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diff --git a/src/Noise/InterpolNoise.h b/src/Noise/InterpolNoise.h
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+++ b/src/Noise/InterpolNoise.h
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+
+// InterpolNoise.h
+
+// Implements the cInterpolNoise class template representing a noise that interpolates the values between integer coords from a single set of neighbors
+
+
+
+
+
+#pragma once
+
+#include "Noise.h"
+
+#define FAST_FLOOR(x) (((x) < 0) ? (((int)x) - 1) : ((int)x))
+
+
+
+
+
+////////////////////////////////////////////////////////////////////////////////
+// cInterpolCell3D:
+
+/** Holds a cache of the last calculated integral noise values and interpolates between them en masse.
+Provides a massive optimization for cInterpolNoise.
+Works by calculating multiple noise values (that have the same integral noise coords) at once. The underlying noise values
+needn't be recalculated for these values, only the interpolation is done within the unit cube. */
+template <typename T>
+class cInterpolCell3D
+{
+public:
+	cInterpolCell3D(
+		const cNoise & a_Noise,                 ///< Noise to use for generating the random values
+		NOISE_DATATYPE * a_Array,               ///< Array to generate into [x + a_SizeX * y]
+		int a_SizeX, int a_SizeY, int a_SizeZ,  ///< Count of the array, in each direction
+		const NOISE_DATATYPE * a_FracX,         ///< Pointer to the array that stores the X fractional values
+		const NOISE_DATATYPE * a_FracY,         ///< Pointer to the attay that stores the Y fractional values
+		const NOISE_DATATYPE * a_FracZ          ///< Pointer to the array that stores the Z fractional values
+	):
+		m_Noise(a_Noise),
+		m_WorkRnds(&m_Workspace1),
+		m_CurFloorX(0),
+		m_CurFloorY(0),
+		m_CurFloorZ(0),
+		m_Array(a_Array),
+		m_SizeX(a_SizeX),
+		m_SizeY(a_SizeY),
+		m_SizeZ(a_SizeZ),
+		m_FracX(a_FracX),
+		m_FracY(a_FracY),
+		m_FracZ(a_FracZ)
+	{
+	}
+
+
+	/** Generates part of the output array using current m_WorkRnds[]. */
+	void Generate(
+		int a_FromX, int a_ToX,
+		int a_FromY, int a_ToY,
+		int a_FromZ, int a_ToZ
+	)
+	{
+		for (int z = a_FromZ; z < a_ToZ; z++)
+		{
+			int idxZ = z * m_SizeX * m_SizeY;
+			NOISE_DATATYPE Interp2[2][2];
+			NOISE_DATATYPE FracZ = T::coeff(m_FracZ[z]);
+			for (int x = 0; x < 2; x++)
+			{
+				for (int y = 0; y < 2; y++)
+				{
+					Interp2[x][y] = Lerp((*m_WorkRnds)[x][y][0], (*m_WorkRnds)[x][y][1], FracZ);
+				}
+			}
+			for (int y = a_FromY; y < a_ToY; y++)
+			{
+				NOISE_DATATYPE Interp[2];
+				NOISE_DATATYPE FracY = T::coeff(m_FracY[y]);
+				Interp[0] = Lerp(Interp2[0][0], Interp2[0][1], FracY);
+				Interp[1] = Lerp(Interp2[1][0], Interp2[1][1], FracY);
+				int idx = idxZ + y * m_SizeX + a_FromX;
+				for (int x = a_FromX; x < a_ToX; x++)
+				{
+					m_Array[idx++] = Lerp(Interp[0], Interp[1], T::coeff(m_FracX[x]));
+				}  // for x
+			}  // for y
+		}  // for z
+	}
+
+
+	/** Initializes m_WorkRnds[] with the specified Floor values. */
+	void InitWorkRnds(int a_FloorX, int a_FloorY, int a_FloorZ)
+	{
+		m_CurFloorX = a_FloorX;
+		m_CurFloorY = a_FloorY;
+		m_CurFloorZ = a_FloorZ;
+		(*m_WorkRnds)[0][0][0] = (NOISE_DATATYPE)m_Noise.IntNoise3D(m_CurFloorX,     m_CurFloorY,     m_CurFloorZ);
+		(*m_WorkRnds)[0][0][1] = (NOISE_DATATYPE)m_Noise.IntNoise3D(m_CurFloorX,     m_CurFloorY,     m_CurFloorZ + 1);
+		(*m_WorkRnds)[0][1][0] = (NOISE_DATATYPE)m_Noise.IntNoise3D(m_CurFloorX,     m_CurFloorY + 1, m_CurFloorZ);
+		(*m_WorkRnds)[0][1][1] = (NOISE_DATATYPE)m_Noise.IntNoise3D(m_CurFloorX,     m_CurFloorY + 1, m_CurFloorZ + 1);
+		(*m_WorkRnds)[1][0][0] = (NOISE_DATATYPE)m_Noise.IntNoise3D(m_CurFloorX + 1, m_CurFloorY,     m_CurFloorZ);
+		(*m_WorkRnds)[1][0][1] = (NOISE_DATATYPE)m_Noise.IntNoise3D(m_CurFloorX + 1, m_CurFloorY,     m_CurFloorZ + 1);
+		(*m_WorkRnds)[1][1][0] = (NOISE_DATATYPE)m_Noise.IntNoise3D(m_CurFloorX + 1, m_CurFloorY + 1, m_CurFloorZ);
+		(*m_WorkRnds)[1][1][1] = (NOISE_DATATYPE)m_Noise.IntNoise3D(m_CurFloorX + 1, m_CurFloorY + 1, m_CurFloorZ + 1);
+	}
+
+
+	/** Updates m_WorkRnds[] for the new Floor values. */
+	void Move(int a_NewFloorX, int a_NewFloorY, int a_NewFloorZ)
+	{
+		// Swap the doublebuffer:
+		int OldFloorX = m_CurFloorX;
+		int OldFloorY = m_CurFloorY;
+		int OldFloorZ = m_CurFloorZ;
+		Workspace * OldWorkRnds = m_WorkRnds;
+		m_WorkRnds = (m_WorkRnds == &m_Workspace1) ? &m_Workspace2 : &m_Workspace1;
+
+		// Reuse as much of the old workspace as possible:
+		// TODO: Try out if simply calculating all 8 elements each time is faster than this monster loop
+		int DiffX = OldFloorX - a_NewFloorX;
+		int DiffY = OldFloorY - a_NewFloorY;
+		int DiffZ = OldFloorZ - a_NewFloorZ;
+		for (int x = 0; x < 2; x++)
+		{
+			int cx = a_NewFloorX + x;
+			int OldX = x - DiffX;  // Where would this X be in the old grid?
+			for (int y = 0; y < 2; y++)
+			{
+				int cy = a_NewFloorY + y;
+				int OldY = y - DiffY;  // Where would this Y be in the old grid?
+				for (int z = 0; z < 2; z++)
+				{
+					int cz = a_NewFloorZ + z;
+					int OldZ = z - DiffZ;
+					if ((OldX >= 0) && (OldX < 2) && (OldY >= 0) && (OldY < 2) && (OldZ >= 0) && (OldZ < 2))
+					{
+						(*m_WorkRnds)[x][y][z] = (*OldWorkRnds)[OldX][OldY][OldZ];
+					}
+					else
+					{
+						(*m_WorkRnds)[x][y][z] = (NOISE_DATATYPE)m_Noise.IntNoise3D(cx, cy, cz);
+					}
+				}  // for z
+			}  // for y
+		}  // for x
+		m_CurFloorX = a_NewFloorX;
+		m_CurFloorY = a_NewFloorY;
+		m_CurFloorZ = a_NewFloorZ;
+	}
+
+protected:
+	typedef NOISE_DATATYPE Workspace[2][2][2];
+
+	/** The noise used for generating the values at integral coords. */
+	const cNoise & m_Noise;
+
+	/** The current random values; points to either m_Workspace1 or m_Workspace2 (doublebuffering) */
+	Workspace * m_WorkRnds;
+
+	/** Buffer 1 for workspace doublebuffering, used in Move() */
+	Workspace m_Workspace1;
+
+	/** Buffer 2 for workspace doublebuffering, used in Move() */
+	Workspace m_Workspace2;
+
+	/** The integral coords of the currently calculated WorkRnds[] */
+	int m_CurFloorX, m_CurFloorY, m_CurFloorZ;
+
+	/** The output array where the noise is calculated. */
+	NOISE_DATATYPE * m_Array;
+
+	/** Dimensions of the output array. */
+	int m_SizeX, m_SizeY, m_SizeZ;
+
+	/** Arrays holding the fractional values of the coords in each direction. */
+	const NOISE_DATATYPE * m_FracX;
+	const NOISE_DATATYPE * m_FracY;
+	const NOISE_DATATYPE * m_FracZ;
+} ;
+
+
+
+
+
+////////////////////////////////////////////////////////////////////////////////
+// cInterpolNoise:
+
+template <typename T>
+class cInterpolNoise
+{
+	/** Maximum size, for each direction, of the generated array. */
+	static const int MAX_SIZE = 256;
+
+public:
+	cInterpolNoise(int a_Seed):
+		m_Noise(a_Seed)
+	{
+	}
+
+
+	/** Sets a new seed for the generators. Relays the seed to the underlying noise. */
+	void SetSeed(int a_Seed)
+	{
+		m_Noise.SetSeed(a_Seed);
+	}
+
+
+	/** Fills a 2D array with the values of the noise. */
+	void Generate2D(
+		NOISE_DATATYPE * a_Array,                        ///< Array to generate into [x + a_SizeX * y]
+		int a_SizeX, int a_SizeY,                        ///< Count of the array, in each direction
+		NOISE_DATATYPE a_StartX, NOISE_DATATYPE a_EndX,  ///< Noise-space coords of the array in the X direction
+		NOISE_DATATYPE a_StartY, NOISE_DATATYPE a_EndY   ///< Noise-space coords of the array in the Y direction
+	) const
+	{
+		// Check params:
+		ASSERT(a_SizeX > 1);
+		ASSERT(a_SizeY > 1);
+
+		// Generate the noise:
+		size_t idx = 0;
+		for (int y = 0; y < a_SizeY; y++)
+		{
+			NOISE_DATATYPE ratioY = static_cast<NOISE_DATATYPE>(y) / (a_SizeY - 1);
+			NOISE_DATATYPE noiseY = Lerp(a_StartY, a_EndY, ratioY);
+			int noiseYInt = FAST_FLOOR(noiseY);
+			NOISE_DATATYPE ratioY = typename T(noiseY - static_cast<NOISE_DATATYPE>(noiseYInt));
+			for (int x = 0; x < a_SizeX; x++)
+			{
+				NOISE_DATATYPE ratioX = static_cast<NOISE_DATATYPE>(x) / (a_SizeX - 1);
+				NOISE_DATATYPE noiseX = Lerp(a_StartX, a_EndX, ratioX);
+				int noiseXInt = FAST_FLOOR(noiseX);
+				NOISE_DATATYPE ratioX = typename T(noiseX - static_cast<NOISE_DATATYPE>(noiseXInt));
+
+				NOISE_DATATYPE valx0y0 = m_Noise.IntNoise2D(noiseXInt, noiseYInt);
+				NOISE_DATATYPE valx1y0 = m_Noise.IntNoise2D(noiseXInt + 1, noiseYInt);
+				NOISE_DATATYPE valx0y1 = m_Noise.IntNoise2D(noiseXInt, noiseYInt + 1);
+				NOISE_DATATYPE valx1y1 = m_Noise.IntNoise2D(noiseXInt + 1, noiseYInt + 1);
+				NOISE_DATATYPE valx0 = Lerp(valx0y0, valx0y1, ratioY);
+				NOISE_DATATYPE valx1 = Lerp(valx1y1, valx1y1, ratioY);
+				a_Array[idx++] = Lerp(valx0, valx1, ratioX);
+			}  // for x
+		}  // for y
+	}
+
+
+	/** Fills a 3D array with the values of the noise. */
+	void Generate3D(
+		NOISE_DATATYPE * a_Array,                        ///< Array to generate into [x + a_SizeX * y + a_SizeX * a_SizeY * z]
+		int a_SizeX, int a_SizeY, int a_SizeZ,           ///< Count of the array, in each direction
+		NOISE_DATATYPE a_StartX, NOISE_DATATYPE a_EndX,  ///< Noise-space coords of the array in the X direction
+		NOISE_DATATYPE a_StartY, NOISE_DATATYPE a_EndY,  ///< Noise-space coords of the array in the Y direction
+		NOISE_DATATYPE a_StartZ, NOISE_DATATYPE a_EndZ   ///< Noise-space coords of the array in the Z direction
+	) const
+	{
+		// Check params:
+		ASSERT(a_SizeX > 1);
+		ASSERT(a_SizeY > 1);
+
+		ASSERT(a_SizeX < MAX_SIZE);
+		ASSERT(a_SizeY < MAX_SIZE);
+		ASSERT(a_SizeZ < MAX_SIZE);
+		ASSERT(a_StartX < a_EndX);
+		ASSERT(a_StartY < a_EndY);
+		ASSERT(a_StartZ < a_EndZ);
+
+		// Calculate the integral and fractional parts of each coord:
+		int FloorX[MAX_SIZE];
+		int FloorY[MAX_SIZE];
+		int FloorZ[MAX_SIZE];
+		NOISE_DATATYPE FracX[MAX_SIZE];
+		NOISE_DATATYPE FracY[MAX_SIZE];
+		NOISE_DATATYPE FracZ[MAX_SIZE];
+		int SameX[MAX_SIZE];
+		int SameY[MAX_SIZE];
+		int SameZ[MAX_SIZE];
+		int NumSameX, NumSameY, NumSameZ;
+		CalcFloorFrac(a_SizeX, a_StartX, a_EndX, FloorX, FracX, SameX, NumSameX);
+		CalcFloorFrac(a_SizeY, a_StartY, a_EndY, FloorY, FracY, SameY, NumSameY);
+		CalcFloorFrac(a_SizeZ, a_StartZ, a_EndZ, FloorZ, FracZ, SameZ, NumSameZ);
+
+		cInterpolCell3D<T> Cell(
+			m_Noise, a_Array,
+			a_SizeX, a_SizeY, a_SizeZ,
+			FracX, FracY, FracZ
+		);
+	
+		Cell.InitWorkRnds(FloorX[0], FloorY[0], FloorZ[0]);
+	
+		// Calculate query values using Cell:
+		int FromZ = 0;
+		for (int z = 0; z < NumSameZ; z++)
+		{
+			int ToZ = FromZ + SameZ[z];
+			int CurFloorZ = FloorZ[FromZ];
+			int FromY = 0;
+			for (int y = 0; y < NumSameY; y++)
+			{
+				int ToY = FromY + SameY[y];
+				int CurFloorY = FloorY[FromY];
+				int FromX = 0;
+				for (int x = 0; x < NumSameX; x++)
+				{
+					int ToX = FromX + SameX[x];
+					Cell.Generate(FromX, ToX, FromY, ToY, FromZ, ToZ);
+					Cell.Move(FloorX[ToX], CurFloorY, CurFloorZ);
+					FromX = ToX;
+				}
+				Cell.Move(FloorX[0], FloorY[ToY], CurFloorZ);
+				FromY = ToY;
+			}  // for y
+			Cell.Move(FloorX[0], FloorY[0], FloorZ[ToZ]);
+			FromZ = ToZ;
+		}  // for z
+	}
+
+protected:
+
+	/** The noise used for the underlying value generation. */
+	cNoise m_Noise;
+
+
+	/** Calculates the integral and fractional parts along one axis.
+	a_Floor will receive the integral parts (array of a_Size ints).
+	a_Frac will receive the fractional parts (array of a_Size floats).
+	a_Same will receive the counts of items that have the same integral parts (array of up to a_Size ints).
+	a_NumSame will receive the count of a_Same elements (total count of different integral parts). */
+	void CalcFloorFrac(
+		int a_Size,
+		NOISE_DATATYPE a_Start, NOISE_DATATYPE a_End,
+		int * a_Floor, NOISE_DATATYPE * a_Frac,
+		int * a_Same, int & a_NumSame
+	) const
+	{
+		ASSERT(a_Size > 0);
+
+		// Calculate the floor and frac values:
+		NOISE_DATATYPE val = a_Start;
+		NOISE_DATATYPE dif = (a_End - a_Start) / (a_Size - 1);
+		for (int i = 0; i < a_Size; i++)
+		{
+			a_Floor[i] = FAST_FLOOR(val);
+			a_Frac[i] = val - a_Floor[i];
+			val += dif;
+		}
+
+		// Mark up the same floor values into a_Same / a_NumSame:
+		int CurFloor = a_Floor[0];
+		int LastSame = 0;
+		a_NumSame = 0;
+		for (int i = 1; i < a_Size; i++)
+		{
+			if (a_Floor[i] != CurFloor)
+			{
+				a_Same[a_NumSame] = i - LastSame;
+				LastSame = i;
+				a_NumSame += 1;
+				CurFloor = a_Floor[i];
+			}
+		}  // for i - a_Floor[]
+		if (LastSame < a_Size)
+		{
+			a_Same[a_NumSame] = a_Size - LastSame;
+			a_NumSame += 1;
+		}
+	}
+};
+
+
+
+
+
+/** A fifth-degree curve for interpolating.
+Implemented as a functor for better chance of inlining. */
+struct Interp5Deg
+{
+	static NOISE_DATATYPE coeff(NOISE_DATATYPE a_Val)
+	{
+		return a_Val * a_Val * a_Val * (a_Val * (a_Val * 6 - 15) + 10);
+	}
+};
+
+typedef cInterpolNoise<Interp5Deg> cInterp5DegNoise;
+
+
+