X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=scm%2Foutput-ps.scm;h=4cc714fdecf34ac05ae58d18c255ebed76b10f1b;hb=13d8b383afd5bceb11747f5a3ee79ee9d4eca0aa;hp=96238dcf4c70c178e796b1671e52acf48bd643a8;hpb=aac243bd9509b7fbba7d79bc12b3792b33f98e2a;p=lilypond.git

diff --git a/scm/output-ps.scm b/scm/output-ps.scm
index 96238dcf4c..4cc714fdec 100644
--- a/scm/output-ps.scm
+++ b/scm/output-ps.scm
@@ -1,49 +1,70 @@
-;;;; output-ps.scm -- implement Scheme output routines for PostScript
+;;;; output-ps.scm -- implement Scheme output interface for PostScript
 ;;;;
 ;;;;  source file of the GNU LilyPond music typesetter
 ;;;; 
 ;;;; (c)  1998--2004 Jan Nieuwenhuizen <janneke@gnu.org>
-;;;; Han-Wen Nienhuys <hanwen@cs.uu.nl>
+;;;;                 Han-Wen Nienhuys <hanwen@cs.uu.nl>
 
 ;;;; Note: currently misused as testbed for titles with markup, see
 ;;;;       input/test/title-markup.ly
 ;;;; 
 ;;;; TODO:
-;;;;   * UGR: SPACE character in CM* fonts
-;;;;   * text setting, kerning?
-;;;;   * linewidth
-;;;;   * font properties
-;;;;   * construction/customisation of title markup
-;;;;   * page layout
+;;;;   * %% Papersize in (header ...)
+;;;;   * text setting, kerning.
 ;;;;   * document output-interface
 
 (debug-enable 'backtrace)
 
-(define-module (scm output-ps))
-(define this-module (current-module))
-
-(use-modules
- (guile)
- (ice-9 regex)
- (srfi srfi-13)
- (lily))
-
-
-
-
-;;; Lily output interface, PostScript implementation --- cleanup and docme
-
-;;; Module entry
-(define-public (ps-output-expression expr port)
-  (display (expression->string expr) port))
+(define-module (scm output-ps)
+  #:re-export (quote)
+  #:export (define-fonts
+	     unknown
+	     output-paper-def
+	     output-scopes
+	     select-font
+	     blank
+	     dot
+	     beam
+	     bracket
+	     dashed-slur
+	     char
+	     dashed-line
+	     zigzag-line
+	     symmetric-x-triangle
+	     ez-ball
+	     comment
+	     end-output
+	     experimental-on
+	     repeat-slash
+	     header-end
+	     header
+	     placebox
+	     bezier-sandwich
+	     start-system
+	     stop-system
+	     stop-last-system
+	     horizontal-line
+	     filledbox
+	     round-filled-box
+	     text
+	     tuplet
+	     polygon
+	     draw-line
+	     define-origin
+	     no-origin
+	     start-page
+	     stop-page
+	     ))
+
+(use-modules (guile)
+	     (ice-9 regex)
+	     (srfi srfi-1)
+	     (srfi srfi-13)
+	     (lily))
 
 ;;; Global vars
-;; alist containing fontname -> fontcommand assoc (both strings)
-(define font-name-alist '())
-
-;; WIP -- stencils from markup? values of output-scopes
-(define header-stencil #f)
-
+(define page-count 0)
+(define page-number 0)
 
 ;;; helper functions, not part of output interface
 (define (escape-parentheses s)
@@ -53,6 +74,9 @@
   (cons (+ (car a) (car b))
 	(+ (cdr a) (cdr b))))
 
+(define (ps-encoding text)
+  (escape-parentheses text))
+
 ;; FIXME: lily-def
 (define (ps-string-def prefix key val)
   (string-append "/" prefix (symbol->string key) " ("
@@ -61,57 +85,60 @@
 
 (define (ps-number-def prefix key val)
   (let ((s (if (integer? val)
-	       (number->string val)
-	       (number->string (exact->inexact val)))))
+	       (ly:number->string val)
+	       (ly:number->string (exact->inexact val)))))
     (string-append "/" prefix (symbol->string key) " " s " def\n")))
 
 (define (tex-font? fontname)
   (equal? (substring fontname 0 2) "cm"))
 
 
+;;;
+;;; Lily output interface, PostScript implementation --- cleanup and docme
+;;;
 
 ;;; Output-interface functions
 (define (beam width slope thick blot)
   (string-append
-   (numbers->string (list slope width thick blot)) " draw_beam" ))
+   (ly:numbers->string (list slope width thick blot)) " draw_beam" ))
 
 ;; two beziers
 (define (bezier-sandwich l thick)
   (string-append 
-   (apply string-append (map number-pair->string l))
+   (string-join (map ly:number-pair->string l) " ")
+   " "
    (ly:number->string thick)
-   " draw_bezier_sandwich "))
+   " draw_bezier_sandwich"))
 
 (define (bracket arch_angle arch_width arch_height  height arch_thick thick)
   (string-append
-   (numbers->string
+   (ly:numbers->string
     (list arch_angle arch_width arch_height height arch_thick thick))
    " draw_bracket"))
 
-(define (char i)
+(define (char font i)
   (string-append 
-   "(\\" (inexact->string i 8) ") show " ))
+    (font-command font) " setfont " 
+   "(\\" (ly:inexact->string i 8) ") show" ))
 
 (define (comment s)
   (string-append "% " s "\n"))
 
 (define (dashed-line thick on off dx dy)
   (string-append 
-   (ly:number->string dx)
-   " "
-   (ly:number->string dy)
-   " "
+   (ly:number->string dx) " "
+   (ly:number->string dy) " "
    (ly:number->string thick)
    " [ "
-   (ly:number->string on)
-   " "
+   (ly:number->string on) " "
    (ly:number->string off)
    " ] 0 draw_dashed_line"))
 
 ;; what the heck is this interface ?
 (define (dashed-slur thick dash l)
   (string-append 
-   (apply string-append (map number-pair->string l)) 
+   (string-join (map ly:number-pair->string l) " ")
+   " "
    (ly:number->string thick) 
    " [ "
    (ly:number->string dash)
@@ -120,158 +147,150 @@
    (ly:number->string (* 10 thick))
    " ] 0 draw_dashed_slur"))
 
-(define (define-fonts internal-external-name-mag-pairs)
-
-  (define (fontname->designsize fontname)
-    (let ((i (string-index fontname char-numeric?)))
-      (string->number (substring fontname i))))
-			 
-  ;;  (define (font-load-command name-mag command)
-  (define (font-load-command lst)
-    (let* ((key-name-size (car lst))
-	   (value (cdr lst))
-	   (value-name-size (car value))
-	   (command (cdr value))
-	   (fontname (car value-name-size))
-	   (designsize (if (tex-font? fontname)
-			   (/ 12 (fontname->designsize fontname))
-			   ;; This is about 12/20 :-)
-			   (cdr key-name-size)))
-	   (fontsize (cdr value-name-size))
-	   (scaling (* 12 (/ fontsize designsize)))
-	   (scaling (/ fontsize (/ designsize 12))))
-
-      ;; frobnicate NAME to jibe with external definitions.
-      (define (possibly-mangle-fontname fontname)
-	(cond
-	 ((tex-font? fontname)
-	  ;; FIXME: we need proper Fontmap for CM fonts, like so:
-	  ;; /CMR10 (cmr10.pfb); 
-	  ;; (string-upcase fontname)
-	  (string-append fontname ".pfb"))
-	 ((or (equal? (substring fontname 0 4) "feta")
-	      (equal? (substring fontname 0 8) "parmesan"))
-	  (regexp-substitute/global
-	   #f "(feta|parmesan)([a-z-]*)([0-9]+)"
-	   fontname 'pre "GNU-LilyPond-" 1 2 "-" 3 'post))
-	 (else fontname)))
-      (if
-       #f
-       (begin
-	 (newline)
-	 (format (current-error-port) "key-name-size ~S\n" key-name-size)
-	 (format (current-error-port) "value ~S\n" value)
-	 (format (current-error-port) "value-name-size ~S\n" value-name-size)
-	 (format (current-error-port) "command ~S\n" command)
-	 (format (current-error-port) "designsize ~S\n" designsize)
-	 (format (current-error-port) "fontname ~S\n" fontname)
-	 (format (current-error-port) "fontsize ~S\n" fontsize)
-	 (format (current-error-port) "scaling ~S\n" scaling)))
-	 
+(define (font-command font . override-coding)
+  (let* ((name (ly:font-filename font))
+	 (magnify (ly:font-magnification font))
+	 (coding-alist (ly:font-encoding-alist font))
+	 (input-encoding (assoc-get 'input-name coding-alist))
+	 (font-encoding (assoc-get 'output-name coding-alist))
+	 (coding-command (if (null? override-coding)
+			     (if (equal? input-encoding font-encoding)
+				 #f font-encoding)
+			     (car override-coding))))
+
+    ;; FIXME:  now feta stuff has feta* input-encoding (again?)
+    ;;(format (current-error-port) "FONT: ~S, ~S\n" name font-encoding)
+    ;;(format (current-error-port) "INPUT: ~S\n" input-encoding)
+    (if (and coding-command (equal? (substring coding-command 0 4) "feta"))
+	(set! coding-command #f))
+
+    (string-append
+     "magfont" (string-encode-integer (hashq  name 1000000))
+     "m" (string-encode-integer (inexact->exact (round (* 1000 magnify))))
+     (if (not coding-command) "" (string-append "e" coding-command)))))
+
+(define (define-fonts paper font-list)
+  
+  (define (define-font command fontname scaling)
+    (string-append
+     "/" command " { /" fontname " findfont "
+     (ly:number->string scaling) " output-scale div scalefont } bind def\n"))
+
+  (define (reencode-font plain encoding command)
+    (let ((coding-vector (get-coding-command encoding)))
       (string-append
-       "/" command
-       " { /" (possibly-mangle-fontname fontname) " findfont "
-       (ly:number->string scaling)
-       "output-scale div scalefont setfont } bind def \n")))
-    
-  (define (ps-encoded-fontswitch name-mag-pair)
-    (let* ((key (car name-mag-pair))
-	   (value (cdr name-mag-pair))
-	   (fontname (car value))
-	   (scaling (cdr value)))
-      (cons key (cons value
-		      (string-append
-		       "lilyfont" fontname "-" (number->string scaling))))))
-
-  (set! font-name-alist
-	(map ps-encoded-fontswitch internal-external-name-mag-pairs))
-  (apply string-append (map font-load-command font-name-alist)))
+       plain " " coding-vector " /" command " reencode-font\n"
+       "/" command "{ /" command " findfont 1 scalefont } bind def\n")))
+  
+  (define (guess-ps-fontname basename)
+    "We do not have the FontName, try to guess is from basename."
+    (cond
+     ((tex-font? basename)
+      ;; FIXME: we need proper Fontmap for the bluesky CM*, EC* fonts.
+      ;; Only the fonts that we trace in mf/ are in our own FontMap.
+      (string-append basename ".pfb"))
+     (else (string-append basename ".pfa"))
+     ))
+
+  (define (font-load-command paper font)
+    (let* ((specced-font-name (ly:font-name font))
+	   (fontname (if specced-font-name
+			 specced-font-name
+			 (guess-ps-fontname (ly:font-filename font))))
+	   
+	   (coding-alist (ly:font-encoding-alist font))
+	   (input-encoding (assoc-get 'input-name coding-alist))
+	   (font-encoding (assoc-get 'output-name coding-alist))
+	   (command (font-command font))
+	   ;; FIXME -- see (font-command )
+	   (plain (font-command font #f))
+	   (designsize (ly:font-design-size font))
+	   (magnification (* (ly:font-magnification font)))
+	   (ops (ly:paper-lookup paper 'outputscale))
+	   (scaling (* ops magnification designsize)))
+
+      (string-append
+       (define-font plain fontname scaling)
+       (if (or (equal? input-encoding font-encoding)
+	       ;; guh
+	       (equal? font-encoding "fetaBraces")
+	       (equal? font-encoding "fetaNumber")
+	       (equal? font-encoding "fetaMusic")
+	       (equal? font-encoding "parmesanMusic"))
+	       ""
+	   (reencode-font plain input-encoding command)))))
+  
+  (define (font-load-encoding encoding)
+    (let ((filename (get-coding-filename encoding)))
+      (ly:kpathsea-gulp-file filename)))
+
+  (let* ((encoding-list (map (lambda (x)
+			       (assoc-get 'input-name
+					  (ly:font-encoding-alist x)))
+			     font-list))
+	 (encodings (uniq-list (sort-list (filter string? encoding-list)
+					  string<?))))
+
+    (string-append
+     (apply string-append (map font-load-encoding encodings))
+     (apply string-append
+	    (map (lambda (x) (font-load-command paper x)) font-list)))))
 
 (define (define-origin file line col) "")
 
 (define (dot x y radius)
   (string-append
    " "
-   (numbers->string
+   (ly:numbers->string
     (list x y radius)) " draw_dot"))
 
 (define (draw-line thick x1 y1 x2 y2)
   (string-append 
-  "	1 setlinecap
-	1 setlinejoin "
-  (ly:number->string thick)
-	" setlinewidth "
-   (ly:number->string x1)
-   " "
-   (ly:number->string y1)
-   " moveto "
-   (ly:number->string x2)
-   " "
-   (ly:number->string y2)
-   " lineto stroke"))
+   "1 setlinecap 1 setlinejoin "
+   (ly:number->string thick) " setlinewidth "
+   (ly:number->string x1) " "
+   (ly:number->string y1) " moveto "
+   (ly:number->string x2) " "
+   (ly:number->string y2) " lineto stroke"))
 
 (define (end-output)
   "\nend-lilypond-output\n")
 
-(define (expression->string expr)
-  (eval expr this-module))
-
 (define (ez-ball ch letter-col ball-col)
   (string-append
    " (" ch ") "
-   (numbers->string (list letter-col ball-col))
+   (ly:numbers->string (list letter-col ball-col))
    " /Helvetica-Bold " ;; ugh
    " draw_ez_ball"))
 
-(define (filledbox breapth width depth height) 
-  (string-append (numbers->string (list breapth width depth height))
+(define (filledbox breapth width depth height) ; FIXME : use draw_round_box
+  (string-append (ly:numbers->string (list breapth width depth height))
 		 " draw_box"))
 
-(define (fontify name-mag-pair exp)
-
-  (define (select-font name-mag-pair)
-    (let ((c (assoc name-mag-pair font-name-alist)))
-      
-      (if c
-	  (string-append " " (cddr c) " ")
-	  (begin
-	    (ly:warn
-	     (format "Programming error: No such font: ~S" name-mag-pair))
-	    
-	    (display "FAILED\n" (current-error-port))
-	    (if #f ;(pair? name-mag-pair))
-		(display (object-type (car name-mag-pair)) (current-error-port))
-		(write name-mag-pair (current-error-port)))
-	    (if #f ;  (pair? font-name-alist)
-		(display
-		 (object-type (caaar font-name-alist)) (current-error-port))
-		(write font-name-alist (current-error-port)))
-
-	    ;; (format #f "\n%FAILED: (select-font ~S)\n" name-mag-pair))
-	    ""))))
-  
-  (string-append (select-font name-mag-pair) exp))
-
-(define (header creator generate) 
+(define (header creator time-stamp paper page-count- classic?)
+  (set! page-count page-count-)
+  (set! page-number 0)
   (string-append
    "%!PS-Adobe-3.0\n"
-   "%%Creator: " creator generate "\n"))
+   "%%Creator: " creator " " time-stamp "\n"
+   "%%Pages: " (number->string page-count) "\n"
+   "%%PageOrder: Ascend\n"
+   "%%DocumentPaperSizes: " (ly:paper-lookup paper 'papersize) "\n"
+   ;;(string-append "GNU LilyPond (" (lilypond-version) "), ")
+   ;;	   (strftime "%c" (localtime (current-time))))
+   ;; FIXME: duplicated in every backend
+   (ps-string-def
+    "lilypond" 'tagline
+    (string-append "Engraved by LilyPond (version " (lilypond-version) ")"))))
 
 (define (header-end)
   (string-append
-   ;; URG: now we can't use scm output without Lily
    (ly:gulp-file "lilyponddefs.ps")
-   "{exch pop //systemdict /run get exec}\n\n"
-   (ly:gulp-file "music-drawing-routines.ps")
-   "{ exch pop //systemdict /run get exec }\n\n"
-   ;; ps-testing wreaks havoc when used with lilypond-book.
-   ;;  -- is this still true with new modules system?
-;;   (if (defined? 'ps-testing) "\n /testing true def" "")
-  ;   "\n /testing true def"
-   ))
+   (ly:gulp-file "music-drawing-routines.ps")))
 
+;; WTF is this in every backend?
 (define (horizontal-line x1 x2 th)
-  (draw-line th x1  0 x2 0))
+  (draw-line th x1 0 x2 0))
 
 (define (lily-def key val)
   (let ((prefix "lilypondpaper"))
@@ -281,21 +300,6 @@
 	(string-append "/" key " {" val "} bind def\n")
 	(string-append "/" key " (" val ") def\n"))))
 
-
-(define (make-title port)
-  (if header-stencil
-      (let ((x-ext (ly:stencil-get-extent header-stencil Y))
-	    (y-ext (ly:stencil-get-extent header-stencil X)))
-	;;(display (start-system (interval-length x-ext) (interval-length y-ext))
-	(display (start-system
-		  ;; output-scale trouble?
-		  (/ (interval-length x-ext) 2)
-		  (/ (interval-length y-ext) 2))
-		 port)
-	(output-stencil port (ly:stencil-get-expr header-stencil) '(0 . 0))
-	(display (stop-system) port)))
-  "")
-
 (define (no-origin) "")
 
 ;; FIXME: duplictates output-scopes, duplicated in other backends
@@ -304,11 +308,13 @@
   (let ((prefix "lilypondpaper"))
     
     (define (scope-entry->string key var)
-      (let ((val (variable-ref var)))
-	(cond
-	 ((string? val) (ps-string-def prefix key val))
-	 ((number? val) (ps-number-def prefix key val))
-	 (else ""))))
+      (if (variable-bound? var)
+	  (let ((val (variable-ref var)))
+	    (cond
+	     ((string? val) (ps-string-def prefix key val))
+	     ((number? val) (ps-number-def prefix key val))
+	     (else "")))
+	  ""))
       
     (apply
      string-append
@@ -317,148 +323,119 @@
 ;; FIXME: duplicated in other output backends
 ;; FIXME: silly interface name
 (define (output-scopes paper scopes fields basename)
+  (let ((prefix "lilypond"))
 
-  ;; FIXME: customise/generate these
-  (let ((props '(((font-family . roman)
-		  (word-space . 1)
-		  (baseline-skip . 2)
-		  (font-series . medium)
-		  (font-style . roman)
-		  (font-shape . upright)
-		  (font-size . 0))))
-	(prefix "lilypond")
-    	(stencils '())
-	(baseline-skip 2))
-
+    ;; FIXME: duplicates output-paper's scope-entry->string, mostly
     (define (scope-entry->string key var)
-      (let ((val (variable-ref var)))
-	
-	(if (memq key fields)
-	    (header-to-file basename key val))
-	
-	(cond
-	 ((eq? key 'font)
-	  BARF
-	  (format (current-error-port) "PROPS:~S\n" val)
-	  (set! props (cons val props))
-	  "")
-	 
-	 ;; define strings, for /make-lilypond-title to pick up
-	 ((string? val) (ps-string-def prefix key val))
-	 
-	 ;; generate stencil from markup
-	 ((markup? val) (set! stencils
-			      (append
-			       stencils
-			       (list
-				(interpret-markup paper props val))))
-	  "")
-	 ((number? val) (ps-number-def prefix key val))
-	 (else ""))))
+      (if (variable-bound? var)
+	  (let ((val (variable-ref var)))
+	    (if (and (memq key fields) (string? val))
+		(header-to-file basename key val))
+	    (cond
+	     ((string? val) (ps-string-def prefix key val))
+	     ((number? val) (ps-number-def prefix key val))
+	     (else "")))
+	  ""))
     
     (define (output-scope scope)
       (apply string-append (module-map scope-entry->string scope)))
 
-    (let ((s (string-append (apply string-append (map output-scope scopes)))))
-      (set! header-stencil (stack-lines DOWN 0 baseline-skip stencils))
-      
-      ;; trigger font load
-      (ly:stencil-get-expr header-stencil)
-      s)))
-
-;; hmm, looks like recursing call is always last statement, does guile
-;; think so too?
-(define (output-stencil port expr offset)
-  (if (pair? expr)
-      (let ((head (car expr)))
-	(cond
-	 ((ly:input-location? head)
-	  (display (apply define-origin (ly:input-location head)) port)
-	  (output-stencil port (cadr expr) offset))
-	 ((eq? head 'no-origin)
-	  (display (expression->string head) port)
-	  (output-stencil port (cadr expr) offset))
-	 ((eq? head 'translate-stencil)
-	  (output-stencil port (caddr expr) (offset-add offset (cadr expr))))
-	 ((eq? head 'combine-stencil)
-	  (output-stencil port (cadr expr) offset)
-	  (output-stencil port (caddr expr) offset))
-	 (else
-	  (display (placebox (car offset) (cdr offset)
-			     (expression->string expr)) port))))))
+    (string-append (apply string-append (map output-scope scopes)))))
 
 (define (placebox x y s) 
   (string-append 
-   (ly:number->string x) " " (ly:number->string y) " {" s "} place-box\n"))
+   (ly:number->string x) " " (ly:number->string y) " { " s " } place-box\n"))
 
 (define (polygon points blotdiameter)
   (string-append
-   " "
-   (numbers->string points)
-   (ly:number->string (/ (length points) 2))
+   (ly:numbers->string points) " "
+   (ly:number->string (/ (length points) 2)) " "
    (ly:number->string blotdiameter)
    " draw_polygon"))
 
 (define (repeat-slash wid slope thick)
   (string-append
-   (numbers->string (list wid slope thick))
+   (ly:numbers->string (list wid slope thick))
    " draw_repeat_slash"))
 
 (define (round-filled-box x y width height blotdiam)
    (string-append
-    " "
-    (numbers->string
+    (ly:numbers->string
      (list x y width height blotdiam)) " draw_round_box"))
 
-(define (symmetric-x-triangle thick w h)
-  (string-append
-   (numbers->string (list h w thick))
-   " draw_symmetric_x_triangle"))
-
-(define (start-system width height)
+(define (start-system origin dim)
   (string-append
-   "\n" (ly:number->string height)
-   " start-system\n"
+   "\n" (ly:number-pair->string origin) " start-system\n"
    "{\n"
    "set-ps-scale-to-lily-scale\n"))
 
-(define (stem breapth width depth height) 
+(define (stem breapth width depth height) ; FIXME: use draw_round_box.
   (string-append
-   (numbers->string (list breapth width depth height))
+   (ly:numbers->string (list breapth width depth height))
    " draw_box" ))
 
-(define (stop-last-system)
-  (stop-system))
-
-(define (stop-system)
-  "}\nstop-system\n")
+(define (stop-system last?)
+  "} stop-system\n")
 
-(define (text s)
-  (string-append "(" (escape-parentheses s) ") show "))
-
-;; top-of-file, wtf?
-(define (top-of-file)
-  (header (string-append "GNU LilyPond (" (lilypond-version) "), ")
-          (strftime "%c" (localtime (current-time))))
-  ;;; ugh
-  (ps-string-def
-   "lilypond" 'tagline
-   (string-append "Engraved by LilyPond (" (lilypond-version) ")")))
+(define (symmetric-x-triangle thick w h)
+  (string-append
+   (ly:numbers->string (list h w thick))
+   " draw_symmetric_x_triangle"))
 
+(define (text font s)
+  (let*
+      
+      (
+       ;; ugh, we should find a better way to
+       ;; extract the hsbw for /space from the font.
+       
+       (space-length (cdar (ly:text-dimension font "t"))) 
+       (commands '())
+       (add-command (lambda (x) (set! commands (cons x commands)))) )
+
+    (string-fold
+     (lambda (chr word)
+       "Translate space as into moveto, group the rest in words."
+       (if (and (< 0 (string-length word))
+		(equal? #\space  chr))
+	   (add-command 
+	    (string-append "(" (ps-encoding word) ") show\n")))
+
+       (if (equal? #\space  chr)
+	   (add-command  (string-append (number->string space-length) " 0.0 rmoveto ")) )
+       
+       (if (equal? #\space  chr)
+	   ""
+	   (string-append word (make-string 1 chr))))
+     ""
+     (string-append  s " "))
+
+    (string-append
+     (font-command font) " setfont "
+     (string-join (reverse commands)))
+    ))
+  
 (define (unknown) 
   "\n unknown\n")
 
 (define (zigzag-line centre? zzw zzh thick dx dy)
   (string-append
-    (if centre? "true" "false")
-    " "
-    (ly:number->string zzw)
-    " "
-    (ly:number->string zzh)
-    " "
-    (ly:number->string thick)
-    " 0 0 "
-    (ly:number->string dx)
-    " "
+    (if centre? "true" "false") " "
+    (ly:number->string zzw) " "
+    (ly:number->string zzh) " "
+    (ly:number->string thick) " "
+    "0 0 "
+    (ly:number->string dx) " "
     (ly:number->string dy)
-    " draw_zigzag_line "))
+    " draw_zigzag_line"))
+
+(define (start-page)
+  (set! page-number (+ page-number 1))
+  (string-append
+   "%%Page: " (number->string page-number) " " (number->string page-count) "\n"
+  "start-page\n"))
+
+(define (stop-page last?)
+  (if last?
+      "\nstop-last-page\n"
+      "\nstop-page\n"))