[vtk-developers] hast table in VTK

[Moreland, Kenneth]

> If all you want to do is store objects in a hash table for 
> fast lookup, just use the pointer value as the hash key.  You 
> can just copy the pointer value to an integer and then send 
> it through a hash function.

The pointer value is not always a valid value to hash on.  Sometimes
objects that have different pointers can be considered equal.

-Ken