A stereoscopic drawing program is described which permits the user to display and manipulate quadric surfaces. The quadric surfaces are the 3-dimensional relatives of the ellipse, parabola and hyperbola and include ellipsoids, hyperboloids of one sheet, hyperboloids of two sheets, elliptic cones, elliptic paraboloids, and hyperbolic paraboloids. These surfaces have both implicit and parametric representations. A 3-button mouse is used to create and manipulate the surfaces. Rubber-banding can be used to define the surface and three dimensional transformations of the surface including scaling, rotation and translation are defined by mouse movement. A goal is to maintain a consistent and intuitive method of control for these surfaces, using techniques similar to those used in 2-dimensional drawing systems. The tessellation, color and shading characteristics of a surface can be determined interactively by the user.
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