Re: www-vrml-digest V1 #13

Robin Hayes ([email protected])
Sun, 4 Jun 1995 18:45:15 -0700


On Jun 2, 11:36pm, Nicky wrote:
> Subject: Re: www-vrml-digest V1 #13
> I've got a quick point. It has been partially addressed by someone who
> mentioned that most of the VRML files on the Web now are simply direct
> conversions from CAD, 3DS (perhaps via LVS) and so on...and are hence,
> as they put it 'flashy demos..'.
>
> To a certain extent I agree and I wanted to illustrate my concerns with
> a simple (albeit fundamentally incorrect) analogy.
>
> 3DS (via LVS)->iv->wrl gives 5 Mb file (forgetting gzip discussions for
> now.)
>
> simple authored vrml file is circa 1kB (OK maybe a bit more)
>
> Doesn't this remind you of something....???
>
> simple authored html page is circa 2 kBs. A big image as a web page is,
> well almost anything but let's say 0.5 Mbs....
>
> Now OK of course it looks better as a big image but the principle here
> is communication. Perhaps I'm taking this line because I ahve no access
> to powerful 3D authoring tools (even though I'm on an Indy I'm stuck
> with Inventor, Showcase and the perennial favourite, ASCII editing) and
> to be honest I'm kinda glad it started this way since otherwise, I may
> have fallen into the trap of the California way - Style before Substance.
>
> You may argue that VR on the net is developing so who gives a shit of
> only 100 people worldwide want to access this - in fact if hard pushed I'd
> probably argue the same thing - but the key point is that unless people
> use this stuff it's gonna go the way of the VIC 20. I have no fears that
> VRML is gonna live forever (well at least till we have an Onyx on every
> desk) - but I think the most dangerous trap to fall into is one of
> allowing ourselves to think
> "Oh, it's OK - we can keep doing ultra cool models in 3DS etc, 'cause
> Mark'll make the next version really compressed."
>
> We can do 3D models now for minimal amounts of time and memory. I am
> still new to VRML but I'm learning quickly but what I had in mind is
> stuff like
>
> Robin Hayes' space (off the main Webspace page)
>
> or even my primitive efforts at
>
> http://fourier.civil.gla.ac.uk:1500/htdocs/nickvr.html
> [yes, there's very little there but it'll get better]
>
> If people thought like that when html first came out the web would never
> have grown to the size it is now 'cause no one would sit waiting for the
> downloads.
> (I feel necessary to point out that I'm not a sceptic - I've waited
> hours for glimpses of snapshots of 3D scenes not to mention scenes
> themselves. - it's the other rabble I'm concerned about - you know those
> guys who really determine whether something becomes a Netscape1.1 or a
> DeLorean)
>
> Thanks for your time.
> Nick
>
> -------------------------------------------------------------------.
> He who dies with the most toys...
> Still dies.
>
> [email protected]
> http://sw.cse.bris.ac.uk/public/cindy.html
>
>
>-- End of excerpt from Nicky

Thanks for your kind words about my humble efforts, while that model
seems to have come up, let me say a few things about it, and about how I view
some of the threads being discussed right now. (I prefer to lurk, but when
my name comes up, I'm more than happy to contribute :-)
The model was done in showcase and jot. I have no expensive 3-d modeling
software, and unless it becomes MUCH less expensive, I will never buy any.
Showcase is a pretty good 3-d modeler as long as you stick to primitives.
However the most important modeling tool I have at my disposal is a good
text editor! Despite what people say they are working on, there are no 3-D
modelers that can both import and export VRML models right now.
The reason for the spectacular development of the web is that the
format of the files was completely open and human-readable. This meant that
anyone anywhere could use existing text-editing tools to quickly create large
amounts of content, sure editors that were specifically aimed at the web came
along eventually, and perhaps, in the future, most HTML authoring will take
place on tools like these, but what caused the GROWTH of the web was the fact
that ANYONE can do it. If we really want VRML to catch on like HTML did, the
most important factor is that people not be scared of it.
For this reason more than any, I think the entire thread of the
binary format is headed in the wrong direction, sure files need to be small
to transfer accross the net, but shouldn't that be up to the modeler?
I have discovered in my modeling experiments in VRML, that many 3-D
modeling programs create terribly inefficient models, up until now, this did
not really matter, very few real-time 3-D systems existed, and those that did
either had enough graphics horsepower to just deal with it, of had
sophisticated software capable of fixing the inefficiencies at parse-time.
This may have been because the programmers figured that no-one would see the
actual scene anyway, and software doesn't know the difference. Well those
days are gone now (thank goodness) and modeler writers will have to be
concerned with how efficient their models are, not just how pretty they look
when you ray-trace them. Rather than talking about how to compress
inefficient files to make them quicker to transmit, why not talk about how to
make these models more efficient, this will make them quicker, both to load
and to parse (and render if your browser isn't very smart).
While hand-editing VRML documents may seem inefficient, it is
actually not that bad. Cut-and-paste comes in handy as does the "delete"
function. Almost every model I have had to hack was at least twice as big as
it needed to be. Redundant Groups and Separators around individual objects,
normal definitions for objects that didn't need them, (use creaseAngle
correctly and you will find that VERY few objects really need to have normals
specified), redundant vertices in indexedFaceSet objects (a cubeoid can be
described with 8 vertices, many of modelers describe it using 36 vertices,
one for each corner of each triangle). These are issues that modelers and
whoever writes format-conversion programs should be worrying about not this
group, you've defined a format, now let's see how people use it before we go
off and re-design it. (One idea that has some merit however is shortening
the keyword names, with all due respect to the Inventor team, VRML is NOT
Inventor, why are we clinging to this long-winded sintax? Why use "rotation"
when "rot" is so much shorter?)

That's enough ranting for now, I'm sure that I've opened myself up for all
kinds of flames, so I will see what kind of responses I get before posting on
any of the other subjects I have opinions on :)

Robin ("Does an asbestos suit cause skin cancer?") Hayes

-rdh

Robin Hayes, Silicon Graphics Inc. (415) 390-2456