木叶沙子

(转)Stage3D程序的基本步骤

2014-07-29 19:02:00

原文：http://www.flashache.com/2012/10/31/stage3d-program-basic-steps/ 作者：flashche

本月24号《flash开发者大会》，我选择了《AGAL程序设计》这么一个比较难讲的主题。这么一个相对比较小众的主题，在开发者大会这种需要顾虑到所有人的一个场合下讲，如何选择切入点是很重要的。说起来要跑通一个基础的Stage3D的程序，有很多步骤，就就比较难解释了，短短的40分钟要让全场大部分人都理解可以说是基本不可能，所以肯定不可能详细阐述这块的细节。当然，如果真能做到这点的话那就更棒了。所以决定在这整理一下完成一个Stage3D项目的基本开发流程，方便大家参考。附上的参考也是非常好的学习资料哦，:-)

flash开发者大会：http://www.wefdc.com/info

参考资料： Christer Kaitila, 《Adobe Flash 11 Stage3D(Molehill) Game Programming》, PACKT publishing Norbz’s Dev Blog, “Stage3D / AGAL from scratch”, http://blog.norbz.net/tutorials/ 7yue，“深入Stage3D”, http://t.cn/SbMKLo

因为比较详细，而且为了便于理解，所以这篇文章会比较长，不过主要是重复代码，所以不用担心，不会花费太长时间。

1、创建基础类

package
{
    import flash.display.Sprite;
    import flash.display.StageAlign;
    import flash.display.StageScaleMode;
    import flash.events.Event;

    [SWF(width="600",height="400",frameRate="60")]
    public class Stage3DBasic extends Sprite
    {
        public function Stage3DBasic()
        {
            if(stage != null) 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);
            stage.scaleMode = StageScaleMode.NO_SCALE;
            stage.align = StageAlign.TOP_LEFT;
        }
    }
}

为Stage3D设置这3个Frame rate，20/30/60

2、请求Context3D对象

package
{
    import flash.display.Sprite;
    import flash.display.StageAlign;
    import flash.display.StageScaleMode;
    import flash.display3D.Context3D;
    import flash.events.Event;

    [SWF(width="600",height="400",frameRate="60")]
    public class Stage3DBasic extends Sprite
    {
        private var _view_width:Number;
        private var _view_height:Number;

        private var _renderContext:Context3D;

        public function Stage3DBasic()
        {
            if(stage != null) 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);
            stage.scaleMode = StageScaleMode.NO_SCALE;
            stage.align = StageAlign.TOP_LEFT;

            _view_width = stage.stageWidth;
            _view_height = stage.stageHeight;

            stage.stage3Ds[0].addEventListener(Event.CONTEXT3D_CREATE, onContext3DCreate);
            stage.stage3Ds[0].requestContext3D();
        }

        private function onContext3DCreate(e:Event):void
        {
            _renderContext = stage.stage3Ds[0].context3D;
        }
    }
}

3、设置Context3D Display Buffer

package
{
    import flash.display.Sprite;
    import flash.display.StageAlign;
    import flash.display.StageScaleMode;
    import flash.display3D.Context3D;
    import flash.events.Event;

    [SWF(width="600",height="400",frameRate="60")]
    public class Stage3DBasic extends Sprite
    {
        private var _view_width:Number;
        private var _view_height:Number;

        private var _renderContext:Context3D;

        public function Stage3DBasic()
        {
            if(stage != null) 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);
            stage.scaleMode = StageScaleMode.NO_SCALE;
            stage.align = StageAlign.TOP_LEFT;

            _view_width = stage.stageWidth;
            _view_height = stage.stageHeight;

            stage.stage3Ds[0].addEventListener(Event.CONTEXT3D_CREATE, onContext3DCreate);
            stage.stage3Ds[0].requestContext3D();
        }

        private function onContext3DCreate(e:Event):void
        {
            _renderContext = stage.stage3Ds[0].context3D;
            _renderContext.configureBackBuffer(_view_width, _view_height, 0, true);
        }
    }
}

4、初始化模型数据

package
{
    import flash.display.Sprite;
    import flash.display.StageAlign;
    import flash.display.StageScaleMode;
    import flash.display3D.Context3D;
    import flash.events.Event;

    [SWF(width="600",height="400",frameRate="60")]
    public class Stage3DBasic extends Sprite
    {
        private var _view_width:Number;
        private var _view_height:Number;

        private var _renderContext:Context3D;

        private var _meshVertexData:Vector.<Number>;
        private var _meshInexData:Vector.<uint>;

        public function Stage3DBasic()
        {
            if(stage != null) 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);
            stage.scaleMode = StageScaleMode.NO_SCALE;
            stage.align = StageAlign.TOP_LEFT;

            _view_width = stage.stageWidth;
            _view_height = stage.stageHeight;

            stage.stage3Ds[0].addEventListener(Event.CONTEXT3D_CREATE, onContext3DCreate);
            stage.stage3Ds[0].requestContext3D();
        }

        private function onContext3DCreate(e:Event):void
        {
            _renderContext = stage.stage3Ds[0].context3D;
            _renderContext.configureBackBuffer(_view_width, _view_height, 0, true);

            initData();
        }

        private function initData():void
        {
            _meshVertexData = Vector.<Number>([
                    //X,  Y,     Z,  r, g, b
                    -0.3, -0.3,  0,  1, 0, 0,
                    0,    0.3,   0,  0, 1, 0,
                    0.3, -0.3,   0,  0, 0, 1
                ]);
            _meshInexData = Vector.<uint>([
                    0, 1, 2
                ]);
        }
    }
}

为了简单起见，定义的是一个三角形，可以看到两个数据，一个是meshVertexData，定义了每个定点的位置，和颜色值，一共三个点，每个点包含了6个数据，分别是x, y, z和r, g, b。meshVertexData包含了三个这样的数据。然后是meshIndexData，定义了链接这些定点的顺序，0， 1， 2，即按照顺序链接这三个定点，有点像小时候玩的连线游戏，是不是很简单就能理解了 :D

5、创建顶点缓冲和索引缓冲，并上传数据

package
{
    import flash.display.Sprite;
    import flash.display.StageAlign;
    import flash.display.StageScaleMode;
    import flash.display3D.Context3D;
    import flash.display3D.IndexBuffer3D;
    import flash.display3D.VertexBuffer3D;
    import flash.events.Event;

    [SWF(width="600",height="400",frameRate="60")]
    public class Stage3DBasic extends Sprite
    {
        private var _view_width:Number;
        private var _view_height:Number;

        private var _renderContext:Context3D;

        private var _meshVertexData:Vector.<Number>;
        private var _meshInexData:Vector.<uint>;

        private var _vertexBuffer:VertexBuffer3D;
        private var _indexBuffer:IndexBuffer3D;

        public function Stage3DBasic()
        {
            if(stage != null) 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);
            stage.scaleMode = StageScaleMode.NO_SCALE;
            stage.align = StageAlign.TOP_LEFT;

            _view_width = stage.stageWidth;
            _view_height = stage.stageHeight;

            stage.stage3Ds[0].addEventListener(Event.CONTEXT3D_CREATE, onContext3DCreate);
            stage.stage3Ds[0].requestContext3D();
        }

        private function onContext3DCreate(e:Event):void
        {
            _renderContext = stage.stage3Ds[0].context3D;
            _renderContext.configureBackBuffer(_view_width, _view_height, 0, true);

            initData();

            _vertexBuffer = _renderContext.createVertexBuffer(_meshVertexData.length / 6, 6);
            _vertexBuffer.uploadFromVector(_meshVertexData, 0, _meshVertexData.length / 6);

            _indexBuffer = _renderContext.createIndexBuffer(_meshInexData.length);
            _indexBuffer.uploadFromVector(_meshInexData, 0, _meshInexData.length);
        }

        private function initData():void
        {
            _meshVertexData = Vector.<Number>([
                    //X,  Y,     Z,  r, g, b
                    -0.3, -0.3,  0,  1, 0, 0,
                    0,    0.3,   0,  0, 1, 0,
                    0.3, -0.3,   0,  0, 0, 1
                ]);
            _meshInexData = Vector.<uint>([
                    0, 1, 2
                ]);
        }
    }
}

createVertexBuffer，传入的几个定点，以及每个定点包含的数据量。根据现有demo定义的meshVertexData，一共有meshVertexData.lenght/ 6个顶点，其实也就是3个，然后每个定点包含了:x,y,z,r,g,b，6个数据。

6、编译Vertex Shader

package
{
    import com.adobe.utils.AGALMiniAssembler;

    import flash.display.Sprite;
    import flash.display.StageAlign;
    import flash.display.StageScaleMode;
    import flash.display3D.Context3D;
    import flash.display3D.Context3DProgramType;
    import flash.display3D.IndexBuffer3D;
    import flash.display3D.VertexBuffer3D;
    import flash.events.Event;
    import flash.utils.ByteArray;

    [SWF(width="600",height="400",frameRate="60")]
    public class Stage3DBasic extends Sprite
    {
        private var _view_width:Number;
        private var _view_height:Number;

        private var _renderContext:Context3D;

        private var _meshVertexData:Vector.<Number>;
        private var _meshInexData:Vector.<uint>;

        private var _vertexBuffer:VertexBuffer3D;
        private var _indexBuffer:IndexBuffer3D;

        private var _vertexShader:ByteArray;

        public function Stage3DBasic()
        {
            if(stage != null) 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);
            stage.scaleMode = StageScaleMode.NO_SCALE;
            stage.align = StageAlign.TOP_LEFT;

            _view_width = stage.stageWidth;
            _view_height = stage.stageHeight;

            stage.stage3Ds[0].addEventListener(Event.CONTEXT3D_CREATE, onContext3DCreate);
            stage.stage3Ds[0].requestContext3D();
        }

        private function onContext3DCreate(e:Event):void
        {
            _renderContext = stage.stage3Ds[0].context3D;
            _renderContext.configureBackBuffer(_view_width, _view_height, 0, true);

            initData();

            _vertexBuffer = _renderContext.createVertexBuffer(_meshVertexData.length / 6, 6);
            _vertexBuffer.uploadFromVector(_meshVertexData, 0, _meshVertexData.length / 6);

            _indexBuffer = _renderContext.createIndexBuffer(_meshInexData.length);
            _indexBuffer.uploadFromVector(_meshInexData, 0, _meshInexData.length);

            var vertexShaderAssembler:AGALMiniAssembler = new AGALMiniAssembler();
            _vertexShader = vertexShaderAssembler.assemble(
                    Context3DProgramType.VERTEX,
                    "mov op, va0\n" +
                    "mov v0, va1\n"
                );
        }

        private function initData():void
        {
            _meshVertexData = Vector.<Number>([
                    //X,  Y,     Z,  r, g, b
                    -0.3, -0.3,  0,  1, 0, 0,
                    0,    0.3,   0,  0, 1, 0,
                    0.3, -0.3,   0,  0, 0, 1
                ]);
            _meshInexData = Vector.<uint>([
                    0, 1, 2
                ]);
        }
    }
}

示例包含了两行AGAL代码，使用了同一个opcode：mov，第一行将va0(将保存位置信息）输出到op，然后第二行将保存了颜色信息的va1赋值给v0，这种寄存器保存的信息共享于vertex shader和fragment shader。

7、编译Fragment Shader

package
{
    import com.adobe.utils.AGALMiniAssembler;

    import flash.display.Sprite;
    import flash.display.StageAlign;
    import flash.display.StageScaleMode;
    import flash.display3D.Context3D;
    import flash.display3D.Context3DProgramType;
    import flash.display3D.IndexBuffer3D;
    import flash.display3D.VertexBuffer3D;
    import flash.events.Event;
    import flash.utils.ByteArray;

    [SWF(width="600",height="400",frameRate="60")]
    public class Stage3DBasic extends Sprite
    {
        private var _view_width:Number;
        private var _view_height:Number;

        private var _renderContext:Context3D;

        private var _meshVertexData:Vector.<Number>;
        private var _meshInexData:Vector.<uint>;

        private var _vertexBuffer:VertexBuffer3D;
        private var _indexBuffer:IndexBuffer3D;

        private var _vertexShader:ByteArray;
        private var _fragmentShader:ByteArray;

        public function Stage3DBasic()
        {
            if(stage != null) 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);
            stage.scaleMode = StageScaleMode.NO_SCALE;
            stage.align = StageAlign.TOP_LEFT;

            _view_width = stage.stageWidth;
            _view_height = stage.stageHeight;

            stage.stage3Ds[0].addEventListener(Event.CONTEXT3D_CREATE, onContext3DCreate);
            stage.stage3Ds[0].requestContext3D();
        }

        private function onContext3DCreate(e:Event):void
        {
            _renderContext = stage.stage3Ds[0].context3D;
            _renderContext.configureBackBuffer(_view_width, _view_height, 0, true);

            initData();

            _vertexBuffer = _renderContext.createVertexBuffer(_meshVertexData.length / 6, 6);
            _vertexBuffer.uploadFromVector(_meshVertexData, 0, _meshVertexData.length / 6);

            _indexBuffer = _renderContext.createIndexBuffer(_meshInexData.length);
            _indexBuffer.uploadFromVector(_meshInexData, 0, _meshInexData.length);

            var vertexShaderAssembler:AGALMiniAssembler = new AGALMiniAssembler();
            _vertexShader = vertexShaderAssembler.assemble(
                    Context3DProgramType.VERTEX,
                    "mov op, va0\n" +
                    "mov v0, va1\n"
                );

            var fragmentShaderAssembler:AGALMiniAssembler = new AGALMiniAssembler();
            _fragmentShader = fragmentShaderAssembler.assemble(
                    Context3DProgramType.FRAGMENT,
                    "mov oc, v0\n"
                );
        }

        private function initData():void
        {
            _meshVertexData = Vector.<Number>([
                    //X,  Y,     Z,  r, g, b
                    -0.3, -0.3,  0,  1, 0, 0,
                    0,    0.3,   0,  0, 1, 0,
                    0.3, -0.3,   0,  0, 0, 1
                ]);
            _meshInexData = Vector.<uint>([
                    0, 1, 2
                ]);
        }
    }
}

此处的fragment shader只是将v0保存的颜色信息给输出出来。

8、创建Program3D实例，并上传Shader

package
{
    import com.adobe.utils.AGALMiniAssembler;

    import flash.display.Sprite;
    import flash.display.StageAlign;
    import flash.display.StageScaleMode;
    import flash.display3D.Context3D;
    import flash.display3D.Context3DProgramType;
    import flash.display3D.IndexBuffer3D;
    import flash.display3D.Program3D;
    import flash.display3D.VertexBuffer3D;
    import flash.events.Event;
    import flash.utils.ByteArray;

    [SWF(width="600",height="400",frameRate="60")]
    public class Stage3DBasic extends Sprite
    {
        private var _view_width:Number;
        private var _view_height:Number;

        private var _renderContext:Context3D;

        private var _meshVertexData:Vector.<Number>;
        private var _meshInexData:Vector.<uint>;

        private var _vertexBuffer:VertexBuffer3D;
        private var _indexBuffer:IndexBuffer3D;

        private var _vertexShader:ByteArray;
        private var _fragmentShader:ByteArray;

        private var _shaderProgram:Program3D;

        public function Stage3DBasic()
        {
            if(stage != null) 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);
            stage.scaleMode = StageScaleMode.NO_SCALE;
            stage.align = StageAlign.TOP_LEFT;

            _view_width = stage.stageWidth;
            _view_height = stage.stageHeight;

            stage.stage3Ds[0].addEventListener(Event.CONTEXT3D_CREATE, onContext3DCreate);
            stage.stage3Ds[0].requestContext3D();
        }

        private function onContext3DCreate(e:Event):void
        {
            _renderContext = stage.stage3Ds[0].context3D;
            _renderContext.configureBackBuffer(_view_width, _view_height, 0, true);

            initData();

            _vertexBuffer = _renderContext.createVertexBuffer(_meshVertexData.length / 6, 6);
            _vertexBuffer.uploadFromVector(_meshVertexData, 0, _meshVertexData.length / 6);

            _indexBuffer = _renderContext.createIndexBuffer(_meshInexData.length);
            _indexBuffer.uploadFromVector(_meshInexData, 0, _meshInexData.length);

            var vertexShaderAssembler:AGALMiniAssembler = new AGALMiniAssembler();
            _vertexShader = vertexShaderAssembler.assemble(
                    Context3DProgramType.VERTEX,
                    "mov op, va0\n" +
                    "mov v0, va1\n"
                );

            var fragmentShaderAssembler:AGALMiniAssembler = new AGALMiniAssembler();
            _fragmentShader = fragmentShaderAssembler.assemble(
                    Context3DProgramType.FRAGMENT,
                    "mov oc, v0\n"
                );

            _shaderProgram = _renderContext.createProgram();
            _shaderProgram.upload(_vertexShader, _fragmentShader);

        }

        private function initData():void
        {
            _meshVertexData = Vector.<Number>([
                    //X,  Y,     Z,  r, g, b
                    -0.3, -0.3,  0,  1, 0, 0,
                    0,    0.3,   0,  0, 1, 0,
                    0.3, -0.3,   0,  0, 0, 1
                ]);
            _meshInexData = Vector.<uint>([
                    0, 1, 2
                ]);
        }
    }
}

9、设置Shader数据

package
{
    import com.adobe.utils.AGALMiniAssembler;

    import flash.display.Sprite;
    import flash.display.StageAlign;
    import flash.display.StageScaleMode;
    import flash.display3D.Context3D;
    import flash.display3D.Context3DProgramType;
    import flash.display3D.Context3DVertexBufferFormat;
    import flash.display3D.IndexBuffer3D;
    import flash.display3D.Program3D;
    import flash.display3D.VertexBuffer3D;
    import flash.events.Event;
    import flash.utils.ByteArray;

    [SWF(width="600",height="400",frameRate="60")]
    public class Stage3DBasic extends Sprite
    {
        private var _view_width:Number;
        private var _view_height:Number;

        private var _renderContext:Context3D;

        private var _meshVertexData:Vector.<Number>;
        private var _meshInexData:Vector.<uint>;

        private var _vertexBuffer:VertexBuffer3D;
        private var _indexBuffer:IndexBuffer3D;

        private var _vertexShader:ByteArray;
        private var _fragmentShader:ByteArray;

        private var _shaderProgram:Program3D;

        public function Stage3DBasic()
        {
            if(stage != null) 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);
            stage.scaleMode = StageScaleMode.NO_SCALE;
            stage.align = StageAlign.TOP_LEFT;

            _view_width = stage.stageWidth;
            _view_height = stage.stageHeight;

            stage.stage3Ds[0].addEventListener(Event.CONTEXT3D_CREATE, onContext3DCreate);
            stage.stage3Ds[0].requestContext3D();
        }

        private function onContext3DCreate(e:Event):void
        {
            _renderContext = stage.stage3Ds[0].context3D;
            _renderContext.configureBackBuffer(_view_width, _view_height, 0, true);

            initData();

            _vertexBuffer = _renderContext.createVertexBuffer(_meshVertexData.length / 6, 6);
            _vertexBuffer.uploadFromVector(_meshVertexData, 0, _meshVertexData.length / 6);

            _indexBuffer = _renderContext.createIndexBuffer(_meshInexData.length);
            _indexBuffer.uploadFromVector(_meshInexData, 0, _meshInexData.length);

            var vertexShaderAssembler:AGALMiniAssembler = new AGALMiniAssembler();
            _vertexShader = vertexShaderAssembler.assemble(
                    Context3DProgramType.VERTEX,
                    "mov op, va0\n" +
                    "mov v0, va1\n"
                );

            var fragmentShaderAssembler:AGALMiniAssembler = new AGALMiniAssembler();
            _fragmentShader = fragmentShaderAssembler.assemble(
                    Context3DProgramType.FRAGMENT,
                    "mov oc, v0\n"
                );

            _shaderProgram = _renderContext.createProgram();
            _shaderProgram.upload(_vertexShader, _fragmentShader);

            _renderContext.setVertexBufferAt(0, _vertexBuffer, 0, Context3DVertexBufferFormat.FLOAT_3);
            _renderContext.setVertexBufferAt(1, _vertexBuffer, 3, Context3DVertexBufferFormat.FLOAT_3);
        }

        private function initData():void
        {
            _meshVertexData = Vector.<Number>([
                    //X,  Y,     Z,  r, g, b
                    -0.3, -0.3,  0,  1, 0, 0,
                    0,    0.3,   0,  0, 1, 0,
                    0.3, -0.3,   0,  0, 0, 1
                ]);
            _meshInexData = Vector.<uint>([
                    0, 1, 2
                ]);
        }
    }
}

设置shader数据，分别设置了va0和va1。

10、设置当前的shader程序

package
{
    import com.adobe.utils.AGALMiniAssembler;

    import flash.display.Sprite;
    import flash.display.StageAlign;
    import flash.display.StageScaleMode;
    import flash.display3D.Context3D;
    import flash.display3D.Context3DProgramType;
    import flash.display3D.Context3DVertexBufferFormat;
    import flash.display3D.IndexBuffer3D;
    import flash.display3D.Program3D;
    import flash.display3D.VertexBuffer3D;
    import flash.events.Event;
    import flash.utils.ByteArray;

    [SWF(width="600",height="400",frameRate="60")]
    public class Stage3DBasic extends Sprite
    {
        private var _view_width:Number;
        private var _view_height:Number;

        private var _renderContext:Context3D;

        private var _meshVertexData:Vector.<Number>;
        private var _meshInexData:Vector.<uint>;

        private var _vertexBuffer:VertexBuffer3D;
        private var _indexBuffer:IndexBuffer3D;

        private var _vertexShader:ByteArray;
        private var _fragmentShader:ByteArray;

        private var _shaderProgram:Program3D;

        public function Stage3DBasic()
        {
            if(stage != null) 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);
            stage.scaleMode = StageScaleMode.NO_SCALE;
            stage.align = StageAlign.TOP_LEFT;

            _view_width = stage.stageWidth;
            _view_height = stage.stageHeight;

            stage.stage3Ds[0].addEventListener(Event.CONTEXT3D_CREATE, onContext3DCreate);
            stage.stage3Ds[0].requestContext3D();
        }

        private function onContext3DCreate(e:Event):void
        {
            _renderContext = stage.stage3Ds[0].context3D;
            _renderContext.configureBackBuffer(_view_width, _view_height, 0, true);

            initData();

            _vertexBuffer = _renderContext.createVertexBuffer(_meshVertexData.length / 6, 6);
            _vertexBuffer.uploadFromVector(_meshVertexData, 0, _meshVertexData.length / 6);

            _indexBuffer = _renderContext.createIndexBuffer(_meshInexData.length);
            _indexBuffer.uploadFromVector(_meshInexData, 0, _meshInexData.length);

            var vertexShaderAssembler:AGALMiniAssembler = new AGALMiniAssembler();
            _vertexShader = vertexShaderAssembler.assemble(
                    Context3DProgramType.VERTEX,
                    "mov op, va0\n" +
                    "mov v0, va1\n"
                );

            var fragmentShaderAssembler:AGALMiniAssembler = new AGALMiniAssembler();
            _fragmentShader = fragmentShaderAssembler.assemble(
                    Context3DProgramType.FRAGMENT,
                    "mov oc, v0\n"
                );

            _shaderProgram = _renderContext.createProgram();
            _shaderProgram.upload(_vertexShader, _fragmentShader);

            _renderContext.setVertexBufferAt(0, _vertexBuffer, 0, Context3DVertexBufferFormat.FLOAT_3);
            _renderContext.setVertexBufferAt(1, _vertexBuffer, 3, Context3DVertexBufferFormat.FLOAT_3);

            _renderContext.setProgram(_shaderProgram);
        }

        private function initData():void
        {
            _meshVertexData = Vector.<Number>([
                    //X,  Y,     Z,  r, g, b
                    -0.3, -0.3,  0,  1, 0, 0,
                    0,    0.3,   0,  0, 1, 0,
                    0.3, -0.3,   0,  0, 0, 1
                ]);
            _meshInexData = Vector.<uint>([
                    0, 1, 2
                ]);
        }
    }
}

11、渲染

package
{
    import com.adobe.utils.AGALMiniAssembler;

    import flash.display.Sprite;
    import flash.display.StageAlign;
    import flash.display.StageScaleMode;
    import flash.display3D.Context3D;
    import flash.display3D.Context3DProgramType;
    import flash.display3D.Context3DVertexBufferFormat;
    import flash.display3D.IndexBuffer3D;
    import flash.display3D.Program3D;
    import flash.display3D.VertexBuffer3D;
    import flash.events.Event;
    import flash.utils.ByteArray;

    [SWF(width="600",height="400",frameRate="60")]
    public class Stage3DBasic extends Sprite
    {
        private var _view_width:Number;
        private var _view_height:Number;

        private var _renderContext:Context3D;

        private var _meshVertexData:Vector.<Number>;
        private var _meshInexData:Vector.<uint>;

        private var _vertexBuffer:VertexBuffer3D;
        private var _indexBuffer:IndexBuffer3D;

        private var _vertexShader:ByteArray;
        private var _fragmentShader:ByteArray;

        private var _shaderProgram:Program3D;

        public function Stage3DBasic()
        {
            if(stage != null) 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);
            stage.scaleMode = StageScaleMode.NO_SCALE;
            stage.align = StageAlign.TOP_LEFT;

            _view_width = stage.stageWidth;
            _view_height = stage.stageHeight;

            stage.stage3Ds[0].addEventListener(Event.CONTEXT3D_CREATE, onContext3DCreate);
            stage.stage3Ds[0].requestContext3D();
        }

        private function onContext3DCreate(e:Event):void
        {
            _renderContext = stage.stage3Ds[0].context3D;
            _renderContext.configureBackBuffer(_view_width, _view_height, 0, true);

            initData();

            _vertexBuffer = _renderContext.createVertexBuffer(_meshVertexData.length / 6, 6);
            _vertexBuffer.uploadFromVector(_meshVertexData, 0, _meshVertexData.length / 6);

            _indexBuffer = _renderContext.createIndexBuffer(_meshInexData.length);
            _indexBuffer.uploadFromVector(_meshInexData, 0, _meshInexData.length);

            var vertexShaderAssembler:AGALMiniAssembler = new AGALMiniAssembler();
            _vertexShader = vertexShaderAssembler.assemble(
                    Context3DProgramType.VERTEX,
                    "mov op, va0\n" +
                    "mov v0, va1\n"
                );

            var fragmentShaderAssembler:AGALMiniAssembler = new AGALMiniAssembler();
            _fragmentShader = fragmentShaderAssembler.assemble(
                    Context3DProgramType.FRAGMENT,
                    "mov oc, v0\n"
                );

            _shaderProgram = _renderContext.createProgram();
            _shaderProgram.upload(_vertexShader, _fragmentShader);

            _renderContext.setVertexBufferAt(0, _vertexBuffer, 0, Context3DVertexBufferFormat.FLOAT_3);
            _renderContext.setVertexBufferAt(1, _vertexBuffer, 3, Context3DVertexBufferFormat.FLOAT_3);

            _renderContext.setProgram(_shaderProgram);

            addEventListener(Event.ENTER_FRAME, render);
        }

        private function render(e:Event):void
        {
            _renderContext.clear(0,0,0,0);
            _renderContext.drawTriangles(_indexBuffer);
            _renderContext.present();
        }

        private function initData():void
        {
            _meshVertexData = Vector.<Number>([
                    //X,  Y,     Z,  r, g, b
                    -0.3, -0.3,  0,  1, 0, 0,
                    0,    0.3,   0,  0, 1, 0,
                    0.3, -0.3,   0,  0, 0, 1
                ]);
            _meshInexData = Vector.<uint>([
                    0, 1, 2
                ]);
        }
    }
}

虽然只是一个三角，但是这正是stage3d底层开发的一个开端，虽然步骤看上去很多，而且不同的情况下这些步骤的细节会有所调整，但是掌握好这个demo才能继续接下来的内容。下一篇文章我将继续Stage3D的底层开发，使用uv贴图。尽请期待。