An algorithm is proposed to give a global approximation of an implicit real plane algebraic
curve with rational quadratic B-spline curves. The algorithm consists of four steps: topology
determination, curve segmentation, segment approximation and curve tracing. Due to the
detailed geometric analysis, high accuracy of approximation may be achieved with a small
number of quadratic segments. The final approximation keeps many important geometric
features of the original curve such as the topology, convexity and sharp points. Our method …