Databases Reference
In-Depth Information
Figure 1: The current VWDB system architecture
schema definition language, and in section 4 we describe how to design and
implement a VWDB multi-modal database language. Section 5 concludes this paper.
2
The VWDB System
2.1
Prototyping
The VWDB is currently being developed at Ochanomizu University by integrating
a VR system and an object-oriented database system. An object-oriented database
system was selected because objects in a virtual world are usually composite objects
and object- oriented database systems are much more efficient than relational
database systems for storing and manipulating composite objects. Another reason
for using an object-oriented database is that the message-passing paradigm of the
object orientation seems suitable for supporting the multi-modality that will be a
feature of user interactions with the VWDB. Figure 1 shows the current system
architecture of the VWDB, in which a VR system and an object-oriented database
system are connected via the Fast Ethernet. The architecture is scalable in the
sense that more than one VR system could be connected to an object- oriented
database system via a network, which would be necessary in order to realize a
distributed virtual environment (DVE) for collaborative work support.
Figure 2 shows a set of input and output devices for users to wear when using
the VWDB prototype system. By wearing an HMD (Figure 2-1), users can see the
virtual world in 3-D. The 3-D 6DOF mouse (Figure 2-2) enables users to move
from their current position in any of six directions, i.e., up, down, right, left,
forward, and backward, in the virtual world. A magnetic sensor (Figure 2-3) is
