Multi-User Virtual Environments
![](ring1.gif)
Thomas Funkhouser
Overview:
Multi-user virtual environment applications incorporate computer graphics,
sound simulation, and networks to simulate the experience of real-time
interaction between multiple users in a shared three-dimensional virtual
world. Each user runs an interactive interface program on a ``client''
computer connected to a wide-area network. The interface program simulates
the experience of immersion in a virtual environment by rendering images/sounds/etc.
of the environment as perceived from the user's simulated viewpoint. Each
user is represented in the shared virtual environment by an entity rendered
on every other user's computer. Multi-user interaction is supported by
matching user actions to entity updates (e.g., motion/sound generation)
in the shared virtual environment.
Applications for multi-user virtual environment technology include distributed
training, simulation, education, home shopping, virtual meetings, and multiplayer
games. For example, consider a virtual city in which multiple users interact
in real-time. As each user moves through the city, a graphical representation
of that user is displayed moving on each other user's screen. When any
user talks into a microphone, his/her voice is played with appropriate
stereo control so as to appear to come from the position of the entity
representing the speaker. Social interactions and commerce might be more
compelling with a 3D virtual city interface incorporating both graphics
and sound than with textual or 2D multimedia interfaces such as those employed
by current chat programs and browsers for the world wide web.
We have developed network services that support multi-user virtual environments
via a client-server design. The idea is to include multiple server computers
that processing information, maintain storage, and manage communication
for their clients. So far, servers have been implemented that perform message
processing, interaction detection, and voice bridging. In the near future,
we hope to build servers for persistent storage of updates in the virtual
environment. Using our servers, we are able to support multi-user virtual
environments that are more realistic, more scalable, more interactive,
and more affordable than is possible with a peer-to-peer system design.
Related Publications:
-
Thomas A. Funkhouser, Patrick Min, and Ingrid Carlbom,
Real-Time Acoustic Modeling for
Distributed Virtual Environments,
SIGGRAPH 1999.
-
Thomas A. Funkhouser.
Network Topologies for Scalable
Multi-User Virtual Environments.
IEEE VRAIS `96, San Jose, CA, April, 1996.
-
Thomas A. Funkhouser.
Network Services for Multi-User
Virtual Environments.
IEEE Network Realities `95, Boston, MA, October,
1995.
-
Thomas A. Funkhouser.
RING: A Client-Server System for
Multi-User Virtual Environments.
Computer Graphics (1995 SIGGRAPH Symposium on Interactive
3D Graphics), Monterey, CA, April, 1995, p. 85-92.