public function getAssets($group='head',$type=null) {
		$assets = array();
		if (!isset($this->assets[$group]))
			return $assets;
		$types = array_keys($this->assets[$group]);
		foreach($types as $asset_type) {
			if ($type && $type!=$asset_type)
				continue;
			krsort($this->assets[$group][$asset_type]);
			foreach($this->assets[$group][$asset_type] as $prio_set)
				foreach($prio_set as $asset) {
					if ($asset['origin']=='inline')
						$assets[$asset_type][$asset['data']] = $asset;
					else
						$assets[$asset_type][$asset['path']] = $asset;
				}
			$assets[$asset_type] = array_values($assets[$asset_type]);
		}
		return $assets;
	}