Consolidate Font::codePath kerning & ligatures exceptions

Currently, we tweak the computed code path in several places to force
kerning & ligatures handling via the complex path. These checks
are identical and can be handled in codePath() instead.

The refactoring preserves existing logic.

R=eae@chromium.org,jbroman@chromium.org,dominik.rottsches@intel.com

Review URL: https://codereview.chromium.org/642863005

git-svn-id: svn://svn.chromium.org/blink/trunk@183562 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/Source/core/rendering/svg/SVGTextMetricsBuilder.cpp

@@ -79,7 +79,7 @@ SVGTextMetricsCalculator::SVGTextMetricsCalculator(RenderSVGInlineText* text)
     , m_totalWidth(0)
 {
     const Font& scaledFont = text->scaledFont();
-    CodePath codePath = scaledFont.codePath(m_run);
+    CodePath codePath = scaledFont.codePath(TextRunPaintInfo(m_run));
     m_isComplexText = codePath == ComplexPath;
     m_run.setCharacterScanForCodePath(!m_isComplexText);
     m_run.setUseComplexCodePath(m_isComplexText);

third_party/WebKit/Source/platform/fonts/Font.cpp

@@ -50,8 +50,6 @@ using namespace Unicode;
 
 namespace blink {
 
-CodePath Font::s_codePath = AutoPath;
-
 Font::Font()
 {
 }
@@ -110,12 +108,7 @@ float Font::drawText(GraphicsContext* context, const TextRunPaintInfo& runInfo,
     if (shouldSkipDrawing() && customFontNotReadyAction == DoNotPaintIfFontNotReady)
         return 0;
 
-    CodePath codePathToUse = codePath(runInfo.run);
-    // FIXME: Use the fast code path once it handles partial runs with kerning and ligatures. See http://webkit.org/b/100050
-    if (codePathToUse != ComplexPath && fontDescription().typesettingFeatures() && (runInfo.from || runInfo.to != runInfo.run.length()))
-        codePathToUse = ComplexPath;
-
-    if (codePathToUse != ComplexPath)
+    if (codePath(runInfo) != ComplexPath)
         return drawSimpleText(context, runInfo, point);
 
     return drawComplexText(context, runInfo, point);
@@ -126,12 +119,7 @@ void Font::drawEmphasisMarks(GraphicsContext* context, const TextRunPaintInfo& r
     if (shouldSkipDrawing())
         return;
 
-    CodePath codePathToUse = codePath(runInfo.run);
-    // FIXME: Use the fast code path once it handles partial runs with kerning and ligatures. See http://webkit.org/b/100050
-    if (codePathToUse != ComplexPath && fontDescription().typesettingFeatures() && (runInfo.from || runInfo.to != runInfo.run.length()))
-        codePathToUse = ComplexPath;
-
-    if (codePathToUse != ComplexPath)
+    if (codePath(runInfo) != ComplexPath)
         drawEmphasisMarksForSimpleText(context, runInfo, mark, point);
     else
         drawEmphasisMarksForComplexText(context, runInfo, mark, point);
@@ -150,7 +138,7 @@ static inline void updateGlyphOverflowFromBounds(const IntRectExtent& glyphBound
 
 float Font::width(const TextRun& run, HashSet<const SimpleFontData*>* fallbackFonts, GlyphOverflow* glyphOverflow) const
 {
-    CodePath codePathToUse = codePath(run);
+    CodePath codePathToUse = codePath(TextRunPaintInfo(run));
     if (codePathToUse != ComplexPath) {
         // The simple path can optimize the case where glyph overflow is not observable.
         if (codePathToUse != SimpleWithGlyphOverflowPath && (glyphOverflow && !glyphOverflow->computeBounds))
@@ -211,12 +199,7 @@ PassTextBlobPtr Font::buildTextBlob(const TextRunPaintInfo& runInfo, const Float
     if (shouldSkipDrawing() && customFontNotReadyAction == DoNotPaintIfFontNotReady)
         return nullptr;
 
-    CodePath codePathToUse = codePath(runInfo.run);
-    // FIXME: Use the fast code path once it handles partial runs with kerning and ligatures. See http://webkit.org/b/100050
-    if (codePathToUse != ComplexPath && fontDescription().typesettingFeatures() && (runInfo.from || runInfo.to != runInfo.run.length()))
-        codePathToUse = ComplexPath;
-
-    if (codePathToUse != ComplexPath)
+    if (codePath(runInfo) != ComplexPath)
         return buildTextBlobForSimpleText(runInfo, textOrigin, couldUseLCDRenderedText);
 
     return nullptr;
@@ -297,12 +280,11 @@ FloatRect Font::selectionRectForText(const TextRun& run, const FloatPoint& point
 {
     to = (to == -1 ? run.length() : to);
 
-    CodePath codePathToUse = codePath(run);
-    // FIXME: Use the fast code path once it handles partial runs with kerning and ligatures. See http://webkit.org/b/100050
-    if (codePathToUse != ComplexPath && fontDescription().typesettingFeatures() && (from || to != run.length()))
-        codePathToUse = ComplexPath;
+    TextRunPaintInfo runInfo(run);
+    runInfo.from = from;
+    runInfo.to = to;
 
-    if (codePathToUse != ComplexPath)
+    if (codePath(runInfo) != ComplexPath)
         return selectionRectForSimpleText(run, point, h, from, to, accountForGlyphBounds);
 
     return selectionRectForComplexText(run, point, h, from, to);
@@ -310,27 +292,18 @@ FloatRect Font::selectionRectForText(const TextRun& run, const FloatPoint& point
 
 int Font::offsetForPosition(const TextRun& run, float x, bool includePartialGlyphs) const
 {
-    // FIXME: Use the fast code path once it handles partial runs with kerning and ligatures. See http://webkit.org/b/100050
-    if (codePath(run) != ComplexPath && !fontDescription().typesettingFeatures())
+    if (codePath(TextRunPaintInfo(run)) != ComplexPath && !fontDescription().typesettingFeatures())
         return offsetForPositionForSimpleText(run, x, includePartialGlyphs);
 
     return offsetForPositionForComplexText(run, x, includePartialGlyphs);
 }
 
-void Font::setCodePath(CodePath p)
-{
-    s_codePath = p;
-}
-
-CodePath Font::codePath()
+CodePath Font::codePath(const TextRunPaintInfo& runInfo) const
 {
-    return s_codePath;
-}
+    const TextRun& run = runInfo.run;
 
-CodePath Font::codePath(const TextRun& run) const
-{
-    if (s_codePath != AutoPath)
-        return s_codePath;
+    if (fontDescription().typesettingFeatures() && (runInfo.from || runInfo.to != run.length()))
+        return ComplexPath;
 
 #if ENABLE(SVG_FONTS)
     if (run.renderingContext())

third_party/WebKit/Source/platform/fonts/Font.h

@@ -131,7 +131,7 @@ public:
     std::pair<GlyphData, GlyphPage*> glyphDataAndPageForCharacter(UChar32&, bool mirror, bool normalizeSpace = false, FontDataVariant = AutoVariant) const;
     bool primaryFontHasGlyphForCharacter(UChar32) const;
 
-    CodePath codePath(const TextRun&) const;
+    CodePath codePath(const TextRunPaintInfo&) const;
 
     PassTextBlobPtr buildTextBlob(const TextRunPaintInfo&, const FloatPoint& textOrigin, bool couldUseLCDRenderedText, CustomFontNotReadyAction = DoNotPaintIfFontNotReady) const;
     void drawTextBlob(GraphicsContext*, const SkTextBlob*, const SkPoint& origin) const;
@@ -167,11 +167,6 @@ private:
     friend class SVGTextRunRenderingContext;
 
 public:
-    // Useful for debugging the different font rendering code paths.
-    static void setCodePath(CodePath);
-    static CodePath codePath();
-    static CodePath s_codePath;
-
     FontSelector* fontSelector() const;
 
     FontFallbackList* fontList() const { return m_fontFallbackList.get(); }

third_party/WebKit/Source/platform/text/TextPath.h

@@ -33,7 +33,7 @@
 
 namespace blink {
 
-enum CodePath { AutoPath, SimplePath, ComplexPath, SimpleWithGlyphOverflowPath };
+enum CodePath { SimplePath, ComplexPath, SimpleWithGlyphOverflowPath };
 
 }