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[Solved]Is it safe to assume that Animator.StringToHash() should never return zero?

Discussion in 'Editor & General Support' started by neginfinity, Feb 1, 2018.

  1. neginfinity

    neginfinity

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    Jan 27, 2013
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    Is it safe to assume that Animator.StringToHash() would never return zero for a valid string?

    I'd expect this to be the case for non-null strings... but documentation does not guarantee it.

    I also cannot exactly execute IL code of this particular function...
     
    neginfinity, Feb 1, 2018
    #1

  2. karl_jones

    karl_jones

    Unity Technologies

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    Animator.StringToHash uses CRC32. So, in theory, it is possible that it could return 0 as a hash.
    It will also return 0 if the string is null.
     
    karl_jones, Feb 1, 2018
    #2
    rockin likes this.

  3. neginfinity

    neginfinity

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    Thanks for the reply.

    I've re-checked CRC32 algorithm and it indeed can return zero.
    I've redesigned the code not to assume that some hash values are invalid.

    However.... I think this is an important detail and should be reflected on documentation. Currently documentation doesnt' say which hash algorithm is used by StringToHash.
     
    neginfinity, Feb 1, 2018
    #3

  4. karl_jones

    karl_jones

    Unity Technologies

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    Good point. We will add something to the docs.
     
    karl_jones, Feb 1, 2018
    #4

  5. neginfinity

    neginfinity

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    Thanks. Marking the thread as solved.
     
    neginfinity, Feb 1, 2018
    #5
    karl_jones likes this.