Cros, FredericBrock, Philip J.2015-10-052015-10-0519881017-4656https://doi.org/10.2312/egtp.19881035This paper presents a new method for providing an interactive local control on 3-D curves and surfaces. The possibility of interacting directly on the vector tangent to the curve at each control point (e.g. changing its magnitude and direction) gives the user a more intuitive control for shaping a curve than if he has to manipulate "abstract" parameters (like bias or tension). This technique is based on the use of Cardinal-splines and can also provide a means to obtain local control on surfaces.10.2312/egtp.19881035