X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=src%2Fnoise.cpp;h=255d3faee001c5770f0c864434fb738bc5998720;hb=5f1cd555cd9d1c64426e173b30b5b792d211c835;hp=63682e1e4b3eb4fa87f47dd1f656624764970341;hpb=d9d0efdeedffbef90361886b1f8b0877a4fde1f2;p=minetest.git diff --git a/src/noise.cpp b/src/noise.cpp index 63682e1e4..255d3faee 100644 --- a/src/noise.cpp +++ b/src/noise.cpp @@ -1,192 +1,806 @@ /* -Minetest-c55 -Copyright (C) 2010-2011 celeron55, Perttu Ahola + * Minetest + * Copyright (C) 2010-2014 celeron55, Perttu Ahola + * Copyright (C) 2010-2014 kwolekr, Ryan Kwolek + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without modification, are + * permitted provided that the following conditions are met: + * 1. Redistributions of source code must retain the above copyright notice, this list of + * conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright notice, this list + * of conditions and the following disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND + * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING + * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF + * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ -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 #include "noise.h" #include +#include // memset +#include "debug.h" +#include "util/numeric.h" +#include "util/string.h" +#include "exceptions.h" -#define NOISE_MAGIC_X 1619 -#define NOISE_MAGIC_Y 31337 -#define NOISE_MAGIC_Z 52591 +#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 +typedef float (*Interp2dFxn)( + float v00, float v10, float v01, float v11, + float x, float y); + +typedef float (*Interp3dFxn)( + float v000, float v100, float v010, float v110, + float v001, float v101, float v011, float v111, + float x, float y, float z); + +float cos_lookup[16] = { + 1.0f, 0.9238f, 0.7071f, 0.3826f, .0f, -0.3826f, -0.7071f, -0.9238f, + 1.0f, -0.9238f, -0.7071f, -0.3826f, .0f, 0.3826f, 0.7071f, 0.9238f +}; + +FlagDesc flagdesc_noiseparams[] = { + {"defaults", NOISE_FLAG_DEFAULTS}, + {"eased", NOISE_FLAG_EASED}, + {"absvalue", NOISE_FLAG_ABSVALUE}, + {"pointbuffer", NOISE_FLAG_POINTBUFFER}, + {"simplex", NOISE_FLAG_SIMPLEX}, + {NULL, 0} }; -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 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 +/////////////////////////////////////////////////////////////////////////////// + +PcgRandom::PcgRandom(u64 state, u64 seq) +{ + seed(state, seq); +} + +void PcgRandom::seed(u64 state, u64 seq) +{ + m_state = 0U; + m_inc = (seq << 1u) | 1u; + next(); + m_state += state; + next(); +} + + +u32 PcgRandom::next() +{ + u64 oldstate = m_state; + m_state = oldstate * 6364136223846793005ULL + m_inc; + + u32 xorshifted = ((oldstate >> 18u) ^ oldstate) >> 27u; + u32 rot = oldstate >> 59u; + return (xorshifted >> rot) | (xorshifted << ((-rot) & 31)); +} + + +u32 PcgRandom::range(u32 bound) +{ + // If the bound is 0, we cover the whole RNG's range + if (bound == 0) + return next(); + + /* + This is an optimization of the expression: + 0x100000000ull % bound + since 64-bit modulo operations typically much slower than 32. + */ + u32 threshold = -bound % bound; + u32 r; + + /* + If the bound is not a multiple of the RNG's range, it may cause bias, + e.g. a RNG has a range from 0 to 3 and we take want a number 0 to 2. + Using rand() % 3, the number 0 would be twice as likely to appear. + With a very large RNG range, the effect becomes less prevalent but + still present. + + This can be solved by modifying the range of the RNG to become a + multiple of bound by dropping values above the a threshold. + + In our example, threshold == 4 % 3 == 1, so reject values < 1 + (that is, 0), thus making the range == 3 with no bias. + + This loop may look dangerous, but will always terminate due to the + RNG's property of uniformity. + */ + while ((r = next()) < threshold) + ; + + return r % bound; +} + + +s32 PcgRandom::range(s32 min, s32 max) +{ + if (max < min) + throw PrngException("Invalid range (max < min)"); + + // We have to cast to s64 because otherwise this could overflow, + // and signed overflow is undefined behavior. + u32 bound = (s64)max - (s64)min + 1; + return range(bound) + min; +} + + +void PcgRandom::bytes(void *out, size_t len) +{ + u8 *outb = (u8 *)out; + int bytes_left = 0; + u32 r; + + while (len--) { + if (bytes_left == 0) { + bytes_left = sizeof(u32); + r = next(); + } + + *outb = r & 0xFF; + outb++; + bytes_left--; + r >>= CHAR_BIT; + } +} + + +s32 PcgRandom::randNormalDist(s32 min, s32 max, int num_trials) +{ + s32 accum = 0; + for (int i = 0; i != num_trials; i++) + accum += range(min, max); + return myround((float)accum / num_trials); +} + +/////////////////////////////////////////////////////////////////////////////// + +float noise2d(int x, int y, s32 seed) +{ + unsigned 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; + n = (n >> 13) ^ n; + n = (n * (n * n * 60493 + 19990303) + 1376312589) & 0x7fffffff; + return 1.f - (float)(int)n / 0x40000000; } -double noise3d(int x, int y, int z, int seed) + +float noise3d(int x, int y, int z, s32 seed) { - int n = (NOISE_MAGIC_X * x + NOISE_MAGIC_Y * y + NOISE_MAGIC_Z * z + unsigned 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; + n = (n >> 13) ^ n; + n = (n * (n * n * 60493 + 19990303) + 1376312589) & 0x7fffffff; + return 1.f - (float)(int)n / 0x40000000; +} + + +inline float dotProduct(float vx, float vy, float wx, float wy) +{ + return vx * wx + vy * wy; } -#if 0 -// This is too slow -double noise2d_gradient(double x, double y, int seed) + +inline float linearInterpolation(float v0, float v1, float t) { - // 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) + return v0 + (v1 - v0) * t; +} + + +inline float biLinearInterpolation( + float v00, float v10, + float v01, float v11, + float x, float y) +{ + float tx = easeCurve(x); + float ty = easeCurve(y); + float u = linearInterpolation(v00, v10, tx); + float v = linearInterpolation(v01, v11, tx); + return linearInterpolation(u, v, ty); +} + + +inline float biLinearInterpolationNoEase( + float v00, float v10, + float v01, float v11, + float x, float y) +{ + float u = linearInterpolation(v00, v10, x); + float v = linearInterpolation(v01, v11, x); + return linearInterpolation(u, v, y); +} + + +float triLinearInterpolation( + float v000, float v100, float v010, float v110, + float v001, float v101, float v011, float v111, + float x, float y, float z) +{ + float tx = easeCurve(x); + float ty = easeCurve(y); + float tz = easeCurve(z); + float u = biLinearInterpolationNoEase(v000, v100, v010, v110, tx, ty); + float v = biLinearInterpolationNoEase(v001, v101, v011, v111, tx, ty); + return linearInterpolation(u, v, tz); +} + +float triLinearInterpolationNoEase( + float v000, float v100, float v010, float v110, + float v001, float v101, float v011, float v111, + float x, float y, float z) +{ + float u = biLinearInterpolationNoEase(v000, v100, v010, v110, x, y); + float v = biLinearInterpolationNoEase(v001, v101, v011, v111, x, y); + return linearInterpolation(u, v, z); +} + +float noise2d_gradient(float x, float y, s32 seed, bool eased) { // 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 x0 = myfloor(x); + int y0 = myfloor(y); // 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); + float xl = x - (float)x0; + float yl = y - (float)y0; + // Get values for corners of square + float v00 = noise2d(x0, y0, seed); + float v10 = noise2d(x0+1, y0, seed); + float v01 = noise2d(x0, y0+1, seed); + float v11 = noise2d(x0+1, y0+1, seed); // Interpolate - return biLinearInterpolation(v00,v10,v01,v11,xl,yl); + if (eased) + return biLinearInterpolation(v00, v10, v01, v11, xl, yl); + + return biLinearInterpolationNoEase(v00, v10, v01, v11, xl, yl); } -#endif -double noise3d_gradient(double x, double y, double z, int seed) + +float noise3d_gradient(float x, float y, float z, s32 seed, bool eased) { // 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); + int x0 = myfloor(x); + int y0 = myfloor(y); + int z0 = myfloor(z); // Calculate the remaining part of the coordinates - double xl = x - (double)x0; - double yl = y - (double)y0; - double zl = z - (double)z0; + float xl = x - (float)x0; + float yl = y - (float)y0; + float zl = z - (float)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); + float v000 = noise3d(x0, y0, z0, seed); + float v100 = noise3d(x0 + 1, y0, z0, seed); + float v010 = noise3d(x0, y0 + 1, z0, seed); + float v110 = noise3d(x0 + 1, y0 + 1, z0, seed); + float v001 = noise3d(x0, y0, z0 + 1, seed); + float v101 = noise3d(x0 + 1, y0, z0 + 1, seed); + float v011 = noise3d(x0, y0 + 1, z0 + 1, seed); + float v111 = noise3d(x0 + 1, y0 + 1, z0 + 1, seed); // Interpolate - return triLinearInterpolation(v000,v100,v010,v110,v001,v101,v011,v111,xl,yl,zl); + if (eased) { + return triLinearInterpolation( + v000, v100, v010, v110, + v001, v101, v011, v111, + xl, yl, zl); + } + + return triLinearInterpolationNoEase( + v000, v100, v010, v110, + v001, v101, v011, v111, + xl, yl, zl); } -double noise2d_perlin(double x, double y, int seed, - int octaves, double persistence) + +float noise2d_perlin(float x, float y, s32 seed, + int octaves, float persistence, bool eased) { - double a = 0; - double f = 1.0; - double g = 1.0; - for(int i=0; i= 1.0) + return 0.0; + return (1.0 - v); +} + + +///////////////////////// [ New noise ] //////////////////////////// + + +float NoisePerlin2D(NoiseParams *np, float x, float y, s32 seed) +{ + float a = 0; + float f = 1.0; + float g = 1.0; + + x /= np->spread.X; + y /= np->spread.Y; + seed += np->seed; + + for (size_t i = 0; i < np->octaves; i++) { + float noiseval = noise2d_gradient(x * f, y * f, seed + i, + np->flags & (NOISE_FLAG_DEFAULTS | NOISE_FLAG_EASED)); + + if (np->flags & NOISE_FLAG_ABSVALUE) + noiseval = std::fabs(noiseval); + + a += g * noiseval; + f *= np->lacunarity; + g *= np->persist; + } + + return np->offset + a * np->scale; +} + + +float NoisePerlin3D(NoiseParams *np, float x, float y, float z, s32 seed) +{ + float a = 0; + float f = 1.0; + float g = 1.0; + + x /= np->spread.X; + y /= np->spread.Y; + z /= np->spread.Z; + seed += np->seed; + + for (size_t i = 0; i < np->octaves; i++) { + float noiseval = noise3d_gradient(x * f, y * f, z * f, seed + i, + np->flags & NOISE_FLAG_EASED); + + if (np->flags & NOISE_FLAG_ABSVALUE) + noiseval = std::fabs(noiseval); + + a += g * noiseval; + f *= np->lacunarity; + g *= np->persist; + } + + return np->offset + a * np->scale; +} + + +Noise::Noise(NoiseParams *np_, s32 seed, u32 sx, u32 sy, u32 sz) +{ + memcpy(&np, np_, sizeof(np)); + this->seed = seed; + this->sx = sx; + this->sy = sy; + this->sz = sz; + + allocBuffers(); +} + + +Noise::~Noise() +{ + delete[] gradient_buf; + delete[] persist_buf; + delete[] noise_buf; + delete[] result; +} + + +void Noise::allocBuffers() +{ + if (sx < 1) + sx = 1; + if (sy < 1) + sy = 1; + if (sz < 1) + sz = 1; + + this->noise_buf = NULL; + resizeNoiseBuf(sz > 1); + + delete[] gradient_buf; + delete[] persist_buf; + delete[] result; + + try { + size_t bufsize = sx * sy * sz; + this->persist_buf = NULL; + this->gradient_buf = new float[bufsize]; + this->result = new float[bufsize]; + } catch (std::bad_alloc &e) { + throw InvalidNoiseParamsException(); + } +} + + +void Noise::setSize(u32 sx, u32 sy, u32 sz) +{ + this->sx = sx; + this->sy = sy; + this->sz = sz; + + allocBuffers(); +} + + +void Noise::setSpreadFactor(v3f spread) +{ + this->np.spread = spread; + + resizeNoiseBuf(sz > 1); +} + + +void Noise::setOctaves(int octaves) +{ + this->np.octaves = octaves; + + resizeNoiseBuf(sz > 1); +} + + +void Noise::resizeNoiseBuf(bool is3d) +{ + //maximum possible spread value factor + float ofactor = (np.lacunarity > 1.0) ? + pow(np.lacunarity, np.octaves - 1) : + np.lacunarity; + + // noise lattice point count + // (int)(sz * spread * ofactor) is # of lattice points crossed due to length + float num_noise_points_x = sx * ofactor / np.spread.X; + float num_noise_points_y = sy * ofactor / np.spread.Y; + float num_noise_points_z = sz * ofactor / np.spread.Z; + + // protect against obviously invalid parameters + if (num_noise_points_x > 1000000000.f || + num_noise_points_y > 1000000000.f || + num_noise_points_z > 1000000000.f) + throw InvalidNoiseParamsException(); + + // + 2 for the two initial endpoints + // + 1 for potentially crossing a boundary due to offset + size_t nlx = (size_t)std::ceil(num_noise_points_x) + 3; + size_t nly = (size_t)std::ceil(num_noise_points_y) + 3; + size_t nlz = is3d ? (size_t)std::ceil(num_noise_points_z) + 3 : 1; + + delete[] noise_buf; + try { + noise_buf = new float[nlx * nly * nlz]; + } catch (std::bad_alloc &e) { + throw InvalidNoiseParamsException(); + } +} + + +/* + * NB: This algorithm is not optimal in terms of space complexity. The entire + * integer lattice of noise points could be done as 2 lines instead, and for 3D, + * 2 lines + 2 planes. + * However, this would require the noise calls to be interposed with the + * interpolation loops, which may trash the icache, leading to lower overall + * performance. + * Another optimization that could save half as many noise calls is to carry over + * values from the previous noise lattice as midpoints in the new lattice for the + * next octave. + */ +#define idx(x, y) ((y) * nlx + (x)) +void Noise::gradientMap2D( + float x, float y, + float step_x, float step_y, + s32 seed) +{ + float v00, v01, v10, v11, u, v, orig_u; + u32 index, i, j, noisex, noisey; + u32 nlx, nly; + s32 x0, y0; + + bool eased = np.flags & (NOISE_FLAG_DEFAULTS | NOISE_FLAG_EASED); + Interp2dFxn interpolate = eased ? + biLinearInterpolation : biLinearInterpolationNoEase; + + x0 = std::floor(x); + y0 = std::floor(y); + u = x - (float)x0; + v = y - (float)y0; + orig_u = u; + + //calculate noise point lattice + nlx = (u32)(u + sx * step_x) + 2; + nly = (u32)(v + sy * step_y) + 2; + index = 0; + for (j = 0; j != nly; j++) + for (i = 0; i != nlx; i++) + noise_buf[index++] = noise2d(x0 + i, y0 + j, seed); + + //calculate interpolations + index = 0; + noisey = 0; + for (j = 0; j != sy; j++) { + v00 = noise_buf[idx(0, noisey)]; + v10 = noise_buf[idx(1, noisey)]; + v01 = noise_buf[idx(0, noisey + 1)]; + v11 = noise_buf[idx(1, noisey + 1)]; + + u = orig_u; + noisex = 0; + for (i = 0; i != sx; i++) { + gradient_buf[index++] = interpolate(v00, v10, v01, v11, u, v); + + u += step_x; + if (u >= 1.0) { + u -= 1.0; + noisex++; + v00 = v10; + v01 = v11; + v10 = noise_buf[idx(noisex + 1, noisey)]; + v11 = noise_buf[idx(noisex + 1, noisey + 1)]; + } + } + + v += step_y; + if (v >= 1.0) { + v -= 1.0; + noisey++; + } + } +} +#undef idx + + +#define idx(x, y, z) ((z) * nly * nlx + (y) * nlx + (x)) +void Noise::gradientMap3D( + float x, float y, float z, + float step_x, float step_y, float step_z, + s32 seed) +{ + float v000, v010, v100, v110; + float v001, v011, v101, v111; + float u, v, w, orig_u, orig_v; + u32 index, i, j, k, noisex, noisey, noisez; + u32 nlx, nly, nlz; + s32 x0, y0, z0; + + Interp3dFxn interpolate = (np.flags & NOISE_FLAG_EASED) ? + triLinearInterpolation : triLinearInterpolationNoEase; + + x0 = std::floor(x); + y0 = std::floor(y); + z0 = std::floor(z); + u = x - (float)x0; + v = y - (float)y0; + w = z - (float)z0; + orig_u = u; + orig_v = v; + + //calculate noise point lattice + nlx = (u32)(u + sx * step_x) + 2; + nly = (u32)(v + sy * step_y) + 2; + nlz = (u32)(w + sz * step_z) + 2; + index = 0; + for (k = 0; k != nlz; k++) + for (j = 0; j != nly; j++) + for (i = 0; i != nlx; i++) + noise_buf[index++] = noise3d(x0 + i, y0 + j, z0 + k, seed); + + //calculate interpolations + index = 0; + noisey = 0; + noisez = 0; + for (k = 0; k != sz; k++) { + v = orig_v; + noisey = 0; + for (j = 0; j != sy; j++) { + v000 = noise_buf[idx(0, noisey, noisez)]; + v100 = noise_buf[idx(1, noisey, noisez)]; + v010 = noise_buf[idx(0, noisey + 1, noisez)]; + v110 = noise_buf[idx(1, noisey + 1, noisez)]; + v001 = noise_buf[idx(0, noisey, noisez + 1)]; + v101 = noise_buf[idx(1, noisey, noisez + 1)]; + v011 = noise_buf[idx(0, noisey + 1, noisez + 1)]; + v111 = noise_buf[idx(1, noisey + 1, noisez + 1)]; + + u = orig_u; + noisex = 0; + for (i = 0; i != sx; i++) { + gradient_buf[index++] = interpolate( + v000, v100, v010, v110, + v001, v101, v011, v111, + u, v, w); + + u += step_x; + if (u >= 1.0) { + u -= 1.0; + noisex++; + v000 = v100; + v010 = v110; + v100 = noise_buf[idx(noisex + 1, noisey, noisez)]; + v110 = noise_buf[idx(noisex + 1, noisey + 1, noisez)]; + v001 = v101; + v011 = v111; + v101 = noise_buf[idx(noisex + 1, noisey, noisez + 1)]; + v111 = noise_buf[idx(noisex + 1, noisey + 1, noisez + 1)]; + } + } + + v += step_y; + if (v >= 1.0) { + v -= 1.0; + noisey++; + } + } + + w += step_z; + if (w >= 1.0) { + w -= 1.0; + noisez++; + } + } +} +#undef idx + + +float *Noise::perlinMap2D(float x, float y, float *persistence_map) +{ + float f = 1.0, g = 1.0; + size_t bufsize = sx * sy; + + x /= np.spread.X; + y /= np.spread.Y; + + memset(result, 0, sizeof(float) * bufsize); + + if (persistence_map) { + if (!persist_buf) + persist_buf = new float[bufsize]; + for (size_t i = 0; i != bufsize; i++) + persist_buf[i] = 1.0; + } + + for (size_t oct = 0; oct < np.octaves; oct++) { + gradientMap2D(x * f, y * f, + f / np.spread.X, f / np.spread.Y, + seed + np.seed + oct); + + updateResults(g, persist_buf, persistence_map, bufsize); + + f *= np.lacunarity; + g *= np.persist; + } + + if (std::fabs(np.offset - 0.f) > 0.00001 || std::fabs(np.scale - 1.f) > 0.00001) { + for (size_t i = 0; i != bufsize; i++) + result[i] = result[i] * np.scale + np.offset; + } + + return result; +} + + +float *Noise::perlinMap3D(float x, float y, float z, float *persistence_map) +{ + float f = 1.0, g = 1.0; + size_t bufsize = sx * sy * sz; + + x /= np.spread.X; + y /= np.spread.Y; + z /= np.spread.Z; + + memset(result, 0, sizeof(float) * bufsize); + + if (persistence_map) { + if (!persist_buf) + persist_buf = new float[bufsize]; + for (size_t i = 0; i != bufsize; i++) + persist_buf[i] = 1.0; + } + + for (size_t oct = 0; oct < np.octaves; oct++) { + gradientMap3D(x * f, y * f, z * f, + f / np.spread.X, f / np.spread.Y, f / np.spread.Z, + seed + np.seed + oct); + + updateResults(g, persist_buf, persistence_map, bufsize); + + f *= np.lacunarity; + g *= np.persist; + } + + if (std::fabs(np.offset - 0.f) > 0.00001 || std::fabs(np.scale - 1.f) > 0.00001) { + for (size_t i = 0; i != bufsize; i++) + result[i] = result[i] * np.scale + np.offset; + } + + return result; +} + + +void Noise::updateResults(float g, float *gmap, + const float *persistence_map, size_t bufsize) +{ + // This looks very ugly, but it is 50-70% faster than having + // conditional statements inside the loop + if (np.flags & NOISE_FLAG_ABSVALUE) { + if (persistence_map) { + for (size_t i = 0; i != bufsize; i++) { + result[i] += gmap[i] * std::fabs(gradient_buf[i]); + gmap[i] *= persistence_map[i]; + } + } else { + for (size_t i = 0; i != bufsize; i++) + result[i] += g * std::fabs(gradient_buf[i]); + } + } else { + if (persistence_map) { + for (size_t i = 0; i != bufsize; i++) { + result[i] += gmap[i] * gradient_buf[i]; + gmap[i] *= persistence_map[i]; + } + } else { + for (size_t i = 0; i != bufsize; i++) + result[i] += g * gradient_buf[i]; + } + } +}