Towards the Representation of Virtual Gymnasia Based On Multi-dimensional Information Integration - Advances in Image and Graphics Technologies - page 253

2.2.2 The Model of Other Space Elements
Besides the massive seats, other space elements of the virtual gymnasium such as
aisles, circular runaway, court, stand, goals, midline and borders also play important
roles in the improvement of the users' experience and should be modeled respective-
ly. That is, their distribution models, coding rules, generation algorithms, and identifi-
cation algorithms should be designed and implemented. As they are similar to the
counterpart of the seats, they are omitted here.

2.3 The Implementation of the Plan Model of the Virtual Gymnasium

The plan model of the virtual gymnasium is implemented on the platform of Micro-
soft Foundation Class (MFC) through the help of the Graphics Device Interfaces
(GDI) as depicted in Figure 2. The key is to solve the problem of the transformation
between the polar coordinate system and the screen coordinate system so as to “in-
stall” a great deal of seats in the space limited screen.

Fig. 2. The implemented plan model of the virtual gymnasium by MFC(a bird's-eye view)

In the above figure, all the seats, aisles and other space elements are modeled as
objects and are all identifiable and can be positioned. Therefore, it lays a solid foun-
dation for the seamless interaction between the plan model and the stealth model.
Furthermore, it is helpful to other advanced applications such as ticket-book.

3 The Building of the Stealth Model of the Virtual Gymnasium

Nowadays, there are two mainstream approaches for the three-dimensional modeling
[4]: Geometry-Based Modeling, Rendering (GBMR) and Image-Based Modeling and
Rendering (IBMR). The great advantage of GBMR is that the users can directly watch
the transformed screen pictures as the viewpoint changes; and its weakness is that it is
difficult to build the models. At the same time, the great advantage of IBMR is that it
is relatively easy to build the models; and its weakness is that the picture must be
redrawn when the stealth changes.