主要讲述了世界坐标，以及各种裁剪算法，对于各种裁剪算法具有详细的描述和算法，同时列举了大量的实例，对于掌握各种裁剪方法有很好的帮助-The main story of the world coordinates, and a variety of cutting algorithm, for a variety of cutting algorithm and the algorithm described in detail, at the same time a large number o