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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	678e
authors	Aish, Robert
year	1986
title	Three-dimensional Input and Visualization
source	Computer-Aided Architectural Design Futures [CAAD Futures Conference Proceedings / ISBN 0-408-05300-3] Delft (The Netherlands), 18-19 September 1985, pp. 68-84
summary	The aim of this chapter is to investigate techniques by which man-computer interaction could be improved, specifically in the context of architectural applications of CAD. In this application the object being designed is often an assembly of defined components. Even if the building is not actually fabricated from such components, it is usually conceptualized in these terms. In a conventional graphics- based CAD system these components are usually represented by graphical icons which are displayed on the graphics screen and arranged by the user. The system described here consists of three- dimensional modelling elements which the user physically assembles to form his design. Unlike conventional architectural models which are static (i.e. cannot be changed by the users) and passive (i.e. cannot be read by a CAD system), this model is both 'user generated' and 'machine readable'. The user can create, edit and view the model by simple, natural modelling activities and without the need to learn complex operating commands often associated with CAD systems. In particular, the user can view the model, altering his viewpoint and focus of attention in a completely natural way. Conventional computer graphics within an associated CAD system are used to represent the detailed geometry which the different three-dimensional icons may represent. In addition, computer graphics are also used to present the output of the performance attributes of the objects being modelled. In the architectural application described in this chapter an energy- balance evaluation is displayed for a building designed using the modelling device. While this system is not intended to offer a completely free-form input facility it can be considered to be a specialist man-machine interface of particular relevance to architects or engineers.
series	CAAD Futures
email
last changed	2003/11/21 15:15

_id	4ed0
authors	Bartels, R.H., Beatty, J.C. and Barsky, B.A.
year	1986
title	An Introduction to Splines for Use in Computer Graphics and Geometric Modeling
source	xiv, 476 p. : ill. (some col.) Los Altos, California: Morgan Kaufmann Pub. Inc., 1986. Forewords by Pierre Bezier and Robin A. Forrest. Includes bibliography: p. 455-465 and index
summary	Discusses the use of splines from the point of view of the computer scientist concentrating on parametric spline curves and parametric,tensor-product spline surfaces
keywords	splines, theory, computer graphics, computational geometry
series	CADline
last changed	2003/06/02 14:42

_id	09b3
authors	Bier, Eric A. and Sloan, Kenneth R. Jr.
year	1986
title	Two-Part Texture Mappings
source	IEEE Computer Graphics and Applications September, 1986. pp. 40-53 : col. ill. includes bibliography.
summary	Most published techniques for mapping two-dimensional texture patterns onto three-dimensional curved surfaces assume that either the texture pattern has been predistorted to compensate for the distortion of the mapping or the curved surfaces are represented parametrically. The authors address the problem of mapping undistorted planar textures onto arbitrarily represented surfaces. Their mapping technique is done in two parts. First the texture pattern is embedded in 3- space on an intermediate surface. Then the pattern is projected onto the target surface in a way that depends only on the geometry of the target object (not on its parametrization). Both steps have relatively low distortion, so the original texture need not be predistorted. The authors also discuss interactive techniques that make two-part mapping practical
keywords	texture mapping, curved surfaces, computer graphics, rendering
series	CADline
last changed	2003/06/02 10:24

_id	8e02
authors	Brown, A.G.P. and Coenen, F.P.
year	2000
title	Spatial reasoning: improving computational efficiency
source	Automation in Construction 9 (4) (2000) pp. 361-367
summary	When spatial data is analysed the result is often very computer intensive: even by the standards of contemporary technologies, the machine power needed is great and the processing times significant. This is particularly so in 3-D and 4-D scenarios. What we describe here is a technique, which tackles this and associated problems. The technique is founded in the idea of quad-tesseral addressing; a technique, which was originally applied to the analysis of atomic structures. It is based on ideas concerning Hierarchical clustering developed in the 1960s and 1970s to improve data access time [G.M. Morton, A computer oriented geodetic database and a new technique on file sequencing, IBM Canada, 1996.], and on atomic isohedral (same shape) tiling strategies developed in the 1970s and 1980s concerned with group theory [B. Grunbaum, G.C. Shephard, Tilings and Patterns, Freeman, New York, 1987.]. The technique was first suggested as a suitable representation for GIS in the early 1980s when the two strands were brought together and a tesseral arithmetic applied [F.C. Holdroyd, The Geometry of Tiling Hierarchies, Ars Combanitoria 16B (1983) 211–244.; S.B.M. Bell, B.M. Diaz, F.C. Holroyd, M.J.J. Jackson, Spatially referenced methods of processing raster and vector data, Image and Vision Computing 1 (4) (1983) 211–220.; Diaz, S.B.M. Bell, Spatial Data Processing Using Tesseral Methods, Natural Environment Research Council, Swindon, 1986.]. Here, we describe how that technique can equally be applied to the analysis of environmental interaction with built forms. The way in which the technique deals with the problems described is first to linearise the three-dimensional (3-D) space being investigated. Then, the reasoning applied to that space is applied within the same environment as the definition of the problem data. We show, with an illustrative example, how the technique can be applied. The problem then remains of how to visualise the results of the analysis so undertaken. We show how this has been accomplished so that the 3-D space and the results are represented in a way which facilitates rapid interpretation of the analysis, which has been carried out.
series	journal paper
more	http://www.elsevier.com/locate/autcon
last changed	2003/05/15 21:22

_id	4418
authors	Franklin, Randolph, Wu, Peter, Y. F. and Samaddar, Sumitro (et al)
year	1986
title	Prolog and Geometry Projects
source	IEEE Computer Graphics and Applications. November, 1986. vol. 6: pp. 46-55 : ill. includes bibliography
summary	Prolog is a useful tool for geometry and graphics implementations because its primitives, such as unification, match the requirements of many geometric algorithms. During the last two years, programs have been implemented to solve several problems in Prolog, including a subset of the Graphical Kernel System, convex-hull calculation, planar graph traversal, recognition of groupings of objects, Boolean combinations of polygons using multiple precision rational numbers, and cartographic map overlay. Certain paradigms or standard forms of geometric programming in Prolog are becoming evident. They include applying a function to every element of a set, executing a procedure so long as a certain geometric pattern exists, and using unification to propagate a transitive function. This article describes the experiences, including paradigms of programming that seem useful, and finally lists those considered as the advantages and disadvantages of Prolog
keywords	geometric modeling, computer graphics, PROLOG, programming
series	CADline
last changed	2003/06/02 13:58

_id	a241
authors	Freund, Dwight D.
year	1986
title	A Note : An Interactive Procedure for Constructing Line and Circle Tangencies
source	IEEE Computer Graphics and Applications. April, 1986. vol. 6: pp. 59-63 : ill. includes bibliography
summary	This note describes a procedure that enables a designer or draftsperson with limited mathematical training to discover interactively the construction of a wide variety of tangency and intersection problems. Requiring very little code to implement, it supplements the standard tangency constructions available on commercial turnkey computer-aided-design systems with a flexibility unavailable even through the inclusion of the numerous special-purpose algorithms available in the literature
keywords	drawings, circles, computational geometry, user interface
series	CADline
last changed	2003/06/02 10:24

_id	0354
authors	Goodman, Gary and Reddy, Raj D.
year	1978
title	Alternative Control Structures for Speech Understanding Systems
source	1978 ? [13] p. : ill. includes bibliography Control structures are an essential part of any speech recognition system. They are the devices by which passive knowledge about the task and language is transformed into active and effective processes. In the chapter, three areas of control structures are defined and discussed: knowledge source interaction, knowledge source activation, and knowledge source focusing. Discussion relates the concepts presented to systems developed during the five-year ARPA speech understanding project. speech recognition / systems / control / structures / AI. 64. Goodman, Tim and Keith Unsworth. 'Manipulating Shape and Producing Geometric Continuity in B-spline Curves.' IEEE Computer Graphics and Applications. February, 1986. vol. 6: pp. 50-56 : ill. includes bibliography.
summary	This article examines some of the desirable features of B- splines that make them particularly suitable for computer- aided design. First, a theoretical analysis is presented regarding the effects upon the shape of a design curve when the bias and tension parameters are allowed to vary in certain ways. Second, the concept of geometric continuity is discussed, and conditions are derived upon the control vertices to ensure that the design curve has second-order geometric continuity. Illustrations of B-spline curves are presented to support the theoretical conclusions
keywords	computational geometry, B-splines, curves, CAD
series	CADline
last changed	2003/06/02 13:58

_id	4e59
authors	Koparkar, P. A. and Mudur, S.P.
year	1986
title	Generation of Continuous Smooth Curves Resulting from Operations on Parametric Surface Patches
source	Computer Aided Design. May, 1986. pp. 193-206 : ill. includes bibliography
summary	In recent years a number of techniques based on the subdivision principle have been suggested for detecting the curves resulting from the intersection of two parametrically defined surface patches. Silhouette curves of surfaces can also be detected using analogous techniques. Usually the output is a set of pixels or line segments which form the complete curve, though not necessarily in an ordered manner. This paper presents data structures for maintaining the result of subdivision, and algorithms for tracing the curves in a continuous fashion. Using a few iterations of the Newton-Raphson technique the curve points may be refined to any required precision. For each point on the curve the nonlinear equations are chosen by looking at the local topological nature of the curve so as to guarantee convergence of the Newton-Raphson technique in one or two iterations
keywords	curved surfaces, parametrization, curves, intersection, relaxation, geometric modeling, computational geometry
series	CADline
last changed	2003/06/02 14:41

_id	8816
authors	Penn, Michael A. and Patterson, Richard R.
year	1986
title	Projective Geometry and its Application to Computer Graphics
source	xi, 403 p. Englewood Cliffs, New Jersey: Prentice Hall, 1986. includes bibliography: p. 394-395
summary	The goal of the book is to support the design of solutions to computer graphic problems through an understanding of the underlying elements of projective geometry. Some of the topics discussed are: How to view the structure of two and three dimensional graphic libraries, how to create two dimensional perspective and parallel images of a three dimensional object, how to draw the graph of a function of two real variables, and more
keywords	computer graphics, projective geometry
series	CADline
last changed	2003/06/02 13:58

_id	4577
authors	Piegl, L.
year	1986
title	Representation of Rational Bezier Curves and Surfaces by Recursive Algorithms
source	Computer Aided Design Butterworth & Co. (publishers) Ltd., September, 1986. vol. 18: pp. 361-366 : ill.
summary	includes a short bibliography. Recursive algorithms for the computation and subdivision of rational Bezier curves and surfaces are presented. The development uses the relationship between the R4 geometry and the rational scheme
keywords	curves, curved surfaces, recursion, Bezier, representation
series	CADline
last changed	2003/06/02 13:58

_id	6728
authors	Rossignac, Jaroslaw R. and Requicha, Aristides A. G.
year	1986
title	Depth- Buffering Display Techniques for Constructive Solid Geometry
source	IEEE Computer Graphics and Applications. September, 1986. vol. 6: pp. 29-39 : ill. some col. includes bibliography
summary	Solid modelers based on constructive solid geometry (CSG) typically generate shaded displays directly from CSG by using ray-casting techniques, which do not require information on the faces, edges, and vertices that bound a solid. This article describes an alternative - a simple new algorithm based on a depth-buffering or z-buffering approach. The z- buffer display algorithm operates directly on CSG, does not require explicit boundary data, and is easier to implement than ray casting. Ray-casting and z-buffering algorithms have comparable performances, but z-buffering is often faster for objects with complex surfaces, because it avoids expensive curve/surface intersection calculations. Because of their simplicity, depth-buffering algorithms for CSG are well- suited to hardware implementations, and may lead to machines simpler than those now being built for ray casting
keywords	geometric modeling, CSG, display, computer graphics
series	CADline
last changed	2003/06/02 13:58

_id	28d8
authors	Sarnak, Neil and Tarjan, Robert E.
year	1986
title	Planar Point Location Using Persistent Search Trees
source	Communications of the ACM July, 1986. vol. 29: pp. 669-679 : ill. includes bibliography.
summary	A classical problem in computational geometry is the planar point location problem. This problem calls for preprocessing a polygonal subdivision of the plane defined by n line segments so that, given a sequence of points, the polygon containing each point can be determined quickly on-line. Several ways of solving this problem in O(log n) query time and O(n) space are known, but they are all rather complicated. The authors propose a simple O(log n) query-time, O(n) space solution, using persistent search trees. A persistent search tree differs from an ordinary search tree in that after an insertion or deletion, the old version of the tree can stillÔ h)000*°° ÔŒ be accessed. A persistent form of binary search tree that supports insertions and deletions in the present and queries in the past is developed. The time per query or update is O(log m), where m is the total number of updates, and the space needed is O(1) per update. The planar point location algorithm is an immediate application of this data structure. The structure also provides an alternative to Chazelle's 'hive graph' structure, which has a variety of applications in geometric retrieval
keywords	search, data structures, algorithms, point inclusion, computational geometry
series	CADline
last changed	2003/06/02 13:58

_id	c92d
authors	Sederberg, Thomas W. and Goldman, Ronald N.
year	1986
title	Algebraic Geometry for Computer-Aided Geometric Design
source	IEEE Computer Graphics and Applications. June, 1986. vol. 6: pp. 52-59
summary	An object description associating a tolerance with each of its topological features (vertices, edges, and faces) is introduced. The use of tolerances leads to a definition of topological consistency that is readily applied to boundary representations. The implications of using tolerances to aid in making consistent topological determinations from imprecise geometric data are explored and applied to the calculations of a polyhedral solid modeler
keywords	Algorithms; Curves; Computational Geometry; Mathematics; Education; Intersection
series	CADline
last changed	2003/06/02 10:24

_id	6fdc
authors	Gross, Mark D.
year	2001
title	FormWriter. A Little Programming Language for Generating Three-Dimensional Form Algorithmically
source	Proceedings of the Ninth International Conference on Computer Aided Architectural Design Futures [ISBN 0-7923-7023-6] Eindhoven, 8-11 July 2001, pp. 577-588
summary	FormWriter is a simple and powerful programming language for generating three-dimensional geometry, intended for architectural designers with little programming experience to be able to generate three dimensional forms algorithmically without writing complex code. FormWriter’s main features include a unified coding and graphics environment providing immediate feedback and a “flying turtle” - a means of generating three dimensional data through differential geometry.
keywords	Programming Language, Geometry, Form Generation
series	CAAD Futures
email
last changed	2006/11/07 07:22

_id	acadia16_130
id	acadia16_130
authors	Koschitz, Duks; Ramagosa, Bernat; Rosenbaum, Eric
year	2016
title	Beetle Blocks: A New Visual Language for Designers and Makers
doi	https://doi.org/10.52842/conf.acadia.2016.130
source	ACADIA // 2016: POSTHUMAN FRONTIERS: Data, Designers, and Cognitive Machines [Proceedings of the 36th Annual Conference of the Association for Computer Aided Design in Architecture (ACADIA) ISBN 978-0-692-77095-5] Ann Arbor 27-29 October, 2016, pp. 130-139
summary	We are introducing a new teaching tool to show designers, architects, and artists procedural ways of constructing objects and space. Computational algorithms have been used in design for quite some time, but not all tools are very accessible to novice programmers, especially undergraduate students. ‘Beetle Blocks’ (beetleblocks.com) is a software environment that combines an easy-to-use graphical programming language with a generative model for 3D space, drawing on ‘turtle geometry,’ a geometry paradigm introduced by Abelson and Disessa, that uses a relative as opposed to an absolute coordinate system. With Beetle Blocks, designers are able to learn computational concepts and use them for their designs with more ease, as individual computational steps are made visually explicit. The beetle, the relative coordinate system, follows instructions as it moves about in 3D space. Anecdotal evidence from studio teaching in undergraduate programs shows that despite the early introduction of digital media and tools, architecture students still struggle with learning formal languages today. Beetle Blocks can significantly simplify the teaching of complex geometric ideas and we explain how this can be achieved via several examples. The blocks-based programming language can also be used to teach fundamental concepts of manufacturing and digital fabrication and we elucidate in this paper which possibilities are conducive for 2D and 3D designs. This project was previously implemented in other languages such as Flash, Processing and Scratch, but is now developed on top of Berkeley’s ‘Snap!’
keywords	generative design, design pedagogy, digital fabrication, tool-building, pedagogical tools
series	ACADIA
type	paper
email
last changed	2022/06/07 07:51

_id	4c79
authors	Aguilar, Lorenzo
year	1986
title	A Format for a Graphical Communications Protocol
source	IEEE Computer Graphics and Applications vol. 6.no. 3 (March, 1986): pp. 52-62
summary	This article describes the requirements for a graphical format on which a graphical on-line communications protocol can be based. It is argued that on-line graphical communications is similar to graphical session capture, and thus the author proposes an interactive graphical communications format using the GKSM session metafile. The discussion includes items that complement the GKSM metafile such as a format for on-line interactive exchange. One key application area of such a format is multimedia on-line conferencing. Therefore, a conferencing software architecture for processing the proposed format is presented. This format specification is made available to those planning multimedia conferencing systems
keywords	user interface, communication, computer graphics, multimedia, standards
series	CADline
last changed	1999/02/12 15:07

_id	2ec8
authors	Arditi, Aries and Gillman, Arthur E.
year	1986
title	Computing for the Blind User
source	BYTE Publication Inc. March, 1986. pp. 199-208. includes some reference notes
summary	In this article the authors present some of the human-factors issues specific to non visual personal computing. The authors' concern is with the accuracy, speed, and generality of the blind-user interface, to make computers more accessible and efficient for blind and visually impaired persons
keywords	user interface, disabilities
series	CADline
last changed	2003/06/02 13:58

_id	a35a
authors	Arponen, Matti
year	2002
title	From 2D Base Map To 3D City Model
source	UMDS '02 Proceedings, Prague (Czech Republic) 2-4 October 2002, I.17-I.28
summary	Since 1997 Helsinki City Survey Division has proceeded in experimenting and in developing the methods for converting and supplementing current digital 2D base maps in the scale 1:500 to a 3D city model. Actually since 1986 project areas have been produced in 3D for city planning and construction projects, but working with the whole map database started in 1997 because of customer demands and competitive 3D projects. 3D map database needs new data modelling and structures, map update processes need new working orders and the draftsmen need to learn a new profession; the 3D modeller. Laser-scanning and digital photogrammetry have been used in collecting 3D information on the map objects. During the years 1999-2000 laser-scanning experiments covering 45 km2 have been carried out utilizing the Swedish TopEye system. Simultaneous digital photography produces material for orto photo mosaics. These have been applied in mapping out dated map features and in vectorizing 3D buildings manually, semi automatically and automatically. In modelling we use TerraScan, TerraPhoto and TerraModeler sw, which are developed in Finland. The 3D city model project is at the same time partially a software development project. An accuracy and feasibility study was also completed and will be shortly presented. The three scales of 3D models are also presented in this paper. Some new 3D products and some usage of 3D city models in practice will be demonstrated in the actual presentation.
keywords	3D City modeling
series	other
email
more	www.udms.net
last changed	2003/11/21 15:16

_id	242d
authors	Atkin, Brian L. and Gill, E. Moira
year	1986
title	CAD and Management of Construction Projects
source	Journal of Construction Engineering and Management, Vol. 112, December, pp. 557-565
summary	The increasing interest in computer-aided design (CAD) has prompted research that is aimed at identifying the opportunities for construction managers and building contractors. It has been found that the use of CAD systems in the U.K. is mainly confined to the production of detailed drawings. Indeed, most of the systems used are 2-D drafting tools and incapable of supporting the integration of even modest amounts of nongraphical (construction) data. On the other hand, many 3-D modeling systems have the potential to integrate construction data, although they appear to be almostignored. The use of 3-D modeling systems is considered to be the most suitable vehicle for successfully integrating these data. However, this is likely to necessitate the introduction of separate databases, preferably of the relational type. The use of 3-D modeling systems in assessing the construction implications of outline designs also presents interesting possibilities and is discussed.
series	journal paper
last changed	2003/04/23 15:14

_id	0f76
authors	Balachandran, M. B. and Gero, John S.
year	1986
title	Knowledge-based Design Optimization
source	IAAI'86 Conference. 1986. pp. i:4:1-14
summary	CADLINE has abstract only. Optimization is a well understood process in design domains. A designer formulates the design problem as a single criterion or multicriteria optimization problem and then selects an appropriate optimization algorithm to search for the optimal values for the design variables. The formulation and algorithm selection procedures have been considered to be activities which relied on substantive human knowledge. This paper describes a computer system, OPTIMA, which formulates design optimization problems from a pseudo-English description into canonical algebraic expressions. It then recognizes the formulation and selects appropriate algorithm(s) for their solutions. Finally, it runs the selected algorithm(s) and sends the results to the original descriptions. Areas of expert knowledge involved in carrying out the above tasks are identified. Such knowledge is explicitly encoded in the systems. The basic philosophy and key features of the system are described and are illustrated by examples
keywords	algorithms, expert systems, knowledge base, design, optimization, structures, engineering
series	CADline
email
last changed	2003/06/02 13:58

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