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Hash key for vector of 3 ints


Hi all,
I'm currently creating my hash key by stuffing the bits into an
unsigned long long.

key = static_cast<uin t64>(x) | (static_cast<ui nt64>(y) << 20) |
(static_cast<ui nt64>(z) << 40);

But this limits the range in x,y,z.

I've made a few attempts in Visual Studio including making an XOR of
the vector ints.
I don't think the XOR gives keys that are unique enough.

error C2440: 'type cast' : cannot convert from 'const vector3i' to
'size_t' c:\program files\microsoft visual studio 8\vc\include
\xhash
Anyone have an example or hints?
thanks

Apr 9 '08 #1
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