基于VTK平台的一个例子，主要展示了非结构网格的绘制及人机交互的实现，点击四边形的周围的顶点，可以显示一条连接中心点的直线-An example of the platform based on VTK, the main show unstructured grid drawing and realization of human-computer interaction, click the quadrilateral around the vertex, you can display a

光斑绘图（两个舵机构成二自由度机械臂，控制激光在墙面上绘制直线、正方形、圆形、椭圆等图形）-Spot drawing (two servos constitute the two degrees of freedom manipulator, control the laser to draw a straight line on the wall, square, round, oval and other graphics)