Locally manipulating the geometry of curved surfaces

Interactive tools that can be used to edit a curved surface locally by altering its intrinsic geometric measures are described. The interface consists of two parts. The first uses graphic displays that illustrate specific characteristics of the surface. Users can isolate different types of curves on a surface. These curves yield unique information about the surface. The second part of the interface uses some of the specialized icons to interactively manipulate the surface itself. The methods can be used with many previously published techniques, and, because they are based on the intrinsic differential geometry of the surface, can be applied to all types of surfaces (parametric, implicit, algebraic, and so forth).<>