A geometric modeling and animation system for virtual reality

IRTUAL Reality (VR) immerses the user in a three-dimensional (3D) environment that can be actively interacted with and explored. Users are free to move about this environment under their own control, and to interact with any objects they find using natural hand gestures and other motions. While virtual reality holds great promise as a useful interaction style for 3D applications, the hardware and software technologies supporting it have not matured enough to realize this promise. One of the main software challenges is reducing the effort required to create good virtual environments. This involves designing both the geometry and behavior of objects appearing in the environment, plus the composition of environments based on these objects. The problem of virtual environment design is complicated by the fact that the user can freely interact with the objects, therefore, objects must be prepared to respond to these actions. An environment where the user can merely move amongst the objects, like a ghost, and not interact with them in any form is not very interesting. When the objects react, they must take into account the user's actions, and the other objects in the environment. For example, when the user kicks a ball, the ball must bounce off the other objects in the environment, and not just sail through them. Thus, objects can't have canned behaviors triggered by user actions, but must be able to respond to a wide range of events and circumstances.