random.h

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/*
 * Copyright (c) 2010-2018, NVIDIA Corporation
 * All rights reserved.
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 *     derived from this software without specific prior written permission.
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#pragma once

#include <cugar/basic/types.h>


namespace cugar {


#define CUGAR_RAND_A 1664525
#define CUGAR_RAND_C 1013904223

struct IRandom
{
    static const uint32 MAX = 0xFFFFFFFF;

    CUGAR_FORCEINLINE CUGAR_HOST_DEVICE IRandom(const uint32 s = 0) : m_s(s) {}

    CUGAR_FORCEINLINE CUGAR_HOST_DEVICE uint32 next() { m_s = m_s*CUGAR_RAND_A + CUGAR_RAND_C; return m_s; }

    uint32 m_s;
};

struct Random
{
    CUGAR_FORCEINLINE CUGAR_HOST_DEVICE Random(const uint32 s = 0) : m_irand(s) {}

    CUGAR_FORCEINLINE CUGAR_HOST_DEVICE float next() { return float(m_irand.next())/float(IRandom::MAX); }

    IRandom m_irand;
};

} // namespace cugar