Browsing EG1989 Proceedings (Technical Papers) by Title

Now showing items 27-42 of 42

    • Ray Tracing Polynomial Tensor Product Surfaces 

      Giger, Christine (Eurographics Association, 1989)
      With regard to ray tracing algorithms for polynomial tensor product surfaces, the most timecritical step is to find an intersection point of a ray and a surface. In this case it proves to be very difficult to decide whether ...

    • A Reference Model for the Visualisation of Multi-Dimensional Data 

      Bergeron, R. Daniel; Grinstein, Georges G. (Eurographics Association, 1989)
      This paper presents a reference model for the development of systems for the visualization of multidimensional data. The purpose of the reference model is to build a conceptual basis for thinking about multi-dimensional ...

    • Representing Tolerance Information in Feature-Based Solid Modelling 

      Falcidieno, Bianca; Fossati, Bruno (Eurographics Association, 1989)
      In this paper a system for defining dimensions and tolerances is presented which deals with the geometric representation of the objects in a coherent and compact way. This model is a combination of a hierarchical boundary ...

    • The Structure of Tube - A Tool for Implementing Advanced User Interfaces 

      Hill, Ralph D.; Herrmann, Marc (Eurographics Association, 1989)
      Good user interfaces are very costly to implement and maintain. As user interfaces become more advanced, moving to various forms of direct manipulation, they become even more expensive and difficult to implement. In the ...

    • Subdivisions of Surfaces and Generalized Maps 

      Lienhardt, Pascal (Eurographics Association, 1989)
      The modeling of subdivisions of surfaces is of greatest interest in Geometric Modeling (in particular for Boundary Representation) , and many works deal with the definition of models, which enable the representation of ...

    • Supporting Graphical Languages with Structure Editors 

      Szwillus, Gerd (Eurographics Association, 1989)
      Graphical editors are used in numerous application fields for purposes like specification, design, modelling, or description of structures of various kinds. These editors handle the graphical representations based on objects ...

    • A Topological Map-Based Kernel for Polyhedron Modelers: Algebraic Specification and Logic Prototyping 

      Dufourd, Jean-Francois (Eurographics Association, 1989)
      This paper deals with the topology of surfaces, in the boundary representation of three dimensional objects. Orientable, not orientable, closed or open surfaces are efficiently described and handled when considered as ...

    • Toward Realistic Formal Specifications for Non-Trivial Graphical Objects 

      Fiume, Eugene (Eurographics Association, 1989)
      Formal specification has long been advocated in programming methodology, and is becoming increasingly popular in computer graphics to characterise the semantics of components of graphics systems. Unfortunately, formal ...

    • Two Object-Oriented Models to Design Graphical User Interfaces 

      Hübner, Wolfgang; Gomes, Mario Rui (Eurographics Association, 1989)
      Object-oriented concepts are well-suited to deal with the characteristics of user interfaces. Up to now several attempts to integrate the object-oriented paradigm in user interface models were evolved and led to distinctive ...

    • The Use of Finite Element Theory for Simulating Object and Human Body Deformations and Contacts 

      Gourret, Jean-Paul; Magnenat-Thalmann, Nadia; Thalmann, Daniel (Eurographics Association, 1989)
      This paper presents a method for combining image synthesis and modeling based on a finite element method (FEM) to get realistic intelligent images. FEM is used for modeling both elastically and plastically deformations of ...

    • Variations on a Dither Algorithm 

      Pins, Markus; Hild, Hermann (Eurographics Association, 1989)
      Mapping continuous-tone pictures into digital halftone pictures, i.e. 0/1-pictures, for printing purposes is a well explored technique. In this paper, one of these algorithms, the two-dimensional error-diffusion algorithm ...

    • Visualisation in Astrophysics 

      Ertl, T.; Geyer, F.; Herold, H.; Kraus, U.; Niemeier, R.; Nollert, H.- P.; Rebetzky, A.; Ruder, H.; Zeller, G. (Eurographics Association, 1989)
      This paper reports on progress we have made in modelling cosmic X-ray sources on supercomputers. The results we present are meant to serve as an example for the fact that sophisticated visualization techniques play a crucial ...

    • Visualisation of Digital Terrain Data 

      Thiemann, Rolf; Fischer, Joachim; Haschek, Guido; Kneidl, Gerald (Eurographics Association, 1989)
      Visualisation technology has found practical application in the field of terrain data processing. A raster data base (RDB-) concept will be introduced, i.e. a multi-dimensional concept of terrain data using elevation data, ...

    • Visualizing Curvature Discontinuities of Free-Form Surfaces 

      Pottmann, Helmut (Eurographics Association, 1989)
      A new method for the visualization of curvature discontinuities of free-form surfaces is presented. It is based upon an improvement and refinement of the well-known technique of displaying isophotes.

    • A VLSI Chip for Ray Tracing Bicubic Patches 

      Bouatouch, Kadi; Saouter, Yannick; Candela, Jean Charles (Eurographics Association, 1989)
      This paper deals with the integration of a VLSI chip dedicated to ray tracing bicubic patches. A recursive subdivision algorithm is embedded in this chip. The recursion stops when the termination conditions are met. A ...

    • When is a Line a Line? 

      Brodlie, Ken W.; Göbel, Martin; Roberts, Ann; Ziegler, Rolf (Eurographics Association, 1989)
      Conformance testing of graphics systems is a very complex and exhausting task. Years of practice with the GKS testing tools have shown a need for the automatic testing of visual output. Indeed, with regard to graphics ...