authors 
Medjdoub, Benachir 
year 
1999 
title 
Interactive 2D ConstraintBased Geometric Construction System 
source 
Proceedings of the Eighth International Conference on Computer Aided Architectural Design Futures [ISBN 0792385365] Atlanta, 78 June 1999, pp. 197212 
summary 
This paper presents a 2D ConstraintBased Geometric Construction System where positioning and manipulating geometry is very precise. An unusually simple interface makes this system particularly interactive and easy to use. In our approach, the geometry types supported are: points, lines, circles, ellipses, circular arcs and bspline curves. All the fundamental topologic constraints, i.e. tangent, parallel, perpendicular, coincident and concentric, are provided. Metric constraints, i.e. dividing the shapes into equal parts or fixing the geometric parameters, are also provided. These constraints are automatically applied by the application in response to the implied intentions of the end user. Dynamic modifications of partially dimensioned models are supported, whereby the design is modified while enforcing the constraints. A graphconstructive approach is used to solve the model. As we are dealing with partial modifications, this resolution technique is quite sufficient, and makes our system stable and flexible. Our approach focuses highly on interactivity. Positioning a shape constrained to another is made directly through the graphic interface. Constraint relaxation is also done by direct manipulations. Modifications are made by dragging the geometry, or by typing into a numerical panel displaying the free shape parameters. Again, existing constraints are maintained as those numbers are applied. Well constrained and underconstrained problems are discussed. This approach was developed in Java, JDK 3.0.1 of SGI's Java software. 
keywords 
Sketching, Geometric Constraints, Interactivity, Geometric construction, Dynamic Modifications 
series 
CAAD Futures 
email 
Benachir.Medjdoub@nottingham.ac.uk 
full text 
file.pdf (1,595,416 bytes) 
references 
Contenttype: text/plain

Aish, R. (1992)
ComputerAided Design Software to Augment the Creation of Form
, computer in Architecture, 97104, Longman, London




Alasdair, S., (et. al.) (1993)
Constraint Definition System: a ComputerAlgebra Based Approach to Solving GeometricConstraint Problem
, Computer Aided Design, 25 (12) 741750




Aldefeld, B. (1988)
Variation of Geometries Based on a GeometricReasoning Method
, Computer Aided Design, 20 (3) 117126




Andre, G.P. (et. al.) (1992)
Computer Aids For Design Development
, Computer in Architecture, 1524, Longman, London




Borning, A. and Maher, M. (et. al.) (1989)
Constraints Hierarchies and Logic Programming
, Proc. Of the 6th Intemational Logic Programming Conference, 149164




Borning, A.H. (1981)
The Programming Language Aspects of ThingLab, a Constraint Oriented Simulation Laboratory
, ACM TOPLAS, 3 (4) 353387




Bouma, W., (et. al.) (1995)
A Geometric Constraint Solver
, Computer Aided Design, 27 487501




Bruderlin, B. (1986)
Constructing Three Dimensional Geometric Objects Defined by Constraints
, Workshop on Interactive 3D Graphics A CM, I 11 129




Buchberger, B. (1988)
Algebraic Methods for Geometric Reasoning
, Annual Reviews in Computer Science, 3 85120




Dohmen, M. (1995)
A Survey of Constraint Satisfaction Techniques for Geometric Modeling
, Computer & Graphics 19 (6) 831845




Fudos, I. and Hoffmann, C.M. (1993)
Correctness Proof of a Geometric Constraint Solver
, Technical Report CSDTR93076, Department of Computer Sciences, Purdue University




Fudos, I. (1993)
Editable Representations for 2D Geometric Design
, Master of Science Thesis, Purdue University




Gao, X.S. and Chou, S.C. (1998)
Solving Geometric Constraint System, II. A Symbolic Approach and Decision of Reconstructability,
, Computer Aided Design, 30 (2) 115122




Gao, X.S. and Chou, S.C. (1998)
Solving Geometric Constraint Problems. I. A global propagation approach
, Computer Aided Design, 30 (1) 4754




Heydon, A. and Nelson, G. (1994)
The Juno2 Constraintbased Drawing Editor
, SRC Research Report 131a




Kondo, K. (1990)
PIGMOD: Parametric and Interactive Geometric Modeller for Mechanical Design
, Computer Aided Design, 22 (10) 633644




Kramer, G. (1992)
Solving Geometric Constraint Systems
, (MIT Press)




Light, R. and Gossard, D. (1982)
Modification of Geometric Models Through Variational Geometry
, Computer Aided Design, 14 (4) 209214




Owen, J.C. (1991)
Algebraic Solution for Geometry from Dimensional Constraints
, ACM Symp. Found. of Solid Modeling, Austin TX, 397407




Requicha, A. (1977)
Dimensioning and tolerancing
, Technical report, Production Automation Project, University of Rochester, PADL TM19.




last changed 
2006/11/07 06:22 
