图形系统的设计与实现

介绍了现代许多软件中所需要的图形系统的设计与实现，该设计实现了绘制多种静态图形和多种类型的动画以及重要的撤销/恢复功能。它不仅实现了一般图形系统要求的功能，而且由于设计本身是按照现代软件工程的面向对象的思想的设计，具有很好的层次性，易理解性、具有十分优良的封装性和扩展性。首先介绍了整体设计的框架，再通过UML静态类图详述了几个关键类的设计，最后用UML序列图来表达各个类之间的交互关系。

Design and Implementation of Graphic System

In order to meet the need of graphic system in many modern softwares, a good design and implementation of graphic system is proposed. This design can draw many kind of static diagrams and dynamic diagrams, and have important undo and redo function. This design not only implements the function very well needed by generic graphic system, but also has good hierarchy, understandability, encapsulation and extensibility in terms of modern software engineering thinking. Firstly, the whole design frame is introduced, and then several key classes are presented by UML class diagram, at last the interaction is presented by UML interaction diagram.