random.cc

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// Copyright (c) 2018, ETH Zurich and UNC Chapel Hill.
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// Author: Johannes L. Schoenberger (jsch-at-demuc-dot-de)
 
#include "util/random.h"
 
#include <mutex>
 
namespace colmap {
 
thread_local std::unique_ptr<std::mt19937> PRNG;
 
void SetPRNGSeed(unsigned seed) {
    PRNG = std::make_unique<std::mt19937>(seed);
    // srand is not thread-safe.
    static std::mutex mutex;
    std::unique_lock<std::mutex> lock(mutex);
    srand(seed);
}
 
}  // namespace colmap