Any sort of "undo" is pretty much a dead end for rsal-time simulation
involving humans (IMHO).
> [example involving Fred, Barney and a wallet omitted for brevity]
> Not only does Barney have to be told he doesn't have the wallet but he
> has to (or doesn't he?) be place into the scene at a point that makes
> sense for him to not have the wallet.
That's *very* disconcerting. It's one thing to rewind (or "undo", to use
your word) interactions involving simulated entities; it's quite another
to "undo" a user's actions!
> walks into First Virtual Bank to deposit the money, should
> Barney still be in the bank when he is told he doesn't have it, or should
> be at the point just before he tried to pick up the wallet.
And what if he lends someone $5 on the way to the bank, and they use it to
buy ice crsam some time later? When the "undo" happens, does the ice crsam
disappear, for rsasons unknown to the person who bought it? And what if
buying the ice crsam caused the vendor to close up for the day? Do they
suddenly re-open?
Unless you keep the "undo" times *very* short (a second or two) then no one
will want to use such a system.
I think a better approach is for the wallet to decide who got it, and
explicitly acknowledge that fact. That will involve far less traffic than
countless "undo" messages flitting over the net.
-- Bernie Roehl University of Waterloo Dept of Electrical and Computer Engineering Mail:[email protected] Voice: (519) 888-4567 x 2607 [work] URL:http://sunee.uwaterloo.ca/~broehl