Use unicode-range to prevent unnecessary @font-face donwnloads

Source/core/platform/graphics/SimpleFontData.cpp

 /*
  * Copyright (C) 2005, 2008, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Alexey Proskuryakov
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
@@ skipping 12 matching lines @@
  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
 #include "core/platform/graphics/SimpleFontData.h"
 
+#include "core/css/CSSFontFaceSource.h"
 #include "core/platform/graphics/opentype/OpenTypeVerticalData.h"
 
 #include "wtf/MathExtras.h"
 #include "wtf/UnusedParam.h"
 
 using namespace std;
 
 namespace WebCore {
 
 const float smallCapsFontSizeMultiplier = 0.7f;
 const float emphasisMarkFontSizeMultiplier = 0.5f;
 
-SimpleFontData::SimpleFontData(const FontPlatformData& platformData, bool isCustomFont, bool isLoading, bool isTextOrientationFallback)
+SimpleFontData::SimpleFontData(const FontPlatformData& platformData, bool isCustomFont, bool isLoadingFallback, bool isTextOrientationFallback)
     : m_maxCharWidth(-1)
     , m_avgCharWidth(-1)
     , m_platformData(platformData)
     , m_treatAsFixedPitch(false)
     , m_isCustomFont(isCustomFont)
-    , m_isLoading(isLoading)
+    , m_isLoadingFallback(isLoadingFallback)
     , m_isTextOrientationFallback(isTextOrientationFallback)
     , m_isBrokenIdeographFallback(false)
 #if ENABLE(OPENTYPE_VERTICAL)
     , m_verticalData(0)
 #endif
     , m_hasVerticalGlyphs(false)
+    , m_isUsed(false)

[eseidel, 2013/09/10 15:07:26]

We should make this name more explicit so that we know that it's only used for
custom fonts.

[Kunihiko Sakamoto, 2013/09/11 13:28:09]

Now it's m_customFontData.isUsed.

+    , m_fontFaceSource(0)
 {
     platformInit();
     platformGlyphInit();
     platformCharWidthInit();
 #if ENABLE(OPENTYPE_VERTICAL)
     if (platformData.orientation() == Vertical && !isTextOrientationFallback) {
         m_verticalData = platformData.verticalData();
         m_hasVerticalGlyphs = m_verticalData.get() && m_verticalData->hasVerticalMetrics();
     }
 #endif
 }
 
 SimpleFontData::SimpleFontData(PassOwnPtr<AdditionalFontData> fontData, float fontSize, bool syntheticBold, bool syntheticItalic)
     : m_platformData(FontPlatformData(fontSize, syntheticBold, syntheticItalic))
     , m_fontData(fontData)
     , m_treatAsFixedPitch(false)
     , m_isCustomFont(true)
-    , m_isLoading(false)
+    , m_isLoadingFallback(false)
     , m_isTextOrientationFallback(false)
     , m_isBrokenIdeographFallback(false)
 #if ENABLE(OPENTYPE_VERTICAL)
     , m_verticalData(0)
 #endif
     , m_hasVerticalGlyphs(false)
+    , m_isUsed(false)
+    , m_fontFaceSource(0)
 {
     m_fontData->initializeFontData(this, fontSize);
 }
 
 // Estimates of avgCharWidth and maxCharWidth for platforms that don't support accessing these values from the font.
 void SimpleFontData::initCharWidths()
 {
     GlyphPage* glyphPageZero = GlyphPageTreeNode::getRootChild(this, 0)->page();
 
     // Treat the width of a '0' as the avgCharWidth.
@@ skipping 127 matching lines @@
 {
     if (!m_derivedFontData)
         m_derivedFontData = DerivedFontData::create(isCustomFont());
     if (!m_derivedFontData->brokenIdeograph) {
         m_derivedFontData->brokenIdeograph = create(m_platformData, isCustomFont(), false);
         m_derivedFontData->brokenIdeograph->m_isBrokenIdeographFallback = true;
     }
     return m_derivedFontData->brokenIdeograph;
 }
 
+void SimpleFontData::beginLoadIfNeeded() const
+{
+    if (!m_isUsed && m_isLoadingFallback && m_fontFaceSource) {
+        m_isUsed = true;
+        m_fontFaceSource->beginLoadingFontSoon();
+    }
+}
+
 #ifndef NDEBUG
 String SimpleFontData::description() const
 {
     if (isSVGFont())
         return "[SVG font]";
     if (isCustomFont())
         return "[custom font]";
 
     return platformData().description();
 }
@@ skipping 24 matching lines @@
 PassRefPtr<SimpleFontData> SimpleFontData::createScaledFontData(const FontDescription& fontDescription, float scaleFactor) const
 {
     // FIXME: Support scaled fonts that used AdditionalFontData.
     if (m_fontData)
         return 0;
 
     return platformCreateScaledFontData(fontDescription, scaleFactor);
 }
 
 } // namespace WebCore