Kinds of animations
Of course, change over time can be viewed in many
different ways, hence conveyed by animations differing in
complexity. Perhaps the simplest movement is a path or
trajectory. This can be animated as the movement of a dot,
providing that the features of the moving object are not
relevant. Representing the speed and manner of the moving
object may require enriched animations. Sometimes what
needs to be conveyed is more complex than a path, for
example, the movement of parts of an object or system with
respect to each other. The movement or change of either a
path or a system may be in two or three dimensions. In
these cases, movement is of the object or system itself. In
other cases, the object or system may be stationary, and the
movement of the viewpoint of the observer, to show other
aspects of the object or system. The critical information to
be conveyed determines the form of the animation. But
whatever the form, in order to be effective, an animation
must be perceived and comprehended adequately. Clearly,
complexity challenges comprehension.