forked from bartvdbraak/blender
f82f1513e0
SCons is currently broken on my laptop, so can't test if it works for sure, so please do tests of that.
62 lines
1.1 KiB
C++
62 lines
1.1 KiB
C++
#include <cassert>
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#include <cmath>
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#include <vector>
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namespace boost {
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#if __cplusplus > 199711L
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# include <random>
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typedef std::mt19937 mt19937;
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#else
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# include <stdlib.h>
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struct mt19937 {
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int operator()() {
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return rand();
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}
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int max() {
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return RAND_MAX;
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}
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};
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#endif
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template<typename T>
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struct uniform_on_sphere {
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typedef std::vector<T> result_type;
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uniform_on_sphere(int dimension) {
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assert(dimension == 3);
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}
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std::vector<T>
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operator()(float u1, float u2) {
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T z = 1.0 - 2.0*u1;
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T r = std::sqrt(std::max(0.0, 1.0 - z*z));
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T phi = 2.0*M_PI*u2;
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T x = r*std::cos(phi);
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T y = r*std::sin(phi);
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std::vector<T> result;
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result.push_back(x);
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result.push_back(y);
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result.push_back(z);
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return result;
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}
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};
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template<typename RNG, typename DISTR>
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struct variate_generator {
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variate_generator(RNG rng, DISTR distr)
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: rng_(rng), distr_(distr) {}
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typename DISTR::result_type
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operator()() {
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float rng_max_inv = 1.0 / rng_.max();
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return distr_(rng_() * rng_max_inv, rng_() * rng_max_inv);
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}
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RNG rng_;
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DISTR distr_;
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};
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}
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