Web-based 3D Graphics Rendering of Dynamic Deformation Structures
                 in Large-Scale Distributed Simulations

                           Donald P. Brutzman
                        Naval Postgraduate School
                         Monterey California USA
                            November 30, 2003

http://web.nps.navy.mil/~brutzman/DeformableSurfacesTechnicalReport2003November.pdf

This report examines multiple technologies, constraints and strategies
for Web-based 3D rendering of dynamic deformation structures in military
simulations. The motivating goal is to show how all manner of 3D objects
can be modeled, animated and manipulated, in a scalable and repeatable
fashion, in support of distributed large-scale virtual environments (LSVEs).
Such capabilities have broad training, analysis and operational value.

Web-based 3D graphics are the critical technology needed for rendering
the dynamic deformation of structures in distributed military simulations.
This is a broad subject area with many specific requirements.  The
Extensible 3D (X3D) Graphics standard undergoing ISO review includes
nearly the full range of capabilities needed. This approach differs from
other technical possibilities through adherence to an open standard,
royalty-free licensing for any use, availability of both commercial and
open-source implementations, provision for alternate software application
programming interfaces (APIs), multiple extensibility mechanisms, and a
growing content base of compatible 3D models.

Of particular importance is that X3D supports encoding of scenes using the
Extensible Markup Language (XML), which ensures that files are self-validating
and capable of reliable processing. Since XML is well suited to both Web
interchange and database interoperability, X3D using XML encodings provides
new capabilities for large-scale production.

Advanced X3D capabilities include geospatial referencing, humanoid animation,
shared-state distribution using the IEEE Distributed Interactive Simulation
(DIS) protocol, building prototypes, server-produced custom terrain, image
overlay of photographic, cartographic or pseudocolor images, integrated
physics for entity motion and sensor projection, a variety of user-interaction
techniques, and scalable loading/unloading of interrelated scenes.

The multiple challenges involved in modeling deformable surfaces cannot each
be solved in isolation. 3D graphics, underlying model representations and
networked distribution at first appear to be different topics. Nevertheless,
solutions for each area must simultaneously consider constraints and capabilities
of other areas. Compatible integration within a Web-based framework allows
effective use of deformable surfaces for diverse military simulations.
This report presents results emphasizing standards-based interoperability,
scalable architectures, demonstrated examples and directions for future work.