Punctual constraint resolution and deformation path on NURBS

The Free From Deformations are the most spread methods to modify the shape of geometrical objects, described with vertices and faces. Many applications have been developed to extend this approach, allowing different constraint specifications or actions. It has also been adapted to deform subdivision or implicit surfaces. This paper introduces an improvement for NURBS surfaces, allowing a point picked on the surface to follow a curvilinear path. The principle of the method is to let the user choose a point on the NURBS surface and its destination location in space. Then, the deformation range and the curvilinear path from the constraint point to the displacement goal must be specified. The proposed process computes the deformation of the initial object to match a displacement constraint. In order to be applied on NURBS surfaces, the process uses the (u, v) parameters of the initial chosen point, but this computational step is hidden for the user.

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