Now showing items 21-40 of 40

    • Fast Rendering of General Ellipses 

      Fellner, Dieter W.; Helmberg, Christoph (Eurographics Association, 1991)
      Even though GKS did not include circles and, in a more general form, ellipses and elliptical arcs in the list of elementary graphics primitives, CGM settled this omission with its standardization in 1987. According to CGM ...
    • A constraint-based UIMS using graph unification 

      Samuel, J. F. (Eurographics Association, 1991)
      This paper describes an experimental UIMS developed to investigate methods of combining and reusing objects within a constraint-based system. A novel approach based on graph-unification facilitated the definition of composite ...
    • Shading with Area Light Sources 

      Tanaka, Toshimitsu; Takahashi, Tokiichiro (Eurographics Association, 1991)
      This paper derives a shading model for area light sources which covers both diffuse and specular reflection. The shading model assumes ideally diffuse polygonal light sources and uses Phong’s reflection model. The model ...
    • Constructive Cubes: CSG Evaluation For Display Using Discrete 3-D Scalar Data Sets 

      Breen, David E. (Eurographics Association, 1991)
      The algorithm presented in this paper converts a CSG model into a representation for interactive display on an engineering workstation. Called Constructive Cubes, the algorithm extends the standard CSG-point classification ...
    • Validity Issues for Modular Boundary Models 

      Bruzzone, Elisabetta; De Floriani, Leila (Eurographics Association, 1991)
      Modular boundary models are a class of solid models which describe a solid object as a collection of face-abutting object parts, called components. The Face-to-Face Composition (FFC) model is a specific model of this class, ...
    • Using temporal and spatial coherence for accelerating the calculation of animation sequences 

      Gröller, Eduard; Purgathofer, Werner (Eurographics Association, 1991)
      Ray tracing is a well known technique for generating realistic images. One of the major drawbacks of this approach are the extensive computational requirements for image calculation. When generating animation sequences ...
    • Configurable Representations in Feature-based Modelling 

      Falcidieno, B.; Giannini, F.; Porzia, C.; Spagnuolo, M. (Eurographics Association, 1991)
      A double description is proposed for the representation of a feature-based model which supports the distinction between form and functionality. This description consists of a primary representation in terms of geometric ...
    • A Testbed for Architectural Modeling 

      Hall, Roy; Bussan, Mimi; Georgiades, Priamos; Greenberg, Donald P. (Eurographics Association, 1991)
      This paper describes the philosophy and implementation of a modeling system that is easy to use yet addresses some of the difficulties of design. It does this by supporting concurrent schematic and geometric representations, ...
    • A DDA Octree Traversal Algorithm for Ray Tracing 

      Sung, Kelvin (Eurographics Association, 1991)
      A spatial traversal algorithm for ray tracing that combines the memory efficiency of an octree and the traversal speed of a uniform voxel space is described. A new octree representation is proposed and an implementation ...
    • Sampling and Anti-Aliasing of Discrete 3-D Volume Density Textures 

      Sakas, Georgios; Gerth, Matthias (Eurographics Association, 1991)
      In recent years, a number of techniques have been developed for rendering volume effects (haze, fog, smoke, clouds, etc.) in order to enhance reality in computer-generated imagery as well as to improve the performance of ...
    • Construction Techniques of Graphic, Direct-Manipulation User Interfaces 

      Preea, Wolfgang; Pornberger, Gustav; Sikora, Hermann (Eurographics Association, 1991)
      This paper deals with human-computer interaction in several ways. On the one hand it presents the roots of interactive, graphic user interfaces and how such interfaces are implemented on the abstraction level of programming ...
    • Refinement criteria for adaptive stochastic ray tracing of textures 

      van Walsum, Theo; van Nieuwenhuizen, Peter R.; Jansen, Frederik W. (Eurographics Association, 1991)
      Adaptive stochastic ray tracing is a rendering technique that generates high-quality anti-aliased images by sampling the image in a non-regular pattern that is adaptively refined. Image refinement can be guided by image ...
    • Low Sampling Densities using a psychovisual approach 

      Bouville, Christian; Tellier, Pierre; Bouatouch, Kadi (Eurographics Association, 1991)
      It has long been observed that the keenness of sight is lower for diagonal directions than for horizontal or vertical ones. This anisotropy of the human eye response can be exploited by using a non-orthogonal sampling ...
    • Liberation from Flatland: 3D Interaction Based on the Desktop Bat 

      Slater, Mel; Davison, Allan (Eurographics Association, 1991)
      A novel device for 3D interaction is introduced, the Desktop Bat. This device is an evolutionary development of a mouse. It is like a mouse in that it is used on a desktop, but provides 5 degrees of freedom since in ...
    • Discrepancy as a Quality Measure for Sample Distributions 

      Shirley, Peter (Eurographics Association, 1991)
      Discrepancy, a scalar measure of sample point equidistribution, is discussed in the context of Computer Graphics sampling problems. Several sampling strategies and their discrepancy characteristics are examined. The ...
    • Declarative Graphics And Dynamic Interaction 

      Johnson, C.W.; Harrison, M.D. (Eurographics Association, 1991)
      First order logic provides a means of integrating the specification and prototyping of interactive systems. It can describe graphical images in a declarative and order independent manner. It supports the definition of ...
    • Combining Volume Rendering with Line and Surface Rendering 

      Frühauf, Martin (Eurographics Association, 1991)
      Volume data is discrete sampled data in the three-dimensional space. Volume rendering is defined as volume visualization directly from volume primitives and not via surface primitives. Geometric objects are represented as ...
    • Continuation Methods for Approximating Isovalued Complex Surfaces 

      Zahlten, Cornelia; Jürgens, Hartmut (Eurographics Association, 1991)
      Basically there are two different approaches for rendering isovalued surfaces in 3D space: projection methods and surface reconstruction. We are discussing two algorithms of the second kind. Both use continuation methods ...
    • Colour Illustrations 

      - (Eurographics Association, 1991)
    • FACES: Facial Animation, Construction and Editing System 

      Patel, Manjula; Willis, Philip J. (Eurographics Association, 1991)
      The aim of the Facial Animation, Construction and Editing System (FACES) is to provide a software simulation of the human face. Attention has focused on the face as an important means of non-verbal communication. The ...