sub _atlayer
{
    local $_ = [ @$_[1] ];
    $_->[AS_BG]    ||= $_[0]->[AS_BG];
    $_->[AS_FG]    ||= $_[0]->[AS_FG];
    $_->[AS_U]     ||= $_[0]->[AS_U];
    $_->[AS_BOLD]  ||= $_[0]->[AS_BOLD];
    $_->[AS_BLINK] ||= $_[0]->[AS_BLINK];

    return $_;
}