Interactive Scene Walkthrough Using a Physically-Based Virtual Camera
Turner R, Gobbetti E, Balaguer JF, Thalmann D
Proc. CAAD Futures. 1991
Keywords
3D Interaction, Motion Control, Dynamics, Virtual Cameras
Abstract
One of the most powerful results of recent advances in graphics hardware
is the ability of a computer user to interactively explore a virtual buildin
gor landscape. The newest three-dimensional input devices, together with
high speed 3D graphics workstations, make it possible to view and move
through a 3D scene by interactively controlling the motion of a virtual
camera. In this paper, we describe how natural and intuitive control of
building walkthrough can be achieved by using a physically-based model
of the virtual camera's behavior. Using the laws of classical mechanics
to create and abstract physical model of the camera, we then simulate the
virtual camera motion in real time in response to force date from the various
3D input devices (e.g. the Spaceball and Polhemus 3Space Digitizer). The
resulting interactive behavior of the model is determined by several physical
parameters such as mass, moment of inertia, and various friction coefficients
which can all be varied interactively, and by constraints on the camera's
degrees of freedom. This allows us to explore a continuous range of physically-based
metaphors for controlling the camera motion. We present the results of
experiments using several of these metaphors for virtual camera motion
and describe the effects of the various physical parameters.
[PostScript]