Stage3d AGAL GPU处理照片 旧照片效果 sepia || pixelbender

package 
{
    import com.adobe.utils.AGALMiniAssembler;
    import com.bit101.components.HSlider;
    import com.bit101.components.PushButton;
    
    import flash.display.Bitmap;
    import flash.display.BitmapData;
    import flash.display.Loader;
    import flash.display.Sprite;
    import flash.display.Stage3D;
    import flash.display.StageAlign;
    import flash.display.StageScaleMode;
    import flash.display3D.Context3D;
    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.net.FileFilter;
    import flash.net.FileReference;
    import flash.utils.ByteArray;
    
    import net.hires.debug.Stats;
    
    /**
     * 借用了boycy815的代码框架
     * @author kenkozheng
     */
    [SWF(frameRate="60")]
    public class AGAL_Filter extends Sprite 
    {
        private const WIDTH:Number = 512;
        private const HEIGHT:Number = 512;
        
        //stage3d五巨头
        private var _stage3d:Stage3D;
        private var _context3d:Context3D;
        private var _program3d:Program3D;
        private var _index:IndexBuffer3D;
        private var _vertex:VertexBuffer3D;
        private var _texture:Texture;
        
        [Embed(source=("4.jpg"))]
        private var ImageSource:Class;
        
        private var _vertexProgram:String = "mov op, va0\n" +
                                        "mov v0, va1";            //传递给片段shader坐标值
        
        private var _fragmentProgram:String = "tex ft1, v0, fs0<2d,linear,nomip>\n" +
                                            "m44 ft2, ft1, fc1\n" +            //颜色变换
                                            "mul ft2, ft2, fc0.x\n" +        //效果图跟原图做multiply，向量float4 * float = float4，类似PixelBender
                                            "mul ft1, ft1, fc0.y\n" +
                                            "add ft2, ft2, ft1\n" +
                                            "mov oc, ft2";
        
        public function AGAL_Filter():void 
        {
            if (stage) init();
            else addEventListener(Event.ADDED_TO_STAGE, init);
        }
        
        private function init(e:Event = null):void 
        {
            stage.scaleMode = StageScaleMode.NO_SCALE;
            stage.align = StageAlign.TOP_LEFT;
            removeEventListener(Event.ADDED_TO_STAGE, init);
            _stage3d = stage.stage3Ds[0];
            _stage3d.addEventListener(Event.CONTEXT3D_CREATE, onCreate);
            _stage3d.requestContext3D();
            addChild(new Stats());
        }
        
        private function onCreate(e:Event):void
        {
            e.target.removeEventListener(Event.CONTEXT3D_CREATE, onCreate);
            
            _context3d = _stage3d.context3D;
            _context3d.enableErrorChecking = true;
            
            var agal:AGALMiniAssembler = new AGALMiniAssembler();
            
            var vp:ByteArray = agal.assemble("vertex", _vertexProgram);
            var fp:ByteArray = agal.assemble("fragment", _fragmentProgram);
            _program3d = _context3d.createProgram();
            _program3d.upload(vp, fp);
            _context3d.setProgram(_program3d);
            
            _context3d.configureBackBuffer(WIDTH, HEIGHT, 0, false);
            _context3d.setBlendFactors("one", "zero");
            _context3d.setCulling("back");
            
            //两个三角形拼成平面
            _index = _context3d.createIndexBuffer(6);
            _index.uploadFromVector(new<uint>[0, 1, 2, 0, 2, 3], 0, 6);
            
            _vertex = _context3d.createVertexBuffer(4, 4);
            //这是由于纹理的坐标原点是左上角，y轴向下，最大值为1最小值为0
            //而顶点的坐标原点则是在舞台中央，而且y轴向上，最大值为1最小值为-1
            //那么(-1,-1)点对应的纹理就是(0,1)
            _vertex.uploadFromVector(new<Number>[
                //x, y, u, v
                -1, -1, 0, 1,
                -1, 1, 0, 0,
                1, 1, 1, 0,
                1, -1, 1, 1], 0, 4);
            _context3d.setVertexBufferAt(0, _vertex, 0, "float2"); //xy坐标
            _context3d.setVertexBufferAt(1, _vertex, 2, "float2");    //uv坐标
            
            //纹理位图
            var bt:Bitmap = Bitmap(new ImageSource());
            var btmap:BitmapData = new BitmapData(WIDTH, HEIGHT);
            btmap.draw(bt);
            
            //上传纹理
            _texture = _context3d.createTexture(btmap.width, btmap.height, "bgra", false);
            _texture.uploadFromBitmapData(btmap);
            _context3d.setTextureAt(0, _texture);
            //multiple比例
            _context3d.setProgramConstantsFromVector("fragment", 0, new<Number>[1, 0, 0, 0]);
            //颜色矩阵
            _context3d.setProgramConstantsFromMatrix("fragment", 1, new Matrix3D(new <Number>[
                0.393, 0.768, 0.189, 0,
                0.349, 0.686, 0.168, 0,
                0.272, 0.534, 0.13, 0,
                0, 0, 0, 1
            ]));
            
            _context3d.clear(0, 0, 0, 0);
            _context3d.drawTriangles(_index);
            _context3d.present();
            
            start();
        }
        
        private function start():void
        {
            new PushButton(this, 282, 515, "change", onUpload);
            new HSlider(this, 392, 520, onBar).setSliderParams(0, 1, 1);
        }
        
        private function onBar(e:Event):void
        {
            var v:Number = e.currentTarget.value;
            _context3d.setProgramConstantsFromVector("fragment", 0, new<Number>[v, 1-v, 0, 0]);
            _context3d.clear(0, 0, 0, 0);
            _context3d.drawTriangles(_index);
            _context3d.present();
        }
        
        private function onUpload(e:Event):void
        {
            var fr:FileReference = new FileReference();
            fr.addEventListener(Event.SELECT, onSelect);
            fr.browse([new FileFilter("jpg/png", "*.jpg;*.png")]);
        }
        
        private function onSelect(e:Event):void
        {
            e.currentTarget.removeEventListener(Event.SELECT, onSelect);
            e.currentTarget.addEventListener(Event.COMPLETE, onComplete);
            e.currentTarget.addEventListener(Event.OPEN, function(e:Event):void { } );
            e.currentTarget.load();
        }
        
        private function onComplete(e:Event):void
        {
            e.currentTarget.removeEventListener(Event.COMPLETE, onComplete);
            var loader:Loader = new Loader();
            loader.contentLoaderInfo.addEventListener(Event.COMPLETE, loaderOnComplete);
            loader.loadBytes(e.currentTarget.data);
        }
        
        private function loaderOnComplete(e:Event):void
        {
            e.currentTarget.removeEventListener(Event.COMPLETE, loaderOnComplete);
            
            var btmap:BitmapData = new BitmapData(WIDTH, HEIGHT);
            var scale:Number = Math.max(WIDTH/e.currentTarget.loader.width, HEIGHT/e.currentTarget.loader.height);
            btmap.draw(e.currentTarget.loader, new Matrix(scale, 0, 0, scale), null, null, null, true);
            
            _texture.uploadFromBitmapData(btmap);
            
            _context3d.clear(0, 0, 0, 0);
            _context3d.drawTriangles(_index);
            _context3d.present();
        }
    }
    
}