namespace NT { /**
     * A scene graph, which is responsible for managing the heirarchy of objects in a scene (essentially,
     * it is the scene itself).
     */ export class SceneGraph { private _root : TEntity ; /** Creates a new SceneGraph */ public constructor ( ) { this . _root = new TEntity ( "__ROOT__" , this ) ; } /** Returns the root object. */ public get root ( ) : TEntity { return this . _root ; } /** Indicates if this scene is loaded. */ public get isLoaded ( ) : boolean { return this . _root . isLoaded ; } param entity public addObject ( entity ) { this . _root . addChild ( entity ) ; } param name public getEntityByName ( name ) { return this . _root . getEntityByName ( name ) ; } /** Loads this scene graph. */ public load ( ) { this . _root . load ( ) ; } param time public update ( time ) { this . _root . update ( time ) ; } /**
         * Renders this scene graph.
         */ public render ( renderView ) { this . _root . render ( renderView ) ; } } }