Cumincad : CUMINCAD Papers : Search Results

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

PDF papers
References

Hits 1 to 20 of 80

Reformat results as: short short into frame detailed detailed into frame

_id	ascaad2007_019
id	ascaad2007_019
authors	Morsy, S.M.
year	2007
title	A Social Approach to Intelligent Buildings
source	Em‘body’ing Virtual Architecture: The Third International Conference of the Arab Society for Computer Aided Architectural Design (ASCAAD 2007), 28-30 November 2007, Alexandria, Egypt, pp. 229-242
summary	Intelligent buildings were a hot topic since the 1980's. The vision was to share building telecommunication backbones with energy management systems, fire alarms, security systems and even office automation. The benefits were touted to include cost savings for cabling and long term maintenance, plus a future potential for interoperability between systems. The potential within these concepts and the surrounding technology is vast, and lives of users are changing from the effects of Intelligent Buildings developments on their living and working environments. In other words, the main aim of building intelligent building is merely a technological trend. But using intelligent buildings has wider effects on users than intended. Neglecting the human aspects of the users may be considered as a shortcoming. This paper considers the causes of this new trend in architecture in a larger social context, from which the rationalism of building intelligent buildings must arise. This will be done through exploring the concepts and applications of intelligent buildings, showing how all of them affect human life in such many ways.
series	ASCAAD
email
last changed	2008/01/21 22:00

_id	ga9809
id	ga9809
authors	Kälviäinen, Mirja
year	1998
title	The ideological basis of generative expression in design
source	International Conference on Generative Art
summary	This paper will discuss issues concerning the design ideology supporting the use and development of generative design. This design ideology is based on the unique qualities of craft production and on the forms or ideas from nature or the natural characteristics of materials. The main ideology presented here is the ideology of the 1980´s art craft production in Finland. It is connected with the general Finnish design ideology and with the design ideology of other western countries. The ideology for these professions is based on the common background of design principles stated in 19th century England. The early principles developed through the Arts and Crafts tradition which had a great impact on design thinking in Europe and in the United States. The strong continuity of this design ideology from 19th century England to the present computerized age can be detected. The application of these design principles through different eras shows the difference in the interpretations and in the permission of natural decorative forms. The ideology of the 1980ïs art craft in Finland supports the ideas and fulfilment of generative design in many ways. The reasons often given as the basis for making generative design with computers are in very many respects the same as the ideology for art craft. In Finland there is a strong connection between art craft and design ideology. The characteristics of craft have often been seen as the basis for industrial design skills. The main themes in the ideology of the 1980´s art craft in Finland can be compared to the ideas of generative design. The main issues in which the generative approach reflects a distinctive ideological thinking are: Way of Life: The work is the communication of the maker´s inner ideas. The concrete relationship with the environment, personality, uniqueness, communication, visionary qualities, development and growth of the maker are important. The experiments serve as a media for learning. Taste and Aesthetic Education: The real love affair is created by the non living object with the help of memories and thought. At their best objects create the basis in their stability and communication for durable human relationships. People have warm relationships especially with handmade products in which they can detect unique qualities and the feeling that the product has been made solely for them. Counter-culture: The aim of the work is to produce alternatives for technoburocracy and mechanical production and to bring subjective and unique experiences into the customerïs monotonious life. This ideology rejects the usual standardized mass production of our times. Mythical character: There is a metamorphosis in the birth of the product. In many ways the design process is about birth and growth. The creative process is a development story of the maker. The complexity of communication is the expression of the moments that have been lived. If you can sense the process of making in the product it makes it more real and nearer to life. Each piece of wood has its own beauty. Before you can work with it you must find the deep soul of its quality. The distinctive traits of the material, technique and the object are an essential part of the metamorphosis which brings the product into life. The form is not only for formïs sake but for other purposes, too. You cannot find loose forms in nature. Products have their beginnings in the material and are a part of the nature. This art craft ideology that supports the ideas of generative design can be applied either to the hand made crafts production or to the production exploiting new technology. The unique characteristics of craft and the expression of the material based development are a way to broaden the expression and forms of industrial products. However, for a crafts person it is not meaningful to fill the world with objects. In generative, computer based production this is possible. But maybe the production of unique pieces is still slower and makes the industrial production in that sense more ecological. People will be more attached to personal and unique objects, and thus the life cycle of the objects produced will be longer.
series	other
email
more	http://www.generativeart.com/
last changed	2003/08/07 17:25

_id	cdc2008_243
id	cdc2008_243
authors	Loukissas, Yanni
year	2008
title	Keepers of the Geometry: Architects in a Culture of Simulation
source	First International Conference on Critical Digital: What Matters(s)? - 18-19 April 2008, Harvard University Graduate School of Design, Cambridge (USA), pp. 243-244
summary	“Why do we have to change? We’ve been building buildings for years without CATIA?” Roger Norfleet, a practicing architect in his thirties poses this question to Tim Quix, a generation older and an expert in CATIA, a computer-aided design tool developed by Dassault Systemes in the early 1980’s for use by aerospace engineers. It is 2005 and CATIA has just come into use at Paul Morris Associates, the thirty-person architecture firm where Norfleet works; he is struggling with what it will mean for him, for his firm, for his profession. Computer-aided design is about creativity, but also about jurisdiction, about who controls the design process. In Architecture: The Story of Practice, Architectural theorist Dana Cuff writes that each generation of architects is educated to understand what constitutes a creative act and who in the system of their profession is empowered to use it and at what time. Creativity is socially constructed and Norfleet is coming of age as an architect in a time of technological but also social transition. He must come to terms with the increasingly complex computeraided design tools that have changed both creativity and the rules by which it can operate. In today’s practices, architects use computer-aided design software to produce threedimensional geometric models. Sometimes they use off-the-shelf commercial software like CATIA, sometimes they customize this software through plug-ins and macros, sometimes they work with software that they have themselves programmed. And yet, conforming to Larson’s ideas that they claim the higher ground by identifying with art and not with science, contemporary architects do not often use the term “simulation.” Rather, they have held onto traditional terms such as “modeling” to describe the buzz of new activity with digital technology. But whether or not they use the term, simulation is creating new architectural identities and transforming relationships among a range of design collaborators: masters and apprentices, students and teachers, technical experts and virtuoso programmers. These days, constructing an identity as an architect requires that one define oneself in relation to simulation. Case studies, primarily from two architectural firms, illustrate the transformation of traditional relationships, in particular that of master and apprentice, and the emergence of new roles, including a new professional identity, “keeper of the geometry,” defined by the fusion of person and machine. Like any profession, architecture may be seen as a system in flux. However, with their new roles and relationships, architects are learning that the fight for professional jurisdiction is increasingly for jurisdiction over simulation. Computer-aided design is changing professional patterns of production in architecture, the very way in which professionals compete with each other by making new claims to knowledge. Even today, employees at Paul Morris squabble about the role that simulation software should play in the office. Among other things, they fight about the role it should play in promotion and firm hierarchy. They bicker about the selection of new simulation software, knowing that choosing software implies greater power for those who are expert in it. Architects and their collaborators are in a continual struggle to define the creative roles that can bring them professional acceptance and greater control over design. New technologies for computer-aided design do not change this reality, they become players in it.
email
last changed	2009/01/07 08:05

_id	acadia21_76
id	acadia21_76
authors	Smith, Rebecca
year	2021
title	Passive Listening and Evidence Collection
source	ACADIA 2021: Realignments: Toward Critical Computation [Proceedings of the 41st Annual Conference of the Association of Computer Aided Design in Architecture (ACADIA) ISBN 979-8-986-08056-7]. Online and Global. 3-6 November 2021. edited by B. Bogosian, K. Dörfler, B. Farahi, J. Garcia del Castillo y López, J. Grant, V. Noel, S. Parascho, and J. Scott. 76-81.
doi	https://doi.org/10.52842/conf.acadia.2021.076
summary	In this paper, I present the commercial, urban-scale gunshot detection system ShotSpotter in contrast with a range of ecological sensing examples which monitor animal vocalizations. Gunshot detection sensors are used to alert law enforcement that a gunshot has occurred and to collect evidence. They are intertwined with processes of criminalization, in which the individual, rather than the collective, is targeted for punishment. Ecological sensors are used as a “passive” practice of information gathering which seeks to understand the health of a given ecosystem through monitoring population demographics, and to document the collective harms of anthropogenic change (Stowell and Sueur 2020). In both examples, the ability of sensing infrastructures to “join up and speed up” (Gabrys 2019, 1) is increasing with the use of machine learning to identify patterns and objects: a new form of expertise through which the differential agendas of these systems are implemented and made visible. I trace the differential agendas of these systems as they manifest through varied components: the spatial distribution of hardware in the existing urban environment and / or landscape; the software and other informational processes that organize and translate the data; the visualization of acoustical sensing data; the commercial factors surrounding the production of material components; and the apps, platforms, and other forms of media through which information is made available to different stakeholders. I take an interpretive and qualitative approach to the analysis of these systems as cultural artifacts (Winner 1980), to demonstrate how the political and social stakes of the technology are embedded throughout them.
series	ACADIA
type	paper
email
last changed	2023/10/22 12:06

_id	acadia07_164
id	acadia07_164
authors	Diniz, Nancy; Turner, Alasdair
year	2007
title	Towards a Living Architecture
source	Expanding Bodies: Art • Cities• Environment [Proceedings of the 27th Annual Conference of the Association for Computer Aided Design in Architecture / ISBN 978-0-9780978-6-8] Halifax (Nova Scotia) 1-7 October 2007, 164-173
doi	https://doi.org/10.52842/conf.acadia.2007.164
summary	Interaction is the latest currency in architecture, as responsive components are now reacting to the inhabitant of the space. These components are designed and installed by the architect with a view to the phenomenology of space, where the experience of the environment is previewed and pre-constructed before it is translated into the conception of the space. However, this traditional approach to new technology leaves no scope for the architecture to be alive in and of itself, and thus the installed piece quickly becomes just that—an installation: isolated and uncontained by its environment. In this paper, we argue that a way to approach a responsive architecture is to design for a piece that is truly living, and in order to propose a living architecture first we need to understand what the architecture of a living system is. This paper suggests a conceptual framework based on the theory of Autopoiesis in order to create a “self-producing” system through an experiment entitled, “The Life of a Wall” (Maturana and Varela 1980). The wall has a responsive membrane controlled by a genetic algorithm that reconfigures its behaviour and learns to adapt itself continually to the evolutionary properties of the environment, thus becoming a situated, living piece.
series	ACADIA
email
last changed	2022/06/07 07:55

_id	2006_252
id	2006_252
authors	Penttilä, Hannu
year	2006
title	Managing the Changes within the Architectural Practice - The Effects of Information and Communication Technology (ICT)
source	Communicating Space(s) [24th eCAADe Conference Proceedings / ISBN 0-9541183-5-9] Volos (Greece) 6-9 September 2006, pp. 252-260
doi	https://doi.org/10.52842/conf.ecaade.2006.252
summary	The architectural working environment has changed during the last 30 years more than ever before. Most of the changes have been related with information and communication technologies (ICT). Architectural working methods and tools have changed profoundly, when CAD has replaced more traditional methods and tools. Communicative working environment and document management within design & construction has also been changed to digital, meaning email and project webs. Completing a traditional architectural profile of the 20th centrury, a drawer-designer, contemporary communicating and managing skills plus mastering ICT are needed today to operate modern architectural practise properly. The objective of this study is to create a change-oriented understanding of the contemporary architectural profession concentrating on architectural information management. The first phase, a literature study, will be followed by interviews and case-studies, to examine three hypothetically different periods of time: a) 1980-85 the era before CAD, the last days of hand-drawing, b) 1993-98 the era of digital drawing, the expansion of architectural CAD, c) 2000-05 the rise of integrated and pervasive web-supported digital design. The study will propose new aspects to be included in the modern architectural profile, namingly project coordination, collaborative team-work, design information integration and profound digital content management.
keywords	architectural profession; design practice; architectural ICT; change management
series	eCAADe
email
last changed	2022/06/07 08:00

_id	e3c1
authors	Rasdorf, William J. and Fenves, Stephen J.
year	1980
title	Design Specification Representation and Analysis
source	Computing in Civil Engineering Conference Proceedings (2nd : 1980 : Baltimore, MD.). American Society of Civil Engineers, pp. 102- 111. CADLINE has abstract only
summary	The conventional structures of decision tables, information networks, and outlines define the current methodology for the representation and use of design specifications. This paper explores the relationships at the interfaces between these three representational tools. New analysis strategies are presented that provide flexibility at the lower boundary of the information network by converting decision tables to subnetworks within the information network and by compressing multiple subtables into larger tables representing higher- level nodes in the network. Both generation and compression of the information network provide flexibility in organizing a specification. The ability to both generate and compress nodes and subnodes establishes a mean of representing all the relations among the data items of a specification and gives one more direct control over the level of detail of the information network. As a direct consequence of the ability to generate new nodes, new classifiers can be progressively attached to the nodes of the subnetwork, as well as to the nodes in the information network. As a result, specification requirements are more logically identified by the outline and requirements and data items which were previously hidden within decision table conditions and actions are now directly accessible from the outline. Conversely, items inconsequential to the outline can be compressed into nodes and removed from the outline. A computer program is presented that implements these network transformations. The program accurately represents the interface between the network and the decision table
keywords	civil engineering, decision making, representation, analysis
series	CADline
last changed	2003/06/02 13:58

_id	cf2011_p170
id	cf2011_p170
authors	Barros, Mário; Duarte José, Chaparro Bruno
year	2011
title	Thonet Chairs Design Grammar: a Step Towards the Mass Customization of Furniture
source	Computer Aided Architectural Design Futures 2011 [Proceedings of the 14th International Conference on Computer Aided Architectural Design Futures / ISBN 9782874561429] Liege (Belgium) 4-8 July 2011, pp. 181-200.
summary	The paper presents the first phase of research currently under development that is focused on encoding Thonet design style into a generative design system using a shape grammar. The ultimate goal of the work is the design and production of customizable chairs using computer assisted tools, establishing a feasible practical model of the paradigm of mass customization (Davis, 1987). The current research step encompasses the following three steps: (1) codification of the rules describing Thonet design style into a shape grammar; (2) implementing the grammar into a computer tool as parametric design; and (3) rapid prototyping of customized chair designs within the style. Future phases will address the transformation of the Thonet’s grammar to create a new style and the production of real chair designs in this style using computer aided manufacturing. Beginning in the 1830’s, Austrian furniture designer Michael Thonet began experimenting with forming steam beech, in order to produce lighter furniture using fewer components, when compared with the standards of the time. Using the same construction principles and standardized elements, Thonet produced different chairs designs with a strong formal resemblance, creating his own design language. The kit assembly principle, the reduced number of elements, industrial efficiency, and the modular approach to furniture design as a system of interchangeable elements that may be used to assemble different objects enable him to become a pioneer of mass production (Noblet, 1993). The most paradigmatic example of the described vision of furniture design is the chair No. 14 produced in 1858, composed of six structural elements. Due to its simplicity, lightness, ability to be stored in flat and cubic packaging for individual of collective transportation, respectively, No. 14 became one of the most sold chairs worldwide, and it is still in production nowadays. Iconic examples of mass production are formally studied to provide insights to mass customization studies. The study of the shape grammar for the generation of Thonet chairs aimed to ensure rules that would make possible the reproduction of the selected corpus, as well as allow for the generation of new chairs within the developed grammar. Due to the wide variety of Thonet chairs, six chairs were randomly chosen to infer the grammar and then this was fine tuned by checking whether it could account for the generation of other designs not in the original corpus. Shape grammars (Stiny and Gips, 1972) have been used with sucesss both in the analysis as in the synthesis of designs at different scales, from product design to building and urban design. In particular, the use of shape grammars has been efficient in the characterization of objects’ styles and in the generation of new designs within the analyzed style, and it makes design rules amenable to computers implementation (Duarte, 2005). The literature includes one other example of a grammar for chair design by Knight (1980). In the second step of the current research phase, the outlined shape grammar was implemented into a computer program, to assist the designer in conceiving and producing customized chairs using a digital design process. This implementation was developed in Catia by converting the grammar into an equivalent parametric design model. In the third phase, physical models of existing and new chair designs were produced using rapid prototyping. The paper describes the grammar, its computer implementation as a parametric model, and the rapid prototyping of physical models. The generative potential of the proposed digital process is discussed in the context of enabling the mass customization of furniture. The role of the furniture designer in the new paradigm and ideas for further work also are discussed.
keywords	Thonet; furniture design; chair; digital design process; parametric design; shape grammar
series	CAAD Futures
email
last changed	2012/02/11 19:21

_id	cf2011_p127
id	cf2011_p127
authors	Benros, Deborah; Granadeiro Vasco, Duarte Jose, Knight Terry
year	2011
title	Integrated Design and Building System for the Provision of Customized Housing: the Case of Post-Earthquake Haiti
source	Computer Aided Architectural Design Futures 2011 [Proceedings of the 14th International Conference on Computer Aided Architectural Design Futures / ISBN 9782874561429] Liege (Belgium) 4-8 July 2011, pp. 247-264.
summary	The paper proposes integrated design and building systems for the provision of sustainable customized housing. It advances previous work by applying a methodology to generate these systems from vernacular precedents. The methodology is based on the use of shape grammars to derive and encode a contemporary system from the precedents. The combined set of rules can be applied to generate housing solutions tailored to specific user and site contexts. The provision of housing to shelter the population affected by the 2010 Haiti earthquake illustrates the application of the methodology. A computer implementation is currently under development in C# using the BIM platform provided by Revit. The world experiences a sharp increase in population and a strong urbanization process. These phenomena call for the development of effective means to solve the resulting housing deficit. The response of the informal sector to the problem, which relies mainly on handcrafted processes, has resulted in an increase of urban slums in many of the big cities, which lack sanitary and spatial conditions. The formal sector has produced monotonous environments based on the idea of mass production that one size fits all, which fails to meet individual and cultural needs. We propose an alternative approach in which mass customization is used to produce planed environments that possess qualities found in historical settlements. Mass customization, a new paradigm emerging due to the technological developments of the last decades, combines the economy of scale of mass production and the aesthetics and functional qualities of customization. Mass customization of housing is defined as the provision of houses that respond to the context in which they are built. The conceptual model for the mass customization of housing used departs from the idea of a housing type, which is the combined result of three systems (Habraken, 1988) -- spatial, building system, and stylistic -- and it includes a design system, a production system, and a computer system (Duarte, 2001). In previous work, this conceptual model was tested by developing a computer system for existing design and building systems (Benr__s and Duarte, 2009). The current work advances it by developing new and original design, building, and computer systems for a particular context. The urgent need to build fast in the aftermath of catastrophes quite often overrides any cultural concerns. As a result, the shelters provided in such circumstances are indistinct and impersonal. However, taking individual and cultural aspects into account might lead to a better identification of the population with their new environment, thereby minimizing the rupture caused in their lives. As the methodology to develop new housing systems is based on the idea of architectural precedents, choosing existing vernacular housing as a precedent permits the incorporation of cultural aspects and facilitates an identification of people with the new housing. In the Haiti case study, we chose as a precedent a housetype called ‚Äúgingerbread houses‚Äù, which includes a wide range of houses from wealthy to very humble ones. Although the proposed design system was inspired by these houses, it was decided to adopt a contemporary take. The methodology to devise the new type was based on two ideas: precedents and transformations in design. In architecture, the use of precedents provides designers with typical solutions for particular problems and it constitutes a departing point for a new design. In our case, the precedent is an existing housetype. It has been shown (Duarte, 2001) that a particular housetype can be encoded by a shape grammar (Stiny, 1980) forming a design system. Studies in shape grammars have shown that the evolution of one style into another can be described as the transformation of one shape grammar into another (Knight, 1994). The used methodology departs takes off from these ideas and it comprises the following steps (Duarte, 2008): (1) Selection of precedents, (2) Derivation of an archetype; (3) Listing of rules; (4) Derivation of designs; (5) Cataloguing of solutions; (6) Derivation of tailored solution.
keywords	Mass customization, Housing, Building system, Sustainable construction, Life cycle energy consumption, Shape grammar
series	CAAD Futures
email
last changed	2012/02/11 19:21

_id	241c
authors	Boehm, Wolfgang
year	1980
title	Inserting New Knots into B-spline Curves
source	IPC Business Press. July, 1980. vol. 12: pp. 199-201 : ill. includes bibliography
summary	For some applications, further subdivision of a segment of a B-spline curve or B-spline surface is desirable. This paper provides an algorithm for this. The structure is similar to de Boor's algorithm for the calculation of a point on a curve. An application of the subdivision is illustrated
keywords	algorithms, B-splines, curves, curved surfaces
series	CADline
last changed	1999/02/12 15:07

_id	a587
authors	Cohen, Elaine, Lyche, Tom and Riesenfeld, Richard F.
year	1980
title	Discrete B-Splines and Subdivision Techniques in Computer-Aided Geometric Design and Computer Graphics
source	computer Graphics and Image Processing. October, 1980. vol. 14: pp. 87- 111 : ill. includes bibliography
summary	The relevant theory of discrete B-splines with associated new algorithms is extended to provide a framework for understanding and implementing general subdivision schemes for nonuniform B-splines. The new derived polygon corresponding to an arbitrary refinement of the knot vector for an existing B-spline curve, including multiplicities, is shown to be formed by successive evaluations of the discrete B-spline defined by the original vertices, the original knot vector, and the refined knot vector. Existing subdivision algorithms can be seen as proper special cases. General subdivision has widespread applications in computer-aided geometric design, computer graphics, and numerical analysis. The new algorithms resulting from the new theory lead to a unification of the display model, the analysis model, and other needed models into a single geometric model from which other necessary models are easily derived. New sample algorithms for interference calculation, contouring, surface rendering, and other important calculations are presented
keywords	computational geometry, theory, algorithms, computer graphics, B-splines, curved surfaces
series	CADline
last changed	2003/06/02 13:58

_id	ddss2004_ra-33
id	ddss2004_ra-33
authors	Diappi, L., P. Bolchim, and M. Buscema
year	2004
title	Improved Understanding of Urban Sprawl Using Neural Networks
source	Van Leeuwen, J.P. and H.J.P. Timmermans (eds.) Recent Advances in Design & Decision Support Systems in Architecture and Urban Planning, Dordrecht: Kluwer Academic Publishers, ISBN: 14020-2408-8, p. 33-49
summary	It is widely accepted that the spatial pattern of settlements is a crucial factor affecting quality of life and environmental sustainability, but few recent studies have attempted to examine the phenomenon of sprawl by modelling the process rather than adopting a descriptive approach. The issue was partly addressed by models of land use and transportation which were mainly developed in the UK and US in the 1970s and 1980s, but the major advances were made in the area of modelling transportation, while very little was achieved in the area of spatial and temporal land use. Models of land use and transportation are well-established tools, based on explicit, exogenouslyformulated rules within a theoretical framework. The new approaches of artificial intelligence, and in particular, systems involving parallel processing, (Neural Networks, Cellular Automata and Multi-Agent Systems) defined by the expression “Neurocomputing”, allow problems to be approached in the reverse, bottom-up, direction by discovering rules, relationships and scenarios from a database. In this article we examine the hypothesis that territorial micro-transformations occur according to a local logic, i.e. according to use, accessibility, the presence of services and conditions of centrality, periphericity or isolation of each territorial “cell” relative to its surroundings. The prediction capabilities of different architectures of supervised Neural networks are implemented to the south Metropolitan area of Milan at two different temporal thresholds and discussed. Starting from data on land use in 1980 and 1994 and by subdividing the area into square cells on an orthogonal grid, the model produces a spatial and functional map of urbanisation in 2008. An implementation of the SOM (Self Organizing Map) processing to the Data Base allows the typologies of transformation to be identified, i.e. the classes of area which are transformed in the same way and which give rise to territorial morphologies; this is an interesting by-product of the approach.
keywords	Neural Networks, Self-Organizing Maps, Land-Use Dynamics, Supervised Networks
series	DDSS
last changed	2004/07/03 22:13

_id	6a59
authors	Franklin, Randolph
year	1980
title	A Linear Time Exact Hidden Surface Algorithm
source	SIGGRAPH '80 Conference Proceedings. July, 1980. vol. 14 ; no. 3: pp. 117-133 : ill. includes bibliography
summary	This Paper presents a new hidden surface algorithm. Its output is the set of the visible pieces of edges and faces, and is as accurate as the arithmetic precision of the computer. Thus calculating the hidden surfaces for a higher resolution device takes no more time. If the faces are independently and identically distributed, then the execution time is linear in the number of faces. In particular, the execution time does not increase with the depth complexity. This algorithm overlays a grid on the screen whose fineness depends on the number and size of the faces. Edges and faces are sorted into grid cells. Only objects in the same cell can intersect or hide each other. Also, if a face completely covers a cell then nothing behind it in the cell is relevant. Three programs have tested this algorithm. The first verified the variable grid concept on 50,000 intersecting edges. The second verified the linear time, fast speed, and irrelevance of depth complexity for hidden lines on 10,000 spheres. This also tested depth complexities up to 30, and showed that perspective scenes with the farther objects smaller are even faster to calculate. The third verified this for hidden surfaces on 3,000 squares
keywords	hidden surfaces, algorithms, hidden lines, variables, grids, computer graphics, programming
series	CADline
last changed	2003/06/02 13:58

_id	c46e
authors	Fuchs, H., Kedem, Z.M. and Naylor, B.F.
year	1980
title	On Visible Surface Generation by a Priori Tree Structures
source	SIGGRAPH '80 Conference Proceedings. July, 1980. vol. 14 ; no. 3: pp. 124-133 : ill. includes bibliography
summary	This paper describes a new algorithm for solving the hidden surface (or line) problem, to more rapidly generate realistic images of 3-D scenes composed of polygons, and presents the development of theoretical foundations in the area as well as additional related algorithms. As in many applications the environment to be displayed consists of polygons many of whose relative geometric relations are static. It is attempted to capitalize on this by preprocessing the environment's database so as to decrease the run-time computations required to generate a scene. This preprocessing is based on generating a 'binary space partitioning' tree whose inorder traversal of visibility priority at run-time will produce a linear order, dependent upon the viewing position, on (parts of) the polygons, which can then be used to easily solve the hidden surface problem. In the application where the entire environment is static with only the viewing-position changing, as is common in simulation, the results presented will be sufficient to solve completely the hidden surface problem
keywords	hidden lines, hidden surfaces, algorithms, computer graphics, polygons
series	CADline
last changed	2003/06/02 14:42

_id	4990
authors	Gips, J. and Stiny, G.
year	1980
title	Production System and Grammars: a Uniform Characterization
source	Environment and Planning B. 1980. vol. 7: pp. 399-408 : tables. includes bibliography
summary	The common structure underlying production system formalisms is developed. A variety of production system formalisms are summarized in terms of this structure. The structure is useful both for understanding existing systems and for developing new ones
keywords	systems, shape grammars, theory
series	CADline
last changed	2003/06/02 13:58

_id	b190
authors	Goldberg, Adele and Robson, David
year	1983
title	Smalltalk-80: The language and its implementation
source	New York, NY: Addison Wesley Co
summary	Smalltalk-80 is the classic standard Smalltalk language as described in Smalltalk-80: The Language and Its Implementation by Goldberg and Robson. This book is commonly called "the Blue Book". Squeak implements the dialect of Smalltalk described in this book, but has a different implementation. Overview of the Smalltalk Language Smalltalk is a general purpose, high level programming language. It was the first original "pure" object oriented language, but not the first to use the object oriented concept, which is credited to Simula 67. The explosive growth of Object Oriented Programming (OOP) technologies began in the early 1980's, with Smalltalk's introduction. Behind it was the idea that the individual human user should be the most important component of any computing system, and that programming should be a natural extension of thinking, and also a dynamic and evolutionary process consistent with the model of human learning activity. In Smalltalk, these ideas are embodied in a framework for human-computer communication. In a sense, Smalltalk is yet another language like C and Pascal, and programs can be written in Smalltalk that have the look and feel of such conventional languages. The difference lies * in the amount of code that can be reduced, * less cryptic syntax, * and code that is easier to handle for application maintenance and enhancement. But Smalltalk's most powerful feature is easy code reuse. Smalltalk makes reuse of programs, routines, and subroutines (methods) far easier. Though procedural languages allow reuse too, it is harder to do, and much easier to cheat. It is no surprise that Smalltalk is relatively easy to learn, mainly due to its simple syntax and semantics, as well as few concepts. Objects, classes, messages, and methods form the basis of programming in Smalltalk. The general methodology to use Smalltalk The notion of human-computer interface also results in Smalltalk promoting the development of safer systems. Errors in Smalltalk may be viewed as objects telling users that confusion exists as to how to perform a desired function.
series	other
last changed	2003/04/23 15:14

_id	f773
id	f773
authors	Johnson, Brian R.
year	1990
title	Inside Out
source	From Research to Practice [ACADIA Conference Proceedings] Big Sky (Montana - USA) 4-6 October 1990, pp. 219-231
doi	https://doi.org/10.52842/conf.acadia.1990.219
summary	An effort to generate discussion, this paper suggests that between 1980 and 1990 a significant and undesirable change has occurred in academic architectural CAD. We have moved from being developers of ideas and technology on the inside of the development loop to being consumers of products developed in the commercial market place, outside the loop. Certain negative consequences are discussed. Finally, some suggestions are made for turning ourselves "right side out" again.
series	ACADIA
type	normal paper
email
last changed	2022/06/07 07:52

_id	c3f4
authors	Joy, William
year	1980
title	An Introduction to Display Editing with VI
source	September, 1980. 30 p
summary	VI (Visual) is a display oriented interactive text editor. When using VI the screen of the terminal acts as a window into the file which is being editing. Changes which made to the file are reflected in what is seen. Using VI the user can insert new text any place in the file quite easily. Most of the commands to VI move the cursor around in the file. There are commands to move the cursor forward and backward in units of characters, words, sentences and paragraphs. A small set of operators, like d for delete and c for change, are combined with the motion commands to form operations such as delete word or change paragraph, in a simple and natural way. This regularity and the mnemonic assignment of commands to keys makes the editor command set easy to remember and to use. VI works on a large number of display terminals, and new terminals are easily driven after editing a terminal description file. While it is advantageous to have an intelligent terminal which can locally insert and delete lines and characters from the display, the editor will function quite well on dumb terminals over slow phone lines. The editor makes allowances for the low bandwidth in these situations and uses smaller window sizes and different display updating algorithms to make best use of the limited speed available. It is also possible to use the command set of VI on hardcopy terminals, storage tubes and 'glass ty's' using a one line editing window; thus VI's command set is available on all terminals. The full command set of the more traditional, line oriented editor ED is available within VI; it is quite simple to switch between the two modes of editing
keywords	UNIX, display, word processing, software
series	CADline
last changed	1999/02/12 15:08

_id	0439
authors	Kant, Elaine
year	1980
title	A Knowledge-Based Approach to Using Efficiency Estimation in Program Synthesis
source	1980? pp. 457-462. includes bibliography
summary	This paper describes a system for using efficiency knowledge in program synthesis. The system, called LIBRA, uses a combination of knowledge-based rules and algebraic cost estimates to compare potential program implementations. Efficiency knowledge is used to control the selection of algorithm and data structure implementations and the application of optimizing transformations. Prototypes of programming constructs and of cost estimation techniques are used to simplify the efficiency analysis process and to assist in the acquisition of efficiency knowledge associated with new coding knowledge. LIBRA has been used to guide the selection of implementations for several programs that classify, retrieve information, sort, and generate prime numbers
keywords	knowledge base, systems, programming, performance, synthesis, evaluation
series	CADline
last changed	1999/02/12 15:08

_id	c4b8
authors	Lane, Jeffrey M. and Riesenfeld, Richard F.
year	1980
title	A Theoretical Development for the Computer Generation and Display of Piecewise Polynomial Surfaces
source	IEEE Transactions on Pattern Analysis and Machine Intelligence. January, 1980 Vol. PAM 1-2: pp. 35-46 : ill.
summary	includes a short bibliography. Two algorithms for parametric piecewise polynomial evaluation and generation are described. The mathematical development of these algorithms is shown to generalize to new algorithms for obtaining curve and surface intersections and for the computer display of parametric curves and surfaces
keywords	display, algorithms, intersection, CAD, computer graphics, B-splines, curved surfaces
series	CADline
last changed	2003/06/02 13:58

For more results click below: