diff options
Diffstat (limited to 'src/Noise.h')
| -rw-r--r-- | src/Noise.h | 105 |
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); +} + + + + + |