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When a new object is inserted into the scene, it gets a unique and 
distinguished name. This name is very important, since it is used 
from the internal scripter to identify the object. It is the parameter 
that is used to query the database for additional information about 
the object and it is displayed in objects properties Inspector. 
3.2 Viewing and changing objects properties 
It is possible, in real time, to view and change almost all the 
properties of an object (or model). This is done using the Objects 
Inspector panel in the Control Room, where all objects and their 
properties are displayed. For example, the position, rotation 
vectors, scale, colour or visibility of any object can be change. 
The number of the properties depends of the object's type. The 
only thing that cannot be changed interactively is the geometry of 
the object, although this can be done using scripts. 
3.3 Moving and rotating 
Moving and rotating inside scene is achieved using the PC's 
keyboard and mouse or joystick. Moving forward and backward, 
turning and strafing left and right, going up and down (using 
mouse wheel) has already implemented, while different motion 
behaviours (e.g. head up/down) are under construction. Motion 
and rotation speeds are not fixed and can be changed in real-time. 
Also, motion can be done using two different methods, walk or 
flight. 
The whole scene or a specific object that participates in scene can 
interactively be rotated in order to be viewed from several 
perspectives. A later restoration of the scene to its original 
position is possible. Rotation is achieved using the mouse. 
3.4 Further interaction 
Except for the rotation and properties changing, further 
interaction between viewer and scene can be achieved, with or 
without scripting. For example, it is possible to select an object, 
to query a database about the object and display an image, play a 
video file or a sound that is linked with the object. Also, a script 
can be run automatically in order to automatically change any 
properties of the object or even to replace this object with 
another. The action that will be selected is left to whom will make 
the presentation. 
3.5 Database connectivity 
In order to connect OpenView with a database, the database must 
be "published" to ODBC. OpenView "talks? to database using 
SQL queries. This way, it is irrelevant if the database is in Oracle, 
Access or in any other format. 
OpenView uses a smart interface that allows the viewer to select 
the proper table and a connection field, from all available 
databases, tables and fields that are published to ODBC. Also, it 
allows the viewer to select only the wanted fields from the 
selected table. This connectivity can be done at any time; 
additionally, it can switch to another database or table during 
presentation. For convenience, all database settings can be stored 
into files and can be loaded when needed. 
Every time database info is needed about an object, OpenView 
creates an SQL query and passes the name of the selected object 
as a parameter to the connection field in order to find the specific 
record from the selected table. This task is done in the 
background, so it is invisible to viewer. Then the results are 
displayed to both left and right windows in order to have 
stereoscopic view of the info. 
3.6 Scripting support 
Seripting support is OpenView's most powerful component and is 
based on “Script Studio", from Tmssoftware. The script language 
that currently supported is *object pascal * while Visual Basic is 
in the way. 
Jsing scripts, the viewer is able to access every scene component, 
to change any of its properties, to move or rotate it etc. Actually, 
it is left on the fantasy to whom prepares the presentation what 
the script will do. 
For example, using the script below, a new object is entered to 
the scene 
  
Axis:=TmyGLAxis.Create(ControlForm); //create the object 
Axis. Name:—'Axis1'; //Name for scripter and Inspector 
ObjectsCube.AddChild(Axis); //put axis to ObjectsCube 
Axis.valid: true; // Enable axis 
Axis.RememberMe; // Set axis visible to scripter 
Axis. Position.SetPoint(3,3,3); 
  
  
  
while the following one (can be as part of the above script or 
standalone) rotates and moves the already loaded object 
  
For i:=0 to 5 do begin 
Axis! Position. SetPoint(i, ii); 
AxisCubel.pitchAngle: —i*3; 
sleep(100); 
processMessages; 
end; 
  
  
  
Actually, there are very few things that cannot be done using 
scripting. 
3.7 Producing Stereo Pairs 
Stereo pair production is done in a background process, forced to 
produce pairs as fast as the combination of the CPU and the 
graphics card allows. OpenView uses three cameras when 
running. The first (central camera) displays its contents on the 
Control Room. The other two (called “left eye” and “right eye”) 
are responsible to create the stereo pairs of images. All three 
cameras together are called the “Head”. Rotation of the “head” 
rotates all three cameras at once, The position of the two cameras 
is not fixed but floated. Even the two cameras lie on the same line 
that passes from the center of the central camera, their distance 
can be change. This is done because, most of the times, different 
scenes need different "eye distances". 
There are a couple ways of setting the virtual cameras and 
rendering the stereo pairs: toe-in and off-axis projections (Burke, 
1999). The toe-in projection (Fig. 2b) is easier to be implemented 
(just set the two virtual cameras focus at the same point) but has