Theoretical Foundations of 3D-Metaphors

Introduction A 3D-metaphor explains the handling of a 3Doperation with a two dimensional input device. It consists of two parts: the metaphorical concept [8] that describes the structural mapping from the user's mental model into the human-computer interface, and the implementation that maps interface events into the three-dimensional mathematical model of the application. To facilitate establishing a mental model, the metaphorical concept relates to prior user experiences with three dimensions. Important examples of 3D-metaphors can be found in [1, 3, 12]. Even more are reported in [2, 4, 5, 6, 7, 13, 14, 15]. 2 Why are 3D-metaphors important? Current developments emphasize new input devices with higher degrees of freedom for interaction with three-dimensional graphics application. Nonetheless, two-dimensional devices like mice or digitizers in pen computers still possess several advantages: ffl<F26.0