+
+(define (filter-out pred? lst)
+ (filter (lambda (x) (not (pred? x))) lst))
+
+(define-public (font-name-split font-name)
+ "Return (FONT-NAME . DESIGN-SIZE) from FONT-NAME string or #f."
+ (let ((match (regexp-exec (make-regexp "(.*)-([0-9]*)") font-name)))
+ (if (regexp-match? match)
+ (cons (match:substring match 1) (match:substring match 2))
+ (cons font-name-designsize #f))))
+
+;; Example of a pango-physical-font
+;; ("Emmentaler-11" "/home/janneke/vc/lilypond/out/share/lilypond/current/fonts/otf/emmentaler-11.otf" 0)
+(define-public (pango-pf-font-name pango-pf)
+ "Return the font-name of the pango physical font PANGO-PF."
+ (list-ref pango-pf 0))
+(define-public (pango-pf-file-name pango-pf)
+ "Return the file-name of the pango physical font PANGO-PF."
+ (list-ref pango-pf 1))
+(define-public (pango-pf-fontindex pango-pf)
+ "Return the fontindex of the pango physical font PANGO-PF."
+ (list-ref pango-pf 2))
+
+(define (pango-font-name pango-font)
+ (pango-pf-font-name (car (ly:pango-font-physical-fonts pango-font))))
+
+(define-public (define-fonts paper define-font define-pango-pf)
+ "Return a string of all fonts used in PAPER, invoking the functions
+DEFINE-FONT DEFINE-PANGO-PF for producing the actual font definition."
+
+ (let* ((font-list (ly:paper-fonts paper))
+ (pango-fonts (filter ly:pango-font? font-list))
+ (other-fonts (filter-out ly:pango-font? font-list))
+ (other-font-names (map ly:font-name other-fonts))
+ (pango-only-fonts
+ (filter-out (lambda (x)
+ (member (pango-font-name x) other-font-names))
+ pango-fonts)))
+
+ (define (font-load-command font)
+ (let* ((font-name (ly:font-name font))
+ (designsize (ly:font-design-size font))
+ (magnification (* (ly:font-magnification font)))
+ (ops (ly:output-def-lookup paper 'output-scale))
+ (scaling (* ops magnification designsize)))
+ (if (equal? font-name "unknown")
+ (display (list font font-name)))
+ (define-font font font-name scaling)))
+
+ (define (pango-font-load-command pango-font)
+ (let* ((pango-pf (car (ly:pango-font-physical-fonts pango-font)))
+ (font-name (pango-pf-font-name pango-pf))
+ (scaling (ly:output-def-lookup paper 'output-scale)))
+ (if (equal? font-name "unknown")
+ (display (list pango-font font-name)))
+ (define-pango-pf pango-pf font-name scaling)))
+
+ (string-append
+ (apply string-append (map font-load-command other-fonts))
+ (apply string-append (map pango-font-load-command pango-only-fonts)))))