VB：顶点缓冲
IB: 顶点索引缓冲
三角形的顶点顺序决定了三角形是顺时针还是逆时针，从而决定了三角形在背面剔除的过程中是否会被剔除掉。
相关理论知识可以在前面的文章中找到更多的说明。
实现效果
主要代码
1 package
2 {
3 import com.adobe.utils.AGALMiniAssembler;
4 import com.adobe.utils.PerspectiveMatrix3D;
5
6 import flash.display.Sprite;
7 import flash.display.Stage3D;
8 import flash.display3D.Context3D;
9 import flash.display3D.Context3DProgramType;
10 import flash.display3D.Context3DVertexBufferFormat;
11 import flash.display3D.IndexBuffer3D;
12 import flash.display3D.Program3D;
13 import flash.display3D.VertexBuffer3D;
14 import flash.events.Event;
15 import flash.geom.Matrix3D;
16 import flash.geom.Vector3D;
17
18 /**
19 * @author smartqi
20 * @E-mail:
21 * 创建时间：2013-6-29 上午9:36:36
22 *
23 */
24 public class RectangleTest extends Sprite
25 {
26
27 private var context:Context3D;
28 private var vertexBuff:VertexBuffer3D;
29 private var indexBuff:IndexBuffer3D;
30 private var vertexData:Vector.<Number>;
31 private var indexData:Vector.<uint>;
32 private var shaderProgram:Program3D;
33 private var perspectiveMatrix:PerspectiveMatrix3D;
34 private var i:int;
35 private var sign:int = 1;
36 private const angleGap:Number = 20;
37 private var angle:Number = 0;
38 private var modelMatrix:Matrix3D;
39 private var viewMatrix:Matrix3D;
40 private var finalMatrix:Matrix3D;
41
42
43 public function RectangleTest()
44 {
45 var stage3d:Stage3D = stage.stage3Ds[0];
46 stage3d.addEventListener(Event.CONTEXT3D_CREATE,onContextCreate);
47 stage3d.requestContext3D();
48 }
49
50 private function onContextCreate(e:Event):void{
51 context = (e.target as Stage3D).context3D;
52 if(context == null) return;
53 context.enableErrorChecking = true; //允许进行错误检测，release版本应设置
54 context.configureBackBuffer(500,500,0); //设置显示区域的大小
55 setupVertexBuff(); //设置顶点缓冲
56 setupShaderProgram(); //设置shander
57 setupPerspectiveMatrix(); //设置投影矩阵
58 initMatrix();
59 addEventListener(Event.ENTER_FRAME,onEnterFrame);
60 }
61
62 private function setupVertexBuff():void{
63 vertexData = Vector.<Number>([
64 // x y z r g b
65 40, 40, -40, 1, 0, 0,
66 40, -40, -40, 0, 1, 0,
67 -40, -40, -40, 0, 0, 1,
68 -40, 40, -40, 1, 1, 1,
69 ]);
70
71 indexData = Vector.<uint>([0,1,2,0,2,3]);
72 vertexBuff = context.createVertexBuffer(4,vertexData.length/4);
73 vertexBuff.uploadFromVector(vertexData,0,4);
74 indexBuff = context.createIndexBuffer(6);
75 indexBuff.uploadFromVector(indexData,0,6);
76 context.setVertexBufferAt(0,vertexBuff,0,Context3DVertexBufferFormat.FLOAT_3);
77 context.setVertexBufferAt(1,vertexBuff,3,Context3DVertexBufferFormat.FLOAT_3);
78 }
79
80 private function setupShaderProgram():void{
81 var vertexProgram:AGALMiniAssembler = new AGALMiniAssembler();
82 vertexProgram.assemble(Context3DProgramType.VERTEX,
83 "m44 op,va0,vc0\n" +
84 "mov v1,va1\n");
85 var fragmentProgram:AGALMiniAssembler = new AGALMiniAssembler();
86 fragmentProgram.assemble(Context3DProgramType.FRAGMENT,
87 "mov oc,v1");
88 shaderProgram = context.createProgram();
89 shaderProgram.upload(vertexProgram.agalcode,fragmentProgram.agalcode);
90 context.setProgram(shaderProgram);
91 }
92
93 private function setupPerspectiveMatrix():void{
94 perspectiveMatrix = new PerspectiveMatrix3D();
95 perspectiveMatrix.perspectiveFieldOfViewRH(Math.PI*90/180,1,1,1000); //注意这里的角度使用的是弧度
96 }
97
98 private function initMatrix():void{
99 modelMatrix = new Matrix3D();
100 viewMatrix = new Matrix3D();
101 finalMatrix = new Matrix3D();
102 }
103
104 private function onEnterFrame(e:Event):void{
105 context.clear(0,0,0);
106 angle += angleGap;
107 modelMatrix.identity();
108 modelMatrix.prependRotation(angle,Vector3D.Z_AXIS); //绕着Z轴旋转物体，注意这里的角度使用的是角度
109 if(i>30){
110 sign = -1;
111 }
112 if(i<0){
113 sign = 1;
114 }
115 i += sign;
116 viewMatrix.identity();
117 viewMatrix.prependTranslation(0,0,-30 + i); //将相机向后移，使物体看起来变小了,将相机向前移，使物体看起来变大
118 finalMatrix.identity();
119 finalMatrix.append(modelMatrix);
120 finalMatrix.append(viewMatrix);
121 finalMatrix.append(perspectiveMatrix);
122 context.setProgramConstantsFromMatrix(Context3DProgramType.VERTEX,0,finalMatrix,true); //上传最终的顶点转换矩阵，注意这里最后一个参数为true
123 context.drawTriangles(indexBuff,0,2);
124 context.present();
125 }
126 }
127 }