Constants.h

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 * MIT License
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#pragma once
 
#include <cstdint>
 
namespace nfx::hashing::constants
{
    //=====================================================================
    // Hash algorithm constants
    //=====================================================================
 
    //----------------------------------------------
    // FNV-1a hash algorithm constants
    //----------------------------------------------

    inline constexpr uint32_t FNV_OFFSET_BASIS_32{ 0x811C9DC5 };

    inline constexpr uint32_t FNV_PRIME_32{ 0x01000193 };

    inline constexpr uint64_t FNV_OFFSET_BASIS_64{ 0xCBF29CE484222325ULL };

    inline constexpr uint64_t FNV_PRIME_64{ 0x00000100000001B3ULL };
 
    //----------------------------------------------
    // Integer hashing constants
    //----------------------------------------------

    inline constexpr uint32_t KNUTH_MULTIPLIER_32{ 0x45d9f3b };

    inline constexpr uint64_t WANG_MULTIPLIER_64_C1{ 0xbf58476d1ce4e5b9ull };

    inline constexpr uint64_t WANG_MULTIPLIER_64_C2{ 0x94d049bb133111ebull };
 
    //----------------------------------------------
    // Hash combining constants
    //----------------------------------------------

    inline constexpr uint32_t GOLDEN_RATIO_32{ 0x9e3779b9 };

    inline constexpr uint64_t GOLDEN_RATIO_64{ 0x9e3779b97f4a7c15ULL };

    inline constexpr uint64_t MURMUR3_MULTIPLIER_C1{ 0xff51afd7ed558ccdULL };

    inline constexpr uint64_t MURMUR3_MULTIPLIER_C2{ 0xc4ceb9fe1a85ec53ULL };
 
    //----------------------------------------------
    // Seed mixing constants
    //----------------------------------------------

    inline constexpr uint64_t SEED_MIX_MULTIPLIER_64{ 0x2545F4914F6CDD1DUL };
} // namespace nfx::hashing::constants