An algorithm to improve parameterizations of rational Bezier surfaces using rational bilinear reparameterization

摘要

The parameterization of rational Bezier surfaces greatly affects rendering and tessellation results. The uniformity and orthogonality of iso-parametric curves are two key properties of the optimal parameterization. The only rational Bezier surfaces with uniform iso-parametric curves are bilinear surfaces, and the only rational Bezier surfaces with uniform and orthogonal iso-parametric curves are rectangles. To improve the uniformity and orthogonality of iso-parametric curves for general rational Bezier surfaces, an optimization algorithm using the rational bilinear reparameterizations is presented, which can produce a better parameterization with the cost of degree elevation. Examples are given to show the performance of our algorithm for rendering and tessellation applications.