VRML Backgrounder

Mark D. Pesce ([email protected])
Sun, 19 Mar 95 23:59:53 -0800


Background Information on the Virtual Reality Modelling Language

The Virtual Reality Modeling Language (VRML) is alanguage for describing multi-
user interactive simulations -- virtual worlds networked via the global
Internet and
hyperlinked within the World Wide Web.

In 1969, the creation of ARPAnet, the forerunner of today's Internet, provided a
methodology through which users could remotely manipulate computers, and the
files stored on them. While this was a powerful extension of computing, it
was also
confusing; without any clear sense of "what went where", access to Internet was
restricted to the class of early "net surfers" who could remember where
things were
stored. Most everyone else, even technically sophisticated users of computers,
found it impossible to make sense of it.

In 1989, Tim Berners-Lee, a software engineer at the Center for European
Particle
Physics, CERN, developed a hypermedia system today known as the World Wide
Web. With the creation of the Universal Resource Locator, or URL,it became
possible to tell anyone "where to go and how to get there" for almost any
piece of
data on the Internet. Rather than a cryptic set of commands and accesses, the
URL created a standard addressing mechanism for the data hidden in cyberspace.
In essence, it turned the entire Internet into the equivalent of a single
(very large)
disk drive, and made it possible to create documents which could encompass data
from many different parts of the Internet, binding them together into a cohesive
whole.

Even the URL required some improvement. They're quite cryptic - for example, I
can only tell you how to get to the VRML Forum home page by saying,
"http://vrml.wired.com/", which is not really human-centered data, it's
computer-
centered data. I need to make an effort to remember it at all. As great as
it is, the
URL mechanism of the World Wide Web leaves a lot to be desired, particularly for
human beings, and we comprise the user base; the Web was built for people, not
for computers, and because of this, the Web has caused an enormous upsurge in
Internet traffic. Very soon, the bulk of the traffic on the Internet will
be Web-
generated.

A few years ago, research into "sensualized" interfaces began to receive
widespread attention in the press and the industry. A wide range of
technologies,
which collectively came to be known as "Virtual Reality", began a fundamental
change in the nature of the user interface, moving it to a human-centered
design;
where the space around the user became the computing environment, and the
entire sensorium was engaged in theinterface. All of this was in an effort
to make
computers more responsive to the humans who used them, and focused around a
basic realization: if something is represented sensually, it is possible to
make sense
of it.

Late in 1993, Mark Pesce, and Tony Parisi developed a three-dimensional
interface
to the Web which embodied many of the lessons learned in several years of
research in both virtual reality and networking. Upon communicating these
innovations to Berners-Lee, Pesce was invited to present a paper at the First
International Conference on the World Wide Web, in Geneva, Switzerland. During
a session to discuss virtual reality interfaces to the Web, atendees agreed
there
was a need for a common language to specify 3D scene description and WWW
hyperlinks -- an analog of HTML for virtual reality. The term Virtual
Reality Modeling
Language (VRML) was coined, and the group (headedby Pesce and Brian
Behlendorf, of WIRED magazine) began work on a VRML specification immediately
following the conference.

With the blessing of WIRED, Behlendorf set up an electronic mailing list to
facilitate
discussion of a specification for VRML. The response was overwhelming; within a
week, there were over a thousand members. The list membership quickly agreed
upon a set of requirements for VRML, and began a search for technologies which
could be adapted to fit the needs of it.

The list members proposed several worthwhile candidates, and after much
deliberation the list came to a consensus: the Open Inventor ASCII File Format
from Silicon Graphics, Inc. The Inventor File Format supports complete
descriptions
of 3D scenes with polygonally rendered objects, lighting, materials, ambient
properties and realism effects. It has all of the features that
professionals need to
produce high-quality work, and an existing tools base with a wide installed
presence.

A subset of the Inventor File Format, with extensions to support networking,
forms
the basis of VRML. Gavin Bell of Silicon Graphics has adapted the Inventor File
Format for VRML, with design input from the mailing list. SGI has publicly
stated
that the file format is available for use in the open market, and has
contributed a file
format parser into the public domain to bootstrap VRML viewer development.

VRML is designed to meet three criteria: platform indepencence;
extensibility; and
the ability to work over low-bandwidth (14.4 kBps modem) connections. Early on,
the designers decided that VRML would not be an extension to HTML, which is
designed for text, not graphics.

The next generation of Web browsers will understand and interpret VRML; here are
three examples of the kinds of projects VRML will enable:

The Interactive Media Festival Gallery Tour

The Interactive Media Festival (http://www.arc.org/) is an annual event of
world-wide
scope, which attracts some of the best talents of the new media. Their annual
gallery and awards event, which takes place in Los Angeles in early June,
will also
be modeled in VRML and linked into their own Web site. People anywhere in the
world will be able to tour the gallery space, examine the contestants'
works, and
follow links from these works other items of interest. In this way, IMF can
have an
international scope and an international reach.

WaxWeb 2.0

David Blair, the avant-garde filmmaker of WAX: or The Discovery of Television
Among the Bees, and Tom Meyer, a doctoral candidate at Brown University, spent
the last two years developing WaxWeb (http://bug.village.virginia.edu), a
hypermedia web version of the film. David and Tom have spent the last 8 months
bringing WaxWeb forward into VRML; at the release of WaxWeb 2.0 in the
beginning of April, it acquires a VRML component - when a user goes to the
WaxWeb VRML site, WaxWeb generates an assortment of rooms and links - but
no two journeys through WaxWeb are ever completely the same. At last count,
they'd created over 9000 (!) possible rooms to walk through, each of which
is rich
with content and anchors.

Virtual SoMa

The heart of the nation's multimedia industry is San Francisco's "Multimedia
Gulch", located in its "South of Market" neighborhood, nicknamed SoMa. Several
organizations have initiated a project to model SoMa in VRML and make it
accessible through the Web. As a pilot, the 10-block area between 1st and 3rd
Streets, from Howard to King, is being modeled as a VRML world. Many of the
organizations in this neighborhood already have a web presence; this model
links to
their web pages. You can take a stroll down the virtual 3rd Street, to the
block
between Bryant and Brannan, find the offices of WIRED, click on the
building, and
go to their home page in the web.

There are some areas where VRML is still incomplete. Except for the
hyperlinking
feature, the first version of VRML does not support interactive behaviors.
This was
a practical decision intended to streamline design and implementation.
Design of a
language for describing interactive behaviors is a big job, particularly
when the
language needs to express behaviors of objects communicating on a network.
Support for arbitrary interactive behaviors is critical to the long-term
success of
VRML; it will be included in the second revision of the VRML specification,
which
will be completed by December of 1995.

________________________________________
Mark D. Pesce
Managing Director,
The Community Company * 415.621.1981 * [email protected]