三维自由曲面形成浓淡图的研究

Research on Shaded Curve Graphics of Three Dimensional Freedom Surface

双Ｂｅｔａ样条曲面是由具有几何连续性的双Ｂｅｔａ样条曲线构成，本文从双Ｂｅｔａ样条曲线的基函数入手，给出了这种曲面的算法原理，以此为基础的曲面造型系统ＦＳＭＳ已经实现。本文介绍了ＦＳＭＳ系统采用的光照模型的算法和形成浓淡图的处理方法，并给出了应用实例。

The double Beta spline surface is composed of double Beta spline curves which have geometric connectivity.This paper first deals with the base function of double Beta spline curves.Second,it mainly gives the principle of algorithm of the double Beta spline surface.The FSMS (Freedom Surface Modelling System) is based on the surface.The purpose of the paper is to introduce the controlling method of double Beta spline surface by double parameters and the shaded curve graphics.The author has also given application examples.