Graphic card technology like AGP and 3DFX enabled Schofield
business technology division to produce low cost, complex, virtual
reality solutions for the desktop PC
Introduction
The Schofield Lothian group offers construction management services
and has clients and employees in over 20 countries worldwide. The
company consists of several separate divisions focused on spatial
modelling, strategic planning and project management. One
department works extensively in creating comprehensive databases
for clients. These databases contain the associated paperwork,
designs and costing required for any large construction project. In
1996, the business technology teams at Schofield were charged with
creating a financially viable, virtual reality modelling service
for these clients. Until recently, the use of virtual reality
modelling was often seen as expensive and in need of highly
specialist video hardware. Simon Gardiner from the business
technology team at Schofield explains that: "At the start of this
work, our clients were reluctant to get involved in 3D modelling.
There was a perception among many that the technology required a
desktop virtual reality solution that just wasn't ready at that
time."
Accelerated graphics portThe team set up several
development systems running a wide variety of CAD tools. The
hardware was based on Pentium 2 technology and AGP graphics cards.
The Accelerated Graphics Port (AGP) in Pentium II processor systems
brings faster, enhanced graphics to the PC. While physically
similar to the existing PCI (Peripheral Components Interface) bus,
AGP offers improved performance. Application software, especially
3D graphics, exploits these performance increases by allocating and
managing memory appropriately. However, software without AGP
optimisations also benefits due to the support given to AGP via
Windows. With AGP-targeted applications, the 3D models have more
texture, more detail and higher screen resolution at increased
frame rates.Many powerful, yet low cost graphic accelerators
support AGP. Combined with the widespread adoption of standards
like OpenGL, this helped the business technology team achieve its
goal. To allow users to view the models they had created, model was
encoded each with a RealiMation tool from Datapath. The RealiMation
virtual reality system allows any user to walk around the virtual
world, in real-time, through a free viewer. This viewer is
optimised for Windows Direct Draw, OpenGL and 3DFX, giving it
compatibility with every major 3D accelerator running under
Windows.
3DFX - Not just for gamersAll personal computers
come pre-installed with a 2D graphics board designed primarily for
flat applications like Microsoft Word and Excel. To make 3D images
in real-time, a computer must make millions of complex mathematical
calculations every second. This can make 3D graphics applications
slow and jerky as the computer gets caught up rendering 3D images
in addition to running the program. 3D accelerators solve this
problem; the 3D graphics that were previously rendered by the CPU
are now rendered by the 3D accelerator. This significantly
increases performance, visual effects and drastically improves the
3D experience.
Breaking cultural barriersOne of Schofield's
recent clients has used this system to create presentations and
tenders tailored for overseas construction contracts. In one
particular case, a planned railway project was altered to assist a
Taiwanese client's understanding. This means that a virtual model
will have certain key features, like symbols and colour schemes,
altered according to which country the presentation is intended
for. This helps to break down language barriers and enables some
question to be answered visually.The use of video is also an
important aspect. Several of Schofield's development systems have
been upgraded with graphics cards that allow the "virtual walk
through" of a model to be converted to videotape. This is useful
for trade shows, presentations and client work.Gardiner explains
that: "The acceptance of windows and universal standards has made
our 3D virtual reality services much more user friendly. The next
generation of technology will enhance the quality of the images
that we can render in real-time."Although software like AEC AutoCAD
and Realimation plays a big part in this low cost virtual reality
solution, graphics card technology like AGP and 3DFX have allowed
Schofield's business technology division to produce complex,
virtual reality solutions for the desktop PC.
Will
Garside
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