CRS4 Libro, Contributo in un libro

URI permanente per questa collection

https://hdl.handle.net/11050/56

Sfogliare

Mostra il contenuto di CRS4 Libro, Contributo in un libro per Subject "3D virtual tools"

Ora in mostra 1 - 3 di 3
  • Immagine di anteprima
    Item
    Three-dimensional reconstruction and visualization of the cerebral cortex in primates
    (Springer, 2001-05) Demelio, Sergio; Bettio, Fabio; Gobbetti, Enrico; Luppino, Giuseppe
    We present a prototype interactive application for the direct analysis in three dimensions of the cerebral cortex in primates. The paper provides an overview of the current prototype system and presents the techniques used for reconstructing the cortex shape from data derived from histological sections as well as for rendering it at interactive rates. Results are evaluated by discussing the analysis of the right hemisphere of the brain of a macaque monkey used for neuroanatomical tract-tracing experiments.
  • Immagine di anteprima
    Item
    VB2: an architecture for interaction in synthetic worlds
    (ACM, 1993) Gobbetti, Enrico; Balaguer, Jean-Francis
    This paper describes the VB2 architecture for the construction of three-dimensional interactive applications. The system's state and behavior are uniformly represented as a network of interrelated objects. Dynamic components are modeled by active variables, while multi-way relations are modeled by hierarchical constraints. Daemons are used to sequence between system states in reaction to changes in variable values. The constraint network is efficiently maintained by an incremental constraint solver based on an enhancement of SkyBlue. Multiple devices are used to interact with the synthetic world through the use of various interaction paradigms, including immersive environments with visual and audio feedback. Interaction techniques range from direct manipulation, to gestural input and three-dimensional virtual tools. Adaptive pattern recognition is used to increase input device expressiveness by enhancing sensor data with classification information. Virtual tools, which are encapsulations of visual appearance and behavior, present a selective view of manipulated models' information and offer an interaction metaphor to control it. Since virtual tools are first class objects, they can be assembled into more complex tools, much in the same way that simple tools are built on top of a modeling hierarchy. The architecture is currently being used to build a virtual reality animation system.
  • Immagine di anteprima
    Item
    Virtuality Builder II: on the topic of 3D interaction
    (1993) Gobbetti, Enrico; Balaguer, Jean-Francis
    Most of today's user interfaces for 3D graphics systems still predominantly use 2D widgets, even though current graphical hardware should make it possible to create applications in which the user directly manipulates aspects of three-dimensional synthetic worlds. The difficulties associated with achieving the key goal of immersion has led the research in virtual environments to concentrate far more on the development of new input and display devices than on higher-level techniques for 3D interaction. It is only recently that interaction with synthetic worlds has tried to go beyond straightforward interpretation of physical device data. The design space for 3D interaction tools and techniques remains mostly unexplored, while being far larger than in standard 2D applications. Moreover, as stated by Myers, "the only reliable way to generate quality interfaces is to test prototypes with users and modify the design based on their comments". The creation of complex interactive applications is an inherently iterative process that requires user interface tools, such as toolkits or frameworks. The lack of experience in 3D interfaces makes it extremely difficult to design 3D interface toolkits or frameworks. We believe that offering the possibility to rapidly prototype and test novel interaction techniques should be the primary goal of such tools. It is therefore more important for these tools to provide a wide range of interaction components, than to enforce a particular interface style. In this paper we present the Virtuality Builder II (VB2) framework developed at the Swiss Federal Institute of Technology for the construction of 3D interactive applications. First, we'll give an overview of the design concepts of VB2. Next, we'll concentrate on how users interact with dynamic models through direct manipulation, gestures, and virtual tools.