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Modeling with Features
September-October 1997 (vol. 17 no. 5)
pp. 40-46
Sculptors and animators have requirements different from those of engineers. Existing freeform modeling methods do not address those requirements. We propose a new kind of parametric surface model based on the notion of features. In ordinary language, a feature is a logically distinct area of a surface or some characteristic of part of a surface. For the purpose of the modeler, we define a feature as a combination of a blending function and a shape generator. This leads to a natural extension of the idea of a parametric surface controlled by position vectors. Features can be introduced anywhere on the surface, added and combined to create complex shapes. We have built an experimental surface editor using these principles. Examples of shape creation and manipulation are presented.

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Geoff Wyvill, Dean McRobie, Michael Gigante, "Modeling with Features," IEEE Computer Graphics and Applications, vol. 17, no. 5, pp. 40-46, Sept.-Oct. 1997, doi:10.1109/38.610204
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