2 files changed, 1047 insertions, 0 deletions

diff --git a/src/Generating/BioGen.cpp b/src/Generating/BioGen.cpp
index 203faff56..c9405040f 100644
--- a/src/Generating/BioGen.cpp
+++ b/src/Generating/BioGen.cpp
@@ -5,6 +5,7 @@
 
 #include "Globals.h"
 #include "BioGen.h"
+#include "IntGen.h"
 #include "../IniFile.h"
 #include "../LinearUpscale.h"
 
@@ -917,6 +918,94 @@ void cBioGenTwoLevel::InitializeBiomeGen(cIniFile & a_IniFile)
 
 
 ////////////////////////////////////////////////////////////////////////////////
+// cBioGenGrown:
+
+class cBioGenGrown:
+	public cBiomeGen
+{
+public:
+	cBioGenGrown(int a_Seed)
+	{
+		auto FinalRivers =
+			std::make_shared<cIntGenSmooth<8>>   (a_Seed + 1,
+			std::make_shared<cIntGenRiver <10>>  (a_Seed + 2,
+			std::make_shared<cIntGenZoom  <12>>  (a_Seed + 3,
+			std::make_shared<cIntGenSmooth<8>>   (a_Seed + 4,
+			std::make_shared<cIntGenZoom  <10>>  (a_Seed + 5,
+			std::make_shared<cIntGenZoom  <7>>   (a_Seed + 6,
+			std::make_shared<cIntGenZoom  <5>>   (a_Seed + 7,
+			std::make_shared<cIntGenZoom  <4>>   (a_Seed + 8,
+			std::make_shared<cIntGenZoom  <4>>   (a_Seed + 9,
+			std::make_shared<cIntGenZoom  <4>>   (a_Seed + 10,
+			std::make_shared<cIntGenZoom  <4>>   (a_Seed + 11,
+			std::make_shared<cIntGenChoice<2, 4>>(a_Seed + 12
+		))))))))))));
+
+		auto FinalBiomes =
+			std::make_shared<cIntGenSmooth         <8>> (a_Seed + 1008,
+			std::make_shared<cIntGenZoom           <10>>(a_Seed + 15,
+			std::make_shared<cIntGenSmooth         <7>> (a_Seed + 1000,
+			std::make_shared<cIntGenZoom           <9>> (a_Seed + 16,
+			std::make_shared<cIntGenSmooth         <6>> (a_Seed + 1001,
+			std::make_shared<cIntGenZoom           <8>> (a_Seed,
+			std::make_shared<cIntGenSmooth         <6>> (a_Seed + 1002,
+			std::make_shared<cIntGenZoom           <8>> (a_Seed + 1,
+			std::make_shared<cIntGenBeaches        <6>> (
+			std::make_shared<cIntGenSmooth         <8>> (a_Seed + 1002,
+			std::make_shared<cIntGenZoom           <10>>(a_Seed + 2,
+			std::make_shared<cIntGenZoom           <7>> (a_Seed + 3,
+			std::make_shared<cIntGenAddIslands     <5>> (a_Seed + 2004, 10,
+			std::make_shared<cIntGenZoom           <5>> (a_Seed + 4,
+			std::make_shared<cIntGenAddToOcean     <4>> (a_Seed + 9, 50, biMushroomIsland,
+			std::make_shared<cIntGenZoom           <6>> (a_Seed + 8,
+			std::make_shared<cIntGenAddToOcean     <5>> (a_Seed + 10, 500, biDeepOcean,
+			std::make_shared<cIntGenBiomes         <7>> (a_Seed + 3000,
+			std::make_shared<cIntGenZoom           <7>> (a_Seed + 5,
+			std::make_shared<cIntGenBiomeGroupEdges<5>> (
+			std::make_shared<cIntGenSmooth         <7>> (a_Seed + 1003,
+			std::make_shared<cIntGenZoom           <9>> (a_Seed + 7,
+			std::make_shared<cIntGenReplaceRandomly<6>> (bgJungle, bgTemperate, 50, a_Seed + 100,
+			std::make_shared<cIntGenReplaceRandomly<6>> (bgIce,    bgTemperate, 50, a_Seed + 101,
+			std::make_shared<cIntGenAddIslands     <6>> (a_Seed + 2000, 70,
+			std::make_shared<cIntGenSmooth         <6>> (a_Seed + 1004,
+			std::make_shared<cIntGenZoom           <8>> (a_Seed + 10,
+			std::make_shared<cIntGenAddIslands     <6>> (a_Seed + 2003, 50,
+			std::make_shared<cIntGenZoom           <6>> (a_Seed + 11,
+			std::make_shared<cIntLandOcean         <5>> (a_Seed + 100, 65
+		))))))))))))))))))))))))))))));
+
+		m_Gen =
+			std::make_shared<cIntGenSmooth   <16>>(a_Seed,
+			std::make_shared<cIntGenZoom     <18>>(a_Seed,
+			std::make_shared<cIntGenSmooth   <11>>(a_Seed,
+			std::make_shared<cIntGenZoom     <13>>(a_Seed,
+			std::make_shared<cIntGenMixRivers<8>> (
+			FinalBiomes, FinalRivers
+		)))));
+	}
+
+	virtual void GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_Biomes) override
+	{
+		cIntGen<16, 16>::Values vals;
+		m_Gen->GetInts(a_ChunkX * cChunkDef::Width, a_ChunkZ * cChunkDef::Width, vals);
+		for (int z = 0; z < cChunkDef::Width; z++)
+		{
+			for (int x = 0; x < cChunkDef::Width; x++)
+			{
+				cChunkDef::SetBiome(a_Biomes, x, z, (EMCSBiome)vals[x + cChunkDef::Width * z]);
+			}
+		}
+	}
+
+protected:
+	cIntGenPtr<16, 16> m_Gen;
+};
+
+
+
+
+
+////////////////////////////////////////////////////////////////////////////////
 // cBiomeGen:
 
 cBiomeGenPtr cBiomeGen::CreateBiomeGen(cIniFile & a_IniFile, int a_Seed, bool & a_CacheOffByDefault)
@@ -952,6 +1041,10 @@ cBiomeGenPtr cBiomeGen::CreateBiomeGen(cIniFile & a_IniFile, int a_Seed, bool &
 	{
 		res = new cBioGenTwoLevel(a_Seed);
 	}
+	else if (NoCaseCompare(BiomeGenName, "grown") == 0)
+	{
+		res = new cBioGenGrown(a_Seed);
+	}
 	else
 	{
 		if (NoCaseCompare(BiomeGenName, "multistepmap") != 0)
diff --git a/src/Generating/IntGen.h b/src/Generating/IntGen.h
new file mode 100644
index 000000000..ae940232f
--- /dev/null
+++ b/src/Generating/IntGen.h
@@ -0,0 +1,954 @@
+
+// IntGen.h
+
+// Declares the cIntGen class and descendants for generating and filtering various 2D arrays of ints
+
+/*
+The integers generated may be interpreted in several ways:
+- land/see designators
+	- 0 = ocean
+	- >0 = land
+- biome group designators
+	- 0 = ocean
+	- 1 = desert biomes
+	- 2 = temperate biomes
+	- 3 = mountains (hills and forests)
+	- 4 = jungle
+	- 5 = ice biomes
+- biome IDs
+The interpretation depends on the generator used and on the position in the chain.
+
+The generators can be chained together - one produces data that another one consumes.
+Some of such chain connections require changing the data dimensions between the two, which is handled automatically
+by using templates.
+*/
+
+
+
+
+
+#pragma once
+
+#include "../BiomeDef.h"
+
+
+
+
+
+/** Constants representing the biome group designators. */
+const int bgOcean     = 0;
+const int bgDesert    = 1;
+const int bgTemperate = 2;
+const int bgMountains = 3;
+const int bgJungle    = 4;
+const int bgIce       = 5;
+const int bgMax       = 5;  // Maximum biome group value
+
+
+
+
+
+/** Interface that all the generator classes provide. */
+template <int SizeX, int SizeZ = SizeX>
+class cIntGen
+{
+public:
+	/** Holds the array of values generated by this class (descendant). */
+	typedef int Values[SizeX * SizeZ];
+
+	/** Generates the array of templated size into a_Values, based on given min coords. */
+	virtual void GetInts(int a_MinX, int a_MinZ, Values & a_Values) = 0;
+};
+
+template <int SizeX, int SizeZ = SizeX>
+using cIntGenPtr = std::shared_ptr<cIntGen<SizeX, SizeZ>>;
+
+
+
+
+
+
+/** Provides additional cNoise member and its helper functions. */
+template <int SizeX, int SizeZ = SizeX>
+class cIntGenWithNoise :
+	public cIntGen<SizeX, SizeZ>
+{
+	typedef cIntGen<SizeX, SizeZ> super;
+
+public:
+	cIntGenWithNoise(int a_Seed) :
+		m_Noise(a_Seed)
+	{
+	}
+
+protected:
+	cNoise m_Noise;
+
+	/** Chooses one of a_Val1 or a_Val2, based on m_Noise and the coordinates for querying the noise. */
+	int ChooseRandomOne(int a_RndX, int a_RndZ, int a_Val1, int a_Val2)
+	{
+		int rnd = m_Noise.IntNoise2DInt(a_RndX, a_RndZ) / 7;
+		return ((rnd & 1) == 0) ? a_Val1 : a_Val2;
+	}
+
+	/** Chooses one of a_ValN, based on m_Noise and the coordinates for querying the noise. */
+	int ChooseRandomOne(int a_RndX, int a_RndZ, int a_Val1, int a_Val2, int a_Val3, int a_Val4)
+	{
+		int rnd = m_Noise.IntNoise2DInt(a_RndX, a_RndZ) / 7;
+		switch (rnd % 4)
+		{
+			case 0:  return a_Val1;
+			case 1:  return a_Val2;
+			case 2:  return a_Val3;
+			default: return a_Val4;
+		}
+	}
+};
+
+
+
+
+
+
+/** Generates a 2D array of random integers in the specified range [0 .. Range). */
+template <int Range, int SizeX, int SizeZ = SizeX>
+class cIntGenChoice :
+	public cIntGenWithNoise<SizeX, SizeZ>
+{
+	typedef cIntGenWithNoise<SizeX, SizeZ> super;
+
+public:
+	cIntGenChoice(int a_Seed) :
+		super(a_Seed)
+	{
+	}
+
+
+	virtual void GetInts(int a_MinX, int a_MinZ, Values & a_Values) override
+	{
+		for (int z = 0; z < SizeZ; z++)
+		{
+			int BaseZ = a_MinZ + z;
+			for (int x = 0; x < SizeX; x++)
+			{
+				a_Values[x + SizeX * z] = (m_Noise.IntNoise2DInt(a_MinX + x, BaseZ) / 7) % Range;
+			}
+		}  // for z
+	}
+};
+
+
+
+
+
+
+/** Decides between the ocean and landmass biomes.
+Has a threshold (in percent) of how much land, the larger the threshold, the more land.
+Generates 0 for ocean, biome group ID for landmass. */
+template <int SizeX, int SizeZ = SizeX>
+class cIntLandOcean :
+	public cIntGenWithNoise<SizeX, SizeZ>
+{
+	typedef cIntGenWithNoise<SizeX, SizeZ> super;
+
+public:
+	cIntLandOcean(int a_Seed, int a_Threshold) :
+		super(a_Seed),
+		m_Threshold(a_Threshold)
+	{
+	}
+
+
+	virtual void GetInts(int a_MinX, int a_MinZ, Values & a_Values) override
+	{
+		for (int z = 0; z < SizeZ; z++)
+		{
+			int BaseZ = a_MinZ + z;
+			for (int x = 0; x < SizeX; x++)
+			{
+				int rnd = (m_Noise.IntNoise2DInt(a_MinX + x, BaseZ) / 7);
+				a_Values[x + SizeX * z] = ((rnd % 100) < m_Threshold) ? ((rnd / 128) % bgMax + 1) : 0;
+			}
+		}
+	}
+
+protected:
+	int m_Threshold;
+};
+
+
+
+
+
+template <int SizeX, int SizeZ = SizeX>
+class cIntGenZoom :
+	public cIntGenWithNoise<SizeX, SizeZ>
+{
+	typedef cIntGenWithNoise<SizeX, SizeZ> super;
+
+protected:
+	static const int m_LowerSizeX = (SizeX / 2) + 2;
+	static const int m_LowerSizeZ = (SizeZ / 2) + 2;
+
+public:
+	typedef cIntGenPtr<m_LowerSizeX, m_LowerSizeZ> Underlying;
+
+
+	cIntGenZoom(int a_Seed, Underlying a_UnderlyingGen) :
+		super(a_Seed),
+		m_UnderlyingGen(a_UnderlyingGen)
+	{
+	}
+
+
+	virtual void GetInts(int a_MinX, int a_MinZ, Values & a_Values) override
+	{
+		// Generate the underlying data with half the resolution:
+		int lowerMinX = a_MinX >> 1;
+		int lowerMinZ = a_MinZ >> 1;
+		int Underlying[m_LowerSizeX * m_LowerSizeZ];
+		m_UnderlyingGen->GetInts(lowerMinX, lowerMinZ, Underlying);
+		const int lowStepX = (m_LowerSizeX - 1) * 2;
+		const int lowStepZ = (m_LowerSizeZ - 1) * 2;
+		int Cache[lowStepX * lowStepZ];
+
+		// Discreet-interpolate the values into twice the size:
+		for (int z = 0; z < m_LowerSizeZ - 1; ++z)
+		{
+			int idx = (z * 2) * lowStepX;
+			int PrevZ0 = Underlying[z * m_LowerSizeX];
+			int PrevZ1 = Underlying[(z + 1) * m_LowerSizeX];
+
+			for (int x = 0; x < m_LowerSizeX - 1; ++x)
+			{
+				int ValX1Z0 = Underlying[x + 1 + z * m_LowerSizeX];
+				int ValX1Z1 = Underlying[x + 1 + (z + 1) * m_LowerSizeX];
+				int RndX = (x + lowerMinX) * 2;
+				int RndZ = (z + lowerMinZ) * 2;
+				Cache[idx] = PrevZ0;
+				Cache[idx + lowStepX] = ChooseRandomOne(RndX, RndZ, PrevZ0, PrevZ1);
+				idx++;
+				Cache[idx] = ChooseRandomOne(RndX, RndZ, PrevZ0, ValX1Z0);
+				Cache[idx + lowStepX] = ChooseRandomOne(RndX, RndZ, PrevZ0, ValX1Z0, PrevZ1, ValX1Z1);
+				idx++;
+				PrevZ0 = ValX1Z0;
+				PrevZ1 = ValX1Z1;
+			}
+		}
+
+		// Copy from Cache into a_Values; take into account the even/odd offsets in a_Min:
+		for (int z = 0; z < SizeZ; ++z)
+		{
+			memcpy(a_Values + z * SizeX, Cache + (z + (a_MinZ & 1)) * lowStepX + (a_MinX & 1), SizeX * sizeof(int));
+		}
+	}
+
+protected:
+	Underlying m_UnderlyingGen;
+};
+
+
+
+
+
+template <int SizeX, int SizeZ = SizeX>
+class cIntGenSmooth :
+	public cIntGenWithNoise<SizeX, SizeZ>
+{
+	typedef cIntGenWithNoise<SizeX, SizeZ> super;
+	static const int m_UnderlyingSizeX = SizeX + 2;
+	static const int m_UnderlyingSizeZ = SizeZ + 2;
+
+public:
+	typedef cIntGenPtr<m_UnderlyingSizeX, m_UnderlyingSizeZ> Underlying;
+
+
+	cIntGenSmooth(int a_Seed, Underlying a_Underlying) :
+		super(a_Seed),
+		m_Underlying(a_Underlying)
+	{
+	}
+
+
+	virtual void GetInts(int a_MinX, int a_MinZ, Values & a_Values) override
+	{
+		// Generate the underlying values:
+		int Cache[(SizeX + 2) * (SizeZ + 2)];
+		m_Underlying->GetInts(a_MinX - 1, a_MinZ - 1, Cache);
+
+		// Smooth - for each square check if the surroundings are the same, if so, expand them diagonally.
+		// Also get rid of single-pixel irregularities (A-B-A):
+		for (int z = 0; z < SizeZ; z++)
+		{
+			int NoiseZ = a_MinZ + z;
+			for (int x = 0; x < SizeX; x++)
+			{
+				int val   = Cache[x + 1 + (z + 1) * m_UnderlyingSizeX];
+				int Above = Cache[x + 1 +  z      * m_UnderlyingSizeX];
+				int Below = Cache[x + 1 + (z + 2) * m_UnderlyingSizeX];
+				int Left  = Cache[x     + (z + 1) * m_UnderlyingSizeX];
+				int Right = Cache[x + 2 + (z + 1) * m_UnderlyingSizeX];
+
+				if ((Left == Right) && (Above == Below))
+				{
+					if (((m_Noise.IntNoise2DInt(a_MinX + x, NoiseZ) / 7) % 2) == 0)
+					{
+						val = Left;
+					}
+					else
+					{
+						val = Above;
+					}
+				}
+				else
+				{
+					if (Left == Right)
+					{
+						val = Left;
+					}
+
+					if (Above == Below)
+					{
+						val = Above;
+					}
+				}
+
+				a_Values[x + z * SizeX] = val;
+			}
+		}
+	}
+
+protected:
+	Underlying m_Underlying;
+};
+
+
+
+
+
+template<int SizeX, int SizeZ = SizeX>
+class cIntGenBeaches :
+	public cIntGen<SizeX, SizeZ>
+{
+	typedef cIntGen<SizeX, SizeZ> super;
+	static const int m_UnderlyingSizeX = SizeX + 2;
+	static const int m_UnderlyingSizeZ = SizeZ + 2;
+
+public:
+	typedef cIntGenPtr<m_UnderlyingSizeX, m_UnderlyingSizeZ> Underlying;
+
+
+	cIntGenBeaches(Underlying a_Underlying) :
+		m_Underlying(a_Underlying)
+	{
+	}
+
+
+	virtual void GetInts(int a_MinX, int a_MinZ, Values & a_Values) override
+	{
+		// Map for biome -> its beach:
+		static const int ToBeach[] =
+		{
+			/* biOcean            */ biOcean,
+			/* biPlains           */ biBeach,
+			/* biDesert           */ biBeach,
+			/* biExtremeHills     */ biStoneBeach,
+			/* biForest           */ biBeach,
+			/* biTaiga            */ biColdBeach,
+			/* biSwampland        */ biSwampland,
+			/* biRiver            */ biRiver,
+			/* biNether           */ biNether,
+			/* biEnd              */ biEnd,
+			/* biFrozenOcean      */ biColdBeach,
+			/* biFrozenRiver      */ biColdBeach,
+			/* biIcePlains        */ biColdBeach,
+			/* biIceMountains     */ biColdBeach,
+			/* biMushroomIsland   */ biMushroomShore,
+			/* biMushroomShore    */ biMushroomShore,
+			/* biBeach            */ biBeach,
+			/* biDesertHills      */ biBeach,
+			/* biForestHills      */ biBeach,
+			/* biTaigaHills       */ biColdBeach,
+			/* biExtremeHillsEdge */ biStoneBeach,
+			/* biJungle           */ biBeach,
+			/* biJungleHills      */ biBeach,
+			/* biJungleEdge       */ biBeach,
+			/* biDeepOcean        */ biOcean,
+			/* biStoneBeach       */ biStoneBeach,
+			/* biColdBeach        */ biColdBeach,
+			/* biBirchForest      */ biBeach,
+			/* biBirchForestHills */ biBeach,
+			/* biRoofedForest     */ biBeach,
+			/* biColdTaiga        */ biColdBeach,
+			/* biColdTaigaHills   */ biColdBeach,
+			/* biMegaTaiga        */ biStoneBeach,
+			/* biMegaTaigaHills   */ biStoneBeach,
+			/* biExtremeHillsPlus */ biStoneBeach,
+			/* biSavanna          */ biBeach,
+			/* biSavannaPlateau   */ biBeach,
+			/* biMesa             */ biMesa,
+			/* biMesaPlateauF     */ biMesa,
+			/* biMesaPlateau      */ biMesa,
+		};
+
+		// Generate the underlying values:
+		int Cache[m_UnderlyingSizeX * m_UnderlyingSizeZ];
+		m_Underlying->GetInts(a_MinX - 1, a_MinZ - 1, Cache);
+
+		// Add beaches between ocean and biomes:
+		for (int z = 0; z < SizeZ; z++)
+		{
+			for (int x = 0; x < SizeX; x++)
+			{
+				int val = Cache[x + 1 + (z + 1) * m_UnderlyingSizeX];
+				int Above = Cache[x + 1 + z * m_UnderlyingSizeX];
+				int Below = Cache[x + 1 + (z + 2) * m_UnderlyingSizeX];
+				int Left  = Cache[x     + (z + 1) * m_UnderlyingSizeX];
+				int Right = Cache[x + 2 + (z + 1) * m_UnderlyingSizeX];
+				if (!IsBiomeOcean(val))
+				{
+					if (IsBiomeOcean(Above) || IsBiomeOcean(Below) || IsBiomeOcean(Left) || IsBiomeOcean(Right))
+					{
+						val = ToBeach[(val % 128) % ARRAYCOUNT(ToBeach)];
+					}
+				}
+				a_Values[x + z * SizeX] = val;
+			}
+		}
+	}
+
+protected:
+	Underlying m_Underlying;
+};
+
+
+
+
+
+/** Generates the underlying numbers and then randomly changes some zeroes into nonzeroes. */
+template <int SizeX, int SizeZ = SizeX>
+class cIntGenAddIslands :
+	public cIntGenWithNoise<SizeX, SizeZ>
+{
+	typedef cIntGenWithNoise<SizeX, SizeZ> super;
+
+public:
+	typedef cIntGenPtr<SizeX, SizeZ> Underlying;
+
+
+	cIntGenAddIslands(int a_Seed, int a_Threshold, Underlying a_Underlying) :
+		super(a_Seed),
+		m_Threshold(a_Threshold),
+		m_Underlying(a_Underlying)
+	{
+	}
+
+
+	virtual void GetInts(int a_MinX, int a_MinZ, Values & a_Values) override
+	{
+		m_Underlying->GetInts(a_MinX, a_MinZ, a_Values);
+		for (int z = 0; z < SizeZ; z++)
+		{
+			for (int x = 0; x < SizeX; x++)
+			{
+				if (a_Values[x + z * SizeX] == 0)
+				{
+					int rnd = m_Noise.IntNoise2DInt(a_MinX + x, a_MinZ + z) / 7;
+					if (rnd % 100 < m_Threshold)
+					{
+						a_Values[x + z * SizeX] = (rnd / 100) % 4;
+					}
+				}
+			}
+		}
+	}
+
+protected:
+	int m_Threshold;
+
+	Underlying m_Underlying;
+};
+
+
+
+
+
+/** A filter that adds an edge biome group between two biome groups that need an edge between them. */
+template <int SizeX, int SizeZ = SizeX>
+class cIntGenBiomeGroupEdges :
+	public cIntGen<SizeX, SizeZ>
+{
+	typedef cIntGen<SizeX, SizeZ> super;
+
+	static const int m_UnderlyingSizeX = SizeX + 2;
+	static const int m_UnderlyingSizeZ = SizeZ + 2;
+
+public:
+
+	typedef cIntGenPtr<m_UnderlyingSizeX, m_UnderlyingSizeZ> Underlying;
+
+	cIntGenBiomeGroupEdges(Underlying a_Underlying) :
+		m_Underlying(a_Underlying)
+	{
+	}
+
+
+	virtual void GetInts(int a_MinX, int a_MinZ, Values & a_Values)
+	{
+		// Generate the underlying biome groups:
+		int Cache[m_UnderlyingSizeX * m_UnderlyingSizeZ];
+		m_Underlying->GetInts(a_MinX, a_MinZ, Cache);
+
+		// Change the biomes on incompatible edges into an edge biome:
+		for (int z = 0; z < SizeZ; z++)
+		{
+			for (int x = 0; x < SizeX; x++)
+			{
+				int v = Cache[x + 1 + (z + 1) * m_UnderlyingSizeX];
+				int Above = Cache[x + 1 + z * m_UnderlyingSizeX];
+				int Below = Cache[x + 1 + (z + 2) * m_UnderlyingSizeX];
+				int Left  = Cache[x     + (z + 1) * m_UnderlyingSizeX];
+				int Right = Cache[x + 2 + (z + 1) * m_UnderlyingSizeX];
+				switch (v)
+				{
+					// Oceans don't need any edges:
+					case bgOcean:
+					{
+						v = bgOcean;
+						break;
+					}
+
+					// Desert should neighbor only oceans, desert and temperates; change to temperate when another:
+					case bgDesert:
+					{
+						if (
+							!IsDesertCompatible(Above) ||
+							!IsDesertCompatible(Below) ||
+							!IsDesertCompatible(Left) ||
+							!IsDesertCompatible(Right)
+						)
+						{
+							v = bgTemperate;
+						}
+						break;
+					}
+
+					// Ice should not neighbor deserts; change to temperate:
+					case bgIce:
+					{
+						if (
+							(Above == bgDesert) ||
+							(Below == bgDesert) ||
+							(Left == bgDesert) ||
+							(Right == bgDesert)
+						)
+						{
+							v = bgTemperate;
+						}
+						break;
+					}
+
+					// Jungle should not neighbor Desert or Ice; change to temperate:
+					case bgJungle:
+					{
+						if (
+							!IsJungleCompatible(Above) ||
+							!IsJungleCompatible(Below) ||
+							!IsJungleCompatible(Left) ||
+							!IsJungleCompatible(Right)
+						)
+						{
+							v = bgTemperate;
+						}
+					}
+				}
+				a_Values[x + z * SizeX] = v;
+			}  // for x
+		}  // for z
+	}
+
+protected:
+	Underlying m_Underlying;
+
+
+	inline bool IsDesertCompatible(int a_BiomeGroup)
+	{
+		return ((a_BiomeGroup == bgOcean) || (a_BiomeGroup == bgDesert) || (a_BiomeGroup == bgTemperate));
+	}
+
+	inline bool IsJungleCompatible(int a_BiomeGroup)
+	{
+		return ((a_BiomeGroup != bgDesert) && (a_BiomeGroup != bgIce));
+	}
+};
+
+
+
+
+
+template <int SizeX, int SizeZ = SizeX>
+class cIntGenBiomes :
+	public cIntGenWithNoise<SizeX, SizeZ>
+{
+	typedef cIntGenWithNoise<SizeX, SizeZ> super;
+
+public:
+	typedef cIntGenPtr<SizeX, SizeZ> Underlying;
+
+
+	cIntGenBiomes(int a_Seed, Underlying a_Underlying) :
+		super(a_Seed),
+		m_Underlying(a_Underlying)
+	{
+	}
+
+
+	virtual void GetInts(int a_MinX, int a_MinZ, Values & a_Values) override
+	{
+		// Define the per-biome-group biomes:
+		static const int OceanBiomes[] =
+		{
+			biOcean, // biDeepOcean,
+		};
+
+		static const int DesertBiomes[] =
+		{
+			biDesert, biDesert, biSavanna, biPlains,
+		};
+
+		static const int TemperateBiomes[] =
+		{
+			biForest, biRoofedForest, biExtremeHills, biPlains, biBirchForest, biSwampland,
+		};
+
+		static const int MountainBiomes[] =
+		{
+			biExtremeHills, biForest, biTaiga, biPlains,
+		};
+
+		static const int JungleBiomes[] =
+		{
+			biJungle, biJungle, biForest,
+		};
+
+		static const int IceBiomes[] =
+		{
+			biIcePlains, biIcePlains, biColdTaiga,
+		};
+
+		static const cBiomesInGroups BiomesInGroups[] =
+		{
+			{ static_cast<int>(ARRAYCOUNT(OceanBiomes)),     OceanBiomes},
+			{ static_cast<int>(ARRAYCOUNT(DesertBiomes)),    DesertBiomes},
+			{ static_cast<int>(ARRAYCOUNT(TemperateBiomes)), TemperateBiomes},
+			{ static_cast<int>(ARRAYCOUNT(MountainBiomes)),  MountainBiomes},
+			{ static_cast<int>(ARRAYCOUNT(JungleBiomes)),    JungleBiomes},
+			{ static_cast<int>(ARRAYCOUNT(IceBiomes)),       IceBiomes},
+		};
+
+		// Generate the underlying values, representing biome groups:
+		m_Underlying->GetInts(a_MinX, a_MinZ, a_Values);
+
+		// Overwrite each biome group with a random biome from that group:
+		for (int z = 0; z < SizeZ; z++)
+		{
+			int IdxZ = z * SizeX;
+			for (int x = 0; x < SizeX; x++)
+			{
+				int val = a_Values[x + IdxZ];
+				const cBiomesInGroups & Biomes = BiomesInGroups[val % ARRAYCOUNT(BiomesInGroups)];
+				int rnd = (m_Noise.IntNoise2DInt(x + a_MinX, z + a_MinZ) / 7);
+				a_Values[x + IdxZ] = Biomes.Biomes[rnd % Biomes.Count];
+			}
+		}
+	}
+
+protected:
+
+	struct cBiomesInGroups
+	{
+		const int Count;
+		const int * Biomes;
+	};
+
+
+	/** The underlying int generator */
+	Underlying m_Underlying;
+};
+
+
+
+
+
+template <int SizeX, int SizeZ = SizeX>
+class cIntGenReplaceRandomly :
+	public cIntGenWithNoise<SizeX, SizeZ>
+{
+	typedef cIntGenWithNoise<SizeX, SizeZ> super;
+
+public:
+	typedef cIntGenPtr<SizeX, SizeZ> Underlying;
+
+
+	cIntGenReplaceRandomly(int a_From, int a_To, int a_Chance, int a_Seed, Underlying a_Underlying) :
+		super(a_Seed),
+		m_From(a_From),
+		m_To(a_To),
+		m_Chance(a_Chance),
+		m_Underlying(a_Underlying)
+	{
+	}
+
+
+	virtual void GetInts(int a_MinX, int a_MinZ, Values & a_Values) override
+	{
+		// Generate the underlying values:
+		m_Underlying->GetInts(a_MinX, a_MinZ, a_Values);
+
+		// Replace some of the values:
+		for (int z = 0; z < SizeZ; z++)
+		{
+			int idxZ = z * SizeX;
+			for (int x = 0; x < SizeX; x++)
+			{
+				int idx = x + idxZ;
+				if (a_Values[idx] == m_From)
+				{
+					int rnd = m_Noise.IntNoise2DInt(x + a_MinX, z + a_MinZ) / 7;
+					if (rnd % 100 < m_Chance)
+					{
+						a_Values[idx] = m_To;
+					}
+				}
+			}
+		}  // for z
+	}
+
+
+protected:
+	int m_From;
+	int m_To;
+	int m_Chance;
+	Underlying m_Underlying;
+};
+
+
+
+
+
+/** Mixer that joins together finalized biomes and rivers.
+It first checks for oceans; if there's no ocean, it checks for a river. */
+template <int SizeX, int SizeZ = SizeX>
+class cIntGenMixRivers:
+	public cIntGen<SizeX, SizeZ>
+{
+	typedef cIntGen<SizeX, SizeZ> super;
+
+public:
+	typedef cIntGenPtr<SizeX, SizeZ> Underlying;
+
+
+	cIntGenMixRivers(Underlying a_Biomes, Underlying a_Rivers):
+		m_Biomes(a_Biomes),
+		m_Rivers(a_Rivers)
+	{
+	}
+
+
+	virtual void GetInts(int a_MinX, int a_MinZ, Values & a_Values) override
+	{
+		// Generate the underlying data:
+		m_Biomes->GetInts(a_MinX, a_MinZ, a_Values);
+		Values Rivers;
+		m_Rivers->GetInts(a_MinX, a_MinZ, Rivers);
+
+		// Mix the values:
+		for (int z = 0; z < SizeZ; z++)
+		{
+			int idxZ = z * SizeX;
+			for (int x = 0; x < SizeX; x++)
+			{
+				int idx = x + idxZ;
+				if (IsBiomeOcean(a_Values[idx]))
+				{
+					// Oceans are kept without any changes
+					continue;
+				}
+				if (Rivers[idx] != biRiver)
+				{
+					// There's no river, keep the current value
+					continue;
+				}
+
+				// There's a river, change the output to a river or a frozen river, based on the original biome:
+				if (IsBiomeVeryCold((EMCSBiome)a_Values[idx]))
+				{
+					a_Values[idx] = biFrozenRiver;
+				}
+				else
+				{
+					a_Values[idx] = biRiver;
+				}
+			}  // for x
+		}  // for z
+	}
+
+protected:
+	Underlying m_Biomes;
+	Underlying m_Rivers;
+};
+
+
+
+
+
+/** Generates a river based on the underlying data.
+This is basically an edge detector over the underlying data. The rivers are the edges where the underlying data
+changes from one pixel to its neighbor. */
+template <int SizeX, int SizeZ = SizeX>
+class cIntGenRiver:
+	public cIntGenWithNoise<SizeX, SizeZ>
+{
+	typedef cIntGenWithNoise<SizeX, SizeZ> super;
+	static const int UnderlyingSizeX = SizeX + 2;
+	static const int UnderlyingSizeZ = SizeZ + 2;
+
+public:
+	typedef cIntGenPtr<UnderlyingSizeX, UnderlyingSizeZ> Underlying;
+
+
+	cIntGenRiver(int a_Seed, Underlying a_Underlying):
+		super(a_Seed),
+		m_Underlying(a_Underlying)
+	{
+	}
+
+
+	virtual void GetInts(int a_MinX, int a_MinZ, Values & a_Values) override
+	{
+		// Generate the underlying data:
+		int Cache[UnderlyingSizeX * UnderlyingSizeZ];
+		m_Underlying->GetInts(a_MinX - 1, a_MinZ - 1, Cache);
+
+		// Detect the edges:
+		for (int z = 0; z < SizeZ; z++)
+		{
+			for (int x = 0; x < SizeX; x++)
+			{
+				int Above = Cache[x + 1 + z * UnderlyingSizeX];
+				int Below = Cache[x + 1 + (z + 2) * UnderlyingSizeX];
+				int Left  = Cache[x +     (z + 1) * UnderlyingSizeX];
+				int Right = Cache[x + 2 + (z + 1) * UnderlyingSizeX];
+				int val   = Cache[x + 1 + (z + 1) * UnderlyingSizeX];
+
+				if ((val == Above) && (val == Below) && (val == Left) && (val == Right))
+				{
+					val = 0;
+				}
+				else
+				{
+					val = biRiver;
+				}
+				a_Values[x + z * SizeX] = val;
+			}  // for x
+		}  // for z
+	}
+
+protected:
+	Underlying m_Underlying;
+};
+
+
+
+
+
+/** Turns some of the oceans into the specified biome. Used for mushroom and deep ocean.
+The biome is only placed if at least 3 of its neighbors are ocean and only with the specified chance. */
+template <int SizeX, int SizeZ = SizeX>
+class cIntGenAddToOcean:
+	public cIntGenWithNoise<SizeX, SizeZ>
+{
+	typedef cIntGenWithNoise<SizeX, SizeZ> super;
+	static const int UnderlyingSizeX = SizeX + 2;
+	static const int UnderlyingSizeZ = SizeZ + 2;
+
+public:
+	typedef cIntGenPtr<UnderlyingSizeX, UnderlyingSizeZ> Underlying;
+
+
+	cIntGenAddToOcean(int a_Seed, int a_Chance, int a_ToValue, Underlying a_Underlying):
+		super(a_Seed),
+		m_Chance(a_Chance),
+		m_ToValue(a_ToValue),
+		m_Underlying(a_Underlying)
+	{
+	}
+
+
+	virtual void GetInts(int a_MinX, int a_MinZ, Values & a_Values) override
+	{
+		// Generate the underlying data:
+		int Cache[UnderlyingSizeX * UnderlyingSizeZ];
+		m_Underlying->GetInts(a_MinX - 1, a_MinZ - 1, Cache);
+
+		// Add the mushroom islands:
+		for (int z = 0; z < SizeZ; z++)
+		{
+			for (int x = 0; x < SizeX; x++)
+			{
+				int val = Cache[x + 1 + (z + 1) * UnderlyingSizeX];
+				if (!IsBiomeOcean(val))
+				{
+					a_Values[x + z * SizeX] = val;
+					continue;
+				}
+
+				// Count the ocean neighbors:
+				int Above = Cache[x + 1 + z * UnderlyingSizeX];
+				int Below = Cache[x + 1 + (z + 2) * UnderlyingSizeX];
+				int Left  = Cache[x +     (z + 1) * UnderlyingSizeX];
+				int Right = Cache[x + 2 + (z + 1) * UnderlyingSizeX];
+				int NumOceanNeighbors = 0;
+				if (IsBiomeOcean(Above))
+				{
+					NumOceanNeighbors += 1;
+				}
+				if (IsBiomeOcean(Above))
+				{
+					NumOceanNeighbors += 1;
+				}
+				if (IsBiomeOcean(Above))
+				{
+					NumOceanNeighbors += 1;
+				}
+				if (IsBiomeOcean(Above))
+				{
+					NumOceanNeighbors += 1;
+				}
+
+				// If at least 3 ocean neighbors and the chance is right, change:
+				if ((NumOceanNeighbors >= 3) && ((m_Noise.IntNoise2DInt(x + a_MinX, z + a_MinZ) / 7) % 1000 < m_Chance))
+				{
+					a_Values[x + z * SizeX] = m_ToValue;
+				}
+				else
+				{
+					a_Values[x + z * SizeX] = val;
+				}
+			}  // for x
+		}  // for z
+	}
+
+protected:
+	/** Chance, in permille, of changing the biome. */
+	int m_Chance;
+
+	/** The value to change the ocean into. */
+	int m_ToValue;
+
+	Underlying m_Underlying;
+};
+
+
+
+