macOS: Defer population of localized font family aliases until needed

Getting the localized family name of a font involves quite a bit of work
internally in CoreText, e.g. creating and sorting font descriptors.

By deferring population of family aliases until a font match misses
we shave off ~1 second of startup time for applications that use non-
localized font families (most applications).

Change-Id: I021952c311c0d70d7769ccf764dbf997ebf30a4b
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@qt.io>

1 files changed, 4 insertions, 0 deletions

diff --git a/src/gui/text/qfontdatabase.cpp b/src/gui/text/qfontdatabase.cpp
index 43648d0f7f..58933e38fb 100644
--- a/src/gui/text/qfontdatabase.cpp
+++ b/src/gui/text/qfontdatabase.cpp
@@ -2678,6 +2678,10 @@ QFontEngine *QFontDatabase::findFont(const QFontDef &request, int script)
     QtFontDesc desc;
     QList<int> blackListed;
     int index = match(multi ? QChar::Script_Common : script, request, family_name, foundry_name, &desc, blackListed);
+    if (index < 0 && QGuiApplicationPrivate::platformIntegration()->fontDatabase()->populateFamilyAliases()) {
+        // We populated familiy aliases (e.g. localized families), so try again
+        index = match(multi ? QChar::Script_Common : script, request, family_name, foundry_name, &desc, blackListed);
+    }
     if (index >= 0) {
         engine = loadEngine(script, request, desc.family, desc.foundry, desc.style, desc.size);
         if (engine)