There is such a depth of information about 3D-manipulation idioms that an entire chapter or even an entire book could be written about them. We will, thus, briefly address some of the broader issues of 3D object manipulation.

• 对三维操作习惯用法更深入的讨论可能需要整章，甚至整卷书的篇幅来描述，我们这里只简单地介绍三维操作的一般性问题。