Multiple Views - Interactive Web-Based Virtual Reality with Java 3D - page 242

• Create a PhysicalEnvironment object and attach to the View.

• Attach the TransformGroup to view branch.

Note that the creation and use of a TransformGroup for attaching the ViewPlatform
is to ensure that the viewing angle or position can be changed by using the appropriate
transformation. The code segment in Figure 3 gives an example showing how the structure
of a SimpleUniverse object can be set up.

Figure 4. Code structure for multiple views

1. public class ViewModelApp extends JApplet implements ActionListener

2. {

3. public void main(String[] args)

4. { // main method to run the application, specify screen size

5. }

6.

7. public ViewModel()

8. { // constructor, calls createViewGraph() and createVirtualWorld() from VirtualWorld.java

9. }

10.
11. public void destroy()

12. { // destructor

13. }

14.
15. public BranchGraph createViewGraph()

16. { // uses ViewManager.java to format and insert captions; calls createViewPlatform()

17. }

18.
19. public TransformGroup createViewPlatform(Canvas3D canvas3D, int mode)

20. { // most of the settings on the view model made here; calls vpTransform3D

21. }

22.
23. public Transform3D vpTransform3D(int mode)

24. { // specify the orientation and position of the View Platform

25. }

26.
27. public void enableInteraction(BranchGroup viewRoot)

28. { // functionality for keyboard and mouse navigation in the virtual world

29. }

30.

31. public void createPanel(int mode)

32. { // adds control such as buttons and check boxes for interaction

33. }

34.
35. public void actionPerformed(ActionEvent e)

36. { // specify the changes to be made when a control element is clicked

37. }

38. }