Geometry Objects - Interactive Web-Based Virtual Reality with Java 3D - page 44

Figure 15. Second code segment of DiamondTriangleArray.java

39. private Geometry Tri3Geometry()
40. {

41. //Triangle 3

42. TriangleArray Tri3 = new TriangleArray (vertex, TriangleArray.COORDINATES);

43. Tri3.setCoordinate(0, new Point3f(0.0f,0.8f,0.0f));

44. Tri3.setCoordinate(1, new Point3f(0.0f,0.0f,-0.5f));

45. Tri3.setCoordinate(2, new Point3f(-0.5f,0.0f,0.0f));

46. return Tri3;

47. }

48.

49. private Geometry Tri4Geometry()

50. {

51. //Triangle 4

52. TriangleArray Tri4 = new TriangleArray (vertex, TriangleArray.COORDINATES);

53. Tri4.setCoordinate(0, new Point3f(0.0f,0.8f,0.0f));

54. Tri4.setCoordinate(1, new Point3f(-0.5f,0.0f,0.0f));

55. Tri4.setCoordinate(2, new Point3f(0.0f,0.0f,0.5f));

56. return Tri4;

57. }

58. //Bottom

59. private Geometry Tri5Geometry()

60. {

61. //Triangle 5

62. TriangleArray Tri5 = new TriangleArray (vertex, TriangleArray.COORDINATES);

63. Tri5.setCoordinate(0, new Point3f(0.0f,-0.8f,0.0f));

64. Tri5.setCoordinate(1, new Point3f(0.5f,0.0f,0.0f));

65. Tri5.setCoordinate(2, new Point3f(0.0f,0.0f,0.5f));

66. return Tri5;

67. }
68.
69.

private Geometry Tri6Geometry()

70. {

71. //Triangle 6

72. TriangleArray Tri6 = new TriangleArray (vertex, TriangleArray.COORDINATES);

73. Tri6.setCoordinate(0, new Point3f(0.0f,-0.8f,0.0f));

74. Tri6.setCoordinate(1, new Point3f(0.0f,0.0f,-0.5f));

75. Tri6.setCoordinate(2, new Point3f(0.5f,0.0f,0.0f));

76. return Tri6;

77. }

More complicated objects may instead be built more efficiently using GeometryS-
tripArray, which is an abstract class and includes LineStripArray, TriangleStripArray and
TriangleFanArray. Firgure 17 illustrates the basic shapes that can be constructed under these
classes, while Figure 18 shows some typical application graphics that can be generated.