Re: [vwrap] Consensus? What exactly should be in the protocol

[David W Levine <[e-mail]>]

So. I guess I'm deeply confused. The Remit of WRAP, for a lot of reasons
is:
"SecondLife Like" worlds. Which is to say worlds in which there is a server
from which one gets the state of the virtual simulation.  Which is to say
that
a client connects, and says "Please place an avatar here and tell me what's
happening
around here"  (which implies a whole bunch of other stuff, but put that to
one side for a moment)

The vwrap specs have always marked the client as web endpoint which sends
requests and gets back responses. There has been some interesting
discussion and
debate about to efficiently keep a client informed about the scenegraph
they are
interested int, but it rather does follow the web model.

"Dear server, I want to know about X"
"Dear client, here is what's at X"

with the fun of "Oh, and here is what's at X now, and Now, and Now, and
Now" because the scenegraph
is constantly changing.  It doesn't tell the client what to do, and we've
talked at length about how to
use content negotation, mime types and such to let the client and the
server do web style negotiation about
what the client wants to see. (and this is very much marked as extensible,
exactly as Morgaine's been repeating)

Further, the "Client/Sim" part is, in many ways, the least interesting part
of the spec. The ongoing discussion has
always been that for the time being it just would re-use Linden's basic
pipes, not because they were lovely
but because they worked, there is content, there is a clienbt, there is
OpenSim, and it's useful to move forward.

The heavy lifting has always been in the form of "I have a shape X, and a
set of parts attached to me" which I want to bring
with me to "virtual space X" That's only related to the client to the
extent that at some point, all the clients connected to
a region need to share a set of things they can display (with content
negotiation mixed in) or the shared experience
becomes "Woah, John's a dragon? He looks like a blue blob to me"

I think there's a huge amount of "assuming"  going on here, and it's
frustrating as all get out.

- David
~Zha



                                                                                                                                   
  From:       Cristina Videira Lopes <[e-mail]>                                                                           
                                                                                                                                   
  To:         [e-mail]                                                                                                    
                                                                                                                                   
  Cc:         David W Levine/Watson/IBM@IBMUS, [e-mail], [e-mail]                                              
                                                                                                                                   
  Date:       09/22/2010 03:00 PM                                                                                                  
                                                                                                                                   
  Subject:    Re: [vwrap] Consensus? What exactly should be in the protocol                                                        
                                                                                                                                   





Cristina Videira Lopes wrote:
> You can dictate that. But then this will be completely irrelevant in a
> couple of years when WebGL is actually usable or when Google finishes
> their virtual machine for running safe native code on browsers.
...or when server-side streaming goes mainstream, and being in a virtual
world is as simple as running a video player plus a few
JavaScript/native back channels to the server.

First point is: according to the Web principles, each web application
controls 100% what and how the client gets via this really powerful
concept of hypermedia. It is unlikely that the world is going to adopt a
standard that forces implementers to take several steps back on this
kind of autonomy. The diversity is what gives service providers an edge.

The second point is: when we have all that variety of viewer
implementations that are all equally accepted by the web browser, we are
still to cope with portability of user agent simulation state between
those worlds -- and that's the bottom line for interoperability of
virtual worlds on the Web. I'm interested in this, because it's much
more foundational than the variety of virtual world implementation options.