Geometry Objects - Interactive Web-Based Virtual Reality with Java 3D - page 64

Figure 40. Code segment and result of Quad.java

Index 1 Index 2

Surface B
(Inward facing)

Surface A
(Outward facing)

Index 3

Index 4

1. public class Axis

2. {

3. private BranchGroup axisBG;

4.

5. public Axis()

6. {

7. axisBG = new BranchGroup();

8. IndexedQuadArray array =

9. new IndexedQuadArray(8, QuadArray.COORDINATES|QuadArray.COLOR_3,24);

10.
11. Point3f []pts = new Point3f[8];

12. pts[0] = new Point3f(0.25f, 0.25f, 0.25f); pts[1] = new Point3f(-0.25f, 0.25f, 0.25f);

13. pts[2] = new Point3f(0.25f, 0.25f, -0.25f); pts[3] = new Point3f(-0.25f, 0.25f, -0.25f);

14. pts[4] = new Point3f(0.5f, -0.5f, 0.5f); pts[5] = new Point3f(-0.5f, -0.5f, 0.5f);

15. pts[6] = new Point3f(0.5f, -0.5f, -0.5f); pts[7] = new Point3f(-0.5f, -0.5f, -0.5f);

16. int []indices = {0,2,3,1,4,5,7,6,0,4,6,2,1,3,7,5,1,5,4,0,2,6,7,3};

17. array.setCoordinates(0,pts);

18. array.setCoordinateIndices(0, indices);

19.
20. Color3f []color = new Color3f[8];

21. color[0] = new Color3f(1f, 0f, 1f); color[1] = new Color3f(1f, 0f, 0f);

22. color[2] = new Color3f(0f, 1f, 0f); color[3] = new Color3f(0f, 0f, 1f);

23. color[4] = new Color3f(0f, 1f, 1f); color[5] = new Color3f(1f, 1f, 0f);

24. color[6] = new Color3f(0.5f, 0.5f,0f); color[7] = new Color3f(1f, 1f, 1f);

25. int []colorIndices = {0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5};

26. array.setColors(0,color);

27. array.setColorIndices(0, colorIndices);

28. }

29.
30.

public BranchGroup getBG() return axisBG;

31. }

Indexedlinestriparray

The disadvantage of LineStripArray is, of course, that it is often necessary to repeat some
vertices as when a complicated solid object is to be rendered. This disadvantage is over-