setFileMap( fileMap ) {

		this.fileMap = fileMap;

		return this;

	}
Sets a map which maps referenced library filenames to new filenames.
If a fileMap is not specified (the default), library parts will be accessed by trial and
error in subfolders 'parts', 'p' and 'models'.

@param {Object<string,string>} fileMap - The file map to set.
@return {LDrawLoader} A reference to this loader.