NAG distributes (outside North America and Japan) the Template Graphics
range of software including:
-
low-level graphics libraries for PHIGS+ (GPHIGS and Figaro+), GL
(IRIS GL) and Open GL
-
'Two call' chart and graph libraries for Fortran and C, FIGraph
and PHIGure
-
a C++ class library for 3D graphics application development, Open
Inventor.
TGS are also working with Silicon Graphics on the WebSpace viewers for
VRML, the Virtual Reality Modelling Language, which provides the 3-D
extension to the World-Wide Web.
IRIS Explorer
IRIS Explorer is a scientific visualization system using a dataflow model
for operation and a drag-and-drop user interface. It provides an extensive
range of capabilities for reading, manipulating, sectioning and
visualizing complex data. However, IRIS Explorer is more than just a
scientific data visualization system, it is a comprehensive application
building system and prototyping framework. IRIS Explorer is now developed
and maintained within the UK directly by NAG.
IRIS Explorer has no intrinsic visualization capability, indeed, the
central framework only provides the capabilities of encapsulating user
code in modules, interconnecting modules into maps and controlling the
execution of those maps, potentially over a distributed, heterogeneous
network of machines. Note that the user code to be encapsulated in a
module can be in Fortran, C or C++ and access to the source is not
required.
The functionality of IRIS Explorer, as seen by the user, is provided by
the range of pre-built modules provided with the system. At present, the
only large-scale module suite available is targetted at data
visualization, hence IRIS Explorer's position in the software market.
However, it is possible to provide any other functionality within the IRIS
Explorer framework through defining new data structures (for which support
is provided) and associated modules. IRIS Explorer maps can also be
collapsed into a single interface application for delivery
to end users.
The IRIS Explorer visualization capabilities are built on top of the Open
Inventor geometry capabilities with rendering taking place via OpenGL.
There are many advantages to this, not least compatibility with VRML
through Open Inventor and the emerging range of convertors to the VRML
(and hence Open Inventor) format. Also, IRIS Explorer can exploit the
rich functionality of the Open Inventor / Open GL software - stereo
facilities for example.
The NAG Graphics and Visualization Portfolio
At first sight it may appear that NAG's portfolio of graphics and
visualization software is functionally rich but not wholly coherent.
However, there is a strong inter-relationship between the software systems
offered and good migration paths for current and future users.
For NAG's existing customers there is now a migration path from NAG
Graphics to the higher level and easier to use two-call graphics
libraries from TGS. The TGS products also provide support to C users and users
wishing to add some interaction to their programs or for whom the
post-production editing capabilities of FIGraph would be an advantage.
For users working at the two-call graphics level, NAG can offer the
higher level of abstraction provided by IRIS Explorer, where the users'
functional code can be embedded in one or more modules and the visualization
facilities are provided by IRIS Explorer. This approach allows greater
flexibility for less coding effort while still allowing the user
access to existing codes and libraries.
For graphical programmers, the same staged approach can be adopted.
Programmers working at the lower level of OpenGL programming may find that
moving to Open Inventor will greatly simplify their work, and Open
Inventor development can take place within IRIS Explorer. For this
progression there is a clear line of compatibility, Open Inventor is built
on top of OpenGL and IRIS Explorer uses Open Inventor. This hierarchy also
allows the IRIS Explorer developer to use increasing levels of
sophistication if required, expanding from use of the IRIS Explorer
geometry API to full Open Inventor and on to OpenGL.
So, by offering a range of capabilities from low level numerically
oriented libraries up through interactive visualization software and on to
general purpose 3-D graphical facilities NAG is aiming to support users
as their own needs vary.
NAG's Other Products and Future Directions
Of course, graphics and visualization are not always an end in themselves.
In most application areas the generation or analysis of the data is the
key to the success of the system. NAG is, of course, a supplier of
mathematical software for numerical processing (Fortran, C and other
libraries), statistical processing (Genstat and Glim), computational
algebra (AXIOM) and related requirements. The main advantage of this for
the user is that there is a single point of contact for many of the
elements that they require. If the user needs to use several techniques in
a single application then they come from the same place, with the
advantages of co-located developers and if the user experiences
difficulties integrating the parts they need, there is only one port of
call for help, not several. The graphics and visualization portfolio
described above has only just come together, but already NAG is seeking
to integrate the technologies with its other products. The first fruits
of this work appeared in IRIS Explorer Release 3 which included both NAG
Graphics software (for 2-D graphs) and improved numerical operation in
some modules thanks to NAG's numerical capabilities. Work is also
underway on putting Open Inventor into AXIOM and looking at providing
broad statistics capabilities within IRIS Explorer.
Conclusion
NAG has enhanced its range of graphical and visualization product
offerings to offer a number of capabilities, at different levels, to meet
a variety of user requirements. By providing a set of related products,
and by increasingly integrating the capabilities of each product, NAG is
seeking to offer an unparalleled range of facilities to the professional
user.
Robert Iles, NAG Ltd
infodesk@nag.co.uk
