private function build(level:Class):void {
            var sprite:ArcSprite = new ArcSprite(0, 0, level);
            var levelp:BitmapData = sprite.pixels;
            for (i = 0; i < BLOCKS_H; i++) {
                for (j = 0; j < BLOCKS_W; j++) {
                    var pixel:uint = levelp.getPixel(j, i);
                    if (pixel == 0xaaaaaa) continue;
                    addBlock(j, i, pixel);
                }
            }
        }

        private function addBlock(X:int, Y:int, P:uint):void {
            var c:Class;
            var tile:Tile;

            switch(P) {
                case 0xff0000:
                    tile = new Block(X, Y, Color.RED);
                break;
                case 0x0084ff:
                    tile = new Block(X, Y, Color.BLUE);
                break;
            }

            if (tile == null) return;
            this.add(tile);
        }