sub _atlayer
{
    #$_[0] = shift;
    local $_ = clone($_[1]);
    #$_->{$_} = $_[1]->{$_} foreach keys %{$_[1]};
    $_->[AS_BG]    = $_[0]->[AS_BG]    if !$_->[AS_BG];
    $_->[AS_FG]    = $_[0]->[AS_FG]    if !$_->[AS_FG];
    $_->[AS_U]    = $_[0]->[AS_U]        if  $_->[AS_U] < 0;
    $_->[AS_BOLD]    = $_[0]->[AS_BOLD]    if  $_->[AS_BOLD] < 0;
    $_->[AS_BLINK]    = $_[0]->[AS_BLINK]    if  $_->[AS_BLINK] < 0;
    return $_;
}