Parallel Worlds

1
Parallel Worlds
Abstract
Myriad
By Emily Echevarria, Sophomore, ECE Department,
UIUC
The Syzygy operating system controls a PC cluster
to render a virtual environment. With Myriad, an
extension of the Syzygy distributed graphics
system, peer computers can share of scenegraphs
and subgraphs. Myriad creates collaborative
virtual environments through scenegraph
filtering. This project continues Ryan Mulligan
and Andrew Ofishers Math 198 projects.
In this project we generate realtime multi-user
virtual environments on a Phleet of graphics
computers. A Phleet is a heterogeneous cluster
of peer computers connected through Dr. Ben
Schaeffers Syzygy operating system. In
tieSpline two peers interactively create
interwined, splined roller coasters. In avatars
multiple peers can enter the same virtual
environment. HorseWalk is a scenegraph of an
animated horse. Because of Schaeffer's Myriad
extension to Syzygy, a peer user makes a realtime
local change to a scenegraph that propagates to
select peer computers within the Phleet.
Advisor Professor George Francis, Math Dept.,
UIUC
avatars.py
HorseWalk.py
tieSpline.py
With feedback sharing, two users create a spline
on peer computers within the same virtual
environment. Each user selects an arbitrary
number of control points in three space with a
wand connected to the joystick. After the points
are selected intermediate points on a natural
cubic spline are calculated between the control
points. A Bezier frame represented by a TIE
fighter travels along the spline. Users share
the experience of flying on one anothers spline
by entering a cockpit mode in their instance of
the application.
With feedback sharing, one peer computer can make
a mainworld virtual environment. An arbitrary
number of users can add and update the movement
of an avatar subgraph on the mainworld. By
pulling the mainworld scenegraph avatars at any
peer computer can see the mainworld and the other
avatars present in the mainworld. Each avatar is
a separate instance of a subgraph, so each peer
computer modifies only the local subgraph.
The HorseWalk.py blobbyman model animation
implements the easy to use Visual graphics
library in the Python script becomes a Syzygy
distributed scenegraph application by means of a
portage. HorseWalk.py calls Ryan Mulligans
vportage class to change pythons visual library
commands into PySZG library commands. Now the
resulting distributed scene graph can participate
in peer-to-peer sharing applications.
This Syzygy distributed scenegraph is a port of
William Bakers Syzygy masterslave application,
splinester.py.
Integrated Systems Laboratory Beckman
Institute University of Illinois at
Urbana-Champaign
National Science Foundation
http//new.math.uiuc.edu/im2006/echevarria