Bug 1300025. Use embedded bitmaps in CJK fonts with skia on Windows. r=lsalzman

gfx/2d/2D.h

@@ -1481,7 +1481,8 @@ public:
     CreateScaledFontForDWriteFont(IDWriteFont* aFont,
                                   IDWriteFontFamily* aFontFamily,
                                   IDWriteFontFace* aFontFace,
-                                  Float aSize);
+                                  Float aSize,
+                                  bool aUseEmbeddedBitmap);
 
 private:
   static ID2D1Device *mD2D1Device;

gfx/2d/DrawTargetSkia.cpp

@@ -41,6 +41,10 @@
 #include "CGTextDrawing.h"
 #endif
 
+#ifdef XP_WIN
+#include "ScaledFontDWrite.h"
+#endif
+
 namespace mozilla {
 namespace gfx {
 
@@ -1291,6 +1295,12 @@ DrawTargetSkia::FillGlyphs(ScaledFont *aFont,
     }
     break;
   }
+  case FontType::DWRITE:
+  {
+    ScaledFontDWrite* dwriteFont = static_cast<ScaledFontDWrite*>(aFont);
+    paint.mPaint.setEmbeddedBitmapText(dwriteFont->UseEmbeddedBitmaps());
+    break;
+  }
   default:
     break;
   }

gfx/2d/Factory.cpp

@@ -705,9 +705,10 @@ already_AddRefed<ScaledFont>
 Factory::CreateScaledFontForDWriteFont(IDWriteFont* aFont,
                                        IDWriteFontFamily* aFontFamily,
                                        IDWriteFontFace* aFontFace,
-                                       float aSize)
+                                       float aSize,
+                                       bool aUseEmbeddedBitmap)
 {
-  return MakeAndAddRef<ScaledFontDWrite>(aFont, aFontFamily, aFontFace, aSize);
+  return MakeAndAddRef<ScaledFontDWrite>(aFont, aFontFamily, aFontFace, aSize, aUseEmbeddedBitmap);
 }
 
 #endif // XP_WIN

gfx/2d/ScaledFontDWrite.h

@@ -23,14 +23,16 @@ public:
     , mFont(nullptr)
     , mFontFamily(nullptr)
     , mFontFace(aFont)
+    , mUseEmbeddedBitmap(false)
   {}
 
   ScaledFontDWrite(IDWriteFont* aFont, IDWriteFontFamily* aFontFamily,
-                   IDWriteFontFace *aFontFace, Float aSize)
+                   IDWriteFontFace *aFontFace, Float aSize, bool aUseEmbeddedBitmap)
     : ScaledFontBase(aSize)
     , mFont(aFont)
     , mFontFamily(aFontFamily)
     , mFontFace(aFontFace)
+    , mUseEmbeddedBitmap(aUseEmbeddedBitmap)
   {}
 
   virtual FontType GetType() const { return FontType::DWRITE; }
@@ -46,6 +48,8 @@ public:
 
   virtual AntialiasMode GetDefaultAAMode() override;
 
+  bool UseEmbeddedBitmaps() { return mUseEmbeddedBitmap; }
+
 #ifdef USE_SKIA
   virtual SkTypeface* GetSkTypeface();
   bool GetFontDataFromSystemFonts(IDWriteFactory* aFactory);
@@ -56,6 +60,7 @@ public:
   RefPtr<IDWriteFont> mFont;
   RefPtr<IDWriteFontFamily> mFontFamily;
   RefPtr<IDWriteFontFace> mFontFace;
+  bool mUseEmbeddedBitmap;
 
 protected:
 #ifdef USE_CAIRO_SCALED_FONT

gfx/thebes/gfxDWriteFonts.cpp

@@ -702,9 +702,14 @@ gfxDWriteFont::GetScaledFont(mozilla::gfx::DrawTarget *aTarget)
                                                         GetAdjustedSize(),
                                                         GetCairoScaledFont());
   } else if (aTarget->GetBackendType() == BackendType::SKIA) {
+    gfxDWriteFontEntry *fe =
+        static_cast<gfxDWriteFontEntry*>(mFontEntry.get());
+    bool useEmbeddedBitmap = (fe->IsCJKFont() && HasBitmapStrikeForSize(NS_lround(mAdjustedSize)));
+
     mAzureScaledFont =
             Factory::CreateScaledFontForDWriteFont(mFont, mFontFamily,
-                                                   mFontFace, GetAdjustedSize());
+                                                   mFontFace, GetAdjustedSize(),
+                                                   useEmbeddedBitmap);
   } else {
     mAzureScaledFont = Factory::CreateScaledFontForNativeFont(nativeFont,
                                                             GetAdjustedSize());