5 files changed, 162 insertions, 8 deletions

diff --git a/src/Generating/CMakeLists.txt b/src/Generating/CMakeLists.txt
index dcb4bb3a7..a28510d40 100644
--- a/src/Generating/CMakeLists.txt
+++ b/src/Generating/CMakeLists.txt
@@ -31,8 +31,10 @@ SET (SRCS
 	StructGen.cpp
 	TestRailsGen.cpp
 	Trees.cpp
+	TwoHeights.cpp
 	UnderwaterBaseGen.cpp
-	VillageGen.cpp)
+	VillageGen.cpp
+)
 
 SET (HDRS
 	BioGen.h
@@ -65,8 +67,10 @@ SET (HDRS
 	StructGen.h
 	TestRailsGen.h
 	Trees.h
+	TwoHeights.h
 	UnderwaterBaseGen.h
-	VillageGen.h)
+	VillageGen.h
+)
 
 if(NOT MSVC)
 	add_library(Generating ${SRCS} ${HDRS})
diff --git a/src/Generating/HeiGen.h b/src/Generating/HeiGen.h
index 9c99a9326..62bb227c6 100644
--- a/src/Generating/HeiGen.h
+++ b/src/Generating/HeiGen.h
@@ -170,7 +170,11 @@ public:
 		m_BiomeGen(a_BiomeGen)
 	{
 	}
-	
+
+	// cTerrainHeightGen overrides:
+	virtual void GenHeightMap(int a_ChunkX, int a_ChunkZ, cChunkDef::HeightMap & a_HeightMap) override;
+	virtual void InitializeHeightGen(cIniFile & a_IniFile) override;
+
 protected:
 
 	typedef cChunkDef::BiomeMap BiomeNeighbors[3][3];
@@ -187,11 +191,8 @@ protected:
 		float m_BaseHeight;
 	} ;
 	static const sGenParam m_GenParam[256];
-	
-	// 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);
 } ;
 
diff --git a/src/Generating/ShapeGen.cpp b/src/Generating/ShapeGen.cpp
index 750b34e10..45a9c3b93 100644
--- a/src/Generating/ShapeGen.cpp
+++ b/src/Generating/ShapeGen.cpp
@@ -9,6 +9,7 @@
 #include "DistortedHeightmap.h"
 #include "EndGen.h"
 #include "Noise3DGenerator.h"
+#include "TwoHeights.h"
 
 
 
@@ -121,6 +122,10 @@ cTerrainShapeGenPtr cTerrainShapeGen::CreateShapeGen(cIniFile & a_IniFile, cBiom
 	{
 		res = std::make_shared<cNoise3DComposable>(a_Seed);
 	}
+	else if (NoCaseCompare(shapeGenName, "TwoHeights") == 0)
+	{
+		res = CreateShapeGenTwoHeights(a_Seed, a_BiomeGen);
+	}
 	else
 	{
 		// No match found, force-set the default and retry
diff --git a/src/Generating/TwoHeights.cpp b/src/Generating/TwoHeights.cpp
new file mode 100644
index 000000000..e75c301de
--- /dev/null
+++ b/src/Generating/TwoHeights.cpp
@@ -0,0 +1,121 @@
+
+// TwoHeights.cpp
+
+// Implements the cTwoHeights class representing the terrain shape generator using two switched heightmaps
+
+#include "Globals.h"
+#include "TwoHeights.h"
+#include "../Noise/InterpolNoise.h"
+#include "HeiGen.h"
+#include "../LinearUpscale.h"
+#include "../IniFile.h"
+
+
+
+
+
+class cTwoHeights:
+	public cTerrainShapeGen
+{
+	typedef cTerrainShapeGen super;
+public:
+	cTwoHeights(int a_Seed, cBiomeGenPtr a_BiomeGen):
+		m_Seed(a_Seed),
+		m_Choice(a_Seed),
+		m_HeightA(a_Seed + 1, a_BiomeGen),
+		m_HeightB(a_Seed + 2, a_BiomeGen)
+	{
+	}
+
+
+	// cTerrainShapeGen override:
+	virtual void GenShape(int a_ChunkX, int a_ChunkZ, cChunkDesc::Shape & a_Shape) override
+	{
+		// Generate the two heightmaps:
+		cChunkDef::HeightMap heightsA;
+		cChunkDef::HeightMap heightsB;
+		m_HeightA.GenHeightMap(a_ChunkX, a_ChunkZ, heightsA);
+		m_HeightB.GenHeightMap(a_ChunkX, a_ChunkZ, heightsB);
+
+		// Generate the choice noise:
+		NOISE_DATATYPE smallChoice[33 * 5 * 5];
+		NOISE_DATATYPE workspace[33 * 5 * 5];
+		NOISE_DATATYPE startX = 0;
+		NOISE_DATATYPE endX = 256 * m_FrequencyY;
+		NOISE_DATATYPE startY =  a_ChunkX * cChunkDef::Width * m_FrequencyX;
+		NOISE_DATATYPE endY   = (a_ChunkX * cChunkDef::Width + cChunkDef::Width + 1) * m_FrequencyX;
+		NOISE_DATATYPE startZ =  a_ChunkZ * cChunkDef::Width * m_FrequencyZ;
+		NOISE_DATATYPE endZ   = (a_ChunkZ * cChunkDef::Width + cChunkDef::Width + 1) * m_FrequencyZ;
+		m_Choice.Generate3D(smallChoice, 33, 5, 5, startX, endX, startY, endY, startZ, endZ, workspace);
+		NOISE_DATATYPE choice[257 * 17 * 17];
+		LinearUpscale3DArray(smallChoice, 33, 5, 5, choice, 8, 4, 4);
+
+		// Generate the shape:
+		int idxShape = 0;
+		for (int z = 0; z < cChunkDef::Width; z++)
+		{
+			for (int x = 0; x < cChunkDef::Width; x++)
+			{
+				int idxChoice = 257 * 17 * z + 257 * x;
+				NOISE_DATATYPE heightA = static_cast<NOISE_DATATYPE>(cChunkDef::GetHeight(heightsA, x, z));
+				NOISE_DATATYPE heightB = static_cast<NOISE_DATATYPE>(cChunkDef::GetHeight(heightsB, x, z));
+				for (int y = 0; y < cChunkDef::Height; y++)
+				{
+					int height = static_cast<int>(ClampedLerp(heightA, heightB, choice[idxChoice++]));
+					a_Shape[idxShape++] = (y < height) ? 1 : 0;
+				}
+			}  // for x
+		}  // for z
+	}
+
+
+	virtual void InitializeShapeGen(cIniFile & a_IniFile)
+	{
+		m_FrequencyX = static_cast<NOISE_DATATYPE>(a_IniFile.GetValueSetF("Generator", "TwoHeightsFrequencyX", 40));
+		m_FrequencyY = static_cast<NOISE_DATATYPE>(a_IniFile.GetValueSetF("Generator", "TwoHeightsFrequencyY", 40));
+		m_FrequencyZ = static_cast<NOISE_DATATYPE>(a_IniFile.GetValueSetF("Generator", "TwoHeightsFrequencyZ", 40));
+
+		// Initialize the two underlying height generators from an empty INI file:
+		cIniFile empty;
+		m_HeightA.InitializeHeightGen(empty);
+		m_HeightB.InitializeHeightGen(empty);
+
+		// Add the choice octaves:
+		NOISE_DATATYPE freq = 0.001f;
+		NOISE_DATATYPE ampl = 1;
+		for (int i = 0; i < 4; i++)
+		{
+			m_Choice.AddOctave(freq, ampl);
+			freq = freq * 2;
+			ampl = ampl / 2;
+		}
+	}
+
+protected:
+	int m_Seed;
+
+	/** The noise used to decide between the two heightmaps. */
+	cOctavedNoise<cInterpolNoise<Interp5Deg>> m_Choice;
+
+	/** The first height generator. */
+	cHeiGenBiomal m_HeightA;
+
+	/** The second height generator. */
+	cHeiGenBiomal m_HeightB;
+
+	/** The base frequencies for m_Choice in each of the world axis directions. */
+	NOISE_DATATYPE m_FrequencyX, m_FrequencyY, m_FrequencyZ;
+};
+
+
+
+
+
+cTerrainShapeGenPtr CreateShapeGenTwoHeights(int a_Seed, cBiomeGenPtr a_BiomeGen)
+{
+	return std::make_shared<cTwoHeights>(a_Seed, a_BiomeGen);
+}
+
+
+
+
diff --git a/src/Generating/TwoHeights.h b/src/Generating/TwoHeights.h
new file mode 100644
index 000000000..353598011
--- /dev/null
+++ b/src/Generating/TwoHeights.h
@@ -0,0 +1,23 @@
+
+// TwoHeights.h
+
+// Declares the function to create a new instance of the cTwoHeights terrain shape generator
+
+
+
+
+
+#pragma once
+
+#include "ComposableGenerator.h"
+
+
+
+
+/** Creates and returns a new instance of the cTwoHeights terrain shape generator.
+The instance must be Initialize()-d before it is used. */
+extern cTerrainShapeGenPtr CreateShapeGenTwoHeights(int a_Seed, cBiomeGenPtr a_BiomeGen);
+
+
+
+