截面轮廓曲线驱动的约束自由变形

Constrained Free Form Deformation Driven by Sectional Outline Curve

提出一种由二维截面轮廓曲线驱动三维网格模型变形的方法。以STL数据格式为研究对象,在进行拓扑重构的基础上,利用模型的拓扑信息,快速构建平面与三角网格模型相交的截面轮廓曲线,并用三次非均匀Bspline曲线表示。以曲线曲率分布为依据,在曲线上重新采样作为曲线编辑的型值点,在曲线形状修改满意后,以曲线修改前后型值点的位置作为约束,采样约束直接操作自由变形技术,使三维网格模型变形。该方法操作方便、实时直观、且不需构建轮廓曲线与网格模型顶点之间的映射关系。

A method that uses 2D sectional outline curve to drive 3D mesh model deformation was presented. STL data format was taken as research object. Based on topological reconstruction and using the topological information of the model, the sectional outline curve that intersects by plane and triangular meshes is efficiently constructed and is presented by cubic NURBS curve. The curve is resampled based on curvature distribution and the new points are made as data points for curve edit. When curve shape revision is satisfied, the positions of data points that before and after revision are taken as constrained conditions, and constrained direct manipu- lation of free form deformation are used to make triangular mesh modle deformtion. This method has advatages such as convient for manipulate, real-time and intuitive, and not necessary to build map relation between outline curve and vertex of mesh model.