DouKaku?

%!PS

/pyramid { % (string) pyramid -
    dup length 1 sub dup -1 0 {
        dup { ( ) print } repeat
        1 2 index {
            2 index exch 1 getinterval print ( ) print
        } for
        ( ) =
    } for
} def

% ------- Test Code -------- 
(hoge) pyramid
(abracadabra) pyramid