Allow changing of notation fonts

This commit changes the behaviour of make-pango-font-tree in the
following ways:

- Make all arguments optional key/value pairs
  keeping the current default values (emmentaler/Century Schoolbook)
- Allow changing of music fonts too.

Currently alternative music fonts have to be present in the font
directory besides Emmentaler fonts, and they have to be manually installed.
But now there are a number of alternative and compatible fonts available.

diff --git a/scm/font.scm b/scm/font.scm
index 867612ae11529c3426a795498a6dc5168481f427..e177a055edb31ca56bcc4030718b2b759da75c4a 100644 (file)
--- a/scm/font.scm
+++ b/scm/font.scm
@@ -147,7 +147,7 @@
 
 ;; Each size family is a vector of fonts, loaded with a delay.  The
 ;; vector should be sorted according to ascending design size.
-(define-public (add-music-fonts node name family design-size-alist factor)
+(define-public (add-music-fonts node family name brace design-size-alist factor)
   "Set up music fonts.
 
 Arguments:
@@ -155,13 +155,16 @@ Arguments:
 @item
 @var{node} is the font tree to modify.
 
+@item
+@var{family} is the family name of the music font.
+
 @item
 @var{name} is the basename for the music font.
 @file{@var{name}-<designsize>.otf} should be the music font,
-@file{@var{name}-brace.otf} should have piano braces.
 
 @item
-@var{family} is the family name of the music font.
+@var{brace} is the basename for the brace font.
+@file{@var{brace}-brace.otf} should have piano braces.
 
 @item
 @var{design-size-alist} is a list of @code{(rounded . designsize)}.
@@ -199,7 +202,7 @@ used.  This is used to select the proper design size for the text fonts.
                        )))
      (fetaBraces ,(ly:pt 20.0)
                  #(,(delay (ly:system-font-load
-                            (format #f "~a-brace" name)))))
+                            (format #f "~a-brace" brace)))))
      )))
 
 (define-public (add-pango-fonts node lily-family family factor)
@@ -229,9 +232,40 @@ used.  This is used to select the proper design size for the text fonts.
   (add-node 'italic 'normal)
   (add-node 'italic 'bold))
 
+; This function allows the user to change the specific fonts, leaving others
+; to the default values. This way, "make-pango-font-tree"'s syntax doesn't
+; have to change from the user's perspective.
+;
+; Usage:
+;   \paper {
+;     #(define fonts
+;       (set-global-fonts
+;        #:music "gonville"  ; (the main notation font)
+;        #:roman "FreeSerif" ; (the main/serif text font)
+;       ))
+;   }
+;
+; Leaving out "#:brace", "#:sans", and "#:typewriter" leave them at 
+; "emmentaler", "sans-serif", and "monospace", respectively. All fonts are
+; still accesible through the usual scheme symbols: 'feta, 'roman, 'sans, and
+; 'typewriter.
+(define*-public (set-global-fonts #:key 
+  (music "emmentaler")
+  (brace "emmentaler")
+  (roman "Century Schoolbook L")
+  (sans "sans-serif")
+  (typewriter "monospace")
+  (factor 1))
+  (let ((n (make-font-tree-node 'font-encoding 'fetaMusic)))
+    (add-music-fonts n 'feta music brace feta-design-size-mapping factor)
+    (add-pango-fonts n 'roman roman factor)
+    (add-pango-fonts n 'sans sans factor)
+    (add-pango-fonts n 'typewriter typewriter factor)
+    n))
+    
 (define-public (make-pango-font-tree roman-str sans-str typewrite-str factor)
   (let ((n (make-font-tree-node 'font-encoding 'fetaMusic)))
-    (add-music-fonts n "emmentaler" 'feta feta-design-size-mapping factor)
+    (add-music-fonts n 'feta "emmentaler" "emmentaler" feta-design-size-mapping factor)
     (add-pango-fonts n 'roman roman-str factor)
     (add-pango-fonts n 'sans sans-str factor)
     (add-pango-fonts n 'typewriter typewrite-str factor)
@@ -240,7 +274,9 @@ used.  This is used to select the proper design size for the text fonts.
 (define-public (make-century-schoolbook-tree factor)
   (make-pango-font-tree
    "Century Schoolbook L"
-   "sans-serif" "monospace" factor))
+   "sans-serif"
+   "monospace"
+   factor))
 
 (define-public all-text-font-encodings
   '(latin1))