You should call the method [font=courier new]getClosestItemAt[/font] available in HomeComponent3D class in a listener added to the displayed canvas. If the returned object is an instance of HomePieceOfFurniture, then you may call its [font=courier new]getCatalogId[/font] method to get its catalog ID and do whatever you want.
The [font=courier new]HomeComponent3D[/font] instance is returned by the getComponent3D method available on the object returned by viewHome function.