Fill headers

Filling headers is tricky because fill-column is measured in
characters but the font-size for headers is much larger than for
regular text. This change tries to accomodate this by taking the face
for the heading, getting it's font – a string like
"-BE5N-Iosevka-normal-normal-normal-*-29-*-*-*-d-0-iso10646-1" – turns
it into a spec and gets the size from there: 29. We can't use
something like (face-attribute face :height) directly because it might
return a font size in 1/10 point (if an interger) or as a scaling
factor (if a float). Thus, in order to avoid tracking down the face
inheritance tree, we're looking at the font name (a string), in either
XLFD, Fontconfig, or GTK+ format.

diff --git a/elpher.el b/elpher.el
index b2bc1c5..b57f2b8 100644 (file)
--- a/elpher.el
+++ b/elpher.el
@@ -1368,17 +1368,20 @@ treatment that a separate function is warranted."
 The gemini map file line describing the header is given
 by HEADER-LINE."
   (when (string-match "^\\(#+\\)[ \t]*" header-line)
-    (let ((level (length (match-string 1 header-line)))
-          (header (substring header-line (match-end 0))))
+    (let* ((level (length (match-string 1 header-line)))
+           (header (substring header-line (match-end 0)))
+          (face (pcase level
+                   (1 'elpher-gemini-heading1)
+                   (2 'elpher-gemini-heading2)
+                   (3 'elpher-gemini-heading3)
+                   (_ 'default)))
+          (fill-column (/ (* fill-column
+                             (font-get (font-spec :name (face-font 'default)) :size))
+                          (font-get (font-spec :name (face-font face)) :size))))
       (unless (display-graphic-p)
         (insert (make-string level ?#) " "))
-      (insert (propertize header 'face
-                          (pcase level
-                            (1 'elpher-gemini-heading1)
-                            (2 'elpher-gemini-heading2)
-                            (3 'elpher-gemini-heading3)
-                            (_ 'default)))
-              "\n"))))
+      (insert (propertize header 'face face))
+      (newline))))
 
 (defun elpher-gemini-insert-text (text-line)
   "Insert a plain non-preformatted TEXT-LINE into a text/gemini document.