Merge "Add Harfbuzz support for fallback fonts (redux)"

3 files changed, 90 insertions, 5 deletions

diff --git a/Source/WebCore/platform/graphics/android/FontAndroid.cpp b/Source/WebCore/platform/graphics/android/FontAndroid.cpp
index b56e37c..31589e3 100644
--- a/Source/WebCore/platform/graphics/android/FontAndroid.cpp
+++ b/Source/WebCore/platform/graphics/android/FontAndroid.cpp
@@ -426,7 +426,21 @@ public:
     }
 
 private:
+    enum CustomScript {
+        Hindi,
+        Thai,
+        Naskh,
+        Hebrew,
+        HebrewBold,
+        NUM_SCRIPTS
+    };
+
+    static const char* paths[NUM_SCRIPTS];
+    static const FontPlatformData* s_fallbackPlatformData[NUM_SCRIPTS];
+
     void setupFontForScriptRun();
+    const FontPlatformData* setupComplexFont(CustomScript script,
+                const FontPlatformData& platformData);
     HB_FontRec* allocHarfbuzzFont();
     void deleteGlyphArrays();
     void createGlyphArrays(int);
@@ -468,6 +482,18 @@ private:
 };
 
 
+// Indexed using enum CustomScript
+const char* TextRunWalker::paths[] = {
+    "/system/fonts/Lohit_Hindi.ttf",
+    "/system/fonts/DroidSansThai.ttf",
+    "/system/fonts/DroidNaskh-Regular.ttf",
+    "/system/fonts/DroidSansHebrew-Regular.ttf",
+    "/system/fonts/DroidSansHebrew-Bold.ttf"
+};
+
+// Indexed using enum CustomScript
+const FontPlatformData* TextRunWalker::s_fallbackPlatformData[] = {};
+
 TextRunWalker::TextRunWalker(const TextRun& run, unsigned startingX, const Font* font)
     : m_font(font)
     , m_startingX(startingX)
@@ -620,15 +646,60 @@ void TextRunWalker::setWordAndLetterSpacing(int wordSpacingAdjustment,
     setLetterSpacingAdjustment(letterSpacingAdjustment);
 }
 
+const FontPlatformData* TextRunWalker::setupComplexFont(
+        CustomScript script,
+        const FontPlatformData& platformData)
+{
+    if (!s_fallbackPlatformData[script]) {
+        SkTypeface* typeface = SkTypeface::CreateFromFile(paths[script]);
+        s_fallbackPlatformData[script] = new FontPlatformData(platformData, typeface);
+        SkSafeUnref(typeface);
+    }
+
+    // If we couldn't allocate a new FontPlatformData, revert to the one passed
+    if (!s_fallbackPlatformData[script])
+        return &platformData;
+
+    return s_fallbackPlatformData[script];
+}
+
 void TextRunWalker::setupFontForScriptRun()
 {
-    const FontData* fontData = m_font->glyphDataForCharacter(
-        m_item.string[m_item.item.pos], false).fontData;
+    const FontData* fontData = m_font->glyphDataForCharacter(m_run[0], false).fontData;
     const FontPlatformData& platformData =
         fontData->fontDataForCharacter(' ')->platformData();
-    m_item.face = platformData.harfbuzzFace();
-    void* opaquePlatformData = const_cast<FontPlatformData*>(&platformData);
-    m_item.font->userData = opaquePlatformData;
+    const FontPlatformData* complexPlatformData = &platformData;
+
+    switch (m_item.item.script) {
+        case HB_Script_Devanagari:
+            complexPlatformData = setupComplexFont(Hindi, platformData);
+            break;
+        case HB_Script_Thai:
+            complexPlatformData = setupComplexFont(Thai, platformData);
+            break;
+        case HB_Script_Arabic:
+            complexPlatformData = setupComplexFont(Naskh, platformData);
+            break;
+        case HB_Script_Hebrew:
+            switch (platformData.typeface()->style()) {
+                case SkTypeface::kBold:
+                case SkTypeface::kBoldItalic:
+                    complexPlatformData = setupComplexFont(HebrewBold, platformData);
+                    break;
+                case SkTypeface::kNormal:
+                case SkTypeface::kItalic:
+                default:
+                    complexPlatformData = setupComplexFont(Hebrew, platformData);
+                    break;
+            }
+            break;
+        default:
+            // HB_Script_Common; includes Ethiopic
+            complexPlatformData = &platformData;
+            break;
+    }
+    m_item.face = complexPlatformData->harfbuzzFace();
+    m_item.font->userData = const_cast<FontPlatformData*>(complexPlatformData);
 }
 
 HB_FontRec* TextRunWalker::allocHarfbuzzFont()
diff --git a/Source/WebCore/platform/graphics/android/FontPlatformData.h b/Source/WebCore/platform/graphics/android/FontPlatformData.h
index 3313aca..56ce6e9 100644
--- a/Source/WebCore/platform/graphics/android/FontPlatformData.h
+++ b/Source/WebCore/platform/graphics/android/FontPlatformData.h
@@ -55,6 +55,7 @@ public:
     FontPlatformData(SkTypeface*, float textSize, bool fakeBold, bool fakeItalic);
     FontPlatformData(const FontPlatformData& src, float textSize);
     FontPlatformData(float size, bool syntheticBold, bool syntheticOblique);
+    FontPlatformData(const FontPlatformData& src, SkTypeface* typeface);
 
     ~FontPlatformData();
 
@@ -87,6 +88,7 @@ public:
 #endif
 
     HB_FaceRec_* harfbuzzFace() const;
+    SkTypeface* typeface() const { return mTypeface; }
 
 private:
     class RefCountedHarfbuzzFace : public RefCounted<RefCountedHarfbuzzFace> {
diff --git a/Source/WebCore/platform/graphics/android/FontPlatformDataAndroid.cpp b/Source/WebCore/platform/graphics/android/FontPlatformDataAndroid.cpp
index 337a94d..8e77b5b 100644
--- a/Source/WebCore/platform/graphics/android/FontPlatformDataAndroid.cpp
+++ b/Source/WebCore/platform/graphics/android/FontPlatformDataAndroid.cpp
@@ -127,6 +127,18 @@ FontPlatformData::FontPlatformData(float size, bool bold, bool oblique)
     trace(5);
 }
 
+FontPlatformData::FontPlatformData(const FontPlatformData& src, SkTypeface* tf)
+    : mTypeface(tf), mTextSize(src.mTextSize), mFakeBold(src.mFakeBold),
+      mFakeItalic(src.mFakeItalic)
+{
+    if (hashTableDeletedFontValue() != mTypeface) {
+        SkSafeRef(mTypeface);
+    }
+
+    inc_count();
+    trace(6);
+}
+
 FontPlatformData::~FontPlatformData()
 {
     dec_count();