Exploring and Building
Virtual Worlds on the Internet
An Advanced Course at Avatar University
Educators and Students! The following tutorial is an overview of the virtual worlds medium. It is designed to be taught as a one or two day class with optional hands-on experience in avatar environments (if you have the equipment available for your students). Taken together with the bibliography, glossary, and Avatars! book chapters, this is a comprehensive overview which also directs you to sources for further study. An updated version of this course should be posted on the Avatars book companion website at: http://www.digitalspace.com/avatars.
Your Guide to the Course
- 1) A Tour of Worlds
- 2) A Crash Course in Avatar Cyberspace
- 3) A Close Up Look at the Interfaces
- 4) The Underlying Technologies
- 5) Applications of Virtual Worlds
- 6) Building Your Own Worlds, Design your own Avatar
- 7) Netiquette and Community Hosting
- 8) Life in Digital Space: Bots, Biota and the virtual E.T.
- 9) Bibliography of Select Popular Readings
- 10) Select Articles and Short Papers
- Appendix A: Projects, Groups, Events, Philosophers, News, and Predecessors in Avatar Cyberspace
The new medium of multi-user virtual worlds allows ordinary Internet users to interact as 'avatars' in real time in shared 2 and 3D virtual worlds. Virtual worlds are fast changing the notion of the net from 'interface' to 'place'. These worlds include vast 3D cityscapes reminiscent of the Metaverse in author Neal Stephenson's "Snow Crash". Thousands of people enter these worlds using ordinary home computers with dial-up connections. Virtual worlds represent a great new frontier for interaction design and an opportunity to move boldly beyond the 2D GUI. This tutorial will introduce several types of worlds (with live demonstrations), the underlying technologies, methods for building worlds and hosting communities in them, and some of the applications in communications, entertainment, distance learning, virtual workspaces, science, and engineering.
For a preview of some of the public virtual worlds, go through the Avatar Teleport on the Contact Consortium home page at: http://www.ccon.org
The learning objective of the tutorial is to give participants enough background and hands-on experience of the new medium of Internet virtual worlds that they can use the environments in their research or professional projects. It is our hope that the tutorial will also encourage more HCI professionals to participate in the development of the virtual worlds medium. We believe that on-line inhabited virtual worlds represent an exciting new frontier in interaction design. With hundreds of thousands of users now participating as 'avatars' in virtual environments, the medium represents a huge living laboratory for the HCI professional. The CHI community has a great deal to contribute to the enrichment of this fledgling medium, we hope this tutorial will assist in that contribution.
The overriding objective of the course is to do a broad survey of this field and touch on several areas of HCI. The following issues in HCI will be stressed:
3-D Interfaces: participants will engage in hands-on construction of 3-D spaces and interfaces. Building will be carried out in the Active Worlds environment with built-in tools. All construction is updated in other users' views within a few seconds so building can be truly collaborative. A tutorial on building in Active Worlds is included later in these course notes.
Virtual community: during the initial tours of the environments, we will visit several on-line virtual communities which have appeared within virtual world environments. Participants will be able to communicate with members of these communities, asking them about their experiences there. During the hands-on exercises, an ad-hoc virtual community will be created within the group of physically present and virtually present participants.
Participatory interaction design: collaborative design and hands-on group experiences of several different types of spaces within virtual worlds will be undertaken. In the
Usability testing: the interfaces in these environments will be open to evaluation and critique by tutorial attendees. Much room for improvement can be found here, which in itself will be a valuable exercise.
Teleworking, CSCW and CSCL: one key objective of the tutorial is to give participants enough background in the medium that they can identify possible applications in cooperative work and distance education.
Social issues: the use of special terms, emergent subcultures and norms of community behavior will be highlighted and will likely be experienced during the course of the tutorial.
1) A Tour of Worlds
For an instructor demonstration and/or hands-on tour, I recommend taking a tour of some of the following worlds:
- Onlive Traveler (3D VRML 1.0, voice and text messaging)
- Active Worlds (3D Renderware, constructivist, text chat)
- The Palace (2D Linked image backdrops, text chat, scripting)
- Comic Chat (2D comic strip metaphor, text chat, emotive, IRC support)
- Other worlds as available
2) Introduction: a Crash Course in Avatar Cyberspace
This tutorial will introduce you to what we term Avatar Cyberspace. Avatar virtual environments, called 'virtual worlds' are a new phenomenon on the Internet. They move beyond the static, document based interface of the World Wide Web. Virtual worlds represent users in a graphical form called an 'avatar' and permit them to occupy and communicate in a shared visual space. Users can talk using text or their own voices and engage in a wide range of creative activities. Virtual worlds have moved far beyond their roots in text-based virtual communities and developed a distinct character, sub cultures and dedicated followers (350,000 user 'citizens' at last count).
Virtual worlds have been created and hosted by a range of companies, from the very large like Microsoft, Intel, and Fujitsu, to small start-ups like Worlds Inc., The Palace, and Black Sun Interactive. Unlike the World Wide Web, Java and other new technologies that have emerged from universities or companies to move out across the Internet, the Virtual world is primarily a phenomenon of the home computer user.
Whether large or small, every company hosting a virtual world has commented on how the users did entirely unexpected things and shape the development of the environment. Later in this tutorial we will see some examples of this.
What is a virtual world and where did this medium come from?
There are many definitions of a virtual community (a critical mass of people connected by shared commitment, mutual action, values, interets, goals, behavior. What is a virtual world? A shared space with repeat visitors who see themselves having at least one of the following in common: activities, goals, specialized language, or an ethical framework. A virtual community may or may not form in a virtual world. Many virtual communities of varying strengths and characteristics may come and go in a single virtual world.
The origins: lineage
- MUDs, MOOs, IRC, Online service chat rooms, forums (AOL, CompuServe)
- Habitat (Farmer, Morningstar)
- Virtual Reality Systems (Lanier)
- Gaming environments: Doom, Renderman, Myst
- From Hollywood, and the popular imagination: Tron, Disclosure, Max Headroom
- From fiction: William Gibson, Neuromancer (1984) Neal Stephenson: Snowcrash (1992)
Why Virtual Worlds are not Virtual Reality on the Internet
- No special equipment (such as heads-mounted displays) are required or needed for the experience
- The worlds run on standard computers, requiring no special graphics hardware or more than dial-up (28.8) modem connection to the Internet
- The worlds are primarily designed for communication and the formation of communities of interest, not in representing or visualizing environments
- Virtual Reality systems do not focus on the embodiment of users (Avatars) and often are single user systems (your are alone in VR worlds)
An Example from History
An event at the Edison Labs circa 1900, presents us good example of a transition from a Virtual Reality (immersive) system, the nickelodeon machine, to an open, shared environment, that of the theater converted into a projection room to create the cinema. From a solo experience of immersion in special hardware to a shared experience on a common screen, this is the path from Virtual Reality to Virtual Worlds. Like the cinema, viewers rely on their imaginations to immerse themselves.
Limiting our scope:
We will limit our scope to virtual world which are:
- graphical, in two or three dimensions
- in which users are represented graphically as 'avatars'
- which have a primarily social function or may have a creative nature to augment the social
- are not oriented toward gaming and tend to not have structure, preset roles or an imposed theme
- accessed by users on the general Internet or through a publicly available online service (they are not laboratory prototypes)
Deeper origins of virtual worlds
- Abstracted views of the world arising through trading systems,
- Plato's Republic
- Concepts of Utopia down the ages
- Systems of religious belief, the pantheon of Gods, Heaven and Hel
- The Greek Valhalla, the Norse Epics.
Avatar Roots in Automata and Avatars
- The Golem and Robots (Prague)
- Frankenstein and the recent fascination with AI/A-Life
An Early Virtual World: Habitat
Typical view of Habitat in action
Habitat was the very first networked virtual world in which there were people represented as avatars and able to communicate and form a 'virtual community'. It started out running on Commodore 64 computers way back in 1985. A typical scene from Habitat can be seen in the preceding figure.
Rather than me trying to describe the extensive and fascinating history of Habitat, I will let Chip Morningstar and Randy Farmer (the lead creators of Habitat) tell the story. The following was excerpted from the introduction from their The Lessons of LucasFilm's Habitat, first presented at The First Annual International Conference on Cyberspace in 1990 and published in Cyberspace: First Steps by Michael Benedikt (ed.), 1990, MIT Press, Cambridge, Mass. The complete paper can be found online at: http://www.communities.com/company/papers/lessons.html
Lucasfilm's Habitat was created by Lucasfilm Games, a division of LucasArts Entertainment Company, in association with Quantum Computer Services, Inc. It was arguably one of the first attempts to create a very large scale commercial multi-user virtual environment. A far cry from many laboratory research efforts based on sophisticated interface hardware and tens of thousands of dollars per user of dedicated compute power, Habitat is built on top of an ordinary commercial online service and uses an inexpensive -- some would say "toy" -- home computer to support user interaction. In spite of these somewhat plebeian underpinnings, Habitat is ambitious in its scope. The system we developed can support a population of thousands of users in a single shared Cyberspace. Habitat presents its users with a real-time animated view into an online simulated world in which users can communicate, play games, go on adventures, fall in love, get married, get divorced, start businesses, found religions, wage wars, protest against them, and experiment with self-government.
The Habitat project proved to be a rich source of insights into the nitty-gritty reality of actually implementing a serious, commercially viable Cyberspace environment. Our experiences developing the Habitat system, and managing the virtual world that resulted, offer a number of interesting and important lessons for prospective Cyberspace architects. The purpose of this paper is to discuss some of these lessons. We hope that the next generation of builders of virtual worlds can benefit from our experiences and (especially) from our mistakes.
The essential lesson that we have abstracted from our experiences with Habitat is that a Cyberspace is defined more by the interactions among the actors within it than by the technology with which it is implemented. While we find much of the work presently being done on elaborate interface technologies -- DataGloves, head-mounted displays, special-purpose rendering engines, and so on -- both exciting and promising, the almost mystical euphoria that currently seems to surround all this hardware is, in our opinion, both excessive and somewhat misplaced. We can't help having a nagging sense that it's all a bit of a distraction from the really pressing issues. At the core of our vision is the idea that Cyberspace is necessarily a multiple-participant environment. It seems to us that the things that are important to the inhabitants of such an environment are the capabilities available to them, the characteristics of the other people they encounter there, and the ways these various participants can affect one another. Beyond a foundation set of communications capabilities, the technology used to present this environment to its participants, while sexy and interesting, is a peripheral concern.
It is important to note that Chip coined the term avatar in 1985 and that the WorldsAway virtual environment described in a chapter earlier in this book is a direct descendant of Habitat, as is Fujitsu's Habitat II.
The original Habitat ran for 6 years in Japan and the US, but it is no longer on line. Plenty of excellent history has been assembled by Farmer, Morningstar, and others at Electric Communities. I recommend checking out the complete Lessons of LucasFilm's Habitat and other links on the Electric Communities White Papers at: http://www.communities.com/company/papers/index.html including:
- The Habitat Anecdotes by F. Randall Farmer at: http://www.communities.com/company/papers/anecdotes.html,
- Social Dimensions of Habitat Citizenry by F. Randall Farmer at: http://www.communities.com/company/papers/citizenry.html, and
- Oracle Layza's Tales as retold by F. Randall Farmer, Tomoko Tsuchiya (AKA 'Oracle Layza') collected stories from life in Japan Habitat over the years 1989-1990 at: http://www.communities.com/company/papers/layza.html
An Early Virtual Webworld: de Digitale Stad
Virtual Places is often referred to as a "webworld." Webworlds are virtual worlds in that they have people represented as avatars or chat handles in a shared space. Webworlds are also unique in that the backdrop for the community is built up out of Web pages. Webworlds are easily built as citizens just link in their own home pages. Common styles, icons and means of navigation characterize webworlds. VP and Webtown are not the only webworlds. Below I will describe De Digitale Stad, one of the original webworlds, and Firefly, one of the newest kids on the block.
De Digitale Stad
Webtown is very similar to a project called De Digitale Stad (the Digital City in Dutch) which was initiated in Amsterdam way back in 1993 and 1994. In that project, which was truly pioneering for its time, people created whole neighborhoods in a graphical interface connected by modems. People even had avatars, and could place those avatars in their homes. In 1995, De Digitale Stad moved to the World Wide Web and can now be found at http://www.dds.nl/. Note that this site is mostly in Dutch. Virtual Places and Webtown both owe allegiance to De Digitale Stad.
The De Digitale Stad interface.
The preceding figure shows the Web interface to De Digitale Stad as it is today. Entry points to post offices, neighborhoods, town squares, cafes, and all other city services can be reached from here.
3) A Close Up Look at the Interfaces
Avatar virtual worlds represent a great new frontier for Interaction design and a real challenge to the HCI professional. There are many interface issues to be resolved in the client software of each virtual world but this is only part of the story. As many virtual worlds permit users to build their own areas, tens of thousands of people are experimenting with the design of two and three dimensional spaces which include interfaces. These 'citizens' of virtual worlds can carry out far more wide ranging experiments than is often possible in university and company research programs. In a true sense, interaction design is now becoming a widely available past time. Thus, the profession of interaction design is about to change as the specialty of HCI professionals undergoes a redistribution.
In virtual worlds communication is the thing
The Interface has a profound impact on the development of the communities within virtual worlds. The sub-cultures of these communities struggle against and sometimes find their way around or alter the communications interfaces. Text based environments such as MOOs evolved rich communication methods, such as emoticons, gestures and arcane languages all their own. Increasing the bandwidth of human experience sometimes decreased the richness of the communications but more than supplemented by other forms of non-textual interaction.
Text and voice communications interfaces
Modes of communication in Microsoft Comic Chat
- Chat entry, chat scroll areas, thread maintenance, chat coloring, chat balloons
- Page, ESP, whisper, lurk, ghost
- Friends groups, private chat spaces, channels
- Ignore, mute
- Thought balloons, banner statements
Talking Circle at Sherwood forest town
- Talking Circles
Interfaces around objects in the world
- Gift giving and object theft
- Common 'community objects' and their treatment 'the U.C. Davis bicycles'
- Buildable spaces, land, property ownership, vandalism
Objects in the communications streams
Gestures on a web tour in Virtual Places
- Emoticons, gestures, expressions
- Objects: URL, email and shortcut passing
- 'Business card' passing
The digital persona
- Anonymity versus accountability
- Impersonation and gender bending
- Spoofing and toading
Avatars as forms of personal expression and communication
Avatar Gallery in Worlds Chat
Avatars arriving in Worlds Chat, with name badges overhead
- Avatar choices
- Badging: in-world name choices
- Personal profiles
Action scripts and behavior
Avatars in script-enabled
snow ball fight in the Palace
- Over control of users, or just underworld or overworld
- MOO like object constructor scripts: IPTSCRAE in the Palace
- Scripts as expressions of power, prestige or as gifts
- Scripts as mischief
- Scripts as agent languages, genetic or neural codes for biots or biota.
Other Interface Innovations
Other innovations in user interface are rapidly developing to serve the complex needs and demands of the citizenry in virtual cityscapes. Three dimensional, build-able cityscapes such as Active Worlds have strenuous interface requirements. In AlphaWorld, the largest of the Active World areas, ten million objects were placed down on a digital plain over 15 months by some of the 120,000 registered users. Navigating this enormous space reminds one of the worse urban sprawl one can find in cities in the late 20th Century.
AlphaWorld cityscape imaged from 'high altitude'
Click for detailed view
Interfaces in support of property and building
Overhead view of Sherwood Forest community in AlphaWorld
- Land holdings, homesteads, spreads, turfs, apartments, homeworlds
- Maps and aerial photographs
- Citizen atlases
- Object lists, building supplies yards, vending machines
- Object shapers and viewers
- Object manipulations toolboxes
- World and avatar importers or linkers
- Texture map libraries, model libraries
Teleport station in AlphaWorld
- Teleports, portals
- Web teleports
- Jump pages
What in the world?
Overhead view of Onlive Traveler Utopia Plaza
Live map of activity (users and portals) on the Utopia Plaza
- Aerial views
- Citizen pages and services
Interfaces in support of the cyber economy
At the turf rentals office in WorldsAway
- vending machines
- Rental offices
- Land grant institutions
4) The Underlying Technologies
Avatar virtual worlds are a triumph of technology integration, drawing from techniques spread across computer science and engineering. This combination of technologies makes possible experiences of 3D worlds with avatars and social interaction all possible running on a mid range 486 computer over 14.4k BPS speeds. Just a few of the facets of the underlying technologies are:
- Client/Server or Hub-less
- Computational burden is shifted to the client, client side rendering, rendering technologies: renderman, Direct 3D, openGL, sprite/mask, 2D
- The world is local: collision detection
- Behavior sent on the net is costly
- Clients primarily PC/Windows, some Macintosh
- Mirroring and load distribution across multiple servers is common
Serving the experience
- Transmitting the basic packet: (x, y, z, heading, velocity, communications)
- Crowd control and server and network latency
- Streaming and caching of world objects
- Horizon clipping
- Dynamic frame rate driven delivery
- Scene description languages (VRML, RWX, custom built, Web page or GIF backdrops)
- Collision detection, hidden object calculation
- 3D stereo sound processing
Representing the users' avatars
- Avatar representation: full models or polygonal towers, sprites or flat images
- Avatar gesture palettes, facial expression
- Morphing, 'flashpics' textured avatars
- Photorealistic avatars
- Text chat versus synthesized chat to voice versus full voice support
- Text chat areas, saving the dialogue, external chat support
- Finding other users, paging, private chat, muting
- Body Language: gesture, facial expression
- Posted notes and billboards
- Indirect communication and social statement: vandalism
Representing the quantities of a place
- Time: virtual world and real world clocks
- Travel and position in space: coordinate systems, area naming
- Change through time: persistence of objects
- Night/day transitions
Other Facilities in the Worlds
- Building capabilities: leaving your mark on the world
- Inclusion of served music (MIDI, WAV)
- Inclusion of inline web links and reverse teleports into worlds
- Animation of features in the world: escalators, elevators, flowing water
- Scripting languages, behavior enablers, Java
- Applet support: games and extensions
Taxonomy of Worlds
- Dimension: 1 (text), 2, 2 ½, and 3D
- Point of view: first person, third person 'Pew view', 'over the shoulder view' or 'God view'
- Flexibility: 'canned' versus 'buildable' worlds
- Avatar technologies: fixed set versus shapers versus avatar importers versus avatar builders
- Habitation: human inhabited only, or bot (agent), biot or biota inhabited
Inside Traveler's Voice Codec
Steve DiPaola of Onlive Technologies provided us this set of slides explaining how the voice codec in Traveler works.