DOCTORAATSPROEFSCHRIFT - EDM - UHasselt

1.2 Interaction, Interaction Techniques and Input Devices 17
from all of these areas and efficiently combine those into a single system. It
is exactly the combining of these different fields, that each on their own have
an impact on the end system and on the other parts that makes NVE systems
one of the most challenging research areas in computer science.
In this work, the emphasis lies on the interactions occurring in NVEs,
which is a crucial part that has often been overlooked, which is striking, as it
is an important part of the definitions of both VEs and NVEs.
1.2 Interaction, Interaction Techniques and Input
Devices
Interaction is a subject that has been widely studied in many areas and, as
a result, has different tailored meanings in various sciences. In sociology,
for example, interaction is defined as a dynamic, changing sequence of social
actions between individuals (or groups) who modify their actions and reactions
due to the actions by their interaction partner(s) 1 . In physics, an interaction
or force specifically refers to the action of one physical object upon another
resulting in potential energy - the physical objects under consideration may
range from point particles to quantum fields. A more general definition of
interaction states that interaction is a kind of action that occurs as two or
more objects have an effect upon one another 1 . [APA 07] on their part define
the term quite similarly as: a reciprocal action, effect, or influence.
The focus of this study is in the field of NVEs, therefore we adapt the
latter definition for our purposes as follows:
”A virtual interaction is an event occurring in a virtual environment
that has an impact on one or more objects in the virtual
world or on the world itself.”
By object, we mean any entity that is present in that virtual environment,
thus also including representations of human or AI controlled actors. We
deliberately leave out the specification of how and by whom this event is
triggered in order to remain as general as possible. In the remainder of this
work, if we discuss interaction, we mean these virtual interactions. In relation
to interaction, we must make a clear distinction between what we refer to
as interactions and interaction techniques, two terms that are too often used
incorrectly. Interaction techniques (ITs), also named interaction methods or
methodologies, are used to refer to the way that user input is mapped onto
1 Wikipedia - Interaction (http://en.wikipedia.org/wiki/Interaction)