L-reps : 2次元ディスプレイ上で3次元ピンポイントを可能にする2次元指向幾何変換モデル [in Japanese] L-Reps : A 2D-Oriented Geometric Transformation Model which allows 3D Pinpoint on 2D Display [in Japanese]
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In interactive geometric modeling, it is a key operation for a user to specify precisely an arbitrary point of interest in a computer-generated 3D finite work space. We point out that traditional ways of projection transformation have several difficulties in performing the above operation, which is called 3<I>D</I> <I>pinpoint</I> in this paper. In order to alleviate the 3D pinpoint difficulties, we propose <I>L-reps</I> (Lines representations) as a new geometric transformation model for standard 2D displays. L-reps is a 2D drafting-oriented geometric model, and a generalization of conventional <I>lines</I>: a 2D engineering drawing which has been commonly used for the design of ship hulls or automobile bodies. We provide here the data definition and manipulations of L-reps. Also, we present a methodology for utilizing L-reps in a solid modeling environment. Two-way conversion algorithms between B-reps and L-reps are developed as principal components of the hybrid modeling scheme, where precise and aesthetic design tasks can be performed simultaneously. A pilot geometric modeling system is implemented on the basis of the hybrid scheme. The feasibility of our approach is demonstrated with a camera design example on the system.
- Journal of Graphic Science of Japan
Journal of Graphic Science of Japan (67), 3-15, 1995-03-01
JAPAN SOCIETY FOR GRAPHIC SCIENCE