Move coverage bitmap from FontCollection to FontFamily

This will significantly reduce memory usage and also speed the creation
of new font families. In particular, the coverage bitmaps for the fonts
in the fallback stack will be computed once in the Zygote, rather than
separately in each app process.

Bug: 17756900
Change-Id: I66f5706bddd4658d78fe5b709f7251ca9d2ff4f8

1 files changed, 7 insertions, 0 deletions

diff --git a/include/minikin/FontFamily.h b/include/minikin/FontFamily.h
index bcc2e3a..08c7a2c 100644
--- a/include/minikin/FontFamily.h
+++ b/include/minikin/FontFamily.h
@@ -23,6 +23,7 @@
 #include <utils/TypeHelpers.h>
 
 #include <minikin/MinikinRefCounted.h>
+#include <minikin/SparseBitSet.h>
 
 namespace android {
 
@@ -139,6 +140,9 @@ public:
     size_t getNumFonts() const;
     MinikinFont* getFont(size_t index) const;
     FontStyle getStyle(size_t index) const;
+
+    // Get Unicode coverage. Lifetime of returned bitset is same as receiver.
+    const SparseBitSet* getCoverage();
 private:
     void addFontLocked(MinikinFont* typeface, FontStyle style);
 
@@ -152,6 +156,9 @@ private:
     FontLanguage mLang;
     int mVariant;
     std::vector<Font> mFonts;
+
+    SparseBitSet mCoverage;
+    bool mCoverageValid;
 };
 
 }  // namespace android