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/* |
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* This file is part of Deliantra, the Roguelike Realtime MMORPG. |
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* |
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* Copyright (©) 2010,2011 Marc Alexander Lehmann / Robin Redeker / the Deliantra team |
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* |
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* Deliantra is free software: you can redistribute it and/or modify it under |
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* the terms of the Affero GNU General Public License as published by the |
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* Free Software Foundation, either version 3 of the License, or (at your |
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* option) any later version. |
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* |
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* This program is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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* GNU General Public License for more details. |
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* |
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* You should have received a copy of the Affero GNU General Public License |
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* and the GNU General Public License along with this program. If not, see |
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* <http://www.gnu.org/licenses/>. |
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* |
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* The authors can be reached via e-mail to <support@deliantra.net> |
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*/ |
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|
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#ifndef NOISE_H_ |
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#define NOISE_H_ |
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|
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#include <blitz/tinyvec.h> |
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#include <blitz/tinyvec-et.h> |
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|
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#include "global.h" |
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|
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typedef blitz::TinyVector<float,2> vec2d; |
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typedef blitz::TinyVector<float,3> vec3d; |
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|
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///////////////////////////////////////////////////////////////////////////// |
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|
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template<int N, typename T = uint8_t> |
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struct permutation |
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{ |
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T pmap[N]; |
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|
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template<class generator> |
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void seed (generator &rng) |
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{ |
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for (int i = 0; i < N; ++i) |
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pmap[i] = i; |
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|
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// fisher-yates to randomly perturb |
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for (int i = N; --i; ) |
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::swap (pmap[i], pmap[rng (i + 1)]); |
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} |
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|
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T operator ()(T v) |
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{ |
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return pmap[v & (N - 1)]; |
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} |
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}; |
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|
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template<class vec_t> |
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struct noise_gen; |
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|
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// modelled after 2d/3d kensler noise without projection |
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template<> |
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struct noise_gen<vec2d> |
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{ |
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permutation<256, uint8_t> rvmap[2]; |
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vec2d rvec[256]; // random unit vectors |
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|
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noise_gen<vec2d> (uint32_t seed); |
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vec2d::T_numtype operator() (vec2d P); |
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}; |
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|
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template<> |
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struct noise_gen<vec3d> |
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{ |
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permutation<256, uint8_t> rvmap[3]; |
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|
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noise_gen<vec3d> (uint32_t seed); |
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vec2d::T_numtype operator() (vec3d P); |
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|
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// noise projected on a surface with normal n |
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vec2d::T_numtype operator() (vec3d P, vec3d N); |
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}; |
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|
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template<class vec_t, int a, int b> |
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struct rotate_nn |
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{ |
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typename vec_t::T_numtype s, c; |
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|
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void set (typename vec_t::T_numtype angle) |
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{ |
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s = sin (angle); |
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c = cos (angle); |
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} |
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|
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void operator ()(vec_t &P) const |
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{ |
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vec_t o = P; |
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|
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P[a] = o[a] * c - o[b] * s; |
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P[b] = o[a] * s + o[b] * c; |
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} |
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}; |
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|
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template<class vec_t> |
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struct rotate_xy : rotate_nn<vec_t, 0, 1> |
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{ |
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}; |
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|
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template<class vec_t> |
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struct rotate_xz : rotate_nn<vec_t, 0, 2> |
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{ |
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}; |
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|
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template<class vec_t> |
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struct rotate_yz : rotate_nn<vec_t, 1, 2> |
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{ |
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}; |
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|
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template<class vec_t> |
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struct frac_gen |
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: noise_gen<vec_t> |
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{ |
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enum { MAX_OCTAVES = 64 }; |
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|
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typedef typename vec_t::T_numtype value_t; |
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|
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value_t h, lac, ex[MAX_OCTAVES]; |
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value_t fbm_mul[MAX_OCTAVES]; |
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rotate_xy<vec_t> rot[MAX_OCTAVES]; |
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|
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value_t noise (vec_t P) |
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{ |
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return operator() (P); |
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} |
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|
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frac_gen (value_t hurst_expo = .5f, value_t lacunarity = 2.f); |
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|
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value_t fBm (vec_t P, int octaves); |
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value_t turbulence (vec_t P, int octaves); |
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value_t multifractal (vec_t P, int octaves, value_t offset = 1); |
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value_t heterofractal (vec_t P, int octaves, value_t offset = 1); |
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value_t hybridfractal (vec_t P, int octaves, value_t offset = 1, value_t gain = 1); |
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value_t terrain (vec_t P, int octaves); |
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value_t terrain2 (vec_t P, int octaves); |
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value_t ridgedmultifractal (vec_t P, int octaves, value_t offset = 1, value_t gain = 8); |
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}; |
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|
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#endif |
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|
