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 08ba
authors Requicha, Aristides A.G.
year 1980
title Representations for Rigid Solids : Theory, Methods, and Systems
source Computing Surveys December, 1980. vol. 12: pp. 437-464 : ill. includes bibliography.
summary Computer-based systems for modeling the geometry of rigid solid objects are becoming increasingly important in mechanical and civil engineering, architecture, computer graphics, computer vision, and other fields that deal with spatial phenomena. At the heart of such systems are symbol structures (representations) designating 'abstract solids' (subsets of Euclidean space) that model physical solids. Representations are the sources of data for procedures which compute useful properties of objects. The variety and uses of systems embodying representations of solids are growing rapidly, but so are the difficulties in assessing current designs, specifying the characteristics that future systems should exhibit, and designing systems to meet such specifications. This paper resolves many of these difficulties by providing a coherent view, based on sound theoretical principles, of what is presently known about the representation of solids. The paper is divided into three parts. The first introduces a simple mathematical framework for characterizing certain important aspects of representations, for example, their semantic (geometric) integrity. The second part uses the framework to describe and compare all of the major known schemes for representing solids. The third part briefly surveys extant geometric modeling systems and then applies the concepts developed in the paper to the high-level design of a multiple- representation geometric modeling system which exhibits a level of reliability and versatility superior to that of systems currently used in industrial computer-aided design and manufacturing
keywords CAD, CAM, computational geometry, geometric modeling, representation,CSG, B-rep
series CADline
last changed 2003/06/02 11:58

_id 4580
authors Borgerson, B. R. and Johnson, Robert H.
year 1980
title Beyond CAD to Computer Aided Engineering
source (8) p. : ill. Manufacturing Data Systems Incorporated, 1980? includes bibliography
summary Current CAD systems significantly aid the drafting function and many provide some aid to selected design activities. For the development of mechanical systems, much more can be done. Future systems will aid the interactive engineering process of design, analysis, control, documentation, and manufacturing engineering. Computer based systems which address this broader spectrum of engineering activities are referred to as `Computer Aided Engineering,' or `CAE,' systems. CAE systems will use volumetric techniques to create and evaluate the individual components of a machine design in conjunction with data base management schemas to support the interrelationships of the components of machines. This paper focuses on computer assistance to the engineering of mechanical systems
keywords mechanical engineering, CAE, solid modeling, objects
series CADline
last changed 2003/06/02 11:58

_id a2d4
authors Timmer, H.G. and Stern, J.M.
year 1980
title Computation of Global Geometric Properties of Solid Objects
source Computer Aided Design November, 1980. vol. 12: pp. 301-304 : ill. includes bibliography.
summary A computational scheme for determining global geometric properties of solid object models is presented. The method operates directly on the boundary representation of the model. The scheme is tested on a number of models produced by an experimental modeling system. Primitive objects combined for the tests are all represented in terms of parametric bicubic patches
keywords objects, solid modeling, computation, B-rep, curved surfaces
series CADline
last changed 2003/06/02 11:58

_id 76ce
authors Grimson, W.
year 1985
title Computational Experiments with a Feature Based Stereo Algorithm
source IEEE Trans. Pattern Anal. Machine Intell., Vol. PAMI-7, No. 1
summary Computational models of the human stereo system' can provide insight into general information processing constraints that apply to any stereo system, either artificial or biological. In 1977, Marr and Poggio proposed one such computational model, that was characterized as matching certain feature points in difference-of-Gaussian filtered images, and using the information obtained by matching coarser resolution representations to restrict the search'space for matching finer resolution representations. An implementation of the algorithm and'its testing on a range of images was reported in 1980. Since then a number of psychophysical experiments have suggested possible refinements to the model and modifications to the algorithm. As well, recent computational experiments applying the algorithm to a variety of natural images, especially aerial photographs, have led to a number of modifications. In this article, we present a version of the Marr-Poggio-Gfimson algorithm that embodies these modifications and illustrate its performance on a series of natural images.
series journal paper
last changed 2003/04/23 13:14

_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 m.barros@ipt.pt
last changed 2012/02/11 18:21

_id 8593
authors Braid, I.C.
year 1980
title Superficial Blends in Geometric Modelling
source 12 p. : ill. February, 1980. Document No. 105. includes bibliography
summary In engineering practice, many blended surfaces are both indicated and manufactured by rounding off a sharp edge. The authors term them `superficial' blends in contrast to `designed' blends for which existing surface techniques are appropriate. The provision of superficial blends in a geometric modeling system is explained, and a method is given for drawing objects containing blended edges
keywords geometric modeling, CAD, representation, solids
series CADline
last changed 2003/06/02 11:58

_id e952
authors Carrara, Gianfranco and Paoluzzi, Alberto
year 1980
title A Systems Approach to Building Program Planning
source computer Aided Building Design Laboratory Research Report. 80 p. : ill. Rome, Italy: December, 1980. CABD LAB RR. 80-02. includes bibliography
summary In this paper problems of design performance and of building program planning are considered from the view point of the general system theory. After having formalized the concept of requirement, performance and performance specification, it is shown that a set of building objects (spaces and constructive elements) foreseeable within a program is a semilattice, and that therefore the ordering of constructive elements and spaces corresponds to an ordering of relations among feasible 'behaviors.' A set of feasible behaviors is then presented as an abstract system, eventually discussing some assumptions on which to base an input-state-output representation of it
keywords theory, methods, problem solving, architecture, design, knowledge
series CADline
last changed 2003/06/02 11:58

_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 11:58

_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 13:14

_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 mkalviai@kacd.pspt.fi
more http://www.generativeart.com/
last changed 2003/08/07 15:25

_id 244d
authors Monedero, J., Casaus, A. and Coll, J.
year 1992
title From Barcelona. Chronicle and Provisional Evaluation of a New Course on Architectural Solid Modelling by Computerized Means
source CAAD Instruction: The New Teaching of an Architect? [eCAADe Conference Proceedings] Barcelona (Spain) 12-14 November 1992, pp. 351-362
summary The first step made at the ETSAB in the computer field goes back to 1965, when professors Margarit and Buxade acquired an IBM computer, an electromechanical machine which used perforated cards and which was used to produce an innovative method of structural calculation. This method was incorporated in the academic courses and, at that time, this repeated question "should students learn programming?" was readily answered: the exercises required some knowledge of Fortran and every student needed this knowledge to do the exercises. This method, well known in Europe at that time, also provided a service for professional practice and marked the beginning of what is now the CC (Centro de Calculo) of our school. In 1980 the School bought a PDP1134, a computer which had 256 Kb of RAM, two disks of 5 Mb and one of lO Mb, and a multiplexor of 8 lines. Some time later the general politics of the UPC changed their course and this was related to the purchase of a VAX which is still the base of the CC and carries most of the administrative burden of the school. 1985 has probably been the first year in which we can talk of a general policy of the school directed towards computers. A report has been made that year, which includes an inquest adressed to the six Departments of the School (Graphic Expression, Projects, Structures, Construction, Composition and Urbanism) and that contains interesting data. According to the report, there were four departments which used computers in their current courses, while the two others (Projects and Composition) did not use them at all. The main user was the Department of Structures while the incidence of the remaining three was rather sporadic. The kind of problems detected in this report are very typical: lack of resources for hardware and software and for maintenance of the few computers that the school had at that moment; a demand (posed by the students) greatly exceeding the supply (computers and teachers). The main problem appeared to be the lack of computer graphic devices and proper software.

series eCAADe
email monedero@ega1.upc.es
last changed 1998/08/18 14:29

_id sigradi2014_172
id sigradi2014_172
authors Santos, Fábio Lopes Souza; Rafael Goffinet de Almeida
year 2014
title Dan Graham e a cidade contemporânea: dispositivos espaciais, comportamentos e relações de poder
source SiGraDi 2014 [Proceedings of the 18th Conference of the Iberoamerican Society of Digital Graphics - ISBN: 978-9974-99-655-7] Uruguay - Montevideo 12 - 14 November 2014, pp. 505-508
summary Dan Graham became an important reference in contemporary art developing since the 1960´s a series of works that maintain a profound relation with urban cultural phenomena. This article proposes the analysis of his works produced over the 1970´s and 1980´s which presents the use of technical supports like video, exhibition and surveillance systems and which guided his earlier aesthetic research – related to the “institutional critique” – to the investigations about the power relations between objects, public and the space where they are placed.
keywords Dan Graham; Contemporary Art; Contemporary Architecture; Contemporary City; Contemporary Spatiality
series SIGRADI
email sotosantos@uol.com.br
last changed 2016/03/10 08:59

_id 0830
authors Ball, A. A.
year 1980
title How to Make the Bicubic Patch Work Using Reparametrisation
source 1980 ? 11 p. includes bibliography
summary This paper comprises a series of examples in numerical surface definition, loosely strung together, to show the practical limitations of the bicubic patch and how they can be overcome by reparametrisation. The concept of reparametrisation is more general than that used in computer- aided geometric design insofar as the reparametrisation is modeled in addition to the basic parametric equation
keywords CAD, computational geometry, curved surfaces, parametrization
series CADline
last changed 2003/06/02 11:58

_id 2fdd
authors Barsky, Brian A. and Thomas, Spencer W.
year 1980
title Transpline Curve Representation System
source April, 1980. 19 p. : ill. includes bibliography
summary An interactive curve representation system has been developed based on the concept of transforming among several parametric spline curve formulations. The available formulations are the interpolatory spline, uniform B-spline, spline under tension, and NU-spline. The system implementation is described in the context of a sample design session
keywords computational geometry, curves, representation, splines
series CADline
last changed 2003/06/02 11:58

_id a24e
authors Barstow, David R.
year 1980
title Knowledge Based Program Construction
source The Computer Science Library, 34 p.
summary Some aspects of the implementation of the reachability algorithm are presented.
keywords Knowledge Base, Programming, Graphs, LISP
series CADline
last changed 1999/02/15 13:58

_id 8629
authors Barzilay, Amos
year 1980
title Human Problem Solving on Master Mind
source Carnegie Mellon University
summary The purpose of this work is to analyze the task of playing Master Mind and to examine subjects behaviors on solving that task. The methods and the ideas that are used in the work are the same found in the references for other tasks. The author wants to show that those ideas and methods can be used for that specific task as well. In other words, subjects behave in such a domain as an information processing system. [includes bibliography]
keywords Psychology, Problem Solving
series CADline
last changed 1999/02/15 14:10

_id e825
authors Baybars, Ilker and Eastman, Charles M.
year 1980
title Enumerating Architectural Arrangements by Generating Their Underlying Graphs
source Environment and Planning B. 1980. vol. 7: pp. 289- 310 : ill. includes bibliography. -- See also 'Enumerating Architectural Arrangements: Comment on a Recent Paper by Baybars and Eastman' by C.F. Earl
summary One mathematical correspondence to the partitioning of the plane is a Weighted Plane Graph (WPG). This paper first focuses on the systematic generation of WPGs, in a fashion similar to crystal growth. During this process, the WPGs are represented by adjacency matrices. The authors, thus, present a method for embedding the WPG in the plane, given its adjacency matrix. These graphs can, then, be mapped into floor plans. The common practice here is the use of the `geometric dual' of a WPG. The authors propose, instead, the use of the `Pseudogeometric dual' of a WPG directly to translate (part of) a design brief into alternative spatial layouts. Also discussed is the ability to create courtyards and/or circulation spaces given a specific WPG, without increasing the size of the problem
keywords enumeration, architecture, floor plans, graphs, design process, automation, algorithms, space allocation, CAD
series CADline
email chuck.eastman@arch.gatech.edu
last changed 2003/05/17 08:15

_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 “gingerbread houses”, 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 deborahbenros@gmail.com
last changed 2012/02/11 18:21

_id 8a27
authors Bentley, Jon L. and Carruthers, Wendy
year 1980
title Algorithms for Testing the Inclusion of Points in Polygons
source Allertorn Conference on Communication, Control and Computing (18th : 1980). (10) p. includes bibliography
summary Determining whether a given point lies inside or outside a simple polygon is an important problem in many applications, including computer vision systems and computer-assisted political redistricting systems. In this paper the authors give algorithms for inclusion problems that are efficient for polygons that are 'close to convex' in a certain precise sense. An empirical study of polygons that arise in several applications shows that typical polygons are indeed 'close to convex,' and a program implementing the algorithm shows that is extremely efficient on point sets of practical sizes
keywords point inclusion, polygons, algorithms, computational geometry
series CADline
last changed 2003/06/02 11:58

_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 14:07

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