[pango/regular-face] fontconfig: Try harder to find a default face

[Matthias Clasen <matthiasc src gnome org>]

commit 3c995c9357c4168c737dce1e8663ce6fe8df88e8
Author: Matthias Clasen <mclasen redhat com>
Date:   Fri Nov 6 11:24:47 2020 -0500

    fontconfig: Try harder to find a default face
    
    Fonts are amazing, and not in a good way. My system has
    fonts with 0, 1, 2 "Regular" faces. It also has fonts
    where the "Regular" face is, in fact, bold.
    
    So, we need to work even harder to return a reasonable
    face when asked about the default. We already make
    a determination of faces that we consider 'regular'
    when we create the faces initially. Just keep that
    information for later reuse.

 pango/pangofc-fontmap.c | 31 +++++++++++++++++++++++--------
 1 file changed, 23 insertions(+), 8 deletions(-)
---
diff --git a/pango/pangofc-fontmap.c b/pango/pangofc-fontmap.c
index 3b7f1915..764336ae 100644
--- a/pango/pangofc-fontmap.c
+++ b/pango/pangofc-fontmap.c
@@ -182,6 +182,7 @@ struct _PangoFcFace
   FcPattern *pattern;
 
   guint fake : 1;
+  guint regular : 1;
 };
 
 struct _PangoFcFamily
@@ -2852,6 +2853,7 @@ ensure_faces (PangoFcFamily *fcfamily)
          fcfamily->faces[i++] = create_face (fcfamily, "Bold", NULL, TRUE);
          fcfamily->faces[i++] = create_face (fcfamily, "Italic", NULL, TRUE);
          fcfamily->faces[i++] = create_face (fcfamily, "Bold Italic", NULL, TRUE);
+          fcfamily->faces[0]->regular = 1;
        }
       else
        {
@@ -2865,12 +2867,17 @@ ensure_faces (PangoFcFamily *fcfamily)
          gboolean has_face [4] = { FALSE, FALSE, FALSE, FALSE };
          PangoFcFace **faces;
          gint num = 0;
+          int regular_weight;
+          int regular_idx;
 
          fontset = fcfamily->patterns;
 
          /* at most we have 3 additional artifical faces */
          faces = g_new (PangoFcFace *, fontset->nfont + 3);
 
+          regular_weight = 0;
+          regular_idx = -1;
+
          for (i = 0; i < fontset->nfont; i++)
            {
              const char *style, *font_style = NULL;
@@ -2895,12 +2902,23 @@ ensure_faces (PangoFcFamily *fcfamily)
              if (FcPatternGetString (fontset->fonts[i], FC_STYLE, 0, (FcChar8 **)(void*)&font_style) != 
FcResultMatch)
                font_style = NULL;
 
+              if (font_style && strcmp (font_style, "Regular") == 0)
+                {
+                  regular_weight = FC_WEIGHT_MEDIUM;
+                  regular_idx = num;
+                }
+
              if (weight <= FC_WEIGHT_MEDIUM)
                {
                  if (slant == FC_SLANT_ROMAN)
                    {
                      has_face[REGULAR] = TRUE;
                      style = "Regular";
+                      if (weight > regular_weight)
+                        {
+                          regular_weight = weight;
+                          regular_idx = num;
+                        }
                    }
                  else
                    {
@@ -2938,6 +2956,9 @@ ensure_faces (PangoFcFamily *fcfamily)
          if ((has_face[REGULAR] || has_face[ITALIC] || has_face[BOLD]) && !has_face[BOLD_ITALIC])
            faces[num++] = create_face (fcfamily, "Bold Italic", NULL, TRUE);
 
+          if (regular_idx != -1)
+            faces[regular_idx]->regular = 1;
+
          faces = g_renew (PangoFcFace *, faces, num);
 
           qsort (faces, num, sizeof (PangoFcFace *), compare_face);
@@ -2979,24 +3000,18 @@ pango_fc_family_get_face (PangoFontFamily *family,
 {
   PangoFcFamily *fcfamily = PANGO_FC_FAMILY (family);
   int i;
-  const char *style = name;
 
   ensure_faces (fcfamily);
 
-  if (style == NULL)
-    style = "Regular";
-
   for (i = 0; i < fcfamily->n_faces; i++)
     {
       PangoFontFace *face = PANGO_FONT_FACE (fcfamily->faces[i]);
 
-      if (strcmp (style, pango_font_face_get_face_name (face)) == 0)
+      if ((name != NULL && strcmp (name, pango_font_face_get_face_name (face)) == 0) ||
+          (name == NULL && PANGO_FC_FACE (face)->regular))
         return face;
     }
 
-  if (name == NULL && fcfamily->n_faces > 0)
-    return PANGO_FONT_FACE (fcfamily->faces[0]);
-
   return NULL;
 }