Science at the Speed of Thought - Ambient Intelligence for Scientific Discovery - page 7

viewed and manipulated in the IVE. Representation is an important component
for learning. The key to enabling scientists to quickly and easily visualize their
scientific data in an immersive environment is to develop useful tools to help
convert raw data to immersive data. We have designed our system to use our
own representations but also to take advantage of representations computed by
other packages. For these tasks, we have created a Glyph Toolbox to easily create
our own geometry, and we have built software to convert the output of other
packages to a form that can be displayed in the IVE.
Glyph Toolbox: The Glyph Toolbox is a set of programs to create and manipu-
late three-dimensional objects in a format readable by a variety of visualization
programs. Glyphs are visual symbols used to convey information based on ap-
pearance or position. Simple glyphs include bars on a bar chart and dots on a
statistical plot. The Glyph Toolbox is a set of three-dimensional glyphs both
complex and intuitive enough to convey information to a wide audience, while
simple enough to generate geometry from scientific data.
The purpose of the Glyph Toolbox Project is to build a collection of indi-
vidual Unix style command line programs. Each program accomplishes a single
task to create or manipulate geometry that can be used to build a polygon based
virtual environment. A series of individual UNIX style simple commands can be
combined to create objects, and then scale, color, rotate, and/or translate them
to a particular specification. The tools (command and filters) output an ASCII
based file that is machine and rendering independent. The actual display of the
ASCII files is handled by converting the output polygon file into a format suit-
able for display by a viewing program, such as DIVERSE/diversifly, VRML,
Open Inventor [23], etc.
The Glyph Toolbox has a wide range of applications. It has been used to
create traditional glyphs for displaying data, such as error bars, menu items, or
logos. More complex examples include transforming molecular data, i.e. positions
of atoms in a grid, into a three-dimensional display of a crystalline structure, as
in Fig. 3. Each atom is represented by a Glyph Toolbox sphere, scaled, colored,
and put in its proper place in the crystal.
SAVG Format and Converting Other Package Output: Currently under devel-
opment is another type of Performer-based file format, called the SAVG format
(named after our research group, the Scientific Applications and Visualization
Group). Unlike the Glyph Toolbox file format, which was developed to help cre-
ate original objects for visualization, the SAVG format was initially developed as
a conversion format to allow data from a variety of scientific modeling packages
to be used in our immersive visualization environment. The SAVG format has
been enhanced since its origin with features to solve issues with transparency,
lighting, and eciency, and has grown into a very robust format for our virtual
laboratory. Geometry can be defined using polygons, lines, points, and triangle
strips. Polygons can be converted into their corresponding wire frame objects,
or individually shrunk for better viewing. Examples of visualizations using the
SAVG format are shown below in Figs. 4 and 5, which demonstrate SAVG ca-
pabilities in transparency, as well as the shrinkage effect.