Browsing by Author "Hutchinson, Norman"
Now showing 1 - 3 of 3
Results Per Page
Sort Options
- ItemMetadata onlyA new approach to industrial local computer networking(1982-03-01) Patten, Terry; Hutchinson, Norman; Unger, Brian WA unique local message node interface and its application to industrial environments is described. A typical application is the monitoring and control of manufacturing plant equipment located in several adjacent buildings. The approach can provide a low cost, high speed network which is highly reliable and adaptable to changing requirements. Currently, simple network configurations such as contention networks, stars, or rings are often used to avoid complicated message routing algorithms. In this paper, we solve the routing problem with a simple hardware mechanism which implements the "flooding" algorithm. This hardware mechanism acts as a universal local network node interface that can be used to construct high speed networks of arbitrary connectivity.
- ItemMetadata onlyUSING RECURSION TO DESCRIBE POLYGONAL SURFACES(1984-04-01) Wyvill, Brian; Liblong, Breen; Hutchinson, NormanWe describe a three dimensional graphics system called PG (Polygon Groper) and its use by artists for defining and viewing solid objects. A simple set of commands in PG are used to manipulate 3D models. The models are stored as a hierarchy of objects, where each object represents a geometrical transformation of another object or a primitive polygon. It has been found that a hierarchical structure provides a more powerful way of building and manipulating 3D objects than conventional linear structures. The object hierarchy also allows recursion to be used to describe pictures which are difficult or impossible to define in other graphics systems without considerable programming effort. Although any recursive process may be expressed iteratively, a certain class of pictures is more concisely defined and more easily visualised recursively. Many tools are available to aid the artist manufacture primitive objects. These tools generate the surface polygons to describe different solids. PG offers a number of alternative viewing algorithms. These provide the artist with successively higher quality images at the cost of correspondingly greater time for computation. PG is an integral part of the Graphicsland System, a film animation system under development at the University of Calgary.
- ItemMetadata onlyUSING RECURSION TO DESCRIBE POLYGONAL SURFACES(1982-12-01) Wyvill, Brian; Liblong, Breen; Hutchinson, NormanWe describe a three dimensional graphics editor called PG (Polygon Groper) and its use by artists for defining and viewing solid objects. A simple set of commands in PG are used to manipulate 3D models. The models are stored as a hierarchy of objects, where each object represents a geometrical transformation of another object or a primitive polygon. It has been found that a hierarchical structure provides a more powerful way of building and manipulating 3D objects than conventional linear structures. The object hierarchy also allows recursion to be used to describe pictures which are difficult or impossible to define in other graphics systems without considerable programming effort. Although any recursive process may be expressed iteratively, a certain class of pictures is more concisely defined and more easily visualised recursively. Many tools are available to aid the artist manufacture primitive objects. These tools generate the surface polygons to describe different solids. PG offers a number of alternative viewing algorithms, these provide the artist with successively higher quality images at the cost of correspondingly greater time for computation. PG is an integral part of the Graphicsland, a film animation system under development at the University of Calgary.