DLO几何建模算法及其表面绘制

Geometrical Modeling Algorithm of DLO Based on B-Spline and Surface Rendering

基于B样条的DLO(deformable linear Dbject)几何算法计算量小,但目前的研究尚未解决多个指定点和表面绘制问题。提出采用双段三次开放B样条分段描述DLO中心线,成功解决了多个指定点问题;提出通过坐标变换建立DLO线框模型,利用线框模型顶点构建三角形面片,调用OpenGL函数库中的GL_POLYGON函数填充三角形面片,从而实现了DLO的表面绘制。实验和应用表明,上述算法的逼真度高,能够满足虚拟环境的真实感和实时性要求。

The geometrical nodeling algorithm of deformable linear object （DLO） based on B Spline consists of small amount of computation. However, the passing through mutiple specified points and the rendering of the surface haven＇t been studied. For the first problem, a new method was proposed, in which the DLO was described by seg ments, each segment centerline was described with two section three order open B spline. For the second prob lem, firstly, the DLO wireframe model was established by the coordinate transformation. Secondly, the triangular fac ets were built with the vertices of the wireframe model. Thirdly, the surface rendering was achieved by filling the tri angular facets with the function of GL_POLYGON in OpenGL library. Experiments and applications show that the al gorithm can meet the sense of reality and the real time requirement in virtual environment.