From: Perttu Ahola Date: Thu, 19 May 2011 17:06:54 +0000 (+0300) Subject: Add (possibly non-compatible) work-in-progress noise.{h,cpp} so that they won't be... X-Git-Url: http://81.2.79.47:8989/gitweb/?a=commitdiff_plain;h=bc6d477cbb66527da7c4976856f28a3d67d3dff9;p=zefram%2Fminetest%2Fminetest_engine.git Add (possibly non-compatible) work-in-progress noise.{h,cpp} so that they won't be accidentally lost. These are useful for upcoming mapgen updates. --- diff --git a/src/noise.cpp.new b/src/noise.cpp.new new file mode 100644 index 00000000..e7923dae --- /dev/null +++ b/src/noise.cpp.new @@ -0,0 +1,410 @@ +/* +Minetest-c55 +Copyright (C) 2010-2011 celeron55, Perttu Ahola + +This program is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2 of the License, or +(at your option) any later version. + +This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License along +with this program; if not, write to the Free Software Foundation, Inc., +51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. +*/ + +#include +#include "noise.h" +#include +#include "debug.h" + +#define NOISE_MAGIC_X 1619 +#define NOISE_MAGIC_Y 31337 +#define NOISE_MAGIC_Z 52591 +#define NOISE_MAGIC_SEED 1013 + +double cos_lookup[16] = { + 1.0,0.9238,0.7071,0.3826,0,-0.3826,-0.7071,-0.9238, + 1.0,-0.9238,-0.7071,-0.3826,0,0.3826,0.7071,0.9238 +}; + +double dotProduct(double vx, double vy, double wx, double wy){ + return vx*wx+vy*wy; +} + +double easeCurve(double t){ + return 6*pow(t,5)-15*pow(t,4)+10*pow(t,3); +} + +double linearInterpolation(double x0, double x1, double t){ + return x0+(x1-x0)*t; +} + +double biLinearInterpolation(double x0y0, double x1y0, double x0y1, double x1y1, double x, double y){ + double tx = easeCurve(x); + double ty = easeCurve(y); + /*double tx = x; + double ty = y;*/ + double u = linearInterpolation(x0y0,x1y0,tx); + double v = linearInterpolation(x0y1,x1y1,tx); + return linearInterpolation(u,v,ty); +} + +double triLinearInterpolation( + double v000, double v100, double v010, double v110, + double v001, double v101, double v011, double v111, + double x, double y, double z) +{ + /*double tx = easeCurve(x); + double ty = easeCurve(y); + double tz = easeCurve(z);*/ + double tx = x; + double ty = y; + double tz = z; + return( + v000*(1-tx)*(1-ty)*(1-tz) + + v100*tx*(1-ty)*(1-tz) + + v010*(1-tx)*ty*(1-tz) + + v110*tx*ty*(1-tz) + + v001*(1-tx)*(1-ty)*tz + + v101*tx*(1-ty)*tz + + v011*(1-tx)*ty*tz + + v111*tx*ty*tz + ); +} + +double noise2d(int x, int y, int seed) +{ + int n = (NOISE_MAGIC_X * x + NOISE_MAGIC_Y * y + + NOISE_MAGIC_SEED * seed) & 0x7fffffff; + n = (n>>13)^n; + n = (n * (n*n*60493+19990303) + 1376312589) & 0x7fffffff; + return 1.0 - (double)n/1073741824; +} + +double noise3d(int x, int y, int z, int seed) +{ + int n = (NOISE_MAGIC_X * x + NOISE_MAGIC_Y * y + NOISE_MAGIC_Z * z + + NOISE_MAGIC_SEED * seed) & 0x7fffffff; + n = (n>>13)^n; + n = (n * (n*n*60493+19990303) + 1376312589) & 0x7fffffff; + return 1.0 - (double)n/1073741824; +} + +#if 0 +double noise2d_gradient(double x, double y, int seed) +{ + // Calculate the integer coordinates + int x0 = (x > 0.0 ? (int)x : (int)x - 1); + int y0 = (y > 0.0 ? (int)y : (int)y - 1); + // Calculate the remaining part of the coordinates + double xl = x - (double)x0; + double yl = y - (double)y0; + // Calculate random cosine lookup table indices for the integer corners. + // They are looked up as unit vector gradients from the lookup table. + int n00 = (int)((noise2d(x0, y0, seed)+1)*8); + int n10 = (int)((noise2d(x0+1, y0, seed)+1)*8); + int n01 = (int)((noise2d(x0, y0+1, seed)+1)*8); + int n11 = (int)((noise2d(x0+1, y0+1, seed)+1)*8); + // Make a dot product for the gradients and the positions, to get the values + double s = dotProduct(cos_lookup[n00], cos_lookup[(n00+12)%16], xl, yl); + double u = dotProduct(-cos_lookup[n10], cos_lookup[(n10+12)%16], 1.-xl, yl); + double v = dotProduct(cos_lookup[n01], -cos_lookup[(n01+12)%16], xl, 1.-yl); + double w = dotProduct(-cos_lookup[n11], -cos_lookup[(n11+12)%16], 1.-xl, 1.-yl); + // Interpolate between the values + return biLinearInterpolation(s,u,v,w,xl,yl); +} +#endif + +#if 1 +double noise2d_gradient(double x, double y, int seed) +{ + // Calculate the integer coordinates + int x0 = (x > 0.0 ? (int)x : (int)x - 1); + int y0 = (y > 0.0 ? (int)y : (int)y - 1); + // Calculate the remaining part of the coordinates + double xl = x - (double)x0; + double yl = y - (double)y0; + // Get values for corners of cube + double v00 = noise2d(x0, y0, seed); + double v10 = noise2d(x0+1, y0, seed); + double v01 = noise2d(x0, y0+1, seed); + double v11 = noise2d(x0+1, y0+1, seed); + // Interpolate + return biLinearInterpolation(v00,v10,v01,v11,xl,yl); +} +#endif + +double noise3d_gradient(double x, double y, double z, int seed) +{ + // Calculate the integer coordinates + int x0 = (x > 0.0 ? (int)x : (int)x - 1); + int y0 = (y > 0.0 ? (int)y : (int)y - 1); + int z0 = (z > 0.0 ? (int)z : (int)z - 1); + // Calculate the remaining part of the coordinates + double xl = x - (double)x0; + double yl = y - (double)y0; + double zl = z - (double)z0; + // Get values for corners of cube + double v000 = noise3d(x0, y0, z0, seed); + double v100 = noise3d(x0+1, y0, z0, seed); + double v010 = noise3d(x0, y0+1, z0, seed); + double v110 = noise3d(x0+1, y0+1, z0, seed); + double v001 = noise3d(x0, y0, z0+1, seed); + double v101 = noise3d(x0+1, y0, z0+1, seed); + double v011 = noise3d(x0, y0+1, z0+1, seed); + double v111 = noise3d(x0+1, y0+1, z0+1, seed); + // Interpolate + return triLinearInterpolation(v000,v100,v010,v110,v001,v101,v011,v111,xl,yl,zl); +} + +double noise2d_perlin(double x, double y, int seed, + int octaves, double persistence) +{ + double a = 0; + double f = 1.0; + double g = 1.0; + for(int i=0; i0, 0->1, 1->0 +double contour(double v) +{ + v = fabs(v); + if(v >= 1.0) + return 0.0; + return (1.0-v); +} + +double noise3d_param(const NoiseParams ¶m, double x, double y, double z) +{ + double s = param.pos_scale; + x /= s; + y /= s; + z /= s; + + if(param.type == NOISE_PERLIN) + { + return param.noise_scale*noise3d_perlin(x,y,z, param.seed, + param.octaves, + param.persistence); + } + else if(param.type == NOISE_PERLIN_ABS) + { + return param.noise_scale*noise3d_perlin_abs(x,y,z, param.seed, + param.octaves, + param.persistence); + } + else if(param.type == NOISE_PERLIN_CONTOUR) + { + return contour(param.noise_scale*noise3d_perlin(x,y,z, + param.seed, param.octaves, + param.persistence)); + } + else if(param.type == NOISE_PERLIN_CONTOUR_FLIP_YZ) + { + return contour(param.noise_scale*noise3d_perlin(x,z,y, + param.seed, param.octaves, + param.persistence)); + } + else assert(0); +} + +/* + NoiseBuffer +*/ + +NoiseBuffer::NoiseBuffer(): + m_data(NULL) +{ +} + +NoiseBuffer::~NoiseBuffer() +{ + clear(); +} + +void NoiseBuffer::clear() +{ + if(m_data) + delete[] m_data; + m_data = NULL; + m_size_x = 0; + m_size_y = 0; + m_size_z = 0; +} + +void NoiseBuffer::create(const NoiseParams ¶m, + double first_x, double first_y, double first_z, + double last_x, double last_y, double last_z, + double samplelength_x, double samplelength_y, double samplelength_z) +{ + clear(); + + m_start_x = first_x - samplelength_x; + m_start_y = first_y - samplelength_y; + m_start_z = first_z - samplelength_z; + m_samplelength_x = samplelength_x; + m_samplelength_y = samplelength_y; + m_samplelength_z = samplelength_z; + + m_size_x = (last_x - m_start_x)/samplelength_x + 2; + m_size_y = (last_y - m_start_y)/samplelength_y + 2; + m_size_z = (last_z - m_start_z)/samplelength_z + 2; + + m_data = new double[m_size_x*m_size_y*m_size_z]; + + for(int x=0; x= 0); + assert(i < m_size_x*m_size_y*m_size_z); + m_data[i] = d; +} + +void NoiseBuffer::intMultiply(int x, int y, int z, double d) +{ + int i = m_size_x*m_size_y*z + m_size_x*y + x; + assert(i >= 0); + assert(i < m_size_x*m_size_y*m_size_z); + m_data[i] = m_data[i] * d; +} + +double NoiseBuffer::intGet(int x, int y, int z) +{ + int i = m_size_x*m_size_y*z + m_size_x*y + x; + assert(i >= 0); + assert(i < m_size_x*m_size_y*m_size_z); + return m_data[i]; +} + +double NoiseBuffer::get(double x, double y, double z) +{ + x -= m_start_x; + y -= m_start_y; + z -= m_start_z; + x /= m_samplelength_x; + y /= m_samplelength_y; + z /= m_samplelength_z; + // Calculate the integer coordinates + int x0 = (x > 0.0 ? (int)x : (int)x - 1); + int y0 = (y > 0.0 ? (int)y : (int)y - 1); + int z0 = (z > 0.0 ? (int)z : (int)z - 1); + // Calculate the remaining part of the coordinates + double xl = x - (double)x0; + double yl = y - (double)y0; + double zl = z - (double)z0; + // Get values for corners of cube + double v000 = intGet(x0, y0, z0); + double v100 = intGet(x0+1, y0, z0); + double v010 = intGet(x0, y0+1, z0); + double v110 = intGet(x0+1, y0+1, z0); + double v001 = intGet(x0, y0, z0+1); + double v101 = intGet(x0+1, y0, z0+1); + double v011 = intGet(x0, y0+1, z0+1); + double v111 = intGet(x0+1, y0+1, z0+1); + // Interpolate + return triLinearInterpolation(v000,v100,v010,v110,v001,v101,v011,v111,xl,yl,zl); +} + diff --git a/src/noise.h.new b/src/noise.h.new new file mode 100644 index 00000000..59ca1bf9 --- /dev/null +++ b/src/noise.h.new @@ -0,0 +1,108 @@ +/* +Minetest-c55 +Copyright (C) 2010-2011 celeron55, Perttu Ahola + +This program is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 2 of the License, or +(at your option) any later version. + +This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License along +with this program; if not, write to the Free Software Foundation, Inc., +51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. +*/ + +#ifndef NOISE_HEADER +#define NOISE_HEADER + +double easeCurve(double t); + +// Return value: -1 ... 1 +double noise2d(int x, int y, int seed); +double noise3d(int x, int y, int z, int seed); + +double noise2d_gradient(double x, double y, int seed); +double noise3d_gradient(double x, double y, double z, int seed); + +double noise2d_perlin(double x, double y, int seed, + int octaves, double persistence); + +double noise2d_perlin_abs(double x, double y, int seed, + int octaves, double persistence); + +double noise3d_perlin(double x, double y, double z, int seed, + int octaves, double persistence); + +double noise3d_perlin_abs(double x, double y, double z, int seed, + int octaves, double persistence); + +enum NoiseType +{ + NOISE_PERLIN, + NOISE_PERLIN_ABS, + NOISE_PERLIN_CONTOUR, + NOISE_PERLIN_CONTOUR_FLIP_YZ +}; + +struct NoiseParams +{ + NoiseType type; + int seed; + int octaves; + double persistence; + double pos_scale; + double noise_scale; // Useful for contour noises + + NoiseParams(NoiseType type_=NOISE_PERLIN, int seed_=0, + int octaves_=3, double persistence_=0.5, + double pos_scale_=100.0, double noise_scale_=1.0): + type(type_), + seed(seed_), + octaves(octaves_), + persistence(persistence_), + pos_scale(pos_scale_), + noise_scale(noise_scale_) + { + } +}; + +double noise3d_param(const NoiseParams ¶m, double x, double y, double z); + +class NoiseBuffer +{ +public: + NoiseBuffer(); + ~NoiseBuffer(); + + void clear(); + void create(const NoiseParams ¶m, + double first_x, double first_y, double first_z, + double last_x, double last_y, double last_z, + double samplelength_x, double samplelength_y, double samplelength_z); + void multiply(const NoiseParams ¶m); + // Deprecated + void create(int seed, int octaves, double persistence, + bool abs, + double first_x, double first_y, double first_z, + double last_x, double last_y, double last_z, + double samplelength_x, double samplelength_y, double samplelength_z); + + void intSet(int x, int y, int z, double d); + void intMultiply(int x, int y, int z, double d); + double intGet(int x, int y, int z); + double get(double x, double y, double z); + +private: + double *m_data; + double m_start_x, m_start_y, m_start_z; + double m_samplelength_x, m_samplelength_y, m_samplelength_z; + int m_size_x, m_size_y, m_size_z; +}; + +#endif +