bluuebunny/crossref_metadata_2025_split huggingface dataset:
Report on Dialogue Specification Tools
Authors: Green Mark 
Published: October 2007

SummaryIn this report we have presented some of the issues pertaining to the notations used in UIMSs. At the present time there are a small number of implemented UIMSs, so there is some experience to draw upon. This is the first workshop of this nature where there has been a significant number of participants with implementation experience. This experience seemed to raise more issues than it resolved. The conclusion that can be drawn from this is there is still a considerable amount of work to be done in notations for UIMSs.One of the major problems encountered by this working group was the inability to compare different UIMSs. The systems discussed in this group have been used to produce user interfaces for different application areas, with different interaction styles and requirements. This makes it very difficult to compare the ease of use (for the user interface designer), and the quality of the resulting user interface. This problem would be partially solved by constructing a standard set of user interface problems. Each of the UIMSs could be used to solve these problems, and the results used as a means of comparison. This set of problems could be viewed as a benchmark test for user interface management systems. Along with developing the problems, techniques for measuring ease of use and the quality of the user interface must also be developed.
Some Issues in Designing User Interfaces to 3D Raster Graphics
Authors: van Wijk J.J. , Jansen F.W. , Bronsvoort W.F. 
Published: October 2007

AbstractNow that raster graphics has become a common tool in CAD/CAM systems, animation and many other applications, the need has arisen for user interfaces to graphics packages for these new applications. On the basis of a typology of the users, an analysis is presented of some of the choices which have to be made in developing these interfaces.
A General‐Purpose Multi‐Microprocessor Raster Graphics Display System with Anti‐Aliasing
Authors: Piller Ernst 
Published: October 2007

AbstractThe raster graphics display system described represents a general purpose mini‐computer, specially for CAD applications. The system is based on a hierarchical asynchronous multiple microprocessor system. In practice this mini‐computer is extendable up to 15–20 workstations. On the workstations, different graphical and non‐graphical devices can be connected. The most interesting workstation is a raster graphics display device which was developed specially for the computer system described. This raster graphics display device contains a processor for the application program, two dedicated processors and two separate identical frame buffers, each of them containing one whole set of image data. Applying algorithms for anti‐aliasing, virtual pixel dislocation (intensity dislocation) and multi‐pixel‐overlappings with hidden line (surface) elimination the image readability and quality can be increased considerably. In particular the paper deals with an anti‐aliasing algorithm with a real‐time hardware realization.
Generating High Quality Pictures by Ray‐Tracing
Authors: Bouville C. , Brusq R. , Dubois J.L. , Marchal I. 
Published: October 2007

AbstractRay‐casting techniques provide a very general framework in which many problems can be solved in a much easier way than with conventional methods. This is particularly true for the illumination model when a high level of realism is required. Another interesting feature of ray‐casting is its ability to display a wide class of algebraic surfaces with a minimum of approximation. Both aspects are developed in this paper where a full lighting model, based on a theoretical approach, is presented. Then, an algorithm for the display of surfaces of revolution is described.Computation time is the major drawback of ray‐tracing. Special purpose parallel processors seem to offer a good price/performance ratio compared to the use of supercomputers.
Computers and Art
Authors: Smith B Reffin 
Published: October 2007

AbstractThe use of computers in art is not new: examples are given of past and present applications. Three categories are mentioned: computer as tool, as origin of concepts and metaphors, and as controller. The use of the computer in art gives rise to the idea of computing as representation‐ rather than just information‐processing. Thus the computer can be said to ‘belong’ to artists and designers, and can be seen as a qualitative device. It is argued that computing is ‘really’ an art or design activity, and that this has implications for art, design and computing.
Browsing High Definition Colour Pictures
Authors: Willis Philip , Milford David 
Published: October 2007

AbstractThe authors describe a method of presenting colour pictures which allows users to browse by panning and zooming. The pictures are seen as though on a 512 by 512 by 12 bit framestore, but are defined to 4096 by 4096. The implementation allows the entire picture to be seen in overview, with fine details averaged, or to be zoomed in upon with finer detail progressively revealed by a sequence of twofold linear magnifications. Further zooming, beyond the resolution of the picture data, automatically produces a conventional pixel replication effect. In addition, the picture may be panned vertically or horizontally.
Interference in Computer Graphics
Authors: Firby P.A. , Stone D.J. 
Published: October 2007

AbstractThe interference of superposed families of curves is considered, for various types of superposition available through computer graphics. It is shown that the use of interference of this type for illustration and experimentation in hydrodynamics, optics, and in certain other situations, is rather limited. To use the technique of superposition most effectively in these areas it is found to be necessary to eliminate the interference, and to use cine techniques.
Modelling Solids In Four Dimensions
Authors: Nicol C.J. 
Published: October 2007

AbstractMOSS4 is a proposed language extension which allows the creation of systems that model rigid solids in three dimensions and their movement over time, the fourth dimension. MOSS4 allows the creation of completely independent objects that execute in parallel and communicate using message passing. Each object contains a hierarchy of components which are related to each other via common coordinate spaces, and by joints and constraints. The user can create joint types plus the operations defined on them which then apply to the solid the joint is combined with. The system that MOSS4 generates can switch between realtime and stop‐frame modes dynamically, and the user can generate synchronisation points to ensure consistency between independently executing objects.
Overlap Operations and Raster Graphics
Authors: Thomas A.L. 
Published: October 2007

AbstractThis paper outlines the development of a volume and surfaces modelling system for use with raster graphic displays. The ideas are presented in a historical framework to make the reasoning behind the design decisions clear and to indicate the main influences which have guided the work. There are two outcomes of importance: a language form for defining volumes and surfaces; and hardware to convert this representation directly into a display. The hardware provides hidden‐line or hidden‐area removal as a display primitive which, in an appropriate implementation, can be fast enough to support a range of real‐time display applications. Linked to this hidden‐line, hidden‐area removal facility is an ability to provide interference tests for objects that are being moved around in a scene. Again there appears to be a hierarchy of applications ranging in complexity from interactive volume editing to robot control and vision systems. The new facilities complement existing point and line based display operations, on which most current displays' hardware is based. A good case is emerging for integrating the two approaches into a single hardware implementation for CAD workstations and for simulator display systems.
Text, Images and Graphics Management System for Editorial Environment*
Authors: Cavaliere S. , Fantini M. , Turtur A. 
Published: October 2007

AbstractThis paper describes the architecture of a system, a prototype of which is being developed by the authors at IBM Rome Scientific Centre, providing an interactive approach to the printing process, starting from the input of the basic components (images, texts and graphics) up to the definition and modification of page layout and finally to driving high resolution output devices. The system manages collections of pages, called “documents”; in turn each page is defined as a spatial composition of elementary boxes distributed on different levels. The main characteristics of the system architecture are interactivity, modularity and non‐procedurality (the user has only to describe “what” has to be done, rather “how” to do it).
Shading of Solid Voxel Models
Authors: Bright Stephen , Laflin Susan 
Published: October 2007

AbstractThe purpose of any technique for modelling structures is to store a representation of them, and to produce two dimensional images such that a viewer correctly perceives the three dimensional nature of the structures. There are many methods for including three‐dimensional visual cues in a two‐dimensional image, but probably the most important one is that of shading. The intensity of light at any point on the model depends mainly on the orientation of the surface at that point with respect to the direction of the light source. In solid voxel modelling this information has to be extracted from the model. The discretisation inherent to modelling techniques has to be allowed for if successful shading is to be achieved. This paper considers the problems caused by the discretisation in solid modelling and offers compression and interpolation techniques to reduce them.
Image Generation by Space Sweep
Authors: Müller H. 
Published: October 2007

AbstractA method of using spatial coherence in image generation by raytracing is presented. The idea is to trace a set of rays in parallel. This is carried out by space sweep. Space sweep consists of moving a plane through the object space. The rays intersected by the plane are organized into a dynamic data structure R for range searching. When an object is met by the sweeping plane, those rays intersecting the object are found by a range search with the object in R. Exact complexity bounds are given for this algorithm, as well as details to allow practical application of this approach in image operation.
Displaying Relevant Features of Protein Molecules
Authors: Poet Ron , Milner‐White E. James 
Published: October 2007

AbstractWe present a novel type of computer generated picture in which the positions of the main chain alpha carbon atoms are averaged and the different types of hydrogen bonds between main chain atoms are represented by lines of different colours and thicknesses joining the alpha‐carbon atoms. This allows various types of helices, beta‐sheets, beta‐bulges and turns to be visualized. One beta‐hairpin turn exhibits a structural feature at the loop end that has previously been described as a G1 beta‐bulge. It occurs in another protein by itself, and can thus be said to be a new sort of turn.
Beyond Hershey: A Representation of Fonts for Computer Graphics
Authors: Gossling T.H. 
Published: October 2007

AbstractHershey's “Repertory of Occidental Fonts” is well known in the field of computer graphics, as a set of character‐forms which is superior to the cruder representations used when space was at a premium. This paper gives a method of extending Hershey's format to include true curves, thus giving near typographical quality.
Graphics in Reservoir Simulation
Authors: Watkins Howard K. 
Published: October 2007

AbstractReservoir Simulation is used to manage underground oil reservoirs, and the potential cost savings associated with increased oil recovery are enormous. Because of the mathematical complexity of simulation it is necessary to use graphics to view the results. Graphics programs in this environment must be easy to use, and capable of producing images on a variety of machines and graphical devices. The paper looks at some of the problems involved.
UltraPaint: A New Approach to a Painting System
Authors: Watters Geoff , Willis Philip 
Published: October 2007

AbstractThe ideas underlying a Painting System being developed at the University of Bath are introduced. This differs from a conventional system in that ultra high definition pictures of upto 1 gigabyte may be created. We discuss approaches to implementing a number of standard paint program utilities in a form suited to our high definition method. Finally, we describe an algorithm for the rapid extrusion of brush strokes on a raster device.
RasterCalc: Calculus for Operations on Graphics Colour Rasters
Authors: van den Bos Jan 
Published: October 2007

AbstractAn extended model and calculus, called RasterCalc, is presented for operations on discrete graphics rasters, including their colour functions. The operations are separated into two main categories: operations on domains, and operations on colour functions. The operations are further classified as local and remote, depending on the correspondence between destination and source pixels. The new raster element or pixel can be a function of a single element from one or more rasters, a function of a small area from other rasters, or a function of entire rasters. Local operations have their main applications in computer graphics, while remote operations are more oriented towards image processing. A mathematically oriented notation is used to define and represent the operations included. RasterCalc has been implemented as a procedure package in Pascal, to be used on a powerful, yet expensive display. Recently a C version has been completed for a personal colour computer with a special chip for raster operations.The work reported in this paper is partially supplied by the Dutch Technical Sciences Foundation, under project number LWI 14.0130: “Facilities for raster graphics in programming languages”
Systolic Architecture for Boolean Operations on Polygons and Polyhedra
Authors: Krishnan D. , Patnaik L.M. 
Published: October 2007

AbstractIn Computer‐Aided Design applications there is often a need to compute the union, intersection and Merence of two polygons or polyhedra. The sequential algorithms for this problem are characterized by poor speed of response and large computational complexity. In order to remove these defects, an algorithm amenable to implementation on a parallel architecture is proposed. The parallel architecture designed is a systolic one which forms a dedicated subsystem to perform set‐theoretic operations on polygons. The improvement in speed gained by using the systolic array as compared to a uniprocessor has been evaluated using simulation techniques. Extensions of this architecture to perform the same operations on polyhedra are also discussed.
Logical Input Devices and Interaction
Authors: van Liere R. , ten Hagen P. J. W. 
Published: October 2007

AbstractThe logical input device model, as is adopted in the standardized graphics package GKS, has been an accepted basis for producing device‐independent graphics systems. However, when used in highly interactive graphical applications, the logical input device model does not provide sufficient support for a number of fundamental issues inherent to interaction. This paper reopens a discussion which questions the functionality provided by the logical input device model when brought in conjunction with interaction. In particular, the logical input device model does not support the notion of input/output symmetry.CR Categories: 1.3.4 [Computer graphics]: Graphics utilities‐ graphics packages; 1.3.6 [Computer graphics]: Methodology and techniques‐ device independence, interaction techniques
Architectures of Graphic Processors for Interactive 2D Graphics
Authors: Fontenier Guy , Gros Pascal 
Published: October 2007

AbstractInteractive 2‐D systems have benefited greatly from the improvements in 1C technology. Today, the trend is to relieve the host computer from low level tasks through increasing the graphic system's computational power. The introduction of video RAMs has solved the problem of contention for memory cycles between the display generator and the video refresh controller. The improvements in graphic controllers have led from the first fixed instructions controllers to today's third generation of programmable graphic processors, able to support computer graphic interface standards. This article will present this evolution, and focus on a 2‐D graphic processor designed at the Imagery, Instrumentation and Systems Laboratory, based on the separation of graphic generation and memory management functions.
Modelling Natural Branching Structures
Authors: Waite Kevin W. 
Published: October 2007

AbstractThis paper describes the work done in creating a computer program capable of modelling rooted trees and in particular the branching structures of botanical and bronchial trees. Simplicity of design and flexibility of use was achieved by generalising the program to handle any rooted branching structure with the particular form being dictated by various controlling parameters which can be modified via a direct manipulation interface. The program provides a graphical display of the resultant tree and leaf distribution. The open skeletal design allows the user to tailor the program to a particular model and to easily access data derived by the model.
Colour Raster Operations
Authors: Willis P. J. , Walters G. W. 
Published: October 2007

AbstractWe propose a form of three‐input BitBlt/RasterOp which is useful for pictures constructed in a colour‐mapped form as well as in true colour. The model used for this is that of a piece of potentially multicoloured paper on which the picture appears as ink marks. Computationally simple range testing operations can be applied to the source and destination regions to produce many useful effects, some of which we demonstrate. The resulting operations are primitives which can be used to construct more complex operations.
3D Images of Molecular Properties by Triangulation of Contour Lines
Authors: Roch Michel , Weber Jacques , Pellegrini Christian 
Published: October 2007

AbstractComputer programs have been developed to display molecular properties on a raster scan device, both as 2D colour‐filled contour maps and as 3D solid models. Starting from 2D contour values calculated in parallel molecular grids, a triangulation algorithm, based on the connection of contours lying in successive planes, is applied for generating 3D solid models displayed with Gouraud shading. These methods of presentation have proved to be very useful for demonstrating the main features of chemical bonding and molecular reactivity.
Polygon Triangulation Algorithm as a Powerful Core Processor of PLAN‐I
Authors: Chen Xiangping , Ying Daoning 
Published: October 2007

AbstractA concise, complete and reliable algorithm for triangulating an arbitrary polygon is presented as a powerful core processor of PLAN‐I (Production Layout Automation Nucleus) system1. A polygon with inner loops is converted into a non‐self‐intersecting polygon (NIP) through adding‘Bridge Edges'. A triangular splitting algorithm for NIP is described in detail and successfully implemented. The program is about 300 lines in FORTRAN‐77. Sweeping and local operations with respect to the triangular‐faceted boundary representation are designed with the algorithm to improve functions of solid modeling in PLAN‐I. The algorithm of triangulation can also be applied to Boolean operations and other issues.
Hidden Octree Node Removal as a Pipeline Process
Authors: Heal B.W. 
Published: October 2007

AbstractA processing pipeline solution to the generation and display of octree encoded 3‐D objects is described. Particular emphasis is given to an algorithm which removes that part a of linear octree code which describes parts of the object which are invisible from a prescribed viewing position. The scope of the algorithm is restricted to viewing directions which are parallel to the Cartesian axes and to orthogonal projections. The algorithm is specifically designed to operate as a single stage within a pipeline of processes.
A Parallel HW/SW Environment for Image Synthesis
Authors: Paoluzzi A. , Rosina M. , Scopigno R. 
Published: October 2007

AbstractIn designing graphical workstations for high‐level performance presentations of graphical models, the main goal nowadays is to perform some effective real‐time traversal and rendering of data. In this paper we present a reference model of parallel processing for graphics, taking into account the main aspects of colour rendering of solid hierarchical shapes; i.e., traversal of structures, hidden surfaces removal, shadow identification and light models. In particular, a parallel design of the main graphical algorithms is presented. Three abstract machines are proposed, designed respectively for data structure traversing, for depth ordering and shadows computation and finally for shape merging and screen processing. Such abstract machines, internally parallel, may be combined in various ways to define different physical architectures.CR Categories and Subject Descriptors: C.1.2 [Multiple Data Stream Architectures] MIMD Processors, Parallel Processors; 1.3.2 [Computer Graphics] Graphics Systems; 1.3.3 [Computer Graphics] Picture Generation ‐Display Algorithms, Viewing Algorithms; 1.3.7 [Computer Graphics] Three Dimensional Graphics and Realism ‐ Colour, Shading, Shadowing, Visible Line/Surface I Algorithms.
KAΔMOE: A Clausal Language for CAD MOdeling Systems with Morphological Constraints
Authors: Milanese Vitaliano 
Published: October 2007

AbstractA declarative language (KAΔMOE) for CAD‐CAM modeling is presented. The language is designed to protect topological models' constraints and guarantee their inheritance in complex entities built up from simpler ones. By itself, KAΔMOE behaves as an evolution of Prolog, which is integrated with primitives for modularization and for privatizing modeling structures so as to guarantee interfacing the language with relational or deductive Data Bases.
Modelling Clip: Some More Results
Authors: Hübl Josef , Herman Ivan 
Published: October 2007

AbstractThe modedling clip of the PHIGS ISO Standard is mathematically analysed. The most important result of this analysis is the fact that the projective image of a modding clip body (that is a not necessarily bounded convex body in space) is simply the union of two convex bodies. Furthermore, it will also be proved that in some cases one of these two bodies is empty. This fact makes the implementation of the modelling clip fairly straightforward and makes it also possible to use all already existing results on clipping against general convex bodies without change.
The Implementation of a 2D Convex Hull Algorithm Using Perturbation
Authors: Day A.M. 
Published: October 2007

AbstractThis paper discusses the problem of geometric degeneracies and outlines possible solutions when converting geometric algorithms into practice. It concentrates on the application of one of the suggested solutions, a perturbation technique, to a 2D convex hull program. An outline of the relevant theory and its conversion into practice is given. Experimental results are presented and discussed.