Mastering 3DCG technology requires various knowledge and skills such as 3D geometry, graphics programming, and interface design [1], Cultivating such knowledge and practical skills is a difficult issue for everyone. Whereas many technical books and related web pages [2] are available for studying the details of the technology, it is difficult for understanding geometrical structures and rendering processes of 3D objects m static figures and images depicted in the textbooks. The books and web pages tend to use rather simplified figures for clear explanations. Such simple examples are too far-reached from practical 3D models used in many commercial products like 3D movies and games. A gap between the example models and the practical contents could be a factor for discouraging the users in learning the 3DCG technology.