Institute of Mathematics and Informatics Bulgarian Academy of Sciences
Abstract
This article goes into the development of NURBS models of
quadratic curves and surfaces. Curves and surfaces which could be represented
by one general equation (one for the curves and one for the surfaces) are
addressed. The research examines the curves: ellipse, parabola and hyperbola,
the surfaces: ellipsoid, paraboloid, hyperboloid, double hyperboloid,
hyperbolic paraboloid and cone, and the cylinders: elliptic, parabolic and
hyperbolic. Many real objects which have to be modeled in 3D applications
possess specific features. Because of this these geometric objects have been
chosen. Using the NURBS models presented here, specialized software modules (plug-ins) have been developed for a 3D graphic system. An analysis of their implementation and the primitives they create has been performed
