Game Development Reference
Choice between IBS and metaphor for the cognitive process of interfacing and
Provision of the BSAs to help the subject in his behavioural interfacing.
This instrumental approach is based on an anthropocentric question which is specific to
the domain of virtual reality and which is based on the concept of behavioural interface.
The instrumental approach helps to analyse the reconfiguration of the activity linked
to the usage of this technology. An essential lesson to be learned from these works
and from those of the French-speaking school is that the instrument is a compromise
between the subject and “the object'' of his activity or his action (Rabardel, 1995).
Instead of choosing an approach based on the activity of the subject, some use
an approach that is more “communication'' oriented. We are not in favour of this
point of view because the purpose of virtual reality is to fundamentally suggest the
sensorimotor activities and not to be a communication tool. It is only in certain types
of VR applications such as the collaborative applications that the stress is on inter-
The beginning of the specifications of the VR system concerns the functional I 2 :It
is necessary to analyse which actions and which environments of the real environment
it is useful to retain in the virtual environment when the purpose of the VR device is
to simulate certain aspects of the real world. If the purpose of the device is to simulate
an imaginary world, the references to the real world are not necessary. In this second
case, the sensorimotor schemas of the subject could be diverted from their activities of
the real environment: for example, opening a door can symbolically mean establishing
communication with a person, creating a virtual metaphor which the user will need
to adopt. For the simulation of an imaginary world, the choice between the IBS or the
metaphors for the behavioural interfaces is thus more liberal: Which schemas can be
imported from the real environment into a virtual environment and which schemas will
be specifically created for the virtual environments? The imagination of the designers
is sought to create new immersions and interactions in an imaginary world.
What can we assure in practical terms without developing the issue of the subject's
presence ? Designers often pose the following question to the first users of a VR device:
“Are you (present) in the world that we simulate (implied as in the real world)''?
For example, the following questions could have been asked: “Are you (present)
in a shop?'', “Are you (present) on the railway tracks?''. This question is ambiguous.
The user finds himself in a dilemma: “I want to say yes to please the designer because I
have experienced the simulation (the copy) of a real world, but then I also want to say
no because I can feel that I am in a virtual world which is artificially constructed!'' The
question does not make any sense because the virtual is always detectable at the senso-
rimotor level. After an immersion in a virtual environment, it is inappropriate to ask
these types of questions to the VR device users. It is better to ask the following question:
“Is the behaviour of the subject in the virtual environment similar to that in the
real environment, in terms of the functional I 2 which one wishes to obtain?''
And the answer to this question is not easy to process by the designers. In most
cases, the user cannot answer by himself (for example: is your buying behaviour similar