A new free-form deformation through the control of parametric surfaces

A new free-form deformation method is presented in this paper. The deformation of an object is achieved by attaching it to two parametric surfaces, namely the shape surface S(combining right arrow above) (u, v) and the height surface H(combining right arrow above)(u, v). A control point or vertex of the object is projected onto the shape surface along its normal and a correspondence between the point and its projection on the shape surface is established. The point is then embedded into the parametric space defined by the shape surface. By regarding the height surface as a displacement function, the directed distance from the sample point to its projection on the shape surface can be further adjusted. The proposed method is independent of the representation of the underlying object. Experimental results show that the method is intuitive, easy to control and fast to run.