[Qt] Support kerning in fast path font rendering

https://bugs.webkit.org/show_bug.cgi?id=106013

Reviewed by Jocelyn Turcotte.

To support kerning in the fast font path we need to implement SimpleFontData::applyTransforms.

This patch changes the types used by the fast path GlyphBuffer to match those used by Qt,
and implements SimpleFontData::applyTransforms using QRawFont::advancesForGlyphIndexes.

* platform/graphics/GlyphBuffer.h:
(GlyphBufferAdvance):
(WebCore::GlyphBufferAdvance::GlyphBufferAdvance):
(WebCore::GlyphBufferAdvance::setWidth):
(WebCore::GlyphBufferAdvance::width):
(WebCore::GlyphBufferAdvance::height):
(WebCore::GlyphBuffer::add):
* platform/graphics/SimpleFontData.h:
(WebCore::SimpleFontData::applyTransforms):
* platform/graphics/WidthIterator.h:
(WebCore::WidthIterator::supportsTypesettingFeatures):

Change-Id: I9c94b19a9ca94b15385dfe71d6f26d030de59544
git-svn-id: http://svn.webkit.org/repository/webkit/trunk@146209 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Reviewed-by: Jocelyn Turcotte <jocelyn.turcotte@digia.com>

2 files changed, 21 insertions, 3 deletions

diff --git a/Source/WebCore/platform/graphics/GlyphBuffer.h b/Source/WebCore/platform/graphics/GlyphBuffer.h
index 5feafb140..3aec08e65 100644
--- a/Source/WebCore/platform/graphics/GlyphBuffer.h
+++ b/Source/WebCore/platform/graphics/GlyphBuffer.h
@@ -56,6 +56,8 @@ class SimpleFontData;
 typedef cairo_glyph_t GlyphBufferGlyph;
 #elif OS(WINCE)
 typedef wchar_t GlyphBufferGlyph;
+#elif PLATFORM(QT)
+typedef quint32 GlyphBufferGlyph;
 #else
 typedef Glyph GlyphBufferGlyph;
 #endif
@@ -89,6 +91,18 @@ public:
 private:
     float advance;
 };
+#elif PLATFORM(QT)
+struct GlyphBufferAdvance : public QPointF {
+public:
+    GlyphBufferAdvance(const QPointF& advance)
+        : QPointF(advance)
+    {
+    }
+
+    void setWidth(qreal width) { QPointF::setX(width); }
+    qreal width() const { return QPointF::x(); }
+    qreal height() const { return QPointF::y(); }
+};
 #else
 typedef FloatSize GlyphBufferAdvance;
 #endif
@@ -156,6 +170,8 @@ public:
         m_advances.append(advance);
 #elif OS(WINCE)
         m_advances.append(width);
+#elif PLATFORM(QT)
+        m_advances.append(QPointF(width, 0));
 #else
         m_advances.append(FloatSize(width, 0));
 #endif
diff --git a/Source/WebCore/platform/graphics/WidthIterator.h b/Source/WebCore/platform/graphics/WidthIterator.h
index 1996a0978..8e4e06997 100644
--- a/Source/WebCore/platform/graphics/WidthIterator.h
+++ b/Source/WebCore/platform/graphics/WidthIterator.h
@@ -61,13 +61,15 @@ public:
 
     static bool supportsTypesettingFeatures(const Font& font)
     {
-#if !PLATFORM(MAC) || __MAC_OS_X_VERSION_MIN_REQUIRED <= 1080
-        return !font.typesettingFeatures();
-#else
+#if PLATFORM(MAC) && __MAC_OS_X_VERSION_MIN_REQUIRED > 1080
         if (!font.isPrinterFont())
             return !font.typesettingFeatures();
 
         return !(font.typesettingFeatures() & ~(Kerning | Ligatures));
+#elif PLATFORM(QT) && QT_VERSION >= 0x050100
+        return !(font.typesettingFeatures() & ~Kerning) && !font.isSmallCaps();
+#else
+        return !font.typesettingFeatures();
 #endif
     }