1 files changed, 100 insertions, 5 deletions

diff --git a/src/Noise.h b/src/Noise.h
index b7a90d5b7..3c5caded7 100644
--- a/src/Noise.h
+++ b/src/Noise.h
@@ -140,6 +140,63 @@ protected:
 
 
 
+/** Improved noise, as described by Ken Perlin: http://mrl.nyu.edu/~perlin/paper445.pdf
+Implementation adapted from Perlin's Java implementation: http://mrl.nyu.edu/~perlin/noise/ */
+class cImprovedNoise
+{
+public:
+	/** Constructs a new instance of the noise obbject.
+	Note that this operation is quite expensive (the permutation array being constructed). */
+	cImprovedNoise(int 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;
+	
+	
+	/** 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;
+
+	/** Returns the value at the specified integral coords. Used for raw speed measurement. */
+	NOISE_DATATYPE GetValueAt(int a_X, int a_Y, int a_Z);
+
+protected:
+
+	/** The permutation table used by the noise function. Initialized using seed. */
+	int m_Perm[512];
+
+
+	/** Calculates the fade curve, 6 * t^5 - 15 * t^4 + 10 * t^3. */
+	inline static NOISE_DATATYPE Fade(NOISE_DATATYPE a_T)
+	{
+		return a_T * a_T * a_T * (a_T * (a_T * 6 - 15) + 10);
+	}
+
+	/** Returns the gradient value based on the hash. */
+	inline static NOISE_DATATYPE Grad(int a_Hash, NOISE_DATATYPE a_X, NOISE_DATATYPE a_Y, NOISE_DATATYPE a_Z)
+	{
+		int hash = a_Hash % 16;
+		NOISE_DATATYPE u = (hash < 8) ? a_X : a_Y;
+		NOISE_DATATYPE v = (hash < 4) ? a_Y : (((hash == 12) || (hash == 14)) ? a_X : a_Z);
+		return (((hash & 1) == 0) ? u : -u) + (((hash & 2) == 0) ? v : -v);
+	}
+};
+
+
+
+
+
 class cPerlinNoise
 {
 public:
@@ -155,7 +212,7 @@ public:
 		NOISE_DATATYPE * a_Array,                        ///< Array to generate into
 		int a_SizeX,                                     ///< Count of the array
 		NOISE_DATATYPE a_StartX, NOISE_DATATYPE a_EndX,  ///< Noise-space coords of the array
-		NOISE_DATATYPE * a_Workspace = nullptr              ///< Workspace that this function can use and trash
+		NOISE_DATATYPE * a_Workspace = nullptr           ///< Workspace that this function can use and trash
 	) const;
 	
 	
@@ -164,7 +221,7 @@ public:
 		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
-		NOISE_DATATYPE * a_Workspace = nullptr              ///< Workspace that this function can use and trash
+		NOISE_DATATYPE * a_Workspace = nullptr           ///< Workspace that this function can use and trash
 	) const;
 	
 	
@@ -174,7 +231,7 @@ public:
 		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
-		NOISE_DATATYPE * a_Workspace = nullptr              ///< Workspace that this function can use and trash
+		NOISE_DATATYPE * a_Workspace = nullptr           ///< Workspace that this function can use and trash
 	) const;
 	
 protected:
@@ -376,8 +433,46 @@ NOISE_DATATYPE cNoise::LinearInterpolate(NOISE_DATATYPE a_A, NOISE_DATATYPE a_B,
 ////////////////////////////////////////////////////////////////////////////////
 // Global functions:
 
-extern void Debug2DNoise(const NOISE_DATATYPE * a_Noise, int a_SizeX, int a_SizeY, const AString & a_FileNameBase);
-extern void Debug3DNoise(const NOISE_DATATYPE * a_Noise, int a_SizeX, int a_SizeY, int a_SizeZ, const AString & a_FileNameBase);
+/** Exports the noise array into a file.
+a_Coeff specifies the value that each array value is multiplied by before being converted into a byte. */
+extern void Debug2DNoise(const NOISE_DATATYPE * a_Array, int a_SizeX, int a_SizeY, const AString & a_FileNameBase, NOISE_DATATYPE a_Coeff = 32);
+
+/** Exports the noise array into a set of files, ordered by XY and XZ.
+a_Coeff specifies the value that each array value is multiplied by before being converted into a byte. */
+extern void Debug3DNoise(const NOISE_DATATYPE * a_Array, int a_SizeX, int a_SizeY, int a_SizeZ, const AString & a_FileNameBase, NOISE_DATATYPE a_Coeff = 32);
+
+
+
+
+/** Linearly interpolates between two values.
+Assumes that a_Ratio is in range [0, 1]. */
+inline NOISE_DATATYPE Lerp(NOISE_DATATYPE a_Val1, NOISE_DATATYPE a_Val2, NOISE_DATATYPE a_Ratio)
+{
+	return a_Val1 + (a_Val2 - a_Val1) * a_Ratio;
+}
+
+
+
+
+
+/** Linearly interpolates between two values, clamping the ratio to [0, 1] first. */
+inline NOISE_DATATYPE ClampedLerp(NOISE_DATATYPE a_Val1, NOISE_DATATYPE a_Val2, NOISE_DATATYPE a_Ratio)
+{
+	if (a_Ratio < 0)
+	{
+		return a_Val1;
+	}
+	if (a_Ratio > 1)
+	{
+		return a_Val2;
+	}
+	return Lerp(a_Val1, a_Val2, a_Ratio);
+}
+
+
+
+
+