Data Visualization

Data Visualization refers to the process of displaying photo-realistic models. The issues of efficient display of large, multi-modal data sets are addressed. Construction of multi-resolution, object-based scenes allow control of an object and its resolution separately from the others. This new description of the data allows the user to maintain a high level of interactivity with the data being displayed. For instance, a view-dependent display strategy can select the amount of data that is necessary to represent each object as a function of the user viewpoint; occluded objects can thus be ignored during display. The display strategy must allow selection of the multi-modal information associated with the geometry of the model. Data visualization requires research in:

Virtual Reality Displays

A walk-through environment is to be built to test system performance and to allow the user to display and manipulate large data sets. The display set-up allows user interaction with the data through input devices such as a track-ball or a cyber-glove. The user is immersed into a virtual environment where the data surrounds him/her. The user's needs are taken into account to make decisions concerning the amount of data to display.

Hardware, Object, and View Dependent Display

Efficient manipulation of models necessitates both displaying a detailed view and obtaining an overview. The detail of objects in the scene may reveal one very small radioactive barrel in the corner of a large room or a detail in a large flat object like an aircraft wing. The overview allows the user to perform fast selection of areas of interest and make decisions on the orientation of the model. Therefore, the minimum requirement for a walk-through environment is to maintain constant frame-rate and hardware dependent interactivity during display. A more complex display strategy is needed when displaying extremely large multi-modal scenes. An object-based scene, where the object resolutions can be controlled, allows resolution selection for each object according to hardware performance and the user's view location. During display, the system inputs the user's needs and the hardware performance is computed to select the appropriate resolution to be displayed.