(FontRenderer/FreeType) Use fontconfig to select fonts if available

Makefile.common

@@ -1079,6 +1079,10 @@ ifeq ($(HAVE_FREETYPE), 1)
    OBJ += gfx/drivers_font_renderer/freetype.o
    LIBS += $(FREETYPE_LIBS)
    DEF_FLAGS += $(FREETYPE_CFLAGS)
+   ifeq ($(HAVE_FREETYPE), 1)
+      LIBS += $(FONTCONFIG_LIBS)
+      DEF_FLAGS += $(FONTCONFIG_CFLAGS)
+   endif
 endif
 
 ifeq ($(HAVE_THREADS), 1)

gfx/drivers_font_renderer/freetype.c

@@ -27,6 +27,11 @@
 #include <retro_miscellaneous.h>
 #include <string/stdstring.h>
 
+#ifdef HAVE_FONTCONFIG
+#include <fontconfig/fontconfig.h>
+#include "../../msg_hash.h"
+#endif
+
 #ifdef WIIU
 #include <wiiu/os.h>
 #endif
@@ -240,6 +245,43 @@ static void *font_renderer_ft_init(const char *font_path, float font_size)
       err = FT_New_Memory_Face(handle->lib, font_data, font_size, 0, &handle->face);
    }
    else
+#elif HAVE_FONTCONFIG
+   // if fallback font is requested, instead of loading it, we find the full font in the system
+   if (!*font_path || strstr(font_path, "fallback"))
+   {
+      FcConfig* config = FcInitLoadConfigAndFonts();
+      FcResult result = FcResultNoMatch;
+      FcChar8* font_path = NULL;
+      int face_index = 0;
+      // select Sans fonts
+      FcPattern* pattern = FcNameParse((const FcChar8*)"Sans");
+      // since fontconfig uses LL-TT style, we need to normalize locale names
+      FcChar8* locale = FcLangNormalize((const FcChar8*)get_user_language_iso639_1(false));
+      // box the locale data in a FcValue container
+      FcValue locale_boxed = {.type = FcTypeString, {locale}};
+      // configure fontconfig substitute policies, this will increase the search scope
+      FcConfigSubstitute(config, pattern, FcMatchPattern);
+      // pull in system-wide defaults, so the font selection respects system (or user) configurations
+      FcDefaultSubstitute(pattern);
+      // override locale settins, since we are not using the system locale
+      FcPatternAdd(pattern, FC_LANG, locale_boxed, false);
+      // let's find the best matching font given our search criteria
+      FcPattern* found = FcFontMatch(config, pattern, &result);
+      // uh-oh, for some reason, we can't find any font
+      if (result != FcResultMatch)
+         goto error;
+      if (FcPatternGetString(found, FC_FILE, 0, &font_path) != FcResultMatch)
+         goto error;
+      if (FcPatternGetInteger(found, FC_INDEX, 0, &face_index) != FcResultMatch)
+         goto error;
+      // initialize font renderer
+      err = FT_New_Face(handle->lib, (const char*)font_path, face_index, &handle->face);
+      // free up fontconfig internal structures
+      FcPatternDestroy(pattern);
+      FcPatternDestroy(found);
+      FcStrFree(locale);
+      FcConfigDestroy(config);
+   } else
 #endif
    {
       if (!path_is_valid(font_path))
@@ -304,7 +346,9 @@ static const char *font_paths[] = {
 /* Highly OS/platform dependent. */
 static const char *font_renderer_ft_get_default_font(void)
 {
-#ifdef WIIU
+// Since fontconfig will return parameters more than a simple path
+// we will process these in the init function
+#if defined(WIIU) || defined(HAVE_FONTCONFIG)
    return "";
 #else
    size_t i;

qb/config.libs.sh

@@ -498,6 +498,7 @@ check_pkgconf DBUS dbus-1
 check_val '' UDEV "-ludev" '' libudev '' '' false
 check_val '' V4L2 -lv4l2 '' libv4l2 '' '' false
 check_val '' FREETYPE -lfreetype freetype2 freetype2 '' '' false
+check_val '' FONTCONFIG -lfontconfig fontconfig fontconfig '' '' false
 check_val '' X11 -lX11 '' x11 '' '' false
 
 if [ "$HAVE_X11" != 'no' ]; then