Abstract: Visual simulation of plant stems is of great significance for recognizing plant structure and improving realistic of plants.In order to simulate the external morphology of crop stalks，a Ball B-spline based method has been proposed.Firstly，3-dimension data points can be gotten by 3D scanner or digitizer.Then centerline and contour line can be resolved according to different B-spline base function.Finally，the normal vector can be used in order to simulate the bend of branches.Visualization model of pepper，cucumber and corn have been gotten by different forms of Ball B-spline.Besides，the algorithm has been improved for arbitrary shape during the modeling of corn.The experimental results show that this method not only can simulate the plant stalk with the degree of bending and many details but also can be used for many kinds of plant and has a relatively large value of certain prospects.

Key words: visualization, ball B-spline, stalk

摘要： 植物茎杆的可视化模拟对认知植物骨架结构及提高植株真实感具有重要意义。为模拟作物茎秆的外部形态，提出基于球B样条的植物茎杆模拟方法。首先利用数字化仪或三维扫描仪获取作物的真三维数据，然后根据不同作物的特点灵活选用样条基函数计算得到中轴线，并根据中轴线确定轮廓线，最后根据枝干的弯曲情况确定各点轮廓线的法向。文中利用不同表达形式的球B样条实现了辣椒、黄瓜、玉米三种作物的茎秆可视化模拟，并在玉米的模型中将球B样条推广到了任意轮廓外形的作物形态研究。实验表明，该方法得到的模型能够比较真实地反映作物茎杆的弯曲程度及诸多细节，适用于多种作物，具有一定的应用前景。

关键词: 可视化, 球B样条, 茎秆