\version "2.14.2"

% This example assumes an environment with xelatex and pdftops available in PATH

% if set later, paperScale is not updated!
#(set-global-staff-size 16)

% how is the staff-scaling
#(define-public paperScale 1.0)
\paper {
  #(set! paperScale (/ (* 1 cm) staff-space))
}

% get a string from a markup
% TBD convert bold, italic, etc. to latex-commands
% (snippet taken from the list)
#(define (markup->string mup conc)
        (let ((result ""))
             (map (lambda (x)
                          (begin
                            ;; if this is a concat-markup, do not insert blanks between string
                            (if (eq? x concat-markup)(set! conc #t))
                            (if (list? x)
                                (set! result 
                                  ;; if we are concatenating or we start with an empty result, don't add a blank
                                  (if (or conc (string=? result ""))
                                      (string-append result (markup->string x conc))
                                      (string-append result " " (markup->string x conc)))))
                            (if (string? x)
                                (set! result 
                                  ;; if we are concatenating or we start with an empty result, don't add a blank
                                  (if (or conc (string=? result ""))
                                      (string-append result x)
                                      (string-append result " " x))))
                            result))
                  mup)
             result)
)
% xetex markup command (could also be done with pdflatex)
#(define-markup-command (xetex layout props size m)(number? markup-list?)
  (let (
         ; width of our box in cm
         (width (/ (chain-assoc-get 'line-width props 0) paperScale))
         ; height of our box in cm
         (height (/ size paperScale))
         ; the text to fill into template.tex
         (text (markup->string m #f))
         ; basename of working files
         (basename (strftime "xelatex-%Y%m%d%H%M%S" (localtime (current-time))))
         ; result of each command
         (result 0)
         ; stencil to return
         (text-stencil empty-stencil))
       ; write <basename>.tex
       (with-output-to-file (format "~A.tex" basename) (lambda ()
                 (display (format "\\documentclass{scrartcl}
\\usepackage[paperwidth=~Acm,paperheight=~Acm,margin=1mm]{geometry}
\\usepackage[ngerman]{babel}
\\usepackage{fontspec}
\\setmainfont{DejaVu Sans}
\\begin{document}
~A
\\end{document}
" width height text))))
       ; produce pdf
       (set! result (system (format "xelatex \"~A.tex\"" basename)))
       ; convert first page to EPS
       (set! result (system (format "pdftops -eps -f 1 -l 1 \"~A.pdf\"" basename)))
       
       ; include EPS
       (set! text-stencil (eps-file->stencil Y size (format "~A.eps" basename)))
       ; remove working files
       (system (format "rm -v \"~A\".*" basename))
       ; return eps-stencil
       text-stencil
))

%%%%%%%%%%%%%%%%%%%%%%% Test
\markup \column {
  \box \xetex #45 {
    Lorem ipsum dolor sit amet, consectetuer adipiscing elit. 
    Aenean commodo ligula eget dolor. Aenean massa. 
    Cum sociis natoque penatibus et magnis dis parturient montes, 
    nascetur ridiculus mus. Donec quam felis, ultricies nec, pellentesque eu, pretium quis, sem. 
    Nulla consequat massa quis enim. Donec pede justo, fringilla vel, aliquet nec, vulputate eget, arcu. 
    In enim justo, rhoncus ut, imperdiet a, venenatis vitae, justo. Nullam dictum felis eu pede mollis pretium. 
    Integer tincidunt. Cras dapibus. Vivamus elementum semper nisi. Aenean vulputate eleifend tellus. 
    Aenean leo ligula, porttitor eu, consequat vitae, eleifend ac, enim. 
    Aliquam lorem ante, dapibus in, viverra quis, feugiat a, tellus. 
    Phasellus viverra nulla ut metus varius laoreet. Quisque rutrum. 
    Aenean imperdiet. Etiam ultricies nisi vel augue. Curabitur ullamcorper 
    ultricies nisi. Nam eget dui. Etiam rhoncus. Maecenas tempus, tellus eget 
    condimentum rhoncus, sem quam semper libero, sit amet adipiscing sem neque sed ipsum. 
    Nam quam nunc, blandit vel, luctus pulvinar, hendrerit id, lorem. 
    Maecenas nec odio et ante tincidunt tempus. Donec vitae sapien ut libero venenatis faucibus. 
    Nullam quis ante. Etiam sit amet orci eget eros faucibus tincidunt. Duis leo. Sed fringilla mauris sit amet nibh. 
  }
  \box {
    \override #'(line-width . 50)
    \xetex #90 {
      Lorem ipsum dolor sit amet, consectetuer adipiscing elit. 
      Aenean commodo ligula eget dolor. Aenean massa. 
      Cum sociis natoque penatibus et magnis dis parturient montes, 
      nascetur ridiculus mus. Donec quam felis, ultricies nec, pellentesque eu, pretium quis, sem. 
      Nulla consequat massa quis enim. Donec pede justo, fringilla vel, aliquet nec, vulputate eget, arcu. 
      In enim justo, rhoncus ut, imperdiet a, venenatis vitae, justo. Nullam dictum felis eu pede mollis pretium. 
      Integer tincidunt. Cras dapibus. Vivamus elementum semper nisi. Aenean vulputate eleifend tellus. 
      Aenean leo ligula, porttitor eu, consequat vitae, eleifend ac, enim. 
      Aliquam lorem ante, dapibus in, viverra quis, feugiat a, tellus. 
      Phasellus viverra nulla ut metus varius laoreet. Quisque rutrum. 
      Aenean imperdiet. Etiam ultricies nisi vel augue. Curabitur ullamcorper 
      ultricies nisi. Nam eget dui. Etiam rhoncus. Maecenas tempus, tellus eget 
      condimentum rhoncus, sem quam semper libero, sit amet adipiscing sem neque sed ipsum. 
      Nam quam nunc, blandit vel, luctus pulvinar, hendrerit id, lorem. 
      Maecenas nec odio et ante tincidunt tempus. Donec vitae sapien ut libero venenatis faucibus. 
      Nullam quis ante. Etiam sit amet orci eget eros faucibus tincidunt. Duis leo. Sed fringilla mauris sit amet nibh. 
    }
  }
}