FNV

Fowler–Noll–Vo or FNV is the hashing system used by MySims to hash various names.

FNV32 vs FNV64

MySims specifically used FNV32 for uint32's and FNV64 for uint64's. In practice this means shaders names and groups use FNV32 while instances use FNV64.

Algorithm

In pseudocode, taken from Wikipedia

algorithm fnv-1 is
    hash := FNV_offset_basis

    for each byte_of_data to be hashed do
        hash := hash × FNV_prime
        hash := hash XOR byte_of_data

    return hash 

In CSharp, taken from MySims Editor.

Note that strings are first lowered before being converted to bytes.

public static class FNV
{
    private static readonly uint PRIME_32 = 0x01000193;
    private static readonly ulong PRIME_64 = 0x00000100000001B3;
    private static readonly uint OFFSET_32 = 0x811C9DC5;
    private static readonly ulong OFFSET_64 = 0xCBF29CE484222325;

    public static uint Create32(byte[] bytes)
    {
        var hash = OFFSET_32;

        for (int i = 0; i < bytes.Length; i++)
        {
            hash *= PRIME_32;
            hash ^= bytes[i];
        }
        return hash;
    }

    public static ulong Create64(byte[] bytes)
    {
        var hash = OFFSET_64;

        for (int i = 0; i < bytes.Length; i++)
        {
            hash *= PRIME_64;
            hash ^= bytes[i];
        }
        return hash;
    }

    public static uint FromString32(string str)
    {
        return Create32(Encoding.UTF8.GetBytes(str.ToLower()));
    }

    public static ulong FromString64(string str)
    {
        return Create64(Encoding.UTF8.GetBytes(str.ToLower()));
    }
}