 
     /**
      *  Constructor.
+     *  @param byteCode Compiled Pixel Bender byte code as ByteArray or Class.
      */ 
     public function ShaderFilter(byteCode:*=null)  
     {  

    private var _topExtension:Number = 0.0;

    /**
     *  @copy flash.filters.ShaderFilter#topExtension()
     */
    public function get topExtension():Number
    {

        if (_shader)
        {
            _shader.precisionHint = _precisionHint ? 
                _precisionHint : _shader.precisionHint;
            instance = new flash.filters.ShaderFilter(_shader);
            instance.bottomExtension = _bottomExtension;
            instance.topExtension = _topExtension;
