sub mesh (\@\@;\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@\@) {
    my $max = -1;
    $max < $#$_  &&  ($max = $#$_)  for @_;

    map { my $ix = $_; map $_->[$ix], @_; } 0..$max; 
}