerrainHeightGen overrides:
+	virtual void GenHeightMap(int a_ChunkX, int a_ChunkZ, cChunkDef::HeightMap & a_HeightMap) override;
+	virtual void InitializeHeightGen(cIniFile & a_IniFile) override;
+} ;
+
+
+
+
+
+class cHeiGenBiomal :
+	public cTerrainHeightGen
+{
+public:
+	cHeiGenBiomal(int a_Seed, cBiomeGen & a_BiomeGen) :
+		m_Noise(a_Seed),
+		m_BiomeGen(a_BiomeGen)
+	{
+	}
+	
+protected:
+
+	typedef cChunkDef::BiomeMap BiomeNeighbors[3][3];
+
+	cNoise      m_Noise;
+	cBiomeGen & m_BiomeGen;
+	
+	// Per-biome terrain generator parameters:
+	struct sGenParam
+	{
+		float m_HeightFreq1, m_HeightAmp1;
+		float m_HeightFreq2, m_HeightAmp2;
+		float m_HeightFreq3, m_HeightAmp3;
+		float m_BaseHeight;
+	} ;
+	static const sGenParam m_GenParam[biNumBiomes];
+	
+	// cTerrainHeightGen overrides:
+	virtual void GenHeightMap(int a_ChunkX, int a_ChunkZ, cChunkDef::HeightMap & a_HeightMap) override;
+	virtual void InitializeHeightGen(cIniFile & a_IniFile) override;
+	
+	NOISE_DATATYPE GetHeightAt(int a_RelX, int a_RelZ, int a_ChunkX, int a_ChunkZ, const BiomeNeighbors & a_BiomeNeighbors);
+} ;
+
+
+
+

src/Generating/MineShafts.h

@@ -0,0 +1,61 @@
+
+// MineShafts.h
+
+// Declares the cStructGenMineShafts class representing the structure generator for abandoned mineshafts
+
+
+
+
+
+#pragma once
+
+#include "ComposableGenerator.h"
+#include "../Noise.h"
+
+
+
+
+
+class cStructGenMineShafts :
+	public cStructureGen
+{
+public:
+	cStructGenMineShafts(
+		int a_Seed, int a_GridSize, int a_MaxSystemSize,
+		int a_ChanceCorridor, int a_ChanceCrossing, int a_ChanceStaircase
+	);
+	
+	virtual ~cStructGenMineShafts();
+	
+protected:
+	friend class cMineShaft;
+	friend class cMineShaftDirtRoom;
+	friend class cMineShaftCorridor;
+	friend class cMineShaftCrossing;
+	friend class cMineShaftStaircase;
+	class cMineShaftSystem;  // fwd: MineShafts.cpp
+	typedef std::list<cMineShaftSystem *> cMineShaftSystems;
+	
+	cNoise            m_Noise;
+	int               m_GridSize;            ///< Average spacing of the systems
+	int               m_MaxSystemSize;       ///< Maximum blcok size of a mineshaft system
+	int               m_ProbLevelCorridor;   ///< Probability level of a branch object being the corridor
+	int               m_ProbLevelCrossing;   ///< Probability level of a branch object being the crossing, minus Corridor
+	int               m_ProbLevelStaircase;  ///< Probability level of a branch object being the staircase, minus Crossing
+	cMineShaftSystems m_Cache;               ///< Cache of the most recently used systems. MoveToFront used.
+	
+	/// Clears everything from the cache
+	void ClearCache(void);
+	
+	/** Returns all systems that *may* intersect the given chunk.
+	All the systems are valid until the next call to this function (which may delete some of the pointers).
+	*/
+	void GetMineShaftSystemsForChunk(int a_ChunkX, int a_ChunkZ, cMineShaftSystems & a_MineShaftSystems);
+
+	// cStructureGen overrides:
+	virtual void GenStructures(cChunkDesc & a_ChunkDesc) override;
+} ;
+
+
+
+

src/Generating/Noise3DGenerator.cpp

@@ -0,0 +1,581 @@
+
+// Nosie3DGenerator.cpp
+
+// Generates terrain using 3D noise, rather than composing. Is a test.
+
+#include "Globals.h"
+#include "Noise3DGenerator.h"
+#include "../OSSupport/File.h"
+#include "../../iniFile/iniFile.h"
+#include "../LinearInterpolation.h"
+#include "../LinearUpscale.h"
+
+
+
+
+
+/*
+// Perform an automatic test of upscaling upon program start (use breakpoints to debug):
+
+class Test
+{
+public:
+	Test(void)
+	{
+		DoTest1();
+		DoTest2();
+	}
+	
+	
+	void DoTest1(void)
+	{
+		float In[3 * 3 * 3];
+		for (int i = 0; i < ARRAYCOUNT(In); i++)
+		{
+			In[i] = (float)(i % 5);
+		}
+		Debug3DNoise(In, 3, 3, 3, "Upscale3D in");
+		float Out[17 * 33 * 35];
+		LinearUpscale3DArray(In, 3, 3, 3, Out, 8, 16, 17);
+		Debug3DNoise(Out, 17, 33, 35, "Upscale3D test");
+	}
+	
+	
+	void DoTest2(void)
+	{
+		float In[3 * 3];
+		for (int i = 0; i < ARRAYCOUNT(In); i++)
+		{
+			In[i] = (float)(i % 5);
+		}
+		Debug2DNoise(In, 3, 3, "Upscale2D in");
+		float Out[17 * 33];
+		LinearUpscale2DArray(In, 3, 3, Out, 8, 16);
+		Debug2DNoise(Out, 17, 33, "Upscale2D test");
+	}
+	
+} gTest;
+//*/
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cNoise3DGenerator:
+
+cNoise3DGenerator::cNoise3DGenerator(cChunkGenerator & a_ChunkGenerator) :
+	super(a_ChunkGenerator),
+	m_Perlin(1000),
+	m_Cubic(1000)
+{
+	m_Perlin.AddOctave(1, (NOISE_DATATYPE)0.5);
+	m_Perlin.AddOctave((NOISE_DATATYPE)0.5, 1);
+	m_Perlin.AddOctave((NOISE_DATATYPE)0.5, 2);
+	
+	#if 0
+	// DEBUG: Test the noise generation:
+	// NOTE: In order to be able to run MCS with this code, you need to increase the default thread stack size
+	// In MSVC, it is done in Project Settings -> Configuration Properties -> Linker -> System, set Stack reserve size to at least 64M
+	m_SeaLevel            = 62;
+	m_HeightAmplification = 0;
+	m_MidPoint            = 75;
+	m_FrequencyX          = 4;
+	m_FrequencyY          = 4;
+	m_FrequencyZ          = 4;
+	m_AirThreshold        = 0.5;
+	
+	const int NumChunks = 4;
+	NOISE_DATATYPE Noise[NumChunks][cChunkDef::Width * cChunkDef::Width * cChunkDef::Height];
+	for (int x = 0; x < NumChunks; x++)
+	{
+		GenerateNoiseArray(x, 5, Noise[x]);
+	}
+
+	// Save in XY cuts:
+	cFile f1;
+	if (f1.Open("Test_XY.grab", cFile::fmWrite))
+	{
+		for (int z = 0; z < cChunkDef::Width; z++)
+		{
+			for (int y = 0; y < cChunkDef::Height; y++)
+			{
+				for (int i = 0; i < NumChunks; i++)
+				{
+					int idx = y * cChunkDef::Width + z * cChunkDef::Width * cChunkDef::Height;
+					unsigned char buf[cChunkDef::Width];
+					for (int x = 0; x < cChunkDef::Width; x++)
+					{
+						buf[x] = (unsigned char)(std::min(256, std::max(0, (int)(128 + 32 * Noise[i][idx++]))));
+					}
+					f1.Write(buf, cChunkDef::Width);
+				}
+			}  // for y
+		}  // for z
+	}  // if (XY file open)
+
+	cFile f2;
+	if (f2.Open("Test_XZ.grab", cFile::fmWrite))
+	{
+		for (int y = 0; y < cChunkDef::Height; y++)
+		{
+			for (int z = 0; z < cChunkDef::Width; z++)
+			{
+				for (int i = 0; i < NumChunks; i++)
+				{
+					int idx = y * cChunkDef::Width + z * cChunkDef::Width * cChunkDef::Height;
+					unsigned char buf[cChunkDef::Width];
+					for (int x = 0; x < cChunkDef::Width; x++)
+					{
+						buf[x] = (unsigned char)(std::min(256, std::max(0, (int)(128 + 32 * Noise[i][idx++]))));
+					}
+					f2.Write(buf, cChunkDef::Width);
+				}
+			}  // for z
+		}  // for y
+	}  // if (XZ file open)
+	#endif  // 0
+}
+
+
+
+
+
+cNoise3DGenerator::~cNoise3DGenerator()
+{
+	// Nothing needed yet
+}
+
+
+
+
+
+void cNoise3DGenerator::Initialize(cWorld * a_World, cIniFile & a_IniFile)
+{
+	m_World = a_World;
+	
+	// Params:
+	m_SeaLevel            =                 a_IniFile.GetValueSetI("Generator", "Noise3DSeaLevel", 62);
+	m_HeightAmplification = (NOISE_DATATYPE)a_IniFile.GetValueSetF("Generator", "Noise3DHeightAmplification", 0);
+	m_MidPoint            = (NOISE_DATATYPE)a_IniFile.GetValueSetF("Generator", "Noise3DMidPoint", 75);
+	m_FrequencyX          = (NOISE_DATATYPE)a_IniFile.GetValueSetF("Generator", "Noise3DFrequencyX", 8);
+	m_FrequencyY          = (NOISE_DATATYPE)a_IniFile.GetValueSetF("Generator", "Noise3DFrequencyY", 8);
+	m_FrequencyZ          = (NOISE_DATATYPE)a_IniFile.GetValueSetF("Generator", "Noise3DFrequencyZ", 8);
+	m_AirThreshold        = (NOISE_DATATYPE)a_IniFile.GetValueSetF("Generator", "Noise3DAirThreshold", 0.5);
+}
+
+
+
+
+
+void cNoise3DGenerator::GenerateBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap)
+{
+	for (int i = 0; i < ARRAYCOUNT(a_BiomeMap); i++)
+	{
+		a_BiomeMap[i] = biExtremeHills;
+	}
+}
+
+
+
+
+
+void cNoise3DGenerator::DoGenerate(int a_ChunkX, int a_ChunkZ, cChunkDesc & a_ChunkDesc)
+{
+	NOISE_DATATYPE Noise[17 * 257 * 17];
+	GenerateNoiseArray(a_ChunkX, a_ChunkZ, Noise);
+	
+	// Output noise into chunk:
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int y = 0; y < cChunkDef::Height; y++)
+		{
+			int idx = z * 17 * 257 + y * 17;
+			for (int x = 0; x < cChunkDef::Width; x++)
+			{
+				NOISE_DATATYPE n = Noise[idx++];
+				BLOCKTYPE BlockType;
+				if (n > m_AirThreshold)
+				{
+					BlockType = (y > m_SeaLevel) ? E_BLOCK_AIR : E_BLOCK_STATIONARY_WATER;
+				}
+				else
+				{
+					BlockType = E_BLOCK_STONE;
+				}
+				a_ChunkDesc.SetBlockType(x, y, z, BlockType);
+			}
+		}
+	}
+	
+	UpdateHeightmap(a_ChunkDesc);
+	ComposeTerrain (a_ChunkDesc);
+}
+
+
+
+
+
+void cNoise3DGenerator::GenerateNoiseArray(int a_ChunkX, int a_ChunkZ, NOISE_DATATYPE * a_OutNoise)
+{
+	NOISE_DATATYPE NoiseO[DIM_X * DIM_Y * DIM_Z];  // Output for the Perlin noise
+	NOISE_DATATYPE NoiseW[DIM_X * DIM_Y * DIM_Z];  // Workspace that the noise calculation can use and trash
+
+	// Our noise array has different layout, XZY, instead of regular chunk's XYZ, that's why the coords are "renamed"
+	NOISE_DATATYPE StartX = ((NOISE_DATATYPE)(a_ChunkX       * cChunkDef::Width))     / m_FrequencyX;
+	NOISE_DATATYPE EndX   = ((NOISE_DATATYPE)((a_ChunkX + 1) * cChunkDef::Width) - 1) / m_FrequencyX;
+	NOISE_DATATYPE StartZ = ((NOISE_DATATYPE)(a_ChunkZ       * cChunkDef::Width))     / m_FrequencyZ;
+	NOISE_DATATYPE EndZ   = ((NOISE_DATATYPE)((a_ChunkZ + 1) * cChunkDef::Width) - 1) / m_FrequencyZ;
+	NOISE_DATATYPE StartY = 0;
+	NOISE_DATATYPE EndY   = ((NOISE_DATATYPE)256) / m_FrequencyY;
+	
+	m_Perlin.Generate3D(NoiseO, DIM_X, DIM_Y, DIM_Z, StartX, EndX, StartY, EndY, StartZ, EndZ, NoiseW);
+	
+	// DEBUG: Debug3DNoise(NoiseO, DIM_X, DIM_Y, DIM_Z, Printf("Chunk_%d_%d_orig", a_ChunkX, a_ChunkZ));
+	
+	// Precalculate a "height" array:
+	NOISE_DATATYPE Height[DIM_X * DIM_Z];  // Output for the cubic noise heightmap ("source")
+	m_Cubic.Generate2D(Height, DIM_X, DIM_Z, StartX / 25, EndX / 25, StartZ / 25, EndZ / 25);
+	for (int i = 0; i < ARRAYCOUNT(Height); i++)
+	{
+		Height[i] = abs(Height[i]) * m_HeightAmplification + 1;
+	}
+	
+	// Modify the noise by height data:
+	for (int y = 0; y < DIM_Y; y++)
+	{
+		NOISE_DATATYPE AddHeight = (y * UPSCALE_Y - m_MidPoint) / 20;
+		AddHeight *= AddHeight * AddHeight;
+		for (int z = 0; z < DIM_Z; z++)
+		{
+			NOISE_DATATYPE * CurRow = &(NoiseO[y * DIM_X + z * DIM_X * DIM_Y]);
+			for (int x = 0; x < DIM_X; x++)
+			{
+				CurRow[x] += AddHeight / Height[x + DIM_X * z];
+			}
+		}
+	}
+
+	// DEBUG: Debug3DNoise(NoiseO, DIM_X, DIM_Y, DIM_Z, Printf("Chunk_%d_%d_hei", a_ChunkX, a_ChunkZ));
+	
+	// Upscale the Perlin noise into full-blown chunk dimensions:
+	LinearUpscale3DArray(
+		NoiseO, DIM_X, DIM_Y, DIM_Z,
+		a_OutNoise, UPSCALE_X, UPSCALE_Y, UPSCALE_Z
+	);
+	
+	// DEBUG: Debug3DNoise(a_OutNoise, 17, 257, 17, Printf("Chunk_%d_%d_lerp", a_ChunkX, a_ChunkZ));
+}
+
+
+
+
+
+void cNoise3DGenerator::UpdateHeightmap(cChunkDesc & a_ChunkDesc)
+{
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			for (int y = cChunkDef::Height - 1; y > 0; y--)
+			{
+				if (a_ChunkDesc.GetBlockType(x, y, z) != E_BLOCK_AIR)
+				{
+					a_ChunkDesc.SetHeight(x, z, y);
+					break;
+				}
+			}  // for y
+		}  // for x
+	}  // for z
+}
+
+
+
+
+
+void cNoise3DGenerator::ComposeTerrain(cChunkDesc & a_ChunkDesc)
+{
+	// Make basic terrain composition:
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			int LastAir = a_ChunkDesc.GetHeight(x, z) + 1;
+			bool HasHadWater = false;
+			for (int y = LastAir - 1; y > 0; y--)
+			{
+				switch (a_ChunkDesc.GetBlockType(x, y, z))
+				{
+					case E_BLOCK_AIR:
+					{
+						LastAir = y;
+						break;
+					}
+					case E_BLOCK_STONE:
+					{
+						if (LastAir - y > 3)
+						{
+							break;
+						}
+						if (HasHadWater)
+						{
+							a_ChunkDesc.SetBlockType(x, y, z, E_BLOCK_SAND);
+						}
+						else
+						{
+							a_ChunkDesc.SetBlockType(x, y, z, (LastAir == y + 1) ? E_BLOCK_GRASS : E_BLOCK_DIRT);
+						}
+						break;
+					}
+					case E_BLOCK_STATIONARY_WATER:
+					{
+						LastAir = y;
+						HasHadWater = true;
+						break;
+					}
+				}  // switch (GetBlockType())
+			}  // for y
+			a_ChunkDesc.SetBlockType(x, 0, z, E_BLOCK_BEDROCK);
+		}  // for x
+	}  // for z
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cNoise3DComposable:
+
+cNoise3DComposable::cNoise3DComposable(int a_Seed) :
+	m_Noise1(a_Seed + 1000),
+	m_Noise2(a_Seed + 2000),
+	m_Noise3(a_Seed + 3000)
+{
+}
+
+
+
+
+
+void cNoise3DComposable::Initialize(cIniFile & a_IniFile)
+{
+	// Params:
+	m_SeaLevel            =                 a_IniFile.GetValueSetI("Generator", "Noise3DSeaLevel", 62);
+	m_HeightAmplification = (NOISE_DATATYPE)a_IniFile.GetValueSetF("Generator", "Noise3DHeightAmplification", 0);
+	m_MidPoint            = (NOISE_DATATYPE)a_IniFile.GetValueSetF("Generator", "Noise3DMidPoint", 75);
+	m_FrequencyX          = (NOISE_DATATYPE)a_IniFile.GetValueSetF("Generator", "Noise3DFrequencyX", 10);
+	m_FrequencyY          = (NOISE_DATATYPE)a_IniFile.GetValueSetF("Generator", "Noise3DFrequencyY", 10);
+	m_FrequencyZ          = (NOISE_DATATYPE)a_IniFile.GetValueSetF("Generator", "Noise3DFrequencyZ", 10);
+	m_AirThreshold        = (NOISE_DATATYPE)a_IniFile.GetValueSetF("Generator", "Noise3DAirThreshold", 0.5);
+}
+
+
+
+
+
+void cNoise3DComposable::GenerateNoiseArrayIfNeeded(int a_ChunkX, int a_ChunkZ)
+{
+	if ((a_ChunkX == m_LastChunkX) && (a_ChunkZ == m_LastChunkZ))
+	{
+		// The noise for this chunk is already generated in m_Noise
+		return;
+	}
+	m_LastChunkX = a_ChunkX;
+	m_LastChunkZ = a_ChunkZ;
+	
+	// Upscaling parameters:
+	const int UPSCALE_X = 8;
+	const int UPSCALE_Y = 4;
+	const int UPSCALE_Z = 8;
+	
+	const int DIM_X = 1 + cChunkDef::Width  / UPSCALE_X;
+	const int DIM_Y = 1 + cChunkDef::Height / UPSCALE_Y;
+	const int DIM_Z = 1 + cChunkDef::Width  / UPSCALE_Z;
+
+	// Precalculate a "height" array:
+	NOISE_DATATYPE Height[17 * 17];  // x + 17 * z
+	for (int z = 0; z < 17; z += UPSCALE_Z)
+	{
+		NOISE_DATATYPE NoiseZ = ((NOISE_DATATYPE)(a_ChunkZ * cChunkDef::Width + z)) / m_FrequencyZ;
+		for (int x = 0; x < 17; x += UPSCALE_X)
+		{
+			NOISE_DATATYPE NoiseX = ((NOISE_DATATYPE)(a_ChunkX * cChunkDef::Width + x)) / m_FrequencyX;
+			NOISE_DATATYPE val = abs(m_Noise1.CubicNoise2D(NoiseX / 5, NoiseZ / 5)) * m_HeightAmplification + 1;
+			Height[x + 17 * z] = val * val * val;
+		}
+	}
+		
+	int idx = 0;
+	for (int y = 0; y < 257; y += UPSCALE_Y)
+	{
+		NOISE_DATATYPE NoiseY = ((NOISE_DATATYPE)y) / m_FrequencyY;
+		NOISE_DATATYPE AddHeight = (y - m_MidPoint) / 20;
+		AddHeight *= AddHeight * AddHeight;
+		NOISE_DATATYPE * CurFloor = &(m_NoiseArray[y * 17 * 17]);
+		for (int z = 0; z < 17; z += UPSCALE_Z)
+		{
+			NOISE_DATATYPE NoiseZ = ((NOISE_DATATYPE)(a_ChunkZ * cChunkDef::Width + z)) / m_FrequencyZ;
+			for (int x = 0; x < 17; x += UPSCALE_X)
+			{
+				NOISE_DATATYPE NoiseX = ((NOISE_DATATYPE)(a_ChunkX * cChunkDef::Width + x)) / m_FrequencyX;
+				CurFloor[x + 17 * z] = 
+					m_Noise1.CubicNoise3D(NoiseX, NoiseY, NoiseZ) * (NOISE_DATATYPE)0.5 +
+					m_Noise2.CubicNoise3D(NoiseX / 2, NoiseY / 2, NoiseZ / 2) +
+					m_Noise3.CubicNoise3D(NoiseX / 4, NoiseY / 4, NoiseZ / 4) * 2 +
+					AddHeight / Height[x + 17 * z];
+			}
+		}
+		// Linear-interpolate this XZ floor:
+		LinearUpscale2DArrayInPlace(CurFloor, 17, 17, UPSCALE_X, UPSCALE_Z);
+	}
+	
+	// Finish the 3D linear interpolation by interpolating between each XZ-floors on the Y axis
+	for (int y = 1; y < cChunkDef::Height; y++)
+	{
+		if ((y % UPSCALE_Y) == 0)
+		{
+			// This is the interpolation source floor, already calculated
+			continue;
+		}
+		int LoFloorY = (y / UPSCALE_Y) * UPSCALE_Y;
+		int HiFloorY = LoFloorY + UPSCALE_Y;
+		NOISE_DATATYPE * LoFloor  = &(m_NoiseArray[LoFloorY * 17 * 17]);
+		NOISE_DATATYPE * HiFloor  = &(m_NoiseArray[HiFloorY * 17 * 17]);
+		NOISE_DATATYPE * CurFloor = &(m_NoiseArray[y * 17 * 17]);
+		NOISE_DATATYPE Ratio = ((NOISE_DATATYPE)(y % UPSCALE_Y)) / UPSCALE_Y;
+		int idx = 0;
+		for (int z = 0; z < cChunkDef::Width; z++)
+		{
+			for (int x = 0; x < cChunkDef::Width; x++)
+			{
+				CurFloor[idx] = LoFloor[idx] + (HiFloor[idx] - LoFloor[idx]) * Ratio;
+				idx += 1;
+			}
+			idx += 1;  // Skipping one X column
+		}
+	}
+	
+	// The noise array is now fully interpolated
+	/*
+	// DEBUG: Output two images of the array, sliced by XY and XZ:
+	cFile f1;
+	if (f1.Open(Printf("Chunk_%d_%d_XY.raw", a_ChunkX, a_ChunkZ), cFile::fmWrite))
+	{
+		for (int z = 0; z < cChunkDef::Width; z++)
+		{
+			for (int y = 0; y < cChunkDef::Height; y++)
+			{
+				int idx = y * 17 * 17 + z * 17;
+				unsigned char buf[16];
+				for (int x = 0; x < cChunkDef::Width; x++)
+				{
+					buf[x] = (unsigned char)(std::min(256, std::max(0, (int)(128 + 128 * m_Noise[idx++]))));
+				}
+				f1.Write(buf, 16);
+			}  // for y
+		}  // for z
+	}  // if (XY file open)
+
+	cFile f2;
+	if (f2.Open(Printf("Chunk_%d_%d_XZ.raw", a_ChunkX, a_ChunkZ), cFile::fmWrite))
+	{
+		for (int y = 0; y < cChunkDef::Height; y++)
+		{
+			for (int z = 0; z < cChunkDef::Width; z++)
+			{
+				int idx = y * 17 * 17 + z * 17;
+				unsigned char buf[16];
+				for (int x = 0; x < cChunkDef::Width; x++)
+				{
+					buf[x] = (unsigned char)(std::min(256, std::max(0, (int)(128 + 128 * m_Noise[idx++]))));
+				}
+				f2.Write(buf, 16);
+			}  // for z
+		}  // for y
+	}  // if (XZ file open)
+	*/
+}
+
+
+
+
+
+void cNoise3DComposable::GenHeightMap(int a_ChunkX, int a_ChunkZ, cChunkDef::HeightMap & a_HeightMap)
+{
+	GenerateNoiseArrayIfNeeded(a_ChunkX, a_ChunkZ);
+	
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			cChunkDef::SetHeight(a_HeightMap, x, z, m_SeaLevel);
+			for (int y = cChunkDef::Height - 1; y > m_SeaLevel; y--)
+			{
+				if (m_NoiseArray[y * 17 * 17 + z * 17 + x] <= m_AirThreshold)
+				{
+					cChunkDef::SetHeight(a_HeightMap, x, z, y);
+					break;
+				}
+			}  // for y
+		}  // for x
+	}  // for z
+}
+
+
+
+
+
+void cNoise3DComposable::ComposeTerrain(cChunkDesc & a_ChunkDesc)
+{
+	GenerateNoiseArrayIfNeeded(a_ChunkDesc.GetChunkX(), a_ChunkDesc.GetChunkZ());
+	
+	a_ChunkDesc.FillBlocks(E_BLOCK_AIR, 0);
+	
+	// Make basic terrain composition:
+	for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		for (int x = 0; x < cChunkDef::Width; x++)
+		{
+			int LastAir = a_ChunkDesc.GetHeight(x, z) + 1;
+			bool HasHadWater = false;
+			for (int y = LastAir; y < m_SeaLevel; y++)
+			{
+				a_ChunkDesc.SetBlockType(x, y, z, E_BLOCK_STATIONARY_WATER);
+			}
+			for (int y = LastAir - 1; y > 0; y--)
+			{
+				if (m_NoiseArray[x + 17 * z + 17 * 17 * y] > m_AirThreshold)
+				{
+					// "air" part
+					LastAir = y;
+					if (y < m_SeaLevel)
+					{
+						a_ChunkDesc.SetBlockType(x, y, z, E_BLOCK_STATIONARY_WATER);
+						HasHadWater = true;
+					}
+					continue;
+				}
+				// "ground" part:
+				if (LastAir - y > 4)
+				{
+					a_ChunkDesc.SetBlockType(x, y, z, E_BLOCK_STONE);
+					continue;
+				}
+				if (HasHadWater)
+				{
+					a_ChunkDesc.SetBlockType(x, y, z, E_BLOCK_SAND);
+				}
+				else
+				{
+					a_ChunkDesc.SetBlockType(x, y, z, (LastAir == y + 1) ? E_BLOCK_GRASS : E_BLOCK_DIRT);
+				}
+			}  // for y
+			a_ChunkDesc.SetBlockType(x, 0, z, E_BLOCK_BEDROCK);
+		}  // for x
+	}  // for z
+}
+
+
+
+

src/Generating/Noise3DGenerator.h

@@ -0,0 +1,106 @@
+
+// Noise3DGenerator.h
+
+// Generates terrain using 3D noise, rather than composing. Is a test.
+
+
+
+
+#pragma once
+
+#include "ComposableGenerator.h"
+#include "../Noise.h"
+
+
+
+
+
+class cNoise3DGenerator :
+	public cChunkGenerator::cGenerator
+{
+	typedef cChunkGenerator::cGenerator super;
+	
+public:
+	cNoise3DGenerator(cChunkGenerator & a_ChunkGenerator);
+	virtual ~cNoise3DGenerator();
+	
+	virtual void Initialize(cWorld * a_World, cIniFile & a_IniFile) override;
+	virtual void GenerateBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap) override;
+	virtual void DoGenerate(int a_ChunkX, int a_ChunkZ, cChunkDesc & a_ChunkDesc) override;
+	
+protected:
+	// Linear interpolation step sizes, must be divisors of cChunkDef::Width and cChunkDef::Height, respectively:
+	static const int UPSCALE_X = 8;
+	static const int UPSCALE_Y = 4;
+	static const int UPSCALE_Z = 8;
+	
+	// Linear interpolation buffer dimensions, calculated from the step sizes:
+	static const int DIM_X = 1 + cChunkDef::Width  / UPSCALE_X;
+	static const int DIM_Y = 1 + cChunkDef::Height / UPSCALE_Y;
+	static const int DIM_Z = 1 + cChunkDef::Width  / UPSCALE_Z;
+
+	cPerlinNoise m_Perlin;   // The base 3D noise source for the actual composition
+	cCubicNoise  m_Cubic;    // The noise used for heightmap directing
+	
+	int            m_SeaLevel;
+	NOISE_DATATYPE m_HeightAmplification;
+	NOISE_DATATYPE m_MidPoint;  // Where the vertical "center" of the noise should be
+	NOISE_DATATYPE m_FrequencyX;
+	NOISE_DATATYPE m_FrequencyY;
+	NOISE_DATATYPE m_FrequencyZ;
+	NOISE_DATATYPE m_AirThreshold;
+	
+	/// Generates the 3D noise array used for terrain generation; a_Noise is of ChunkData-size
+	void GenerateNoiseArray(int a_ChunkX, int a_ChunkZ, NOISE_DATATYPE * a_Noise);
+	
+	/// Updates heightmap based on the chunk's contents
+	void UpdateHeightmap(cChunkDesc & a_ChunkDesc);
+	
+	/// Composes terrain - adds dirt, grass and sand
+	void ComposeTerrain(cChunkDesc & a_ChunkDesc);
+} ;
+
+
+
+
+
+class cNoise3DComposable :
+	public cTerrainHeightGen,
+	public cTerrainCompositionGen
+{
+public:
+	cNoise3DComposable(int a_Seed);
+
+	void Initialize(cIniFile & a_IniFile);
+
+protected:
+	cNoise m_Noise1;
+	cNoise m_Noise2;
+	cNoise m_Noise3;
+	
+	int            m_SeaLevel;
+	NOISE_DATATYPE m_HeightAmplification;
+	NOISE_DATATYPE m_MidPoint;  // Where the vertical "center" of the noise should be
+	NOISE_DATATYPE m_FrequencyX;
+	NOISE_DATATYPE m_FrequencyY;
+	NOISE_DATATYPE m_FrequencyZ;
+	NOISE_DATATYPE m_AirThreshold;
+	
+	int m_LastChunkX;
+	int m_LastChunkZ;
+	NOISE_DATATYPE m_NoiseArray[17 * 17 * 257];  // x + 17 * z + 17 * 17 * y
+	
+	
+	/// Generates the 3D noise array used for terrain generation, unless the LastChunk coords are equal to coords given
+	void GenerateNoiseArrayIfNeeded(int a_ChunkX, int a_ChunkZ);
+	
+	// cTerrainHeightGen overrides:
+	virtual void GenHeightMap(int a_ChunkX, int a_ChunkZ, cChunkDef::HeightMap & a_HeightMap) override;
+
+	// cTerrainCompositionGen overrides:
+	virtual void ComposeTerrain(cChunkDesc & a_ChunkDesc) override;
+} ;
+
+
+
+

src/Generating/Ravines.cpp

@@ -0,0 +1,531 @@
+
+// Ravines.cpp
+
+// Implements the cStructGenRavines class representing the ravine structure generator
+
+#include "Globals.h"
+#include "Ravines.h"
+
+
+
+
+/// How many ravines in each direction are generated for a given chunk. Must be an even number
+static const int NEIGHBORHOOD_SIZE = 8;
+
+static const int NUM_RAVINE_POINTS = 4;
+
+
+
+
+
+struct cRavDefPoint
+{
+	int m_BlockX;
+	int m_BlockZ;
+	int m_Radius;
+	int m_Top;
+	int m_Bottom;
+	
+	cRavDefPoint(int a_BlockX, int a_BlockZ, int a_Radius, int a_Top, int a_Bottom) :
+		m_BlockX(a_BlockX),
+		m_BlockZ(a_BlockZ),
+		m_Radius(a_Radius),
+		m_Top   (a_Top),
+		m_Bottom(a_Bottom)
+	{
+	}
+} ;
+
+typedef std::vector<cRavDefPoint> cRavDefPoints;
+
+
+
+
+
+class cStructGenRavines::cRavine
+{
+	cRavDefPoints m_Points;
+	
+	/// Generates the shaping defpoints for the ravine, based on the ravine block coords and noise
+	void GenerateBaseDefPoints(int a_BlockX, int a_BlockZ, int a_Size, cNoise & a_Noise);
+	
+	/// Refines (adds and smooths) defpoints from a_Src into a_Dst
+	void RefineDefPoints(const cRavDefPoints & a_Src, cRavDefPoints & a_Dst);
+	
+	/// Does one round of smoothing, two passes of RefineDefPoints()
+	void Smooth(void);
+	
+	/// Linearly interpolates the points so that the maximum distance between two neighbors is max 1 block
+	void FinishLinear(void);
+	
+public:
+	// Coords for which the ravine was generated (not necessarily the center)
+	int m_BlockX;
+	int m_BlockZ;
+	
+	cRavine(int a_BlockX, int a_BlockZ, int a_Size, cNoise & a_Noise);
+	
+	/// Carves the ravine into the chunk specified
+	void ProcessChunk(
+		int a_ChunkX, int a_ChunkZ, 
+		cChunkDef::BlockTypes & a_BlockTypes, 
+		cChunkDef::HeightMap & a_HeightMap
+	);
+	
+	#ifdef _DEBUG
+	/// Exports itself as a SVG line definition
+	AString ExportAsSVG(int a_Color, int a_OffsetX = 0, int a_OffsetZ = 0) const;
+	#endif  // _DEBUG
+} ;
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cStructGenRavines:
+
+cStructGenRavines::cStructGenRavines(int a_Seed, int a_Size) :
+	m_Noise(a_Seed),
+	m_Size(a_Size)
+{
+}
+
+
+
+
+
+cStructGenRavines::~cStructGenRavines()
+{
+	ClearCache();
+}
+
+
+
+
+
+void cStructGenRavines::ClearCache(void)
+{
+	for (cRavines::const_iterator itr = m_Cache.begin(), end = m_Cache.end(); itr != end; ++itr)
+	{
+		delete *itr;
+	}  // for itr - m_Cache[]
+	m_Cache.clear();
+}
+
+
+
+
+
+void cStructGenRavines::GenStructures(cChunkDesc & a_ChunkDesc)
+{
+	int ChunkX = a_ChunkDesc.GetChunkX();
+	int ChunkZ = a_ChunkDesc.GetChunkZ();
+	cRavines Ravines;
+	GetRavinesForChunk(ChunkX, ChunkZ, Ravines);
+	for (cRavines::const_iterator itr = Ravines.begin(), end = Ravines.end(); itr != end; ++itr)
+	{
+		(*itr)->ProcessChunk(ChunkX, ChunkZ, a_ChunkDesc.GetBlockTypes(), a_ChunkDesc.GetHeightMap());
+	}  // for itr - Ravines[]
+}
+
+
+
+
+
+void cStructGenRavines::GetRavinesForChunk(int a_ChunkX, int a_ChunkZ, cStructGenRavines::cRavines & a_Ravines)
+{
+	int BaseX = a_ChunkX * cChunkDef::Width / m_Size;
+	int BaseZ = a_ChunkZ * cChunkDef::Width / m_Size;
+	if (BaseX < 0)
+	{
+		--BaseX;
+	}
+	if (BaseZ < 0)
+	{
+		--BaseZ;
+	}
+	BaseX -= 4;
+	BaseZ -= 4;
+	
+	// Walk the cache, move each ravine that we want into a_Ravines:
+	int StartX = BaseX * m_Size;
+	int EndX = (BaseX + NEIGHBORHOOD_SIZE + 1) * m_Size;
+	int StartZ = BaseZ * m_Size;
+	int EndZ = (BaseZ + NEIGHBORHOOD_SIZE + 1) * m_Size;
+	for (cRavines::iterator itr = m_Cache.begin(), end = m_Cache.end(); itr != end;)
+	{
+		if (
+			((*itr)->m_BlockX >= StartX) && ((*itr)->m_BlockX < EndX) &&
+			((*itr)->m_BlockZ >= StartZ) && ((*itr)->m_BlockZ < EndZ)
+		)
+		{
+			// want
+			a_Ravines.push_back(*itr);
+			itr = m_Cache.erase(itr);
+		}
+		else
+		{
+			// don't want
+			++itr;
+		}
+	}  // for itr - m_Cache[]
+	
+	for (int x = 0; x < NEIGHBORHOOD_SIZE; x++)
+	{
+		int RealX = (BaseX + x) * m_Size;
+		for (int z = 0; z < NEIGHBORHOOD_SIZE; z++)
+		{
+			int RealZ = (BaseZ + z) * m_Size;
+			bool Found = false;
+			for (cRavines::const_iterator itr = a_Ravines.begin(), end = a_Ravines.end(); itr != end; ++itr)
+			{
+				if (((*itr)->m_BlockX == RealX) && ((*itr)->m_BlockZ == RealZ))
+				{
+					Found = true;
+					break;
+				}
+			}
+			if (!Found)
+			{
+				a_Ravines.push_back(new cRavine(RealX, RealZ, m_Size, m_Noise));
+			}
+		}
+	}
+	
+	// Copy a_Ravines into m_Cache to the beginning:
+	cRavines RavinesCopy(a_Ravines);
+	m_Cache.splice(m_Cache.begin(), RavinesCopy, RavinesCopy.begin(), RavinesCopy.end());
+	
+	// Trim the cache if it's too long:
+	if (m_Cache.size() > 100)
+	{
+		cRavines::iterator itr = m_Cache.begin();
+		std::advance(itr, 100);
+		for (cRavines::iterator end = m_Cache.end(); itr != end; ++itr)
+		{
+			delete *itr;
+		}
+		itr = m_Cache.begin();
+		std::advance(itr, 100);
+		m_Cache.erase(itr, m_Cache.end());
+	}
+	
+	/*
+	#ifdef _DEBUG
+	// DEBUG: Export as SVG into a file specific for the chunk, for visual verification:
+	AString SVG;
+	SVG.append("<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>\n<svg xmlns=\"http://www.w3.org/2000/svg\" width=\"1024\" height = \"1024\">\n");
+	for (cRavines::const_iterator itr = a_Ravines.begin(), end = a_Ravines.end(); itr != end; ++itr)
+	{
+		SVG.append((*itr)->ExportAsSVG(0, 512, 512));
+	}
+	SVG.append("</svg>\n");
+	
+	AString fnam;
+	Printf(fnam, "ravines\\%03d_%03d.svg", a_ChunkX, a_ChunkZ);
+	cFile File(fnam, cFile::fmWrite);
+	File.Write(SVG.c_str(), SVG.size());
+	#endif  // _DEBUG
+	//*/
+}
+
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cStructGenRavines::cRavine
+
+cStructGenRavines::cRavine::cRavine(int a_BlockX, int a_BlockZ, int a_Size, cNoise & a_Noise) :
+	m_BlockX(a_BlockX),
+	m_BlockZ(a_BlockZ)
+{
+	// Calculate the ravine shape-defining points:
+	GenerateBaseDefPoints(a_BlockX, a_BlockZ, a_Size, a_Noise);
+	
+	// Smooth the ravine. A two passes are needed:
+	Smooth();
+	Smooth();
+	
+	// Linearly interpolate the neighbors so that they're close enough together:
+	FinishLinear();
+}
+
+
+
+
+
+void cStructGenRavines::cRavine::GenerateBaseDefPoints(int a_BlockX, int a_BlockZ, int a_Size, cNoise & a_Noise)
+{
+	// Modify the size slightly to have different-sized ravines (1/2 to 1/1 of a_Size):
+	a_Size = (512 + ((a_Noise.IntNoise3DInt(19 * a_BlockX, 11 * a_BlockZ, a_BlockX + a_BlockZ) / 17) % 512)) * a_Size / 1024;
+	
+	// The complete offset of the ravine from its cellpoint, up to 2 * a_Size in each direction
+	int OffsetX = (((a_Noise.IntNoise3DInt(50 * a_BlockX, 30 * a_BlockZ, 0)    / 9) % (2 * a_Size)) + ((a_Noise.IntNoise3DInt(30 * a_BlockX, 50 * m_BlockZ, 1000) / 7) % (2 * a_Size)) - 2 * a_Size) / 2;
+	int OffsetZ = (((a_Noise.IntNoise3DInt(50 * a_BlockX, 30 * a_BlockZ, 2000) / 7) % (2 * a_Size)) + ((a_Noise.IntNoise3DInt(30 * a_BlockX, 50 * m_BlockZ, 3000) / 9) % (2 * a_Size)) - 2 * a_Size) / 2;
+	int CenterX = a_BlockX + OffsetX;
+	int CenterZ = a_BlockZ + OffsetZ;
+	
+	// Get the base angle in which the ravine "axis" goes:
+	float Angle = (float)(((float)((a_Noise.IntNoise3DInt(20 * a_BlockX, 70 * a_BlockZ, 6000) / 9) % 16384)) / 16384.0 * 3.141592653);
+	float xc = sin(Angle);
+	float zc = cos(Angle);
+	
+	// Calculate the definition points and radii:
+	int MaxRadius = (int)(sqrt(12.0 + ((a_Noise.IntNoise2DInt(61 * a_BlockX, 97 * a_BlockZ) / 13) % a_Size) / 16));
+	int Top       = 32 + ((a_Noise.IntNoise2DInt(13 * a_BlockX, 17 * a_BlockZ) / 23) % 32);
+	int Bottom    = 5 + ((a_Noise.IntNoise2DInt(17 * a_BlockX, 29 * a_BlockZ) / 13) % 32);
+	int Mid = (Top + Bottom) / 2;
+	int PointX = CenterX - (int)(xc * a_Size / 2);
+	int PointZ = CenterZ - (int)(zc * a_Size / 2);
+	m_Points.push_back(cRavDefPoint(PointX, PointZ, 0, (Mid + Top) / 2, (Mid + Bottom) / 2));
+	for (int i = 1; i < NUM_RAVINE_POINTS - 1; i++)
+	{
+		int LineX = CenterX + (int)(xc * a_Size * (i - NUM_RAVINE_POINTS / 2) / NUM_RAVINE_POINTS);
+		int LineZ = CenterZ + (int)(zc * a_Size * (i - NUM_RAVINE_POINTS / 2) / NUM_RAVINE_POINTS);
+		// Amplitude is the amount of blocks that this point is away from the ravine "axis"
+		int Amplitude = (a_Noise.IntNoise3DInt(70 * a_BlockX, 20 * a_BlockZ + 31 * i, 10000 * i) / 9) % a_Size;
+		Amplitude = Amplitude / 4 - a_Size / 8;  // Amplitude is in interval [-a_Size / 4, a_Size / 4]
+		int PointX = LineX + (int)(zc * Amplitude);
+		int PointZ = LineZ - (int)(xc * Amplitude);
+		int Radius = MaxRadius - abs(i - NUM_RAVINE_POINTS / 2);  // TODO: better radius function
+		int ThisTop    = Top    + ((a_Noise.IntNoise3DInt(7 *  a_BlockX, 19 * a_BlockZ, i * 31) / 13) % 8) - 4;
+		int ThisBottom = Bottom + ((a_Noise.IntNoise3DInt(19 * a_BlockX, 7 *  a_BlockZ, i * 31) / 13) % 8) - 4;
+		m_Points.push_back(cRavDefPoint(PointX, PointZ, Radius, ThisTop, ThisBottom));
+	}  // for i - m_Points[]
+	PointX = CenterX + (int)(xc * a_Size / 2);
+	PointZ = CenterZ + (int)(zc * a_Size / 2);
+	m_Points.push_back(cRavDefPoint(PointX, PointZ, 0, Mid, Mid));
+}
+
+
+
+
+
+void cStructGenRavines::cRavine::RefineDefPoints(const cRavDefPoints & a_Src, cRavDefPoints & a_Dst)
+{
+	// Smoothing: for each line segment, add points on its 1/4 lengths
+	int Num = a_Src.size() - 2;  // this many intermediary points
+	a_Dst.clear();
+	a_Dst.reserve(Num * 2 + 2);
+	cRavDefPoints::const_iterator itr = a_Src.begin() + 1;
+	a_Dst.push_back(a_Src.front());
+	int PrevX = a_Src.front().m_BlockX;
+	int PrevZ = a_Src.front().m_BlockZ;
+	int PrevR = a_Src.front().m_Radius;
+	int PrevT = a_Src.front().m_Top;
+	int PrevB = a_Src.front().m_Bottom;
+	for (int i = 0; i <= Num; ++i, ++itr)
+	{
+		int dx = itr->m_BlockX - PrevX;
+		int dz = itr->m_BlockZ - PrevZ;
+		if (abs(dx) + abs(dz) < 4)
+		{
+			// Too short a segment to smooth-subdivide into quarters
+			continue;
+		}
+		int dr = itr->m_Radius - PrevR;
+		int dt = itr->m_Top    - PrevT;
+		int db = itr->m_Bottom - PrevB;
+		int Rad1 = std::max(PrevR + 1 * dr / 4, 1);
+		int Rad2 = std::max(PrevR + 3 * dr / 4, 1);
+		a_Dst.push_back(cRavDefPoint(PrevX + 1 * dx / 4, PrevZ + 1 * dz / 4, Rad1, PrevT + 1 * dt / 4, PrevB + 1 * db / 4));
+		a_Dst.push_back(cRavDefPoint(PrevX + 3 * dx / 4, PrevZ + 3 * dz / 4, Rad2, PrevT + 3 * dt / 4, PrevB + 3 * db / 4));
+		PrevX = itr->m_BlockX;
+		PrevZ = itr->m_BlockZ;
+		PrevR = itr->m_Radius;
+		PrevT = itr->m_Top;
+		PrevB = itr->m_Bottom;
+	}
+	a_Dst.push_back(a_Src.back());
+}
+
+
+
+
+
+void cStructGenRavines::cRavine::Smooth(void)
+{
+	cRavDefPoints Pts;
+	RefineDefPoints(m_Points, Pts);  // Refine m_Points -> Pts
+	RefineDefPoints(Pts, m_Points);  // Refine Pts -> m_Points
+}
+
+
+
+
+
+void cStructGenRavines::cRavine::FinishLinear(void)
+{
+	// For each segment, use Bresenham's line algorithm to draw a "line" of defpoints
+	// _X 2012_07_20: I tried modifying this algorithm to produce "thick" lines (only one coord change per point)
+	//   But the results were about the same as the original, so I disposed of it again - no need to use twice the count of points
+	
+	cRavDefPoints Pts;
+	std::swap(Pts, m_Points);
+	
+	m_Points.reserve(Pts.size() * 3);
+	int PrevX = Pts.front().m_BlockX;
+	int PrevZ = Pts.front().m_BlockZ;
+	for (cRavDefPoints::const_iterator itr = Pts.begin() + 1, end = Pts.end(); itr != end; ++itr)
+	{
+		int x1 = itr->m_BlockX;
+		int z1 = itr->m_BlockZ;
+		int dx = abs(x1 - PrevX);
+		int dz = abs(z1 - PrevZ);
+		int sx = (PrevX < x1) ? 1 : -1;
+		int sz = (PrevZ < z1) ? 1 : -1;
+		int err = dx - dz;
+		int R = itr->m_Radius;
+		int T = itr->m_Top;
+		int B = itr->m_Bottom;
+		while (true)
+		{
+			m_Points.push_back(cRavDefPoint(PrevX, PrevZ, R, T, B));
+			if ((PrevX == x1) && (PrevZ == z1))
+			{
+				break;
+			}
+			int e2 = 2 * err;
+			if (e2 > -dz)
+			{
+				err -= dz;
+				PrevX += sx;
+			}
+			if (e2 < dx)
+			{
+				err += dx;
+				PrevZ += sz;
+			}
+		}  // while (true)
+	}  // for itr
+}
+
+
+
+
+
+#ifdef _DEBUG
+AString cStructGenRavines::cRavine::ExportAsSVG(int a_Color, int a_OffsetX, int a_OffsetZ) const
+{
+	AString SVG;
+  AppendPrintf(SVG, "<path style=\"fill:none;stroke:#%06x;stroke-width:1px;\"\nd=\"", a_Color);
+  char Prefix = 'M';  // The first point needs "M" prefix, all the others need "L"
+  for (cRavDefPoints::const_iterator itr = m_Points.begin(); itr != m_Points.end(); ++itr)
+  {
+		AppendPrintf(SVG, "%c %d,%d ", Prefix, a_OffsetX + itr->m_BlockX, a_OffsetZ + itr->m_BlockZ);
+		Prefix = 'L';
+  }
+  SVG.append("\"/>\n");
+  
+  // Base point highlight:
+  AppendPrintf(SVG, "<path style=\"fill:none;stroke:#ff0000;stroke-width:1px;\"\nd=\"M %d,%d L %d,%d\"/>\n",
+		a_OffsetX + m_BlockX - 5, a_OffsetZ + m_BlockZ, a_OffsetX + m_BlockX + 5, a_OffsetZ + m_BlockZ
+	);
+  AppendPrintf(SVG, "<path style=\"fill:none;stroke:#ff0000;stroke-width:1px;\"\nd=\"M %d,%d L %d,%d\"/>\n",
+		a_OffsetX + m_BlockX, a_OffsetZ + m_BlockZ - 5, a_OffsetX + m_BlockX, a_OffsetZ + m_BlockZ + 5
+	);
+	
+	// A gray line from the base point to the first point of the ravine, for identification:
+  AppendPrintf(SVG, "<path style=\"fill:none;stroke:#cfcfcf;stroke-width:1px;\"\nd=\"M %d,%d L %d,%d\"/>\n",
+		a_OffsetX + m_BlockX, a_OffsetZ + m_BlockZ, a_OffsetX + m_Points.front().m_BlockX, a_OffsetZ + m_Points.front().m_BlockZ
+	);
+	
+	// Offset guides:
+	if (a_OffsetX > 0)
+	{
+		AppendPrintf(SVG, "<path style=\"fill:none;stroke:#0000ff;stroke-width:1px;\"\nd=\"M %d,0 L %d,1024\"/>\n",
+			a_OffsetX, a_OffsetX
+		);
+	}
+	if (a_OffsetZ > 0)
+	{
+		AppendPrintf(SVG, "<path style=\"fill:none;stroke:#0000ff;stroke-width:1px;\"\nd=\"M 0,%d L 1024,%d\"/>\n",
+			a_OffsetZ, a_OffsetZ
+		);
+	}
+	return SVG;
+}
+#endif  // _DEBUG
+
+
+
+
+
+void cStructGenRavines::cRavine::ProcessChunk(
+	int a_ChunkX, int a_ChunkZ, 
+	cChunkDef::BlockTypes & a_BlockTypes,
+	cChunkDef::HeightMap & a_HeightMap
+)
+{
+	int BlockStartX = a_ChunkX * cChunkDef::Width;
+	int BlockStartZ = a_ChunkZ * cChunkDef::Width;
+	int BlockEndX = BlockStartX + cChunkDef::Width;
+	int BlockEndZ = BlockStartZ + cChunkDef::Width;
+	for (cRavDefPoints::const_iterator itr = m_Points.begin(), end = m_Points.end(); itr != end; ++itr)
+	{
+		if (
+			(itr->m_BlockX + itr->m_Radius < BlockStartX) ||
+			(itr->m_BlockX - itr->m_Radius > BlockEndX) ||
+			(itr->m_BlockZ + itr->m_Radius < BlockStartZ) ||
+			(itr->m_BlockZ - itr->m_Radius > BlockEndZ)
+		)
+		{
+			// Cannot intersect, bail out early
+			continue;
+		}
+		
+		// Carve out a cylinder around the xz point, m_Radius in diameter, from Bottom to Top:
+		int RadiusSq = itr->m_Radius * itr->m_Radius;  // instead of doing sqrt for each distance, we do sqr of the radius
+		int DifX = BlockStartX - itr->m_BlockX;  // substitution for faster calc
+		int DifZ = BlockStartZ - itr->m_BlockZ;  // substitution for faster calc
+		for (int x = 0; x < cChunkDef::Width; x++) for (int z = 0; z < cChunkDef::Width; z++)
+		{
+			#ifdef _DEBUG
+			// DEBUG: Make the ravine shapepoints visible on a single layer (so that we can see with Minutor what's going on)
+			if ((DifX + x == 0) && (DifZ + z == 0))
+			{
+				cChunkDef::SetBlock(a_BlockTypes, x, 4, z, E_BLOCK_LAPIS_ORE);
+			}
+			#endif  // _DEBUG
+			
+			int DistSq = (DifX + x) * (DifX + x) + (DifZ + z) * (DifZ + z);
+			if (DistSq <= RadiusSq)
+			{
+				int Top = std::min(itr->m_Top, (int)(cChunkDef::Height));  // Stupid gcc needs int cast
+				for (int y = std::max(itr->m_Bottom, 1); y <= Top; y++)
+				{
+					switch (cChunkDef::GetBlock(a_BlockTypes, x, y, z))
+					{
+						// Only carve out these specific block types
+						case E_BLOCK_DIRT:
+						case E_BLOCK_GRASS:
+						case E_BLOCK_STONE:
+						case E_BLOCK_COBBLESTONE:
+						case E_BLOCK_GRAVEL:
+						case E_BLOCK_SAND:
+						case E_BLOCK_SANDSTONE:
+						case E_BLOCK_NETHERRACK:
+						case E_BLOCK_COAL_ORE:
+						case E_BLOCK_IRON_ORE:
+						case E_BLOCK_GOLD_ORE:
+						case E_BLOCK_DIAMOND_ORE:
+						case E_BLOCK_REDSTONE_ORE:
+						case E_BLOCK_REDSTONE_ORE_GLOWING:
+						{
+							cChunkDef::SetBlock(a_BlockTypes, x, y, z, E_BLOCK_AIR);
+							break;
+						}
+						default: break;
+					}
+				}
+			}
+		}  // for x, z - a_BlockTypes
+	}  // for itr - m_Points[]
+}
+
+
+
+

src/Generating/Ravines.h

@@ -0,0 +1,46 @@
+
+// Ravines.h
+
+// Interfaces to the cStructGenRavines class representing the ravine structure generator
+
+
+
+
+
+#pragma once
+
+#include "ComposableGenerator.h"
+#include "../Noise.h"
+
+
+
+
+
+class cStructGenRavines :
+	public cStructureGen
+{
+public:
+	cStructGenRavines(int a_Seed, int a_Size);
+	~cStructGenRavines();
+	
+protected:
+	class cRavine;  // fwd: Ravines.cpp
+	typedef std::list<cRavine *> cRavines;
+	
+	cNoise   m_Noise;
+	int      m_Size;  // Max size, in blocks, of the ravines generated
+	cRavines m_Cache;
+	
+	/// Clears everything from the cache
+	void ClearCache(void);
+	
+	/// Returns all ravines that *may* intersect the given chunk. All the ravines are valid until the next call to this function.
+	void GetRavinesForChunk(int a_ChunkX, int a_ChunkZ, cRavines & a_Ravines);
+	
+	// cStructureGen override:
+	virtual void GenStructures(cChunkDesc & a_ChunkDesc) override;
+} ;
+
+
+
+

src/Generating/StructGen.cpp

@@ -0,0 +1,675 @@
+
+// StructGen.h
+
+#include "Globals.h"
+#include "StructGen.h"
+#include "../BlockID.h"
+#include "Trees.h"
+#include "../BlockArea.h"
+#include "../LinearUpscale.h"
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cStructGenOreNests configuration:
+
+const int MAX_HEIGHT_COAL = 127;
+const int NUM_NESTS_COAL = 50;
+const int NEST_SIZE_COAL = 10;
+
+const int MAX_HEIGHT_IRON = 64;
+const int NUM_NESTS_IRON = 14;
+const int NEST_SIZE_IRON = 6;
+
+const int MAX_HEIGHT_REDSTONE = 16;
+const int NUM_NESTS_REDSTONE = 4;
+const int NEST_SIZE_REDSTONE = 6;
+
+const int MAX_HEIGHT_GOLD = 32;
+const int NUM_NESTS_GOLD = 2;
+const int NEST_SIZE_GOLD = 6;
+
+const int MAX_HEIGHT_DIAMOND = 15;
+const int NUM_NESTS_DIAMOND = 1;
+const int NEST_SIZE_DIAMOND = 4;
+
+const int MAX_HEIGHT_LAPIS = 30;
+const int NUM_NESTS_LAPIS = 2;
+const int NEST_SIZE_LAPIS = 5;
+
+const int MAX_HEIGHT_DIRT = 127;
+const int NUM_NESTS_DIRT = 20;
+const int NEST_SIZE_DIRT = 32;
+
+const int MAX_HEIGHT_GRAVEL = 70;
+const int NUM_NESTS_GRAVEL = 15;
+const int NEST_SIZE_GRAVEL = 32;
+
+
+
+
+
+template <typename T> T Clamp(T a_Value, T a_Min, T a_Max)
+{
+	return (a_Value < a_Min) ? a_Min : ((a_Value > a_Max) ? a_Max : a_Value);
+}
+
+
+
+
+
+static bool SortTreeBlocks(const sSetBlock & a_First, const sSetBlock & a_Second)
+{
+	return (a_First.BlockType == E_BLOCK_LOG) && (a_Second.BlockType != E_BLOCK_LOG);
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cStructGenTrees:
+
+void cStructGenTrees::GenStructures(cChunkDesc & a_ChunkDesc)
+{
+	int ChunkX = a_ChunkDesc.GetChunkX();
+	int ChunkZ = a_ChunkDesc.GetChunkZ();
+	
+	cChunkDesc WorkerDesc(ChunkX, ChunkZ);
+	
+	// Generate trees:
+	for (int x = 0; x <= 2; x++)
+	{
+		int BaseX = ChunkX + x - 1;
+		for (int z = 0; z <= 2; z++)
+		{
+			int BaseZ = ChunkZ + z - 1;
+			
+			cChunkDesc * Dest;
+
+			if ((x != 1) || (z != 1))
+			{
+				Dest = &WorkerDesc;
+				WorkerDesc.SetChunkCoords(BaseX, BaseZ);
+				
+				m_BiomeGen->GenBiomes           (BaseX, BaseZ, WorkerDesc.GetBiomeMap());
+				m_HeightGen->GenHeightMap       (BaseX, BaseZ, WorkerDesc.GetHeightMap());
+				m_CompositionGen->ComposeTerrain(WorkerDesc);
+				// TODO: Free the entity lists
+			}
+			else
+			{
+				Dest = &a_ChunkDesc;
+			}
+
+			int NumTrees = GetNumTrees(BaseX, BaseZ, Dest->GetBiomeMap());
+
+			sSetBlockVector OutsideLogs, OutsideOther;
+			for (int i = 0; i < NumTrees; i++)
+			{
+				GenerateSingleTree(BaseX, BaseZ, i, *Dest, OutsideLogs, OutsideOther);
+			}
+
+			sSetBlockVector IgnoredOverflow;
+			IgnoredOverflow.reserve(OutsideOther.size());
+			ApplyTreeImage(ChunkX, ChunkZ, a_ChunkDesc, OutsideOther, IgnoredOverflow);
+			IgnoredOverflow.clear();
+			IgnoredOverflow.reserve(OutsideLogs.size());
+			ApplyTreeImage(ChunkX, ChunkZ, a_ChunkDesc, OutsideLogs, IgnoredOverflow);
+		}  // for z
+	}  // for x
+	
+	// Update the heightmap:
+	for (int x = 0; x < cChunkDef::Width; x++)
+	{
+		for (int z = 0; z < cChunkDef::Width; z++)
+		{
+			for (int y = cChunkDef::Height - 1; y >= 0; y--)
+			{
+				if (a_ChunkDesc.GetBlockType(x, y, z) != E_BLOCK_AIR)
+				{
+					a_ChunkDesc.SetHeight(x, z, y);
+					break;
+				}
+			}  // for y
+		}  // for z
+	}  // for x
+}
+
+
+
+
+
+void cStructGenTrees::GenerateSingleTree(
+	int a_ChunkX, int a_ChunkZ, int a_Seq,
+	cChunkDesc & a_ChunkDesc,
+	sSetBlockVector & a_OutsideLogs,
+	sSetBlockVector & a_OutsideOther
+)
+{
+	int x = (m_Noise.IntNoise3DInt(a_ChunkX + a_ChunkZ, a_ChunkZ, a_Seq) / 19) % cChunkDef::Width;
+	int z = (m_Noise.IntNoise3DInt(a_ChunkX - a_ChunkZ, a_Seq, a_ChunkZ) / 19) % cChunkDef::Width;
+	
+	int Height = a_ChunkDesc.GetHeight(x, z);
+	
+	if ((Height <= 0) || (Height > 240))
+	{
+		return;
+	}
+
+	// Check the block underneath the tree:
+	BLOCKTYPE TopBlock = a_ChunkDesc.GetBlockType(x, Height, z);
+	if ((TopBlock != E_BLOCK_DIRT) && (TopBlock != E_BLOCK_GRASS) && (TopBlock != E_BLOCK_FARMLAND))
+	{
+		return;
+	}
+	
+	sSetBlockVector TreeLogs, TreeOther;
+	GetTreeImageByBiome(
+		a_ChunkX * cChunkDef::Width + x, Height + 1, a_ChunkZ * cChunkDef::Width + z,
+		m_Noise, a_Seq, 
+		a_ChunkDesc.GetBiome(x, z),
+		TreeLogs, TreeOther
+	);
+
+	// Check if the generated image fits the terrain. Only the logs are checked:
+	for (sSetBlockVector::const_iterator itr = TreeLogs.begin(); itr != TreeLogs.end(); ++itr)
+	{
+		if ((itr->ChunkX != a_ChunkX) || (itr->ChunkZ != a_ChunkZ))
+		{
+			// Outside the chunk
+			continue;
+		}
+
+		BLOCKTYPE Block = a_ChunkDesc.GetBlockType(itr->x, itr->y, itr->z);
+		switch (Block)
+		{
+			CASE_TREE_ALLOWED_BLOCKS:
+			{
+				break;
+			}
+			default:
+			{
+				// There's something in the way, abort this tree altogether
+				return;
+			}
+		}
+	}
+	
+	ApplyTreeImage(a_ChunkX, a_ChunkZ, a_ChunkDesc, TreeOther, a_OutsideOther);
+	ApplyTreeImage(a_ChunkX, a_ChunkZ, a_ChunkDesc, TreeLogs,  a_OutsideLogs);	
+}
+
+
+
+
+
+void cStructGenTrees::ApplyTreeImage(
+	int a_ChunkX, int a_ChunkZ,
+	cChunkDesc & a_ChunkDesc,
+	const sSetBlockVector & a_Image,
+	sSetBlockVector & a_Overflow
+)
+{
+	// Put the generated image into a_BlockTypes, push things outside this chunk into a_Blocks
+	for (sSetBlockVector::const_iterator itr = a_Image.begin(), end = a_Image.end(); itr != end; ++itr)
+	{
+		if ((itr->ChunkX == a_ChunkX) && (itr->ChunkZ == a_ChunkZ))
+		{
+			// Inside this chunk, integrate into a_ChunkDesc:
+			switch (a_ChunkDesc.GetBlockType(itr->x, itr->y, itr->z))
+			{
+				case E_BLOCK_LEAVES:
+				{
+					if (itr->BlockType != E_BLOCK_LOG)
+					{
+						break;
+					}
+					// fallthrough:
+				}
+				CASE_TREE_OVERWRITTEN_BLOCKS:
+				{
+					a_ChunkDesc.SetBlockTypeMeta(itr->x, itr->y, itr->z, itr->BlockType, itr->BlockMeta);
+					break;
+				}
+				
+			}  // switch (GetBlock())
+			continue;
+		}
+		
+		// Outside the chunk, push into a_Overflow.
+		// Don't check if already present there, by separating logs and others we don't need the checks anymore:
+		a_Overflow.push_back(*itr);
+	}
+}
+
+
+
+
+
+int cStructGenTrees::GetNumTrees(
+	int a_ChunkX, int a_ChunkZ,
+	const cChunkDef::BiomeMap & a_Biomes
+)
+{
+	int NumTrees = 0;
+	for (int x = 0; x < cChunkDef::Width; x++) for (int z = 0; z < cChunkDef::Width; z++)
+	{
+		int Add = 0;
+		switch (cChunkDef::GetBiome(a_Biomes, x, z))
+		{
+			case biPlains:           Add =   1; break;
+			case biExtremeHills:     Add =   3; break;
+			case biForest:           Add =  30; break;
+			case biTaiga:            Add =  30; break;
+			case biSwampland:        Add =   8; break;
+			case biIcePlains:        Add =   1; break;
+			case biIceMountains:     Add =   1; break;
+			case biMushroomIsland:   Add =   3; break;
+			case biMushroomShore:    Add =   3; break;
+			case biForestHills:      Add =  20; break;
+			case biTaigaHills:       Add =  20; break;
+			case biExtremeHillsEdge: Add =   5; break;
+			case biJungle:           Add = 120; break;
+			case biJungleHills:      Add =  90; break;
+		}
+		NumTrees += Add;
+	}
+	return NumTrees / 1024;
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cStructGenOreNests:
+
+void cStructGenOreNests::GenStructures(cChunkDesc & a_ChunkDesc)
+{
+	int ChunkX = a_ChunkDesc.GetChunkX();
+	int ChunkZ = a_ChunkDesc.GetChunkZ();
+	cChunkDef::BlockTypes & BlockTypes = a_ChunkDesc.GetBlockTypes();
+	GenerateOre(ChunkX, ChunkZ, E_BLOCK_COAL_ORE,     MAX_HEIGHT_COAL,     NUM_NESTS_COAL,     NEST_SIZE_COAL,     BlockTypes, 1);
+	GenerateOre(ChunkX, ChunkZ, E_BLOCK_IRON_ORE,     MAX_HEIGHT_IRON,     NUM_NESTS_IRON,     NEST_SIZE_IRON,     BlockTypes, 2);
+	GenerateOre(ChunkX, ChunkZ, E_BLOCK_REDSTONE_ORE, MAX_HEIGHT_REDSTONE, NUM_NESTS_REDSTONE, NEST_SIZE_REDSTONE, BlockTypes, 3);
+	GenerateOre(ChunkX, ChunkZ, E_BLOCK_GOLD_ORE,     MAX_HEIGHT_GOLD,     NUM_NESTS_GOLD,     NEST_SIZE_GOLD,     BlockTypes, 4);
+	GenerateOre(ChunkX, ChunkZ, E_BLOCK_DIAMOND_ORE,  MAX_HEIGHT_DIAMOND,  NUM_NESTS_DIAMOND,  NEST_SIZE_DIAMOND,  BlockTypes, 5);
+	GenerateOre(ChunkX, ChunkZ, E_BLOCK_LAPIS_ORE,    MAX_HEIGHT_LAPIS,    NUM_NESTS_LAPIS,    NEST_SIZE_LAPIS,    BlockTypes, 6);
+	GenerateOre(ChunkX, ChunkZ, E_BLOCK_DIRT,         MAX_HEIGHT_DIRT,     NUM_NESTS_DIRT,     NEST_SIZE_DIRT,     BlockTypes, 10);
+	GenerateOre(ChunkX, ChunkZ, E_BLOCK_GRAVEL,       MAX_HEIGHT_GRAVEL,   NUM_NESTS_GRAVEL,   NEST_SIZE_GRAVEL,   BlockTypes, 11);
+}
+
+
+
+
+
+void cStructGenOreNests::GenerateOre(int a_ChunkX, int a_ChunkZ, BLOCKTYPE a_OreType, int a_MaxHeight, int a_NumNests, int a_NestSize, cChunkDef::BlockTypes & a_BlockTypes, int a_Seq)
+{
+	// This function generates several "nests" of ore, each nest consisting of number of ore blocks relatively adjacent to each other.
+	// It does so by making a random XYZ walk and adding ore along the way in cuboids of different (random) sizes
+	// Only stone gets replaced with ore, all other blocks stay (so the nest can actually be smaller than specified).
+	
+	for (int i = 0; i < a_NumNests; i++)
+	{
+		int rnd = m_Noise.IntNoise3DInt(a_ChunkX + i, a_Seq, a_ChunkZ + 64 * i) / 8;
+		int BaseX = rnd % cChunkDef::Width;
+		rnd /= cChunkDef::Width;
+		int BaseZ = rnd % cChunkDef::Width;
+		rnd /= cChunkDef::Width;
+		int BaseY = rnd % a_MaxHeight;
+		rnd /= a_MaxHeight;
+		int NestSize = a_NestSize + (rnd % (a_NestSize / 4));  // The actual nest size may be up to 1/4 larger
+		int Num = 0;
+		while (Num < NestSize)
+		{
+			// Put a cuboid around [BaseX, BaseY, BaseZ]
+			int rnd = m_Noise.IntNoise3DInt(a_ChunkX + 64 * i, 2 * a_Seq + Num, a_ChunkZ + 32 * i) / 8;
+			int xsize = rnd % 2;
+			int ysize = (rnd / 4) % 2;
+			int zsize = (rnd / 16) % 2;
+			rnd >>= 8;
+			for (int x = xsize; x >= 0; --x)
+			{
+				int BlockX = BaseX + x;
+				if ((BlockX < 0) || (BlockX >= cChunkDef::Width))
+				{
+					Num++;  // So that the cycle finishes even if the base coords wander away from the chunk
+					continue;
+				}
+				for (int y = ysize; y >= 0; --y)
+				{
+					int BlockY = BaseY + y;
+					if ((BlockY < 0) || (BlockY >= cChunkDef::Height))
+					{
+						Num++;  // So that the cycle finishes even if the base coords wander away from the chunk
+						continue;
+					}
+					for (int z = zsize; z >= 0; --z)
+					{
+						int BlockZ = BaseZ + z;
+						if ((BlockZ < 0) || (BlockZ >= cChunkDef::Width))
+						{
+							Num++;  // So that the cycle finishes even if the base coords wander away from the chunk
+							continue;
+						}
+
+						int Index = cChunkDef::MakeIndexNoCheck(BlockX, BlockY, BlockZ);
+						if (a_BlockTypes[Index] == E_BLOCK_STONE)
+						{
+							a_BlockTypes[Index] = a_OreType;
+						}
+						Num++;
+					}  // for z
+				}  // for y
+			}  // for x
+			
+			// Move the base to a neighbor voxel
+			switch (rnd % 4)
+			{
+				case 0: BaseX--; break;
+				case 1: BaseX++; break;
+			}
+			switch ((rnd >> 3) % 4)
+			{
+				case 0: BaseY--; break;
+				case 1: BaseY++; break;
+			}
+			switch ((rnd >> 6) % 4)
+			{
+				case 0: BaseZ--; break;
+				case 1: BaseZ++; break;
+			}
+		}  // while (Num < NumBlocks)
+	}  // for i - NumNests
+}
+
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cStructGenLakes:
+
+void cStructGenLakes::GenStructures(cChunkDesc & a_ChunkDesc)
+{
+	int ChunkX = a_ChunkDesc.GetChunkX();
+	int ChunkZ = a_ChunkDesc.GetChunkZ();
+	
+	for (int z = -1; z < 2; z++) for (int x = -1; x < 2; x++)
+	{
+		if (((m_Noise.IntNoise2DInt(ChunkX + x, ChunkZ + z) / 17) % 100) > m_Probability)
+		{
+			continue;
+		}
+		
+		cBlockArea Lake;
+		CreateLakeImage(ChunkX + x, ChunkZ + z, Lake);
+		
+		int OfsX = Lake.GetOriginX() + x * cChunkDef::Width;
+		int OfsZ = Lake.GetOriginZ() + z * cChunkDef::Width;
+		
+		// Merge the lake into the current data
+		a_ChunkDesc.WriteBlockArea(Lake, OfsX, Lake.GetOriginY(), OfsZ, cBlockArea::msLake);
+	}  // for x, z - neighbor chunks
+}
+
+
+
+
+
+void cStructGenLakes::CreateLakeImage(int a_ChunkX, int a_ChunkZ, cBlockArea & a_Lake)
+{
+	a_Lake.Create(16, 8, 16);
+	a_Lake.Fill(cBlockArea::baTypes, E_BLOCK_SPONGE);  // Sponge is the NOP blocktype for lake merging strategy
+	
+	// Find the minimum height in this chunk:
+	cChunkDef::HeightMap HeightMap;
+	m_HeiGen.GenHeightMap(a_ChunkX, a_ChunkZ, HeightMap);
+	HEIGHTTYPE MinHeight = HeightMap[0];
+	for (int i = 1; i < ARRAYCOUNT(HeightMap); i++)
+	{
+		if (HeightMap[i] < MinHeight)
+		{
+			MinHeight = HeightMap[i];
+		}
+	}
+	
+	// Make a random position in the chunk by using a random 16 block XZ offset and random height up to chunk's max height minus 6
+	MinHeight = std::max(MinHeight - 6, 2);
+	int Rnd = m_Noise.IntNoise3DInt(a_ChunkX, 128, a_ChunkZ) / 11;
+	// Random offset [-8 .. 8], with higher probability around 0; add up four three-bit-wide randoms [0 .. 28], divide and subtract to get range
+	int OffsetX = 4 * ((Rnd & 0x07) + ((Rnd & 0x38) >> 3) + ((Rnd & 0x1c0) >> 6) + ((Rnd & 0xe00) >> 9)) / 7 - 8;
+	Rnd >>= 12;
+	// Random offset [-8 .. 8], with higher probability around 0; add up four three-bit-wide randoms [0 .. 28], divide and subtract to get range
+	int OffsetZ = 4 * ((Rnd & 0x07) + ((Rnd & 0x38) >> 3) + ((Rnd & 0x1c0) >> 6) + ((Rnd & 0xe00) >> 9)) / 7 - 8;
+	Rnd = m_Noise.IntNoise3DInt(a_ChunkX, 512, a_ChunkZ) / 13;
+	// Random height [1 .. MinHeight] with preference to center heights
+	int HeightY = 1 + (((Rnd & 0x1ff) % MinHeight) + (((Rnd >> 9) & 0x1ff) % MinHeight)) / 2;
+	
+	a_Lake.SetOrigin(OffsetX, HeightY, OffsetZ);
+	
+	// Hollow out a few bubbles inside the blockarea:
+	int NumBubbles = 4 + ((Rnd >> 18) & 0x03);  // 4 .. 7 bubbles
+	BLOCKTYPE * BlockTypes = a_Lake.GetBlockTypes();
+	for (int i = 0; i < NumBubbles; i++)
+	{
+		int Rnd = m_Noise.IntNoise3DInt(a_ChunkX, i, a_ChunkZ) / 13;
+		const int BubbleR = 2 + (Rnd & 0x03);  // 2 .. 5
+		const int Range = 16 - 2 * BubbleR;
+		const int BubbleX = BubbleR + (Rnd % Range);
+		Rnd >>= 4;
+		const int BubbleY = 4 + (Rnd & 0x01);  // 4 .. 5
+		Rnd >>= 1;
+		const int BubbleZ = BubbleR + (Rnd % Range);
+		Rnd >>= 4;
+		const int HalfR = BubbleR / 2;  // 1 .. 2
+		const int RSquared = BubbleR * BubbleR;
+		for (int y = -HalfR; y <= HalfR; y++)
+		{
+			// BubbleY + y is in the [0, 7] bounds
+			int DistY = 4 * y * y / 3;
+			int IdxY = (BubbleY + y) * 16 * 16;
+			for (int z = -BubbleR; z <= BubbleR; z++)
+			{
+				int DistYZ = DistY + z * z;
+				if (DistYZ >= RSquared)
+				{
+					continue;
+				}
+				int IdxYZ = BubbleX + IdxY + (BubbleZ + z) * 16;
+				for (int x = -BubbleR; x <= BubbleR; x++) 
+				{
+					if (x * x + DistYZ < RSquared)
+					{
+						BlockTypes[x + IdxYZ] = E_BLOCK_AIR;
+					}
+				}  // for x
+			}  // for z
+		}  // for y
+	}  // for i - bubbles
+
+	// Turn air in the bottom half into liquid:	
+	for (int y = 0; y < 4; y++)
+	{
+		for (int z = 0; z < 16; z++) for (int x = 0; x < 16; x++) 
+		{
+			if (BlockTypes[x + z * 16 + y * 16 * 16] == E_BLOCK_AIR)
+			{
+				BlockTypes[x + z * 16 + y * 16 * 16] = m_Fluid;
+			}
+		}  // for z, x
+	}  // for y
+	
+	// TODO: Turn sponge next to lava into stone
+	
+	// a_Lake.SaveToSchematicFile(Printf("Lake_%d_%d.schematic", a_ChunkX, a_ChunkZ));
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cStructGenDirectOverhangs:
+
+cStructGenDirectOverhangs::cStructGenDirectOverhangs(int a_Seed) :
+	m_Noise1(a_Seed),
+	m_Noise2(a_Seed + 1000)
+{
+}
+
+
+
+
+
+void cStructGenDirectOverhangs::GenStructures(cChunkDesc & a_ChunkDesc)
+{
+	// If there is no column of the wanted biome, bail out:
+	if (!HasWantedBiome(a_ChunkDesc))
+	{
+		return;
+	}
+	
+	HEIGHTTYPE MaxHeight = a_ChunkDesc.GetMaxHeight();
+
+	const int SEGMENT_HEIGHT = 8;
+	const int INTERPOL_X = 16;  // Must be a divisor of 16
+	const int INTERPOL_Z = 16;  // Must be a divisor of 16
+	// Interpolate the chunk in 16 * SEGMENT_HEIGHT * 16 "segments", each SEGMENT_HEIGHT blocks high and each linearly interpolated separately.
+	// Have two buffers, one for the lowest floor and one for the highest floor, so that Y-interpolation can be done between them
+	// Then swap the buffers and use the previously-top one as the current-bottom, without recalculating it.
+	
+	int FloorBuf1[17 * 17];
+	int FloorBuf2[17 * 17];
+	int * FloorHi = FloorBuf1;
+	int * FloorLo = FloorBuf2;
+	int BaseX = a_ChunkDesc.GetChunkX() * cChunkDef::Width;
+	int BaseZ = a_ChunkDesc.GetChunkZ() * cChunkDef::Width;
+	int BaseY = 63;
+	
+	// Interpolate the lowest floor:
+	for (int z = 0; z <= 16 / INTERPOL_Z; z++) for (int x = 0; x <= 16 / INTERPOL_X; x++)
+	{
+		FloorLo[INTERPOL_X * x + 17 * INTERPOL_Z * z] = 
+			m_Noise1.IntNoise3DInt(BaseX + INTERPOL_X * x, BaseY, BaseZ + INTERPOL_Z * z) * 
+			m_Noise2.IntNoise3DInt(BaseX + INTERPOL_X * x, BaseY, BaseZ + INTERPOL_Z * z) /
+			256;
+	}  // for x, z - FloorLo[]
+	LinearUpscale2DArrayInPlace(FloorLo, 17, 17, INTERPOL_X, INTERPOL_Z);
+	
+	// Interpolate segments:
+	for (int Segment = BaseY; Segment < MaxHeight; Segment += SEGMENT_HEIGHT)
+	{
+		// First update the high floor:
+		for (int z = 0; z <= 16 / INTERPOL_Z; z++) for (int x = 0; x <= 16 / INTERPOL_X; x++)
+		{
+			FloorHi[INTERPOL_X * x + 17 * INTERPOL_Z * z] =
+				m_Noise1.IntNoise3DInt(BaseX + INTERPOL_X * x, Segment + SEGMENT_HEIGHT, BaseZ + INTERPOL_Z * z) *
+				m_Noise2.IntNoise3DInt(BaseX + INTERPOL_Z * x, Segment + SEGMENT_HEIGHT, BaseZ + INTERPOL_Z * z) /
+				256;
+		}  // for x, z - FloorLo[]
+		LinearUpscale2DArrayInPlace(FloorHi, 17, 17, INTERPOL_X, INTERPOL_Z);
+		
+		// Interpolate between FloorLo and FloorHi:
+		for (int z = 0; z < 16; z++) for (int x = 0; x < 16; x++)
+		{
+			switch (a_ChunkDesc.GetBiome(x, z))
+			{
+				case biExtremeHills:
+				case biExtremeHillsEdge:
+				{
+					int Lo = FloorLo[x + 17 * z] / 256;
+					int Hi = FloorHi[x + 17 * z] / 256;
+					for (int y = 0; y < SEGMENT_HEIGHT; y++)
+					{
+						int Val = Lo + (Hi - Lo) * y / SEGMENT_HEIGHT;
+						if (Val < 0)
+						{
+							a_ChunkDesc.SetBlockType(x, y + Segment, z, E_BLOCK_AIR);
+						}
+					}  // for y
+					break;
+				}
+			}  // switch (biome)
+		}  // for z, x
+		
+		// Swap the floors:
+		std::swap(FloorLo, FloorHi);
+	}
+}
+
+
+
+
+
+bool cStructGenDirectOverhangs::HasWantedBiome(cChunkDesc & a_ChunkDesc) const
+{
+	cChunkDef::BiomeMap & Biomes = a_ChunkDesc.GetBiomeMap();
+	for (int i = 0; i < ARRAYCOUNT(Biomes); i++)
+	{
+		switch (Biomes[i])
+		{
+			case biExtremeHills:
+			case biExtremeHillsEdge:
+			{
+				return true;
+			}
+		}
+	}  // for i
+	return false;
+}
+
+
+
+
+
+///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+// cStructGenDistortedMembraneOverhangs:
+
+cStructGenDistortedMembraneOverhangs::cStructGenDistortedMembraneOverhangs(int a_Seed) :
+	m_NoiseX(a_Seed + 1000),
+	m_NoiseY(a_Seed + 2000),
+	m_NoiseZ(a_Seed + 3000),
+	m_NoiseH(a_Seed + 4000)
+{
+}
+
+
+
+
+
+void cStructGenDistortedMembraneOverhangs::GenStructures(cChunkDesc & a_ChunkDesc)
+{
+	const NOISE_DATATYPE Frequency = (NOISE_DATATYPE)16;
+	const NOISE_DATATYPE Amount = (NOISE_DATATYPE)1;
+	for (int y = 50; y < 128; y++)
+	{
+		NOISE_DATATYPE NoiseY = (NOISE_DATATYPE)y / 32;
+		// TODO: proper water level - where to get?
+		BLOCKTYPE ReplacementBlock = (y > 62) ? E_BLOCK_AIR : E_BLOCK_STATIONARY_WATER;
+		for (int z = 0; z < cChunkDef::Width; z++)
+		{
+			NOISE_DATATYPE NoiseZ = ((NOISE_DATATYPE)(a_ChunkDesc.GetChunkZ() * cChunkDef::Width + z)) / Frequency;
+			for (int x = 0; x < cChunkDef::Width; x++)
+			{
+				NOISE_DATATYPE NoiseX = ((NOISE_DATATYPE)(a_ChunkDesc.GetChunkX() * cChunkDef::Width + x)) / Frequency;
+				NOISE_DATATYPE DistortX = m_NoiseX.CubicNoise3D(NoiseX, NoiseY, NoiseZ) * Amount;
+				NOISE_DATATYPE DistortY = m_NoiseY.CubicNoise3D(NoiseX, NoiseY, NoiseZ) * Amount;
+				NOISE_DATATYPE DistortZ = m_NoiseZ.CubicNoise3D(NoiseX, NoiseY, NoiseZ) * Amount;
+				int MembraneHeight = 96 - (int)((DistortY + m_NoiseH.CubicNoise2D(NoiseX + DistortX, NoiseZ + DistortZ)) * 30);
+				if (MembraneHeight < y)
+				{
+					a_ChunkDesc.SetBlockType(x, y, z, ReplacementBlock);
+				}
+			}  // for y
+		}  // for x
+	}  // for z
+}
+
+
+
+

src/Generating/StructGen.h

@@ -0,0 +1,165 @@
+
+// StructGen.h
+
+/* Interfaces to the various structure generators:
+	- cStructGenTrees
+	- cStructGenMarbleCaves
+	- cStructGenOres
+*/
+
+
+
+
+
+#pragma once
+
+#include "ComposableGenerator.h"
+#include "../Noise.h"
+
+
+
+
+
+class cStructGenTrees :
+	public cStructureGen
+{
+public:
+	cStructGenTrees(int a_Seed, cBiomeGen * a_BiomeGen, cTerrainHeightGen * a_HeightGen, cTerrainCompositionGen * a_CompositionGen) :
+		m_Seed(a_Seed),
+		m_Noise(a_Seed),
+		m_BiomeGen(a_BiomeGen),
+		m_HeightGen(a_HeightGen),
+		m_CompositionGen(a_CompositionGen)
+	{}
+	
+protected:
+
+	int m_Seed;
+	cNoise m_Noise;
+	cBiomeGen *              m_BiomeGen;
+	cTerrainHeightGen *      m_HeightGen;
+	cTerrainCompositionGen * m_CompositionGen;
+	
+	/** Generates and applies an image of a single tree.
+	Parts of the tree inside the chunk are applied to a_BlockX.
+	Parts of the tree outside the chunk are stored in a_OutsideX
+	*/
+	void GenerateSingleTree(
+		int a_ChunkX, int a_ChunkZ, int a_Seq,
+		cChunkDesc & a_ChunkDesc,
+		sSetBlockVector & a_OutsideLogs,
+		sSetBlockVector & a_OutsideOther
+	) ;
+	
+	/// Applies an image into chunk blockdata; all blocks outside the chunk will be appended to a_Overflow
+	void ApplyTreeImage(
+		int a_ChunkX, int a_ChunkZ,
+		cChunkDesc & a_ChunkDesc,
+		const sSetBlockVector & a_Image,
+		sSetBlockVector & a_Overflow
+	);
+
+	int GetNumTrees(
+		int a_ChunkX, int a_ChunkZ,
+		const cChunkDef::BiomeMap & a_Biomes
+	);
+	
+	// cStructureGen override:
+	virtual void GenStructures(cChunkDesc & a_ChunkDesc) override;
+} ;
+
+
+
+
+
+class cStructGenOreNests :
+	public cStructureGen
+{
+public:
+	cStructGenOreNests(int a_Seed) : m_Noise(a_Seed), m_Seed(a_Seed) {}
+	
+protected:
+	cNoise m_Noise;
+	int    m_Seed;
+	
+	// cStructureGen override:
+	virtual void GenStructures(cChunkDesc & a_ChunkDesc) override;
+	
+	void GenerateOre(int a_ChunkX, int a_ChunkZ, BLOCKTYPE a_OreType, int a_MaxHeight, int a_NumNests, int a_NestSize, cChunkDef::BlockTypes & a_BlockTypes, int a_Seq);
+} ;
+
+
+
+
+
+class cStructGenLakes :
+	public cStructureGen
+{
+public:
+	cStructGenLakes(int a_Seed, BLOCKTYPE a_Fluid, cTerrainHeightGen & a_HeiGen, int a_Probability) :
+		m_Noise(a_Seed),
+		m_Seed(a_Seed),
+		m_Fluid(a_Fluid),
+		m_HeiGen(a_HeiGen),
+		m_Probability(a_Probability)
+	{
+	}
+	
+protected:
+	cNoise              m_Noise;
+	int                 m_Seed;
+	BLOCKTYPE           m_Fluid;
+	cTerrainHeightGen & m_HeiGen;
+	int                 m_Probability;  ///< Chance, 0 .. 100, of a chunk having the lake
+	
+	// cStructureGen override:
+	virtual void GenStructures(cChunkDesc & a_ChunkDesc) override;
+	
+	/// Creates a lake image for the specified chunk into a_Lake
+	void CreateLakeImage(int a_ChunkX, int a_ChunkZ, cBlockArea & a_Lake);
+} ;
+
+
+
+
+
+
+class cStructGenDirectOverhangs :
+	public cStructureGen
+{
+public:
+	cStructGenDirectOverhangs(int a_Seed);
+
+protected:
+	cNoise    m_Noise1;
+	cNoise    m_Noise2;
+	
+	// cStructureGen override:
+	virtual void GenStructures(cChunkDesc & a_ChunkDesc) override;
+
+	bool HasWantedBiome(cChunkDesc & a_ChunkDesc) const;
+} ;
+
+
+
+
+
+class cStructGenDistortedMembraneOverhangs :
+	public cStructureGen
+{
+public:
+	cStructGenDistortedMembraneOverhangs(int a_Seed);
+
+protected:
+	cNoise m_NoiseX;
+	cNoise m_NoiseY;
+	cNoise m_NoiseZ;
+	cNoise m_NoiseH;
+	
+	// cStructureGen override:
+	virtual void GenStructures(cChunkDesc & a_ChunkDesc) override;
+} ;
+
+
+
+

src/Generating/Trees.cpp

@@ -0,0 +1,684 @@
+
+// Trees.cpp
+
+// Implements helper functions used for generating trees
+
+#include "Globals.h"
+#include "Trees.h"
+#include "../BlockID.h"
+
+
+
+
+// DEBUG:
+int gTotalLargeJungleTrees = 0;
+int gOversizeLargeJungleTrees = 0;
+
+
+
+
+
+typedef struct
+{
+	int x, z;
+} sCoords;
+
+typedef struct
+{
+	int x, z;
+	NIBBLETYPE Meta;
+} sMetaCoords;
+
+static const sCoords Corners[] =
+{
+	{-1, -1},
+	{-1, 1},
+	{1, -1},
+	{1, 1},
+} ;
+
+// BigO = a big ring of blocks, used for generating horz slices of treetops, the number indicates the radius
+
+static const sCoords BigO1[] =
+{
+	          {0, -1},
+	{-1,  0},          {1,  0},
+	          {0,  1},
+} ;
+
+static const sCoords BigO2[] =
+{
+	          {-1, -2}, {0, -2}, {1, -2},
+	{-2, -1}, {-1, -1}, {0, -1}, {1, -1}, {2, -1},
+	{-2,  0}, {-1,  0},          {1,  0}, {2,  0},
+	{-2,  1}, {-1,  1}, {0,  1}, {1,  1}, {2,  1},
+	          {-1,  2}, {0,  2}, {1,  2},
+} ;
+
+static const sCoords BigO3[] =
+{
+	          {-2, -3}, {-1, -3}, {0, -3}, {1, -3}, {2, -3},
+	{-3, -2}, {-2, -2}, {-1, -2}, {0, -2}, {1, -2}, {2, -2}, {3, -2},
+	{-3, -1}, {-2, -1}, {-1, -1}, {0, -1}, {1, -1}, {2, -1}, {3, -1},
+	{-3,  0}, {-2,  0}, {-1,  0},          {1,  0}, {2,  0}, {3,  0},
+	{-3,  1}, {-2,  1}, {-1,  1}, {0,  1}, {1,  1}, {2,  1}, {3,  1},
+	{-3,  2}, {-2,  2}, {-1,  2}, {0,  2}, {1,  2}, {2,  2}, {3,  2},
+	          {-2,  3}, {-1,  3}, {0,  3}, {1,  3}, {2,  3},
+} ;
+
+static const sCoords BigO4[] = // Part of Big Jungle tree
+{
+	                    {-2, -4}, {-1, -4}, {0, -4}, {1, -4}, {2, -4},
+	          {-3, -3}, {-2, -3}, {-1, -3}, {0, -3}, {1, -3}, {2, -3}, {3, -3},
+	{-4, -2}, {-3, -2}, {-2, -2}, {-1, -2}, {0, -2}, {1, -2}, {2, -2}, {3, -2}, {4, -2},
+	{-4, -1}, {-3, -1}, {-2, -1}, {-1, -1}, {0, -1}, {1, -1}, {2, -1}, {3, -1}, {4, -1},
+	{-4,  0}, {-3,  0}, {-2,  0}, {-1,  0},          {1,  0}, {2,  0}, {3,  0}, {4,  0},
+	{-4,  1}, {-3,  1}, {-2,  1}, {-1,  1}, {0,  1}, {1,  1}, {2,  1}, {3,  1}, {4,  1},
+	{-4,  2}, {-3,  2}, {-2,  2}, {-1,  2}, {0,  2}, {1,  2}, {2,  2}, {3,  2}, {4,  2},
+	          {-3,  3}, {-2,  3}, {-1,  3}, {0,  3}, {1,  3}, {2,  3}, {3,  3},
+	                    {-2,  4}, {-1,  4}, {0,  4}, {1,  4}, {2,  4},
+} ;
+
+
+
+
+
+typedef struct 
+{
+	const sCoords * Coords;
+	size_t          Count;
+} sCoordsArr;
+
+static const sCoordsArr BigOs[] =
+{
+	{BigO1, ARRAYCOUNT(BigO1)},
+	{BigO2, ARRAYCOUNT(BigO2)},
+	{BigO3, ARRAYCOUNT(BigO3)},
+	{BigO4, ARRAYCOUNT(BigO4)},
+} ;
+
+
+
+
+
+/// Pushes a specified layer of blocks of the same type around (x, h, z) into a_Blocks
+inline void PushCoordBlocks(int a_BlockX, int a_Height, int a_BlockZ, sSetBlockVector & a_Blocks, const sCoords * a_Coords, size_t a_NumCoords, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta)
+{
+	for (size_t i = 0; i < a_NumCoords; i++)
+	{
+		a_Blocks.push_back(sSetBlock(a_BlockX + a_Coords[i].x, a_Height, a_BlockZ + a_Coords[i].z, a_BlockType, a_Meta));
+	}
+}
+
+
+
+
+inline void PushCornerBlocks(int a_BlockX, int a_Height, int a_BlockZ, int a_Seq, cNoise & a_Noise, int a_Chance, sSetBlockVector & a_Blocks, int a_CornersDist, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta)
+{
+	for (size_t i = 0; i < ARRAYCOUNT(Corners); i++)
+	{
+		int x = a_BlockX + Corners[i].x;
+		int z = a_BlockZ + Corners[i].z;
+		if (a_Noise.IntNoise3DInt(x + 64 * a_Seq, a_Height, z + 64 * a_Seq) <= a_Chance)
+		{
+			a_Blocks.push_back(sSetBlock(x, a_Height, z, a_BlockType, a_Meta));
+		}
+	}  // for i - Corners[]
+}
+
+
+
+
+
+inline void PushSomeColumns(int a_BlockX, int a_Height, int a_BlockZ, int a_ColumnHeight, int a_Seq, cNoise & a_Noise, int a_Chance, sSetBlockVector & a_Blocks, const sMetaCoords * a_Coords, size_t a_NumCoords, BLOCKTYPE a_BlockType)
+{
+	for (size_t i = 0; i < a_NumCoords; i++)
+	{
+		int x = a_BlockX + a_Coords[i].x;
+		int z = a_BlockZ + a_Coords[i].z;
+		if (a_Noise.IntNoise3DInt(x + 64 * a_Seq, a_Height + i, z + 64 * a_Seq) <= a_Chance)
+		{
+			for (int j = 0; j < a_ColumnHeight; j++)
+			{
+				a_Blocks.push_back(sSetBlock(x, a_Height - j, z, a_BlockType, a_Coords[i].Meta));
+			}
+		}
+	}  // for i - a_Coords[]
+}
+
+
+
+
+
+void GetTreeImageByBiome(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, EMCSBiome a_Biome, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks)
+{
+	switch (a_Biome)
+	{
+		case biPlains:
+		case biExtremeHills:
+		case biExtremeHillsEdge:
+		case biForest:
+		case biMushroomIsland:
+		case biMushroomShore:
+		case biForestHills:
+		{
+			// Apple or birch trees:
+			if (a_Noise.IntNoise3DInt(a_BlockX, a_BlockY + 16 * a_Seq, a_BlockZ + 16 * a_Seq) < 0x5fffffff)
+			{
+				GetAppleTreeImage(a_BlockX, a_BlockY, a_BlockZ, a_Noise, a_Seq, a_LogBlocks, a_OtherBlocks);
+			}
+			else
+			{
+				GetBirchTreeImage(a_BlockX, a_BlockY, a_BlockZ, a_Noise, a_Seq, a_LogBlocks, a_OtherBlocks);
+			}
+			break;
+		}
+		
+		case biTaiga:
+		case biIcePlains:
+		case biIceMountains:
+		case biTaigaHills:
+		{
+			// Conifers
+			GetConiferTreeImage(a_BlockX, a_BlockY, a_BlockZ, a_Noise, a_Seq, a_LogBlocks, a_OtherBlocks);
+			break;
+		}
+		
+		case biSwampland:
+		{
+			// Swamp trees:
+			GetSwampTreeImage(a_BlockX, a_BlockY, a_BlockZ, a_Noise, a_Seq, a_LogBlocks, a_OtherBlocks);
+			break;
+		}
+		
+		case biJungle:
+		case biJungleHills:
+		{
+			// Apple bushes, large jungle trees, small jungle trees
+			if (a_Noise.IntNoise3DInt(a_BlockX, a_BlockY + 16 * a_Seq, a_BlockZ + 16 * a_Seq) < 0x6fffffff)
+			{
+				GetAppleBushImage(a_BlockX, a_BlockY, a_BlockZ, a_Noise, a_Seq, a_LogBlocks, a_OtherBlocks);
+			}
+			else 
+			{
+				GetJungleTreeImage(a_BlockX, a_BlockY, a_BlockZ, a_Noise, a_Seq, a_LogBlocks, a_OtherBlocks);
+			}
+		}
+	}
+}
+
+
+
+
+
+void GetAppleTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks)
+{
+	if (a_Noise.IntNoise3DInt(a_BlockX + 32 * a_Seq, a_BlockY + 32 * a_Seq, a_BlockZ) < 0x60000000)
+	{
+		GetSmallAppleTreeImage(a_BlockX, a_BlockY, a_BlockZ, a_Noise, a_Seq, a_LogBlocks, a_OtherBlocks);
+	}
+	else
+	{
+		GetLargeAppleTreeImage(a_BlockX, a_BlockY, a_BlockZ, a_Noise, a_Seq, a_LogBlocks, a_OtherBlocks);
+	}
+}
+
+
+
+
+
+void GetSmallAppleTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks)
+{
+	/* Small apple tree has:
+	- a top plus (no log)
+	- optional BigO1 + random corners (log)
+	- 2 layers of BigO2 + random corners (log)
+	- 1 to 3 blocks of trunk
+	*/
+	
+	int Random = a_Noise.IntNoise3DInt(a_BlockX + 64 * a_Seq, a_BlockY, a_BlockZ) >> 3;
+	
+	int Heights[] = {1, 2, 2, 3} ;
+	int Height = 1 + Heights[Random & 3];
+	Random >>= 2;
+	
+	// Pre-alloc so that we don't realloc too often later:
+	a_LogBlocks.reserve(Height + 5);
+	a_OtherBlocks.reserve(ARRAYCOUNT(BigO2) * 2 + ARRAYCOUNT(BigO1) + ARRAYCOUNT(Corners) * 3 + 3 + 5);
+	
+	// Trunk:
+	for (int i = 0; i < Height; i++)
+	{
+		a_LogBlocks.push_back(sSetBlock(a_BlockX, a_BlockY + i, a_BlockZ, E_BLOCK_LOG, E_META_LOG_APPLE));
+	}
+	int Hei = a_BlockY + Height;
+	
+	// 2 BigO2 + corners layers:
+	for (int i = 0; i < 2; i++)
+	{
+		PushCoordBlocks (a_BlockX, Hei, a_BlockZ, a_OtherBlocks, BigO2, ARRAYCOUNT(BigO2), E_BLOCK_LEAVES, E_META_LEAVES_APPLE);
+		PushCornerBlocks(a_BlockX, Hei, a_BlockZ, a_Seq, a_Noise, 0x5000000 - i * 0x10000000, a_OtherBlocks, 2, E_BLOCK_LEAVES, E_META_LEAVES_APPLE);
+		a_LogBlocks.push_back(sSetBlock(a_BlockX, Hei, a_BlockZ, E_BLOCK_LOG, E_META_LOG_APPLE));
+		Hei++;
+	}  // for i - 2*
+	
+	// Optional BigO1 + corners layer:
+	if ((Random & 1) == 0)
+	{
+		PushCoordBlocks (a_BlockX, Hei, a_BlockZ, a_OtherBlocks, BigO1, ARRAYCOUNT(BigO1), E_BLOCK_LEAVES, E_META_LEAVES_APPLE);
+		PushCornerBlocks(a_BlockX, Hei, a_BlockZ, a_Seq, a_Noise, 0x6000000, a_OtherBlocks, 1, E_BLOCK_LEAVES, E_META_LEAVES_APPLE);
+		a_LogBlocks.push_back(sSetBlock(a_BlockX, Hei, a_BlockZ, E_BLOCK_LOG, E_META_LOG_APPLE));
+		Hei++;
+	}
+	
+	// Top plus:
+	PushCoordBlocks(a_BlockX, Hei, a_BlockZ, a_OtherBlocks, BigO1, ARRAYCOUNT(BigO1), E_BLOCK_LEAVES, E_META_LEAVES_APPLE);
+	a_OtherBlocks.push_back(sSetBlock(a_BlockX, Hei, a_BlockZ, E_BLOCK_LEAVES, E_META_LEAVES_APPLE));
+}
+
+
+
+
+
+void GetLargeAppleTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks)
+{
+	// TODO
+}
+
+
+
+
+
+void GetBirchTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks)
+{
+	int Height = 5 + (a_Noise.IntNoise3DInt(a_BlockX + 64 * a_Seq, a_BlockY, a_BlockZ) % 3);
+	
+	// Prealloc, so that we don't realloc too often later:
+	a_LogBlocks.reserve(Height);
+	a_OtherBlocks.reserve(80);
+	
+	// The entire trunk, out of logs:
+	for (int i = Height - 1; i >= 0; --i)
+	{
+		a_LogBlocks.push_back(sSetBlock(a_BlockX, a_BlockY + i, a_BlockZ, E_BLOCK_LOG, E_META_LOG_BIRCH));
+	}
+	int h = a_BlockY + Height;
+	
+	// Top layer - just the Plus:
+	PushCoordBlocks(a_BlockX, h, a_BlockZ, a_OtherBlocks, BigO1, ARRAYCOUNT(BigO1), E_BLOCK_LEAVES, E_META_LEAVES_BIRCH);
+	a_OtherBlocks.push_back(sSetBlock(a_BlockX, h, a_BlockZ, E_BLOCK_LEAVES, E_META_LEAVES_BIRCH));  // There's no log at this layer
+	h--;
+	
+	// Second layer - log, Plus and maybe Corners:
+	PushCoordBlocks (a_BlockX, h, a_BlockZ, a_OtherBlocks, BigO1, ARRAYCOUNT(BigO1), E_BLOCK_LEAVES, E_META_LEAVES_BIRCH);
+	PushCornerBlocks(a_BlockX, h, a_BlockZ, a_Seq, a_Noise, 0x5fffffff, a_OtherBlocks, 1, E_BLOCK_LEAVES, E_META_LEAVES_BIRCH);
+	h--;
+	
+	// Third and fourth layers - BigO2 and maybe 2*Corners:
+	for (int Row = 0; Row < 2; Row++)
+	{
+		PushCoordBlocks (a_BlockX, h, a_BlockZ, a_OtherBlocks, BigO2, ARRAYCOUNT(BigO2), E_BLOCK_LEAVES, E_META_LEAVES_BIRCH);
+		PushCornerBlocks(a_BlockX, h, a_BlockZ, a_Seq, a_Noise, 0x3fffffff + Row * 0x10000000, a_OtherBlocks, 2, E_BLOCK_LEAVES, E_META_LEAVES_BIRCH);
+		h--;
+	}  // for Row - 2*
+}
+
+
+
+
+
+void GetConiferTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks)
+{
+	// Half chance for a spruce, half for a pine:
+	if (a_Noise.IntNoise3DInt(a_BlockX + 64 * a_Seq, a_BlockY, a_BlockZ + 32 * a_Seq) < 0x40000000)
+	{
+		GetSpruceTreeImage(a_BlockX, a_BlockY, a_BlockZ, a_Noise, a_Seq, a_LogBlocks, a_OtherBlocks);
+	}
+	else
+	{
+		GetPineTreeImage(a_BlockX, a_BlockY, a_BlockZ, a_Noise, a_Seq, a_LogBlocks, a_OtherBlocks);
+	}
+}
+
+
+
+
+
+void GetSpruceTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks)
+{
+	// Spruces have a top section with layer sizes of (0, 1, 0) or only (1, 0),
+	// then 1 - 3 sections of ascending sizes (1, 2) [most often], (1, 3) or (1, 2, 3)
+	// and an optional bottom section of size 1, followed by 1 - 3 clear trunk blocks
+	
+	// We'll use bits from this number as partial random numbers; but the noise function has mod8 irregularities
+	// (each of the mod8 remainders has a very different chance of occurrence) - that's why we divide by 8
+	int MyRandom = a_Noise.IntNoise3DInt(a_BlockX + 32 * a_Seq, a_BlockY + 32 * a_Seq, a_BlockZ) / 8;
+	
+	static const int  sHeights[] = {1, 2, 2, 3};
+	int Height = sHeights[MyRandom & 3];
+	MyRandom >>= 2;
+
+	// Prealloc, so that we don't realloc too often later:
+	a_LogBlocks.reserve(Height);
+	a_OtherBlocks.reserve(180);
+	
+	// Clear trunk blocks:
+	for (int i = 0; i < Height; i++)
+	{
+		a_LogBlocks.push_back(sSetBlock(a_BlockX, a_BlockY + i, a_BlockZ, E_BLOCK_LOG, E_META_LOG_CONIFER));
+	}
+	Height += a_BlockY;
+	
+	// Optional size-1 bottom leaves layer:
+	if ((MyRandom & 1) == 0)
+	{
+		PushCoordBlocks(a_BlockX, Height, a_BlockZ, a_OtherBlocks, BigO1, ARRAYCOUNT(BigO1), E_BLOCK_LEAVES, E_META_LEAVES_CONIFER);
+		a_OtherBlocks.push_back(sSetBlock(a_BlockX, Height, a_BlockZ, E_BLOCK_LOG, E_META_LOG_CONIFER));
+		Height++;
+	}
+	MyRandom >>= 1;
+	
+	// 1 to 3 sections of leaves layers:
+	static const int sNumSections[] = {1, 2, 2, 3};
+	int NumSections = sNumSections[MyRandom & 3];
+	MyRandom >>= 2;
+	for (int i = 0; i < NumSections; i++)
+	{
+		switch (MyRandom & 3)  // SectionType; (1, 2) twice as often as the other two
+		{
+			case 0:
+			case 1:
+			{
+				PushCoordBlocks(a_BlockX, Height,     a_BlockZ, a_OtherBlocks, BigO2, ARRAYCOUNT(BigO2), E_BLOCK_LEAVES, E_META_LEAVES_CONIFER);
+				PushCoordBlocks(a_BlockX, Height + 1, a_BlockZ, a_OtherBlocks, BigO1, ARRAYCOUNT(BigO1), E_BLOCK_LEAVES, E_META_LEAVES_CONIFER);
+				a_LogBlocks.push_back(sSetBlock(a_BlockX, Height,     a_BlockZ, E_BLOCK_LOG, E_META_LOG_CONIFER));
+				a_LogBlocks.push_back(sSetBlock(a_BlockX, Height + 1, a_BlockZ, E_BLOCK_LOG, E_META_LOG_CONIFER));
+				Height += 2;
+				break;
+			}
+			case 2:
+			{
+				PushCoordBlocks(a_BlockX, Height,     a_BlockZ, a_OtherBlocks, BigO3, ARRAYCOUNT(BigO3), E_BLOCK_LEAVES, E_META_LEAVES_CONIFER);
+				PushCoordBlocks(a_BlockX, Height + 1, a_BlockZ, a_OtherBlocks, BigO1, ARRAYCOUNT(BigO1), E_BLOCK_LEAVES, E_META_LEAVES_CONIFER);
+				a_LogBlocks.push_back(sSetBlock(a_BlockX, Height,     a_BlockZ, E_BLOCK_LOG, E_META_LOG_CONIFER));
+				a_LogBlocks.push_back(sSetBlock(a_BlockX, Height + 1, a_BlockZ, E_BLOCK_LOG, E_META_LOG_CONIFER));
+				Height += 2;
+				break;
+			}
+			case 3:
+			{
+				PushCoordBlocks(a_BlockX, Height,     a_BlockZ, a_OtherBlocks, BigO3, ARRAYCOUNT(BigO3), E_BLOCK_LEAVES, E_META_LEAVES_CONIFER);
+				PushCoordBlocks(a_BlockX, Height + 1, a_BlockZ, a_OtherBlocks, BigO2, ARRAYCOUNT(BigO2), E_BLOCK_LEAVES, E_META_LEAVES_CONIFER);
+				PushCoordBlocks(a_BlockX, Height + 2, a_BlockZ, a_OtherBlocks, BigO1, ARRAYCOUNT(BigO1), E_BLOCK_LEAVES, E_META_LEAVES_CONIFER);
+				a_LogBlocks.push_back(sSetBlock(a_BlockX, Height,     a_BlockZ, E_BLOCK_LOG, E_META_LOG_CONIFER));
+				a_LogBlocks.push_back(sSetBlock(a_BlockX, Height + 1, a_BlockZ, E_BLOCK_LOG, E_META_LOG_CONIFER));
+				a_LogBlocks.push_back(sSetBlock(a_BlockX, Height + 2, a_BlockZ, E_BLOCK_LOG, E_META_LOG_CONIFER));
+				Height += 3;
+				break;
+			}
+		}  // switch (SectionType)
+		MyRandom >>= 2;
+	}  // for i - Sections
+	
+	if ((MyRandom & 1) == 0)
+	{
+		// (0, 1, 0) top:
+		a_LogBlocks.push_back  (sSetBlock(a_BlockX, Height,     a_BlockZ, E_BLOCK_LOG, E_META_LOG_CONIFER));
+		PushCoordBlocks                  (a_BlockX, Height + 1, a_BlockZ, a_OtherBlocks, BigO1, ARRAYCOUNT(BigO1), E_BLOCK_LEAVES, E_META_LEAVES_CONIFER);
+		a_OtherBlocks.push_back(sSetBlock(a_BlockX, Height + 1, a_BlockZ, E_BLOCK_LEAVES, E_META_LEAVES_CONIFER));
+		a_OtherBlocks.push_back(sSetBlock(a_BlockX, Height + 2, a_BlockZ, E_BLOCK_LEAVES, E_META_LEAVES_CONIFER));
+	}
+	else
+	{
+		// (1, 0) top:
+		a_OtherBlocks.push_back(sSetBlock(a_BlockX, Height,     a_BlockZ, E_BLOCK_LEAVES, E_META_LEAVES_CONIFER));
+		PushCoordBlocks                  (a_BlockX, Height + 1, a_BlockZ, a_OtherBlocks, BigO1, ARRAYCOUNT(BigO1), E_BLOCK_LEAVES, E_META_LEAVES_CONIFER);
+		a_OtherBlocks.push_back(sSetBlock(a_BlockX, Height + 1, a_BlockZ, E_BLOCK_LEAVES, E_META_LEAVES_CONIFER));
+	}
+}
+
+
+
+
+
+void GetPineTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks)
+{
+	// Tall, little leaves on top. The top leaves are arranged in a shape of two cones joined by their bases.
+	// There can be one or two layers representing the cone bases (SameSizeMax)
+	
+	int MyRandom = a_Noise.IntNoise3DInt(a_BlockX + 32 * a_Seq, a_BlockY, a_BlockZ + 32 * a_Seq) / 8;
+	int TrunkHeight = 8 + (MyRandom % 3);
+	int SameSizeMax = ((MyRandom & 8) == 0) ? 1 : 0;
+	MyRandom >>= 3;
+	int NumLeavesLayers = 2 + (MyRandom % 3);  // Number of layers that have leaves in them
+	if (NumLeavesLayers == 2)
+	{
+		SameSizeMax = 0;
+	}
+	
+	// Pre-allocate the vector:
+	a_LogBlocks.reserve(TrunkHeight);
+	a_OtherBlocks.reserve(NumLeavesLayers * 25);
+
+	// The entire trunk, out of logs:
+	for (int i = TrunkHeight; i >= 0; --i)
+	{
+		a_LogBlocks.push_back(sSetBlock(a_BlockX, a_BlockY + i, a_BlockZ, E_BLOCK_LOG, E_META_LOG_CONIFER));
+	}
+	int h = a_BlockY + TrunkHeight + 2;
+
+	// Top layer - just a single leaves block:	
+	a_OtherBlocks.push_back(sSetBlock(a_BlockX, h, a_BlockZ, E_BLOCK_LEAVES, E_META_LEAVES_CONIFER));
+	h--;
+
+	// One more layer is above the trunk, push the central leaves:	
+	a_OtherBlocks.push_back(sSetBlock(a_BlockX, h, a_BlockZ, E_BLOCK_LEAVES, E_META_LEAVES_CONIFER));
+
+	// Layers expanding in size, then collapsing again:
+	// LOGD("Generating %d layers of pine leaves, SameSizeMax = %d", NumLeavesLayers, SameSizeMax);
+	for (int i = 0; i < NumLeavesLayers; ++i)
+	{
+		int LayerSize = std::min(i, NumLeavesLayers - i + SameSizeMax - 1);
+		// LOGD("LayerSize %d: %d", i, LayerSize);
+		if (LayerSize < 0)
+		{
+			break;
+		}
+		ASSERT(LayerSize < ARRAYCOUNT(BigOs));
+		PushCoordBlocks(a_BlockX, h, a_BlockZ, a_OtherBlocks, BigOs[LayerSize].Coords, BigOs[LayerSize].Count, E_BLOCK_LEAVES, E_META_LEAVES_CONIFER);
+		h--;
+	}
+}
+
+
+
+
+
+void GetSwampTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks)
+{
+	// Vines are around the BigO3, but not in the corners; need proper meta for direction
+	static const sMetaCoords Vines[] =
+	{
+		{-2, -4, 1}, {-1, -4, 1}, {0, -4, 1}, {1, -4, 1}, {2, -4, 1},  // North face
+		{-2,  4, 4}, {-1,  4, 4}, {0,  4, 4}, {1,  4, 4}, {2,  4, 4},  // South face
+		{4,  -2, 2}, {4,  -1, 2}, {4,  0, 2}, {4,  1, 2}, {4,  2, 2},  // East face
+		{-4, -2, 8}, {-4, -1, 8}, {-4, 0, 8}, {-4, 1, 8}, {-4, 2, 8},  // West face
+	} ;
+
+	int Height = 3 + (a_Noise.IntNoise3DInt(a_BlockX + 32 * a_Seq, a_BlockY, a_BlockZ + 32 * a_Seq) / 8) % 3;
+	
+	a_LogBlocks.reserve(Height);
+	a_OtherBlocks.reserve(2 * ARRAYCOUNT(BigO2) + 2 * ARRAYCOUNT(BigO3) + Height * ARRAYCOUNT(Vines) + 20);
+	
+	for (int i = 0; i < Height; i++)
+	{
+		a_LogBlocks.push_back(sSetBlock(a_BlockX, a_BlockY + i, a_BlockZ, E_BLOCK_LOG, E_META_LOG_APPLE));
+	}
+	int hei = a_BlockY + Height - 2;
+	
+	// Put vines around the lowermost leaves layer:
+	PushSomeColumns(a_BlockX, hei, a_BlockZ, Height, a_Seq, a_Noise, 0x3fffffff, a_OtherBlocks, Vines, ARRAYCOUNT(Vines), E_BLOCK_VINES);
+	
+	// The lower two leaves layers are BigO3 with log in the middle and possibly corners:
+	for (int i = 0; i < 2; i++)
+	{
+		PushCoordBlocks(a_BlockX, hei, a_BlockZ, a_OtherBlocks, BigO3, ARRAYCOUNT(BigO3), E_BLOCK_LEAVES, E_META_LEAVES_APPLE);
+		PushCornerBlocks(a_BlockX, hei, a_BlockZ, a_Seq, a_Noise, 0x5fffffff, a_OtherBlocks, 3, E_BLOCK_LEAVES, E_META_LEAVES_APPLE);
+		hei++;
+	}  // for i - 2*
+
+	// The upper two leaves layers are BigO2 with leaves in the middle and possibly corners:
+	for (int i = 0; i < 2; i++)
+	{
+		PushCoordBlocks(a_BlockX, hei, a_BlockZ, a_OtherBlocks, BigO2, ARRAYCOUNT(BigO2), E_BLOCK_LEAVES, E_META_LEAVES_APPLE);
+		PushCornerBlocks(a_BlockX, hei, a_BlockZ, a_Seq, a_Noise, 0x5fffffff, a_OtherBlocks, 3, E_BLOCK_LEAVES, E_META_LEAVES_APPLE);
+		a_OtherBlocks.push_back(sSetBlock(a_BlockX, hei, a_BlockZ, E_BLOCK_LEAVES, E_META_LEAVES_APPLE));
+		hei++;
+	}  // for i - 2*
+}
+
+
+
+
+
+void GetAppleBushImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks)
+{
+	a_OtherBlocks.reserve(3 + ARRAYCOUNT(BigO2) + ARRAYCOUNT(BigO1));
+	
+	int hei = a_BlockY;
+	a_LogBlocks.push_back(sSetBlock(a_BlockX, hei, a_BlockZ, E_BLOCK_LOG, E_META_LOG_JUNGLE));
+	PushCoordBlocks(a_BlockX, hei, a_BlockZ, a_OtherBlocks, BigO2, ARRAYCOUNT(BigO2), E_BLOCK_LEAVES, E_META_LEAVES_APPLE);
+	hei++;
+	
+	a_OtherBlocks.push_back(sSetBlock(a_BlockX, hei, a_BlockZ, E_BLOCK_LEAVES, E_META_LEAVES_APPLE));
+	PushCoordBlocks(a_BlockX, hei, a_BlockZ, a_OtherBlocks, BigO1, ARRAYCOUNT(BigO1), E_BLOCK_LEAVES, E_META_LEAVES_APPLE);
+	hei++;
+	
+	a_OtherBlocks.push_back(sSetBlock(a_BlockX, hei, a_BlockZ, E_BLOCK_LEAVES, E_META_LEAVES_APPLE));
+}
+
+
+
+
+
+void GetJungleTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks)
+{
+	if (a_Noise.IntNoise3DInt(a_BlockX + 32 * a_Seq, a_BlockY + 32 * a_Seq, a_BlockZ) < 0x60000000)
+	{
+		GetSmallJungleTreeImage(a_BlockX, a_BlockY, a_BlockZ, a_Noise, a_Seq, a_LogBlocks, a_OtherBlocks);
+	}
+	else
+	{
+		GetLargeJungleTreeImage(a_BlockX, a_BlockY, a_BlockZ, a_Noise, a_Seq, a_LogBlocks, a_OtherBlocks);
+	}
+}
+
+
+
+
+
+void GetLargeJungleTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks)
+{
+	// TODO: Generate proper jungle trees with branches
+
+	// Vines are around the BigO4, but not in the corners; need proper meta for direction
+	static const sMetaCoords Vines[] =
+	{
+		{-2, -5, 1}, {-1, -5, 1}, {0, -5, 1}, {1, -5, 1}, {2, -5, 1},  // North face
+		{-2,  5, 4}, {-1,  5, 4}, {0,  5, 4}, {1,  5, 4}, {2,  5, 4},  // South face
+		{5,  -2, 2}, {5,  -1, 2}, {5,  0, 2}, {5,  1, 2}, {5,  2, 2},  // East face
+		{-5, -2, 8}, {-5, -1, 8}, {-5, 0, 8}, {-5, 1, 8}, {-5, 2, 8},  // West face
+		// TODO: vines around the trunk, proper metas and height
+	} ;
+	
+	int Height = 24 + (a_Noise.IntNoise3DInt(a_BlockX + 32 * a_Seq, a_BlockY, a_BlockZ + 32 * a_Seq) / 11) % 24;
+	
+	a_LogBlocks.reserve(Height * 4);
+	a_OtherBlocks.reserve(2 * ARRAYCOUNT(BigO4) + ARRAYCOUNT(BigO3) + Height * ARRAYCOUNT(Vines) + 50);
+	
+	for (int i = 0; i < Height; i++)
+	{
+		a_LogBlocks.push_back(sSetBlock(a_BlockX,     a_BlockY + i, a_BlockZ,     E_BLOCK_LOG, E_META_LOG_JUNGLE));
+		a_LogBlocks.push_back(sSetBlock(a_BlockX + 1, a_BlockY + i, a_BlockZ,     E_BLOCK_LOG, E_META_LOG_JUNGLE));
+		a_LogBlocks.push_back(sSetBlock(a_BlockX,     a_BlockY + i, a_BlockZ + 1, E_BLOCK_LOG, E_META_LOG_JUNGLE));
+		a_LogBlocks.push_back(sSetBlock(a_BlockX + 1, a_BlockY + i, a_BlockZ + 1, E_BLOCK_LOG, E_META_LOG_JUNGLE));
+	}
+	int hei = a_BlockY + Height - 2;
+	
+	// Put vines around the lowermost leaves layer:
+	PushSomeColumns(a_BlockX, hei, a_BlockZ, Height, a_Seq, a_Noise, 0x3fffffff, a_OtherBlocks, Vines, ARRAYCOUNT(Vines), E_BLOCK_VINES);
+	
+	// The lower two leaves layers are BigO4 with log in the middle and possibly corners:
+	for (int i = 0; i < 2; i++)
+	{
+		PushCoordBlocks(a_BlockX, hei, a_BlockZ, a_OtherBlocks, BigO4, ARRAYCOUNT(BigO4), E_BLOCK_LEAVES, E_META_LEAVES_JUNGLE);
+		PushCornerBlocks(a_BlockX, hei, a_BlockZ, a_Seq, a_Noise, 0x5fffffff, a_OtherBlocks, 3, E_BLOCK_LEAVES, E_META_LEAVES_JUNGLE);
+		hei++;
+	}  // for i - 2*
+
+	// The top leaves layer is a BigO3 with leaves in the middle and possibly corners:
+	PushCoordBlocks(a_BlockX, hei, a_BlockZ, a_OtherBlocks, BigO3, ARRAYCOUNT(BigO3), E_BLOCK_LEAVES, E_META_LEAVES_JUNGLE);
+	PushCornerBlocks(a_BlockX, hei, a_BlockZ, a_Seq, a_Noise, 0x5fffffff, a_OtherBlocks, 3, E_BLOCK_LEAVES, E_META_LEAVES_JUNGLE);
+	a_OtherBlocks.push_back(sSetBlock(a_BlockX, hei, a_BlockZ, E_BLOCK_LEAVES, E_META_LEAVES_JUNGLE));
+}
+
+
+
+
+
+void GetSmallJungleTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks)
+{
+	// Vines are around the BigO3, but not in the corners; need proper meta for direction
+	static const sMetaCoords Vines[] =
+	{
+		{-2, -4, 1}, {-1, -4, 1}, {0, -4, 1}, {1, -4, 1}, {2, -4, 1},  // North face
+		{-2,  4, 4}, {-1,  4, 4}, {0,  4, 4}, {1,  4, 4}, {2,  4, 4},  // South face
+		{4,  -2, 2}, {4,  -1, 2}, {4,  0, 2}, {4,  1, 2}, {4,  2, 2},  // East face
+		{-4, -2, 8}, {-4, -1, 8}, {-4, 0, 8}, {-4, 1, 8},              // West face
+		// TODO: proper metas and height: {0,  1, 1},  {0, -1, 4},  {-1, 0, 2}, {1,  1, 8},  // Around the tunk
+	} ;
+
+	int Height = 7 + (a_Noise.IntNoise3DInt(a_BlockX + 5 * a_Seq, a_BlockY, a_BlockZ + 5 * a_Seq) / 5) % 3;
+	
+	a_LogBlocks.reserve(Height);
+	a_OtherBlocks.reserve(
+		2 * ARRAYCOUNT(BigO3) +      // O3 layer, 2x
+		2 * ARRAYCOUNT(BigO2) +      // O2 layer, 2x
+		ARRAYCOUNT(BigO1) + 1 +      // Plus on the top
+		Height * ARRAYCOUNT(Vines) + // Vines
+		50  // some safety
+	);
+	
+	for (int i = 0; i < Height; i++)
+	{
+		a_LogBlocks.push_back(sSetBlock(a_BlockX, a_BlockY + i, a_BlockZ, E_BLOCK_LOG, E_META_LOG_JUNGLE));
+	}
+	int hei = a_BlockY + Height - 3;
+	
+	// Put vines around the lowermost leaves layer:
+	PushSomeColumns(a_BlockX, hei, a_BlockZ, Height, a_Seq, a_Noise, 0x3fffffff, a_OtherBlocks, Vines, ARRAYCOUNT(Vines), E_BLOCK_VINES);
+	
+	// The lower two leaves layers are BigO3 with log in the middle and possibly corners:
+	for (int i = 0; i < 2; i++)
+	{
+		PushCoordBlocks(a_BlockX, hei, a_BlockZ, a_OtherBlocks, BigO3, ARRAYCOUNT(BigO3), E_BLOCK_LEAVES, E_META_LEAVES_JUNGLE);
+		PushCornerBlocks(a_BlockX, hei, a_BlockZ, a_Seq, a_Noise, 0x5fffffff, a_OtherBlocks, 3, E_BLOCK_LEAVES, E_META_LEAVES_JUNGLE);
+		hei++;
+	}  // for i - 2*
+
+	// Two layers of BigO2 leaves, possibly with corners:
+	for (int i = 0; i < 1; i++)
+	{
+		PushCoordBlocks(a_BlockX, hei, a_BlockZ, a_OtherBlocks, BigO2, ARRAYCOUNT(BigO2), E_BLOCK_LEAVES, E_META_LEAVES_JUNGLE);
+		PushCornerBlocks(a_BlockX, hei, a_BlockZ, a_Seq, a_Noise, 0x5fffffff, a_OtherBlocks, 2, E_BLOCK_LEAVES, E_META_LEAVES_JUNGLE);
+		hei++;
+	}  // for i - 2*
+	
+	// Top plus, all leaves:
+	PushCoordBlocks(a_BlockX, hei, a_BlockZ, a_OtherBlocks, BigO1, ARRAYCOUNT(BigO1), E_BLOCK_LEAVES, E_META_LEAVES_JUNGLE);
+	a_OtherBlocks.push_back(sSetBlock(a_BlockX, hei, a_BlockZ, E_BLOCK_LEAVES, E_META_LEAVES_JUNGLE));
+}
+
+
+
+

src/Generating/Trees.h

@@ -0,0 +1,93 @@
+
+// Trees.h
+
+// Interfaces to helper functions used for generating trees
+
+/*
+Note that all of these functions must generate the same tree image for the same input (x, y, z, seq)
+	- cStructGenTrees depends on this
+To generate a random image for the (x, y, z) coords, pass an arbitrary value as (seq).
+Each function returns two arrays of blocks, "logs" and "other". The point is that logs are of higher priority,
+logs can overwrite others(leaves), but others shouldn't overwrite logs. This is an optimization for the generator.
+*/
+
+
+
+
+
+#pragma once
+
+#include "../ChunkDef.h"
+#include "../Noise.h"
+
+
+
+
+
+// Blocks that don't block tree growth:
+#define CASE_TREE_ALLOWED_BLOCKS \
+	case E_BLOCK_AIR: \
+	case E_BLOCK_LEAVES: \
+	case E_BLOCK_SNOW: \
+	case E_BLOCK_TALL_GRASS: \
+	case E_BLOCK_DEAD_BUSH: \
+	case E_BLOCK_SAPLING: \
+	case E_BLOCK_VINES
+
+// Blocks that a tree may overwrite when growing:
+#define CASE_TREE_OVERWRITTEN_BLOCKS \
+	case E_BLOCK_AIR: \
+	/* case E_BLOCK_LEAVES: LEAVES are a special case, they can be overwritten only by log. Handled in cChunkMap::ReplaceTreeBlocks(). */ \
+	case E_BLOCK_SNOW: \
+	case E_BLOCK_TALL_GRASS: \
+	case E_BLOCK_DEAD_BUSH: \
+	case E_BLOCK_SAPLING: \
+	case E_BLOCK_VINES
+
+
+
+
+
+/// Generates an image of a tree at the specified coords (lowest trunk block) in the specified biome
+void GetTreeImageByBiome(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, EMCSBiome a_Biome, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks);
+
+/// Generates an image of a random apple tree
+void GetAppleTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks);
+
+/// Generates an image of a small (nonbranching) apple tree
+void GetSmallAppleTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks);
+
+/// Generates an image of a large (branching) apple tree
+void GetLargeAppleTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks);
+
+/// Generates an image of a random birch tree
+void GetBirchTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks);
+
+/// Generates an image of a random conifer tree
+void GetConiferTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks);
+
+/// Generates an image of a random spruce (short conifer, two layers of leaves)
+void GetSpruceTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks);
+
+/// Generates an image of a random pine (tall conifer, little leaves at top)
+void GetPineTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks);
+
+/// Generates an image of a random swampland tree
+void GetSwampTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks);
+
+/// Generates an image of a random apple bush (for jungles)
+void GetAppleBushImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks);
+
+/// Generates an image of a random jungle tree
+void GetJungleTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks);
+
+/// Generates an image of a large jungle tree (2x2 trunk)
+void GetLargeJungleTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks);
+
+/// Generates an image of a small jungle tree (1x1 trunk)
+void GetSmallJungleTreeImage(int a_BlockX, int a_BlockY, int a_BlockZ, cNoise & a_Noise, int a_Seq, sSetBlockVector & a_LogBlocks, sSetBlockVector & a_OtherBlocks);
+
+
+
+
+