Re: Portals vs Links

Jon Green ([email protected])
Fri, 5 May 1995 10:09:59 +0100 (BST)


In a possible past, Chris Marrin said:

> - When a visitor leaves, the server removes his/her name from the list of
> current visitors and removes the Avatar from its object store.
>

What was your strategy for dealing with the situation where,
frex, a visitor enters the room and their system/browser crashes
leaving their (orphaned) avatar "stuck" at a remote server?

I'd suggest two methods for getting over this (not mutually
exclusive):

1. Time-and-motion: if the avatar hasn't moved for a
while, its image starts to degrade - either fading or
incrementally losing detail to other observers, ending
up as a wireframe and eventually going;

2. Reverse polling (world server->client) "pings" the
client for continued existence (and presence in the area).
If there's no reply within a timeout period, the client's
avatar degrades much faster (and is allowed to vanish
completely). If the client's s/w disavows an avatar at
that location, the client's avatar is assumed to have
left, incommunicado.

-- 
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