[]normalizedViewport修改问题

		/**

		*获取裁剪空间的视口。

		*@return 裁剪空间的视口。

		*/

		__getset(0,__proto,'normalizedViewport',function(){

			if (!this._viewportExpressedInClipSpace){

				var vp=this._viewport;

				var size=this.renderTargetSize;

				var sizeW=size.width;

				var sizeH=size.height;

				this._normalizedViewport.x=vp.x / sizeW;

				this._normalizedViewport.y=vp.y / sizeH;

				this._normalizedViewport.width=vp.width / sizeW;

				this._normalizedViewport.height=vp.height / sizeH;

			}

			return this._normalizedViewport;

			},function(value){

			if (value.x < 0 || value.y < 0 || (value.x+value.width)> 1 || (value.y+value.height)> 1)

				throw new Error("Camera: viewport size invalid.","value");

			this._viewportExpressedInClipSpace=true;

			this._normalizedViewport=value;

			this._calculateProjectionMatrix();

		});