ERCIM Computer Graphics Network Workshop on Virtual Reality Modelling
Language
by David Duce
The
ERCIM Computer Graphics Network organised a workshop on Virtual
Reality Modelling Language (VRML) at the Coseners House, Abingdon, UK,
on 29-30 January 1997, attended by 22 researchers from academia and industry
from 6 European countries. The idea for the workshop came from the Steering
Committee of the ERCIM Computer Graphics Network in May 1996. It was felt
by the Steering Committee that a workshop was needed in order to formulate
a European view on VRML. VRML is described as 'a file format for describing
interactive 3D objects and worlds to be experienced on the World Wide Web',
the significance of VRML is that it gives the web a graphics and interaction
capability of significance to many application areas. Many ERCIM institutes
are using VRML and have VRML-related activities.
VRML 2.0 has been put forward for standardization to the ISO/IEC Committee
responsible for computer graphics and image processing (JTC1/SC24). A review
of the document took place in the autumn of 1996 and an Editing Meeting
to address the 500 comments raised took place in the USA in December 1996.
Several members of the ERCIM Computer Graphics Network were involved in
the preparation of these comments. Three major concerns identified in this
process were the suitability of VRML for use in visualization applications
and the use of VRML in multi-user worlds and the quality of the VRML document
itself. The ERCIM Workshop focused on the first two of these issues.
The meeting opened with an introduction to the background and aims of
the workshop, given by David Duce. Anthony Steed, from University College
London who was a member of the UK delegation to the ISO/IEC VRML Editing
Meeting gave an overview of the state of the VRML document within the standardization
process. Two talks were given by researchers from the University of Leeds,
introducing the topics of VRML in visualization and multi user worlds and
describing work in progress at Leeds in these areas. The meeting then split
into groups to address these two topics in more detail. At the close of
the workshop, reports were received from the two working groups and recommendations
to ERCIM were formulated.
The Multi User Virtual Worlds (MUVW) group was chaired by Michael Wilson,
Rutherford Appleton Laboratory.
The group took four documents as the basis for discussion:
- the VRML 2.0 specification
- appendices on JavaScript, Java and external authoring interfaces
- proposals before the VRML Consortium working group on MUVW (which add
layers on top of VRML 2.0)
- the proposal for Universal Avatars before the Avatar Working Group.
Many recommendations were made by the Working Group which will be fed
into the VRML Consortium Working Groups. These covered topics such as scope
of VRML, architectures for MUVW, efficiency/ communications issues, object
creation, consistency, persistence and portability.
The Visualization group was chaired by Klaus Kansy, GMD.
Examples of the use of VRML in visualization work at the University
of Leeds and British Telecom were presented. Starting from these examples
and a reference model for visualization the group addressed where and how
VRML can be useful in visualization and where the deficiencies are. The
major issues identified were the need to control where interpolation is
done (which implies the need to carry application data along with geometric
and colour data), the need for better colour model support, and the need
for better facilities to handle large data sets (for example some form
of lazy fetch). Support for volume visualization is also missing in VRML
2.0. Some support is provided for sound, but no support is provided for
either sound synthesis or acoustic properties. Both are required to support
sonification applications.
The closing plenary session received reports from the groups and formulated
recommendations. Apart from the technical recommendations outlined above,
there were recommendations that ERCIM should join the recently formed VRML
Consortium the VRML analogue of the WWW Consortium pass the
output of the MUVW group to the relevant VRML Consortium Working Groups
and seek to establish a new VRML Consortium Working Group in the visualization
area. Although the request to join the VRML Consortium did not find favour
with the ERCIM Executive Committee in the form in which it was presented,
I am hopeful that a way forward will be found to enable ERCIM to join the
VRML Consortium on an annual review basis.
Since the Executive Committee meeting took place, Dave Nadeau at the
San Diego Supercomputer Center has announced an Information Visualization
Working Group meeting to be held during the VRML 97 Conference and has
established a mailing list and repository (see http://www.sdsc.edu/vrml/
for more information). One of the discussion items for his workshop is
whether to create an Information Visualization Working Group in the VRML
Consortium! The results of our discussions have been fed to him. Membership
of the Consortium would put ERCIM in a much stronger position to contribute
European expertise to these developments. We live in hope!
The full report of the workshop has been published as ERCIM Research
Report 02/97-R049 and is available through the ERCIM web site at http://www.ercim.org/publication/technical_reports/.
Please contact:
David Duce - CLRC
Tel: +44 1235 44 55 11
E-mail: D.Duce@rl.ac.uk
