Maybe the best solution is to generate a postscript file and then use ps2ascii to convert from postscript to ascii. From the man page:

       ps2ascii uses gs(1) to  extract ASCII text from PostScript(tm) or
        Adobe Portable Document Format (PDF) files. If no files are specified
        on the command line, gs reads  from  standard input; but PDF input 
        must come from an explicitly-named file, not standard input.  
        If no output file is specified, the ASCII text is written to 
        standard output.

       ps2ascii doesn't look at font encoding, and isn't very good at dealing 
        with kerning, so for PostScript (but not currently PDF), you might
        consider pstotext from     
        http://www.research.digital.com/SRC/virtualpaper/pstotext.html
        You need at least version 1.8g for compatibility with Ghostscript 6.0.
        It is available from http://rpmfind.net/linux/RPM/pstotext.html
        (pick the most recent version).