Work-around for Pango 1.36.7 which introduced 'Semi-Light' font weight,

bug #1364937.

(bzr r13341.1.238)

1 files changed, 31 insertions, 1 deletions

diff --git a/src/libnrtype/FontFactory.cpp b/src/libnrtype/FontFactory.cpp
index dd2ecddeb..56fc18c7f 100644
--- a/src/libnrtype/FontFactory.cpp
+++ b/src/libnrtype/FontFactory.cpp
@@ -97,6 +97,7 @@ font_factory::font_factory(void) :
     fontSize(512),
     loadedPtr(new FaceMapType())
 {
+    // std::cout << pango_version_string() << std::endl;
 #ifdef USE_PANGO_WIN32
 #else
     pango_ft2_font_map_set_resolution(PANGO_FT2_FONT_MAP(fontServer),
@@ -572,7 +573,7 @@ GList* font_factory::GetUIStyles(PangoFontFamily * in)
         if (faceDescr) {
             Glib::ustring familyUIName = GetUIFamilyString(faceDescr);
             Glib::ustring styleUIName = GetUIStyleString(faceDescr);
-
+            // std::cout << familyUIName << "  " << styleUIName << "  " << displayName << std::endl;
             // Disable synthesized (faux) font faces except for CSS generic faces
             if (pango_font_face_is_synthesized(faces[currentFace]) ) {
                 if (familyUIName.compare( "sans-serif" ) != 0 &&
@@ -584,6 +585,35 @@ GList* font_factory::GetUIStyles(PangoFontFamily * in)
                 }
             }
 
+            // Pango breaks the 1 to 1 mapping between Pango weights and CSS weights by
+            // adding Semi-Light (as of 1.36.7), Book (as of 1.24), and Ultra-Heavy (as of
+            // 1.24). We need to map these weights to CSS weights. Book and Ultra-Heavy
+            // are rarely used. Semi-Light (350) is problematic as it is halfway between
+            // Light (300) and Normal (400) and if care is not taken it is converted to
+            // Normal, rather than Light.
+            //
+            // Note: The ultimate solution to handling various weight in the same
+            // font family is to support the @font rules from CSS.
+            //
+            // Additional notes, helpful for debugging:
+            //   Pango's FC backend:
+            //     Weights defined in fontconfig/fontconfig.h
+            //     String equivalents in src/fcfreetype.c
+            //     Weight set from os2->usWeightClass
+            //   Use Fontforge: Element->Font Info...->OS/2->Misc->Weight Class to check font weight
+            size_t f = styleUIName.find( "Book" );
+            if( f != Glib::ustring::npos ) {
+                styleUIName.replace( f, 4, "Normal" );
+            }
+            f = styleUIName.find( "Semi-Light" );
+            if( f != Glib::ustring::npos ) {
+                styleUIName.replace( f, 10, "Light" );
+            }
+            f = styleUIName.find( "Ultra-Heavy" );
+            if( f != Glib::ustring::npos ) {
+                styleUIName.replace( f, 11, "Heavy" );
+            }
+
             if (!familyUIName.empty() && !styleUIName.empty()) {
                 // Add the style information
                 ret = g_list_append(ret, new StyleNames(styleUIName, displayName));