 package weave.visualization.layers
 {
 	import flash.display.Bitmap;
-	import flash.display.BitmapData;
 	import flash.display.PixelSnapping;
-	import flash.geom.Point;
 	
 	import mx.core.UIComponent;
 	import mx.utils.NameUtil;

		// these bitmaps will be added as a children
 		protected const backgroundBitmap:Bitmap = new Bitmap(null, PixelSnapping.AUTO, true);
		protected const plotBitmap:Bitmap = new Bitmap(null, PixelSnapping.AUTO, true);
		protected const aggregateBitmap:Bitmap = new Bitmap(null, PixelSnapping.AUTO, true);

		// access the filters of the background layer only
		public function get backgroundFilters():Array 			 { return backgroundBitmap.filters;  }

		 */
		private function init():void
		{
			// generate a name for debugging
			name = NameUtil.createUniqueName(this);
			// default size = 100%,100%
			percentWidth = 100;
			percentHeight = 100;
			
			this.addChild(backgroundBitmap);
			this.addChild(plotBitmap);
			
			// make selectionFilter appear in session state.
			registerLinkableChild(this, selectionFilter);
