function get_template_directory() {
  $template     = get_template();
  $theme_root   = get_theme_root( $template );
  $template_dir = "$theme_root/$template";

  
/**
 * Filters the active theme directory path.
 *
 * @since 1.5.0
 *
 * @param string $template_dir The path of the active theme directory.
 * @param string $template     Directory name of the active theme.
 * @param string $theme_root   Absolute path to the themes directory.
 */
  return apply_filters( 'template_directory', $template_dir, $template, $theme_root );
}