text: 
  // Noise3DGenerator.h
  
  // Declares cNoise3DGenerator and cNoise3DComposable classes, representing 3D-noise-based generators.
  // They generate terrain shape by combining a lerp of two 3D noises with a vertical linear gradient
  // cNoise3DGenerator is obsolete and unmaintained.
  // cNoise3DComposable is used to test parameter combinations for single-biome worlds.
  
  
  
  
  
  #pragma once
  
  #include "ComposableGenerator.h"
  #include "../Noise/Noise.h"
  #include "../Noise/InterpolNoise.h"
  
  
  
  
  
  class cNoise3DGenerator :
  	public cChunkGenerator::cGenerator
  {
  	typedef cChunkGenerator::cGenerator super;
  	
  public:
  	cNoise3DGenerator(cChunkGenerator & a_ChunkGenerator);
  	virtual ~cNoise3DGenerator();
  	
  	virtual void Initialize(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 = 4;
  	static const int UPSCALE_Y = 8;
  	static const int UPSCALE_Z = 4;
  	
  	// 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;
  
  	/** The base 3D noise source for the actual composition */
  	cOctavedNoise<cInterp5DegNoise> m_Perlin;
  
  	/** The noise used for heightmap directing. */
  	cOctavedNoise<cInterp5DegNoise> m_Cubic;
  	
  	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 cTerrainShapeGen
  {
  public:
  	cNoise3DComposable(int a_Seed);
  
  	void Initialize(cIniFile & a_IniFile);
  
  protected:
  	/** The 3D noise that is used to choose between density noise A and B. */
  	cOctavedNoise<cInterpolNoise<Interp5Deg>> m_ChoiceNoise;
  
  	/** Density 3D noise, variant A. */
  	cOctavedNoise<cInterpolNoise<Interp5Deg>> m_DensityNoiseA;
  
  	/** Density 3D noise, variant B. */
  	cOctavedNoise<cInterpolNoise<Interp5Deg>> m_DensityNoiseB;
  
  	/** Heightmap-like noise used to provide variance for low-amplitude biomes. */
  	cOctavedNoise<cInterpolNoise<Interp5Deg>> m_BaseNoise;
  	
  	/** The main parameter of the generator, specifies the slope of the vertical linear gradient.
  	A higher value means a steeper slope and a smaller total amplitude of the generated terrain. */
  	NOISE_DATATYPE m_HeightAmplification;
  
  	/** Where the vertical "center" of the noise should be, as block height. */
  	NOISE_DATATYPE m_MidPoint;
  
  	// Frequency of the 3D noise's first octave:
  	NOISE_DATATYPE m_FrequencyX;
  	NOISE_DATATYPE m_FrequencyY;
  	NOISE_DATATYPE m_FrequencyZ;
  
  	// Frequency of the base terrain noise:
  	NOISE_DATATYPE m_BaseFrequencyX;
  	NOISE_DATATYPE m_BaseFrequencyZ;
  
  	// Frequency of the choice noise:
  	NOISE_DATATYPE m_ChoiceFrequencyX;
  	NOISE_DATATYPE m_ChoiceFrequencyY;
  	NOISE_DATATYPE m_ChoiceFrequencyZ;
  
  	// Threshold for when the values are considered air:
  	NOISE_DATATYPE m_AirThreshold;
  	
  	// Cache for the last calculated chunk (reused between heightmap and composition queries):
  	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 (m_NoiseArray), unless the LastChunk coords are equal to coords given */
  	void GenerateNoiseArrayIfNeeded(int a_ChunkX, int a_ChunkZ);
  	
  	// cTerrainHeightGen overrides:
  	virtual void GenShape(int a_ChunkX, int a_ChunkZ, cChunkDesc::Shape & a_Shape) override;
  	virtual void InitializeShapeGen(cIniFile & a_IniFile) override { Initialize(a_IniFile); }
  } ;
  
  
  
  
  
  class cBiomalNoise3DComposable :
  	public cTerrainShapeGen
  {
  public:
  	cBiomalNoise3DComposable(int a_Seed, cBiomeGenPtr a_BiomeGen);
  
  	void Initialize(cIniFile & a_IniFile);
  
  protected:
  	/** Number of columns around the pixel to query for biomes for averaging. Must be less than or equal to 16. */
  	static const int AVERAGING_SIZE = 9;
  
  	/** Type used for a single parameter across the entire (downscaled) chunk. */
  	typedef NOISE_DATATYPE ChunkParam[5 * 5];
  
  
  	/** The noise that is used to choose between density noise A and B. */
  	cOctavedNoise<cInterpolNoise<Interp5Deg>> m_ChoiceNoise;
  
  	/** Density 3D noise, variant A. */
  	cOctavedNoise<cInterpolNoise<Interp5Deg>> m_DensityNoiseA;
  
  	/** Density 3D noise, variant B. */
  	cOctavedNoise<cInterpolNoise<Interp5Deg>> m_DensityNoiseB;
  
  	/** Heightmap-like noise used to provide variance for low-amplitude biomes. */
  	cOctavedNoise<cInterpolNoise<Interp5Deg>> m_BaseNoise;
  
  	/** The underlying biome generator. */
  	cBiomeGenPtr m_BiomeGen;
  	
  	/** Block height of the sealevel, used for composing the terrain. */
  	int m_SeaLevel;
  
  	// Frequency of the 3D noise's first octave:
  	NOISE_DATATYPE m_FrequencyX;
  	NOISE_DATATYPE m_FrequencyY;
  	NOISE_DATATYPE m_FrequencyZ;
  
  	// Frequency of the base terrain noise:
  	NOISE_DATATYPE m_BaseFrequencyX;
  	NOISE_DATATYPE m_BaseFrequencyZ;
  
  	// Frequency of the choice noise:
  	NOISE_DATATYPE m_ChoiceFrequencyX;
  	NOISE_DATATYPE m_ChoiceFrequencyY;
  	NOISE_DATATYPE m_ChoiceFrequencyZ;
  
  	// Threshold for when the values are considered air:
  	NOISE_DATATYPE m_AirThreshold;
  	
  	// Cache for the last calculated chunk (reused between heightmap and composition queries):
  	int m_LastChunkX;
  	int m_LastChunkZ;
  	NOISE_DATATYPE m_NoiseArray[17 * 17 * 257];  // 257 * x + y + 257 * 17 * z
  
  	/** Weights for summing up neighboring biomes. */
  	NOISE_DATATYPE m_Weight[AVERAGING_SIZE * 2 + 1][AVERAGING_SIZE * 2 + 1];
  
  	/** The sum of m_Weight[]. */
  	NOISE_DATATYPE m_WeightSum;
  	
  	
  	/** Generates the 3D noise array used for terrain generation (m_NoiseArray), unless the LastChunk coords are equal to coords given */
  	void GenerateNoiseArrayIfNeeded(int a_ChunkX, int a_ChunkZ);
  
  	/** Calculates the biome-related parameters for the chunk. */
  	void CalcBiomeParamArrays(int a_ChunkX, int a_ChunkZ, ChunkParam & a_HeightAmp, ChunkParam & a_MidPoint);
  
  	/** Returns the parameters for the specified biome. */
  	void GetBiomeParams(EMCSBiome a_Biome, NOISE_DATATYPE & a_HeightAmp, NOISE_DATATYPE & a_MidPoint);
  	
  	// cTerrainShapeGen overrides:
  	virtual void GenShape(int a_ChunkX, int a_ChunkZ, cChunkDesc::Shape & a_Shape) override;
  	virtual void InitializeShapeGen(cIniFile & a_IniFile) override { Initialize(a_IniFile); }
  } ;
  
  
  
  
  