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#ifndef RixRNGInline_h

#define RixRNGInline_h


// Convenience functions that can be used to generate sample values.

// This file is included by RixRNG.h.


#include "prmanapi.h"                   // for PRMAN_INLINE


namespace RixRNGUtils

{


// Compute a repeatable random float in [0,1) based on value and scramble

PRMAN_INLINE float

HashToRandom(const unsigned value, const unsigned scramble)

{

    // clang-format off

    unsigned result = value;

    result ^= scramble;

    result ^= result >> 17;

    result ^= result >> 10;  result *= 0xb36534e5;

    result ^= result >> 12;

    result ^= result >> 21;  result *= 0x93fc4795;

    result ^= 0xdf6e307f;

    result ^= result >> 17;  result *= 1 | scramble >> 18;

    return static_cast<float>(result) / 4298115584.0f;

    // clang-format on

}


PRMAN_INLINE unsigned

shufflePattern(

    const unsigned pattern,

    const unsigned scramble1 = 0xb2182ef5,

    const unsigned scramble2 = 0x1e1897a7)

{

    unsigned npattern = pattern * ((scramble1 << 1) | 1);

    // All odds are coprime with 2^16.

    npattern += scramble2;

    return npattern;

}


} // namespace RixRNGUtils


#endif