DSpace Kolekce:
http://hdl.handle.net/11025/15421
2024-03-28T09:02:48ZPersistent Naming for Parametric Models
http://hdl.handle.net/11025/15485
Název: Persistent Naming for Parametric Models
Autoři: Agbodan, Dago; Marcheix, David; Pierra, Guy
Editoři: Skala, Václav
Abstrakt: Nowadays, many commercial CAD systems support history-based, constraint-based and feature-based modelling. The use of these new capabilities raises the issue of persistent naming which refers to the problem of identifying entities in an initial parametric model and matching them in the re-evaluated model. The goal of this paper in to propose a naming mechanism and an hierarchical structure enabling to identify topological entities and to apprehend the "design intent".2000-01-01T00:00:00ZAgbodan, DagoMarcheix, DavidPierra, GuyLaziness, a Way to Improve Distributed Computation of the Ray Tracing Algorithm
http://hdl.handle.net/11025/15484
Název: Laziness, a Way to Improve Distributed Computation of the Ray Tracing Algorithm
Autoři: Poitou, Olivier; Lecussan, Bernard; Bermes, Sébastien
Editoři: Skala, Václav
Abstrakt: This paper raises the issue of computational workload and memory load balancing to ray trace large scenes efficiently on a network of workstations. The task splitting is done on the image to be produced and not on the scene data to obtain a high performance level. To deal with the high memory requirements of such a distribution strategy, laziness is added to the base algorithm. This reduces the computing local memory requirements to the locally computed part of the image. It also reduces the sequential parts of the algorithm by making the voxelization process parallel. Many comparisons have been done using a manager/worker distribution algorithm on different scenes computed on a conventional network of workstations. Performance, load imbalance, communication overhead, and memory requirement results are given and discussed in this paper. Furthermore, this paper demonstrates that the proposed solution improves the results obtained with conventional algorithms, no matter what network used or however complex the image is.2000-01-01T00:00:00ZPoitou, OlivierLecussan, BernardBermes, SébastienReal-Time Virtual Cables Based on Kinematic Simulation
http://hdl.handle.net/11025/15483
Název: Real-Time Virtual Cables Based on Kinematic Simulation
Autoři: Hergenröther, Elke; Dähne, Patrick
Editoři: Skala, Václav
Abstrakt: We present an algorithm for the real-time simulation of virtual cables using inverse kinematics. A cable is
modeled by consecutive cylinder segments of equal size. The segments are connected by ball joints. At
every joint there is a spiral spring acting against the excursion of the joint. Given a start and an end
position of the cable, the algorithm calculates the shape of the cable that leads to minimal total energy.
The total energy is the sum of the potential energies of the segments and the elastic energies of the
springs. First, the algorithm calculates a cable with minimal total energy consisting of two segments. This
is taken as a starting basis for the computation of a cable consisting of four segments. At each following
step, the number of segments is doubled and a new shape of the cable is calculated based on the solution
of the previous step. The great advantage of this approach is the easy accommodation of the solution
exactness to the available computation time. If the user of the VR application is moving the cable, he gets
a fast but rough feedback. If he stops moving it, he/she gets an exact shape.2000-01-01T00:00:00ZHergenröther, ElkeDähne, PatrickComputer Graphics, Business and Education: Making the Connection
http://hdl.handle.net/11025/15482
Název: Computer Graphics, Business and Education: Making the Connection
Autoři: Bannatyne, Mark; Ross, William A.
Editoři: Skala, Václav
Abstrakt: Professional educators cannot be isolated in their professions as simply conveyers of information who direct curriculum materials toward their students. The fact is that within our profession teaching very often occupies the smallest portion of our workday. In an effort to maintain a high standard of technological excellence in our programs we are responsible for continually reviewing and updating curricula. Indeed, our instructional materials must reflect the high standards that business and industry will demand of our students once they graduate and enter the world of work. An effort must also be made to recruit and encourage the perpetuation of our field by actively seeking out students at the public school level as a means of guiding future scholars toward a career in computer graphics. All these efforts require concentrated efforts and plans that have been well thought out so our programs may continue to grow and prosper. An idle approach to recruiting and securing continual support from business and industry will sound the death knell for any computer graphics program regardless of how well its curriculum may be laid out.2000-01-01T00:00:00ZBannatyne, MarkRoss, William A.