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CumInCAD is a Cumulative Index about publications in Computer Aided Architectural Design
supported by the sibling associations ACADIA, CAADRIA, eCAADe, SIGraDi, ASCAAD and CAAD futures

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_id	c6a9
authors	Kay, Douglas Scott and Greenberg, Donald P.
year	1979
title	Transparency for Computer Synthesized Images
source	SIGGRAPH '79 Conference Proceedings. August, 1979. vol. 13 ; no. 2: pp. 158-164 : ill. (some col.). includes bibliography
summary	Simple transparency algorithms which assume a linear transparency over an entire surface are the type most often employed to produce computer synthesized images of transparent objects with curved surfaces. Although most of the images created with these algorithms do give the impression of transparency, they usually do not look realistic. One of the most serious problems is that the intensity of the light that is transmitted through the objects is generally not proportional to the amount of material through which it must pass. Another problem is that the image seen behind the objects is not distorted as would naturally occur when the light is refracted as it passes through a material of different density. Use of a non-linear transparency algorithm can provide a great improvement in the realism of an image at a small additional cost. Making the transparency proportional to the normal to the surface causes it to decrease towards the edges of the surface where the path of the light through the object is longer. The exact simulation of refraction, however, requires that each sight ray be individually traced from the observer, through the picture plane and through each transparent object until an opaque surface is intersected. Since the direction of the ray would change as each material of differing optical density was entered, the hidden surface calculations required would be very time consuming. However, if a few assumptions are made about the geometry of each object and about the conditions under which they are viewed, a much simpler algorithm can be used to approximate the refractive effect. This method proceeds in a back-to-front order, mapping the current background image onto the next surface, until all surfaces have been considered
keywords	computer graphics, shading, transformation, display, visualization, algorithms, realism
series	CADline
last changed	2003/06/02 13:58

_id	ga0015
id	ga0015
authors	Daru, R., Vreedenburgh, E. and Scha, R.
year	2000
title	Architectural Innovation as an evolutionary process
source	International Conference on Generative Art
summary	Traditionally in art and architectural history, innovation is treated as a history of ideas of individuals (pioneers), movements and schools. The monograph is in that context one of the most used forms of scientific exercise. History of architecture is then mostly seen as a succession of dominant architectural paradigms imposed by great architectural creators fighting at the beginning against mainstream establishment until they themselves come to be recognised. However, there have been attempts to place architectural innovation and creativity in an evolutionary perspective. Charles Jencks for example, has described the evolution of architectural and art movements according to a diagram inspired by ecological models. Philip Steadman, in his book "The Evolution of Designs. Biological analogy in architecture and the applied arts" (1979), sketches the history of various biological analogies and their impact on architectural theory: the organic, classificatory, anatomical, ecological and Darwinian or evolutionary analogies. This last analogy "explains the design of useful objects and buildings, particularly in primitive society and in the craft tradition, in terms of a sequence of repeated copyings (corresponding to inheritance), with small changes made at each stage ('variations'), which are then subjected to a testing process when the object is put into use ('selection')." However, Steadman has confined his study to a literature survey as the basis of a history of ideas. Since this pioneering work, new developments like Dawkins' concept of memes allow further steps in the field of cultural evolution of architectural innovation. The application of the concept of memes to architectural design has been put forward in a preceding "Generative Art" conference (Daru, 1999), showing its application in a pilot study on the analysis of projects of and by architectural students. This first empirical study is now followed by a study of 'real life' architectural practice. The case taken has a double implication for the evolutionary analogy. It takes a specific architectural innovative concept as a 'meme' and develops the analysis of the trajectory of this meme in the individual context of the designer and at large. At the same time, the architect involved (Eric Vreedenburgh, Archipel Ontwerpers) is knowledgeable about the theory of memetic evolution and is applying a computer tool (called 'Artificial') together with Remko Scha, the authoring computer scientist of the program who collaborates frequently with artists and architects. This case study (the penthouse in Dutch town planning and the application of 'Artificial') shall be discussed in the paper as presented. The theoretical and methodological problems of various models of diffusion of memes shall be discussed and a preliminary model shall be presented as a framework to account for not only Darwinian but also Lamarckian processes, and for individual as well as collective transmission, consumption and creative transformation of memes.
keywords	evolutionary design, architectural innovation, memetic diffusion, CAAD, penthouses, Dutch design, creativity, Darwinian and Lamarckian processes
series	other
more	http://www.generativeart.com/
last changed	2003/08/07 17:25

_id	4517
authors	Fuchs, Henry, Kedem, Zvi M. and Naylor, Bruce F.
year	1979
title	Predetermining Visibility Priority in 3-D Scenes
source	SIGGRAPH '79 Conference Proceedings. August, 1979. vol. 13 ; no. 2: pp. 175-181 : ill. includes bibliography
summary	The principal calculation performed by all visible surface algorithms is the determination of the visible polygon at each pixel in the image. Of the many possible speedups and efficiencies found for this problem, only one published algorithm (developed almost a decade ago by a group at General Electric) took advantage of an observation that many visibility calculations could be performed without knowledge of the eventual viewing position and orientation -- once for all possible images. The method is based on a 'potential obscuration' relation between polygons in the simulated environment. Unfortunately, the method worked only for certain objects; unmanageable objects had to be manually (and expertly!) subdivided into manageable pieces. Described in this paper is a solution to this problem which allows substantial a-priori visibility determination for all possible objects without any manual intervention. The method also identifies the (hopefully, few) visibility calculations which remain to be performed after the viewing position is specified. Also discussed is the development of still stronger solutions which could further reduce the number of these visibility calculations remaining at image generation time
keywords	algorithms, hidden lines, hidden surfaces, computer graphics
series	CADline
last changed	2003/06/02 13:58

_id	cebc
authors	Rhodes, Michael L.
year	1979
title	An Algorithmic Approach to Controlling Search in Three-Dimensional Image Data
source	SIGGRAPH '79 Conference Proceedings. August, 1979. vol. 13 ; no. 2: pp. 134- 141 : ill. includes bibliography
summary	In many three-dimensional imaging applications random shaped objects, reconstructed from serial sections, are isolated to display their overall structure in a single view. This paper presents an algorithm to control an ordered search strategy for locating all contours of random shaped objects intersected by a series of cross-section image planes. Classic search techniques in AI problem solving and software for image processing and computer graphics are combined here to aid program initialization and automate the search process thereafter. Using three-dimensional region growing, this method isolates all spatially connected pixels forming a structure's volume and enters image planes the least number of times to do so. An algorithmic description is given to generalize the process for controlling search in 3-D image data where little core memory is available. Phantom and medical computer tomographic data are used to illustrate the algorithm's performance
keywords	algorithms, AI, image processing, computer graphics, methods, search
series	CADline
last changed	2003/06/02 10:24

_id	4240
authors	Winograd, Terry
year	1979
title	Beyond Programming Languages
source	Communications of the ACM. July 1979. Vol. 22: pp. 391-401. includes bibliography
summary	As computer technology matures, our growing ability to create large systems is leading to basic changes in the nature of programming. Current programming language concepts will not be adequate for building and maintaining systems of the complexity called for by the tasks we attempt. Just as high level languages enabled the programmer to escape from the intricacies of a machine's order code, higher level programming systems can provide the means to understand and manipulate complex systems and components. In order to develop such systems, attention needs to be shifted away from the detailed specification of algorithms, towards the description of the properties of the package and objects with which we build. This paper analyzes some of the shortcomings of programming languages as they now exist, and lays out some possible directions for future research
keywords	programming, languages, systems,
series	CADline
last changed	1999/02/12 15:10

_id	fcd6
authors	Berger, S.R.
year	1979
title	Artificial Intelligence and its impact on Coimputer-Aided Design
source	Design Studies, vol 1, no. 3
summary	This paper provides, for readers unfamiliar with the field, an introductory account of research which has been carried out in artificial intelligence. It attempts to distingussh between an artificial intelligence and a conventional computing approach and to assess the future influence of the former on computer-aided design.
series	journal paper
last changed	2003/04/23 15:14

_id	af53
authors	Boyer, E. and Mitgang, L.
year	1996
title	Building community: a new future for architecture education and practice
source	Carnegie Foundation for the Advancement of Teaching
summary	Internships, before and after graduation, are the most essential link connecting students to the world of practice. Yet, by all accounts, internship is perhaps the most troubled phase of the continuing education of architects. During this century, as architectural knowledge grew more complex, the apprenticeship system withered away and schools assumed much of the responsibility for preparing architects for practice. However, schools cannot do the whole job. It is widely acknowledged that certain kinds of technical and practical knowledge are best learned in the workplace itself, under the guidance of experienced professionals. All state accrediting boards require a minimum period of internship-usually about three years-before a person is eligible to take the licensing exam. The National Council of Architectural Registration Boards (NCARB) allows students to earn up to two years of work credit prior to acquisition of an accredited degree. The Intern Development Program (IDP), launched by NCARB and the American Institute of Architects in 1979, provides the framework for internship in some forty states. The program was designed to assure that interns receive adequate mentoring, that experiences are well-documented, and that employers and interns allocate enough time to a range of educational and vocational experiences to prepare students for eventual licensure. As the IDP Guidelines state, "The shift from school to office is not a transition from theory to pragmatism. It is a period when theory merges with pragmatism.... It's a time when you: apply your formal education to the daily realities of architectural practice; acquire comprehensive experience in basic practice areas; explore specialized areas of practice; develop professional judgment; continue your formal education in architecture; and refine your career goals." Whatever its accomplishments, however, we found broad consensus that the Intern Development Program has not, by itself, solved the problems of internship. Though we found mutually satisfying internship programs at several of the firms we visited or heard about around the country, at many others interns told us they were not receiving the continuing education and experience they needed. The truth is that architecture has serious, unsolved problems compared with other fields when it comes to supplying on-the-job learning experiences to induct students into the profession on a massive scale. Medicine has teaching hospitals. Beginning teachers work in actual classrooms, supported by school taxes. Law offices are, for the most part, in a better financial position to support young lawyers and pay them living wages. The architecture profession, by contrast, must support a required system of internship prior to licensure in an industry that has neither the financial resources of law or medicine, the stability and public support of teaching, nor a network of locations like hospitals or schools where education and practice can be seamlessly connected. And many employers acknowledged those problems. "The profession has all but undermined the traditional relationship between the profession and the academy," said Neil Frankel, FAIA, executive vice president of Perkins & Will, a multinational firm with offices in New York, Chicago, Washington, and London. "Historically, until the advent of the computer, the profession said, 'Okay, go to school, then we in the profession will teach you what the real world is like.' With the coming of the computer, the profession needed a skill that students had, and has left behind the other responsibilities." One intern told us she had been stuck for months doing relatively menial tasks such as toilet elevations. Another intern at a medium-sized firm told us he had been working sixty to seventy hours per week for a year and a half. "Then my wife had a baby and I 'slacked off' to fifty hours. The partner called me in and I got called on the carpet for not working hard enough." "The whole process of internship is being outmoded by economics," one frustrated intern told us. "There's not the time or the money. There's no conception of people being groomed for careers. The younger staff are chosen for their value as productive workers." "We just don't have the best structure here to use an intern's abilities to their best," said a Mississippi architect. "The people who come out of school are really problems. I lost patience with one intern who was demanding that I switch him to another section so that he could learn what he needed for his IDP. I told him, 'It's not my job to teach you. You are here to produce.'" What steps might help students gain more satisfying work opportunities, both during and after graduation?
series	other
last changed	2003/04/23 15:14

_id	819a
authors	Brassel, Kurt E. and Fegeas, Robin
year	1979
title	An Algorithm for Shading of Regions on Vector Display Devices
source	SIGGRAPH '79 Conference Proceedings. August, 1979. vol. 13 ; no. 2: pp. 126- 133 : ill. includes bibliography
summary	The display of shaded polygons by line, cross-hatch, and dot patterns on vector devices is a task frequently used in computer graphics and computer cartography. In applications such as the production of shaded maps polygon shading turns out to be critical with respect to time requirements, and the development of efficient algorithms is of importance. Given an arbitrary polygon in the plane without self-crossing edges (simply-connected polygon), the task at hand is to shade this polygon with one or two sets of parallel lines where for each set a shading angle and a line distance are given. The basic concept of this new algorithm is to decompose the polygon into a set of mutually exclusive trapezoids (in special cases triangles) where the parallel edges of the trioxides are parallel to the desired shading lines. These trapezoids and triangles are then shaded in a fast procedure. In its present form the algorithm handles regions with up to 300 islands. Possible extensions include the construction of dash and cross patterns
keywords	algorithms, polygons, software, computer graphics, shading, GIS, mapping, drafting, information
series	CADline
last changed	2003/06/02 13:58

_id	6d0b
authors	Brown, Bruce Eric
year	1979
title	Computer Graphics for Large Scale Two- and Three-Dimensional Analysis of Complex Geometries
source	SIGGRAPH '79 Conference Proceedings. August, 1979. vol. 13 ; no. 2: pp. 33-40 : ill. includes bibliography
summary	A comprehensive set of programs have been developed for analysis of complex two- and three- dimensional geometries. State of the art finite element and hydrodynamic codes are being used for the analytical portion of the work. Several additional codes depending heavily on graphics have been developed to assist the analytical effort. These are basically used for the pre- and post-processing of the data. Prior to running any analysis, the geometry of the body of interest must be represented in the form of small 'finite elements.' After the analysis is run, the data must be post-processed. Both spatial and temporal data exist in the database. It is the database between the analysis codes and the post- processors which allows a wide variety of analysis codes to use the same post-processors. The temporal plotting codes produce time histories for specified quantities (i.e. temperature, pressure, velocity, stress, etc.) at various locations within the body. They may also produce cross-plots of these variables (i.e. stress vs. strain at a particular position). One of the two codes used for plotting of the spatial data is for two-dimensional geometries and the other for three-dimensional models. For three dimensions, the Watkins' hidden surface / line processor is utilized for plots. The spatial plotters display contour lines on vector output devices and color fringes (or gray values) on raster output devices. They both may also display deformed geometries. Further the three-dimensional code has extensive animation capabilities for movie productions
keywords	computer graphics, finite elements, modeling, engineering, database, animation, mechanical engineering
series	CADline
last changed	1999/02/12 15:07

_id	4eb9
authors	Brown, Kevin Q.
year	1979
title	Dynamic Programming in Computer Science
source	44 p. : ill. Pittsburgh, PA: Department of Computer Science, CMU, February, 1979. CMU-CS-79-106. Includes bibliography
summary	This paper is a survey of dynamic programming algorithms for problems in computer science. For each of the problems the author derives the functional equations and provides numerous references to related results. For many of the problems a dynamic programming algorithm is explicitly given. In addition, the author presents several new problems and results
keywords	algorithms, problem solving, dynamic programming
series	CADline
last changed	2003/06/02 10:24

_id	22ce
authors	Cahn, Deborah U., Johnston, Nancy E. and Johnston, William E.
year	1977
title	A Response to the 1977 GSPC Core Graphic System
source	SIGGRAPH '79 Conference Proceedings. August, 1979. vol. 13 ; no. 2: pp. 57-62. includes bibliography
summary	This paper responds to the 1977 Core Graphics System of SIGGRAPH's Graphics Standards Planning Committee (GSPC). The authors are interested in low-level device-independent graphics for applications doing data representation and annotation. The level structure and bias in the core system toward display list processor graphics are criticized. Specific issues discussed include display contexts, attributes, current position, 3-dimensional graphics, area filling, and graphics input
keywords	computer graphics, standards
series	CADline
last changed	2003/06/02 13:58

_id	e7b8
authors	Dahl, Veronica
year	1983
title	Logic Programming as a Representation of Knowledge
source	IEEE Computer. IEEE Computer Society, October, 1983. vol. 16: pp. 106-110 : ill. includes bibliography
summary	Logic has traditionally provided a firm conceptual framework for representing knowledge. As it can formally deal with the notion of logical consequence, the introduction of Prolog has made it possible to represent knowledge in terms of logic and also to expect appropriate inferences to be drawn from it automatically. This article illustrates and explores these ideas with respect to two central representational issues: problem solving knowledge and database knowledge. The technical aspects of both subjects have been covered elsewhere (Kowalski, R. Logic for problem solving, North- Holland pub. 1979 ; Dahl, V. on database system development through logic ACM Trans.vol.7/no.3/Mar.1982 pp.102). This explanation uses simple, nontechnical terms
keywords	PROLOG, knowledge, representation, logic, programming, problem solving, database
series	CADline
last changed	1999/02/12 15:08

_id	c949
authors	Even, Simon
year	1979
title	Graph Algorithms
source	ix, 249 p. : ill. Potomac, MD: Computer Science Press Inc., 1979. includes bibliography and index -- (computer software Engineering series)
summary	The recent progress concerning efficient algorithms for graph processing and graph theory. Each chapter has a set of exercises, which makes it a text book
keywords	algorithms, graphs, theory
series	CADline
last changed	1999/02/12 15:08

_id	e83f
authors	Foley, James D., Templeman, James N. and Dastyar, Dara
year	1979
title	Some Raster Graphics Extensions to the Core System
source	SIGGRAPH '79 Conference Proceedings. August, 1979. vol. 13 ; no. 2: pp. 15-24 : ill. includes bibliography
summary	The Core System is a proposed standard subroutine package for line-drawing graphics. Some Core System extensions are presented for use with raster graphics equipment. The extensions, which are upward-compatible with the present Core System, provide filled polygons, display of arrays of pixels, use of a color look-up table, and hidden-surface on hidden- edge removal. The extensions are being integrated into an existing Core System implementation
keywords	hardware, computer graphics, standards,
series	CADline
last changed	2003/06/02 13:58

_id	eb8e
authors	Fowler, Robert J. and Little, James J.
year	1979
title	Automatic Extraction of Irregular Network Digital Terrain Models
source	SIGGRAPH '79 Conference Proceedings. August, 1979. vol. 13 ; no. 2: pp. 199- 207 : ill. includes bibliography
summary	For representation of terrain, an efficient alternative to dense grids is the Triangulated Irregular Network (TIN), which represents a surface as a set of non-overlapping contiguous triangular facets, of irregular size and shape. The source of digital terrain data is increasingly dense raster models produced by automated orthophoto machines or by direct sensors such as synthetic aperture radar. A method is described for automatically extracting a TIN model from dense raster data. An initial approximation is constructed by automatically triangulating a set of feature points derived from the raster model. The method works by local incremental refinement of this model by the addition of new points until a uniform approximation of specified tolerance is obtained. Empirical results show that substantial savings in storage can be obtained
keywords	GIS, mapping, computational geometry, data structures, mapping, representation, computer graphics, triangulation
series	CADline
last changed	2003/06/02 13:58

_id	c584
authors	Gerzso, Miguel J.
year	1979
title	Spacemaker : A Computer Language for Modelling Architectural Physical Form
source	Application of Computers in Architecture, Building Design and Urban Planning, International Conference Proceedings. 1979. pp. 573-582 : ill. includes bibliography
summary	The paper describes a modeling technique of architectural form. The technique is divided into two parts. A diagrammatic production system and a computer language. The production notation serves as a representation of underlying organization of building groups. The computer language -- SPACEMAKER -- facilitates the coding of such rules for computer programming. The particular version of the diagrammatic production system as presented first began by attempting to apply two picture grammars to architectural problems. The first effort was based on PDL developed by Allen Shaw and was called SNARQ I and the second one grew out of work done by Yun-chung Cho and was called SNARQ II. A few years later, these notations evolved into the notation presented after adapting ideas from A. Lindenmeyer. Numerous models of architectural systems were then constructed
keywords	architecture, languages, modeling
series	CADline
last changed	2003/06/02 13:58

_id	8e4d
authors	Hartley, P.J. and Judd, C.J.
year	1979
title	Curve and Surface Representations for Bezier B-spline Systems
source	1979? pp. 226- 236 : ill. includes bibliography
summary	The Bezier approach to the computer-aided design of surfaces, using interactive design of curves to construct surface sections, can be implemented using spline curves just as well as the original polynomial curves, and with some advantages. In the paper, some problems are considered that arise when a Bezier system is formulated and describe possible solutions for a spline-based system
keywords	curves, representation, CAD, curved surfaces, B-splines, Bezier,
series	CADline
last changed	2003/06/02 13:58

_id	c3b5
authors	Hinds, John K. and Kuan, L.P.
year	1979
title	Sculptured Surface Technology as a Unified Approach to Geometric Definition
source	CASA - The Computer and Automated System Association of SME. 23 p. : ill Dearborn: SME, 1979. MS79-146. includes bibliography.
summary	The purpose of this paper is to describe a comprehensive approach to representing and machining complex surface shapes in an APT programming system. The APT (Automatically Programmed Tools) user language was extended to permit the definition of a hierarchy of curves and surfaces. Much of the logic has been implemented using matrix canonical forms which are closed under the full family of projective transformations, permitting family of parts storage and retrieval and part compensation. The area of numerical control machining was addressed, but the solutions for tool positioning were only partially successful due to the complexity of the algorithmic problem. This paper first outlines some of the mathematical methods adopted and then illustrates how these have been implemented with an APT part programming example
keywords	curved surfaces, representation, geometric modeling, mechanical engineering, CAM
series	CADline
last changed	2003/06/02 13:58

_id	a4cc
authors	Hunter, Gregory M. and Steiglitz, Kenneth
year	1979
title	Operations on Images Using Quad Trees
source	IEEE Transactions on Pattern Analysis and Machine Intelligence. April, 1979. vol. PAMI-1: pp. 145-153 : ill. includes bibliography
summary	A quad tree for representing a picture is a tree in which successively deeper levels represent successively finer subdivisions of picture area. An algorithm is given for superposing N quad trees in time proportional to the total number of nodes in the trees. Warnock-type algorithms are then presented for building the quad tree for the picture of the boundary of a polygon, and for coloring the interior of such a polygon. These algorithms take O(v + p + q) time, where v is the number of polygon vertices, p is the polygon perimeter, and q is a resolution parameter. When the resolution q is fixed, these algorithms are asymptotically optimal
keywords	GIS, mapping, CAD, layout, pattern recognition, polyhedra, quadtree, planning, image processing, computer graphics
series	CADline
last changed	2003/06/02 13:58

_id	2ccd
authors	Kalisperis, Loukas N.
year	1994
title	3D Visualization in Design Education
doi	https://doi.org/10.52842/conf.acadia.1994.177
source	Reconnecting [ACADIA Conference Proceedings / ISBN 1-880250-03-9] Washington University (Saint Louis / USA) 1994, pp. 177-184
summary	It has been said that "The beginning of architecture is empty space." (Mitchell 1990) This statement typifies a design education philosophy in which the concepts of space and form are separated and defined respectively as the negative and positive of the physical world, a world where solid objects exist and void-the mere absence of substance-is a surrounding atmospheric emptiness. Since the beginning of the nineteenth century, however, there has been an alternative concept of space as a continuum: that there is a continuously modified surface between the pressures of form and space in which the shape of the space in our lungs is directly connected to the shape of the space within which we exist. (Porter 1979). The nature of the task of representing architecture alters to reflect the state of architectural understanding at each period of time. The construction of architectural space and form represents a fundamental achievement of humans in their environment and has always involved effort and materials requiring careful planning, preparation, and forethought. In architecture there is a necessary conversion to that which is habitable, experiential, and functional from an abstraction in an entirely different medium. It is often an imperfect procedure that centers on the translation rather than the actual design. Design of the built environment is an art of distinctions within the continuum of space, for example: between solid and void, interior and exterior, light and dark, or warm and cold. It is concerned with the physical organization and articulation of space. The amount and shape of the void contained and generated by the building create the fabric and substance of the built environment. Architecture as a design discipline, therefore, can be considered as a creative expression of the coexistence of form and space on a human scale. As Frank Ching writes in Architecture: Form, Space, and Order, "These elements of form and space are the critical means of architecture. While the utilitarian concerns of function and use can be relatively short lived, and symbolic interpretations can vary from age to age, these primary elements of form and space comprise timeless and fundamental vocabulary of the architectural designer." (1979)
series	ACADIA
email
last changed	2022/06/07 07:52

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