Game Development Reference
It has to be noted that only IBM offered a complete, fixed virtual reality set: PC,
software programs and two behavioural interfaces - a head-mounted display and a
lever with location sensor. Not to our surprise, this product failed to appeal to buyers,
and is no longer marketed.
Another problem in creating custom interfaces is the division between the real
and virtual, as the device is “interfacing'' between these two worlds. For car driving
or airplane flying lessons, the simulator designers did not try creating virtual touch
sensations because of the difficulties mentioned earlier. They preferred associating the
real world (airplane cabin) with the virtual world (images and movements). This gives
a very custom and good-quality interface even if not everything is virtual! On the
other hand, if it is about studying the layout or the aesthetics of a car interior, it is
necessary to simulate a car interior. But where do you draw the line? (For example, the
steering can be real or virtual). Speaking of this position between real and virtual, we
were surprised to hear some people complain that a trolley, which helps to go about a
virtual shop, was real. Why do you want to, at any cost, simulate all objects virtually
just to complicate the creation? Therefore, it is necessary to correctly analyse the needs
of the application that you want to create.
2.3 “INSTRUMENTAL'' APPROACH FOR IMMERSION AND
2.3.1 Fundamental concepts of behavioural interfacing
Cognitive study of immersion and interaction in virtual environment is based on the
approach of the subject's activity . Man is at the heart of the system since the virtual
application is meant for him. It is the anthropocentric vision for the application user.
In the absolute sense, it is possible to schematise (Figure 2.5) man as being completely
immersed in an artificial world, the way he should perceive it as a user.
But for the VR application designer , this anthropocentric vision is not enough. He
must use this anthropocentric diagram, an objective to be achieved for the user, both
by splitting and completing it because it is necessary to finely analyse the interfacing
process and the devices to be designed. We will study behavioural interfacing using a
technocentric diagram. The designer must keep switching between an anthropocentric
approach and a technocentric approach to create an application in virtual reality.
Knowing and mastering this duality of virtual reality helps to better understand the
difficulties and the possible failures in making a human being become immersed and
interact in an artificial world. To have an in-depth understanding of this issue, we
have made a fundamental choice of analysing this process at three levels. You will
understand the pertinence of this choice as you further read this chapter. At first,
we can schematise the interface between man and the virtual world at the physical
level . In this case, we talk about sensorimotor immersion and interaction. We obtain
a “sensorimotor loop 1 '' between the subject and the computer. Disruptions caused by
latency and sensorimotor discrepancies should be as limited as possible.
1 Generally, a number of sensory methods are used. Therefore, we should rather use the plural,