说明：  Vtk，（visualization toolkit）是一个开源的免费软件系统，主要用于三维计算机图形学、图像处理和可视化。Vtk是在面向对象原理的基础上设计和实现的，它的内核是用C++构建的，包含有大约250,000行代码，2000多个类，还包含有几个转换界面，因此也可以自由的通过Java，Tcl/Tk和Python各种语言使用vtk。
(VTK (Visualization Toolkit) is an open source free software system, mainly used in 3D computer graphics, image processing and visualization. VTK is designed and implemented on the basis of object-oriented principle. Its kernel is built with C + +, which contains about 250000 lines of code, more than 2000 classes and several transformation interfaces. Therefore, VTK can be freely used in Java, TCL / TK and python languages.)