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#include "random.hpp"
#include <random>
#include <limits>
namespace floormat {
static thread_local auto g = std::independent_bits_engine<decltype(std::ranlux48{}), 32, uint32_t>{std::ranlux48{}};
random_engine::~random_engine() = default;
struct random_engine_impl final : random_engine {
size_t operator()() override;
float operator()(float min, float max) override;
};
size_t random_engine_impl::operator()()
{
if constexpr(sizeof(size_t) > sizeof(uint32_t))
{
constexpr auto N = (sizeof(size_t) + sizeof(uint32_t)-1) / sizeof(uint32_t);
static_assert(N >= 1);
union {
size_t x;
uint32_t a[N];
} ret;
for (auto i = 0uz; i < N; i++)
ret.a[i] = g();
return ret.x;
}
else
return (size_t)g();
}
float random_engine_impl::operator()(float min, float max)
{
std::uniform_real_distribution<float> dist{min, max};
return dist(g);
}
static random_engine& make_random_impl() {
static random_engine_impl ret;
return ret;
}
random_engine& random = make_random_impl();
} // namespace floormat
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