Gary Talent
8559ab53cc
git-subtree-dir: deps/ox git-subtree-split: c63e0c1d72f30cfb7b3076c69744b0f53d4d79b1
41 lines
806 B
C++
41 lines
806 B
C++
/*
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* Copyright 2015 - 2017 gtalent2@gmail.com
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*
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* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/.
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*/
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#include "bitops.hpp"
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#include "random.hpp"
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namespace ox {
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RandomSeed Random::DEFAULT_SEED = {540932923848, 540932540932};
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Random::Random(RandomSeed seed) {
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m_seed[0] = seed[0];
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m_seed[1] = seed[1];
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}
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uint64_t Random::gen() {
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// An implementation of the Xoroshiro128+ algorithm
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auto s0 = m_seed[0];
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auto s1 = m_seed[1];
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auto retval = s0 + s1;
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s1 ^= s0;
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m_seed[0] = ox::rotateLeft(s0, 55) ^ s1 ^ (s1 << 14);
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m_seed[1] = ox::rotateLeft(s1, 36);
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return retval;
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}
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}
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uint64_t ox_rand() {
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static ox::Random rand;
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return rand.gen();
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}
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