Stage3D_Game_Programming:渲染3D模型

OBJ是文件，先来解释下OBJ文件。随便找一个OBJ文件，用文本查看：

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# Max2Obj Version 4.0 Mar 10th, 2001 # # object (null) to come ... # v -0.257 0.191 0.423 v -0.115 0.29 -0.068 v -0.237 0 -0.074 v -0.237 0.071 0.646 ... # 82 vertices vt 0.623 0.227 0 vt 0.615 0.53 0 vt 0.895 0.555 0 vt 0.825 0.246 0 vt 0.647 0.847 0 ... # 39 texture vertices f 1/1 2/2 3/3 f 3/3 4/4 1/1 f 2/2 5/5 6/6 f 6/6 3/3 2/2 ... # 142 faces

v:是模型的顶点信息 vt:是贴图的UV坐标 f:是定义面的顶点索引和顶点对应的UV坐标索引 清楚了OBJ文件里各种数据所代表的信息，接下来就是如何把数据传递给显卡渲染。 那么我们需要一个解析OBJ文件的类(代码比较简单，注释就省了)

 

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package com.parser {     import flash.utils.ByteArray;          public class OBJParser     {         private var _lines:Array;         private const LINE_FEED:String = String.fromCharCode(10);         private const SPACE:String = String.fromCharCode(32);         private var _scale:Number;         public function OBJParser(objfile:ByteArray,scale:Number = 1)         {             _scale = scale;             if(objfile)             {                 var lineStr:String = parserToStr(objfile);                 _lines = lineStr.split(LINE_FEED);                 var loop:uint = _lines.length;                 for(var i:uint = 0; i < loop; i++)                 {                     parseLine(_lines[i]);                 }             }           }           private const VERTEX:String = 'v';         private const UV:String = 'vt';         private const INDEX_DATA:String = 'f';         private function parseLine(lineStr:String):void         {             var data:Array = lineStr.split(SPACE);             if(!data.length)return;             var key:String = data[0];             var parseData:Array = data.slice(1);             switch(key)             {                 case VERTEX:                     parseVertex(parseData);                     break;                 case UV:                     parseUV(parseData);                     break;                 case INDEX_DATA:                     parseIndexData(parseData);                     break;             }         }           private var _vertices:Vector.<Number> = new Vector.<Number>();         private function parseVertex(data:Array):void         {             if(data[0] == '' || data[0] == " ")             {                 data = data.slice(1);             }             var loop:uint = data.length;             for(var i:uint = 0; i < loop; i++)             {                 var value:Number = Number(data[i]);                 _vertices.push(value*_scale);             }         }           private var _uvs:Vector.<Number> = new Vector.<Number>();         private function parseUV(data:Array):void         {             if(data[0] == '' || data[0] == " ")             {                 data = data.slice(1);             }             var loop:uint = 2;             for(var i:uint = 0; i < loop; i++)             {                 var value:Number = Number(data[i]);                 _uvs.push(value*_scale);             }         }           private const SLASH:String = "/";         private var _indexData:Vector.<uint> = new Vector.<uint>();         private var _vertexsData:Vector.<Number> = new Vector.<Number>();         private var _uvData:Vector.<Number> = new Vector.<Number>();         private var _faceIndex:uint;         private function parseIndexData(data:Array):void         {             var index:uint = 0;             while((data[index] == '') || (data[index] == ' '))index++;             var loop:uint = index+3;               var vertexIndex:int;             var uvIndex:int;             var normalIndex:int;             for(var i:uint = index; i < loop; i++)             {                 var triplet:String = data[i];                 var subdata:Array = triplet.split(SLASH);                 vertexIndex = int(subdata[0]) - 1;                 uvIndex     = int(subdata[1]) - 1;                   if(vertexIndex < 0) vertexIndex = 0;                 if(uvIndex < 0) uvIndex = 0;                   index = 3*vertexIndex;                 _vertexsData.push(_vertices[index + 0],                 _vertices[index + 1], _vertices[index + 2]);                   index = 2*uvIndex;                 _uvData.push(1-_uvs[index+0],1-_uvs[index+1]);             }             _indexData.push(_faceIndex+0,_faceIndex+1,_faceIndex+2);             _faceIndex += 3;         }           private function parserToStr(objFileByteArray:ByteArray):String         {             return objFileByteArray.readUTFBytes(objFileByteArray.bytesAvailable);         }           /**          * 顶点数据          * @return          *          */             public function get vertexsData():Vector.<Number>         {             return _vertexsData;         }           /**          * UV数据          * @return          *          */             public function get uvData():Vector.<Number>         {             return _uvData;         }           /**          * 索引数据          * @return          *          */             public function get indexData():Vector.<uint>         {             return _indexData;         }       } }

 

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有了顶点信息，uv信息和面的索引信息接下来就可以把这货渲染出来了。

 

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package {     import com.adobe.utils.AGALMiniAssembler;     import com.adobe.utils.PerspectiveMatrix3D;     import com.parser.OBJParser;       import flash.display.Bitmap;     import flash.display.BitmapData;     import flash.display.Sprite;     import flash.display.Stage3D;     import flash.display.StageAlign;     import flash.display.StageScaleMode;     import flash.display3D.Context3D;     import flash.display3D.Context3DProgramType;     import flash.display3D.Context3DTextureFormat;     import flash.display3D.Context3DVertexBufferFormat;     import flash.display3D.IndexBuffer3D;     import flash.display3D.Program3D;     import flash.display3D.VertexBuffer3D;     import flash.display3D.textures.Texture;     import flash.events.Event;     import flash.geom.Matrix;     import flash.geom.Matrix3D;     import flash.geom.Vector3D;     import flash.utils.ByteArray;       [SWF(width='800',height='600',backgroundColor='0x333333',frameRate="60")]         public class GameTest extends Sprite     {         [Embed (source = "art/spaceship.obj",         mimeType = "application/octet-stream")]         private var objData:Class;           [Embed (source = "art/spaceship_texture.jpg")]         private var TextureBitmap:Class;         private var textureData:Bitmap = new TextureBitmap();           private var _stage3D:Stage3D;         private var _context3D:Context3D;         private const sw:uint = 700;         private const sh:uint = 500;           private var _objParser:OBJParser;         //顶点缓冲 存储顶点信息         private var _vertexBuffer:VertexBuffer3D;         //顶点缓冲 存储UV信息         private var _uvBuffer:VertexBuffer3D;         //顶点索引         private var _indexBuffer:IndexBuffer3D;         private var _texture:Texture;         private var _textureSize:uint = 512;         private var _projectionmatrix:PerspectiveMatrix3D;         private var _viewmatrix:Matrix3D;         private var _modelmatrix:Matrix3D = new Matrix3D();         private var _modelViewProjection:Matrix3D = new Matrix3D();           private var _vertexShaderAssembler:AGALMiniAssembler;         private var _fragmentAssembler:AGALMiniAssembler;         private var _program:Program3D;           public function GameTest()         {             if(this.stage)             {                 init();             }else             {                 addEventListener(Event.ADDED_TO_STAGE,init);             }         }           private function init(e:Event = null):void         {             if(hasEventListener(Event.ADDED_TO_STAGE))removeEventListener(Event.ADDED_TO_STAGE,init);             this.stage.scaleMode = StageScaleMode.NO_SCALE;             this.stage.align = StageAlign.TOP_LEFT;             initStage3D();         }           private function initStage3D():void         {             _stage3D = this.stage.stage3Ds[0];             if(_stage3D)             {                 _stage3D.addEventListener(Event.CONTEXT3D_CREATE,onContext3DCreate);                 _stage3D.requestContext3D();             }         }           private function onContext3DCreate(e:Event):void         {             _context3D = _stage3D.context3D;             if(_context3D == null)             {                 throw new Error("无法创建Context3D");                 return;             }               _stage3D.x = (this.stage.stageWidth - sw)/2;             _stage3D.y = (this.stage.stageHeight - sh)/2;               _context3D.configureBackBuffer(sw,sh,1);             _context3D.clear(205,205,205);             _context3D.enableErrorChecking = true;             initData();             initShader();             this.stage.addEventListener(Event.ENTER_FRAME,onEnterFrame);         }           private function initData():void         {             var objdata:ByteArray = new objData() as ByteArray;             _objParser = new OBJParser(objdata);               var vertexCont:uint = _objParser.vertexsData.length/3;             _vertexBuffer = _context3D.createVertexBuffer(vertexCont,3);             _vertexBuffer.uploadFromVector(_objParser.vertexsData,0,vertexCont);               var uvCont:uint = _objParser.uvData.length/2;             _uvBuffer = _context3D.createVertexBuffer(uvCont,2);             _uvBuffer.uploadFromVector(_objParser.uvData,0,uvCont);               _context3D.setVertexBufferAt(0,_vertexBuffer,0,Context3DVertexBufferFormat.FLOAT_3);             _context3D.setVertexBufferAt(1,_uvBuffer,0,Context3DVertexBufferFormat.FLOAT_2);               var indexData:Vector.<uint> = _objParser.indexData;             _indexBuffer = _context3D.createIndexBuffer(indexData.length);             _indexBuffer.uploadFromVector(indexData,0,indexData.length);               _texture = _context3D.createTexture(_textureSize,_textureSize,Context3DTextureFormat.BGRA,false);             uploadTextureWithMipmaps(_texture,textureData.bitmapData);               _projectionmatrix = new PerspectiveMatrix3D();             _projectionmatrix.identity();             // 45 degrees FOV, 640/480 aspect ratio, 0.1=near, 100=far             _projectionmatrix.perspectiveFieldOfViewRH(                 45.0, sw / sh, 0.01, 100.0);               _viewmatrix = new Matrix3D();             // camera Matrix3D             _viewmatrix.identity();             // 移动镜头到(0,0,0)             _viewmatrix.appendTranslation(0,0,0);         }           private function initShader():void         {             _vertexShaderAssembler = new AGALMiniAssembler();             _vertexShaderAssembler.assemble(Context3DProgramType.VERTEX,                 "m44 op, va0, vc0\n" +                 "mov v0, va0\n" +                 "mov v1, va1\n");               _fragmentAssembler= new AGALMiniAssembler();             _fragmentAssembler..assemble                 (                     Context3DProgramType.FRAGMENT,                      "tex ft0, v1, fs0 <2d,linear,repeat,miplinear>\n"+                     "mov oc, ft0\n"                 );               _program = _context3D.createProgram();             _program.upload(_vertexShaderAssembler.agalcode,_fragmentAssembler.agalcode);             _context3D.setTextureAt(0,_texture);                        _context3D.setProgram(_program);         }           private var _t:Number = 0;         private function onEnterFrame(e:Event):void         {             _context3D.clear(0,0,0,.7);             _t += 2.0;             _modelmatrix.identity();             //旋转模型             _modelmatrix.appendRotation(_t*1.0, Vector3D.Y_AXIS);             _modelmatrix.appendRotation(_t*-0.2, Vector3D.X_AXIS);             _modelmatrix.appendRotation(_t*0.3, Vector3D.Y_AXIS);             _modelmatrix.appendTranslation(-0.4, 0, -5);               _modelViewProjection.identity();             _modelViewProjection.append(_modelmatrix);             _modelViewProjection.append(_viewmatrix);             _modelViewProjection.append(_projectionmatrix);               _context3D.setProgramConstantsFromMatrix(Context3DProgramType.VERTEX, 0, _modelViewProjection, true );             //绘制模型             _context3D.drawTriangles(_indexBuffer, 0, _objParser.indexData.length/3);             //呈现至屏幕             _context3D.present();         }           /**          * Mipmap          * @param dest          * @param src          *          */             private function uploadTextureWithMipmaps(dest:Texture, src:BitmapData):void         {             var ws:int = src.width;             var hs:int = src.height;             var level:int = 0;             var tmp:BitmapData;             var transform:Matrix = new Matrix();               tmp = new BitmapData(src.width, src.height, true, 0);               while ( ws >= 1 && hs >= 1 )             {                 tmp.draw(src, transform, null, null, null, true);                 dest.uploadFromBitmapData(tmp, level);                 transform.scale(0.5, 0.5);                 level++;                 ws >>= 1;                 hs >>= 1;                 if (hs && ws)                 {                     tmp.dispose();                     tmp = new BitmapData(ws, hs, true, 0x00000000);                 }             }             tmp.dispose();         }       } }